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<!DOCTYPE book PUBLIC "-//FreeBSD//DTD DocBook V4.1-Based Extension//EN" [
<!ENTITY % books.ent PUBLIC "-//FreeBSD//ENTITIES DocBook FreeBSD Books Entity Set//EN">
%books.ent;
<!ENTITY bibliography SYSTEM "../../../share/sgml/bibliography.sgml">
]>
<book>
<bookinfo>
<title>Frequently Asked Questions for FreeBSD 4.X, 5.X, and 6.X</title>
<corpauthor>The FreeBSD Documentation Project</corpauthor>
<pubdate>$FreeBSD$</pubdate>
<copyright>
<year>1995</year>
<year>1996</year>
<year>1997</year>
<year>1998</year>
<year>1999</year>
<year>2000</year>
<year>2001</year>
<year>2002</year>
<year>2003</year>
<year>2004</year>
<year>2005</year>
<holder>The FreeBSD Documentation Project</holder>
</copyright>
&bookinfo.legalnotice;
<legalnotice id="trademarks" role="trademarks">
&tm-attrib.freebsd;
&tm-attrib.3com;
&tm-attrib.adobe;
&tm-attrib.creative;
&tm-attrib.cvsup;
&tm-attrib.ibm;
&tm-attrib.ieee;
&tm-attrib.intel;
&tm-attrib.iomega;
&tm-attrib.linux;
&tm-attrib.microsoft;
&tm-attrib.mips;
&tm-attrib.netscape;
&tm-attrib.opengroup;
&tm-attrib.oracle;
&tm-attrib.sgi;
&tm-attrib.sparc;
&tm-attrib.sun;
&tm-attrib.usrobotics;
&tm-attrib.xfree86;
&tm-attrib.general;
</legalnotice>
<abstract>
<para>This is the FAQ for FreeBSD versions 4.X, 5.X, and 6.X.
All entries are assumed to be relevant to FreeBSD 4.0 and
later, unless otherwise noted. If you are interested in
helping with this project, send email to the &a.doc;. The
latest version of this document is always available from the
<ulink
url="http://www.FreeBSD.org/doc/en_US.ISO8859-1/books/faq/index.html">FreeBSD
World Wide Web server</ulink>. It may also be downloaded as
one large <ulink url="book.html">HTML</ulink> file with HTTP
or as plain text, &postscript;, PDF, etc. from the <ulink
url="ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/">FreeBSD FTP
server</ulink>. You may also want to <ulink
url="&url.base;/search/index.html">Search the
FAQ</ulink>.</para>
</abstract>
</bookinfo>
<chapter id="introduction">
<title>Introduction</title>
<para>Welcome to the FreeBSD 4.X-6.X FAQ!</para>
<para>As is usual with Usenet FAQs, this document aims to cover the
most frequently asked questions concerning the FreeBSD operating
system (and of course answer them!). Although originally intended
to reduce bandwidth and avoid the same old questions being asked
over and over again, FAQs have become recognized as valuable
information resources.</para>
<para>Every effort has been made to make this FAQ as informative as
possible; if you have any suggestions as to how it may be improved,
please feel free to mail them to the &a.doc;.</para>
<qandaset>
<qandaentry>
<question id="what-is-FreeBSD">
<para>What is FreeBSD?</para>
</question>
<answer>
<para>Briefly, FreeBSD is a &unix;&nbsp;like operating system for
the Alpha/AXP, AMD64 and &intel; EM64T, &i386; IA-64,
PC-98, and &ultrasparc; platforms
based on U.C. Berkeley's <quote>4.4BSD-Lite</quote>
release, with some <quote>4.4BSD-Lite2</quote>
enhancements. It is also based indirectly on William
Jolitz's port of U.C. Berkeley's <quote>Net/2</quote> to
the &i386;, known as <quote>386BSD</quote>, though very
little of the 386BSD code remains. A fuller description of
what FreeBSD is and how it can work for you may be found on
the <ulink url="&url.base;/index.html">FreeBSD home
page</ulink>.</para>
<para>FreeBSD is used by companies, Internet Service Providers,
researchers, computer professionals, students and home users
all over the world in their work, education and recreation.</para>
<para>For more detailed information on FreeBSD, please see the
<ulink url="&url.books.handbook;/index.html">FreeBSD
Handbook</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="FreeBSD-goals">
<para>What is the goal of the FreeBSD Project?</para>
</question>
<answer>
<para>The goal of the FreeBSD Project is to provide software
that may be used for any purpose and without strings attached.
Many of us have a significant investment in the code (and
project) and would certainly not mind a little financial
compensation now and then, but we definitely do not
insist on it. We believe that our first and foremost
<quote>mission</quote> is to provide code to any and all
comers, and for whatever purpose, so that the code gets the
widest possible use and provides the widest possible benefit.
This is, we believe, one of the most fundamental goals of Free
Software and one that we enthusiastically support.</para>
<para>That code in our source tree which falls under the
<ulink url="http://www.FreeBSD.org/copyright/COPYING">GNU
General Public License (GPL)</ulink> or <ulink
url="http://www.FreeBSD.org/copyright/COPYING.LIB">GNU
Library General Public License (LGPL)</ulink> comes with
slightly more strings attached, though at least on the
side of enforced access rather than the usual opposite.
Due to the additional complexities that can evolve in the
commercial use of GPL software, we do, however, endeavor
to replace such software with submissions under the more
relaxed <ulink
url="http://www.FreeBSD.org/copyright/freebsd-license.html">
FreeBSD license</ulink> whenever possible.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="bsd-license-restrictions">
<para>Does the FreeBSD license have any restrictions?</para>
</question>
<answer>
<para>Yes. Those restrictions do not control how you use
the code, merely how you treat the FreeBSD Project itself.
If you have serious license concerns, read the actual
<ulink
url="http://www.FreeBSD.org/copyright/freebsd-license.html">
license</ulink>. For the simply curious, the license can
be summarized like this.</para>
<itemizedlist>
<listitem>
<para>Do not claim that you wrote this.</para>
</listitem>
<listitem>
<para>Do not sue us if it breaks.</para>
</listitem>
</itemizedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="replace-current-OS">
<para>Can FreeBSD replace my current operating system?</para>
</question>
<answer>
<para>For most people, yes. But this question is not quite
that cut-and-dried.</para>
<para>Most people do not actually use an operating system.
They use applications. The applications are what really
use the operating system. FreeBSD is designed to provide
a robust and full-featured environment for applications.
It supports a wide variety of web browsers, office suites,
email readers, graphics programs, programming
environments, network servers, and just about everything
else you might want. Most of these applications can be
managed through the <ulink
url="http://www.FreeBSD.org/ports/">Ports
Collection</ulink>.</para>
<para>If you need to use an application that is only
available on one operating system, you simply cannot
replace that operating system. Chances are there is a very
similar application on FreeBSD, however. If you want a
solid office or Internet server, a reliable workstation,
or just the ability to do your job without interruptions,
FreeBSD will almost certainly do everything you need.
Many computer users across the world, including both
novices and experienced &unix; administrators, use FreeBSD
as their only desktop operating system.</para>
<para>If you are migrating to FreeBSD from some other &unix;
environment, you already know most of what you need to.
If your background is in graphic-driven operating systems
such as &windows; and older versions of &macos;, expect to
invest additional time learning the &unix; way of doing
things. This FAQ and the <ulink
url="&url.books.handbook;/index.html">FreeBSD Handbook</ulink> are
excellent places to start.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="why-called-FreeBSD">
<para>Why is it called FreeBSD?</para>
</question>
<answer>
<itemizedlist>
<listitem>
<para>It may be used free of charge, even by commercial
users.</para>
</listitem>
<listitem>
<para>Full source for the operating system is freely
available, and the minimum possible restrictions have
been placed upon its use, distribution and incorporation
into other work (commercial or non-commercial).</para>
</listitem>
<listitem>
<para>Anyone who has an improvement or bug fix is free
to submit their code and have it added to the source tree
(subject to one or two obvious provisions).</para>
</listitem>
</itemizedlist>
<para>It is worth pointing out that the word
<quote>free</quote> is being used in two ways here, one meaning
<quote>at no cost</quote>, the other meaning <quote>you can do
whatever you like</quote>. Apart from one or two things you
<emphasis>cannot</emphasis> do with the FreeBSD code, for
example pretending you wrote it, you can really do whatever you
like with it.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="differences-to-other-bsds">
<para>What are the differences between FreeBSD and NetBSD, OpenBSD,
and other open source BSD operating systems?</para>
</question>
<answer>
<para>James Howard wrote a good explanation of the history
and differences between the various projects for <ulink
url="http://www.daemonnews.org/">DaemonNews</ulink>,
called <ulink
url="http://www.daemonnews.org/200104/bsd_family.html">The
BSD Family Tree</ulink> which goes a fair way to answering
this question.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="latest-version">
<para>What is the latest version of FreeBSD?</para>
</question>
<!--
This answer is a hack to deal with the fact that for now there are
multiple "latest" versions of FreeBSD.
-->
<answer>
<para>At this point in FreeBSD's development, there are three
parallel development branches; releases are being made from
two of the three branches. The 4.X series of releases
is being made from the <emphasis>4-STABLE</emphasis> branch
and the 5.X series of releases is being made from
<emphasis>5-STABLE</emphasis>. It will be some time in
mid-to-late 2005 before the first release will be made from the
<emphasis>6-CURRENT</emphasis> branch; that release (6.0)
will be aimed at early adopters.</para>
<para>Up until the release of 5.3, the 4.X series was the
one known as <emphasis>-STABLE</emphasis>. However,
as of 5.3, 5.X has been designated the new
<emphasis>-STABLE</emphasis> and 4.X will no longer see
much new development. Instead, it will be designated
for an &quot;extended support&quot; status and receive
only fixes for major problems (such as security-related
fixes.)</para>
<!-- note: the entity definitions are out of date -->
<para>Version <ulink
url="ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/i386/&rel.current;-RELEASE/">&rel.current;</ulink>
is the latest release from the
<emphasis>5-STABLE</emphasis> branch; it was released in
&rel.current.date;. Version <ulink
url="ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/i386/&rel2.current;-RELEASE/">&rel2.current;</ulink>
is the latest release from the
<emphasis>4-STABLE</emphasis> branch; it was released in
&rel2.current.date;.</para>
<para>Briefly, <emphasis>-STABLE</emphasis> is aimed at the
ISP, corporate user, or any user who wants stability and a
minimal number of changes compared to the new (and
possibly unstable) features of the latest
<emphasis>-CURRENT</emphasis> snapshot. Releases can come
from either branch, but <emphasis>-CURRENT</emphasis>
should only be used if you are prepared for its increased
volatility (relative to <emphasis>-STABLE</emphasis>, that
is).</para>
<para>Releases are made <link linkend="release-freq">every
few months</link>. While many people stay more up-to-date with
the FreeBSD sources (see the questions on <link
linkend="current">FreeBSD-CURRENT</link> and <link
linkend="stable">FreeBSD-STABLE</link>) than that, doing so
is more of a commitment, as the sources are a moving
target.</para>
<para>More information on FreeBSD releases can be found on
the <ulink
url="http://www.FreeBSD.org/releng/index.html">Release
Engineering page</ulink> on the FreeBSD Web site.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="current">
<para>What is FreeBSD-CURRENT?</para>
</question>
<answer>
<para><ulink
url="&url.books.handbook;/cutting-edge.html#CURRENT">FreeBSD-CURRENT</ulink>
is the development version of the operating system, which
will in due course become the new &os.stable; branch.
As such, it is
really only of interest to developers working on the
system and die-hard hobbyists. See the <ulink
url="&url.books.handbook;/cutting-edge.html#CURRENT">relevant
section</ulink> in the <ulink
url="&url.books.handbook;/index.html">handbook</ulink> for details
on running -CURRENT.</para>
<para>If you are not familiar with the operating system or are
not capable of identifying the difference between a real
problem and a temporary problem, you should not use
FreeBSD-CURRENT. This branch sometimes evolves quite quickly
and can be un-buildable for a number of days at a time.
People that use FreeBSD-CURRENT are expected to be able to
analyze any problems and only report them if they are deemed
to be mistakes rather than <quote>glitches</quote>. Questions
such as <quote>make world produces some error about
groups</quote> on the -CURRENT mailing list may be
treated with contempt.</para>
<para>Every day, <ulink
url="&url.base;/releases/snapshots.html">snapshot
</ulink> releases are made based on the current state of the
-CURRENT and -STABLE branches. Distributions of the
occasional snapshot are made available. The goals
behind each snapshot release are:</para>
<itemizedlist>
<listitem>
<para>To test the latest version of the installation
software.</para>
</listitem>
<listitem>
<para>To give people who would like to run -CURRENT or
-STABLE but who do not have the time or bandwidth to
follow it on a day-to-day basis an easy way of
bootstrapping it onto their systems.</para>
</listitem>
<listitem>
<para>To preserve a fixed reference point for the code in
question, just in case we break something really badly
later. (Although CVS normally prevents anything horrible
like this happening :)</para>
</listitem>
<listitem>
<para>To ensure that all new features and fixes in need
of testing have the greatest possible number of
potential testers.</para>
</listitem>
</itemizedlist>
<para>No claims are made that any -CURRENT snapshot can be
considered <quote>production quality</quote> for any purpose.
If you want to run a stable and fully tested system, you will
have to stick to full releases, or use the -STABLE
snapshots.</para>
<para>Snapshot releases are directly available from <ulink
url="ftp://current.FreeBSD.org/pub/FreeBSD/snapshots/">
ftp://current.FreeBSD.org/pub/FreeBSD/snapshots/</ulink>.</para>
<para>Snapshots are generated, on the average, daily for
all actively developed branches.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="stable">
<para>What is the FreeBSD-STABLE concept?</para>
</question>
<answer>
<para>Back when FreeBSD 2.0.5 was released, FreeBSD
development branched in two. One branch was named <ulink
url="&url.books.handbook;/current-stable.html#STABLE">-STABLE</ulink>,
one <ulink
url="&url.books.handbook;/current-stable.html#CURRENT">-CURRENT</ulink>.
FreeBSD-STABLE is intended for Internet Service Providers
and other commercial enterprises for whom sudden shifts or
experimental features are quite undesirable. It receives
only well-tested bug fixes and other small incremental
enhancements. FreeBSD-CURRENT, on the other hand, has
been one unbroken line since 2.0 was released, leading
towards 5.3-RELEASE (and beyond). Just before 5.3-RELEASE, the
5-STABLE branch was created, and
&os.current; became 6-CURRENT. For more detailed information,
see <quote><ulink url="&url.articles.releng;/release-proc.html#REL-BRANCH">
FreeBSD Release Engineering:
Creating the Release Branch</ulink></quote>.</para>
<para>The 2.2-STABLE branch was retired with the release of 2.2.8.
The 3-STABLE branch has ended with the release of 3.5.1, the
final 3.X release. The only changes made to either of these
branches will be, for the most part, security-related bug
fixes. Support for the 4-STABLE branch will continue
for some time but focus primarily on security-related bug
fixes and other serious issues.</para>
<para>5-STABLE is the actively developed -STABLE branch.
The latest release on the 5-STABLE branch is
&rel.current;-RELEASE, which was released in
&rel.current.date;.</para>
<para>The 6-CURRENT branch is the actively developed
-CURRENT branch toward the next generation of &os;.
See <link linkend="current">What is &os;-CURRENT?</link> for more
information on this branch.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="release-freq">
<para>When are FreeBSD releases made?</para>
</question>
<answer>
<para>The &a.re; releases a new version of FreeBSD about every
four months, on average. Release dates are announced well in
advance, so that the people working on the system know
when their projects need to be finished and tested.
A testing period precedes each release, in order to ensure
that the addition of new features does not compromise the
stability of the release.
Many users regard this caution as one of the best things about
FreeBSD, even though waiting for all the latest goodies to reach
-STABLE can be a little frustrating.</para>
<para>More information on the release engineering process
(including a schedule of upcoming releases) can be found
on the <ulink
url="http://www.FreeBSD.org/releng/index.html">release
engineering</ulink> pages on the FreeBSD Web site.</para>
<para>For people who need or want a little more excitement,
binary snapshots are made daily as discussed above.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="responsible">
<para>Who is responsible for FreeBSD?</para>
</question>
<answer>
<para>The key decisions concerning the FreeBSD project, such
as the overall direction of the project and who is allowed
to add code to the source tree, are made by a <ulink
url="&url.articles.contributors;/article.html#STAFF-CORE">core
team</ulink> of 9 people. There is a much larger team of
more than 300 <ulink
url="&url.articles.contributors;/article.html#STAFF-COMMITTERS">committers</ulink>
who are authorized to make changes directly to the FreeBSD
source tree.</para>
<para>However, most non-trivial changes are discussed in advance
in the <link linkend="mailing">mailing lists</link>, and there
are no restrictions on who may take part in the
discussion.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="where-get">
<para>Where can I get FreeBSD?</para>
</question>
<answer>
<para>Every significant release of FreeBSD is available via
anonymous FTP from the <ulink
url="ftp://ftp.FreeBSD.org/pub/FreeBSD/">
FreeBSD FTP site</ulink>:</para>
<itemizedlist>
<listitem>
<para>The latest 5-STABLE release, &rel.current;-RELEASE can be
found in the <ulink
url="ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/i386/&rel.current;-RELEASE/">&rel.current;-RELEASE directory</ulink>.</para>
</listitem>
<listitem>
<para><ulink
url="ftp://current.FreeBSD.org/pub/FreeBSD/">
Snapshot</ulink> releases are made daily for the
<link linkend="current">-CURRENT</link> branch, these being
of service purely to bleeding-edge testers and
developers.</para>
</listitem>
<listitem>
<para>The latest 4-STABLE release, &rel2.current;-RELEASE can be
found in the <ulink
url="ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/i386/&rel2.current;-RELEASE/">&rel2.current;-RELEASE directory</ulink>.</para>
</listitem>
<listitem>
<para><ulink
url="ftp://current.FreeBSD.org/pub/FreeBSD/snapshots/">5.X
snapshots</ulink> are usually made daily.</para>
</listitem>
</itemizedlist>
<para>Information about obtaining FreeBSD on CD, DVD, and other
media can be found in <ulink url="&url.books.handbook;/mirrors.html">the
Handbook</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="howto-mirror">
<para>How do I set up a FreeBSD mirror?</para>
</question>
<answer>
<para>Information on setting up a FreeBSD mirror can be
found in the <ulink url="&url.articles.hubs;/">Mirroring
FreeBSD</ulink> article.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="access-pr">
<para>How do I access the Problem Report database?</para>
</question>
<answer>
<para>The Problem Report database of all user change requests
may be queried by using our web-based PR
<ulink
url="http://www.FreeBSD.org/cgi/query-pr-summary.cgi?query">
query</ulink>
interface. The &man.send-pr.1; command can
be used to submit problem reports and change requests via
electronic mail.</para>
<para>The web-based problem report submission interface is
currently disabled due to persistent abuse.</para>
<para>Before submitting a problem report, please read <ulink
url="&url.articles.problem-reports;/article.html">Writing
FreeBSD Problem Reports</ulink>, an article on how to write
good problem reports.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="become-web-mirror">
<para>How do I become a FreeBSD Web mirror?</para>
</question>
<answer>
<para>There are multiple ways to mirror the Web pages.</para>
<itemizedlist>
<listitem>
<para>You can retrieve the formatted files from a
FreeBSD CVSup server using the application
<filename role="package">net/cvsup</filename>. The file
<filename>/usr/share/examples/cvsup/www-supfile</filename>
contains an example CVSup configuration file for web
mirrors.</para>
</listitem>
<listitem>
<para>You can download the web site source code from any
FreeBSD FTP server using your favorite ftp mirror
tool. Keep in mind that you have to build these
sources before publishing them. Start mirroring at
<ulink url="ftp://ftp.FreeBSD.org/pub/FreeBSD/FreeBSD-current/www/"></ulink>.</para>
</listitem>
</itemizedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="other-info-sources">
<para>What other sources of information are there?</para>
</question>
<answer>
<para>Please check the <ulink
url="http://www.FreeBSD.org/docs.html">Documentation</ulink>
list on the main <ulink
url="http://www.FreeBSD.org">FreeBSD</ulink> web
site.</para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter id="support">
<title>Documentation and Support</title>
<qandaset>
<qandaentry>
<question id="books">
<para>What good books are there about FreeBSD?</para>
</question>
<answer>
<para>The project produces a wide range of documentation,
available online from this link: <ulink
url="http://www.FreeBSD.org/docs.html"></ulink>. The same
documents are available as packages, that you can easily
install on your FreeBSD system. More details on
documentation packages can be found in the next
paragraphs.</para>
<para>In addition, the Bibliography at the end of this
FAQ, and the one in the Handbook reference other
recommended books.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="doc-formats">
<para>Is the documentation available in other formats, such as plain
text (ASCII), or &postscript;?</para>
</question>
<answer>
<para>Yes. The documentation is available in a number of
different formats and compression schemes on the FreeBSD
FTP site, in the <ulink
url="ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/">/pub/FreeBSD/doc/</ulink>
directory.</para>
<para>The documentation is categorized in a number of different
ways. These include:</para>
<itemizedlist>
<listitem>
<para>The document's name, such as <literal>faq</literal>, or
<literal>handbook</literal>.</para>
</listitem>
<listitem>
<para>The document's language and encoding. These are
based on the locale names you will find under
<filename>/usr/share/locale</filename> on your FreeBSD
system. The current languages and encodings that we
have for documentation are as follows:</para>
<informaltable frame="none" pgwide="1">
<tgroup cols="2">
<thead>
<row>
<entry>Name</entry>
<entry>Meaning</entry>
</row>
</thead>
<tbody>
<row>
<entry><literal>en_US.ISO8859-1</literal></entry>
<entry>US English</entry>
</row>
<row>
<entry><literal>de_DE.ISO8859-1</literal></entry>
<entry>German</entry>
</row>
<row>
<entry><literal>es_ES.ISO8859-1</literal></entry>
<entry>Spanish</entry>
</row>
<row>
<entry><literal>fr_FR.ISO8859-1</literal></entry>
<entry>French</entry>
</row>
<row>
<entry><literal>it_IT.ISO8859-15</literal></entry>
<entry>Italian</entry>
</row>
<row>
<entry><literal>ja_JP.eucJP</literal></entry>
<entry>Japanese (EUC encoding)</entry>
</row>
<row>
<entry><literal>ru_RU.KOI8-R</literal></entry>
<entry>Russian (KOI8-R encoding)</entry>
</row>
<row>
<entry><literal>zh_TW.Big5</literal></entry>
<entry>Chinese (Big5 encoding)</entry>
</row>
</tbody>
</tgroup>
</informaltable>
<note>
<para>Some documents may not be available in all
languages.</para>
</note>
</listitem>
<listitem>
<para>The document's format. We produce the documentation in a
number of different output formats. Each format has its own
advantages and disadvantages. Some formats are better suited
for online reading, while others are meant to be aesthetically
pleasing when printed on paper. Having the documentation
available in any of these formats ensures that our readers
will be able to read the parts they are interested in, either
on their monitor, or on paper after printing the documents.
The currently available formats are:</para>
<informaltable frame="none" pgwide="1">
<tgroup cols="2">
<thead>
<row>
<entry>Format</entry>
<entry>Meaning</entry>
</row>
</thead>
<tbody>
<row>
<entry><literal>html-split</literal></entry>
<entry>A collection of small, linked, HTML
files.</entry>
</row>
<row>
<entry><literal>html</literal></entry>
<entry>One large HTML file containing the entire
document</entry>
</row>
<row>
<entry><literal>pdb</literal></entry>
<entry>Palm Pilot database format, for use with the
<ulink url="http://www.iSilo.com/">iSilo</ulink>
reader.</entry>
</row>
<row>
<entry><literal>pdf</literal></entry>
<entry>Adobe's Portable Document Format</entry>
</row>
<row>
<entry><literal>ps</literal></entry>
<entry>&postscript;</entry>
</row>
<row>
<entry><literal>rtf</literal></entry>
<entry>Microsoft's Rich Text Format<footnote>
<para>Page numbers are not automatically
updated when loading this format into Word.
Press <keycombo
action="simul"><keycap>CTRL</keycap><keycap>A</keycap></keycombo>,
<keycombo
action="simul"><keycap>CTRL</keycap><keycap>END</keycap></keycombo>,
<keycap>F9</keycap> after loading the
document, to update the page numbers.</para>
</footnote>
</entry>
</row>
<row>
<entry><literal>txt</literal></entry>
<entry>Plain text</entry>
</row>
</tbody>
</tgroup>
</informaltable>
</listitem>
<listitem>
<para>The compression and packaging scheme. There are three of
these currently in use.</para>
<orderedlist>
<listitem>
<para>Where the format is
<literal>html-split</literal>, the files are
bundled up using &man.tar.1;. The resulting
<filename>.tar</filename> file is then compressed
using the compression schemes detailed in the next
point.</para>
</listitem>
<listitem>
<para>All the other formats generate one file,
called
<filename>book.<replaceable>format</replaceable></filename>
(i.e., <filename>book.pdb</filename>,
<filename>book.html</filename>, and so on).</para>
<para>These files are then compressed using two
compression schemes.</para>
<informaltable frame="none" pgwide="1">
<tgroup cols="2">
<thead>
<row>
<entry>Scheme</entry>
<entry>Description</entry>
</row>
</thead>
<tbody>
<row>
<entry><literal>zip</literal></entry>
<entry>The Zip format. If you want to
uncompress this on FreeBSD you will need
to install the <filename
role="package">archivers/unzip</filename>
port first.</entry>
</row>
<row>
<entry><literal>bz2</literal></entry>
<entry>The BZip2 format. Less widespread
than Zip, but generally gives
smaller files. Install the <filename
role="package">archivers/bzip2</filename>
port to uncompress these files.</entry>
</row>
</tbody>
</tgroup>
</informaltable>
<para>So the &postscript; version of the Handbook,
compressed using BZip2 will be stored in a file
called <filename>book.ps.bz2</filename> in the
<filename>handbook/</filename> directory.</para>
</listitem>
</orderedlist>
</listitem>
</itemizedlist>
<para>After choosing the format and compression mechanism that you
want to download, you must then decide whether or not you want to
download the document as a FreeBSD
<emphasis>package</emphasis>.</para>
<para>The advantage of downloading and installing the package is
that the documentation can then be managed using the normal
FreeBSD package management comments, such as &man.pkg.add.1; and
&man.pkg.delete.1;.</para>
<para>If you decide to download and install the package then
you must know the filename to download. The
documentation-as-packages files are stored in a directory
called <filename>packages</filename>. Each package file
looks like
<filename><replaceable>document-name</replaceable>.<replaceable>lang</replaceable>.<replaceable>encoding</replaceable>.<replaceable>format</replaceable>.tgz</filename>.</para>
<para>For example, the FAQ, in English, formatted as PDF, is in the
package called
<filename>faq.en_US.ISO8859-1.pdf.tgz</filename>.</para>
<para>Knowing this, you can use the following command to
install the English PDF FAQ package.</para>
<screen>&prompt.root; <userinput>pkg_add ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/packages/faq.en_US.ISO8859-1.pdf.tgz</userinput></screen>
<para>Having done that, you can use &man.pkg.info.1; to determine
where the file has been installed.</para>
<screen>&prompt.root; <userinput>pkg_info -f faq.en_US.ISO8859-1.pdf</userinput>
Information for faq.en_US.ISO8859-1.pdf:
Packing list:
Package name: faq.en_US.ISO8859-1.pdf
CWD to /usr/share/doc/en_US.ISO8859-1/books/faq
File: book.pdf
CWD to .
File: +COMMENT (ignored)
File: +DESC (ignored)</screen>
<para>As you can see, <filename>book.pdf</filename> will
have been installed into
<filename>/usr/share/doc/en_US.ISO8859-1/books/faq</filename>.</para>
<para>If you do not want to use the packages then you will have to
download the compressed files yourself, uncompress them, and then
copy the appropriate documents into place.</para>
<para>For example, the split HTML version of the FAQ,
compressed using &man.bzip2.1;, can be found in the
<filename>doc/en_US.ISO8859-1/books/faq/book.html-split.tar.bz2</filename>
file. To download and uncompress that file you would have
to do this.</para>
<screen>&prompt.root; <userinput>fetch ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/en_US.ISO8859-1/books/faq/book.html-split.tar.bz2</userinput>
&prompt.root; <userinput>bzip2 -d book.html-split.tar.bz2</userinput>
&prompt.root; <userinput>tar xvf book.html-split.tar</userinput></screen>
<para>You will be left with a collection of
<filename>.html</filename> files. The main one is called
<filename>index.html</filename>, which will contain the
table of contents, introductory material, and links to the
other parts of the document. You can then copy or move
these to their final location as necessary.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="mailing">
<para>Where do I find info on the FreeBSD mailing lists?</para>
</question>
<answer>
<para>You can find full information in the <ulink
url="&url.books.handbook;/eresources.html#ERESOURCES-MAIL">Handbook
entry on mailing-lists</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="y2k">
<para>Where do I find the FreeBSD Y2K info?</para>
</question>
<answer>
<para>You can find full information in the <ulink
url="&url.base;/y2kbug.html">FreeBSD Y2K page</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="newsgroups">
<para>What FreeBSD news groups are available?</para>
</question>
<answer>
<para>You can find full information in the <ulink
url="&url.books.handbook;/eresources-news.html">Handbook entry on
newsgroups</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="irc">
<para>Are there FreeBSD IRC (Internet Relay Chat)
channels?</para>
</question>
<answer>
<para>Yes, most major IRC networks host a FreeBSD chat
channel:</para>
<itemizedlist>
<listitem>
<para>Channel <literal>#FreeBSD</literal> on
<ulink url="http://www.efnet.org/index.php">EFNet</ulink>
is a FreeBSD forum, but do not go there for tech
support or try to get folks there to help you avoid
the pain of reading manual pages or doing your own research.
It is a chat channel, first and foremost, and topics there
are just as likely to involve sex, sports or nuclear
weapons as they are FreeBSD. You Have Been Warned!
Available at server <hostid>irc.chat.org</hostid>.</para>
</listitem>
<listitem>
<para>Channel <literal>#FreeBSDhelp</literal> on
<ulink url="http://www.efnet.org/index.php">EFNet</ulink>
is a channel dedicated to helping FreeBSD users. They
are much more sympathetic to questions than
<literal>#FreeBSD</literal> is.</para>
</listitem>
<listitem>
<para>Channel <literal>#FreeBSD</literal> on
<ulink url="http://www.dal.net/">DALNET</ulink>
is available at <hostid>irc.dal.net</hostid> in the
US and <hostid>irc.eu.dal.net</hostid> in Europe.</para>
</listitem>
<listitem>
<para>Channel <literal>#FreeBSD</literal> on
<ulink url="http://www.undernet.org/">UNDERNET</ulink>
is available at <hostid>us.undernet.org</hostid>
in the US and <hostid>eu.undernet.org</hostid> in Europe.
Since it is a help channel, be prepared to read the
documents you are referred to.</para>
</listitem>
<listitem>
<para>Channel <literal>#FreeBSD</literal> on <ulink
url="http://www.hybnet.net/">HybNet</ulink>. This channel
<emphasis>is</emphasis> a help channel. A list of servers
can be found on the <ulink
url="http://www.hybnet.net/">HybNet web site</ulink>.</para>
</listitem>
</itemizedlist>
<para>Each of these channels are distinct and are not
connected to each other. Their chat styles also differ,
so you may need to try each to find one suited to your
chat style. As with <emphasis>all</emphasis> types of IRC
traffic, if you are easily offended or cannot deal with
lots of young people (and more than a few older ones)
doing the verbal equivalent of jello wrestling, do not
even bother with it.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="training">
<para>Where can I get commercial FreeBSD training and support?</para>
</question>
<answer>
<para>DaemonNews provides commercial training and support for
FreeBSD. More information can be found at their
<ulink url="http://www.bsdmall.com/">BSD Mall</ulink>
site.</para>
<para>FreeBSD Services Ltd provide commercial support for FreeBSD
in the UK (as well as selling FreeBSD on DVD). See their
<ulink url="http://www.freebsd-services.com">web site</ulink>
for more information.</para>
<para>The FreeBSD Mall provides commercial FreeBSD support.
You can get more information at their <ulink
url="http://www.freebsdmall.com/">web site</ulink>.</para>
<para>Any other organizations providing training and support should
contact the project in order to be listed here.</para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter
id="install">
<chapterinfo>
<author>
<firstname>Nik</firstname>
<surname>Clayton</surname>
<affiliation>
<address><email>nik@FreeBSD.org</email></address>
</affiliation>
</author>
</chapterinfo>
<title>Installation</title>
<qandaset>
<qandaentry>
<question id="floppy-download">
<para>Which file do I download to get FreeBSD?</para>
</question>
<answer>
<para>For 4.X you need two floppy images:
<filename>floppies/kernel.flp</filename> and
<filename>floppies/mfsroot.flp</filename>. These images need to
be copied onto floppies by tools like
<command>fdimage</command> or &man.dd.1;.
In &os; 5.3 and later, the boot floppies have been restructured
and you need <filename>floppies/boot.flp</filename> and
all the <filename>floppies/kern<replaceable>X</replaceable></filename>
files (of which there are currently two).</para>
<para>If you need to download the distributions yourself (for a
DOS filesystem install, for instance), below are some
recommendations for distributions to grab:</para>
<itemizedlist>
<listitem>
<para>base/ (bin/ in 4.X)</para>
</listitem>
<listitem>
<para>manpages/</para>
</listitem>
<listitem>
<para>compat*/</para>
</listitem>
<listitem>
<para>doc/</para>
</listitem>
<listitem>
<para>src/ssys.*</para>
</listitem>
</itemizedlist>
<para>Full instructions on this procedure and a little bit more
about installation issues in general can be found in the
<ulink url="&url.books.handbook;/install.html">Handbook entry on
installing FreeBSD</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="floppy-image-too-large">
<para>What do I do if the floppy images does not fit on a single
floppy?</para>
</question>
<answer>
<para>A 3.5 inch (1.44MB) floppy can accommodate 1474560 bytes
of data. The boot image is exactly 1474560 bytes in size.</para>
<para>Common mistakes when preparing the boot floppy are:</para>
<itemizedlist>
<listitem>
<para>Not downloading the floppy image in
<emphasis>binary</emphasis> mode when using
<acronym>FTP</acronym>.</para>
<para>Some FTP clients default their transfer mode to
<emphasis>ascii</emphasis> and attempt to change any
end-of-line characters received to match the conventions
used by the client's system. This will almost invariably
corrupt the boot image. Check the size of the downloaded
boot image: if it is not <emphasis>exactly</emphasis> that
on the server, then the download process is suspect.</para>
<para>To workaround: type <emphasis>binary</emphasis> at the
FTP command prompt after getting connected to the server
and before starting the download of the image.</para>
</listitem>
<listitem>
<para>Using the DOS <command>copy</command> command (or
equivalent GUI tool) to transfer the boot image to
floppy.</para>
<para>Programs like <command>copy</command> will not work as
the boot image has been created to be booted into directly.
The image has the complete content of the floppy, track for
track, and is not meant to be placed on the floppy as a
regular file. You have to transfer it to the floppy
<quote>raw</quote>, using the low-level tools (e.g.
<command>fdimage</command> or <command>rawrite</command>)
described in the <ulink
url="&url.books.handbook;/install.html">installation guide to
FreeBSD</ulink>.</para>
</listitem>
</itemizedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="install-instructions-location">
<para>Where are the instructions for installing FreeBSD?</para>
</question>
<answer>
<para>Installation instructions can be found in the
<ulink url="&url.books.handbook;/install.html">Handbook entry on installing FreeBSD</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="need-to-run">
<para>What do I need in order to run FreeBSD?</para>
</question>
<answer>
<para>For versions prior to 5.X, you will need a 386 or better
PC, with 5 MB or more of RAM
and at least 60 MB of hard disk space. The &os;
installation process requires somewhat more memory so in
practice, 16 MB of RAM is a minimum requirement for a
standalone &os; system.</para>
<para>For &os; 5.X and later you will need a 486 or better
PC, with 24 MB or more of RAM and at least 150 MB of hard disk
space.</para>
<para>All versions of &os; can run with a low
end MDA graphics card but to run X11R6, a VGA or better video
card is needed.</para>
<para>See also <xref linkend="hardware">.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="four-meg-ram-install">
<para>I have only 4 MB of RAM. Can I install FreeBSD?</para>
</question>
<answer>
<para>FreeBSD 2.1.7 was the last version of FreeBSD that
could be installed on a 4MB system. FreeBSD 2.2 and later
needs at least 5MB, and &os; 5.X and later need at least 8MB to
install on a new system.</para>
<para>All versions of FreeBSD prior to 5.X will <emphasis>run</emphasis>
in 4MB of RAM, they just cannot run the installation
program in 4MB. You can add extra memory for the install
process, if you like, and then after the system is up and
running, go back to 4MB. Or you could swap your disk into
a system which has &gt;4MB, install onto the disk and then
swap it back.</para>
<para>After the installation, if you build a custom kernel,
it will run in 4 MB. Someone has even successfully booted
with 2 MB, although the system was almost unusable.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="custom-boot-floppy">
<para>How can I make my own custom install floppy?</para>
</question>
<answer>
<para>Currently there is no way to <emphasis>just</emphasis>
make a custom install floppy. You have to cut a whole new
release, which will include your install floppy.</para>
<para>To make a custom release, follow the instructions in the
<ulink url="&url.articles.releng;/article.html">Release
Engineering</ulink> article.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="multiboot">
<para>Can I have more than one operating system on my PC?</para>
</question>
<answer>
<para>Have a look at
<ulink url="&url.articles.multi-os;/index.html">
the multi-OS page</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="windows-coexist">
<para>Can &windows; co-exist with FreeBSD?</para>
</question>
<answer>
<para>Install &windows; first, then FreeBSD.
FreeBSD's boot manager will then manage to boot &windows; and
FreeBSD. If you install &windows; second, it will boorishly
overwrite your boot manager without even asking. If that
happens, see the next section.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="win95-damaged-boot-manager">
<para>&windows; killed my boot manager!
How do I get it back?</para>
</question>
<answer>
<para>You can reinstall the boot manager FreeBSD comes with in
one of three ways:</para>
<itemizedlist>
<listitem>
<para>Running DOS, go into the tools/ directory of your
FreeBSD distribution and look for
<filename>bootinst.exe</filename>. You run it like
so:</para>
<screen><prompt>...\TOOLS&gt;</prompt> <userinput>bootinst.exe boot.bin</userinput></screen>
<para>and the boot manager will be reinstalled.</para>
</listitem>
<listitem>
<para>Boot the FreeBSD boot floppy again and go to the
Custom installation menu item. Choose Partition. Select the
drive which used to contain your boot manager (likely the
first one) and when you come to the partition editor for
it, as the very first thing (e.g. do not make any changes)
select (W)rite. This will ask for confirmation, say yes,
and when you get the Boot Manager selection prompt, be
sure to select <quote>Boot Manager</quote>. This will
re-write the boot manager to disk. Now quit out of the
installation menu and reboot off the hard disk as
normal.</para>
</listitem>
<listitem>
<para>Boot the FreeBSD boot floppy (or CDROM) and choose the
<quote>Fixit</quote> menu item. Select either the Fixit
floppy or CDROM #2 (the <quote>live</quote> filesystem
option) as appropriate and enter the fixit shell. Then
execute the following command:</para>
<screen><prompt>Fixit#</prompt> <userinput>fdisk -B -b /boot/boot0 <replaceable>bootdevice</replaceable></userinput></screen>
<para>substituting <replaceable>bootdevice</replaceable> for
your real
boot device such as <devicename>ad0</devicename> (first IDE
disk), <devicename>ad4</devicename> (first IDE disk on
auxiliary controller), <devicename>da0</devicename> (first
SCSI disk), etc.</para>
</listitem>
</itemizedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="boot-on-thinkpad">
<para>My A, T, or X series IBM Thinkpad locks up when I first
booted up my FreeBSD installation. How can I solve this?</para>
</question>
<answer>
<para>A bug in early revisions of IBM's BIOS on these machines
mistakenly identifies the FreeBSD partition as a potential FAT
suspend-to-disk partition. When the BIOS tries to parse the
FreeBSD partition it hangs.</para>
<para>According to IBM<footnote><para>In an e-mail from Keith
Frechette
<email>kfrechet@us.ibm.com</email>.</para></footnote>, the
following model/BIOS release numbers incorporate the fix.</para>
<informaltable frame="none" pgwide="1">
<tgroup cols="2">
<thead>
<row>
<entry>Model</entry>
<entry>BIOS revision</entry>
</row>
</thead>
<tbody>
<row>
<entry>T20</entry>
<entry>IYET49WW or later</entry>
</row>
<row>
<entry>T21</entry>
<entry>KZET22WW or later</entry>
</row>
<row>
<entry>A20p</entry>
<entry>IVET62WW or later</entry>
</row>
<row>
<entry>A20m</entry>
<entry>IWET54WW or later</entry>
</row>
<row>
<entry>A21p</entry>
<entry>KYET27WW or later</entry>
</row>
<row>
<entry>A21m</entry>
<entry>KXET24WW or later</entry>
</row>
<row>
<entry>A21e</entry>
<entry>KUET30WW</entry>
</row>
</tbody>
</tgroup>
</informaltable>
<para>It has been reported that later IBM BIOS revisions may
have reintroduced the bug. <ulink
url="http://docs.FreeBSD.org/cgi/mid.cgi?20010427133759.A71732">This
message</ulink> from Jacques Vidrine to the &a.mobile;
describes a procedure which may work if your newer IBM
laptop does not boot FreeBSD properly, and you can upgrade
or downgrade the BIOS.</para>
<para>If you have an earlier BIOS, and upgrading is not an option, a
workaround is to install FreeBSD, change the partition ID FreeBSD
uses, and install new boot blocks that can handle the different
partition ID.</para>
<para>First, you will need to restore the machine to a state where
it can get through its self-test screen. Doing this requires
powering up the machine without letting it find a FreeBSD
partition on its primary disk. One way is to remove the hard disk
and temporarily move it to an older ThinkPad (such as a ThinkPad
600) or a desktop PC with an appropriate conversion cable. Once
it is there, you can delete the FreeBSD partition and move the hard
disk back. The ThinkPad should now be in a bootable state
again.</para>
<para>With the machine functional again, you can use the workaround
procedure described here to get a working FreeBSD
installation.</para>
<procedure>
<step>
<para>Download <filename>boot1</filename> and
<filename>boot2</filename> from <ulink
url="http://people.FreeBSD.org/~bmah/ThinkPad/"></ulink>.
Put these files somewhere you will be able to retrieve them
later.</para>
</step>
<step>
<para>Install FreeBSD as normal on to the ThinkPad.
<emphasis>Do not</emphasis> use <literal>Dangerously
Dedicated</literal> mode. <emphasis>Do not</emphasis>
reboot when the install has finished.</para>
</step>
<step>
<para>Either switch to the <quote>Emergency Holographic
Shell</quote> (<keycombo action="simul"><keycap>ALT</keycap>
<keycap>F4</keycap></keycombo>) or start a
<quote>fixit</quote> shell.</para>
</step>
<step>
<para>Use &man.fdisk.8; to change the FreeBSD partition ID from
<literal>165</literal> to <literal>166</literal> (this is the
type used by OpenBSD).</para>
</step>
<step>
<para>Bring the <filename>boot1</filename> and
<filename>boot2</filename> files to the local
filesystem.</para>
</step>
<step>
<para>Use &man.disklabel.8; to write <filename>boot1</filename>
and <filename>boot2</filename> to your FreeBSD slice.</para>
<screen>&prompt.root; <userinput>disklabel -B -b boot1 -s boot2 ad0s<replaceable>n</replaceable></userinput></screen>
<para><replaceable>n</replaceable> is the number of the slice
where you installed FreeBSD.</para>
</step>
<step>
<para>Reboot. At the boot prompt you will be given the option
of booting <literal>OpenBSD</literal>. This will actually
boot FreeBSD.</para>
</step>
</procedure>
<para>Getting this to work in the case where you want to dual boot
OpenBSD and FreeBSD on the same laptop is left as an exercise for
the reader.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="install-bad-blocks">
<para>Can I install on a disk with bad blocks?</para>
</question>
<answer>
<para>You can, but it is a bad idea.</para>
<para>If you are seeing bad block errors with a modern IDE
drive, chances are the drive is going to die very soon (the
drive's internal remapping functions are no longer sufficient
to fix the bad blocks, which means the disk is heavily
corrupted); we suggest you buy a new hard drive.</para>
<para>If you have a SCSI drive with bad blocks, see
<link linkend="awre">this answer</link>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="bad144-3x-4x">
<para>I have just upgraded from 3.X to 4.X, and my first boot
failed with <errorname>bad sector table not
supported</errorname></para>
</question>
<answer>
<para>FreeBSD 3.X and earlier supported
<command>bad144</command>, which automatically remapped
bad blocks. FreeBSD 4.X and later do not support this, as
modern IDE drives include this functionality. See <link
linkend="install-bad-blocks">this question</link> for
more information.</para>
<para>To fix this after an upgrade, you need to physically
place the drive in a working system and use
&man.disklabel.8; as discussed in the following
questions.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="find-bad144">
<para>How do I tell if a drive has <command>bad144</command>
information on it before I try to upgrade to FreeBSD 4.0
and it fails?</para>
</question>
<answer>
<para>Use &man.disklabel.8; for this. <command>disklabel -r
<replaceable>drive device</replaceable></command> will
give you the contents of your disk label. Look for a
<literal>flags</literal> field. If you see
<literal>flags: badsect</literal>, this drive is using
bad144. For example, the following drive has
<command>bad144</command> enabled.:</para>
<screen>&prompt.root; <userinput>disklabel -r wd0</userinput>
# /dev/rwd0c:
type: ESDI
disk: wd0s1
label:
flags: badsect
bytes/sector: 512
sectors/track: 63</screen>
</answer>
</qandaentry>
<qandaentry>
<question id="disable-bad144">
<para>How do I remove <command>bad144</command> from my
pre-4.X system so I can upgrade safely?</para>
</question>
<answer>
<para>Use <command>disklabel -e -rwd0 </command> to edit the
disklabel in place. Just remove the word
<literal>badsect</literal> from the flags field, save, and
exit. The bad144 file will still take up some space on
your drive, but the disk itself will be usable.</para>
<para>We still recommend you purchase a new disk if you have
a large number of bad blocks.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="boot-floppy-strangeness">
<para>Strange things happen when I boot the install floppy!
What is happening?</para>
</question>
<answer>
<para>If you are seeing things like the machine grinding to a halt
or spontaneously rebooting when you try to boot the install
floppy, here are three questions to ask yourself:-</para>
<orderedlist>
<listitem>
<para>Did you use a new, freshly-formatted, error-free floppy
(preferably a brand-new one straight out of the box, as
opposed to the magazine cover disk that has been lying under
the bed for the last three years)?</para>
</listitem>
<listitem>
<para>Did you download the floppy image in binary (or image)
mode? (do not be embarrassed, even the best of us have
accidentally downloaded a binary file in ASCII mode at
least once!)</para>
</listitem>
<listitem>
<para>If you are using &windows; 95 or 98 did you run
<command>fdimage</command> or
<command>rawrite</command> in pure DOS mode? These
operating systems can interfere with programs that
write directly to hardware, which the disk creation
program does; even running it inside a DOS shell in
the GUI can cause this problem.</para>
</listitem>
</orderedlist>
<para>There have also been reports of &netscape; causing problems
when downloading the boot floppy, so it is probably best to use
a different FTP client if you can.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="no-install-cdrom">
<para>I booted from my ATAPI CDROM, but the install program
says no CDROM is found. Where did it go?</para>
</question>
<answer>
<para>The usual cause of this problem is a mis-configured CDROM
drive. Many PCs now ship with the CDROM as the slave device on
the secondary IDE controller, with no master device on that
controller. This is illegal according to the ATAPI specification,
but &windows; plays fast and loose with the specification, and the
BIOS ignores it when booting. This is why the BIOS was able to
see the CDROM to boot from it, but why FreeBSD cannot see it to
complete the install.</para>
<para>Reconfigure your system so that the CDROM is either the
master device on the IDE controller it is attached to, or make
sure that it is the slave on an IDE controller that also has a
master device.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="install-PLIP">
<para>Can I install on my laptop over PLIP (Parallel Line
IP)?</para>
</question>
<answer>
<para>Yes. Use a standard Laplink cable. If necessary, you
can check out the <ulink url="&url.books.handbook;/network-plip.html">PLIP
section of the Handbook</ulink> for details on parallel
port networking.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="geometry">
<para>Which geometry should I use for a disk drive?</para>
</question>
<answer>
<note>
<para>By the <quote>geometry</quote> of a disk, we mean
the number of cylinders, heads and sectors/track on a
disk. We will refer to this as C/H/S for
convenience. This is how the PC's BIOS works out which
area on a disk to read/write from.</para>
</note>
<para>This causes a lot of confusion among new system
administrators. First of all, the
<emphasis>physical</emphasis> geometry of a SCSI drive is
totally irrelevant, as FreeBSD works in term of disk
blocks. In fact, there is no such thing as
<quote>the</quote> physical geometry, as the sector
density varies across the disk. What manufacturers claim
is the <quote>physical geometry</quote> is usually the
geometry that they have determined wastes the least
space. For IDE disks, FreeBSD does work in terms of C/H/S,
but all modern drives internally convert this into block
references.</para>
<para>All that matters is the <emphasis>logical</emphasis>
geometry. This is the answer that the BIOS gets when it
asks the drive <quote>what is your geometry?</quote> It
then uses this geometry to access the disk. As FreeBSD
uses the BIOS when booting, it is very important to get
this right. In particular, if you have more than one
operating system on a disk, they must all agree on the
geometry. Otherwise you will have serious problems
booting!</para>
<para>For SCSI disks, the geometry to use depends on whether
extended translation support is turned on in your
controller (this is often referred to as <quote>support for
DOS disks &gt;1GB</quote> or something similar). If it is
turned off, then use <replaceable>N</replaceable>
cylinders, 64 heads and 32 sectors/track, where
<replaceable>N</replaceable> is the capacity of the disk in
MB. For example, a 2GB disk should pretend to have 2048
cylinders, 64 heads and 32 sectors/track.</para>
<para>If it <emphasis>is</emphasis> turned on (it is often
supplied this way to get around certain limitations in
&ms-dos;) and the disk capacity is more than 1GB, use M
cylinders, 63 sectors per track (<emphasis>not</emphasis>
64), and 255 heads, where <literal>M</literal> is the disk capacity in MB
divided by 7.844238 (!). So our example 2GB drive would
have 261 cylinders, 63 sectors per track and 255
heads.</para>
<para>If you are not sure about this, or FreeBSD fails to
detect the geometry correctly during installation, the
simplest way around this is usually to create a small DOS
partition on the disk. The BIOS should then detect the
correct geometry, and you can always remove the DOS
partition in the partition editor if you do not want to
keep it. You might want to leave it around for
programming network cards and the like, however.</para>
<para>Alternatively, there is a freely available utility
distributed with FreeBSD called
<filename>pfdisk.exe</filename>. You can find it in the
<filename>tools</filename> subdirectory on the FreeBSD
CDROM or on the various FreeBSD FTP sites. This program
can be used to work out what geometry the other operating
systems on the disk are using. You can then enter this
geometry in the partition editor.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="disk-divide-restrictions">
<para>Are there any restrictions on how I divide the disk up?</para>
</question>
<answer>
<para>Yes. You must make sure that your root partition is below 1024
cylinders so the BIOS can boot the kernel from it. (Note that
this is a limitation in the PC's BIOS, not FreeBSD).</para>
<para>For a SCSI drive, this will normally imply that the root
partition will be in the first 1024MB (or in the first 4096MB
if extended translation is turned on - see previous question).
For IDE, the corresponding figure is 504MB.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="disk-manager">
<para>Is FreeBSD compatible with any disk managers?</para>
</question>
<answer>
<para>FreeBSD recognizes the Ontrack Disk Manager and makes
allowances for it. Other disk managers are not supported.</para>
<para>If you just want to use the disk with FreeBSD you do not
need a disk manager. Just configure the disk for as much space
as the BIOS can deal with (usually 504 megabytes), and FreeBSD
should figure out how much space you really have. If you are
using an old disk with an MFM controller, you may need to
explicitly tell FreeBSD how many cylinders to use.</para>
<para>If you want to use the disk with FreeBSD and another
operating system, you may be able to do without a disk manager:
just make sure the FreeBSD boot partition and the slice for
the other operating system are in the first 1024 cylinders. If
you are reasonably careful, a 20 megabyte boot partition should
be plenty.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="missing-os">
<para>When I boot FreeBSD for the first time after install I get <errorname>Missing Operating
System</errorname>. What is happening?</para>
</question>
<answer>
<para>This is classically a case of FreeBSD and DOS or some other
OS conflicting over their ideas of disk <link
linkend="geometry">geometry</link>. You will have to reinstall
FreeBSD, but obeying the instructions given above will almost
always get you going.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="stop-at-boot-manager">
<para>Why can I not get past the boot manager's <prompt>F?</prompt>
prompt?</para>
</question>
<answer>
<para>This is another symptom of the problem described in the
preceding question. Your BIOS geometry and FreeBSD geometry
settings do not agree! If your controller or BIOS supports
cylinder translation (often marked as <quote>&gt;1GB drive
support</quote>), try toggling its setting and reinstalling
FreeBSD.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="need-complete-sources">
<para>Do I need to install the complete sources?</para>
</question>
<answer>
<para>In general, no. However, we would strongly recommend that
you install, at a minimum, the <literal>base</literal> source
kit, which includes several of the files mentioned here, and
the <literal>sys</literal> (kernel) source kit, which includes
sources for the kernel. There is nothing in the system which
requires the presence of the sources to operate, however,
except for the kernel-configuration program &man.config.8;.
With the exception of the kernel sources, our build structure
is set up so that you can read-only mount the sources from
elsewhere via NFS and still be able to make new binaries
(due to the kernel-source restriction, we recommend that
you not mount this on <filename>/usr/src</filename> directly,
but rather in some other location with appropriate symbolic
links to duplicate the top-level structure of the source
tree).</para>
<para>Having the sources on-line and knowing how to build a
system with them will make it much easier for you to upgrade
to future releases of FreeBSD.</para>
<para>To actually select a subset of the sources, use the Custom
menu item when you are in the Distributions menu of the
system installation tool.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="need-kernel">
<para>Do I need to build a kernel?</para>
</question>
<answer>
<para>Building a new kernel was originally pretty much a required
step in a FreeBSD installation, but more recent releases have
benefited from the introduction of much friendlier kernel
configuration methods. In 4.X and earlier, when at the FreeBSD boot prompt (boot:),
use the <option>-c</option> flag and you will be dropped into a
visual configuration screen which allows you to configure the
kernel's settings for most common ISA cards. In &os; 5.X and later
this has been replaced by much more flexible "hints" which
can be set from the loader prompt.</para>
<para>It may still be worthwhile building a new
kernel containing just the drivers that you need, just to save a
bit of RAM, but it is no longer necessary for most
systems.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="password-encryption">
<para>Should I use DES, Blowfish, or MD5 passwords and how
do I specify which form my users receive?</para>
</question>
<answer>
<para>The default password format on FreeBSD is to use
<emphasis>MD5</emphasis>-based passwords. These are
believed to be more secure than the traditional &unix;
password format, which used a scheme based on the
<emphasis>DES</emphasis> algorithm. DES passwords are
still available if you need to share your password file
with legacy operating systems which still use the less
secure password format (they are available if you choose
to install the <quote>crypto</quote> distribution in
sysinstall, or by installing the crypto sources if
building from source). Installing the crypto libraries
will also allow you to use the Blowfish password format,
which is more secure. Which password format to use for
new passwords is controlled by the
<quote>passwd_format</quote> login capability in
<filename>/etc/login.conf</filename>, which takes values
of <quote>des</quote>, <quote>blf</quote> (if these are
available) or <quote>md5</quote>. See the
&man.login.conf.5; manual page for more information about
login capabilities.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="boot-floppy-hangs">
<para>Why does the boot floppy start, but hang at the
<literal>Probing Devices...</literal> screen?</para>
</question>
<answer>
<para>If you have a IDE &iomegazip; or &jaz; drive installed, remove it
and try again. The boot floppy can get confused by the drives.
After the system is installed you can reconnect the drive.
Hopefully this will be fixed in a later release.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="panic-on-install-reboot">
<para>Why do I get a <errorname>panic: can't mount root</errorname>
error when rebooting the system after installation?</para>
</question>
<answer>
<para>This error comes from confusion between the boot block's
and the kernel's understanding of the disk devices. The error
usually manifests on two-disk IDE systems, with the hard disks
arranged as the master or single device on separate IDE
controllers, with FreeBSD installed on the secondary IDE
controller. The boot blocks think the system is installed on
wd1 (the second BIOS disk) while the kernel assigns the first
disk on the secondary controller device wd2. After the device
probing, the kernel tries to mount what the boot blocks think
is the boot disk, wd1, while it is really wd2, and
fails.</para>
<para>To fix the problem, do one of the following:</para>
<orderedlist>
<listitem>
<para>For FreeBSD 3.3 and later, reboot the system and hit
<keycap>Enter</keycap> at the <literal>Booting kernel
in 10 seconds; hit [Enter] to interrupt</literal> prompt.
This will drop you into the boot loader.</para>
<para>Then type
<literal>
set root_disk_unit="<replaceable>disk_number</replaceable>"
</literal>. <replaceable>disk_number</replaceable>
will be <literal>0</literal> if FreeBSD is installed on
the master drive on the first IDE controller,
<literal>1</literal> if it is installed on the slave on
the first IDE controller, <literal>2</literal> if it is
installed on the master of the second IDE controller, and
<literal>3</literal> if it is installed on the slave of
the second IDE controller.</para>
<para>Then type <literal>boot</literal>, and your system
should boot correctly.</para>
<para>To make this change permanent (ie so you do not
have to do this every time you reboot or turn on
your FreeBSD machine), put the line <literal>
root_disk_unit="<replaceable>disk_number</replaceable>"</literal>
in <filename>/boot/loader.conf.local
</filename>.</para>
</listitem>
<listitem>
<para>If using FreeBSD 3.2 or earlier, at the Boot:
prompt, enter <literal>1:wd(2,a)kernel</literal> and
press <keycap>Enter</keycap>. If the system starts,
then run the command <command>echo "1:wd(2,a)kernel"
&gt; /boot.config</command> to make it the default
boot string.</para>
</listitem>
<listitem>
<para>Move the FreeBSD disk onto the primary IDE controller,
so the hard disks are consecutive.</para>
</listitem>
<listitem>
<para><ulink url="&url.books.handbook;/kernelconfig.html">Rebuild
your kernel,</ulink> modify the wd configuration lines to
read:</para>
<programlisting>controller wdc0 at isa? port "IO_WD1" bio irq 14 vector wdintr
disk wd0 at wdc0 drive 0
# disk wd1 at wdc0 drive 1 # comment out this line
controller wdc1 at isa? port "IO_WD2" bio irq 15 vector wdintr
disk wd1 at wdc1 drive 0 # change from wd2 to wd1
disk wd2 at wdc1 drive 1 # change from wd3 to wd2</programlisting>
<para>Install the new kernel. If you moved your disks and
wish to restore the previous configuration, replace the
disks in the desired configuration and reboot. Your
system should boot successfully.</para>
</listitem>
</orderedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="memory-limits">
<para>What are the limits for memory?</para>
</question>
<answer>
<para>The limit is 4 gigabytes on a standard &i386; install.
Beginning with &os; versions 4.9 and 5.1, more memory can be
supported through &man.pae.4;. This does require a kernel
recompile, with an extra option to enable PAE:</para>
<programlisting>options PAE</programlisting>
<para>&os;/pc98 has a limit of 4 GB memory, and PAE can not
be used with it. On &os;/alpha, the limit on memory depends
on the type of hardware in use - consult the Alpha Hardware
Release Notes for details. Other architectures
supported by &os; have much higher theoretical limits on
maximum memory (many terabytes).</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ffs-limits">
<para>What are the limits for ffs filesystems?</para>
</question>
<answer>
<para>For ffs filesystems, the maximum theoretical limit is 8
terabytes (2G blocks), or 16TB for the default block size of
8K. In practice, there is a soft limit of 1 terabyte, but with
modifications filesystems with 4 terabytes are possible (and
exist).</para>
<para>The maximum size of a single ffs file is approximately 1G
blocks, or 4TB with a block size of 4K.</para>
<table>
<title>Maximum file sizes</title>
<tgroup cols="5">
<thead>
<row>
<entry>fs block size</entry>
<entry>2.2.7-stable</entry>
<entry>3.0-current</entry>
<entry>works</entry>
<entry>should work</entry>
</row>
</thead>
<tbody>
<row>
<entry>4K</entry>
<entry>4T-1</entry>
<entry>4T-1</entry>
<entry>4T-1</entry>
<entry>&gt;4T</entry>
</row>
<row>
<entry>8K</entry>
<entry>&gt;32G</entry>
<entry>8T-1</entry>
<entry>&gt;32G</entry>
<entry>32T-1</entry>
</row>
<row>
<entry>16K</entry>
<entry>&gt;128G</entry>
<entry>16T-1</entry>
<entry>&gt;128G</entry>
<entry>32T-1</entry>
</row>
<row>
<entry>32K</entry>
<entry>&gt;512G</entry>
<entry>32T-1</entry>
<entry>&gt;512G</entry>
<entry>64T-1</entry>
</row>
<row>
<entry>64K</entry>
<entry>&gt;2048G</entry>
<entry>64T-1</entry>
<entry>&gt;2048G</entry>
<entry>128T-1</entry>
</row>
</tbody>
</tgroup>
</table>
<para>When the fs block size is 4K, triple indirect blocks work
and everything should be limited by the maximum fs block number
that can be represented using triple indirect blocks (approx.
1K^3 + 1K^2 + 1K), but everything is limited by a (wrong) limit
of 1G-1 on fs block numbers. The limit on fs block numbers
should be 2G-1. There are some bugs for fs block numbers near
2G-1, but such block numbers are unreachable when the fs block
size is 4K.</para>
<para>For block sizes of 8K and larger, everything should be
limited by the 2G-1 limit on fs block numbers, but is actually
limited by the 1G-1 limit on fs block numbers, except under
-STABLE triple indirect blocks are unreachable, so the limit is
the maximum fs block number that can be represented using
double indirect blocks (approx. (blocksize/4)^2 +
(blocksize/4)), and under -CURRENT exceeding this limit may
cause problems. Using the correct limit of 2G-1 blocks does
cause problems.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="archsw-readin-failed-error">
<para>Why do I get an error message,
<errorname>archsw.readin.failed</errorname> after compiling
and booting a new kernel?</para>
</question>
<answer>
<para>You can boot by specifying the kernel directly at the second
stage, pressing any key when the | shows up before loader is
started. More specifically, you have upgraded the source for
your kernel, and installed a new kernel builtin from them
<emphasis>without making world</emphasis>. This is not
supported. Make world.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="security-profiles">
<para>What are these <quote>security profiles</quote>?</para>
</question>
<answer>
<para>A <quote>security profile</quote> is a set of configuration
options that attempts to achieve the desired ratio of security
to convenience by enabling and disabling certain programs and
other settings. For full details, see the <ulink
url="&url.books.handbook;/install-post.html#SECURITYPROFILE">Security
Profile</ulink> section of the Handbook's <ulink
url="&url.books.handbook;/install-post.html">post-install
chapter</ulink>.</para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter
id="hardware">
<title>Hardware compatibility</title>
<sect1 id="compatibility-general">
<title>General</title>
<qandaset>
<qandaentry>
<question id="which-hardware-to-get">
<para>I want to get a piece of hardware for my FreeBSD
system. Which model/brand/type is best?</para>
</question>
<answer>
<para>This is discussed continually on the FreeBSD mailing
lists. Since hardware changes so quickly, however, we
expect this. We <emphasis>still</emphasis> strongly
recommend that you read through the Hardware notes for &os;
<ulink url="&rel.current.hardware;">&rel.current;</ulink>
or
<ulink url="&rel2.current.hardware;">&rel2.current;</ulink>
and search the mailing list
<ulink url="http://www.FreeBSD.org/search/#mailinglists">
archives</ulink> before asking about the latest and
greatest hardware. Chances are a discussion about the
type of hardware you are looking for took place just last
week.</para>
<para>If you are looking for a laptop, check the
FreeBSD-mobile mailing list archives. Otherwise, you
probably want the archives for FreeBSD-questions, or
possibly a specific mailing list for a particular hardware
type.</para>
</answer>
</qandaentry>
</qandaset>
</sect1>
<sect1 id="compatibility-processors">
<title>Architectures and processors</title>
<qandaset>
<qandaentry>
<question id="architectures">
<para>Does FreeBSD support architectures other than the x86?</para>
</question>
<answer>
<para>Yes. FreeBSD currently runs on the Intel x86 and DEC (now
Compaq) Alpha architectures. As of FreeBSD 5.0, the
AMD64 and Intel EM64T, IA-64, and &sparc64; architectures are also
supported.
Upcoming platforms are
&mips; and &powerpc;, join the &a.ppc; or the
&a.mips; respectively for more information about ongoing
work on these platforms. For general discussion on new
architectures, join the &a.platforms;.</para>
<para>If your machine has a different architecture and you need
something right now, we suggest you look at <ulink
url="http://www.netbsd.org/">NetBSD</ulink> or <ulink
url="http://www.openbsd.org/">OpenBSD</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="smp-support">
<para>Does FreeBSD support Symmetric Multiprocessing
(SMP)?</para>
</question>
<answer>
<para>Yes. SMP was enabled by default in the
<emphasis>GENERIC</emphasis> kernel as of &os; 5.2.</para>
<para>The intention was also to enable it by default for
the &os; 5.3 release, but problems running the SMP kernel
on certain UP machines led to the decision to disable it
until those problems can be addressed. This is a priority
for &os; 5.4.</para>
<para>In &os; 4.X, SMP is not enabled in the default kernel,
so you must recompile your kernel to enable SMP. Take a
look at <filename>/sys/i386/conf/LINT</filename> to learn
which options to put in your kernel config file.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="no-math-coprocessor">
<para>I do not have a math co-processor - is that bad?</para>
</question>
<answer>
<note>
<para>This will only affect 386/486SX/486SLC owners - other
machines will have one built into the CPU.</para>
</note>
<para>In general this will not cause any problems, but there are
circumstances where you will take a hit, either in performance
or accuracy of the math emulation code (see the section <link
linkend="emul">on FP emulation</link>). In particular, drawing
arcs in X will be VERY slow. It is highly recommended that you
buy a math co-processor; it is well worth it.</para>
<note>
<para>Some math co-processors are better than others. It
pains us to say it, but nobody ever got fired for buying
Intel. Unless you are sure it works with FreeBSD, beware of
clones.</para>
</note>
</answer>
</qandaentry>
</qandaset>
</sect1>
<sect1 id="compatibility-drives">
<title>Hard drives, tape drives, and CD and DVD drives</title>
<qandaset>
<qandaentry>
<question id="supported-hard-drives">
<para>What kind of hard drives does FreeBSD support?</para>
</question>
<answer>
<para>FreeBSD supports EIDE and SCSI drives (with a compatible
controller; see the next section), and all drives using the
original <quote>Western Digital</quote> interface (MFM, RLL,
ESDI, and of course IDE). A few ESDI controllers that use
proprietary interfaces may not work: stick to WD1002/3/6/7
interfaces and clones.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="supported-scsi-controllers">
<para>Which SCSI controllers are supported?</para>
</question>
<answer>
<para>See the complete list in the Hardware Notes for &os;
<ulink url="&rel.current.hardware;">&rel.current;</ulink> or
<ulink url="&rel2.current.hardware;">&rel2.current;</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="tape-support">
<para>What types of tape drives are supported?</para>
</question>
<answer>
<para>FreeBSD supports SCSI and QIC-36 (with a QIC-02 interface).
This includes 8-mm (aka Exabyte) and DAT drives.</para>
<para>Some of the early 8-mm drives are not quite compatible
with SCSI-2, and may not work well with FreeBSD.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="tape-changer-support">
<para>Does FreeBSD support tape changers?</para>
</question>
<answer>
<para>FreeBSD supports SCSI changers using the &man.ch.4;
device and the &man.chio.1; command. The details of how you
actually control the changer can be found in the &man.chio.1;
manual page.</para>
<para>If you are not using <application>AMANDA</application>
or some other product that already understands changers,
remember that they only know how to move a tape from one
point to another, so you need to keep track of which slot a
tape is in, and which slot the tape currently in the drive
needs to go back to.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="supported-cdrom-drives">
<para>Which CDROM drives are supported by FreeBSD?</para>
</question>
<answer>
<para>Any SCSI drive connected to a supported controller is
supported.</para>
<para>The following proprietary CDROM interfaces are also
supported:</para>
<itemizedlist>
<listitem>
<para>Mitsumi LU002 (8bit), LU005 (16bit) and FX001D
(16bit 2x Speed).</para>
</listitem>
<listitem>
<para>Sony CDU 31/33A</para>
</listitem>
<listitem>
<para>Sound Blaster Non-SCSI CDROM</para>
</listitem>
<listitem>
<para>Matsushita/Panasonic CDROM</para>
</listitem>
<listitem>
<para>ATAPI compatible IDE CDROMs</para>
</listitem>
</itemizedlist>
<para>All non-SCSI cards are known to be extremely slow compared
to SCSI drives, and some ATAPI CDROMs may not work.</para>
<para>The official FreeBSD CDROM ISO, and CDROMs from Daemon
News and FreeBSD Mall, support booting directly from the
CD.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="supported-cdrw-drives">
<para>Which CD-RW drives are supported by FreeBSD?</para>
</question>
<answer>
<para>FreeBSD supports any ATAPI-compatible IDE CD-R or CD-RW
drive. For FreeBSD versions 4.0 and later, see the manual page for
&man.burncd.8;. For earlier FreeBSD versions, see the examples
in <filename>/usr/share/examples/atapi</filename>.</para>
<para>FreeBSD also supports any SCSI CD-R or CD-RW drives.
Install and use the <command>cdrecord</command> command from the
ports or packages system, and make sure that you have the
<devicename>pass</devicename> device compiled in your
kernel.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="zip-support">
<para>Does FreeBSD support &iomegazip; drives?</para>
</question>
<answer>
<para>FreeBSD supports SCSI and ATAPI (IDE) &iomegazip; drives out
of the box, of course. SCSI ZIP drives can only be set to
run at SCSI target IDs 5 or 6, but if your SCSI host
adapter's BIOS supports it you can even boot from it. It
is not clear which host adapters support booting from
targets other than 0 or 1, so you will have to consult
your adapter's documentation if you would like to use this
feature.</para>
<para>FreeBSD also supports Parallel Port Zip Drives. Check
that your kernel contains the
<devicename>scbus0</devicename>,
<devicename>da0</devicename>,
<devicename>ppbus0</devicename>, and
<devicename>vp0</devicename> drivers (the GENERIC kernel
contains everything except
<devicename>vp0</devicename>). With all these drivers
present, the Parallel Port drive should be available as
<devicename>/dev/da0s4</devicename>. Disks can be mounted
using <command>mount /dev/da0s4 /mnt</command> OR (for dos
disks) <command>mount_msdos /dev/da0s4 /mnt</command> as
appropriate.</para>
<para>Also check out <link linkend="jaz">the FAQ on
removable drives</link> later in this chapter, and <link
linkend="disklabel">the note on
<quote>formatting</quote></link>in the Administration
chapter.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="jaz-zip-removable-support">
<para>Does FreeBSD support &jaz;, EZ and other removable drives?</para>
</question>
<answer>
<para>Apart from the IDE version of the EZ drive, these are all
SCSI devices, so they should all look like SCSI disks to
FreeBSD, and the IDE EZ should look like an IDE drive.</para>
<para><anchor id="jaz">I am not sure how well FreeBSD supports
changing the media out while running. You will of course need
to dismount the drive before swapping media, and make sure that
any external units are powered on when you boot the system so
FreeBSD can see them.</para>
<para>See <link linkend="disklabel">this note on
<quote>formatting</quote></link>.</para>
</answer>
</qandaentry>
</qandaset>
</sect1>
<sect1 id="compatibility-kbd-mice">
<title>Keyboards and mice</title>
<qandaset>
<qandaentry>
<question id="usbkbd">
<para>Does FreeBSD support my USB keyboard?</para>
</question>
<answer>
<para>FreeBSD 4.X and later supports USB keyboards
out-of-the-box. Enable USB support in
<filename>/etc/rc.conf</filename>.</para>
<para>Once you have USB keyboard support enabled on your
system, the AT keyboard becomes
<devicename>/dev/kbd0</devicename> and the USB keyboard
becomes <devicename>/dev/kbd1</devicename>, if both are
connected to the system. If there is the USB keyboard
only, it will be
<devicename>/dev/ukbd0</devicename>.</para>
<para>If you want to use the USB keyboard in the console,
you have to explicitly tell the console driver to use the
existing USB keyboard. This can be done by running the
following command as a part of system
initialization.</para>
<screen>&prompt.root; <userinput>kbdcontrol -k /dev/kbd1 &lt; /dev/ttyv0 &gt; /dev/null</userinput></screen>
<para>Note that if the USB keyboard is the only keyboard, it
is accessed as <devicename>/dev/kbd0</devicename>, thus,
the command should look like:</para>
<screen>&prompt.root; <userinput>kbdcontrol -k /dev/kbd0 &lt; /dev/ttyv0 &gt; /dev/null</userinput></screen>
<para><filename>/etc/rc.i386</filename> is a good place to
add the above command.</para>
<para>Once this is done, the USB keyboard should work in the
X environment as well without any special settings.</para>
<para>Hot-plugging and unplugging of the USB keyboard may
not work quite right yet. We recommend connecting the
keyboard before starting the system and leaving it
connected until the system is shutdown to avoid
troubles.</para>
<para>See the &man.ukbd.4; manual page for more information.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="busmouse">
<para>I have an unusual bus mouse. How do I set it
up?</para>
</question>
<answer>
<para>FreeBSD supports the bus mouse and the InPort bus
mouse from such manufacturers as Microsoft, Logitech and
ATI. The GENERIC kernel does not include the device
driver. To build a custom kernel with the bus mouse
driver, add the following line to the kernel config
file:</para>
<programlisting>device mse0 at isa? port 0x23c irq5</programlisting>
<para>Bus mice usually come with dedicated interface cards.
These cards may allow you to set the port address and the
IRQ number other than shown above. Refer to the manual of
your mouse and the &man.mse.4; manual page for more
information.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ps2mouse">
<para>How do I use my PS/2 (<quote>mouse port</quote> or
<quote>keyboard</quote>) mouse?</para>
</question>
<answer>
<para>The PS/2 mouse is supported out-of-the-box. The
necessary device driver, <devicename>psm</devicename>, is
included in the kernel.</para>
<para>If your custom kernel does not have this, add the
following line to your kernel configuration and compile a
new kernel.</para>
<programlisting>device psm0 at atkbdc? irq 12</programlisting>
<para>Once the kernel detects <devicename>psm0</devicename>
correctly at boot time, make sure that an entry for
<devicename>psm0</devicename> exists in
<filename>/dev</filename>. You can create this entry by
typing:</para>
<screen>&prompt.root; <userinput>cd /dev; sh MAKEDEV psm0</userinput></screen>
<para>when logged in as <username>root</username>.</para>
<note>
<para>You can omit this step if you are running FreeBSD
5.0-RELEASE or newer with &man.devfs.5; enabled,
since the proper device nodes will be created automatically
under <filename>/dev</filename>.</para>
</note>
</answer>
</qandaentry>
<qandaentry>
<question id="moused">
<para>Is it possible to use a mouse in any way outside the X
Window system?</para>
</question>
<answer>
<para>If you are using the default console driver,
&man.syscons.4;, you can use a mouse pointer in text
consoles to cut &amp; paste text. Run the mouse daemon,
&man.moused.8;, and turn on the mouse pointer in the
virtual console:</para>
<screen>&prompt.root; <userinput>moused -p /dev/<replaceable>xxxx</replaceable> -t <replaceable>yyyy</replaceable></userinput>
&prompt.root; <userinput>vidcontrol -m on</userinput></screen>
<para>Where <replaceable>xxxx</replaceable> is the mouse
device name and <replaceable>yyyy</replaceable> is a
protocol type for the mouse. The mouse daemon can
automatically determine the protocol type of most
mice, except old serial mice. Specify the
<literal>auto</literal> protocol to invoke automatic
detection. If automatic detection does not work, see the
&man.moused.8; manual page for a list of supported
protocol types.</para>
<para>If you have a PS/2 mouse, just add
<literal>moused_enable="YES"</literal> to
<filename>/etc/rc.conf</filename> to start the mouse
daemon at boot-time. Additionally, if you would like to
use the mouse daemon on all virtual terminals instead of
just the console, add <literal>allscreens_flags="-m
on"</literal> to <filename>/etc/rc.conf</filename>.</para>
<para>When the mouse daemon is running, access to the mouse
must be coordinated between the mouse daemon and other
programs such as X Windows. Refer to the FAQ <link
linkend="x-and-moused">Why does my mouse not work with
X?</link> for more details on this issue.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="text-mode-cut-paste">
<para>How do I cut and paste text with a mouse in the text
console?</para>
</question>
<answer>
<para>Once you get the mouse daemon running (see the <link
linkend="moused">previous section</link>), hold down the
button 1 (left button) and move the mouse to select a
region of text. Then, press the button 2 (middle button)
to paste it at the text cursor. Pressing button 3 (right
button) will <quote>extend</quote> the selected region of
text.</para>
<para>If your mouse does not have a middle button, you may
wish to emulate one or remap buttons using mouse daemon
options. See the &man.moused.8; manual page for
details.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="mouse-wheel-buttons">
<para>My mouse has a fancy wheel and buttons. Can I use them in
FreeBSD?</para>
</question>
<answer>
<para>The answer is, unfortunately, <quote>It depends</quote>.
These mice with additional features require specialized driver
in most cases. Unless the mouse device driver or the user
program has specific support for the mouse, it will act just
like a standard two, or three button mouse.</para>
<para>For the possible usage of wheels in the X Window
environment, refer to <link linkend="x-and-wheel">that
section</link>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="laptop-mouse-trackball">
<para>How do I use the mouse/trackball/touchpad on my laptop?</para>
</question>
<answer>
<para>Please refer to <link linkend="ps2mouse">the answer to
the previous question</link>. Also check out the <ulink
url="http://www.FreeBSD.org/docs.html#PAO">Mobile
Computing page</ulink>.</para>
</answer>
</qandaentry>
</qandaset>
</sect1>
<sect1 id="compatibility-networking">
<title>Networking and serial devices</title>
<qandaset>
<qandaentry>
<question id="network-cards">
<para>Which network cards does FreeBSD support?</para>
</question>
<answer>
<para>See the Hardware Notes supplied with each release of
FreeBSD for a more
complete list.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="internal-plugnplay-modem">
<para>Why is FreeBSD not finding my internal Plug &amp; Play
modem?</para>
</question>
<answer>
<para>You will need to add the modem's PnP ID to the PnP ID
list in the serial driver. To enable Plug &amp; Play support,
compile a new kernel with <literal>controller pnp0</literal> in
the configuration file, then reboot the system. The kernel will
print the PnP IDs of all the devices it finds. Copy the PnP ID
from the modem to the table in
<filename>/sys/i386/isa/sio.c</filename>, at about line 2777.
Look for the string <literal>SUP1310</literal> in the structure
<literal>siopnp_ids[]</literal> to find the table. Build the
kernel again, install, reboot, and your modem should be
found.</para>
<para>You may have to manually configure the PnP devices using
the <literal>pnp</literal> command in the boot-time
configuration with a command like</para>
<programlisting>pnp 1 0 enable os irq0 3 drq0 0 port0 0x2f8</programlisting>
<para>to make the modem show.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="support-winmodem">
<para>Does FreeBSD support software modems, such as Winmodems?</para>
</question>
<answer>
<para>FreeBSD supports many software modems via add-on
software. The <filename role="package">comms/ltmdm</filename> port adds
support for modems based on the very popular Lucent LT
chipset. The <filename role="package">comms/mwavem</filename> port
supports the modem in IBM Thinkpad 600 and 700
laptops.</para>
<para>You cannot install FreeBSD via a software modem; this
software must be installed after the OS is
installed.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="support-broadcom">
<para>Is there a native driver for the Broadcom 43xx cards?</para>
</question>
<answer>
<para>No, and there is not likely to be.</para>
<para>Broadcom refuses to publically release programming
information for their wireless chipsets, most likely because
they use software controlled radios. In order to get FCC type
acceptance for their parts, they have to ensure that users
cannot arbitrarily set things like operating frequencies,
modulation parameters and power output. But without knowing
how to program the chipsets, it is nearly impossible to write
a driver.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="multiport-serial-support">
<para>Which multi-port serial cards are supported by
FreeBSD?</para>
</question>
<answer>
<para>There is a list of these in the <ulink
url="&url.books.handbook;/install.html#INSTALL-MISC">Miscellaneous
devices</ulink> section of the handbook.</para>
<para>Some unnamed clone cards have also been known to work,
especially those that claim to be AST compatible.</para>
<para>Check the &man.sio.4; manual page to get more
information on configuring such cards.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="serial-console-prompt">
<para>How do I get the boot: prompt to show on the serial
console?</para>
</question>
<answer>
<orderedlist>
<listitem>
<para>Build a kernel with
<literal>options COMCONSOLE</literal>.</para>
</listitem>
<listitem>
<para>Create /boot.config and place <option>-P</option>
as the only text in the file.</para>
</listitem>
<listitem>
<para>Unplug the keyboard from the system.</para>
</listitem>
</orderedlist>
<para>See
<filename>/usr/src/sys/i386/boot/biosboot/README.serial</filename>
for information.</para>
</answer>
</qandaentry>
</qandaset>
</sect1>
<sect1 id="compatibility-sound">
<title>Sound devices</title>
<qandaset>
<qandaentry>
<question id="sound-card-support">
<para>Which sound cards are supported by FreeBSD?</para>
</question>
<answer>
<para>&os; supports various sound cards including the &soundblaster;,
&soundblaster; Pro, &soundblaster; 16, Pro Audio Spectrum 16,
AdLib, and Gravis UltraSound sound cards (for more details,
see <ulink url="&url.base;/releases/">&os; Release Information</ulink>
and the &man.snd.4; manual page).
There is also limited support for
MPU-401 and compatible MIDI cards. Cards conforming to the
&microsoft; Sound System specification are also supported.</para>
<note>
<para>This is only for sound! This driver does not support
CDROMs, SCSI or joysticks on these cards, except for the
&soundblaster;. The &soundblaster; SCSI interface and some
non-SCSI CDROMs are supported, but you cannot boot off this
device.</para>
</note>
</answer>
</qandaentry>
<qandaentry>
<question id="es1370-silent-pcm">
<para>Workarounds for no sound from es1370 with &man.pcm.4; driver?</para>
</question>
<answer>
<para>You can run the following command every time the machine
booted up:</para>
<screen>&prompt.root; <userinput>mixer pcm 100 vol 100 cd 100</userinput></screen>
</answer>
</qandaentry>
</qandaset>
</sect1>
<sect1 id="compatibility-other">
<title>Other hardware</title>
<qandaset>
<qandaentry>
<question id="other-device-support">
<para>What other devices does FreeBSD support?</para>
</question>
<answer>
<para>See the <ulink
url="&url.books.handbook;/install.html#INSTALL-MISC">Handbook</ulink>
for the list of other devices supported.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="power-management-support">
<para>Does FreeBSD support power management on my laptop?</para>
</question>
<answer>
<para>FreeBSD supports <acronym>APM</acronym> on certain machines.
Please look in the <filename>LINT</filename> kernel config file,
searching for the <acronym>APM</acronym> keyword. Further
information can be found in &man.apm.4;.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="micron-hang-boot">
<para>Why does my Micron system hang at boot time?</para>
</question>
<answer>
<para>Certain Micron motherboards have a non-conforming PCI BIOS
implementation that causes grief when FreeBSD boots because PCI
devices do not get configured at their reported addresses.</para>
<para>Disable the <quote>Plug and Play Operating System</quote>
flag in the BIOS to work around this problem. More information
can be found at <ulink
url="http://cesdis.gsfc.nasa.gov/linux/drivers/vortex.html#micron">
http://cesdis.gsfc.nasa.gov/linux/drivers/vortex.html#micron</ulink></para>
</answer>
</qandaentry>
<qandaentry>
<question id="asusk7v-boot-failure">
<para>The boot floppy hangs on a system with an ASUS K7V
motherboard. How do I fix this?</para>
</question>
<answer>
<para>Go into the BIOS setup and disable the <quote>boot virus
protection</quote>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="micron-3comnic-failure">
<para>Why does my &tm.3com; PCI network card not work with my Micron
computer?</para>
</question>
<answer>
<para>Certain Micron motherboards have a non-conforming PCI BIOS
implementation that does not configure PCI devices at the
addresses reported. This causes grief when FreeBSD
boots.</para>
<para>To work around this problem, disable the
<quote>Plug and Play Operating System</quote> flag in the
BIOS.</para>
<para>More information on this problem is available at URL:
<ulink url="http://cesdis.gsfc.nasa.gov/linux/drivers/vortex.html#micron"></ulink></para>
</answer>
</qandaentry>
</qandaset>
</sect1>
</chapter>
<chapter id="troubleshoot">
<title>Troubleshooting</title>
<qandaset>
<qandaentry>
<question id="awre">
<para>What do I do when I have bad blocks on my hard drive?</para>
</question>
<answer>
<para>With SCSI drives, the drive should be capable of re-mapping
these automatically. However, many drives are shipped with
this feature disabled, for some mysterious reason...</para>
<para>To enable this, you will need to edit the first device page
mode, which can be done on FreeBSD by giving the command
(as <username>root</username>)</para>
<screen>&prompt.root; <userinput>camcontrol modepage sd0 -m 1 -e -P 3</userinput></screen>
<para>and changing the values of AWRE and ARRE from 0 to 1:-</para>
<programlisting>AWRE (Auto Write Reallocation Enbld): 1
ARRE (Auto Read Reallocation Enbld): 1</programlisting>
<para>The following paragraphs were submitted by Ted Mittelstaedt
<email>tedm@toybox.placo.com</email>:</para>
<para>For IDE drives, any bad block is usually a sign of
potential trouble. All modern IDE drives come with internal
bad-block remapping turned on. All IDE hard drive manufacturers
today offer extensive warranties and will replace drives with
bad blocks on them.</para>
<para>If you still want to attempt to rescue an IDE drive with
bad blocks, you can attempt to download the IDE drive
manufacturer's IDE diagnostic program, and run this against the
drive. Sometimes these programs can be set to force the drive
electronics to rescan the drive for bad blocks and lock them
out.</para>
<para>For ESDI, RLL and MFM drives, bad blocks are a normal part
of the drive and are no sign of trouble, generally. With a PC,
the disk drive controller card and BIOS handle the task of
locking out bad sectors. This is fine for operating systems
like DOS that use BIOS code to access the disk. However,
FreeBSD's disk driver does not go through the BIOS, therefore a
mechanism, bad144, exists that replaces this functionality.
bad144 only works with the wd driver (which means it is not
supported in FreeBSD 4.0), it is <emphasis>not</emphasis> able to be used with SCSI.
bad144 works by entering all bad sectors found into a special
file.</para>
<para>One caveat with bad144 - the bad block special file is
placed on the last track of the disk. As this file may possibly
contain a listing for a bad sector that would occur near the
beginning of the disk, where the /kernel file might be located,
it therefore must be accessible to the bootstrap program that
uses BIOS calls to read the kernel file. This means that the
disk with bad144 used on it must not exceed 1024 cylinders, 16
heads, and 63 sectors. This places an effective limit of 500MB
on a disk that is mapped with bad144.</para>
<para>To use bad144, simply set the <quote>Bad Block</quote>
scanning to ON in the FreeBSD fdisk screen during the initial
install. This works up through FreeBSD 2.2.7. The disk must
have less than 1024 cylinders. It is generally recommended that
the disk drive has been in operation for at least 4 hours prior
to this to allow for thermal expansion and track
wandering.</para>
<para>If the disk has more than 1024 cylinders (such as a large
ESDI drive) the ESDI controller uses a special translation mode
to make it work under DOS. The wd driver understands about
these translation modes, IF you enter the
<quote>translated</quote> geometry with the <quote>set
geometry</quote> command in fdisk. You must also NOT use the
<quote>dangerously dedicated</quote> mode of creating the
FreeBSD partition, as this ignores the geometry. Also, even
though fdisk will use your overridden geometry, it still knows
the true size of the disk, and will attempt to create a too
large FreeBSD partition. If the disk geometry is changed to the
translated geometry, the partition MUST be manually created
with the number of blocks.</para>
<para>A quick trick to use is to set up the large ESDI disk
with the ESDI controller, boot it with a DOS disk and
format it with a DOS partition. Then, boot the FreeBSD
install and in the fdisk screen, read off and write down
the blocksize and block numbers for the DOS
partition. Then, reset the geometry to the same that DOS
uses, delete the DOS partition, and create a
<quote>cooperative</quote> FreeBSD partition using the
blocksize you recorded earlier. Then, set the partition
bootable and turn on bad block scanning. During the actual
install, bad144 will run first, before any filesystems are
created (you can view this with an <keycombo
action="simul"><keycap>Alt</keycap><keycap>F2</keycap></keycombo>).
If it has any trouble creating the badsector file, you
have set too large a disk geometry - reboot the system and
start all over again (including repartitioning and
reformatting with DOS).</para>
<para>If remapping is enabled and you are seeing bad blocks,
consider replacing the drive. The bad blocks will only get
worse as time goes on.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="bustek742a-eisa-scsi">
<para>Why does FreeBSD not recognize my Bustek 742a EISA
SCSI controller?</para>
</question>
<answer>
<para>This info is specific to the 742a but may also cover
other Buslogic cards. (Bustek = Buslogic)</para>
<para>There are 2 general <quote>versions</quote> of the 742a
card. They are hardware revisions A-G, and revisions H -
onwards. The revision letter is located after the Assembly
number on the edge of the card. The 742a has 2 ROM chips on it,
one is the BIOS chip and the other is the Firmware chip.
FreeBSD does not care what version of BIOS chip you have but it
does care about what version of firmware chip. Buslogic will
send upgrade ROMs out if you call their tech support dept. The
BIOS and Firmware chips are shipped as a matched pair. You must
have the most current Firmware ROM in your adapter card for
your hardware revision.</para>
<para>The REV A-G cards can only accept BIOS/Firmware sets up to
2.41/2.21. The REV H- up cards can accept the most current
BIOS/Firmware sets of 4.70/3.37. The difference between the
firmware sets is that the 3.37 firmware supports <quote>round
robin</quote>.</para>
<para>The Buslogic cards also have a serial number on them. If
you have an old hardware revision card you can call the Buslogic
RMA department and give them the serial number and attempt to
exchange the card for a newer hardware revision. If the card is
young enough they will do so.</para>
<para>FreeBSD 2.1 only supports Firmware revisions 2.21 onward.
If you have a Firmware revision older than this your card will
not be recognized as a Buslogic card. It may be recognized as
an &adaptec; 1540, however. The early Buslogic firmware contains
an AHA1540 <quote>emulation</quote> mode. This is not a good
thing for an EISA card, however.</para>
<para>If you have an old hardware revision card and you obtain
the 2.21 firmware for it, you will need to check the position
of jumper W1 to B-C, the default is A-B.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="hpnetserver-scsi-failure">
<para>Why does FreeBSD not detect my HP Netserver's SCSI
controller?</para>
</question>
<answer>
<para>This is basically a known problem. The EISA on-board SCSI
controller in the HP Netserver machines occupies EISA slot
number 11, so all the <quote>true</quote> EISA slots are in
front of it. Alas, the address space for EISA slots &gt;= 10
collides with the address space assigned to PCI, and FreeBSD's
auto-configuration currently cannot handle this situation very
well.</para>
<para>So now, the best you can do is to pretend there is no
address range clash :), by bumping the kernel option
<literal>EISA_SLOTS</literal> to a value of 12. Configure and
compile a kernel, as described in the <ulink
url="&url.books.handbook;/kernelconfig.html">Handbook entry on
configuring the kernel</ulink>.</para>
<para>Of course, this does present you with a chicken-and-egg
problem when installing on such a machine. In order to work
around this problem, a special hack is available inside
<emphasis>UserConfig</emphasis>. Do not use the
<quote>visual</quote> interface, but the plain command-line
interface there. Simply type</para>
<programlisting>eisa 12
quit</programlisting>
<para>at the prompt, and install your system as usual. While
it is recommended you compile and install a custom kernel
anyway.</para>
<para>Hopefully, future versions will have a proper fix for
this problem.</para>
<note>
<para>You cannot use a
<literal>dangerously dedicated</literal> disk
with an HP Netserver. See <link linkend="dedicate">this
note</link> for more info.</para>
</note>
</answer>
</qandaentry>
<qandaentry>
<question id="ed1-timeout">
<para>I keep seeing messages like
<errorname>ed1: timeout</errorname>. What do these messages
mean?</para>
</question>
<answer>
<para>This is usually caused by an interrupt conflict (e.g.,
two boards using the same IRQ). FreeBSD prior to 2.0.5R used to
be tolerant of this, and the network driver would still
function in the presence of IRQ conflicts. However, with 2.0.5R
and later, IRQ conflicts are no longer tolerated. Boot with the
-c option and change the ed0/de0/... entry to match your
board.</para>
<para>If you are using the BNC connector on your network card,
you may also see device timeouts because of bad termination. To
check this, attach a terminator directly to the NIC (with no
cable) and see if the error messages go away.</para>
<para>Some NE2000 compatible cards will give this error if there
is no link on the UTP port or if the cable is disconnected.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="bad-3c509">
<para>Why did my &tm.3com; 3C509 card stop working for no
apparent reason?</para>
</question>
<answer>
<para>This card has a bad habit of losing its configuration
information. Refresh your card's settings with the DOS
utility <command>3c5x9.exe</command>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="printer-slow">
<para>My parallel printer is ridiculously slow. What can I do?</para>
</question>
<answer>
<para>If the only problem is that the printer is terribly
slow, try changing your <ulink
url="&url.books.handbook;/printing-intro-setup.html#PRINTING-PARALLEL-PORT-MODE">printer
port mode</ulink> as discussed in the <ulink
url="&url.books.handbook;/printing-intro-setup.html">Printer
Setup</ulink> section of the Handbook.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="signal11">
<para>Why do my programs occasionally die with
<errorname>Signal 11</errorname> errors?</para>
</question>
<answer>
<para>Signal 11 errors are caused when your process has attempted
to access memory which the operating system has not granted it
access to. If something like this is happening at seemingly
random intervals then you need to start investigating things
very carefully.</para>
<para>These problems can usually be attributed to either:</para>
<orderedlist>
<listitem>
<para>If the problem is occurring only in a specific
application that you are developing yourself it is probably
a bug in your code.</para>
</listitem>
<listitem>
<para>If it is a problem with part of the base FreeBSD system,
it may also be buggy code, but more often than not these
problems are found and fixed long before us general FAQ
readers get to use these bits of code (that is what -current
is for).</para>
</listitem>
</orderedlist>
<para>In particular, a dead giveaway that this is
<emphasis>not</emphasis> a FreeBSD bug is if you see the
problem when you are compiling a program, but the activity
that the compiler is carrying out changes each
time.</para>
<para>For example, suppose you are running <quote>make
buildworld</quote>, and the compile fails while trying to
compile <filename>ls.c</filename> into
<filename>ls.o</filename>. If you then run <quote>make
buildworld</quote> again, and the compile fails in the same
place then this is a broken build -- try updating your sources
and try again. If the compile fails elsewhere then this is
almost certainly hardware.</para>
<para>What you should do:</para>
<para>In the first case you can use a debugger e.g. gdb to find
the point in the program which is attempting to access a bogus
address and then fix it.</para>
<para>In the second case you need to verify that it is not your
hardware at fault.</para>
<para>Common causes of this include:</para>
<orderedlist>
<listitem>
<para>Your hard disks might be overheating: Check the fans in
your case are still working, as your disk (and perhaps
other hardware might be overheating).</para>
</listitem>
<listitem>
<para>The processor running is overheating: This might be
because the processor has been overclocked, or the fan on
the processor might have died. In either case you need to
ensure that you have hardware running at what it is
specified to run at, at least while trying to solve this
problem. i.e. Clock it back to the default settings.</para>
<para>If you are overclocking then note that it is far cheaper
to have a slow system than a fried system that needs
replacing! Also the wider community is not often
sympathetic to problems on overclocked systems, whether you
believe it is safe or not.</para>
</listitem>
<listitem>
<para>Dodgy memory: If you have multiple memory SIMMS/DIMMS
installed then pull them all out and try running the
machine with each SIMM or DIMM individually and narrow the
problem down to either the problematic DIMM/SIMM or perhaps
even a combination.</para>
</listitem>
<listitem>
<para>Over-optimistic Motherboard settings: In your BIOS
settings, and some motherboard jumpers you have options to
set various timings, mostly the defaults will be
sufficient, but sometimes, setting the wait states on RAM
too low, or setting the <quote>RAM Speed: Turbo</quote> option, or
similar in the BIOS will cause strange behavior. A
possible idea is to set to BIOS defaults, but it might be
worth noting down your settings first!</para>
</listitem>
<listitem>
<para>Unclean or insufficient power to the motherboard. If you
have any unused I/O boards, hard disks, or CDROMs in your
system, try temporarily removing them or disconnecting the
power cable from them, to see if your power supply can
manage a smaller load. Or try another power supply,
preferably one with a little more power (for instance, if
your current power supply is rated at 250 Watts try one
rated at 300 Watts).</para>
</listitem>
</orderedlist>
<para>You should also read the SIG11 FAQ (listed below) which has
excellent explanations of all these problems, albeit from a
&linux; viewpoint. It also discusses how memory testing software
or hardware can still pass faulty memory.</para>
<para>Finally, if none of this has helped it is possible that
you have just found a bug in FreeBSD, and you should follow the
instructions to send a problem report.</para>
<para>There is an extensive FAQ on this at <ulink
url="http://www.bitwizard.nl/sig11/">
the SIG11 problem FAQ</ulink></para>
</answer>
</qandaentry>
<qandaentry>
<question id="trap-12-panic">
<para>My system crashes with either <errorname>Fatal
trap 12: page fault in kernel mode</errorname>, or
<errorname>panic:</errorname>, and spits out a
bunch of information. What should I do?</para>
</question>
<answer>
<para>The FreeBSD developers are very interested in these
errors, but need some more information than just the
error you see. Copy your full crash message. Then
consult the FAQ section on <link linkend=
"KERNEL-PANIC-TROUBLESHOOTING">kernel panics</link>,
build a debugging kernel, and get a backtrace. This
might sound difficult, but you do not need any
programming skills; you just have to follow the
instructions.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="screen-loses-sync">
<para>Why does the screen go black and lose sync when I
boot?</para>
</question>
<answer>
<para>This is a known problem with the ATI Mach 64 video card.
The problem is that this card uses address
<literal>2e8</literal>, and the fourth serial port does too.
Due to a bug (feature?) in the &man.sio.4;
driver it will touch this port even if you do not have the
fourth serial port, and <emphasis>even</emphasis> if
you disable sio3 (the fourth port) which normally uses this
address.</para>
<para>Until the bug has been fixed, you can use this
workaround:</para>
<orderedlist>
<listitem>
<para>Enter <option>-c</option> at the boot prompt.
(This will put the kernel into configuration mode).</para>
</listitem>
<listitem>
<para>Disable <devicename>sio0</devicename>,
<devicename>sio1</devicename>,
<devicename>sio2</devicename> and
<devicename>sio3</devicename> (all of them). This way
the sio driver does not get activated -&gt; no
problems.</para>
</listitem>
<listitem>
<para>Type exit to continue booting.</para>
</listitem>
</orderedlist>
<para>If you want to be able to use your serial ports, you will
have to build a new kernel with the following modification: in
<filename>/usr/src/sys/i386/isa/sio.c</filename> find the one
occurrence of the string <literal>0x2e8</literal> and remove
that string and the preceding comma (keep the trailing comma).
Now follow the normal procedure of building a new
kernel.</para>
<para>Even after applying these workarounds, you may still find
that the X Window System does not work properly. If this is the
case, make sure that the &xfree86; version you are using is at
least &xfree86; 3.3.3 or higher. This version and upwards has
built-in support for the Mach64 cards and even a dedicated X
server for those cards.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="reallybigram">
<para>Why does FreeBSD only use 64 MB of RAM when my system has
128 MB of RAM installed?</para>
</question>
<answer>
<para>Due to the manner in which FreeBSD gets the memory size
from the BIOS, it can only detect 16 bits worth of Kbytes in
size (65535 Kbytes = 64MB) (or less... some BIOSes peg the
memory size to 16M). If you have more than 64MB, FreeBSD will
attempt to detect it; however, the attempt may fail.</para>
<para>To work around this problem, you need to use the kernel
option specified below. There is a way to get complete memory
information from the BIOS, but we do not have room in the
bootblocks to do it. Someday when lack of room in the
bootblocks is fixed, we will use the extended BIOS functions to
get the full memory information...but for now we are stuck with
the kernel option.</para>
<para><literal>options "MAXMEM=<replaceable>n</replaceable>"</literal></para>
<para>Where <replaceable>n</replaceable> is your memory in
Kilobytes. For a 128 MB machine, you would want to use
<literal>131072</literal>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="kmem-map-too-small">
<para>My system has more than 1 GB of RAM, and I'm getting panics
with <quote>kmem_map too small</quote> messages. What is wrong?
</para>
</question>
<answer>
<para>Normally, FreeBSD determines a number of kernel parameters,
such as as the maximum number of files that can be open
concurrently, from the amount of memory installed in the
system. On systems with one gigabyte of RAM or more, this
<quote>auto sizing</quote> mechanism may choose values that are
too high: while starting up, the kernel allocates various tables
and other structures that fill up most of the available kernel
memory. Later on, while the system is running, the kernel has no
more space left for dynamic memory allocations, and
panics.</para>
<para>Compile your own kernel, and add the
<option>VM_KMEM_SIZE_MAX</option> to your kernel configuration
file, increasing the maximum size to 400&nbsp;MB
(<option>options VM_KMEM_SIZE_MAX=419430400</option>).
400&nbsp;MB appears to be sufficient for machines with up to
6&nbsp;GB of memory.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="panic-kmemmap-too-small">
<para>My system does not have 1 GB of RAM, and FreeBSD still
panics with <errorname>kmem_map too small!</errorname>
</para>
</question>
<answer>
<para>The panic indicates that the system ran out of virtual
memory for network buffers (specifically, mbuf clusters). You
can increase the amount of VM available for mbuf clusters by
adding:</para>
<para><literal>options NMBCLUSTERS=<replaceable>n</replaceable></literal></para>
<para>to your kernel config file, where
<replaceable>n</replaceable> is a number in the range
512-4096, depending on the number of concurrent TCP
connections you need to support. We recommend trying
2048 - this should get rid of the panic completely. You
can monitor the number of mbuf clusters allocated/in use
on the system with <command>netstat -m</command> (see
&man.netstat.1;). The default value for NMBCLUSTERS is
<literal>1024 + MAXUSERS * 64</literal>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="proc-table-full">
<para>Why do I get the error <errorname>/kernel: proc: table
is full</errorname>?</para>
</question>
<answer>
<para>The FreeBSD kernel will only allow a certain number of
processes to exist at one time. The number is based on
the <literal>MAXUSERS</literal> option in the kernel
configuration. <literal>MAXUSERS</literal> also affects
various other in-kernel limits, such as network buffers
(see <link linkend="panic-kmemmap-too-small">this</link>
earlier question). If your machine is heavily loaded, you
probably want to increase <literal>MAXUSERS</literal>.
This will increase these other system limits in addition
to the maximum number of processes.</para>
<para>After FreeBSD 4.4, <literal>MAXUSERS</literal> became
a tunable value that could be set with
<varname>kern.maxusers</varname> in
<filename>/boot/loader.conf</filename>. In earlier
versions of FreeBSD, you need to adjust
<literal>MAXUSERS</literal> in your kernel
configuration.</para>
<para>If your machine is lightly loaded, and you are simply
running a very large number of processes, you can adjust
this with the <varname>kern.maxproc</varname> sysctl. If
these processes are being run by a single user, you will
also need to adjust <varname>kern.maxprocperuid</varname>
to be one less than your new
<varname>kern.maxproc</varname> value. (It must be at
least one less because one system program, &man.init.8;,
must always be running.)</para>
<para>To make a sysctl permanent across reboots, set this in
<filename>/etc/sysctl.conf</filename> in recent versions
of FreeBSD, or <filename>/etc/rc.local</filename> in older
versions.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="cmap-busy-panic">
<para>Why do I get an error reading <errorname>CMAP
busy</errorname> when rebooting with a new
kernel?</para>
</question>
<answer>
<para>The logic that attempts to detect an out of date
<filename>/var/db/kvm_*.db</filename> files sometimes fails
and using a mismatched file can sometimes lead to panics.</para>
<para>If this happens, reboot single-user and do:</para>
<screen>&prompt.root; <userinput>rm /var/db/kvm_*.db</userinput></screen>
</answer>
</qandaentry>
<qandaentry>
<question id="brkadrint-illegal-host-access">
<para>What does the message <errorname>ahc0: brkadrint,
Illegal Host Access at seqaddr 0x0</errorname>
mean?</para>
</question>
<answer>
<para>This is a conflict with an Ultrastor SCSI Host Adapter.</para>
<para>During the boot process enter the kernel configuration
menu and disable
<devicename>uha0</devicename>,
which is causing the problem.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="aci0-illegal-cable">
<para>When I boot my system, I get the error
<errorname>ahc0: illegal cable configuration</errorname>.
My cabling is correct. What is going on?</para>
</question>
<answer>
<para>Your motherboard lacks the external logic to support
automatic termination. Switch your SCSI BIOS to specify
the correct termination for your configuration rather
than automatic termination. The AIC7XXX driver cannot
determine if the external logic for cable detection (and
thus auto-termination) is available. The driver simply
assumes that this support must exist if the configuration
contained in the serial EEPROM is set to "automatic
termination". Without the external cable detection logic
the driver will often configure termination incorrectly,
which can compromise the reliability of the SCSI
bus.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="mail-loopback">
<para>Why does Sendmail give me an error reading
<quote><errorname>mail loops back to
myself</errorname></quote>?</para>
</question>
<answer>
<para>This is answered in the sendmail FAQ as follows:-</para>
<literallayout> * I'm getting "Local configuration error" messages, such as:
553 relay.domain.net config error: mail loops back to myself
554 &lt;user@domain.net&gt;... Local configuration error
How can I solve this problem?
You have asked mail to the domain (e.g., domain.net) to be
forwarded to a specific host (in this case, relay.domain.net)
by using an MX record, but the relay machine does not recognize
itself as domain.net. Add domain.net to /etc/mail/local-host-names
(if you are using FEATURE(use_cw_file)) or add "Cw domain.net"
to /etc/mail/sendmail.cf.
</literallayout>
<para>The current version of the <ulink
url="ftp://rtfm.mit.edu/pub/usenet/news.answers/mail/sendmail-faq">sendmail
FAQ</ulink> is no longer maintained with the sendmail release.
It is however regularly posted to <ulink
url="news:comp.mail.sendmail">comp.mail.sendmail</ulink>,
<ulink url="news:comp.mail.misc">comp.mail.misc</ulink>, <ulink
url="news:comp.mail.smail">comp.mail.smail</ulink>, <ulink
url="news:comp.answers">comp.answers</ulink>, and <ulink
url="news:news.answers">news.answers</ulink>. You can also
receive a copy via email by sending a message to
<email>mail-server@rtfm.mit.edu</email> with the command
<literal>send usenet/news.answers/mail/sendmail-faq</literal>
as the body of the message.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="remote-fullscreen">
<para>Why do full screen applications on remote machines
misbehave?</para>
</question>
<answer>
<para>The remote machine may be setting your terminal type
to something other than the <literal>cons25</literal> terminal
type required by the FreeBSD console.</para>
<para>There are a number of possible work-arounds for this
problem:</para>
<itemizedlist>
<listitem>
<para>After logging on to the remote machine, set your
TERM shell variable to <literal>ansi</literal> or
<literal>sco</literal> if the remote machine knows
about these terminal types.</para>
</listitem>
<listitem>
<para>Use a VT100 emulator like
<application>screen</application> at the FreeBSD console.
<application>screen</application> offers you the ability
to run multiple concurrent sessions from one terminal,
and is a neat program in its own right. Each
<application>screen</application> window behaves like a
VT100 terminal, so the TERM variable at the remote end
should be set to <literal>vt100</literal>.</para>
</listitem>
<listitem>
<para>Install the <literal>cons25</literal> terminal
database entry on the remote machine. The way to do this
depends on the operating system on the remote machine.
The system administration manuals for the remote system
should be able to help you here.</para>
</listitem>
<listitem>
<para>Fire up an X server at the FreeBSD end and login to
the remote machine using an X based terminal emulator
such as <command>xterm</command> or
<command>rxvt</command>. The TERM variable at the remote
host should be set to <literal>xterm</literal> or
<literal>vt100</literal>.</para>
</listitem>
</itemizedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="calcru-negative">
<para>Why does my machine print
<errorname>calcru: negative time...</errorname>?</para>
</question>
<answer>
<para>This can be caused by various hardware or software
ailments relating to interrupts. It may be due to bugs but can
also happen by nature of certain devices. Running TCP/IP over
the parallel port using a large MTU is one good way to provoke
this problem. Graphics accelerators can also get you here, in
which case you should check the interrupt setting of the card
first.</para>
<para>A side effect of this problem are dying processes with the
message <quote>SIGXCPU exceeded cpu time limit</quote>.</para>
<para>If the problem cannot be fixed otherwise the solution
is to set this sysctl variable:</para>
<screen>&prompt.root; <userinput>sysctl -w kern.timecounter.method=1</userinput></screen>
<note>
<para>The <option>-w</option> option of &man.sysctl.8; is
deprecated and silently ignored in &os; 4.4-RELEASE and all
newer versions. You can safely ommit it when setting options
with <command>sysctl</command> as shown above.</para>
</note>
<para>This means a performance impact, but considering the cause
of this problem, you probably will not notice. If the problem
persists, keep the sysctl set to one and set the
<literal>NTIMECOUNTER</literal> option in your kernel to
increasingly large values. If by the time you have reached
<literal>NTIMECOUNTER=20</literal> the problem is not solved,
interrupts are too hosed on your machine for reliable
time keeping.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="pcm0-not-found">
<para>I see <errorname>pcm0 not found</errorname> or my
sound card is found as <devicename>pcm1</devicename> but I
have <literal>device pcm0</literal> in my kernel config
file. What is going on?</para>
</question>
<answer>
<para>This occurs in &os; 3.X with PCI sound cards. The
<devicename>pcm0</devicename> device is reserved
exclusively for ISA-based cards so, if you have a PCI
card, then you will see this error, and your card will
appear as <devicename>pcm1</devicename>.
<note>
<para>You cannot remove the warning by simply changing
the line in the kernel config file to <literal>device
pcm1</literal> as this will result in
<devicename>pcm1</devicename> being reserved for ISA
cards and your PCI card being found as
<devicename>pcm2</devicename> (along with the warning
<errorname>pcm1 not found</errorname>).</para>
</note>
<para>If you have a PCI sound card, you will also have to make the
<devicename>snd1</devicename> device rather than
<devicename>snd0</devicename>:</para>
<screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>./MAKEDEV snd1</userinput></screen>
<para>This situation does not arise in &os; 4.X as a lot
of work has been done to make it more
<emphasis>PnP-centric</emphasis> and the
<devicename>pcm0</devicename> device is no longer reserved
exclusively for ISA cards</para>
</answer>
</qandaentry>
<qandaentry>
<question id="pnp-not-found">
<para>Why is my PnP card no longer found (or found as
<literal>unknown</literal>) since upgrading to FreeBSD 4.X?</para>
</question>
<answer>
<para>FreeBSD 4.X is now much more <emphasis>PnP-centric</emphasis>
and this has had the side effect of some PnP devices (e.g. sound
cards and internal modems) not working even though they worked
under FreeBSD 3.X.</para>
<para>The reasons for this behavior are explained by the following
e-mail, posted to the freebsd-questions mailing list by Peter
Wemm, in answer to a question about an internal modem that was
no longer found after an upgrade to FreeBSD 4.X (the comments
in <literal>[]</literal> have been added to clarify the
context.</para>
<note>
<para>The contents of this quotation has been updated from
its original text.</para>
</note>
<blockquote>
<para>The PNP bios preconfigured it [the modem] and left it
laying around in port space, so [in 3.X] the old-style ISA
probes <quote>found</quote> it there.</para>
<para>Under 4.0, the ISA code is much more PnP-centric. It was
possible [in 3.X] for an ISA probe to find a
<quote>stray</quote> device and then for the PNP device id to
match and then fail due to resource conflicts. So, it
disables the programmable cards first so this double probing
cannot happen. It also means that it needs to know the PnP
ids for supported PnP hardware. Making this more user
tweakable is on the TODO list.</para>
</blockquote>
<para>To get the device working again requires finding its PnP id
and adding it to the list that the ISA probes use to identify
PnP devices. This is obtained using &man.pnpinfo.8; to probe the
device, for example this is the output from &man.pnpinfo.8; for
an internal modem:</para>
<screen>&prompt.root; <userinput>pnpinfo</userinput>
Checking for Plug-n-Play devices...
Card assigned CSN #1
Vendor ID PMC2430 (0x3024a341), Serial Number 0xffffffff
PnP Version 1.0, Vendor Version 0
Device Description: Pace 56 Voice Internal Plug & Play Modem
Logical Device ID: PMC2430 0x3024a341 #0
Device supports I/O Range Check
TAG Start DF
I/O Range 0x3f8 .. 0x3f8, alignment 0x8, len 0x8
[16-bit addr]
IRQ: 4 - only one type (true/edge)</screen>
<para>[more TAG lines elided]</para>
<screen>TAG End DF
End Tag
Successfully got 31 resources, 1 logical fdevs
-- card select # 0x0001
CSN PMC2430 (0x3024a341), Serial Number 0xffffffff
Logical device #0
IO: 0x03e8 0x03e8 0x03e8 0x03e8 0x03e8 0x03e8 0x03e8 0x03e8
IRQ 5 0
DMA 4 0
IO range check 0x00 activate 0x01</screen>
<para>The information you require is in the
<quote>Vendor ID</quote> line at the start of the output. The
hexadecimal number in parentheses (0x3024a341 in this example)
is the PnP id and the string immediately before this (PMC2430)
is a unique ASCII id.</para>
<para>Alternatively, if &man.pnpinfo.8; does not list the card in
question, &man.pciconf.8; can be used instead. This is part of
the output from <command>pciconf -vl</command> for an onboard
sound chip:</para>
<screen>&prompt.root; <userinput>pciconf -vl</userinput>
chip1@pci0:31:5: class=0x040100 card=0x00931028 chip=0x24158086 rev=0x02 hdr=0x00
vendor = 'Intel Corporation'
device = '82801AA 8xx Chipset AC'97 Audio Controller'
class = multimedia
subclass = audio</screen>
<para>Here, you would use the <varname>chip</varname> value,
<quote>0x24158086</quote>.</para>
<para>This information (Vendor ID or chip value) needs adding
to the file
<filename>/usr/src/sys/isa/sio.c</filename>.</para>
<para>You should first make a backup of <filename>sio.c</filename>
just in case things go wrong. You will also need it to make the
patch to submit with your PR (you are going to submit a PR,
are you not?) then edit <filename>sio.c</filename> and search
for the line</para>
<programlisting>static struct isa_pnp_id sio_ids[] = {</programlisting>
<para>then scroll down to find the correct place to add the entry
for your device. The entries look like this, and are sorted on
the ASCII Vendor ID string which should be included in the
comment to the right of the line of code along with all (if it
will fit) or part of the <emphasis>Device Description</emphasis>
from the output of &man.pnpinfo.8;:</para>
<programlisting>{0x0f804f3f, NULL}, /* OZO800f - Zoom 2812 (56k Modem) */
{0x39804f3f, NULL}, /* OZO8039 - Zoom 56k flex */
{0x3024a341, NULL}, /* PMC2430 - Pace 56 Voice Internal Modem */
{0x1000eb49, NULL}, /* ROK0010 - Rockwell ? */
{0x5002734a, NULL}, /* RSS0250 - 5614Jx3(G) Internal Modem */</programlisting>
<para>Add the hexadecimal Vendor ID for your device in the
correct place, save the file, rebuild your kernel, and reboot.
Your device should now be found as an <literal>sio</literal>
device as it was under FreeBSD 3.X</para>
</answer>
</qandaentry>
<qandaentry>
<question id="nlist-failed">
<para>Why do I get the error <errorname>nlist failed</errorname> when
running, for example, <command>top</command> or
<command>systat</command>?</para>
</question>
<answer>
<para>The problem is that the application you are trying to run is
looking for a specific kernel symbol, but, for whatever reason,
cannot find it; this error stems from one of two problems:</para>
<itemizedlist>
<listitem>
<para>Your kernel and userland are not synchronized (i.e., you
built a new kernel but did not do an
<maketarget>installworld</maketarget>, or vice versa), and
thus the symbol table is different from what the user
application thinks it is. If this is the case, simply
complete the upgrade process (see
<filename>/usr/src/UPDATING</filename> for the correct
sequence).</para>
</listitem>
<listitem>
<para>You are not using <command>/boot/loader</command> to load
your kernel, but doing it directly from boot2 (see
&man.boot.8;). While there is nothing wrong with bypassing
<command>/boot/loader</command>, it generally does a better
job of making the kernel symbols available to user
applications.</para>
</listitem>
</itemizedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="connection-delay">
<para>Why does it take so long to connect to my computer via
<command>ssh</command> or <command>telnet</command>?</para>
</question>
<answer>
<para>The symptom: there is a long delay between the time the TCP
connection is established and the time when the client software
asks for a password (or, in &man.telnet.1;'s case, when a login
prompt appears).</para>
<para>The problem: more likely than not, the delay is caused by
the server software trying to resolve the client's IP address
into a hostname. Many servers, including the Telnet and SSH
servers that come with FreeBSD, do this in order to, among
other things, store the hostname in a log file for future
reference by the administrator.</para>
<para>The remedy: if the problem occurs whenever you connect from
your computer (the client) to any server, the problem is with
the client; likewise, if the problem only occurs when someone
connects to your computer (the server) the problem is with the
server.</para>
<para>If the problem is with the client, the only remedy is to
fix the DNS so the server can resolve it. If this is on a
local network, consider it a server problem and keep reading;
conversely, if this is on the global Internet, you will most
likely need to contact your ISP and ask them to fix it for
you.</para>
<para>If the problem is with the server, and this is on a local
network, you need to configure the server to be able to resolve
address-to-hostname queries for your local address range. See
the &man.hosts.5; and &man.named.8; manual pages for more
information. If this is on the global Internet, the problem
may be that your server's resolver is not functioning
correctly. To check, try to look up another host--say,
<hostid>www.yahoo.com</hostid>. If it does not work, that is
your problem.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="stray-irq">
<para>What does <errorname>stray IRQ</errorname> mean?</para>
</question>
<answer>
<para>Stray IRQs are indications of hardware IRQ glitches,
mostly from hardware that removes its interrupt request in
the middle of the interrupt request acknowledge
cycle.</para>
<para>One has three options for dealing with this:</para>
<itemizedlist>
<listitem>
<para>Live with the warnings. All except the first 5
per irq are suppressed anyway.</para>
</listitem>
<listitem>
<para>Break the warnings by changing 5 to 0 in
<function>isa_strayintr()</function> so that all the
warnings are suppressed.</para>
</listitem>
<listitem>
<para>Break the warnings by installing parallel port
hardware that uses irq 7 and the PPP driver for it (this
happens on most systems), and install an ide drive or
other hardware that uses irq 15 and a suitable driver
for it.</para>
</listitem>
</itemizedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="file-table-full">
<para>Why does <errorname>file: table is full</errorname> show up
repeatedly in dmesg?</para>
</question>
<answer>
<para>
This error message indicates you have exhausted the number
of available file descriptors on your system. Please see
the <ulink
url="&url.books.handbook;/configtuning-kernel-limits.html#KERN-MAXFILES">kern.maxfiles
</ulink>section of the <ulink
url="&url.books.handbook;/configtuning-kernel-limits.html">Tuning
Kernel Limits</ulink> section of the Handbook for a
discussion and solution.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="laptop-clock-skew">
<para>Why does the clock on my laptop keep incorrect time?</para>
</question>
<answer>
<para>Your laptop has two or more clocks, and FreeBSD has chosen to
use the wrong one.</para>
<para>Run &man.dmesg.8;, and check for lines that contain
<literal>Timecounter</literal>. The last line printed is the one
that FreeBSD chose, and will almost certainly be
<literal>TSC</literal>.</para>
<screen>&prompt.root; <userinput>dmesg | grep Timecounter</userinput>
Timecounter "i8254" frequency 1193182 Hz
Timecounter "TSC" frequency 595573479 Hz</screen>
<para>You can confirm this by checking the
<varname>kern.timecounter.hardware</varname>
&man.sysctl.3;.</para>
<screen>&prompt.root; <userinput>sysctl kern.timecounter.hardware</userinput>
kern.timecounter.hardware: TSC</screen>
<para>The BIOS may modify the TSC clock&mdash;perhaps to change the
speed of the processor when running from batteries, or going into
a power saving mode, but FreeBSD is unaware of these adjustments,
and appears to gain or lose time.</para>
<para>In this example, the <literal>i8254</literal> clock is also
available, and can be selected by writing its name to the
<varname>kern.timecounter.hardware</varname>
&man.sysctl.3;.</para>
<screen>&prompt.root; <userinput>sysctl -w kern.timecounter.hardware=i8254</userinput>
kern.timecounter.hardware: TSC -&gt; i8254</screen>
<para>Your laptop should now start keeping more accurate
time.</para>
<para>To have this change automatically run at boot time, add the
following line to <filename>/etc/sysctl.conf</filename>.</para>
<programlisting>kern.timecounter.hardware=i8254</programlisting>
</answer>
</qandaentry>
<qandaentry>
<question id="null-null">
<para>Why did my laptop fail to correctly probe PC cards?</para>
</question>
<answer>
<para>This problem is common on laptops that boot more than
one operating system. Some non-BSD operating systems
leave PC card hardware in an inconsistent state.
<command>pccardd</command> will detect the card as
<errorname>"(null)""(null)"</errorname> instead of its
actual model.</para>
<para>You must remove all power from the PC card slot to
fully reset the hardware. Completely power off the
laptop. (Do not suspend it, do not let it go into standby;
the power needs to be completely off.) Wait a few
moments, and reboot. Your PC card should work now.</para>
<para>Some laptop hardware lies when it claims to be off.
If the above does not work shut down, remove the battery,
wait a moment, replace the battery, and reboot.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="boot-read-error">
<para>Why does FreeBSD's boot loader display
<errorname>Read error</errorname> and stop after the BIOS
screen?</para>
</question>
<answer>
<para>FreeBSD's boot loader is incorrectly recognizing the hard
drive's geometry. This must be manually set within fdisk when
creating or modifying FreeBSD's slice.
</para>
<para>The correct drive geometry values can be found within the
machine's BIOS. Look for the number of cylinders, heads and
sectors for the particular drive.
</para>
<para>Within &man.sysinstall.8;'s fdisk, hit
<keycap>G</keycap> to set the drive geometry.</para>
<para>A dialog will pop up requesting the number of
cylinders, heads and sectors. Type the numbers found from
the BIOS separated by forward slashes. For example, values
of 5000 cylinders, 250 heads, and 60 sectors would be entered as
<userinput>5000/250/60</userinput>.
</para>
<para>Press enter to set the values, and hit
<keycap>W</keycap> to write the new partition table to the
drive.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="bootmanager-restore">
<para>Another operating system destroyed my Boot Manager. How do I
get it back?</para>
</question>
<answer>
<para>Enter &man.sysinstall.8; and choose Configure,
then Fdisk. Select the disk the Boot Manager resided on
with the <keycap>space</keycap> key. Press
<keycap>W</keycap> to write changes to the drive. A prompt
will appear asking which boot loader to install. Select this,
and it will be restored.
</para>
</answer>
</qandaentry>
<qandaentry>
<question id="indefinite-wait-buffer">
<para>What does the error <errorname>swap_pager: indefinite
wait buffer:</errorname> mean?</para>
</question>
<answer>
<para>This means that a process is trying to page memory to
disk, and the page attempt has hung trying to access the
disk for more than 20 seconds. It might be caused by bad
blocks on the disk drive, disk wiring, cables, or any
other disk I/O-related hardware. If the drive itself is
actually bad, you will also see disk errors in
<filename>/var/log/messages</filename> and in the output
of <command>dmesg</command>. Otherwise, check your cables
and connections.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="udma-icrc">
<para>What are <quote>UDMA ICRC</quote> errors, and how do I
fix them?</para>
</question>
<answer>
<para>The &man.ata.4; driver reports <quote>UDMA ICRC</quote>
errors when a DMA transfer to or from a drive is corrupted.
The driver will retry the operation a few times. Should
the retries fail, it will switch from DMA to the slower PIO
mode of communication with the device.</para>
<para>The problem can be caused by many factors, although
perhaps the most common cause is faulty or incorrect
cabling. Check that the ATA cables are undamaged and rated
for the Ultra DMA mode in use. If you are using removable
drive trays, they must also be compatible. Be sure that
all connections are making good contact. Problems have
also been noticed when an old drive is installed on the
same ATA channel as an Ultra DMA 66 (or faster) drive.
Lastly, these errors can indicate that the drive is
failing. Most drive vendors provide testing software for
their drives, so test your drive, and, if necessary, back
up your data and replace it.</para>
<para>The &man.atacontrol.8; utility can be used to show and
select the DMA or PIO modes used for each ATA device. In
particular, <command>atacontrol mode
<replaceable>channel</replaceable></command> will show the
modes in use on a particular ATA channel, where the primary
channel is numbered 0, and so on.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="lock-order-reversal">
<para>What is a <errorname>lock order reversal</errorname>?</para>
</question>
<answer>
<para>&a.rwatson; answered this question very succinctly on
the freebsd-current list in a thread entitled <quote><ulink
url="http://docs.freebsd.org/cgi/getmsg.cgi?fetch=65165+0+/usr/local/www/db/text/2003/freebsd-current/20031221.freebsd-current">lock
order reversals - what do they mean?</ulink></quote></para>
<blockquote>
<attribution>&a.rwatson; on freebsd-current, December 14,
2003</attribution>
<para>These warnings are generated by Witness, a run-time lock
diagnostic system found in FreeBSD -CURRENT kernels (but
removed in releases). You can read more about Witness in the
&man.witness.4; man page, which talks about its capabilities. Among
other things, Witness performs run-time lock order verification
using a combination of hard coded lock orders, and run-time
detected lock orders, and generates console warnings when lock
orders are violated. The intent of this is to detect the
potential for deadlocks due to lock order violations; it is worth
observing that Witness is actually slightly conservative, and so
it is possible to get false positives. In the event that Witness
is accurately reporting a lock order problem, it is basically
saying "If you were unlucky, a deadlock would have happened
here". There are a couple of "well known" false positives,
which we need to do a better job of documenting to prevent
spurious reports. The non-well-known ones typically correspond
to bugs in newly added locking, as lock order reversals usually
get fixed pretty quickly because Witness is busy generating
warnings :-).</para>
</blockquote>
<note>
<para>See <ulink
url="http://sources.zabbadoz.net/freebsd/lor.html">Bjoern
Zeeb's lock order reversal page</ulink> for the status of
known lock order reversals.</para>
</note>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter id="commercial">
<title>Commercial Applications</title>
<note>
<para>This section is still very sparse, though we are hoping, of
course, that companies will add to it! :) The FreeBSD group has
no financial interest in any of the companies listed here but
simply lists them as a public service (and feels that commercial
interest in FreeBSD can have very positive effects on FreeBSD's
long-term viability). We encourage commercial software vendors to
send their entries here for inclusion. See <ulink
url="&url.base;/commercial/index.html">the
Vendors page</ulink> for a longer list.</para>
</note>
<qandaset>
<qandaentry>
<question id="officesuite">
<para>Where can I get an Office Suite for FreeBSD?</para>
</question>
<answer>
<itemizedlist>
<listitem>
<para><ulink url="http://www.freebsdmall.com/">The
FreeBSD Mall</ulink> offers a FreeBSD native version
of <ulink
url="http://www.vistasource.com/">VistaSource</ulink>
ApplixWare 5.</para>
<para>ApplixWare is a rich full-featured, commercial
Office Suite for FreeBSD containing a word processor,
spreadsheet, presentation program, vector drawing
package, and other applications.
</para>
<para>ApplixWare is offered as part of the FreeBSD Mall's BSD
Desktop Edition.</para>
</listitem>
<listitem>
<para>The &linux; version of <ulink
url="http://www.sun.com/staroffice/">StarOffice</ulink>
works flawlessly on FreeBSD. The easiest way to
install the &linux; version of StarOffice is through the
<ulink url="&url.books.handbook;/ports.html">FreeBSD Ports
collection</ulink>. The
open-source <ulink
url="http://www.openoffice.org/">OpenOffice</ulink>
suite also works, and is also in the Ports Collection.</para>
</listitem>
</itemizedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="motif">
<para>Where can I get &motif; for FreeBSD?</para>
</question>
<answer>
<para>The Open Group has released the source code to &motif; 2.2.2.
You can install the <literal>open-motif</literal> package, or
compile it from ports. Refer to
<ulink url="&url.books.handbook;/ports.html">the ports section of the
Handbook</ulink> for more information on how to do this.
<note>
<para>The Open &motif; distribution only allows redistribution
if it is running on an <ulink url="http://www.opensource.org/">
open source</ulink> operating system.</para>
</note>
</para>
<para>In addition, there are commercial distributions of the &motif;
software available. These, however, are not for free, but their
license allows them to be used in closed-source software.
Contact <link linkend="apps2go">Apps2go</link> for the
least expensive ELF &motif; 2.1.20 distribution for FreeBSD
(either &i386; or Alpha).<anchor id="apps2go"></para>
<para>There are two distributions, the <quote>development
edition</quote> and the <quote>runtime edition</quote> (for
much less). These distributions includes:</para>
<itemizedlist>
<listitem>
<para>OSF/&motif; manager, xmbind, panner, wsm.</para>
</listitem>
<listitem>
<para>Development kit with uil, mrm, xm, xmcxx, include
and Imake files.</para>
</listitem>
<listitem>
<para>Static and dynamic ELF libraries.</para>
</listitem>
<listitem>
<para>Demonstration applets.</para>
</listitem>
</itemizedlist>
<para>Be sure to specify that you want the FreeBSD version of
&motif; when ordering (do not forget to mention the architecture
you want too)! Versions for NetBSD and OpenBSD are also sold by
<emphasis>Apps2go</emphasis>. This is currently a FTP only
download.</para>
<variablelist>
<varlistentry>
<term>More info</term>
<listitem>
<para><ulink url="http://www.apps2go.com/">
Apps2go WWW page</ulink></para>
</listitem>
</varlistentry>
<varlistentry>
<term>or</term>
<listitem>
<para>
<email>sales@apps2go.com</email> or
<email>support@apps2go.com</email>
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>or</term>
<listitem>
<para>phone (817) 431 8775 or +1 817 431-8775</para>
</listitem>
</varlistentry>
</variablelist>
<para>Contact <link linkend="metrox">Metro Link</link>
for an either ELF or a.out &motif; 2.1 distribution for
FreeBSD.</para>
<para>This distribution includes:</para>
<itemizedlist>
<listitem>
<para>OSF/&motif; manager, xmbind, panner, wsm.</para>
</listitem>
<listitem>
<para>Development kit with uil, mrm, xm, xmcxx, include
and Imake files.</para>
</listitem>
<listitem>
<para>Static and dynamic libraries (specify ELF for use
with FreeBSD 3.0 and later; or a.out for use with FreeBSD
2.2.8 and earlier).</para>
</listitem>
<listitem>
<para>Demonstration applets.</para>
</listitem>
<listitem>
<para>Preformatted manual pages.</para>
</listitem>
</itemizedlist>
<para>Be sure to specify that you want the FreeBSD version
of &motif; when ordering! Versions for &linux; are also sold by
<emphasis>Metro Link</emphasis>. This is available on either a
CDROM or for FTP download.</para>
<para>Contact <link linkend="xig">Xi Graphics</link> for an
a.out &motif; 2.0 distribution for FreeBSD.</para>
<para>This distribution includes:</para>
<itemizedlist>
<listitem>
<para>OSF/&motif; manager, xmbind, panner, wsm.</para>
</listitem>
<listitem>
<para>Development kit with uil, mrm, xm, xmcxx, include
and Imake files.</para>
</listitem>
<listitem>
<para>Static and dynamic libraries (for use with FreeBSD
2.2.8 and earlier).</para>
</listitem>
<listitem>
<para>Demonstration applets.</para>
</listitem>
<listitem>
<para>Preformatted manual pages.</para>
</listitem>
</itemizedlist>
<para>Be sure to specify that you want the FreeBSD version
of &motif; when ordering! Versions for BSDI and &linux; are also
sold by <emphasis>Xi Graphics</emphasis>. This is currently a 4
diskette set... in the future this will change to a unified CD
distribution like their CDE.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="cde">
<para>Where can I get CDE for FreeBSD?</para>
</question>
<answer>
<para><link linkend="xig">Xi Graphics</link> used to sell CDE
for FreeBSD, but no longer do.</para>
<para><ulink url="http://www.kde.org/">KDE</ulink> is an open
source X11 desktop which is similar to CDE in many respects.
You might also like the look and feel of <ulink
url="http://www.xfce.org/">xfce</ulink>. KDE and xfce are both
in the <ulink url="&url.base;/ports/index.html">ports
system</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="commercial-xserver">
<para>Are there any commercial high-performance X servers?</para>
</question>
<answer>
<para>Yes, <ulink url="http://www.xig.com/">Xi Graphics</ulink>
and <ulink url="http://www.metrolink.com/">Metro Link</ulink>
sell Accelerated-X product for FreeBSD and other Intel based
systems.</para>
<para>The Metro Link offering is a high performance X Server
that offers easy configuration using the FreeBSD Package suite
of tools, support for multiple concurrent video boards and is
distributed in binary form only, in a convenient FTP download.
Not to mention the Metro Link offering is available at the very
reasonable price of $39. <anchor id="metrox"></para>
<para>Metro Link also sells both ELF and a.out &motif; for
FreeBSD (see above).</para>
<variablelist>
<varlistentry>
<term>More info</term>
<listitem>
<para><ulink url="http://www.metrolink.com/">
Metro Link WWW page</ulink></para>
</listitem>
</varlistentry>
<varlistentry>
<term>or</term>
<listitem>
<para><email>sales@metrolink.com</email>
or <email>tech@metrolink.com</email>
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>or</term>
<listitem>
<para>phone (954) 938-0283 or +1 954 938-0283</para>
</listitem>
</varlistentry>
</variablelist>
<para>The Xi Graphics offering is a high performance X Server
that offers easy configuration, support for multiple concurrent
video boards and is distributed in binary form only, in a
unified diskette distribution for FreeBSD and &linux;. Xi
Graphics also offers a high performance X Server tailored for
laptop support.<anchor id="xig"></para>
<para>There is a free <quote>compatibility demo</quote> of
version 5.0 available.</para>
<para>Xi Graphics also sells &motif; and CDE for FreeBSD (see
above).</para>
<variablelist>
<varlistentry>
<term>More info</term>
<listitem>
<para><ulink url="http://www.xig.com/">
Xi Graphics WWW page</ulink></para>
</listitem>
</varlistentry>
<varlistentry>
<term>or</term>
<listitem>
<para><email>sales@xig.com</email>
or <email>support@xig.com</email>
</para>
</listitem>
</varlistentry>
<varlistentry>
<term>or</term>
<listitem>
<para>phone (800) 946 7433 or +1 303 298-7478.</para>
</listitem>
</varlistentry>
</variablelist>
</answer>
</qandaentry>
<qandaentry>
<question id="database-systems">
<para>Are there any Database systems for FreeBSD?</para>
</question>
<answer>
<para>Yes! See the <ulink
url="&url.base;/commercial/software_bycat.html#CATEGORY_DATABASE">
Commercial Vendors</ulink> section of FreeBSD's Web site.</para>
<para>Also see the <ulink
url="&url.base;/ports/databases.html">
Databases</ulink> section of the Ports collection.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="oracle-support">
<para>Can I run &oracle; on FreeBSD?</para>
</question>
<answer>
<para>Yes. The following pages tell you exactly how to set up
&linux;-&oracle; on FreeBSD:</para>
<itemizedlist>
<listitem>
<para><ulink
url="http://www.scc.nl/~marcel/howto-oracle.html">
http://www.scc.nl/~marcel/howto-oracle.html</ulink></para>
</listitem>
<listitem>
<para><ulink
url="http://www.lf.net/lf/pi/oracle/install-linux-oracle-on-freebsd">
http://www.lf.net/lf/pi/oracle/install-linux-oracle-on-freebsd</ulink></para>
</listitem>
</itemizedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="commercial-webbrowsers">
<para>Are there any commercial web browsers available for &os;?</para>
</question>
<answer>
<para>Yes. Opera is a multi-platform web browser and is available for &os;.
See <ulink url="http://www.opera.com/">www.opera.com</ulink> for details.
A version of Opera, paid for by banner ads, is also available in ports.</para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter id="applications">
<title>User Applications</title>
<qandaset>
<qandaentry>
<question id="user-apps">
<para>So, where are all the user applications?</para>
</question>
<answer>
<para>Please take a look at <ulink
url="&url.base;/ports/index.html">the ports page</ulink>
for info on software packages ported to FreeBSD. The list
currently tops &os.numports; and is growing daily, so come
back to check often or subscribe to the
<literal>freebsd-announce</literal> <link
linkend="mailing">mailing list</link> for periodic updates
on new entries.</para>
<para>Most ports should work on the 4.X, 5.X, and 6.X branches.
Each time a FreeBSD release is made, a snapshot of the
ports tree at the time of release in also included in the
<filename>ports/</filename> directory.</para>
<para>We also support the concept of a
<quote>package</quote>, essentially no more than a compressed
binary distribution with a little extra intelligence
embedded in it for doing whatever custom installation work
is required. A package can be installed and uninstalled
again easily without having to know the gory details of
which files it includes.</para>
<para>Use the package installation menu in
<filename>/stand/sysinstall</filename> (under the
post-configuration menu item) or invoke the
&man.pkg.add.1; command on the specific package files you
are interested in installing. Package files can usually be
identified by their <filename>.tgz</filename> or <filename>.tbz</filename> suffix and
CDROM distribution people will have a
<filename>packages/All</filename> directory on their CD
which contains such files. They can also be downloaded
over the net for various versions of FreeBSD at the
following locations:</para>
<variablelist>
<varlistentry>
<term>for 4.X-RELEASE/4-STABLE</term>
<listitem>
<para><ulink
url="ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-stable/">
ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-stable/</ulink></para>
</listitem>
</varlistentry>
<varlistentry>
<term>for 5.X-RELEASE/5-STABLE</term>
<listitem>
<para><ulink
url="ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-5-current/">
ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-5-current</ulink></para>
</listitem>
</varlistentry>
<varlistentry>
<term>for 6-CURRENT</term>
<listitem>
<para><ulink
url="ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-6-current/">
ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-6-current</ulink></para>
</listitem>
</varlistentry>
</variablelist>
<para>or your nearest local mirror site.</para>
<para>Note that all ports may not be available as packages since
new ones are constantly being added. It is always a good idea
to check back periodically to see which packages are available
at the <ulink
url="ftp://ftp.FreeBSD.org/pub/FreeBSD/">ftp.FreeBSD.org</ulink>
master site.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="emul">
<para>Why does ghostscript give lots of errors with my
386/486SX?</para>
</question>
<answer>
<para>You do not have a math co-processor, right?
You will need to add the alternative math emulator to your
kernel; you do this by adding the following to your kernel
config file and it will be compiled in.</para>
<programlisting>options GPL_MATH_EMULATE</programlisting>
<note>
<para>You will need to remove the
<literal>MATH_EMULATE</literal> option when you do
this.</para>
</note>
</answer>
</qandaentry>
<qandaentry>
<question id="configure-inn">
<para>How do I configure INN (Internet News) for my machine?</para>
</question>
<answer>
<para>After installing the <filename
role="package">news/inn</filename> package or port, an
excellent place to start is <ulink
url="http://www.visi.com/~barr/INN.html">Dave
Barr's INN Page</ulink> where you will find the INN
FAQ.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="java">
<para>Does FreeBSD support &java;?</para>
</question>
<answer>
<para>Yes. Please see <ulink
url="&url.base;/java/index.html">
http://www.FreeBSD.org/java/</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ports-4x">
<para>Why can I not build this port on my 4.X-STABLE machine?</para>
</question>
<answer>
<para>If you are running a FreeBSD version that lags
significantly behind -CURRENT or -STABLE, you may need to
update your ports collection; see the <ulink
url="&url.books.porters-handbook;/keeping-up.html">
Keeping Up</ulink> section of the Porter's Handbook for further
information on how to do this.
If you are up to date,
then someone might have committed a change to the port which
works for -CURRENT but which broke the port for -STABLE. Please
submit a bug report on this with the
&man.send-pr.1; command, since the ports
collection is supposed to work for both the -CURRENT and
-STABLE branches.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="make-index">
<para>I just tried to build <filename>INDEX</filename>
using <command>make index</command>, and it failed.
Why?</para>
</question>
<answer>
<para>First, always make sure that you have a completely
up-to-date Ports Collection. Errors that affect building
<filename>INDEX</filename> from an up-to-date copy of the
Ports Collection are high-visibility and are thus almost
always fixed immediately.</para>
<para>However, if you are up-to-date, perhaps you are seeing
another problem. <command>make index</command> has a
known bug in dealing with incomplete copies of the Ports
Collection. It assumes that you have a local copy of every
single port that every other port that you have a local copy
of depends on. To explain, if you have a copy of
<filename>foo/bar</filename> on your disk, and
<filename>foo/bar</filename> depends on
<filename>baz/quux</filename>, then you must also have
a copy of <filename>baz/quux</filename> on your disk, and
the ports <filename>baz/quux</filename> depends on, and
so on. Otherwise, <command>make index</command> has
insufficient information to create its dependency tree.</para>
<para>This is particularly a problem for &os; users who
utilize &man.cvsup.1; to track the Ports Collection but
choose not to install certain categories by specifying
them in <filename>refuse</filename>. In theory, one
should be able to refuse categories, but in practice
there are too many ports that depend on ports in other
categories. Until someone comes up with a solution for
this problem, the general rule is is that if you want to
build <filename>INDEX</filename>, you must have a complete
copy of the Ports Collection.</para>
<para>There are rare cases where <filename>INDEX</filename>
will not build due to odd cases involving
<makevar>WITH_<replaceable>*</replaceable></makevar> or
<makevar>WITHOUT_<replaceable>*</replaceable></makevar>
variables being set in <filename>make.conf</filename>. If
you suspect that this is the case, please try to make
<filename>INDEX</filename> with those Makevars turned off
before reporting it to &a.ports;.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="cvsup-in-base">
<para>Why is CVSup not integrated in the main FreeBSD tree?
</para>
</question>
<answer>
<para>The FreeBSD base system is designed as self-hosting - it
should be possible to build the whole operating system starting
with a very limited set of tools. Thus, the actual build tools
needed to compile the FreeBSD sources are bundled with the
sources themselves. This includes a C compiler (&man.gcc.1;),
&man.make.1;, &man.awk.1;, and similar tools.</para>
<para>Since CVSup is written in Modula-3, adding it to the FreeBSD
base system would also require adding and maintaining a Modula-3
compiler. This would lead to both an increase in the disk space
consumed by the FreeBSD sources and additional maintenance work.
Thus, it is much easier for both the developers and users to
keep CVSup as a separate port, which can be easily installed as
a package bundled on the FreeBSD installation CDs.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ports-update">
<para>I updated the sources, now how do I update my installed
ports?</para>
</question>
<answer>
<para>FreeBSD does not include a port upgrading tool, but it
does have some tools to make the upgrade process somewhat
easier. You can also install additional tools to simplify
port handling.</para>
<para>The &man.pkg.version.1; command can generate a script
that will update installed ports to the latest version in
the ports tree.</para>
<screen>&prompt.root; <userinput>pkg_version -c &gt; <replaceable>/tmp/myscript</replaceable></userinput></screen>
<para>The output script <emphasis>must</emphasis> be edited by
hand before you use it. Recent versions of
&man.pkg.version.1; force this by inserting an
&man.exit.1; at the beginning of the script.</para>
<para>You should save the output of the script, as it will note
packages that depend on the one that has been updated. These
may or may not need to be updated as well. The usual case where
they need to be updated is that a shared library has changed
version numbers, so the ports that used that library need to be
rebuilt to use the new version.</para>
<note>
<para>Beginning with FreeBSD 5.0 (and higher revisions),
&man.pkg.version.1; no longer supports the
<option>-c</option> option.</para>
</note>
<para>If you have the disk space, you can use the
<command>portupgrade</command> tool to automate all of
this. <command>portupgrade</command> includes various
tools to simplify package handling. It is available under
<filename role="package">sysutils/portupgrade</filename>.
Since it is written in Ruby,
<command>portupgrade</command> is an unlikely candidate for
integration with the main FreeBSD tree. That should not
stop anyone from using it, however.</para>
<para>If your system is up full time, the &man.periodic.8; system
can be used to generate a weekly list of ports that might need
updating by setting
<literal>weekly_status_pkg_enable="YES"</literal> in
<filename>/etc/periodic.conf</filename>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="minimal-sh">
<para>Why is <command>/bin/sh</command> so minimal? Why does
FreeBSD not use <command>bash</command> or another shell?</para>
</question>
<answer>
<para>Because &posix; says that there shall be such a shell.</para>
<para>The more complicated answer: many people need to write shell
scripts which will be portable across many systems. That is why
&posix; specifies the shell and utility commands in great detail.
Most scripts are written in Bourne shell, and because several
important programming interfaces (&man.make.1;, &man.system.3;,
&man.popen.3;, and analogues in higher-level scripting
languages like Perl and Tcl) are specified to use the Bourne
shell to interpret commands. Because the Bourne shell is so
often and widely used, it is important for it to be quick to
start, be deterministic in its behavior, and have a small
memory footprint.</para>
<para>The existing implementation is our best effort at meeting as
many of these requirements simultaneously as we can. In order to
keep <command>/bin/sh</command> small, we have not provided many
of the convenience features that other shells have. That is why the
Ports Collection includes more featureful shells like bash, scsh,
tcsh, and zsh. (You can compare for yourself the memory
utilization of all these shells by looking at the
<quote>VSZ</quote> and <quote>RSS</quote> columns in a <command>ps
-u</command> listing.)</para>
</answer>
</qandaentry>
<qandaentry>
<question id="netscape-slow-startup">
<para>Why do &netscape; and Opera take so long to
start?</para>
</question>
<answer>
<para>The usual answer is that DNS on your system is
misconfigured. Both &netscape; and Opera perform DNS checks
when starting up. The browser will not appear on your
desktop until the program either gets a response or
determines that the system has no network
connection.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ports-base-update">
<para>I updated parts of the Ports Collection using CVSup, and
now many ports fail to build with mysterious error messages!
What happened? Is the Ports Collection broken in some major
way?</para>
</question>
<answer>
<para>If you only update parts of the Ports Collection, using
one of its CVSup subcollections and not the
<literal>ports-all</literal> CVSup collection, you should
<emphasis>always</emphasis> update the
<literal>ports-base</literal> subcollection too! The reasons
are described <ulink
url="&url.books.handbook;/cvsup.html#CVSUP-COLLEC-PBASE-WARN">in the
Handbook</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="midi-sound-files">
<para>How do I create audio CDs from my MIDI files?</para>
</question>
<answer><para>To create audio CDs from MIDI files, first
install <filename role="package">audio/timidity++</filename>
from ports then install manually the GUS patches set by Eric
A. Welsh, available at <ulink
url="http://www.stardate.bc.ca/eawpatches/html/default.htm"></ulink>.
After timidity++ has been installed properly, midi files may
be converted to wav files with the following command
line:</para>
<screen>&prompt.user; <userinput>timidity -Ow -s 44100 -o /tmp/juke/01.wav 01.mid</userinput></screen>
<para>The wav files can then be converted to other formats
or burned onto audio CDs, as described in the FreeBSD
Handbook.</para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter id="kernelconfig">
<title>Kernel Configuration</title>
<qandaset>
<qandaentry>
<question id="make-kernel">
<para>I would like to customize my kernel. Is it difficult?</para>
</question>
<answer>
<para>Not at all! Check out the <ulink
url="&url.books.handbook;/kernelconfig.html">
kernel config section of the Handbook</ulink>.</para>
<note>
<para>We recommend that you make a dated snapshot of
your new <filename>/kernel</filename> called
<filename>/kernel.YYMMDD</filename> after you get it
working properly. Also back up your new
<filename>/modules</filename> directory to
<filename>/modules.YYMMDD</filename>. That way, if
you make a mistake the next time you play with your
configuration you can boot the backup kernel instead
of having to fall back to
<filename>kernel.GENERIC</filename>. This is
particularly important if you are now booting from a
controller that GENERIC does not support.</para>
</note>
</answer>
</qandaentry>
<qandaentry>
<question id="missing-hw-float">
<para>My kernel compiles fail because
<literal>_hw_float</literal> is missing. How do I solve
this problem?</para>
</question>
<answer>
<para>You probably removed <devicename>npx0</devicename>
(see &man.npx.4;) from your kernel configuration file
because you do not have a math co-processor. The
<devicename>npx0</devicename> device is
<emphasis>MANDATORY</emphasis>. Somewhere inside your
hardware lies a device that provides hardware
floating-point support, even if it's no longer a separate
device as used in the good old 386 days. You
<emphasis>must</emphasis> include the
<devicename>npx0</devicename> device. Even if you manage
to build a kernel without <devicename>npx0</devicename>
support, it won't boot anyway. </para>
</answer>
</qandaentry>
<qandaentry>
<question id="why-kernel-big">
<para>Why is my kernel so big (over 10MB)?</para>
</question>
<answer>
<para>Chances are, you compiled your kernel in
<emphasis>debug mode</emphasis>. Kernels built in debug
mode contain many symbols that are used for debugging,
thus greatly increasing the size of the kernel. Note that
there will be little or no performance decrease from
running a debug kernel, and it is useful to keep one
around in case of a system panic.</para>
<para>However, if you are running low on disk space, or
you simply do not want to run a debug kernel, make sure
that both of the following are true:</para>
<itemizedlist>
<listitem>
<para>You do not have a line in your kernel
configuration file that reads:</para>
<programlisting>makeoptions DEBUG=-g</programlisting>
</listitem>
<listitem>
<para>You are not running &man.config.8; with
the <option>-g</option> option.</para>
</listitem>
</itemizedlist>
<para>Either of the above settings will cause your kernel to
be built in debug mode. As long as you make sure you
follow the steps above, you can build your kernel
normally, and you should notice a fairly large size
decrease; most kernels tend to be around 1.5MB to
2MB.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="multiport-serial-interrupts">
<para>Why do I get interrupt conflicts with multi-port serial
code?</para>
</question>
<answer>
<para>When I compile a kernel
with multi-port serial code, it tells me that only the first
port is probed and the rest skipped due to interrupt conflicts.
How do I fix this?</para>
<para>The problem here is that
FreeBSD has code built-in to keep the kernel from getting
trashed due to hardware or software conflicts. The way to fix
this is to leave out the IRQ settings on all but one port. Here
is an example:</para>
<programlisting>#
# Multiport high-speed serial line - 16550 UARTS
#
device sio2 at isa? port 0x2a0 tty irq 5 flags 0x501 vector siointr
device sio3 at isa? port 0x2a8 tty flags 0x501 vector siointr
device sio4 at isa? port 0x2b0 tty flags 0x501 vector siointr
device sio5 at isa? port 0x2b8 tty flags 0x501 vector siointr</programlisting>
</answer>
</qandaentry>
<qandaentry>
<question id="generic-kernel-build-failure">
<para>Why does every kernel I try to build fail to compile, even
GENERIC?</para>
</question>
<answer>
<para>There are a number of possible causes for this problem.
They are, in no particular order:</para>
<itemizedlist>
<listitem>
<para>You are not using the new <command>make
buildkernel</command> and <command>make
installkernel</command> targets, and your source tree is
different from the one used to build the currently running
system (e.g., you are compiling 4.3-RELEASE on a 4.0-RELEASE
system). If you are attempting an upgrade, please read the
<filename>/usr/src/UPDATING</filename> file, paying
particular attention to the <quote>COMMON ITEMS</quote>
section at the end.</para>
</listitem>
<listitem>
<para>You are using the new <command>make
buildkernel</command> and <command>make
installkernel</command> targets, but you failed to assert
the completion of the <command>make buildworld</command>
target. The <command>make buildkernel</command> target
relies on files generated by the <command>make
buildworld</command> target to complete its job
correctly.</para>
</listitem>
<listitem>
<para>Even if you are trying to build <link
linkend="stable">FreeBSD-STABLE</link>, it is possible that
you fetched the source tree at a time when it was either
being modified, or broken for other reasons; only releases
are absolutely guaranteed to be buildable, although <link
linkend="stable">FreeBSD-STABLE</link> builds fine the
majority of the time. If you have not already done so, try
re-fetching the source tree and see if the problem goes
away. Try using a different server in case the one you are
using is having problems.</para>
</listitem>
</itemizedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="scheduler-in-use">
<para>How can I verify which scheduler is in use on a
running system?</para>
</question>
<answer>
<para>If you are running &os; version 5.2.1 or earlier, check for
the existence of the <literal>kern.quantum</literal> sysctl.
If you have it, you should see something like this:</para>
<screen>&prompt.user; sysctl <replaceable>kern.quantum</replaceable>
kern.sched.quantum: 99960</screen>
<para>If the <literal>kern.quantum</literal> sysctl exists, you are
using the 4BSD scheduler. If not, you will get an error printed
by &man.sysctl.8; (which you can safely ignore):</para>
<screen>&prompt.user; sysctl <replaceable>kern.sched.quantum</replaceable>
sysctl: unknown oid 'kern.sched.quantum'</screen>
<para>In &os; version 5.3-RELEASE and later, the name of the
scheduler currently being used is directly available as the value
of the <literal>kern.sched.name</literal> sysctl:</para>
<screen>&prompt.user; sysctl <replaceable>kern.sched.name</replaceable>
kern.sched.name: 4BSD</screen>
</answer>
</qandaentry>
<qandaentry>
<question id="scheduler-kern-quantum">
<para>What is <literal>kern.quantum</literal>?</para>
</question>
<answer>
<para><literal>kern.quantum</literal> is the maximum number of
ticks a process can run without being preempted. It is
specific to the 4BSD scheduler, so you can use its
presence or absence to determine which scheduler is in
use. In &os; 5.X or later <literal>kern.quantum</literal> has
been renamed to <literal>kern.sched.quantum</literal>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="scheduler-kern-sched-quantum">
<para>What is <literal>kern.sched.quantum</literal>?</para>
</question>
<answer>
<para>See <xref linkend="scheduler-kern-quantum"></para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter id="disks">
<title>Disks, Filesystems, and Boot Loaders</title>
<qandaset>
<qandaentry>
<question id="adding-disks">
<para>How can I add my new hard disk to my FreeBSD system?</para>
</question>
<answer>
<para>See the Disk Formatting Tutorial at <ulink
url="&url.articles.formatting-media;/index.html">
www.FreeBSD.org</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="new-huge-disk">
<para>How do I move my system over to my huge new disk?</para>
</question>
<answer>
<para>The best way is to reinstall the OS on the new
disk, then move the user data over. This is highly
recommended if you have been tracking -STABLE for more
than one release, or have updated a release instead of
installing a new one. You can install booteasy on both
disks with &man.boot0cfg.8;, and dual boot them until
you are happy with the new configuration. Skip the
next paragraph to find out how to move the data after
doing this.</para>
<para>Should you decide not to do a fresh install, you
need to partition and label the new disk with either
<filename>/stand/sysinstall</filename>, or &man.fdisk.8;
and &man.disklabel.8;. You should also install booteasy
on both disks with &man.boot0cfg.8;, so that you can
dual boot to the old or new system after the copying
is done. See the <ulink
url="&url.articles.formatting-media;/index.html">
formatting-media article</ulink> for details on this
process.</para>
<para>Now you have the new disk set up, and are ready
to move the data. Unfortunately, you cannot just blindly
copy the data. Things like device files (in
<filename>/dev</filename>), flags, and links tend to
screw that up. You need to use tools that understand
these things, which means &man.dump.8;.
Although it is suggested that you move the data in single user
mode, it is not required.</para>
<para>You should never use anything but &man.dump.8; and
&man.restore.8; to move the root filesystem. The
&man.tar.1; command may work - then again, it may not.
You should also use &man.dump.8; and &man.restore.8;
if you are moving a single partition to another empty
partition. The sequence of steps to use dump to move
a partitions data to a new partition is:</para>
<procedure>
<step>
<para>newfs the new partition.</para>
</step>
<step>
<para>mount it on a temporary mount point.</para>
</step>
<step>
<para>cd to that directory.</para>
</step>
<step>
<para>dump the old partition, piping output to the
new one.</para>
</step>
</procedure>
<para>For example, if you are going to move root to
<devicename>/dev/ad1s1a</devicename>, with
<filename>/mnt</filename> as the temporary mount point,
it is:</para>
<screen>&prompt.root; <userinput>newfs /dev/ad1s1a</userinput>
&prompt.root; <userinput>mount /dev/ad1s1a /mnt</userinput>
&prompt.root; <userinput>cd /mnt</userinput>
&prompt.root; <userinput>dump 0af - / | restore xf -</userinput></screen>
<para>Rearranging your partitions with dump takes a bit more
work. To merge a partition like <filename>/var</filename>
into its parent, create the new partition large enough
for both, move the parent partition as described above,
then move the child partition into the empty directory
that the first move created:</para>
<screen>&prompt.root; <userinput>newfs /dev/ad1s1a</userinput>
&prompt.root; <userinput>mount /dev/ad1s1a /mnt</userinput>
&prompt.root; <userinput>cd /mnt</userinput>
&prompt.root; <userinput>dump 0af - / | restore xf -</userinput>
&prompt.root; <userinput>cd var</userinput>
&prompt.root; <userinput>dump 0af - /var | restore xf -</userinput></screen>
<para>To split a directory from its parent, say putting
<filename>/var</filename> on its own partition when it was not
before, create both partitions, then mount the child partition
on the appropriate directory in the temporary mount point, then
move the old single partition:</para>
<screen>&prompt.root; <userinput>newfs /dev/ad1s1a</userinput>
&prompt.root; <userinput>newfs /dev/ad1s1d</userinput>
&prompt.root; <userinput>mount /dev/ad1s1a /mnt</userinput>
&prompt.root; <userinput>mkdir /mnt/var</userinput>
&prompt.root; <userinput>mount /dev/ad1s1d /mnt/var</userinput>
&prompt.root; <userinput>cd /mnt</userinput>
&prompt.root; <userinput>dump 0af - / | restore xf -</userinput></screen>
<para>You might prefer &man.cpio.1;, &man.pax.1;,
&man.tar.1; to &man.dump.8; for user data. At the time of
this writing, these are known to lose file flag information,
so use them with caution.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="dangerously-dedicated">
<para>Will a <quote>dangerously dedicated</quote> disk endanger
my health?</para>
</question>
<answer>
<para><anchor id="dedicate">The installation procedure allows
you to chose two different methods in partitioning your
hard disk(s). The default way makes it compatible with other
operating systems on the same machine, by using fdisk table
entries (called <quote>slices</quote> in FreeBSD), with a
FreeBSD slice that employs partitions of its own. Optionally,
one can chose to install a boot-selector to switch between the
possible operating systems on the disk(s). The alternative uses
the entire disk for FreeBSD, and makes no attempt to be
compatible with other operating systems.</para>
<para>So why it is called <quote>dangerous</quote>? A disk
in this mode does not contain what normal PC utilities
would consider a valid fdisk table. Depending on how well
they have been designed, they might complain at you once
they are getting in contact with such a disk, or even
worse, they might damage the BSD bootstrap without even
asking or notifying you. In addition, the
<quote>dangerously dedicated</quote> disk's layout is
known to confuse many BIOSes, including those from AWARD
(e.g. as found in HP Netserver and Micronics systems as
well as many others) and Symbios/NCR (for the popular
53C8xx range of SCSI controllers). This is not a complete
list, there are more. Symptoms of this confusion include
the <errorname>read error</errorname> message printed by
the FreeBSD bootstrap when it cannot find itself, as well
as system lockups when booting.</para>
<para>Why have this mode at all then? It only saves a few kbytes
of disk space, and it can cause real problems for a new
installation. <quote>Dangerously dedicated</quote> mode's
origins lie in a desire to avoid one of the most common
problems plaguing new FreeBSD installers - matching the BIOS
<quote>geometry</quote> numbers for a disk to the disk
itself.</para>
<para><quote>Geometry</quote> is an outdated concept, but one
still at the heart of the PC's BIOS and its interaction with
disks. When the FreeBSD installer creates slices, it has to
record the location of these slices on the disk in a fashion
that corresponds with the way the BIOS expects to find them. If
it gets it wrong, you will not be able to boot.</para>
<para><quote>Dangerously dedicated</quote> mode tries to work
around this by making the problem simpler. In some cases, it
gets it right. But it is meant to be used as a last-ditch
alternative - there are better ways to solve the problem 99
times out of 100.</para>
<para>So, how do you avoid the need for <quote>DD</quote> mode
when you are installing? Start by making a note of the geometry
that your BIOS claims to be using for your disks. You can
arrange to have the kernel print this as it boots by specifying
<option>-v</option> at the <literal>boot:</literal> prompt, or
using <command>boot -v</command> in the loader. Just before the
installer starts, the kernel will print a list of BIOS
geometries. Do not panic - wait for the installer to start and
then use scrollback to read the numbers. Typically the BIOS
disk units will be in the same order that FreeBSD lists your
disks, first IDE, then SCSI.</para>
<para>When you are slicing up your disk, check that the disk
geometry displayed in the FDISK screen is correct (ie. it
matches the BIOS numbers); if it is wrong, use the
<keycap>g</keycap> key to fix it. You may have to do this if
there is absolutely nothing on the disk, or if the disk has been
moved from another system. Note that this is only an issue with
the disk that you are going to boot from; FreeBSD will sort
itself out just fine with any other disks you may have.</para>
<para>Once you have got the BIOS and FreeBSD agreeing about the
geometry of the disk, your problems are almost guaranteed to be
over, and with no need for <quote>DD</quote> mode at all. If,
however, you are still greeted with the dreaded <errorname>read
error</errorname> message when you try to boot, it is time to cross
your fingers and go for it - there is nothing left to
lose.</para>
<para>To return a <quote>dangerously dedicated</quote> disk
for normal PC use, there are basically two options. The first
is, you write enough NULL bytes over the MBR to make any
subsequent installation believe this to be a blank disk. You
can do this for example with</para>
<screen>&prompt.root; <userinput>dd if=/dev/zero of=/dev/rda0 count=15</userinput></screen>
<para>Alternatively, the undocumented DOS
<quote>feature</quote></para>
<screen><prompt>C:\&gt;</prompt> <userinput>fdisk /mbr</userinput></screen>
<para>will to install a new master boot record as well, thus
clobbering the BSD bootstrap.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="safe-softupdates">
<para>Which partitions can safely use Soft Updates? I have
heard that Soft Updates on <filename>/</filename> can cause
problems.</para>
</question>
<answer>
<para>Short answer: you can usually use Soft Updates safely
on all partitions.</para>
<para>Long answer: There used to be some concern over using
Soft Updates on the root partition. Soft Updates has two
characteristics that caused this. First, a Soft Updates
partition has a small chance of losing data during a
system crash. (The partition will not be corrupted; the
data will simply be lost.) Also, Soft Updates can cause
temporary space shortages.</para>
<para>When using Soft Updates, the kernel can take up to
thirty seconds to actually write changes to the physical
disk. If you delete a large file, the file still resides
on disk until the kernel actually performs the deletion.
This can cause a very simple race condition. Suppose you
delete one large file and immediately create another large
file. The first large file is not yet actually removed
from the physical disk, so the disk might not have enough
room for the second large file. You get an error that the
partition does not have enough space, although you know
perfectly well that you just released a large chunk of
space! When you try again mere seconds later, the file
creation works as you expect. This has left more than one
user scratching his head and doubting his sanity, the
FreeBSD filesystem, or both.</para>
<para>If a system should crash after the kernel accepts a
chunk of data for writing to disk, but before that data is
actually written out, data could be lost or corrupted.
This risk is extremely small, but generally manageable.
Use of IDE write caching greatly increases this risk; it
is strongly recommended that you disable IDE write caching
when using Soft Updates.</para>
<para>These issues affect all partitions using Soft Updates.
So, what does this mean for the root partition?</para>
<para>Vital information on the root partition changes very
rarely. Files such as <filename>/kernel</filename> and
the contents of <filename>/etc</filename> only change
during system maintenance, or when users change their
passwords. If the system crashed during the
thirty-second window after such a change is made, it is
possible that data could be lost. This risk is negligible
for most applications, but you should be aware that it
exists. If your system cannot tolerate this much risk,
do not use Soft Updates on the root filesystem!</para>
<para><filename>/</filename> is traditionally one of the
smallest partitions. By default, FreeBSD puts the
<filename>/tmp</filename> directory on
<filename>/</filename>. If you have a busy
<filename>/tmp</filename>, you might see intermittent
space problems. Symlinking <filename>/tmp</filename> to
<filename>/var/tmp</filename> will solve this
problem.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="inappropriate-ccd">
<para>What is inappropriate about my ccd?</para>
</question>
<answer>
<para>The symptom of this is:</para>
<screen>&prompt.root; <userinput>ccdconfig -C</userinput>
ccdconfig: ioctl (CCDIOCSET): /dev/ccd0c: Inappropriate file type or format</screen>
<para>This usually happens when you are trying to concatenate
the <literal>c</literal> partitions, which default to type
<literal>unused</literal>. The ccd driver requires the
underlying partition type to be FS_BSDFFS. Edit the disklabel
of the disks you are trying to concatenate and change the types
of partitions to <literal>4.2BSD</literal>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ccd-disklabel">
<para>Why can I not edit the disklabel on my ccd?</para>
</question>
<answer>
<para>The symptom of this is:</para>
<screen>&prompt.root; <userinput>disklabel ccd0</userinput>
(it prints something sensible here, so let us try to edit it)
&prompt.root; <userinput>disklabel -e ccd0</userinput>
(edit, save, quit)
disklabel: ioctl DIOCWDINFO: No disk label on disk;
use "disklabel -r" to install initial label</screen>
<para>This is because the disklabel returned by ccd is actually
a <quote>fake</quote> one that is not really on the disk.
You can solve this problem by writing it back explicitly,
as in:</para>
<screen>&prompt.root; <userinput>disklabel ccd0 &gt; /tmp/disklabel.tmp</userinput>
&prompt.root; <userinput>disklabel -Rr ccd0 /tmp/disklabel.tmp</userinput>
&prompt.root; <userinput>disklabel -e ccd0</userinput>
(this will work now)</screen>
</answer>
</qandaentry>
<qandaentry>
<question id="mount-foreign-fs">
<para>Can I mount other foreign filesystems under FreeBSD?</para>
</question>
<answer>
<variablelist>
<varlistentry>
<term>Digital UNIX</term>
<listitem>
<para>UFS CDROMs can be mounted directly on FreeBSD.
Mounting disk partitions from Digital UNIX and other
systems that support UFS may be more complex, depending
on the details of the disk partitioning for the operating
system in question.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>&linux;</term>
<listitem>
<para>FreeBSD supports <literal>ext2fs</literal>
partitions. See &man.mount.ext2fs.8; for more
information.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>&windowsnt;</term>
<listitem>
<para>FreeBSD includes a read-only NTFS driver. For
more information, see &man.mount.ntfs.8;.
</para>
</listitem>
</varlistentry>
</variablelist>
<para>Any other information on this subject would be
appreciated.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="mount-dos">
<para>How do I mount a secondary DOS partition?</para>
</question>
<answer>
<para>The secondary DOS partitions are found after ALL the
primary partitions. For example, if you have an
<quote>E</quote> partition as the second DOS partition on
the second SCSI drive, you need to create the special files
for <quote>slice 5</quote> in <filename>/dev</filename>,
then mount <devicename>/dev/da1s5</devicename>:</para>
<screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>sh MAKEDEV da1s5</userinput>
&prompt.root; <userinput>mount -t msdos /dev/da1s5 /dos/e</userinput></screen>
<note>
<para>You can omit this step if you are running FreeBSD
5.0-RELEASE or newer with &man.devfs.5;
enabled.</para>
</note>
</answer>
</qandaentry>
<qandaentry>
<question id="crypto-filesystem">
<para>Is there a cryptographic filesystem for &os;?</para>
</question>
<answer>
<para>Yes. If you are running FreeBSD 5.0 or later, see
&man.gbde.8;. For earlier releases, see the <filename
role="package">security/cfs</filename> port.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="nt-bootloader">
<para>How can I use the &windowsnt; loader to boot FreeBSD?</para>
</question>
<answer>
<para>The general idea is that you copy the first sector of your
native root FreeBSD partition into a file in the DOS/&windowsnt;
partition. Assuming you name that file something like
<filename>c:\bootsect.bsd</filename> (inspired by
<filename>c:\bootsect.dos</filename>), you can then edit the
<filename>c:\boot.ini</filename> file to come up with something
like this:</para>
<programlisting>[boot loader]
timeout=30
default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS
[operating systems]
multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows NT"
C:\BOOTSECT.BSD="FreeBSD"
C:\="DOS"</programlisting>
<para>If FreeBSD is installed on the same disk as the &windowsnt; boot
partition simply copy <filename>/boot/boot1</filename> to
<filename>C:\BOOTSECT.BSD</filename>. However, if FreeBSD is
installed on a different disk <filename>/boot/boot1</filename>
will not work, <filename>/boot/boot0</filename> is needed.</para>
<para><filename>/boot/boot0</filename> needs to be installed
using sysinstall by selecting the FreeBSD boot manager on
the screen which asks if you wish to use a boot
manager. This is because <filename>/boot/boot0</filename>
has the partition table area filled with NULL characters
but sysinstall copies the partition table before copying
<filename>/boot/boot0</filename> to the MBR.</para>
<warning>
<para><emphasis>Do not simply copy <filename>/boot/boot0</filename>
instead of <filename>/boot/boot1</filename>; you will
overwrite your partition table and render your computer
un-bootable!</emphasis></para>
</warning>
<para>When the FreeBSD boot manager runs it records the last
OS booted by setting the active flag on the partition table
entry for that OS and then writes the whole 512-bytes of itself
back to the MBR so if you just copy
<filename>/boot/boot0</filename> to
<filename>C:\BOOTSECT.BSD</filename> then it writes an empty
partition table, with the active flag set on one entry, to the
MBR.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="lilo-bootloader">
<para>How do I boot FreeBSD and &linux; from LILO?</para>
</question>
<answer>
<para>If you have FreeBSD and &linux; on the same disk, just follow
LILO's installation instructions for booting a non-&linux;
operating system. Very briefly, these are:</para>
<para>Boot &linux;, and add the following lines to
<filename>/etc/lilo.conf</filename>:</para>
<programlisting>other=/dev/hda2
table=/dev/hda
label=FreeBSD</programlisting>
<para>(the above assumes that your FreeBSD slice is known to
&linux; as <devicename>/dev/hda2</devicename>; tailor to
suit your setup). Then, run <command>lilo</command> as
<username>root</username> and you should be done.</para>
<para>If FreeBSD resides on another disk, you need to add
<literal>loader=/boot/chain.b</literal> to the LILO entry.
For example:</para>
<programlisting>other=/dev/dab4
table=/dev/dab
loader=/boot/chain.b
label=FreeBSD</programlisting>
<para>In some cases you may need to specify the BIOS drive number
to the FreeBSD boot loader to successfully boot off the second
disk. For example, if your FreeBSD SCSI disk is probed by BIOS
as BIOS disk 1, at the FreeBSD boot loader prompt you need to
specify:</para>
<screen>Boot: <userinput>1:da(0,a)/kernel</userinput></screen>
<para>On FreeBSD 2.2.5 and later, you can configure
&man.boot.8;
to automatically do this for you at boot time.</para>
<para>The <ulink
url="http://sunsite.unc.edu/LDP/HOWTO/mini/Linux+FreeBSD.html">
&linux;+FreeBSD mini-HOWTO</ulink> is a good reference for
FreeBSD and &linux; interoperability issues.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="booteasy-loader">
<para>How do I boot FreeBSD and &linux; using BootEasy?</para>
</question>
<answer>
<para>Install LILO at the start of your &linux; boot partition
instead of in the Master Boot Record. You can then boot LILO
from BootEasy.</para>
<para>If you are running &windows; 95 and &linux; this is recommended
anyway, to make it simpler to get &linux; booting again if you
should need to reinstall &windows; 95 (which is a Jealous
Operating System, and will bear no other Operating Systems in
the Master Boot Record).</para>
</answer>
</qandaentry>
<qandaentry>
<question id="changing-bootprompt">
<para>How do I change the boot prompt from <literal>???</literal> to
something more meaningful?</para>
</question>
<answer>
<para>You can not do that with the standard boot manager without
rewriting it. There are a number of other boot managers
in the <filename>sysutils</filename> ports category that
provide this functionality.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="removable-drives">
<para>I have a new removable drive, how do I use it?</para>
</question>
<answer>
<para>Whether it is a removable drive like a &iomegazip; or an EZ drive
(or even a floppy, if you want to use it that way), or a new
hard disk, once it is installed and recognized by the system,
and you have your cartridge/floppy/whatever slotted in, things
are pretty much the same for all devices.</para>
<para><anchor id="disklabel">(this section is based on <ulink
url="http://www.vmunix.com/mark/FreeBSD/ZIP-FAQ.html">
Mark Mayo's ZIP FAQ</ulink>)</para>
<para>If it is a ZIP drive or a floppy, you have already got a DOS
filesystem on it, you can use a command like this:</para>
<screen>&prompt.root; <userinput>mount -t msdos /dev/fd0c /floppy</userinput></screen>
<para>if it is a floppy, or this:</para>
<screen>&prompt.root; <userinput>mount -t msdos /dev/da2s4 /zip</userinput></screen>
<para>for a ZIP disk with the factory configuration.</para>
<para>For other disks, see how they are laid out using
&man.fdisk.8; or
&man.sysinstall.8;.</para>
<para>The rest of the examples will be for a ZIP drive on da2,
the third SCSI disk.</para>
<para>Unless it is a floppy, or a removable you plan on sharing
with other people, it is probably a better idea to stick a BSD
filesystem on it. You will get long filename support, at least a
2X improvement in performance, and a lot more stability. First,
you need to redo the DOS-level partitions/filesystems. You can
either use &man.fdisk.8; or
<filename>/stand/sysinstall</filename>, or for a small drive
that you do not want to bother with multiple operating system
support on, just blow away the whole FAT partition table
(slices) and just use the BSD partitioning:</para>
<screen>&prompt.root; <userinput>dd if=/dev/zero of=/dev/rda2 count=2</userinput>
&prompt.root; <userinput>disklabel -Brw da2 auto</userinput></screen>
<para>You can use disklabel or
<filename>/stand/sysinstall</filename> to create multiple BSD
partitions. You will certainly want to do this if you are adding
swap space on a fixed disk, but it is probably irrelevant on a
removable drive like a ZIP.</para>
<para>Finally, create a new filesystem, this one is on our ZIP
drive using the whole disk:</para>
<screen>&prompt.root; <userinput>newfs /dev/rda2c</userinput></screen>
<para>and mount it:</para>
<screen>&prompt.root; <userinput>mount /dev/da2c /zip</userinput></screen>
<para>and it is probably a good idea to add a line like this
to <filename>/etc/fstab</filename> (see &man.fstab.5;) so
you can just type <command>mount /zip</command> in the
future:</para>
<programlisting>/dev/da2c /zip ffs rw,noauto 0 0</programlisting>
</answer>
</qandaentry>
<qandaentry>
<question id="mount-cd-superblock">
<para>Why do I get <errorname>Incorrect super block</errorname> when
mounting a CDROM?</para>
</question>
<answer>
<para>You have to tell &man.mount.8; the type of the device
that you want to mount. This is described in the <ulink
url="&url.books.handbook;/creating-cds.html"> Handbook section on
optical media</ulink>, specifically the section <ulink
url="&url.books.handbook;/creating-cds.html#MOUNTING-CD">Using Data
CDs</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="cdrom-not-configured">
<para>Why do I get <errorname>Device not
configured</errorname> when mounting a CDROM?</para>
</question>
<answer>
<para>This generally means that there is no CDROM in the
CDROM drive, or the drive is not visible on the
bus. Please see the <ulink
url="&url.books.handbook;/creating-cds.html#MOUNTING-CD">Using Data
CDs</ulink> section of the Handbook for a detailed
discussion of this issue.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="cdrom-unicode-filenames">
<para>Why do all non-English characters in filenames show up as
<quote>?</quote> on my CDs when mounted in FreeBSD?</para>
</question>
<answer>
<para>Your CDROM probably uses the <quote>Joliet</quote>
extension for storing information about files and
directories. This is discussed in the Handbook chapter on
<ulink url="&url.books.handbook;/creating-cds.html">creating and
using CDROMs</ulink>, specifically the section on <ulink
url="&url.books.handbook;/creating-cds.html#MOUNTING-CD">Using Data
CDROMs</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="burncd-isofs">
<para>I burned a CD under FreeBSD and now I can not read it
under any other operating system. Why?</para>
</question>
<answer>
<para>You most likely burned a raw file to your CD, rather
than creating an ISO 9660 filesystem. Take a look at the
<ulink url="&url.books.handbook;/creating-cds.html">Handbook
chapter on creating CDROMs</ulink>, particularly the
section on <ulink
url="&url.books.handbook;/creating-cds.html#RAWDATA-CD">burning raw
data CDs</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="copy-cd">
<para>How can I create an image of a data CD?</para>
</question>
<answer>
<para>This is discussed in the Handbook section on <ulink
url="&url.books.handbook;/creating-cds.html#IMAGING-CD">duplicating
data CDs</ulink>. For more on working with CDROMs, see the
<ulink url="&url.books.handbook;/creating-cds.html">Creating CDs
Section</ulink> in the Storage chapter in the
Handbook.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="mount-audio-CD">
<para>Why can I not <command>mount</command> an audio
CD?</para>
</question>
<answer>
<para>If you try to mount an audio CD, you will get an error
like <errorname>cd9660: /dev/acd0c: Invalid
argument</errorname>. This is because
<command>mount</command> only works on filesystems. Audio
CDs do not have filesystems; they just have data. You
need a program that reads audio CDs, such as the
<filename role="package">audio/xmcd</filename> port.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="multi-session-CD">
<para>How do I <command>mount</command> a multi-session CD?</para>
</question>
<answer>
<para>By default, &man.mount.8; will attempt to mount the
last data track (session) of a CD. If you would like to
load an earlier session, you must use the
<option>-s</option> command line argument. Please see
&man.mount.cd9660.8; for specific examples.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="user-floppymount">
<para>How do I let ordinary users mount floppies, CDROMs and
other removable media?</para>
</question>
<answer>
<para>Ordinary users can be permitted to mount devices. Here is
how:</para>
<procedure>
<step>
<para>As <username>root</username> set the sysctl variable
<varname>vfs.usermount</varname> to
<literal>1</literal>.</para>
<screen>&prompt.root; <userinput>sysctl -w vfs.usermount=1</userinput></screen>
</step>
<step>
<para>As <username>root</username> assign the appropriate
permissions to the block device associated with the
removable media.</para>
<para>For example, to allow users to mount the first floppy
drive, use:</para>
<screen>&prompt.root; <userinput>chmod 666 /dev/fd0</userinput></screen>
<para>To allow users in the group
<groupname>operator</groupname> to mount the CDROM drive,
use:</para>
<screen>&prompt.root; <userinput>chgrp operator /dev/acd0c</userinput>
&prompt.root; <userinput>chmod 640 /dev/acd0c</userinput></screen>
</step>
<step>
<para>If you are running &os; 5.X or later, you will need to alter
<filename>/etc/devfs.conf</filename> to make these changes
permanent across reboots.</para>
<para>As <username>root</username>, add the necessary lines to
<filename>/etc/devfs.conf</filename>. For example, to allow
users to mount the first floppy drive add:</para>
<programlisting># Allow all users to mount the floppy disk.
own /dev/fd0 root:operator
perm /dev/fd0 0666</programlisting>
<para>To allow users in the group <groupname>operator</groupname>
to mount the CD-ROM drive add:</para>
<programlisting># Allow members of the group operator to mount CD-ROMs.
own /dev/acd0 root:operator
perm /dev/acd0 0660</programlisting>
</step>
<step>
<para>Finally, add the line
<literal><varname>vfs.usermount</varname>=1</literal>
to the file <filename>/etc/sysctl.conf</filename> so
that it is reset at system boot time.</para>
</step>
</procedure>
<para>All users can now mount the floppy
<devicename>/dev/fd0</devicename> onto a directory that they
own:</para>
<screen>&prompt.user; <userinput>mkdir ~/my-mount-point</userinput>
&prompt.user; <userinput>mount -t msdos /dev/fd0 ~/my-mount-point</userinput></screen>
<para>Users in group <groupname>operator</groupname> can now
mount the CDROM <devicename>/dev/acd0c</devicename> onto a
directory that they own:</para>
<screen>&prompt.user; <userinput>mkdir ~/my-mount-point</userinput>
&prompt.user; <userinput>mount -t cd9660 /dev/acd0c ~/my-mount-point</userinput></screen>
<para>Unmounting the device is simple:</para>
<screen>&prompt.user; <userinput>umount ~/my-mount-point</userinput></screen>
<para>Enabling <varname>vfs.usermount</varname>, however,
has negative security implications. A better way to
access &ms-dos; formatted media is to use the
<filename role="package">emulators/mtools</filename>
package in the ports collection.</para>
<note>
<para>The device name used in the previous examples must be
changed according to your configuration.</para>
</note>
</answer>
</qandaentry>
<qandaentry>
<question id="du-vs-df">
<para>The <command>du</command> and <command>df</command>
commands show different amounts of disk space available.
What is going on?</para>
</question>
<answer>
<para>You need to understand what <command>du</command> and
<command>df</command> really do. <command>du</command>
goes through the directory tree, measures how large each
file is, and presents the totals. <command>df</command>
just asks the filesystem how much space it has left. They
seem to be the same thing, but a file without a directory
entry will affect <command>df</command> but not
<command>du</command>.</para>
<para>When a program is using a file, and you delete the
file, the file is not really removed from the filesystem
until the program stops using it. The file is immediately
deleted from the directory listing, however. You can see
this easily enough with a program such as
<command>more</command>. Assume you have a file large
enough that its presence affects the output of
<command>du</command> and <command>df</command>. (Since
disks can be so large today, this might be a
<emphasis>very</emphasis> large file!) If you delete this
file while using <command>more</command> on it,
<command>more</command> does not immediately choke and
complain that it cannot view the file. The entry is
simply removed from the directory so no other program or
user can access it. <command>du</command> shows that it
is gone &mdash; it has walked the directory tree and the file
is not listed. <command>df</command> shows that it is
still there, as the filesystem knows that
<command>more</command> is still using that space. Once
you end the <command>more</command> session,
<command>du</command> and <command>df</command> will
agree.</para>
<para>Note that Soft Updates can delay the freeing of disk
space; you might need to wait up to 30 seconds for the
change to be visible!</para>
<para>This situation is common on web servers. Many people
set up a FreeBSD web server and forget to rotate the log
files. The access log fills up <filename>/var</filename>.
The new administrator deletes the file, but the system
still complains that the partition is full. Stopping and
restarting the web server program would free the file,
allowing the system to release the disk space. To prevent
this from happening, set up &man.newsyslog.8;.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="add-swap-space">
<para>How can I add more swap space?</para>
</question>
<answer>
<para>In the <ulink
url="&url.books.handbook;/config-tuning.html">Configuration and
Tuning</ulink> section of the Handbook, you will find a
<ulink
url="&url.books.handbook;/adding-swap-space.html">section</ulink>
describing how to do this.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="manufacturer-disk-size">
<para>Why does &os; see my disk as smaller than the
manufacturer says it is?</para>
</question>
<answer>
<para>Disk manufacturers calculate gigabytes as a billion bytes
each, whereas &os; calculates them as 1,073,741,824 bytes
each. This explains why, for example, &os;'s boot messages
will report a disk that supposedly has 80GB as holding
76319MB.</para>
<para>Also note that &os; will (by default)
<link linkend="disk-more-than-full">reserve</link> 8% of the disk
space.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="disk-more-than-full">
<para>How is it possible for a partition to be more than 100%
full?</para>
</question>
<answer>
<para>A portion of each UFS partition (8%, by default) is
reserved for use by the operating system and the
<username>root</username> user.
&man.df.1; does not count that space when
calculating the <literal>Capacity</literal> column, so it can
exceed 100%. Also, you will notice that the
<literal>Blocks</literal> column is always greater than the
sum of the <literal>Used</literal> and
<literal>Avail</literal> columns, usually by a factor of
8%.</para>
<para>For more details, look up the <option>-m</option> option
in &man.tunefs.8;.</para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter id="admin">
<title>System Administration</title>
<qandaset>
<qandaentry>
<question id="startup-config-files">
<para>Where are the system start-up configuration files?</para>
</question>
<answer>
<para>The primary configuration file is
<filename>/etc/defaults/rc.conf</filename> (see
&man.rc.conf.5;) System startup scripts such as
<filename>/etc/rc</filename> and
<filename>/etc/rc.d</filename> (see &man.rc.8;) just
include this file. <emphasis>Do not edit this
file!</emphasis> Instead, if there is any entry in
<filename>/etc/defaults/rc.conf</filename> that you want
to change, you should copy the line into
<filename>/etc/rc.conf</filename> and change it
there.</para>
<para>For example, if you wish to start named, the included
DNS server, all you need to do is:</para>
<screen>&prompt.root; <userinput>echo named_enable="YES" &gt;&gt; /etc/rc.conf</userinput></screen>
<para>To start up local services, place shell scripts in the
<filename>/usr/local/etc/rc.d</filename> directory. These
shell scripts should be set executable, and end with a
.sh.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="adding-users">
<para>How do I add a user easily?</para>
</question>
<answer>
<para>Use the &man.adduser.8; command, or the &man.pw.8;
command for more complicated situations.</para>
<para>To remove the user, use the &man.rmuser.8; command or,
if necessary, &man.pw.8;.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="root-not-found-cron-errors">
<para>Why do I keep getting messages like <errorname>root: not
found</errorname> after editing my crontab file?</para>
</question>
<answer>
<para>This is normally caused by editing the system crontab
(<filename>/etc/crontab</filename>) and then using
&man.crontab.1; to install it:</para>
<screen>&prompt.root; <userinput>crontab /etc/crontab</userinput></screen>
<para>This is not the correct way to do things. The system
crontab has a different format to the per-user crontabs
which &man.crontab.1; updates (the &man.crontab.5; manual
page explains the differences in more detail).</para>
<para>If this is what you did, the extra crontab is simply a
copy of <filename>/etc/crontab</filename> in the wrong
format it. Delete it with the command:</para>
<screen>&prompt.root; <userinput>crontab -r</userinput></screen>
<para>Next time, when you edit
<filename>/etc/crontab</filename>, you should not do
anything to inform &man.cron.8; of the changes, since it
will notice them automatically.</para>
<para>If you want something to be run once per day, week, or
month, it is probably better to add shell scripts
<filename>/usr/local/etc/periodic</filename>, and let the
&man.periodic.8; command run from the system cron schedule
it with the other periodic system tasks.</para>
<para>The actual reason for the error is that the system
crontab has an extra field, specifying which user to run the
command as. In the default system crontab provided with
FreeBSD, this is <username>root</username> for all entries.
When this crontab is used as the <username>root</username>
user's crontab (which is <emphasis>not</emphasis> the
same as the system crontab), &man.cron.8; assumes the string
<literal>root</literal> is the first word of the command to
execute, but no such command exists.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="su-wheel-group">
<para>Why do I get the error, <errorname>you are not in the correct
group to su root</errorname> when I try to su to
<username>root</username>?</para>
</question>
<answer>
<para>This is a security feature. In order to su to
<username>root</username> (or any other account with superuser
privileges), you must be in the <groupname>wheel</groupname>
group. If this feature were not there, anybody with an account
on a system who also found out <username>root</username>'s
password would be able to gain superuser level access to the
system. With this feature, this is not strictly true;
&man.su.1; will prevent them from even trying to enter the
password if they are not in <groupname>wheel</groupname>.</para>
<para>To allow someone to su to <username>root</username>, simply
put them in the <groupname>wheel</groupname> group.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="rcconf-readonly">
<para>I made a mistake in <filename>rc.conf</filename>,
or another startup file, and
now I cannot edit it because the filesystem is read-only.
What should I do?</para>
</question>
<answer>
<para>When you get the prompt to enter the shell
pathname, simply press <literal>ENTER</literal>, and run
<command>mount /</command> to re-mount the root filesystem in
read/write mode. You may also need to run <command>mount -a -t
ufs</command> to mount the filesystem where your favorite
editor is defined. If your favorite editor is on a network
filesystem, you will need to either configure the network
manually before you can mount network filesystems, or use an
editor which resides on a local filesystem, such as
&man.ed.1;.</para>
<para>If you intend to use a full screen editor such
as &man.vi.1; or &man.emacs.1;, you may also need to
run <command>export TERM=cons25</command> so that these
editors can load the correct data from the &man.termcap.5;
database.</para>
<para>Once you have performed these steps, you can edit
<filename>/etc/rc.conf</filename> as you usually would
to fix the syntax error. The error message displayed
immediately after the kernel boot messages should tell you
the number of the line in the file which is at fault.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="printer-setup">
<para>Why am I having trouble setting up my printer?</para>
</question>
<answer>
<para>Please have a look at the Handbook entry on printing. It
should cover most of your problem. See the <ulink
url="&url.books.handbook;/printing.html">
Handbook entry on printing</ulink>.</para>
<para>Some printers require a host-based driver to do any
kind of printing. These so-called
<quote>WinPrinters</quote> are not natively supported by
FreeBSD. If your printer does not work in DOS or &windowsnt;
4.0, it is probably a WinPrinter. Your only hope of
getting one of these to work is to check if the <filename
role="package">print/pnm2ppa</filename> port supports
it.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="keyboard-mappings">
<para>How can I correct the keyboard mappings for my system?</para>
</question>
<answer>
<para>Please see the Handbook section on <ulink
url="&url.books.handbook;/using-localization.html">using
localization</ulink>, specifically the section on <ulink
url="&url.books.handbook;/using-localization.html#SETTING-CONSOLE">console
setup</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="pnp-resources">
<para>Why do I get messages like: <errorname>unknown: &lt;PNP0303&gt;
can't assign resources</errorname> on boot?</para>
</question>
<answer>
<para>The following is an excerpt from a post to the
freebsd-current mailing list.</para>
<blockquote>
<attribution>&a.wollman;, 24 April 2001</attribution>
<para>The <quote>can't assign resources</quote> messages
indicate that the devices are legacy ISA devices for which a
non-PnP-aware driver is compiled into the kernel. These
include devices such as keyboard controllers, the
programmable interrupt controller chip, and several other
bits of standard infrastructure. The resources cannot be
assigned because there is already a driver using those
addresses.</para>
</blockquote>
</answer>
</qandaentry>
<qandaentry>
<question id="user-quotas">
<para>Why can I not get user quotas to work properly?</para>
</question>
<answer>
<!-- XXX
This may be the worst answer in the entire document.
-->
<orderedlist>
<listitem>
<para>Do not turn on quotas on <filename>/</filename>.</para>
</listitem>
<listitem>
<para>Put the quota file on the filesystem that the quotas
are to be enforced on, i.e.:</para>
<informaltable frame="none" pgwide="1">
<tgroup cols="2">
<thead>
<row>
<entry>Filesystem</entry>
<entry>Quota file</entry>
</row>
</thead>
<tbody>
<row>
<entry><filename>/usr</filename></entry>
<entry><filename>/usr/admin/quotas</filename></entry>
</row>
<row>
<entry><filename>/home</filename></entry>
<entry><filename>/home/admin/quotas</filename></entry>
</row>
<row>
<entry>&hellip;</entry>
<entry>&hellip;</entry>
</row>
</tbody>
</tgroup>
</informaltable>
</listitem>
</orderedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="sysv-ipc">
<para>Does FreeBSD support System V IPC primitives?</para>
</question>
<answer>
<para>Yes, FreeBSD supports System V-style IPC, including
shared memory, messages and semaphores, in the GENERIC
kernel. In a custom kernel, enable this support by adding
the following lines to your kernel config.</para>
<programlisting>options SYSVSHM # enable shared memory
options SYSVSEM # enable for semaphores
options SYSVMSG # enable for messaging</programlisting>
<para>Recompile and install your kernel.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="sendmail-alternative">
<para>What other mail-server software can I use instead of
Sendmail?</para>
</question>
<answer>
<para><ulink url="http://www.sendmail.org/">Sendmail</ulink> is
the default mail-server software for FreeBSD, but you can
easily replace it with one of the other MTA (for instance,
an MTA installed from the ports).</para>
<para>There are various alternative MTAs in the ports tree
already, with <filename
role="package">mail/exim</filename>, <filename
role="package">mail/postfix</filename>, <filename
role="package">mail/qmail</filename>, and <filename
role="package">mail/zmailer</filename> being some of the
most popular choices.</para>
<para>Diversity is nice, and the fact that you have many
different mail-servers to chose from is considered a
good thing; therefore try to avoid
asking questions like <quote>Is Sendmail better than
Qmail?</quote> in the mailing lists. If you do feel like
asking, first check the mailing list archives. The
advantages and disadvantages of each and every one of the
available MTAs have already been discussed a few
times.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="forgot-root-pw">
<para>I have forgotten the <username>root</username> password! What
do I do?</para>
</question><answer>
<para>Do not panic! Restart the system, type
<userinput>boot -s</userinput> at the Boot: prompt to
enter Single User mode. At the question about the shell to
use, hit ENTER. You will be dropped to a &prompt.root;
prompt. Enter <command>mount -u /</command> to remount
your root filesystem read/write, then run <command>mount
-a</command> to remount all the filesystems. Run
<command>passwd root</command> to change the
<username>root</username> password then run &man.exit.1;
to continue booting.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="CAD-reboot">
<para>How do I keep <keycombo
action="simul"><keycap>Control</keycap><keycap>Alt</keycap><keycap>Delete</keycap></keycombo>
from rebooting the system?</para>
</question>
<answer>
<para>If you are using syscons (the default console driver)
build and install a new kernel with the
line</para>
<programlisting>options SC_DISABLE_REBOOT</programlisting>
<para>in the configuration file. If you use the PCVT console
driver, use the following kernel configuration line
instead.</para>
<programlisting>options PCVT_CTRL_ALT_DEL</programlisting>
</answer>
</qandaentry>
<qandaentry>
<question id="dos-to-unix-txt">
<para>How do I reformat DOS text files to &unix; ones?</para>
</question>
<answer>
<para>Use this perl command:</para>
<screen>&prompt.user; <userinput>perl -i.bak -npe 's/\r\n/\n/g' file ...</userinput></screen>
<para>file is the file(s) to process. The modification is done
in-place, with the original file stored with a .bak
extension.</para>
<para>Alternatively you can use the
&man.tr.1;
command:</para>
<screen>&prompt.user; <userinput>tr -d '\r' &lt; <replaceable>dos-text-file</replaceable> &gt; <replaceable>unix-file</replaceable></userinput></screen>
<para><replaceable>dos-text-file</replaceable> is the file
containing DOS text while <replaceable>unix-file</replaceable>
will contain the converted output. This can be quite a bit
faster than using perl.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="kill-by-name">
<para>How do I kill processes by name?</para>
</question><answer>
<para>Use &man.killall.1;.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="root-acl">
<para>Why is su bugging me about not being in
<username>root</username>'s ACL?</para>
</question>
<answer>
<para>The error comes from the Kerberos distributed
authentication system. The problem is not fatal but annoying.
You can either run su with the -K option, or uninstall
Kerberos as described in the next question.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="uninstall-kerberos">
<para>How do I uninstall Kerberos?</para>
</question>
<answer>
<para>To remove Kerberos from the system, reinstall the bin
distribution for the release you are running. If you have
the CDROM, you can mount the cd (we will assume on /cdrom)
and run</para>
<screen>&prompt.root; <userinput>cd /cdrom/bin</userinput>
&prompt.root; <userinput>./install.sh</userinput></screen>
<para>Alternately, you can remove all
<makevar>MAKE_KERBEROS</makevar> options from
<filename>/etc/make.conf</filename> and rebuild
world.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="where-is-makedev">
<para>What happened to
<filename>/dev/MAKEDEV</filename>?</para>
</question>
<answer>
<para>FreeBSD 5.X and beyond use the &man.devfs.8; device-on-demand
system. Device drivers automatically create new device
nodes as they are needed, obsoleting
<filename>/dev/MAKEDEV</filename>.</para>
<para>If you are running FreeBSD 4.X or earlier and
<filename>/dev/MAKEDEV</filename> is missing, then you
really do have a problem. Grab a copy from the system
source code, probably in
<filename>/usr/src/etc/MAKEDEV</filename>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="add-pty">
<para>How do I add pseudoterminals to the system?</para>
</question>
<answer>
<para>If you have lots of telnet, ssh, X, or screen users,
you will probably run out of pseudoterminals. Here is how to
add more:</para>
<procedure>
<step>
<para>Build and install a new kernel with the line</para>
<programlisting>pseudo-device pty 256</programlisting>
<para>in the configuration file.</para>
</step>
<step>
<para>Run the commands</para>
<screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>sh MAKEDEV pty{1,2,3,4,5,6,7}</userinput></screen>
<para>to make 256 device nodes for the new terminals.</para>
</step>
<step>
<para>Edit <filename>/etc/ttys</filename> and add lines
for each of the 256 terminals. They should match the form
of the existing entries, i.e. they look like</para>
<programlisting>ttyqc none network</programlisting>
<para>The order of the letter designations is
<literal>tty[pqrsPQRS][0-9a-v]</literal>, using a
regular expression. </para>
</step>
<step>
<para>Reboot the system with the new kernel and you are
ready to go.</para>
</step>
</procedure>
</answer>
</qandaentry>
<qandaentry>
<question id="create-snd0">
<para>Why can I not create the snd0 device?</para>
</question>
<answer>
<para>There is no <devicename>snd</devicename> device. The name
is used as a shorthand for the various devices that make up the
FreeBSD sound driver, such as <devicename>mixer</devicename>,
<devicename>sequencer</devicename>, and
<devicename>dsp</devicename>.</para>
<para>To create these devices you should</para>
<screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>sh MAKEDEV snd0</userinput></screen>
<note>
<para>You can omit this step if you are running FreeBSD
5.0-RELEASE or newer with &man.devfs.5;
enabled.</para>
</note>
</answer>
</qandaentry>
<qandaentry>
<question id="reread-rc">
<para>How do I re-read <filename>/etc/rc.conf</filename> and
re-start <filename>/etc/rc</filename> without a
reboot?</para>
</question>
<answer>
<para>Go into single user mode and then back to multi user
mode.</para>
<para>On the console do:</para>
<screen>&prompt.root; <userinput>shutdown now</userinput>
(Note: without -r or -h)
&prompt.root; <userinput>return</userinput>
&prompt.root; <userinput>exit</userinput></screen>
</answer>
</qandaentry>
<qandaentry>
<question id="release-candidate">
<para>I tried to update my system to the latest -STABLE, but
got -BETAx, -RC or -PRERELEASE! What is going on?</para>
</question>
<answer>
<para>Short answer: it is just a name. RC stands for
<quote>Release Candidate</quote>. It signifies that a
release is imminent. In FreeBSD, -PRERELEASE is typically
synonymous with the code freeze before a release. (For
some releases, the -BETA label was used in the same way as
-PRERELEASE.)</para>
<para>Long answer: FreeBSD derives its releases from one of
two places. Major, dot-zero, releases, such as
4.0-RELEASE and 5.0-RELEASE, are branched from the head of
the development stream, commonly referred to as <link
linkend="current">-CURRENT</link>. Minor releases, such
as 4.1-RELEASE or 5.2-RELEASE, have been snapshots of the
active <link linkend="stable">-STABLE</link> branch.
Starting with 4.3-RELEASE, each release also now has its
own branch which can be tracked by people requiring an
extremely conservative rate of development (typically only
security advisories).</para>
<para>When a release is about to be made, the branch from
which it will be derived from has to undergo a certain
process. Part of this process is a code freeze. When a
code freeze is initiated, the name of the branch is
changed to reflect that it is about to become a release.
For example, if the branch used to be called 4.5-STABLE,
its name will be changed to 4.6-PRERELEASE to signify the
code freeze and signify that extra pre-release testing
should be happening. Bug fixes can still be committed to
be part of the release. When the source code is in shape
for the release the name will be changed to 4.6-RC to
signify that a release is about to be made from it. Once
in the RC stage, only the most critical bugs found can be
fixed. Once the release (4.6-RELEASE in this example) and
release branch have been made, the branch will be renamed
to 4.6-STABLE.</para>
<para>For more information on version numbers and the
various CVS branches, refer to the
<ulink url="&url.articles.releng;/article.html">Release
Engineering</ulink> article.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="kernel-chflag-failure">
<para>I tried to install a new kernel, and the chflags
failed. How do I get around this?</para>
</question>
<answer>
<para>Short answer: You are probably at security level
greater than 0. Reboot directly to single user mode to
install the kernel.</para>
<para>Long answer: FreeBSD disallows changing system flags
at security levels greater than 0. You can check your
security level with the command:</para>
<screen>&prompt.root; <userinput>sysctl kern.securelevel</userinput></screen>
<para>You cannot lower the security level; you have to boot to
single mode to install the kernel, or change the security
level in <filename>/etc/rc.conf</filename> then reboot. See
the &man.init.8; manual page for details on securelevel, and see
<filename>/etc/defaults/rc.conf</filename> and the
&man.rc.conf.5; manual page for more information on
rc.conf.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="kernel-securelevel-time">
<para>I cannot change the time on my system by more than one second!
How do I get around this?</para>
</question>
<answer>
<para>Short answer: You are probably at security level
greater than 1. Reboot directly to single user mode to
change the date.</para>
<para>Long answer: FreeBSD disallows changing the time by
more that one second at security levels greater than 1. You
can check your security level with the command:</para>
<screen>&prompt.root; <userinput>sysctl kern.securelevel</userinput></screen>
<para>You cannot lower the security level; you have to boot
to single mode to change the date, or change the security
level in <filename>/etc/rc.conf</filename> then
reboot. See the &man.init.8; manual page for details on
securelevel, and see
<filename>/etc/defaults/rc.conf</filename> and the
&man.rc.conf.5; manual page for more information on
rc.conf.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="statd-mem-leak">
<para>Why is <command>rpc.statd</command> using 256 megabytes of
memory?</para>
</question>
<answer>
<para>No, there is no memory leak, and it is not using 256 Mbytes
of memory. For convenience, <command>rpc.statd</command> maps an
obscene amount of memory into its address space.
There is nothing terribly wrong with this from a technical
standpoint; it just throws off things like &man.top.1; and
&man.ps.1;.</para>
<para>&man.rpc.statd.8; maps its status file (resident on
<filename>/var</filename>) into its address space; to save
worrying about remapping it later when it needs to grow, it maps
it with a generous size. This is very evident from the source
code, where one can see that the length argument to &man.mmap.2;
is <literal>0x10000000</literal>, or one sixteenth of the
address space on an IA32, or exactly 256MB.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="unsetting-schg">
<para>Why can I not unset the <literal>schg</literal> file
flag?</para>
</question>
<answer>
<para>You are running at an elevated (i.e., greater than 0)
securelevel. Lower the securelevel and try again. For more
information, see <link linkend="securelevel">the FAQ entry on
securelevel</link> and the &man.init.8; manual page.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ssh-shosts">
<para>Why does SSH authentication through
<filename>.shosts</filename> not work by default in recent
versions of FreeBSD?</para>
</question>
<answer>
<para>The reason why <filename>.shosts</filename>
authentication does not work by default in more recent
versions of FreeBSD is because &man.ssh.1;
is not installed suid <username>root</username> by default. To
<quote>fix</quote> this, you can do one of the
following:</para>
<itemizedlist>
<listitem>
<para>As a permanent fix, set
<makevar>ENABLE_SUID_SSH</makevar> to <literal>true</literal>
in <filename>/etc/make.conf</filename> and rebuild ssh
(or run <command>make world</command>).</para>
</listitem>
<listitem>
<para>As a temporary fix, change the mode on
<filename>/usr/bin/ssh</filename> to <literal>4555</literal>
by running <command>chmod 4555 /usr/bin/ssh</command> as
<username>root</username>. Then add
<makevar>ENABLE_SUID_SSH= true</makevar> to
<filename>/etc/make.conf</filename> so the change takes
effect the next time <command>make world</command> is
run.</para>
</listitem>
</itemizedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="vnlru">
<para>What is <literal>vnlru</literal>?</para>
</question>
<answer>
<para><literal>vnlru</literal> flushes and frees vnodes when
the system hits the <varname>kern.maxvnodes</varname>
limit. This kernel thread sits mostly idle, and only
activates if you have a huge amount of RAM and are
accessing tens of thousands of tiny files.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="top-memory-states">
<para>What do the various memory states displayed by
<command>top</command> mean?</para>
</question>
<!-- Provided by John Dyson via Usenet -->
<answer>
<itemizedlist>
<listitem><para><literal>Active</literal>: pages recently
statistically used.</para></listitem>
<listitem><para><literal>Inactive</literal>: pages
recently statistically unused.</para></listitem>
<listitem><para><literal>Cache</literal>: (most often)
pages that have percolated from inactive to a status
where they maintain their data, but can often be
immediately reused (either with their old association,
or reused with a new association.) There can be certain
immediate transitions from <literal>active</literal> to <literal>cache</literal> state if the
page is known to be clean (unmodified), but that
transition is a matter of policy, depending upon the
algorithm choice of the VM system
maintainer.</para></listitem>
<listitem><para><literal>Free</literal>: pages without
data content, and can be immediately used in certain
circumstances where cache pages might be ineligible.
Free pages can be reused at interrupt or process
state.</para></listitem>
<listitem><para><literal>Wired</literal>: pages that are
fixed into memory, usually for kernel purposes, but also
sometimes for special use in
processes.</para></listitem>
</itemizedlist>
<para>Pages are most often written to disk (sort of a VM
sync) when they are in the inactive state, but active
pages can also be synced (but requires the
availability of certain CPU features.) This depends upon
the CPU tracking of the modified bit being available,
and in certain situations there can be an advantage for a
block of VM pages to be synced, whether they are active or
inactive. In most common cases, it is best to think of
the inactive queue to be a queue of relatively unused
pages that might or might not be in the process of being
written to disk. Cached pages are already synced, not
mapped, but available for immediate process use with their
old association or with a new association. Free pages are
available at interrupt level, but cached or free pages can
be used at process state for reuse. Cache pages are not
adequately locked to be available at interrupt
level.</para>
<para>There are some other flags (e.g., busy flag or busy
count) that might modify some of the rules that I
described.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="free-memory-amount">
<para>How much free memory is available?</para>
</question>
<!-- Provided by John Dyson via Usenet -->
<answer>
<para>There are a couple of kinds of <quote>free
memory</quote>. One kind is the amount of memory
immediately available without paging anything else out.
That is approximately the size of cache queue + size of
free queue (with a derating factor, depending upon system
tuning.) Another kind of <quote>free memory</quote> is
the total amount of <acronym>VM</acronym> space. That can
be complex, but is dependent upon the amount of swap space
and memory. Other kinds of <quote>free memory</quote>
descriptions are also possible, but it is relatively
useless to define these, but rather it is important to
make sure that the paging rate is kept low, and to avoid
running out of swap space.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="var-empty">
<para>What is <filename>/var/empty</filename>? I can not
delete it!</para>
</question>
<answer>
<para><filename>/var/empty</filename> is a directory that the
&man.sshd.8; program uses when performing privilege separation.
The <filename>/var/empty</filename> directory is empty, owned by
<username>root</username> and has the <literal>schg</literal>
flag set.</para>
<para>Although it is not recommended to delete this directory, to
do so you will need to unset the <literal>schg</literal> flag
first. See the &man.chflags.1; manual page for more information
(and bear in mind the answer to <link linkend="unsetting-schg">
the question on unsetting the schg flag</link>).
</para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter id="x">
<title>The X Window System and Virtual Consoles</title>
<qandaset>
<qandaentry>
<question id="whatis-X">
<para>What is the X Window System?</para>
</question>
<answer>
<para>The X Window System is the most widely available windowing system
capable of running on &unix; or &unix;&nbsp;like systems, including
&os;. <ulink url= "http://www.x.org">The X.Org
Foundation</ulink> administers the <ulink
url="http://www.x.org/X11_protocol.html">X protocol
standards</ulink>. The current release of the specification
is 11.6, so you will often see references shortened to
<literal>X11R6</literal> or even just <literal>X11</literal>.
</para>
<para>Many implementations are available for different
architectures and operating systems. An
implementation of the server-side code is properly known
as an <literal>X server</literal>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="which-X">
<para>Which X implementations are available for &os;?</para>
</question>
<answer>
<para>Historically, the default implementation of X on
&os; has been
&xfree86; which is maintained by
<ulink url="http://www.xfree86.org">The XFree86 Project,
Inc.</ulink> This software was installed by default on
&os; versions up until 4.10 and 5.2. Although &xorg;
itself maintained an implementation during that time
period, it was basically only provided as a reference
platform, as it had suffered greatly from bitrot over
the years.</para>
<para>However, early in 2004, some XFree86 developers left
that project
over issues including the pace of code changes, future
directions, and interpersonal conflicts, and are now contributing
code directly to &xorg; instead. At that time, &xorg; updated its
source tree to the last &xfree86; release before its subsequent
licensing change (<application>XFree86 version 4.3.99.903</application>), incorporated
many changes that had previously been maintained separately,
and has released that software as <application>X11R6.7.0</application>. A separate but
related project, <ulink url="http://www.freedesktop.org">
freedesktop.org</ulink> (or <literal>fd.o</literal> for short),
is working on rearchitecting the original &xfree86; code to
offload more work onto the graphics cards (with the goal of
increased performance) and make it more modular
(with the goal of increased maintainability, and thus faster
releases as well as easier configuration). &xorg; intends to
incorporate the freedesktop.org changes in its future releases.</para>
<para>As of July 2004, in &os.current;,
&xfree86; has been replaced with &xorg; as the default
implementation. The &xfree86; ports
(<filename role="package">x11/XFree86-4</filename> and
subports) remain in the ports collection and are still
the default for &os.stable;.</para>
<note>
<para>The above describes the default X implementation installed.
It is still possible to install either implementation by
following the instructions in the entry for 20040723 in
<filename>/usr/ports/UPDATING</filename>.</para>
</note>
<warning>
<para>It is not currently
possible to mix-and-match pieces of each implementation;
one must choose one or the other.</para>
</warning>
<note>
<para>The following paragraphs refer to the
&xfree86; implementation, but most should also be applicable
to the &xorg; implementation as well. While the default
configuration filename for the &xorg; implementation is
<filename>xorg.conf</filename>, it will search for
<filename>XF86Config</filename> if it cannot find it.</para>
</note>
</answer>
</qandaentry>
<qandaentry>
<question id="xorg-compatibility">
<para>Will my existing applications run with the &xorg; suite?</para>
</question>
<answer>
<para>The &xorg; software is written to the same X11R6 specification
that &xfree86; is, so basic applications should work
unchanged. A few lesser-used protocols have been deprecated
(<literal>XIE</literal>, <literal>PEX</literal>, and
<literal>lbxproxy</literal>), but in the first two cases, the
&os; port of &xfree86; did not support them either.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="xfree86-split">
<para>Why did the X projects split, anyway?</para>
</question>
<answer>
<para>The answer to this question is outside the scope of
this FAQ. Note that there are voluminous postings in various
mailing list archives on the Internet; please use your favorite
search engine to investigate the history instead of asking this
question on the &os; mailing lists. It may even be the case
that only the participants will ever know for certain.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="why-choose-xorg">
<para>Why did &os; choose to go with the &xorg; ports by default?</para>
</question>
<answer>
<para>The &xorg; developers claim that their goal is to release
more often and incorporate new features more quickly. If they
are able to do so, this will be very attractive. Also, their
software still uses the traditional X license, while &xfree86;
is now using their modified one.</para>
<note>
<para>This decision is still controversial. Only time will
tell which implementation proves technically superior. Each
&os; user should decide which they prefer.</para>
</note>
</answer>
</qandaentry>
<qandaentry>
<question id="running-X">
<para>I want to run X, how do I go about it?</para>
</question>
<answer>
<para>The easiest way is to simply specify that you want to
run X during the installation process.</para>
<para>If you would like to add X to an existing installation, you
should use the <filename role="package">x11/xorg</filename>
meta-port, which will build and install all the necessary
components.</para>
<para>Then read and follow the documentation on the
&man.xorgconfig.1; tool, which assists you in
configuring &xfree86; for your particular graphics
card/mouse/etc. You may also wish to examine the
&man.xorgcfg.1; tool, which provides a graphical interface
to the X configuration process.</para>
<para>For further information, read the <ulink
url="&url.books.handbook;/x11.html">X11</ulink> section of the
FreeBSD Handbook.</para>
<para>You may also wish to investigate the Xaccel server.
See the section on <link linkend="xig">Xi Graphics</link> or
<link linkend="metrox">Metro Link</link> for more details.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="running-X-securelevels">
<para>I <emphasis>tried</emphasis> to run X, but I get an
<errorname>KDENABIO failed (Operation not permitted)</errorname>
error when I type <command>startx</command>. What do I do
now?</para>
</question>
<answer>
<para>Your system is probably running at a raised securelevel.
It is not possible to start X at a raised securelevel because
X requires write access to <devicename>/dev/io</devicename>.
For more information, see at the &man.init.8; manual
page.</para>
<para>So the question is what else you should do instead,
and you basically have two choices: set your securelevel
back down to zero (usually from <filename>/etc/rc.conf</filename>),
or run &man.xdm.1; at boot time (before the securelevel is
raised).</para>
<para>See <xref linkend="xdm-boot"> for more information about
running &man.xdm.1; at boot time.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="x-and-moused">
<para>Why does my mouse not work with X?</para>
</question>
<answer>
<para>If you are using syscons (the default console driver),
you can configure FreeBSD to support a mouse pointer on each
virtual screen. In order to avoid conflicting with X, syscons
supports a virtual device called
<devicename>/dev/sysmouse</devicename>. All mouse events received
from the real mouse device are written to the sysmouse device
via moused. If you wish to use your mouse on one or more
virtual consoles, <emphasis>and</emphasis> use X, see
<xref linkend="moused" remap="another section"> and set up
moused.</para>
<para>Then edit <filename>/etc/XF86Config</filename> and make
sure you have the following lines.</para>
<programlisting>Section Pointer
Protocol "SysMouse"
Device "/dev/sysmouse"
.....</programlisting>
<para>The above example is for &xfree86; 3.3.2 or later, and
for &xorg; 6.7.0. For earlier versions, the
<emphasis>Protocol</emphasis> should be
<emphasis>MouseSystems</emphasis>.</para>
<para>Some people prefer to use
<devicename>/dev/mouse</devicename> under X. To make this
work, <devicename>/dev/mouse</devicename> should be linked
to <devicename>/dev/sysmouse</devicename> (see
&man.sysmouse.4;):</para>
<screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>rm -f mouse</userinput>
&prompt.root; <userinput>ln -s sysmouse mouse</userinput></screen>
</answer>
</qandaentry>
<qandaentry>
<question id="x-and-wheel">
<para>My mouse has a fancy wheel. Can I use it in X?</para>
</question>
<answer>
<para>Yes.</para>
<para>You need to tell X that you have a 5 button mouse.
To do this, simply add the lines
<literal>Buttons 5</literal> and
<literal>ZAxisMapping 4 5</literal> to the
<quote>InputDevice</quote> section of
<filename>/etc/XF86Config</filename>. For example, you
might have the following <quote>InputDevice</quote> section
in <filename>/etc/XF86Config</filename>.</para>
<example>
<title><quote>InputDevice</quote> Section for Wheeled Mouse
in &xfree86; and &xorg; configuration file</title>
<programlisting>Section "InputDevice"
Identifier "Mouse1"
Driver "mouse"
Option "Protocol" "auto"
Option "Device" "/dev/sysmouse"
Option "Buttons" "5"
Option "ZAxisMapping" "4 5"
EndSection</programlisting>
</example>
<example>
<title><quote>.emacs</quote> example for naive page
scrolling with Wheeled Mouse (optional)</title>
<programlisting>;; wheel mouse
(global-set-key [mouse-4] 'scroll-down)
(global-set-key [mouse-5] 'scroll-up)</programlisting>
</example>
</answer>
</qandaentry>
<qandaentry>
<question id="no-remote-x11">
<para>How do I use remote X displays?</para>
</question>
<answer>
<para>For security reasons, the default setting is to not allow a
machine to remotely open a window.</para>
<para>To enable this feature, simply start
<application>X</application> with the optional
<option>-listen_tcp</option> argument:</para>
<screen>&prompt.user; <userinput>startx
-listen_tcp</userinput></screen>
</answer>
</qandaentry>
<qandaentry>
<question id="window-menu-weird">
<para>Why do X Window menus and dialog boxes not work
right?</para>
</question>
<answer>
<para>Try turning off the <keycap>Num Lock</keycap> key.</para>
<para>If your <keycap>Num Lock</keycap> key is on by default
at boot-time, you may add the following line in the
<literal>Keyboard</literal> section of the
<filename>XF86Config</filename> file.</para>
<programlisting># Let the server do the NumLock processing. This should only be
# required when using pre-R6 clients
ServerNumLock</programlisting>
</answer>
</qandaentry>
<qandaentry>
<question id="virtual-console">
<para>What is a virtual console and how do I make more?</para>
</question>
<answer>
<para>Virtual consoles, put simply, enable you to have several
simultaneous sessions on the same machine without doing anything
complicated like setting up a network or running X.</para>
<para>When the system starts, it will display a login prompt on
the monitor after displaying all the boot messages. You can
then type in your login name and password and start working (or
playing!) on the first virtual console.</para>
<para>At some point, you will probably wish to start another
session, perhaps to look at documentation for a program
you are running or to read your mail while waiting for an
FTP transfer to finish. Just do <keycombo
action="simul"><keycap>Alt</keycap><keycap>F2</keycap></keycombo>
(hold down the <keycap>Alt</keycap> key and press the
<keycap>F2</keycap> key), and you will find a login prompt
waiting for you on the second <quote>virtual
console</quote>! When you want to go back to the original
session, do <keycombo
action="simul"><keycap>Alt</keycap><keycap>F1</keycap></keycombo>.</para>
<para>The default FreeBSD installation has eight virtual
consoles enabled. <keycombo
action="simul"><keycap>Alt</keycap><keycap>F1</keycap></keycombo>,
<keycombo
action="simul"><keycap>Alt</keycap><keycap>F2</keycap></keycombo>,
<keycombo
action="simul"><keycap>Alt</keycap><keycap>F3</keycap></keycombo>,
and so on will switch between these virtual
consoles.</para>
<para>To enable more of them, edit
<filename>/etc/ttys</filename> (see &man.ttys.5;)
and add entries for <devicename>ttyv4</devicename>
to <devicename>ttyvc</devicename> after the comment on
<quote>Virtual terminals</quote>:</para>
<programlisting># Edit the existing entry for ttyv3 in /etc/ttys and change
# "off" to "on".
ttyv3 "/usr/libexec/getty Pc" cons25 on secure
ttyv4 "/usr/libexec/getty Pc" cons25 on secure
ttyv5 "/usr/libexec/getty Pc" cons25 on secure
ttyv6 "/usr/libexec/getty Pc" cons25 on secure
ttyv7 "/usr/libexec/getty Pc" cons25 on secure
ttyv8 "/usr/libexec/getty Pc" cons25 on secure
ttyv9 "/usr/libexec/getty Pc" cons25 on secure
ttyva "/usr/libexec/getty Pc" cons25 on secure
ttyvb "/usr/libexec/getty Pc" cons25 on secure</programlisting>
<para>Use as many or as few as you want. The more virtual
terminals you have, the more resources that are used; this
can be important if you have 8MB RAM or less. You may also
want to change the <literal>secure</literal>
to <literal>insecure</literal>.</para>
<important>
<para>If you want to run an X server you
<emphasis>must</emphasis> leave at least one virtual
terminal unused (or turned off) for it to use. That is to
say that if you want to have a login prompt pop up for all
twelve of your Alt-function keys, you are out of luck - you
can only do this for eleven of them if you also want to run
an X server on the same machine.</para>
</important>
<para>The easiest way to disable a console is by turning it off.
For example, if you had the full 12 terminal allocation
mentioned above and you wanted to run X, you would change
settings for virtual terminal 12 from:</para>
<programlisting>ttyvb "/usr/libexec/getty Pc" cons25 on secure</programlisting>
<para>to:</para>
<programlisting>ttyvb "/usr/libexec/getty Pc" cons25 off secure</programlisting>
<para>If your keyboard has only ten function keys, you would
end up with:</para>
<programlisting>ttyv9 "/usr/libexec/getty Pc" cons25 off secure
ttyva "/usr/libexec/getty Pc" cons25 off secure
ttyvb "/usr/libexec/getty Pc" cons25 off secure</programlisting>
<para>(You could also just delete these lines.)</para>
<para>Once you have edited <filename>/etc/ttys</filename>,
the next step is to make sure that you have enough virtual
terminal devices. The easiest way to do this is:</para>
<screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>sh MAKEDEV vty12</userinput></screen>
<note>
<para>On FreeBSD 5.X and beyond you do not have to create devices
manually if you are using <literal>DEVFS</literal>,
since the proper device nodes will be automatically
created under <filename
class="directory">/dev</filename>.</para>
</note>
<para>Next, the easiest (and cleanest) way to activate the
virtual consoles is to reboot. However, if you really do not
want to reboot, you can just shut down the X Window system
and execute (as <username>root</username>):</para>
<screen>&prompt.root; <userinput>kill -HUP 1</userinput></screen>
<para>It is imperative that you completely shut down X Window if
it is running, before running this command. If you do not,
your system will probably appear to hang/lock up after
executing the kill command.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="vty-from-x">
<para>How do I access the virtual consoles from X?</para>
</question>
<answer>
<para>Use <keycombo action="simul">
<keycap>Ctrl</keycap>
<keycap>Alt</keycap>
<keycap>F<replaceable>n</replaceable></keycap>
</keycombo> to switch back to a virtual console.
<keycombo action="simul">
<keycap>Ctrl</keycap>
<keycap>Alt</keycap>
<keycap>F1</keycap>
</keycombo> would return you to the first virtual console.</para>
<para>Once you are back to a text console, you can then use
<keycombo action="simul">
<keycap>Alt</keycap>
<keycap>F<replaceable>n</replaceable></keycap>
</keycombo> as normal to move between them.</para>
<para>To return to the X session, you must switch to the
virtual console running X. If you invoked X from the
command line, (e.g., using <command>startx</command>) then
the X session will attach to the next unused virtual
console, not the text console from which it was invoked.
If you have eight active virtual terminals then X will be
running on the ninth, and you would use
<keycombo action="simul">
<keycap>Alt</keycap>
<keycap>F9</keycap>
</keycombo> to return.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="xdm-boot">
<para>How do I start XDM on boot?</para>
</question><answer>
<para>There are two schools of thought on how to start
&man.xdm.1;. One school starts xdm from
<filename>/etc/ttys</filename> (see &man.ttys.5;) using
the supplied example, while the other simply runs xdm from
<filename>rc.local</filename> (see &man.rc.8;) or from a
<filename>X.sh</filename> script in
<filename>/usr/local/etc/rc.d</filename>. Both are equally
valid, and one may work in situations where the other does
not. In both cases the result is the same: X will pop up
a graphical login: prompt.</para>
<para>The ttys method has the advantage of documenting which
vty X will start on and passing the responsibility of
restarting the X server on logout to init. The rc.local
method makes it easy to kill xdm if there is a problem
starting the X server.</para>
<para>If loaded from rc.local, <command>xdm</command> should
be started without any arguments (i.e., as a daemon). xdm must
start AFTER getty runs, or else getty and xdm will conflict,
locking out the console. The best way around this is to have
the script sleep 10 seconds or so then launch xdm.</para>
<para>If you are to start <command>xdm</command> from
<filename>/etc/ttys</filename>, there still is a chance of
conflict between <command>xdm</command> and
&man.getty.8;. One way to avoid this is to add the
<literal>vt</literal> number in the
<filename>/usr/X11R6/lib/X11/xdm/Xservers</filename>
file.</para>
<programlisting>:0 local /usr/X11R6/bin/X vt4</programlisting>
<para>The above example will direct the X server to run in
<devicename>/dev/ttyv3</devicename>. Note the number is offset by
one. The X server counts the vty from one, whereas the FreeBSD
kernel numbers the vty from zero.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="xconsole-failure">
<para>Why do I get <errorname>Couldn't open console</errorname>
when I run xconsole?</para>
</question>
<answer>
<para>If you start <application>X</application>
with
<command>startx</command>, the permissions on
<devicename>/dev/console</devicename> will
<emphasis>not</emphasis> get changed, resulting in
things like
<command>xterm -C</command> and
<command>xconsole</command> not working.</para>
<para>This is because of the way console permissions are set
by default. On a multi-user system, one does not necessarily
want just any user to be able to write on the system console.
For users who are logging directly onto a machine with a VTY,
the &man.fbtab.5;
file exists to solve such problems.</para>
<para>In a nutshell, make sure an uncommented line of the
form</para>
<programlisting>/dev/ttyv0 0600 /dev/console</programlisting>
<para>is in <filename>/etc/fbtab</filename> (see
&man.fbtab.5;) and it will ensure that whomever logs in on
<devicename>/dev/ttyv0</devicename> will own the
console.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="xfree86-root">
<para>Before, I was able to run &xfree86; as a regular user. Why does
it now say that I must be <username>root</username>?</para>
</question>
<answer>
<para>All X servers need to be run as
<username>root</username> in order to get direct access to
your video hardware. Older versions of &xfree86; (&lt;=
3.3.6) installed all bundled servers to be automatically
run as <username>root</username> (setuid to
<username>root</username>). This is obviously a security
hazard because X servers are large, complicated programs.
Newer versions of &xfree86; do not install the servers
setuid to <username>root</username> for just this
reason.</para>
<para>Obviously, running an X server as the
<username>root</username> user is not acceptable, nor a
good idea security-wise. There are two ways to be able to
use X as a regular user. The first is to use
<command>xdm</command> or another display manager (e.g.,
<command>kdm</command>); the second is to use the
<command>Xwrapper</command>.</para>
<para><command>xdm</command> is a daemon that handles graphical
logins. It is usually started at boot time, and is responsible
for authenticating users and starting their sessions; it is
essentially the graphical counterpart of
&man.getty.8; and &man.login.1;. For
more information on <command>xdm</command> see
<ulink url="http://www.xfree86.org/support.html">the &xfree86;
documentation</ulink>, and the <link linkend="xdm-boot">the FAQ
entry</link> on it.</para>
<para><command>Xwrapper</command> is the X server wrapper; it is
a small utility to enable one to manually run an X server while
maintaining reasonable safety. It performs some sanity checks
on the command line arguments given, and if they pass, runs the
appropriate X server. If you do not want to run a display
manger for whatever reason, this is for you. If you have
installed the complete ports collection, you can find the port in
<filename>/usr/ports/x11/wrapper</filename>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ps2-x">
<para>Why does my PS/2 mouse misbehave under X?</para>
</question>
<answer>
<para>Your mouse and the mouse driver may have somewhat become
out of synchronization.</para>
<para>
In rare cases the driver may erroneously report
synchronization problem and you may see the kernel
message:</para>
<programlisting>psmintr: out of sync (xxxx != yyyy)</programlisting>
<para>and notice that your mouse does not work properly.</para>
<para>If this happens, disable the synchronization check code
by setting the driver flags for the PS/2 mouse driver to 0x100.
Enter <emphasis>UserConfig</emphasis> by giving the
<option>-c</option> option at the boot prompt:</para>
<screen>boot: <userinput>-c</userinput></screen>
<para>Then, in the <emphasis>UserConfig</emphasis> command
line, type:</para>
<screen>UserConfig&gt; <userinput>flags psm0 0x100</userinput>
UserConfig&gt; <userinput>quit</userinput></screen>
</answer>
</qandaentry>
<qandaentry>
<question id="ps2-mousesystems">
<para>Why does my PS/2 mouse from MouseSystems not
work?</para>
</question>
<answer>
<para>There have been some reports that certain model of PS/2
mouse from MouseSystems works only if it is put into the
<quote>high resolution</quote> mode. Otherwise, the mouse
cursor may jump to the upper-left corner of the screen every
so often.</para>
<para>Specify the flags 0x04 to the PS/2 mouse driver to put
the mouse into the high resolution mode. Enter
<emphasis>UserConfig</emphasis> by giving the
<option>-c</option> option at the boot prompt:</para>
<screen>boot: <userinput>-c</userinput></screen>
<para>Then, in the <emphasis>UserConfig</emphasis> command line,
type:</para>
<screen>UserConfig&gt; <userinput>flags psm0 0x04</userinput>
UserConfig&gt; <userinput>quit</userinput></screen>
<para>See the previous section for another possible cause of mouse
problems.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="imake-tmpl">
<para>When building an X app, <command>imake</command> cannot
find <filename>Imake.tmpl</filename>. Where is it?</para>
</question>
<answer>
<para><filename>Imake.tmpl</filename> is part of the Imake
package, a standard X application building tool.
<filename>Imake.tmpl</filename>, as well as several header
files that are required to build X apps, is contained in
the X prog distribution. You can install this from
sysinstall or manually from the X distribution
files.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="xfree86-version">
<para>I want to install different X server.</para>
</question>
<answer>
<para>&os; versions prior 5.3 will use the default
<application>&xfree86;&nbsp;4.X</application>,
while latter versions will default to
<application>&xorg;</application>.
If you want to run a different X11 implementation
than the default one, add the following line to
<filename>/etc/make.conf</filename>, (if you
do not have this file, create it):</para>
<programlisting>X_WINDOW_SYSTEM= xorg</programlisting>
<para>This variable may be set to <literal>xorg</literal>,
<literal>xfree86-4</literal>, or
<literal>xfree86-3</literal>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="mouse-button-reverse">
<para>How do I reverse the mouse buttons?</para>
</question>
<answer>
<para>Run the command
<command>xmodmap -e "pointer = 3 2 1"</command> from your
<filename>.xinitrc</filename> or <filename>.xsession</filename>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="install-splash">
<para>How do I install a splash screen and where do I find
them?</para>
</question>
<answer>
<para>&os; have a feature to allow the display of
<quote>splash</quote> screens during the boot
messages. The splash screens currently must be a 256 color
bitmap (<filename>*.BMP</filename>) or ZSoft PCX
(<filename>*.PCX</filename>) file. In addition, they must
have a resolution of 320x200 or less to work on standard
VGA adapters. If you compile VESA support into your
kernel, then you can use larger bitmaps up to 1024x768.
The actual VESA support can either be compiled directly
into the kernel with the <literal>VESA</literal> kernel
config option or by loading the VESA kld module during
bootup.</para>
<para>To use a splash screen, you need to modify the startup
files that control the boot process for &os;.</para>
<para>You need to create
a <filename>/boot/loader.rc</filename> file that contains
the following lines:</para>
<programlisting>include /boot/loader.4th
start</programlisting>
<para>and a <filename>/boot/loader.conf</filename> that
contains the following:</para>
<programlisting>splash_bmp_load="YES"
bitmap_load="YES"</programlisting>
<para>This assumes you are using
<filename>/boot/splash.bmp</filename> for your splash
screen. If you would rather use a PCX file, copy it to
<filename>/boot/splash.pcx</filename>, create a
<filename>/boot/loader.rc</filename> as instructed above,
and create a <filename>/boot/loader.conf</filename> that
contains:</para>
<programlisting>splash_pcx_load="YES"
bitmap_load="YES"
bitmap_name="/boot/splash.pcx"</programlisting>
<para>Now all you need is a splash screen. For that you can
surf on over to the gallery at
<ulink url="http://www.baldwin.cx/splash/"></ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="windows-keys">
<para>Can I use the &windows;
keys on my keyboard in X?</para>
</question>
<answer>
<para>Yes. All you need to do is use &man.xmodmap.1; to define
what function you wish them to perform.</para>
<para>Assuming all <quote>&windows;</quote> keyboards
are standard then the keycodes for the 3 keys are</para>
<itemizedlist>
<listitem>
<para>115 - &windows; key, between
the left-hand Ctrl and Alt keys</para>
</listitem>
<listitem>
<para>116 - &windows; key, to the
right of the <keycap>AltGr</keycap> key</para>
</listitem>
<listitem>
<para>117 - <keycap>Menu</keycap> key, to the left of
the right-hand <keycap>Ctrl</keycap> key</para>
</listitem>
</itemizedlist>
<para>To have the left &windows; key print a comma,
try this.</para>
<screen>&prompt.root; <userinput>xmodmap -e "keycode 115 = comma"</userinput></screen>
<para>You will probably have to re-start your window manager
to see the result.</para>
<para>To have the &windows;
key-mappings enabled automatically every time you start X either
put the <command>xmodmap</command> commands in your
<filename>~/.xinitrc</filename> file or, preferably, create a file
<filename>~/.xmodmaprc</filename> and include the
<command>xmodmap</command> options, one per line, then add the
line</para>
<programlisting>xmodmap $HOME/.xmodmaprc</programlisting>
<para>to your <filename>~/.xinitrc</filename>.</para>
<para>For example, you could map the 3 keys to be
<keycap>F13</keycap>, <keycap>F14</keycap>, and
<keycap>F15</keycap>, respectively. This would make it
easy to map them to useful functions within applications
or your window manager, as demonstrated further
down.</para>
<para>To do this put the following in
<filename>~/.xmodmaprc</filename>.</para>
<programlisting>keycode 115 = F13
keycode 116 = F14
keycode 117 = F15</programlisting>
<para>If you use <command>fvwm2</command>, for example, you
could map the keys so that <keycap>F13</keycap> iconifies
(or de-iconifies) the window the cursor is in,
<keycap>F14</keycap> brings the window the cursor is in to
the front or, if it is already at the front, pushes it to
the back, and <keycap>F15</keycap> pops up the main
Workplace (application) menu even if the cursor is not on
the desktop, which is useful if you do not have any part
of the desktop visible (and the logo on the key matches
its functionality).</para>
<para>The following entries in
<filename>~/.fvwmrc</filename> implement the
aforementioned setup:</para>
<programlisting>Key F13 FTIWS A Iconify
Key F14 FTIWS A RaiseLower
Key F15 A A Menu Workplace Nop</programlisting>
</answer>
</qandaentry>
<qandaentry>
<question id="x-3d-acceleration">
<para>How can I get 3D hardware acceleration for
&opengl;?</para>
</question>
<answer>
<para>The availability of 3D acceleration depends on the
version of &xfree86; or &xorg; that you are using and the type of video chip
you have. If you have an NVIDIA chip, you can use the binary
drivers provided for FreeBSD on the
<ulink url="http://www.nvidia.com/content/drivers/drivers.asp">
Drivers</ulink> section of their website. For other cards
with &xfree86;-4 or &xorg;, including the Matrox G200/G400, ATI Rage
128/Radeon, and 3dfx Voodoo 3, 4, 5, and Banshee,
information on hardware acceleration is available on the
<ulink
url="http://people.FreeBSD.org/~anholt/dri/">XFree86-4
Direct Rendering on FreeBSD</ulink> page. Users of
&xfree86; version 3.3 can use the Utah-GLX port found in
<filename role="package">graphics/utah-glx</filename> to
get limited accelerated &opengl; on the Matrox Gx00, ATI
Rage Pro, SiS 6326, i810, Savage, and older NVIDIA
chips.</para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter id="networking">
<title>Networking</title>
<qandaset>
<qandaentry>
<question id="diskless-booting">
<para>Where can I get information on
<quote>diskless booting</quote>?</para>
</question>
<answer>
<para><quote>Diskless booting</quote> means that the FreeBSD
box is booted over a network, and reads the necessary files
from a server instead of its hard disk. For full details,
please read <ulink url="&url.books.handbook;/diskless.html">the
Handbook entry on diskless booting</ulink></para>
</answer>
</qandaentry>
<qandaentry>
<question id="router">
<para>Can a FreeBSD box be used as a dedicated network
router?</para>
</question>
<answer>
<para>Yes. Please see the Handbook entry on <ulink
url="&url.books.handbook;/advanced-networking.html"> advanced
networking</ulink>, specifically the section on <ulink
url="&url.books.handbook;/network-routing.html">routing
and gateways</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="win95-connection">
<para>Can I connect my &windows; box to the Internet via
FreeBSD?</para>
</question>
<answer>
<para>Typically, people who ask this question have two PCs
at home, one with FreeBSD and one with some version of
&windows; the idea is to use the FreeBSD box to connect to
the Internet and then be able to access the Internet from
the &windows; box through the FreeBSD box. This is really
just a special case of the previous question and works
perfectly well.</para>
<para>If you are using dialup to connect to the Internet
user-mode &man.ppp.8; contains a <option>-nat</option>
option. If you run &man.ppp.8; with the
<option>-nat</option> option, set
<literal>gateway_enable</literal> to
<emphasis>YES</emphasis> in
<filename>/etc/rc.conf</filename>, and configure your
&windows; machine correctly, this should work fine. For more
information, please see the &man.ppp.8; manual page or the
<ulink url="&url.books.handbook;/userppp.html">Handbook entry on
user PPP</ulink>.</para>
<para>If you are using kernel-mode PPP or have an Ethernet
connection to the Internet, you need to use
&man.natd.8;. Please look at the <ulink
url="&url.books.handbook;/network-natd.html">natd</ulink> section
of the Handbook for a tutorial.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="slip-ppp-support">
<para>Does FreeBSD support SLIP and PPP?</para>
</question>
<answer>
<para>Yes. See the manual pages for &man.slattach.8;,
&man.sliplogin.8;, &man.ppp.8;, and &man.pppd.8;. &man.ppp.8;
and &man.pppd.8; provide support for both incoming and outgoing
connections, while &man.sliplogin.8; deals exclusively with
incoming connections, and &man.slattach.8; deals exclusively
with outgoing connections.</para>
<para>For more information on how to use these, please see the
<ulink url="&url.books.handbook;/ppp-and-slip.html">Handbook chapter on
PPP and SLIP</ulink>.</para>
<para>If you only have access to the Internet through a
<quote>shell account</quote>, you may want to have a look
at the <filename role="package">net/slirp</filename>
package. It can provide you with (limited) access to
services such as ftp and http direct from your local
machine.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="natd">
<para>Does FreeBSD support NAT or Masquerading?</para>
</question>
<answer>
<para>Yes. If you want to use NAT over a user PPP
connection, please see the <ulink
url="&url.books.handbook;/userppp.html">Handbook entry on user
PPP</ulink>. If you want to use NAT over some other sort
of network connection, please look at the <ulink
url="&url.books.handbook;/network-natd.html">natd</ulink> section
of the Handbook.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="parallel-connect">
<para>How do I connect two FreeBSD systems over a parallel line
using PLIP?</para>
</question>
<answer>
<para>Please see the <ulink url="&url.books.handbook;/plip.html">PLIP
section</ulink> of the Handbook.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="create-dev-net">
<para>Why can I not create a <devicename>/dev/ed0</devicename>
device?</para>
</question>
<answer>
<para>Because they are not necessary. In the Berkeley
networking framework, network interfaces are only directly
accessible by kernel code. Please see the
<filename>/etc/rc.network</filename> file and the manual
pages for the various network programs mentioned there for
more information. If this leaves you totally confused,
then you should pick up a book describing network
administration on another BSD-related operating system;
with few significant exceptions, administering networking
on FreeBSD is basically the same as on &sunos; 4.0 or
Ultrix.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ethernet-aliases">
<para>How can I set up Ethernet aliases?</para>
</question>
<answer>
<para>If the alias is on the same subnet as an address
already configured on the interface, then add
<literal>netmask 0xffffffff</literal> to your
&man.ifconfig.8; command-line, as in the following:</para>
<screen>&prompt.root; <userinput>ifconfig ed0 alias 192.0.2.2 netmask 0xffffffff</userinput></screen>
<para>Otherwise, just specify the network address and
netmask as usual:</para>
<screen>&prompt.root; <userinput>ifconfig ed0 alias 172.16.141.5 netmask 0xffffff00</userinput></screen>
</answer>
</qandaentry>
<qandaentry>
<question id="port-3c503">
<para>How do I get my 3C503 to use the other network
port?</para>
</question>
<answer>
<para>If you want to use the other ports, you will have to specify
an additional parameter on the
&man.ifconfig.8; command line. The default port is
<literal>link0</literal>. To use the AUI port instead of the
BNC one, use <literal>link2</literal>. These flags should be
specified using the ifconfig_* variables in
<filename>/etc/rc.conf</filename> (see &man.rc.conf.5;).</para>
</answer>
</qandaentry>
<qandaentry>
<question id="nfs">
<para>Why am I having trouble with NFS and FreeBSD?</para>
</question>
<answer>
<para>Certain PC network cards are better than others (to put
it mildly) and can sometimes cause problems with network
intensive applications like NFS.</para>
<para>See <ulink url="&url.books.handbook;/nfs.html">
the Handbook entry on NFS</ulink> for more information on
this topic.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="nfs-linux">
<para>Why can I not NFS-mount from a &linux; box?</para>
</question>
<answer>
<para>Some versions of the &linux; NFS code only accept mount
requests from a privileged port; try</para>
<screen>&prompt.root; <userinput>mount -o -P linuxbox:/blah /mnt</userinput></screen>
</answer>
</qandaentry>
<qandaentry>
<question id="nfs-sun">
<para>Why can I not NFS-mount from a Sun box?</para>
</question>
<answer>
<para>&sun; workstations running &sunos; 4.X only accept mount
requests from a privileged port; try</para>
<screen>&prompt.root; <userinput>mount -o -P sunbox:/blah /mnt</userinput></screen>
</answer>
</qandaentry>
<qandaentry>
<question id="exports-errors">
<para>Why does <command>mountd</command> keep telling me it
<errorname>can't change attributes</errorname> and that I have a
<errorname>bad exports list</errorname> on my FreeBSD NFS
server?</para>
</question>
<answer>
<para>The most frequent problem is not understanding the
correct format of <filename>/etc/exports</filename>.
Please review &man.exports.5; and the <ulink
url="&url.books.handbook;/nfs.html">NFS</ulink> entry in the
Handbook, especially the section on <ulink
url="&url.books.handbook;/nfs.html#CONFIGURING-NFS">configuring
NFS</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-nextstep">
<para>Why am I having problems talking PPP to NeXTStep
machines?</para>
</question>
<answer>
<para>Try disabling the TCP extensions in
<filename>/etc/rc.conf</filename> (see &man.rc.conf.5;) by
changing the following variable to NO:</para>
<programlisting>tcp_extensions=NO</programlisting>
<para>Xylogic's Annex boxes are also broken in this regard
and you must use the above change to connect through
them.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ip-multicast">
<para>How do I enable IP multicast support?</para>
</question>
<answer>
<para>FreeBSD supports multicast host operations by
default. If you want your box to run as a multicast
router, you need to recompile your kernel with the
<literal>MROUTING</literal> option and run
&man.mrouted.8;. FreeBSD will start &man.mrouted.8; at
boot time if the flag <literal>mrouted_enable</literal> is
set to <literal>"YES"</literal> in
<filename>/etc/rc.conf</filename>.</para>
<para>MBONE tools are available in their own ports category,
<ulink
url="http://www.FreeBSD.org/ports/mbone.html">mbone</ulink>.
If you are looking for the conference tools
<command>vic</command> and <command>vat</command>, look
there!</para>
</answer>
</qandaentry>
<qandaentry>
<question id="dec-pci-chipset">
<para>Which network cards are based on the DEC PCI
chipset?</para>
</question><answer>
<para>Here is a list compiled by Glen Foster
<email>gfoster@driver.nsta.org</email>,
with some more modern additions:</para>
<table>
<title>Network cards based on the DEC PCI chipset</title>
<tgroup cols=2>
<thead>
<row>
<entry>Vendor</entry>
<entry>Model</entry>
</row>
</thead>
<tbody>
<row>
<entry>ASUS</entry>
<entry>PCI-L101-TB</entry>
</row>
<row>
<entry>Accton</entry>
<entry>ENI1203</entry>
</row>
<row>
<entry>Cogent</entry>
<entry>EM960PCI</entry>
</row>
<row>
<entry>Compex</entry>
<entry>ENET32-PCI</entry>
</row>
<row>
<entry>D-Link</entry>
<entry>DE-530</entry>
</row>
<row>
<entry>Dayna</entry>
<entry>DP1203, DP2100</entry>
</row>
<row>
<entry>DEC</entry>
<entry>DE435, DE450</entry>
</row>
<row>
<entry>Danpex</entry>
<entry>EN-9400P3</entry>
</row>
<row>
<entry>JCIS</entry>
<entry>Condor JC1260</entry>
</row>
<row>
<entry>Linksys</entry>
<entry>EtherPCI</entry>
</row>
<row>
<entry>Mylex</entry>
<entry>LNP101</entry>
</row>
<row>
<entry>SMC</entry>
<entry>EtherPower 10/100 (Model 9332)</entry>
</row>
<row>
<entry>SMC</entry>
<entry>EtherPower (Model 8432)</entry>
</row>
<row>
<entry>TopWare</entry>
<entry>TE-3500P</entry>
</row>
<row>
<entry>Znyx (2.2.x)</entry>
<entry>ZX312, ZX314, ZX342, ZX345, ZX346, ZX348</entry>
</row>
<row>
<entry>Znyx (3.x)</entry>
<entry>ZX345Q, ZX346Q, ZX348Q, ZX412Q, ZX414, ZX442, ZX444,
ZX474, ZX478, ZX212, ZX214 (10mbps/hd)</entry>
</row>
</tbody>
</tgroup>
</table>
</answer>
</qandaentry>
<qandaentry>
<question id="fqdn-hosts">
<para>Why do I have to use the FQDN for hosts on my
site?</para>
</question>
<answer>
<para>You will probably find that the host is actually in a
different domain; for example, if you are in foo.example.org and
you wish to reach a host called <hostid>mumble</hostid> in the
<hostid role="domainname">example.org</hostid> domain, you will
have to refer to it by the fully-qualified domain name, <hostid
role="fqdn">mumble.example.org</hostid>, instead of just
<hostid>mumble</hostid>.</para>
<para>Traditionally, this was allowed by BSD BIND resolvers.
However the current version of
<application>bind</application> (see &man.named.8;)
that ships with FreeBSD no longer provides default
abbreviations for non-fully qualified domain names other than
the domain you are in. So an unqualified host
<hostid>mumble</hostid> must either be found as <hostid
role="fqdn">mumble.foo.example.org</hostid>, or it will be searched
for in the root domain.</para>
<para>This is different from the previous behavior, where the
search continued across
<hostid role="domainname">mumble.example.org</hostid>, and
<hostid role="domainname">mumble.edu</hostid>. Have a look at
RFC 1535 for why this was considered bad practice, or even a
security hole.</para>
<para>As a good workaround, you can place the line</para>
<programlisting>search foo.example.org example.org</programlisting>
<para>instead of the previous</para>
<programlisting>domain foo.example.org</programlisting>
<para>into your <filename>/etc/resolv.conf</filename> file
(see &man.resolv.conf.5;). However, make sure that the
search order does not go beyond the <quote>boundary
between local and public administration</quote>, as RFC
1535 calls it.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="network-permission-denied">
<para>Why do I get an error, <errorname>Permission
denied</errorname>, for all networking operations?</para>
</question>
<answer>
<para>If you have compiled your kernel with the
<literal>IPFIREWALL</literal> option, you need to be aware
that the default policy is to deny all packets that are
not explicitly allowed.</para>
<para>If you had unintentionally misconfigured your system
for firewalling, you can restore network operability by
typing the following while logged in as
<username>root</username>:</para>
<screen>&prompt.root; <userinput>ipfw add 65534 allow all from any to any</userinput></screen>
<para>You can also set
<literal>firewall_type="open"</literal> in
<filename>/etc/rc.conf</filename>.</para>
<para>For further information on configuring a FreeBSD
firewall, see the <ulink url="&url.books.handbook;/firewalls.html">
Handbook section</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ipfw-overhead">
<para>How much overhead does IPFW incur?</para>
</question>
<answer>
<para>Please see the Handbook's <ulink
url="&url.books.handbook;/firewalls.html">Firewalls</ulink>
section, specifically the section on <ulink
url="&url.books.handbook;/firewalls.html#IPFW-OVERHEAD">IPFW
Overhead & Optimization</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ipfw-fwd">
<para>Why is my <command>ipfw</command> <quote>fwd</quote> rule
to redirect a service to another machine not working?</para>
</question>
<answer>
<para>Possibly because you want to do network address translation
(NAT) and not just forward packets. A <quote>fwd</quote> rule
does exactly what it says; it forwards packets. It does not
actually change the data inside the packet. Say we have a rule
like:</para>
<screen>01000 fwd <replaceable>10.0.0.1</replaceable> from any to <replaceable>foo 21</replaceable></screen>
<para>When a packet with a destination address of
<replaceable>foo</replaceable> arrives at the machine with this
rule, the packet is forwarded to
<replaceable>10.0.0.1</replaceable>, but it still has the
destination address of <replaceable>foo</replaceable>! The
destination address of the packet is <emphasis>not</emphasis>
changed to <replaceable>10.0.0.1</replaceable>. Most machines
would probably drop a packet that they receive with a
destination address that is not their own. Therefore, using a
<quote>fwd</quote> rule does not often work the way the user
expects. This behavior is a feature and not a bug.</para>
<para>See the <link linkend="service-redirect">FAQ about
redirecting services</link>, the &man.natd.8; manual, or one of
the several port redirecting utilities in the <ulink
url="&url.base;/ports/index.html">ports collection</ulink> for a correct way to do
this.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="service-redirect">
<para>How can I redirect service requests from one machine to
another?</para>
</question>
<answer>
<para>You can redirect FTP (and other service) request with
the <literal>socket</literal> package, available in the ports
tree in category <quote>sysutils</quote>. Simply replace the
service's command line to call socket instead, like so:</para>
<programlisting>ftp stream tcp nowait nobody /usr/local/bin/socket socket <replaceable>ftp.example.com</replaceable> <replaceable>ftp</replaceable></programlisting>
<para>where <replaceable>ftp.example.com</replaceable> and
<replaceable>ftp</replaceable> are the host and port to
redirect to, respectively.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="bandwidth-mgr-tool">
<para>Where can I get a bandwidth management tool?</para>
</question>
<answer>
<para>There are three bandwidth management tools available
for FreeBSD. &man.dummynet.4; is integrated into FreeBSD
as part of &man.ipfw.4;. <ulink
url="http://www.csl.sony.co.jp/person/kjc/programs.html">ALTQ</ulink>
is available for free on FreeBSD 4.X and has been
integrated into FreeBSD 5.X as part of &man.pf.4;.
Bandwidth Manager from <ulink
url="http://www.etinc.com/">Emerging Technologies</ulink>
is a commercial product.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="bpf-not-configured">
<para>Why do I get <errorname>/dev/bpf0: device not
configured</errorname>?</para>
</question>
<answer>
<para>You are running a program that requires the Berkeley
Packet Filter (&man.bpf.4;), but it is not in your kernel.
Add this to your kernel config file and build a new
kernel:</para>
<programlisting>pseudo-device bpf # Berkeley Packet Filter</programlisting>
<para>On FreeBSD 4.X and earlier, you must also create the
device node. After rebooting, go to the
<filename>/dev</filename> directory and run:</para>
<screen>&prompt.root; <userinput>sh MAKEDEV bpf0</userinput></screen>
<para>Please see the <ulink
url="&url.books.handbook;/kernelconfig-nodes.html"> Handbook entry
on device nodes</ulink> for more information on managing
devices.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="mount-smb-share">
<para>How do I mount a disk from a &windows; machine that is on my
network, like smbmount in &linux;?</para>
</question>
<answer>
<para>Use the <application>SMBFS</application> toolset. It
includes a set of kernel modifications and a set of
userland programs. The programs and information are
available as <filename role="package">net/smbfs</filename>
in the ports collection, or in the base system as of
4.5-RELEASE and later.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="icmp-response-bw-limit">
<para>What are these messages about <quote>icmp-response
bandwidth limit 300/200 pps</quote> in my log
files?</para>
</question>
<answer>
<para>This is the kernel telling you that some activity is
provoking it to send more ICMP or TCP reset (RST)
responses than it thinks it should. ICMP responses are
often generated as a result of attempted connections to
unused UDP ports. TCP resets are generated as a result of
attempted connections to unopened TCP ports. Among
others, these are the kinds of activities which may cause
these messages:</para>
<itemizedlist>
<listitem>
<para>Brute-force denial of service (DoS) attacks (as
opposed to single-packet attacks which exploit a
specific vulnerability).</para>
</listitem>
<listitem>
<para>Port scans which attempt to connect to a large
number of ports (as opposed to only trying a few
well-known ports).</para>
</listitem>
</itemizedlist>
<para>The first number in the message tells you how many
packets the kernel would have sent if the limit was not in
place, and the second number tells you the limit. You can
control the limit using the
<varname>net.inet.icmp.icmplim</varname> sysctl variable
like this, where <literal>300</literal> is the limit in
packets per second:</para>
<screen>&prompt.root; <userinput>sysctl -w net.inet.icmp.icmplim=300</userinput></screen>
<para>If you do not want to see messages about this in your
log files, but you still want the kernel to do response
limiting, you can use the
<varname>net.inet.icmp.icmplim_output</varname> sysctl
variable to disable the output like this:</para>
<screen>&prompt.root; <userinput>sysctl -w net.inet.icmp.icmplim_output=0</userinput></screen>
<para>Finally, if you want to disable response limiting, you
can set the <varname>net.inet.icmp.icmplim</varname>
sysctl variable (see above for an example) to
<literal>0</literal>. Disabling response limiting is
discouraged for the reasons listed above.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="unknown-hw-addr-format">
<para>What are these <errorname>arp: unknown hardware
address format</errorname> error messages?</para>
</question>
<answer>
<para>This means that some device on your local Ethernet is
using a MAC address in a format that FreeBSD does not
recognize. This is probably caused by someone
experimenting with an Ethernet card somewhere else on the
network. You will see this most commonly on cable modem
networks. It is harmless, and should not affect the
performance of your FreeBSD machine.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="cvsup-missing-libs">
<para>I have just installed CVSup but trying to execute it
produces errors. What is wrong?</para>
</question>
<answer>
<para>First, see if the error message you are receiving is
like the one shown below.</para>
<programlisting>/usr/libexec/ld-elf.so.1: Shared object "libXaw.so.6" not found</programlisting>
<para>Errors like these are caused by installing the
<filename role="package">net/cvsup</filename> port on a
machine which does not have the
<application>&xfree86;</application> suite. If you want to
use the <acronym>GUI</acronym> included with
<application>CVSup</application> you will need to install
<application>&xfree86;</application> now. Alternatively if
you just wish to use <application>CVSup</application> from
a command line you should delete the package previously
installed. Then install the <filename
role="package">net/cvsup-without-gui</filename> port. This
is covered in more detail in the <ulink
url="http://www.FreeBSD.org/doc/en_US.ISO8859-1/books/handbook/cvsup.html">CVSup
section</ulink> of the Handbook.</para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter id="security">
<title>Security</title>
<qandaset>
<qandaentry>
<question id="sandbox">
<para>What is a sandbox?</para>
</question><answer>
<para><quote>Sandbox</quote> is a security term. It can
mean two things:</para>
<itemizedlist>
<listitem>
<para>A process which is placed inside a set of virtual
walls that are designed to prevent someone who breaks
into the process from being able to break into the wider
system.</para>
<para>The process is said to be able to
<quote>play</quote> inside the walls. That is,
nothing the process does in regards to executing code is
supposed to be able to breech the walls so you do not
have to do a detailed audit of its code to be able to
say certain things about its security.</para>
<para>The walls might be a userid, for example. This is
the definition used in the &man.security.7; and &man.named.8; man
pages.</para>
<para>Take the <literal>ntalk</literal> service, for
example (see /etc/inetd.conf). This service used to run
as userid <username>root</username>. Now it runs as userid
<username>tty</username>. The <username>tty</username> user
is a sandbox designed to make it more difficult for
someone who has successfully hacked into the system via
ntalk from being able to hack beyond that user id.</para>
</listitem>
<listitem>
<para>A process which is placed inside a simulation of the
machine. This is more hard-core. Basically it means that
someone who is able to break into the process may believe
that he can break into the wider machine but is, in fact,
only breaking into a simulation of that machine and not
modifying any real data.</para>
<para>The most common way to accomplish this is to build a
simulated environment in a subdirectory and then run the
processes in that directory chroot'd (i.e.
<filename>/</filename> for that process is this
directory, not the real <filename>/</filename> of the
system).</para>
<para>Another common use is to mount an underlying
filesystem read-only and then create a filesystem layer
on top of it that gives a process a seemingly writeable
view into that filesystem. The process may believe it is
able to write to those files, but only the process sees
the effects - other processes in the system do not,
necessarily.</para>
<para>An attempt is made to make this sort of sandbox so
transparent that the user (or hacker) does not realize
that he is sitting in it.</para>
</listitem>
</itemizedlist>
<para>&unix; implements two core sandboxes. One is at the
process level, and one is at the userid level.</para>
<para>Every &unix; process is completely firewalled off from every
other &unix; process. One process cannot modify the address
space of another. This is unlike &windows; where a process
can easily overwrite the address space of any other, leading
to a crash.</para>
<para>A &unix; process is owned by a particular userid. If
the userid is not the <username>root</username> user, it
serves to firewall the process off from processes owned by
other users. The userid is also used to firewall off
on-disk data.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="securelevel">
<para>What is securelevel?</para>
</question>
<answer>
<para>The securelevel is a security mechanism implemented in the
kernel. Basically, when the securelevel is positive, the
kernel restricts certain tasks; not even the superuser (i.e.,
<username>root</username>) is allowed to do them. At the time
of this writing, the securelevel mechanism is capable of, among
other things, limiting the ability to,</para>
<itemizedlist>
<listitem>
<para>unset certain file flags, such as
<literal>schg</literal> (the system immutable flag),</para>
</listitem>
<listitem>
<para>write to kernel memory via
<devicename>/dev/mem</devicename> and
<devicename>/dev/kmem</devicename>,</para>
</listitem>
<listitem>
<para>load kernel modules, and</para>
</listitem>
<listitem>
<para>alter firewall rules.</para>
</listitem>
</itemizedlist>
<para>To check the status of the securelevel on a running system,
simply execute the following command:</para>
<screen>&prompt.root; <userinput>sysctl kern.securelevel</userinput></screen>
<para>The output will contain the name of the &man.sysctl.8;
variable (in this case, <varname>kern.securelevel</varname>)
and a number. The latter is the current value of the
securelevel. If it is positive (i.e., greater than 0), at
least some of the securelevel's protections are enabled.</para>
<para>You cannot lower the securelevel of a running system; being
able to do that would defeat its purpose. If you need to do a
task that requires that the securelevel be non-positive (e.g.,
an <maketarget>installworld</maketarget> or changing the date),
you will have to change the securelevel setting in
<filename>/etc/rc.conf</filename> (you want to look for the
<varname>kern_securelevel</varname> and
<varname>kern_securelevel_enable</varname> variables) and
reboot.</para>
<para>For more information on securelevel and the specific things
all the levels do, please consult the &man.init.8; manual
page.</para>
<warning>
<para>Securelevel is not a silver bullet; it has many known
deficiencies. More often than not, it provides a false
sense of security.</para>
<para>One of its biggest problems is that in order for it to
be at all effective, all files used in the boot process up
until the securelevel is set must be protected. If an
attacker can get the system to execute their code prior to
the securelevel being set (which happens quite late in the
boot process since some things the system must do at
start-up cannot be done at an elevated securelevel), its
protections are invalidated. While this task of protecting
all files used in the boot process is not technically
impossible, if it is achieved, system maintenance will
become a nightmare since one would have to take the system
down, at least to single-user mode, to modify a
configuration file.</para>
<para>This point and others are often discussed on the
mailing lists, particularly the &a.security;. Please search
the archives <ulink
url="&url.base;/search/index.html">here</ulink> for an
extensive discussion. Some people are hopeful that
securelevel will soon go away in favor of a more
fine-grained mechanism, but things are still hazy in this
respect.</para>
<para>Consider yourself warned.</para>
</warning>
</answer>
</qandaentry>
<qandaentry>
<question id="extra-named-port">
<para>BIND (<command>named</command>) is listening on port 53 and
some other high-numbered port. What is going on?</para>
</question>
<answer>
<para>BIND uses a random high-numbered port for outgoing
queries. If you want to use port 53 for outgoing queries,
either to get past a firewall or to make yourself feel
better, you can try the following in
<filename>/etc/namedb/named.conf</filename>:</para>
<programlisting>options {
query-source address * port 53;
};</programlisting>
<para>You can replace the <literal>*</literal> with a single IP
address if you want to tighten things further.</para>
<para>Congratulations, by the way. It is good practice to read
your &man.sockstat.1; output and notice odd
things!</para>
</answer>
</qandaentry>
<qandaentry>
<question id="sendmail-port-587">
<para>Sendmail is listening on port 587 as well as the
standard port 25! What is going on?</para>
</question>
<answer>
<para>Recent versions of Sendmail support a
mail submission feature that runs over port 587. This is
not yet widely supported, but is growing in
popularity.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="toor-account">
<para>What is this UID 0 <username>toor</username> account? Have I
been compromised?</para>
</question>
<answer>
<para>Do not worry. <username>toor</username> is an
<quote>alternative</quote> superuser account (toor is root
spelt backwards). Previously it was created when the
&man.bash.1; shell was installed but now it is created by
default. It is intended to be used with a non-standard shell so
you do not have to change <username>root</username>'s default
shell. This is important as shells which are not part of the
base distribution (for example a shell installed from ports or
packages) are likely to be installed in
<filename>/usr/local/bin</filename> which, by default, resides
on a different filesystem. If <username>root</username>'s shell
is located in <filename>/usr/local/bin</filename> and
<filename>/usr</filename> (or whatever filesystem contains
<filename>/usr/local/bin</filename>) is not mounted for some
reason, <username>root</username> will not be able to log in to
fix a problem (although if you reboot into single user mode
you will be prompted for the path to a shell).</para>
<para>Some people use <username>toor</username> for
day-to-day <username>root</username> tasks with a
non-standard shell, leaving <username>root</username>,
with a standard shell, for single user mode or
emergencies. By default you cannot log in using
<username>toor</username> as it does not have a password,
so log in as <username>root</username> and set a password
for <username>toor</username> if you want to use
it.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="suidperl">
<para>Why is <command>suidperl</command> not working
properly?</para>
</question>
<answer>
<para>For security reasons, <command>suidperl</command> is
installed without the suid bit by default. The system
administrator can enable suid behavior with the following
command.</para>
<screen>&prompt.root; <userinput>chmod u+s /usr/bin/suidperl</userinput></screen>
<para>If you want <command>suidperl</command> to be built
suid during upgrades from source, edit
<filename>/etc/make.conf</filename> and add
<varname>ENABLE_SUIDPERL=true</varname> before you run
<command>make buildworld</command>.</para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter id="ppp">
<title>PPP</title>
<qandaset>
<qandaentry>
<question id="userppp">
<para>I cannot make &man.ppp.8; work. What am I doing wrong?</para>
</question>
<answer>
<para>You should first read the &man.ppp.8; manual page and
the <ulink url="&url.books.handbook;/ppp-and-slip.html#USERPPP">
PPP section of the handbook</ulink>. Enable logging with
the command</para>
<programlisting>set log Phase Chat Connect Carrier lcp ipcp ccp command</programlisting>
<para>This command may be typed at the &man.ppp.8; command
prompt or it may be entered in the
<filename>/etc/ppp/ppp.conf</filename> configuration file
(the start of the <literal>default</literal> section is
the best place to put it). Make sure that
<filename>/etc/syslog.conf</filename> (see
&man.syslog.conf.5;) contains the lines</para>
<programlisting>!ppp
*.* /var/log/ppp.log</programlisting>
<para>and that the file <filename>/var/log/ppp.log</filename>
exists. You can now find out a lot about what is going on
from the log file. Do not worry if it does not all make sense.
If you need to get help from someone, it may make sense to
them.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-hangs">
<para>Why does &man.ppp.8; hang when I run it?</para>
</question>
<answer>
<para>This is usually because your hostname will not resolve.
The best way to fix this is to make sure that
<filename>/etc/hosts</filename> is consulted by your
resolver first by editing <filename>/etc/host.conf</filename>
and putting the <literal>hosts</literal> line first. Then,
simply put an entry in <filename>/etc/hosts</filename> for
your local machine. If you have no local network, change your
<hostid>localhost</hostid> line:</para>
<programlisting>127.0.0.1 foo.example.com foo localhost</programlisting>
<para>Otherwise, simply add another entry for your host.
Consult the relevant manual pages for more details.</para>
<para>You should be able to successfully <command>ping -c1
`hostname`</command> when you are done.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-nodial-auto">
<para>Why will &man.ppp.8; not dial in <literal>-auto</literal>
mode?</para>
</question>
<answer>
<para>First, check that you have got a default route. By
running <command>netstat -rn</command> (see
&man.netstat.1;), you should see two entries like
this:</para>
<programlisting>Destination Gateway Flags Refs Use Netif Expire
default 10.0.0.2 UGSc 0 0 tun0
10.0.0.2 10.0.0.1 UH 0 0 tun0</programlisting>
<para>This is assuming that you have used the addresses from the
handbook, the manual page or from the ppp.conf.sample file.
If you do not have a default route, it may be because you are
running an old version of &man.ppp.8;
that does not understand the word <literal>HISADDR</literal>
in the ppp.conf file.</para>
<para>Another reason for the default route line being
missing is that you have mistakenly set up a default
router in your <filename>/etc/rc.conf</filename> (see
&man.rc.conf.5;) file
and you have omitted the line saying</para>
<programlisting>delete ALL</programlisting>
<para>from <filename>ppp.conf</filename>. If this is the
case, go back to the <ulink
url="&url.books.handbook;/ppp-and-slip.html#USERPPP-FINAL"> Final
system configuration</ulink> section of the
handbook.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="no-route-to-host">
<para>What does <errorname>No route to host</errorname> mean?</para>
</question>
<answer>
<para>This error is usually due to a missing</para>
<programlisting>MYADDR:
delete ALL
add 0 0 HISADDR</programlisting>
<para>section in your <filename>/etc/ppp/ppp.linkup</filename>
file. This is only necessary if you have a dynamic IP address
or do not know the address of your gateway. If you are using
interactive mode, you can type the following after entering
<literal>packet mode</literal> (packet mode is
indicated by the capitalized <acronym>PPP</acronym> in the
prompt):</para>
<programlisting>delete ALL
add 0 0 HISADDR</programlisting>
<para>Refer to the <ulink
url="&url.books.handbook;/ppp-and-slip.html#USERPPP-DYNAMICIP">
PPP and Dynamic IP addresses</ulink> section of the handbook
for further details.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="connection-threeminutedrop">
<para>Why does my connection drop after about 3 minutes?</para>
</question>
<answer>
<para>The default PPP timeout is 3 minutes. This can be
adjusted with the line</para>
<programlisting>set timeout <replaceable>NNN</replaceable></programlisting>
<para>where <replaceable>NNN</replaceable> is the number of
seconds of inactivity before the connection is closed. If
<replaceable>NNN</replaceable> is zero, the connection is never
closed due to a timeout. It is possible to put this command in
the <filename>ppp.conf</filename> file, or to type it at the
prompt in interactive mode. It is also possible to adjust it on
the fly while the line is active by connecting to
<application>ppp</application>'s server socket using
&man.telnet.1; or &man.pppctl.8;.
Refer to the
&man.ppp.8; man
page for further details.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-drop-heavy-load">
<para>Why does my connection drop under heavy load?</para>
</question>
<answer>
<para>If you have Link Quality Reporting (LQR) configured,
it is possible that too many LQR packets are lost between
your machine and the peer. Ppp deduces that the line must
therefore be bad, and disconnects. Prior to FreeBSD version
2.2.5, LQR was enabled by default. It is now disabled by
default. LQR can be disabled with the line</para>
<programlisting>disable lqr</programlisting>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-drop-random">
<para>Why does my connection drop after a random amount of
time?</para>
</question>
<answer>
<para>Sometimes, on a noisy phone line or even on a line with
call waiting enabled, your modem may hang up because it
thinks (incorrectly) that it lost carrier.</para>
<para>There is a setting on most modems for determining how
tolerant it should be to temporary losses of carrier. On a
USR &sportster; for example, this is measured by the S10
register in tenths of a second. To make your modem more
forgiving, you could add the following send-expect sequence
to your dial string:</para>
<programlisting>set dial "...... ATS10=10 OK ......"</programlisting>
<para>Refer to your modem manual for details.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-hangs-random">
<para>Why does my connection hang after a random amount of
time?</para>
</question><answer>
<para>Many people experience hung connections with no apparent
explanation. The first thing to establish is which side of
the link is hung.</para>
<para>If you are using an external modem, you can simply try
using &man.ping.8; to see if the <acronym>TD</acronym>
light is flashing when you transmit data. If it flashes
(and the <acronym>RD</acronym> light does not), the
problem is with the remote end. If <acronym>TD</acronym>
does not flash, the problem is local. With an internal
modem, you will need to use the <literal>set
server</literal> command in your
<filename>ppp.conf</filename> file. When the hang occurs,
connect to &man.ppp.8; using &man.pppctl.8;. If your
network connection suddenly revives (PPP was revived due
to the activity on the diagnostic socket) or if you cannot
connect (assuming the <literal>set socket</literal>
command succeeded at startup time), the problem is
local. If you can connect and things are still hung,
enable local async logging with <literal>set log local
async</literal> and use &man.ping.8; from another window
or terminal to make use of the link. The async logging
will show you the data being transmitted and received on
the link. If data is going out and not coming back, the
problem is remote.</para>
<para>Having established whether the problem is local or remote,
you now have two possibilities:</para>
<itemizedlist>
<listitem>
<para>If the problem is remote, read on entry <xref
linkend="ppp-remote-not-responding">.</para>
</listitem>
<listitem>
<para>If the problem is local, read on entry <xref
linkend="ppp-hung">.</para>
</listitem>
</itemizedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-remote-not-responding">
<para>The remote end is not responding. What can I do?</para>
</question>
<answer>
<para>There is very little you can do about this. Most ISPs
will refuse to help if you are not running a Microsoft OS.
You can <literal>enable lqr</literal> in your
<filename>ppp.conf</filename> file, allowing &man.ppp.8; to detect
the remote failure and hang up, but this detection is
relatively slow and therefore not that useful. You may want to
avoid telling your ISP that you are running user-PPP...</para>
<para>First, try disabling all local compression by adding the
following to your configuration:</para>
<programlisting>disable pred1 deflate deflate24 protocomp acfcomp shortseq vj
deny pred1 deflate deflate24 protocomp acfcomp shortseq vj</programlisting>
<para>Then reconnect to ensure that this makes no difference.
If things improve or if the problem is solved completely,
determine which setting makes the difference through trial
and error. This will provide good ammunition when you contact
your ISP (although it may make it apparent that you are not
running a Microsoft product).</para>
<para>Before contacting your ISP, enable async logging
locally and wait until the connection hangs again. This
may use up quite a bit of disk space. The last data read
from the port may be of interest. It is usually ascii
data, and may even describe the problem (<quote>Memory
fault, core dumped</quote>?).</para>
<para>If your ISP is helpful, they should be able to enable
logging on their end, then when the next link drop occurs,
they may be able to tell you why their side is having a
problem. Feel free to send the details to &a.brian;, or
even to ask your ISP to contact me directly.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-hung">
<para>&man.ppp.8; has hung. What can I do?</para>
</question>
<answer>
<para>Your best bet here is to rebuild &man.ppp.8; by adding
<literal>CFLAGS+=-g</literal> and
<literal>STRIP=</literal> to the end of the Makefile, then
doing a <command>make clean &amp;&amp; make &amp;&amp;
make install</command>. When &man.ppp.8; hangs, find the
&man.ppp.8; process id with <command>ps ajxww | fgrep
ppp</command> and run <command>gdb ppp
<replaceable>PID</replaceable></command>. From the gdb
prompt, you can then use <command>bt</command> to get a
stack trace.</para>
<para>Send the results to &a.brian;.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-loginok-thennothing">
<para>Why does nothing happen after the <quote>Login OK!</quote>
message?</para>
</question>
<answer>
<para>Prior to FreeBSD version 2.2.5, once the link was
established, &man.ppp.8; would wait for the peer to
initiate the Line Control Protocol (LCP). Many ISPs will
not initiate negotiations and expect the client to do so.
To force &man.ppp.8; to initiate the LCP, use the
following line:</para>
<programlisting>set openmode active</programlisting>
<note>
<para>It usually does no harm if both sides initiate
negotiation, so openmode is now active by default.
However, the next section explains when it
<emphasis>does</emphasis> do some harm.</para>
</note>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-same-magic">
<para>I keep seeing errors about magic being the same. What does
it mean?</para>
</question>
<answer>
<para>Occasionally, just after connecting, you may see messages
in the log that say <quote>magic is the same</quote>.
Sometimes, these messages are harmless, and sometimes one side
or the other exits. Most PPP implementations cannot survive
this problem, and even if the link seems to come up, you will see
repeated configure requests and configure acknowledgments in
the log file until &man.ppp.8; eventually gives up and closes the
connection.</para>
<para>This normally happens on server machines with slow
disks that are spawning a getty on the port, and executing
&man.ppp.8; from a login script or program after login. I
have also heard reports of it happening consistently when
using slirp. The reason is that in the time taken between
&man.getty.8; exiting and &man.ppp.8; starting, the
client-side &man.ppp.8; starts sending Line Control
Protocol (LCP) packets. Because ECHO is still switched on
for the port on the server, the client &man.ppp.8; sees
these packets <quote>reflect</quote> back.</para>
<para>One part of the LCP negotiation is to establish a
magic number for each side of the link so that
<quote>reflections</quote> can be detected. The protocol
says that when the peer tries to negotiate the same magic
number, a NAK should be sent and a new magic number should
be chosen. During the period that the server port has
ECHO turned on, the client &man.ppp.8; sends LCP packets,
sees the same magic in the reflected packet and NAKs
it. It also sees the NAK reflect (which also means
&man.ppp.8; must change its magic). This produces a
potentially enormous number of magic number changes, all
of which are happily piling into the server's tty
buffer. As soon as &man.ppp.8; starts on the server, it is
flooded with magic number changes and almost immediately
decides it has tried enough to negotiate LCP and gives
up. Meanwhile, the client, who no longer sees the
reflections, becomes happy just in time to see a hangup
from the server.</para>
<para>This can be avoided by allowing the peer to start
negotiating with the following line in your ppp.conf
file:</para>
<programlisting>set openmode passive</programlisting>
<para>This tells &man.ppp.8; to wait for the server to initiate LCP
negotiations. Some servers however may never initiate
negotiations. If this is the case, you can do something
like:</para>
<programlisting>set openmode active 3</programlisting>
<para>This tells &man.ppp.8; to be passive for 3 seconds, and then to
start sending LCP requests. If the peer starts sending
requests during this period, &man.ppp.8; will immediately respond
rather than waiting for the full 3 second period.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-lcp-constant">
<para>LCP negotiations continue until the connection is
closed. What is wrong?</para>
</question>
<answer>
<para>There is currently an implementation mis-feature in
&man.ppp.8; where it does not associate
LCP, CCP &amp; IPCP responses with their original requests. As
a result, if one PPP
implementation is more than 6 seconds slower than the other
side, the other side will send two additional LCP configuration
requests. This is fatal.</para>
<para>Consider two implementations,
<hostid>A</hostid> and
<hostid>B</hostid>. <hostid>A</hostid> starts
sending LCP requests immediately after connecting and
<hostid>B</hostid> takes 7 seconds to start. When
<hostid>B</hostid> starts, <hostid>A</hostid>
has sent 3 LCP REQs. We are assuming the line has ECHO switched
off, otherwise we would see magic number problems as described in
the previous section. <hostid>B</hostid> sends a
REQ, then an ACK to the first of
<hostid>A</hostid>'s REQs. This results in
<hostid>A</hostid> entering the <acronym>OPENED</acronym>
state and sending and ACK (the first) back to
<hostid>B</hostid>. In the meantime,
<hostid>B</hostid> sends back two more ACKs in response to
the two additional REQs sent by <hostid>A</hostid>
before <hostid>B</hostid> started up.
<hostid>B</hostid> then receives the first ACK from
<hostid>A</hostid> and enters the
<acronym>OPENED</acronym> state.
<hostid>A</hostid> receives the second ACK from
<hostid>B</hostid> and goes back to the
<acronym>REQ-SENT</acronym> state, sending another (forth) REQ
as per the RFC. It then receives the third ACK and enters the
<acronym>OPENED</acronym> state. In the meantime,
<hostid>B</hostid> receives the forth REQ from
<hostid>A</hostid>, resulting in it reverting to the
<acronym>ACK-SENT</acronym> state and sending
another (second) REQ and (forth) ACK as per the RFC.
<hostid>A</hostid> gets the REQ, goes into
<acronym>REQ-SENT</acronym> and sends another REQ. It
immediately receives the following ACK and enters
<acronym>OPENED</acronym>.</para>
<para>This goes on until one side figures out that they are
getting nowhere and gives up.</para>
<para>The best way to avoid this is to configure one side to be
<literal>passive</literal> - that is, make one side
wait for the other to start negotiating. This can be done
with the</para>
<programlisting>set openmode passive</programlisting>
<para>command. Care should be taken with this option. You
should also use the</para>
<programlisting>set stopped N</programlisting>
<para>command to limit the amount of time that
&man.ppp.8; waits for the peer to begin
negotiations. Alternatively, the</para>
<programlisting>set openmode active N</programlisting>
<para>command (where <replaceable>N</replaceable> is the
number of seconds to wait before starting negotiations) can be
used. Check the manual page for details.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-shell-test-lockup">
<para>Why does &man.ppp.8; lock up when I shell out to test
it?</para>
</question>
<answer>
<para>When you execute the <command>shell</command> or
<command>!</command> command, &man.ppp.8; executes a
shell (or if you have passed any arguments,
&man.ppp.8; will execute those arguments). Ppp will
wait for the command to complete before continuing. If you
attempt to use the PPP link while running the command, the link
will appear to have frozen. This is because
&man.ppp.8; is waiting for the command to
complete.</para>
<para>If you wish to execute commands like this, use the
<command>!bg</command> command instead. This will execute
the given command in the background, and &man.ppp.8; can
continue to service the link.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-nullmodem">
<para>Why does &man.ppp.8; over a null-modem cable never exit?</para>
</question>
<answer>
<para>There is no way for &man.ppp.8; to
automatically determine that a direct connection has been
dropped. This is due to the lines that are used in a
null-modem serial cable. When using this sort of connection,
LQR should always be enabled with the line</para>
<programlisting>enable lqr</programlisting>
<para>LQR is accepted by default if negotiated by the peer.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-auto-noreasondial">
<para>Why does &man.ppp.8; dial for no reason in -auto mode?</para>
</question><answer>
<para>If &man.ppp.8; is dialing unexpectedly, you must
determine the cause, and set up Dial filters (dfilters) to
prevent such dialing.</para>
<para>To determine the cause, use the following line:</para>
<programlisting>set log +tcp/ip</programlisting>
<para>This will log all traffic through the connection. The
next time the line comes up unexpectedly, you will see the
reason logged with a convenient timestamp next to
it.</para>
<para>You can now disable dialing under these circumstances.
Usually, this sort of problem arises due to DNS lookups.
To prevent DNS lookups from establishing a connection
(this will <emphasis>not</emphasis> prevent &man.ppp.8;
from passing the packets through an established
connection), use the following:</para>
<programlisting>set dfilter 1 deny udp src eq 53
set dfilter 2 deny udp dst eq 53
set dfilter 3 permit 0/0 0/0</programlisting>
<para>This is not always suitable, as it will effectively
break your demand-dial capabilities - most programs will
need a DNS lookup before doing any other network related
things.</para>
<para>In the DNS case, you should try to determine what is
actually trying to resolve a host name. A lot of the
time, &man.sendmail.8; is the culprit. You should make
sure that you tell sendmail not to do any DNS lookups in
its configuration file. See the section on <ulink
url="&url.books.handbook;/smtp-dialup.html">using email with a
dialup connection</ulink> in the FreeBSD Handbook for
details on how to create your own configuration file and
what should go into it. You may also want to add the
following line to your <filename>.mc</filename>
file:</para>
<programlisting>define(`confDELIVERY_MODE', `d')dnl</programlisting>
<para>This will make sendmail queue everything until the
queue is run (usually, sendmail is invoked with
<option>-bd -q30m</option>, telling it to run the queue
every 30 minutes) or until a <command>sendmail
-q</command> is done (perhaps from your ppp.linkup
file).</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ccp-errors">
<para>What do these CCP errors mean?</para>
</question>
<answer>
<para>I keep seeing the following errors in my log file:</para>
<programlisting>CCP: CcpSendConfigReq
CCP: Received Terminate Ack (1) state = Req-Sent (6)</programlisting>
<para>This is because &man.ppp.8; is trying to negotiate Predictor1
compression, and the peer does not want to negotiate any
compression at all. The messages are harmless, but if you
wish to remove them, you can disable Predictor1 compression
locally too:</para>
<programlisting>disable pred1</programlisting>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-connectionspeed">
<para>Why does &man.ppp.8; not log my connection speed?</para>
</question>
<answer>
<para>In order to log all lines of your modem
<quote>conversation</quote>, you must enable the
following:</para>
<programlisting>set log +connect</programlisting>
<para>This will make &man.ppp.8; log
everything up until the last requested <quote>expect</quote>
string.</para>
<para>If you wish to see your connect speed and are using PAP
or CHAP (and therefore do not have anything to
<quote>chat</quote> after the CONNECT in the dial script - no
<literal>set login</literal> script), you must make sure that
you instruct &man.ppp.8; to <quote>expect</quote> the whole CONNECT
line, something like this:</para>
<programlisting>set dial "ABORT BUSY ABORT NO\\sCARRIER TIMEOUT 4 \
\"\" ATZ OK-ATZ-OK ATDT\\T TIMEOUT 60 CONNECT \\c \\n"</programlisting>
<para>Here, we get our CONNECT, send nothing, then expect a
line-feed, forcing &man.ppp.8; to read
the whole CONNECT response.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-ignores-backslash">
<para>Why does &man.ppp.8; ignore the <literal>\</literal> character
in my chat script?</para>
</question><answer>
<para>Ppp parses each line in your config files so that it can
interpret strings such as
<literal>set phone "123 456 789"</literal> correctly and
realize that the number is actually only
<emphasis>one</emphasis> argument. In order to specify a
<literal>&quot;</literal> character, you must escape it
using a backslash (<literal>\</literal>).</para>
<para>When the chat interpreter parses each argument, it
re-interprets the argument in order to find any special
escape sequences such as <literal>\P</literal> or
<literal>\T</literal> (see the manual page). As a result of this
double-parsing, you must remember to use the correct number of
escapes.</para>
<para>If you wish to actually send a <literal>\</literal>
character to (say) your modem, you would need something
like:</para>
<programlisting>set dial "\"\" ATZ OK-ATZ-OK AT\\\\X OK"</programlisting>
<para>resulting in the following sequence:</para>
<programlisting>ATZ
OK
AT\X
OK</programlisting>
<para>or</para>
<programlisting>set phone 1234567
set dial "\"\" ATZ OK ATDT\\T"</programlisting>
<para>resulting in the following sequence:</para>
<programlisting>ATZ
OK
ATDT1234567</programlisting>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-segfault-nocore">
<para>Why does &man.ppp.8; get a seg-fault, but I see no
<filename>ppp.core</filename> file?</para>
</question>
<answer>
<para>Ppp (or any other program for that matter) should
never dump core. Because &man.ppp.8; runs with an
effective user id of 0, the operating system will not
write &man.ppp.8;'s core image to disk before terminating
it. If, however &man.ppp.8; is actually terminating due
to a segmentation violation or some other signal that
normally causes core to be dumped,
<emphasis>and</emphasis> you are sure you are using the
latest version (see the start of this section), then you
should do the following:</para>
<screen>&prompt.user; <userinput>tar xfz ppp-*.src.tar.gz</userinput>
&prompt.user; <userinput>cd ppp*/ppp</userinput>
&prompt.user; <userinput>echo STRIP= &gt;&gt;Makefile</userinput>
&prompt.user; <userinput>echo CFLAGS+=-g &gt;&gt;Makefile</userinput>
&prompt.user; <userinput>make clean all</userinput>
&prompt.user; <userinput>su</userinput>
&prompt.root; <userinput>make install</userinput>
&prompt.root; <userinput>chmod 555 /usr/sbin/ppp</userinput></screen>
<para>You will now have a debuggable version of &man.ppp.8;
installed. You will have to be <username>root</username>
to run &man.ppp.8; as all of its privileges have been
revoked. When you start &man.ppp.8;, take a careful note
of what your current directory was at the time.</para>
<para>Now, if and when &man.ppp.8; receives the segmentation
violation, it will dump a core file called
<filename>ppp.core</filename>. You should then do the
following:</para>
<screen>&prompt.user; <userinput>su</userinput>
&prompt.root; <userinput>gdb /usr/sbin/ppp ppp.core</userinput>
<prompt>(gdb)</prompt> <userinput>bt</userinput>
.....
<prompt>(gdb)</prompt> <userinput>f 0</userinput>
....
<prompt>(gdb)</prompt> <userinput>i args</userinput>
....
<prompt>(gdb)</prompt> <userinput>l</userinput>
.....</screen>
<para>All of this information should be given alongside your
question, making it possible to diagnose the problem.</para>
<para>If you are familiar with gdb, you may wish to find out some
other bits and pieces such as what actually caused the dump and
the addresses &amp; values of the relevant variables.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-autodialprocess-noconnect">
<para>Why does the process that forces a dial in auto mode never
connect?</para>
</question>
<answer>
<para>This was a known problem with
&man.ppp.8; set up to negotiate a
dynamic local IP number with the peer in auto mode. It is
fixed in the latest version - search the manual page for
<literal>iface</literal>.</para>
<para>The problem was that when that initial program calls
&man.connect.2;, the IP number of the tun interface is assigned
to the socket endpoint. The kernel creates the first outgoing
packet and writes it to the tun device.
&man.ppp.8; then reads the packet and
establishes a connection. If, as a result of
&man.ppp.8;'s dynamic IP assignment, the
interface address is changed, the original socket endpoint will
be invalid. Any subsequent packets sent to the peer will
usually be dropped. Even if they are not, any responses will
not route back to the originating machine as the IP number is
no longer owned by that machine.</para>
<para>There are several theoretical ways to approach this
problem. It would be nicest if the peer would re-assign the
same IP number if possible <literal>:-)</literal>
The current version of &man.ppp.8; does
this, but most other implementations do not.</para>
<para>The easiest method from our side would be to never
change the tun interface IP number, but instead to change
all outgoing packets so that the source IP number is
changed from the interface IP to the negotiated IP on the
fly. This is essentially what the
<literal>iface-alias</literal> option in the latest
version of &man.ppp.8; is doing (with the help of
&man.libalias.3; and &man.ppp.8;'s <option>-nat</option>
switch) - it is maintaining all previous interface
addresses and NATing them to the last negotiated
address.</para>
<para>Another alternative (and probably the most reliable) would
be to implement a system call that changes all bound sockets
from one IP to another. &man.ppp.8; would
use this call to modify the sockets of all existing programs
when a new IP number is negotiated. The same system call could
be used by dhcp clients when they are forced to re-bind() their
sockets.</para>
<para>Yet another possibility is to allow an interface to be
brought up without an IP number. Outgoing packets would be
given an IP number of 255.255.255.255 up until the first
SIOCAIFADDR ioctl is done. This would result in fully binding
the socket. It would be up to &man.ppp.8;
to change the source IP number, but only if it is set to
255.255.255.255, and only the IP number and IP checksum would
need to change. This, however is a bit of a hack as the kernel
would be sending bad packets to an improperly configured
interface, on the assumption that some other mechanism is
capable of fixing things retrospectively.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ppp-nat-games">
<para>Why do most games not work with the -nat switch?</para>
</question>
<answer>
<para>The reason games and the like do not work when libalias
is in use is that the machine on the outside will try to open a
connection or send (unsolicited) UDP packets to the machine on
the inside. The NAT software does not know that it should send
these packets to the interior machine.</para>
<para>To make things work, make sure that the only thing
running is the software that you are having problems with, then
either run tcpdump on the tun interface of the gateway or
enable &man.ppp.8; tcp/ip logging (<literal>set log +tcp/ip</literal>)
on the gateway.</para>
<para>When you start the offending software, you should see
packets passing through the gateway machine. When
something comes back from the outside, it will be dropped
(that is the problem). Note the port number of these
packets then shut down the offending software. Do this a
few times to see if the port numbers are consistent. If
they are, then the following line in the relevant section
of <filename>/etc/ppp/ppp.conf</filename> will make the
software functional:</para>
<programlisting>nat port <replaceable>proto</replaceable> <replaceable>internalmachine</replaceable>:<replaceable>port</replaceable> <replaceable>port</replaceable></programlisting>
<para>where <replaceable>proto</replaceable> is either
<literal>tcp</literal> or <literal>udp</literal>,
<replaceable>internalmachine</replaceable> is the machine that
you want the packets to be sent to and
<replaceable>port</replaceable> is the destination port number
of the packets.</para>
<para>You will not be able to use the software on other machines
without changing the above command, and running the software
on two internal machines at the same time is out of the question
- after all, the outside world is seeing your entire internal
network as being just a single machine.</para>
<para>If the port numbers are not consistent, there are three
more options:</para>
<orderedlist>
<listitem>
<para>Submit support in libalias. Examples of
<quote>special cases</quote> can be found in
<filename>/usr/src/lib/libalias/alias_*.c</filename>
(<filename>alias_ftp.c</filename> is a good
prototype). This usually involves reading certain
recognised outgoing packets, identifying the
instruction that tells the outside machine to initiate
a connection back to the internal machine on a
specific (random) port and setting up a
<quote>route</quote> in the alias table so that the
subsequent packets know where to go.</para>
<para>This is the most difficult solution, but it is the
best and will make the software work with multiple
machines.</para>
</listitem>
<listitem>
<para>Use a proxy. The application may support socks5
for example, or (as in the <quote>cvsup</quote> case)
may have a <quote>passive</quote> option that avoids
ever requesting that the peer open connections back to
the local machine.</para>
</listitem>
<listitem>
<para>Redirect everything to the internal machine using
<literal>nat addr</literal>. This is the
sledge-hammer approach.</para>
</listitem>
</orderedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="useful-port-numbers">
<para>Has anybody made a list of useful port numbers?</para>
</question><answer>
<para>Not yet, but this is intended to grow into such a list
(if any interest is shown). In each example,
<replaceable>internal</replaceable> should be replaced with
the IP number of the machine playing the game.</para>
<itemizedlist>
<listitem>
<para><application>Asheron's Call</application></para>
<para><literal>nat port udp
<replaceable>internal</replaceable>
:65000 65000</literal></para>
<para>Manually change the port number within the game to
65000. If you have got a number of machines that you wish
to play on assign a unique port number for each (i.e.
65001, 65002, etc) and add a <literal>nat port</literal>
line for each one.</para>
</listitem>
<listitem>
<para><application>Half Life</application></para>
<para><literal>nat port udp
<replaceable>internal</replaceable>:27005
27015</literal></para>
</listitem>
<listitem>
<para><application>PCAnywhere 8.0</application></para>
<para><literal>nat port udp
<replaceable>internal</replaceable>:5632
5632</literal></para>
<para><literal>nat port tcp
<replaceable>internal</replaceable>:5631
5631</literal></para>
</listitem>
<listitem>
<para><application>Quake</application></para>
<para><literal>nat port udp
<replaceable>internal</replaceable>:6112
6112</literal></para>
<para>Alternatively, you may want to take a look at <ulink
url="http://www.battle.net/support/proxy/">
www.battle.net</ulink> for Quake proxy support.</para>
</listitem>
<listitem>
<para><application>Quake 2</application></para>
<para><literal>nat port udp
<replaceable>internal</replaceable>:27901
27910</literal></para>
<para><literal>nat port udp
<replaceable>internal</replaceable>:60021
60021</literal></para>
<para><literal>nat port udp
<replaceable>internal</replaceable>:60040
60040</literal></para>
</listitem>
<listitem>
<para><application>Red Alert</application></para>
<para><literal>nat port udp
<replaceable>internal</replaceable>:8675
8675</literal></para>
<para><literal>nat port udp
<replaceable>internal</replaceable>:5009
5009</literal></para>
</listitem>
</itemizedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="fcs-errors">
<para>What are FCS errors?</para>
</question>
<answer>
<para>FCS stands for <literal>F</literal>rame
<literal>C</literal>heck <literal>S</literal>equence.
Each PPP packet has a checksum attached to ensure that the
data being received is the data being sent. If the FCS of
an incoming packet is incorrect, the packet is dropped and
the HDLC FCS count is increased. The HDLC error values
can be displayed using the <literal>show hdlc</literal>
command.</para>
<para>If your link is bad (or if your serial driver is dropping
packets), you will see the occasional FCS error. This is not
usually worth worrying about although it does slow down the
compression protocols substantially. If you have an external
modem, make sure your cable is properly shielded from
interference - this may eradicate the problem.</para>
<para>If your link freezes as soon as you have connected and you
see a large number of FCS errors, this may be because your link
is not 8 bit clean. Make sure your modem is not using software
flow control (XON/XOFF). If your datalink
<emphasis>must</emphasis> use software flow control, use the
command <literal>set accmap 0x000a0000</literal> to tell
&man.ppp.8; to escape the <literal>^Q</literal> and
<literal>^S</literal> characters.</para>
<para>Another reason for seeing too many FCS errors may be
that the remote end has stopped talking
<acronym>PPP</acronym>. You may want to enable
<literal>async</literal> logging at this point to
determine if the incoming data is actually a login or
shell prompt. If you have a shell prompt at the remote
end, it is possible to terminate &man.ppp.8; without
dropping the line by using the <literal>close
lcp</literal> command (a following <literal>term</literal>
command will reconnect you to the shell on the remote
machine.</para>
<para>If nothing in your log file indicates why the link might
have been terminated, you should ask the remote administrator
(your ISP?) why the session was terminated.</para>
</answer>
</qandaentry>
<qandaentry id=PPPoEwithNAT>
<question id="macos-win98-pppoe-freeze">
<para>Why do &macos; and &windows; 98 connections freeze when
running PPPoE on the gateway?</para>
</question>
<answer>
<para>Thanks to Michael Wozniak
<email>mwozniak@netcom.ca</email> for figuring this out and
Dan Flemming <email>danflemming@mac.com</email> for the Mac
solution:</para>
<para>This is due to what is called a <quote>Black Hole</quote>
router. &macos; and &windows; 98 (and maybe other Microsoft OSs)
send TCP packets with a requested segment size too big to fit
into a PPPoE frame (MTU is 1500 by default for Ethernet)
<emphasis>and</emphasis> have the <quote>do not
fragment</quote> bit set (default of TCP) and the Telco router
is not sending ICMP <quote>must fragment</quote> back to the
www site you are trying to load. (Alternatively, the router is
sending the ICMP packet correctly, but the firewall at the www
site is dropping it.) When the www server is sending
you frames that do not fit into the PPPoE pipe the Telco router
drops them on the floor and your page does not load (some
pages/graphics do as they are smaller than a MSS.) This seems
to be the default of most Telco PPPoE configurations (if only
they knew how to program a router... sigh...)</para>
<para>One fix is to use regedit on your 95/98 boxes to add the
following registry entry...</para>
<programlisting>HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Class\NetTrans\0000\MaxMTU</programlisting>
<para>It should be a string with a value
<quote>1436</quote>, as some ADSL routers are reported to
be unable to deal with packets larger than this. This
registry key has been changed to
<literal>Tcpip\Parameters\Interfaces\<replaceable>ID for
adapter</replaceable>\MTU</literal> in &windows; 2000 and
becomes a DWORD.</para>
<para>Refer to the Microsoft Knowledge Base documents <ulink
url="http://support.microsoft.com/support/kb/articles/Q158/4/74.asp">Q158474
- Windows TCPIP Registry Entries</ulink> and <ulink
url="http://support.microsoft.com/support/kb/articles/Q120/6/42.asp">Q120642
- TCPIP & NBT Configuration Parameters for &windowsnt;
</ulink> for more information on changing &windows; MTU to
work with a NAT router.</para>
<para>Another regedit possibility under &windows; 2000 is to
set the
<literal>Tcpip\Parameters\Interfaces\<replaceable>ID for
adapter</replaceable>\EnablePMTUBHDetect</literal> DWORD
to 1 as mentioned in the Microsoft document 120642
mentioned above.</para>
<para>Unfortunately, &macos; does not provide an interface for
changing TCP/IP settings. However, there is commercial software
available, such as OTAdvancedTuner (OT for OpenTransport, the
&macos; TCP/IP stack) by <ulink
url="http://www.softworks.com/">Sustainable Softworks</ulink>,
that will allow users to customize TCP/IP settings. &macos; NAT
users should select <literal>ip_interface_MTU</literal> from
the drop-down menu, enter <literal>1450</literal> instead of
<literal>1500</literal> in the box, click the box next to
<literal>Save as Auto Configure</literal>, and click
<literal>Make Active</literal>.</para>
<para>The latest version of &man.ppp.8;
(2.3 or greater) has an <command>enable tcpmssfixup</command>
command that will automatically adjust the MSS to an appropriate
value. This facility is enabled by default. If you are stuck
with an older version of &man.ppp.8;, you
may want to look at the <application>tcpmssd</application>
port.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="desperation">
<para>None of this helps - I am desperate! What can I do?</para>
</question>
<answer>
<para>If all else fails, send as much information as you can,
including your config files, how you are starting
&man.ppp.8;, the relevant parts of your
log file and the output of the <command>netstat -rn</command>
command (before and after connecting) to the &a.questions; or
the <ulink url="news:comp.unix.bsd.freebsd.misc">
comp.unix.bsd.freebsd.misc</ulink> news group, and someone
should point you in the right direction.</para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter id="serial">
<title>Serial Communications</title>
<para>This section answers common questions about serial
communications with FreeBSD. PPP and SLIP are covered in the
<link linkend="networking">Networking</link> section.</para>
<qandaset>
<qandaentry>
<question id="found-serial">
<para>How do I tell if FreeBSD found my serial ports?</para>
</question>
<answer>
<para>As the FreeBSD kernel boots, it will probe for the serial
ports in your system for which the kernel was configured.
You can either watch your system closely for the messages it
prints or run the command</para>
<screen>&prompt.user; <userinput>dmesg | grep sio</userinput></screen>
<para>after your system is up and running.</para>
<para>Here is some example output from the above command:</para>
<programlisting>sio0 at 0x3f8-0x3ff irq 4 on isa
sio0: type 16550A
sio1 at 0x2f8-0x2ff irq 3 on isa
sio1: type 16550A</programlisting>
<para>This shows two serial ports. The first is on irq 4, is
using port address <literal>0x3f8</literal>, and has a
16550A-type UART chip. The second uses the same kind of chip
but is on irq 3 and is at port address <literal>0x2f8</literal>.
Internal modem cards are treated just like serial ports---except
that they always have a modem <quote>attached</quote> to the
port.</para>
<para>The <filename>GENERIC</filename> kernel includes support
for two serial ports using the same irq and port address
settings in the above example. If these settings are not
right for your system, or if you have added modem cards or have
more serial ports than your kernel is configured for, just
reconfigure your kernel. See section
<link linkend="make-kernel">about building a kernel</link> for
more details.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="found-modem">
<para>How do I tell if FreeBSD found my modem cards?</para>
</question>
<answer>
<para>Refer to the answer to the previous question.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="access-serial-ports">
<para>How do I access the serial ports on FreeBSD?</para>
</question>
<answer>
<para>The third serial port, <devicename>sio2</devicename>
(see &man.sio.4;, known as <devicename>COM3</devicename> in DOS), is on
<devicename>/dev/cuaa2</devicename> for dial-out devices,
and on <devicename>/dev/ttyd2</devicename> for dial-in
devices. What is the difference between these two classes
of devices?</para>
<para>You use
<devicename>ttyd<replaceable>X</replaceable></devicename>
for dial-ins. When opening
<devicename>/dev/ttyd<replaceable>X</replaceable></devicename>
in blocking mode, a process will wait for the
corresponding
<devicename>cuaa<replaceable>X</replaceable></devicename>
device to become inactive, and then wait for the carrier
detect line to go active. When you open the
<devicename>cuaa<replaceable>X</replaceable></devicename>
device, it makes sure the serial port is not already in
use by the
<devicename>ttyd<replaceable>X</replaceable></devicename>
device. If the port is available, it <quote>steals</quote>
it from the
<devicename>ttyd<replaceable>X</replaceable></devicename>
device. Also, the
<devicename>cuaa<replaceable>X</replaceable></devicename>
device does not care about carrier detect. With this
scheme and an auto-answer modem, you can have remote users
log in and you can still dial out with the same modem and
the system will take care of all the conflicts.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="enable-multiport-serial">
<para>How do I enable support for a multiport serial
card?</para>
</question>
<answer>
<para>Again, the section on kernel configuration provides
information about configuring your kernel. For a multiport
serial card, place an &man.sio.4; line for each serial
port on the card in the kernel configuration file. But
place the irq and vector specifiers on only one of the
entries. All of the ports on the card should share one
irq. For consistency, use the last serial port to specify
the irq. Also, specify the
<literal>COM_MULTIPORT</literal> option.</para>
<para>The following example is for an AST 4-port serial card on
irq 7:</para>
<programlisting>options "COM_MULTIPORT"
device sio4 at isa? port 0x2a0 tty flags 0x781
device sio5 at isa? port 0x2a8 tty flags 0x781
device sio6 at isa? port 0x2b0 tty flags 0x781
device sio7 at isa? port 0x2b8 tty flags 0x781 irq 7 vector siointr</programlisting>
<para>The flags indicate that the master port has minor number 7
(<literal>0x700</literal>), diagnostics enabled during probe
(<literal>0x080</literal>), and all the ports share an irq
(<literal>0x001</literal>).</para>
</answer>
</qandaentry>
<qandaentry>
<question id="multiport-serial-share-irq">
<para>Can FreeBSD handle multiport serial cards sharing
irqs?</para>
</question>
<answer>
<para>Not yet. You will have to use a different irq for each
card.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="default-serial-params">
<para>Can I set the default serial parameters for a
port?</para>
</question>
<answer>
<para>The
<devicename>ttyd<replaceable>X</replaceable></devicename>
(or
<devicename>cuaa<replaceable>X</replaceable></devicename>)
device is the regular device you will want to open for
your applications. When a process opens the device, it
will have a default set of terminal I/O settings. You can
see these settings with the command</para>
<screen>&prompt.root; <userinput>stty -a -f /dev/ttyd1</userinput></screen>
<para>When you change the settings to this device, the settings
are in effect until the device is closed. When it is reopened,
it goes back to the default set. To make changes to the
default set, you can open and adjust the settings of the
<quote>initial state</quote> device. For example, to turn on
<acronym>CLOCAL</acronym> mode, 8 bits, and
<acronym>XON/XOFF</acronym> flow control by default for
ttyd5, do:</para>
<screen>&prompt.root; <userinput>stty -f /dev/ttyid5 clocal cs8 ixon ixoff</userinput></screen>
<para>A good place to do this is in
<filename>/etc/rc.serial</filename>. Now, an application
will have these settings by default when it opens
<filename>ttyd5</filename>. It can still change these
settings to its liking, though.</para>
<para>You can also prevent certain settings from being
changed by an application by making adjustments to the
<quote>lock state</quote> device. For example, to lock
the speed of <devicename>ttyd5</devicename> to 57600 bps,
do</para>
<screen>&prompt.root; <userinput>stty -f /dev/ttyld5 57600</userinput></screen>
<para>Now, an application that opens
<devicename>ttyd5</devicename> and tries to change the
speed of the port will be stuck with 57600 bps.</para>
<para>Naturally, you should make the initial state and lock
state devices writable only by
<username>root</username>. The &man.MAKEDEV.8; script does
<emphasis>NOT</emphasis> do this when it creates the
device entries.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="enable-dialup">
<para>How can I enable dialup logins on my modem?</para>
</question>
<answer>
<para>So you want to become an Internet service provider, eh?
First, you will need one or more modems that can auto-answer.
Your modem will need to assert carrier-detect when it detects a
carrier and not assert it all the time. It will need to hang up
the phone and reset itself when the data terminal ready
(<acronym>DTR</acronym>) line goes from on to off. It should
probably use <filename>RTS/CTS</filename> flow control or no
local flow control at all. Finally, it must use a constant
speed between the computer and itself, but (to be nice to your
callers) it should negotiate a speed between itself and the
remote modem.</para>
<para>For many Hayes command-set--compatible modems, this
command will make these settings and store them in
nonvolatile memory:</para>
<programlisting>AT &amp;C1 &amp;D3 &amp;K3 &amp;Q6 S0=1 &amp;W</programlisting>
<para>See the section <link linkend="direct-at">on sending AT
commands</link> below for information on how to make these
settings without resorting to an &ms-dos; terminal program.</para>
<para>Next, make an entry in <filename>/etc/ttys</filename>
(see &man.ttys.5;) for the modem. This file lists all the
ports on which the operating system will await logins.
Add a line that looks something like this:</para>
<programlisting>ttyd1 "/usr/libexec/getty std.57600" dialup on insecure</programlisting>
<para>This line indicates that the second serial port
(<devicename>/dev/ttyd1</devicename>) has a modem
connected running at 57600 bps and no parity
(<literal>std.57600</literal>, which comes from the file
<filename>/etc/gettytab</filename>, see &man.gettytab.5;).
The terminal type for this port is
<literal>dialup</literal>. The port is
<literal>on</literal> and is
<literal>insecure</literal>---meaning
<username>root</username> logins on the port are not
allowed. For dialin ports like this one, use the
<devicename>ttyd<replaceable>X</replaceable></devicename>
entry.</para>
<para>It is common practice to use <literal>dialup</literal>
as the terminal type. Many users set up in their
<filename>.profile</filename> or
<filename>.login</filename> files a prompt for the actual
terminal type if the starting type is dialup. The example
shows the port as insecure. To become
<username>root</username> on this port, you have to login
as a regular user, then &man.su.1; to become
<username>root</username>. If you use
<literal>secure</literal> then <username>root</username>
can login in directly.</para>
<para>After making modifications to
<filename>/etc/ttys</filename>, you need to send a hangup
or <acronym>HUP</acronym> signal to the &man.init.8;
process:</para>
<screen>&prompt.root; <userinput>kill -HUP 1</userinput></screen>
<para>This forces the &man.init.8; process to reread
<filename>/etc/ttys</filename>. The init process will
then start getty processes on all <literal>on</literal>
ports. You can find out if logins are available for your
port by typing</para>
<screen>&prompt.user; <userinput>ps -ax | grep '[t]tyd1'</userinput></screen>
<para>You should see something like:</para>
<programlisting>747 ?? I 0:00.04 /usr/libexec/getty std.57600 ttyd1</programlisting>
</answer>
</qandaentry>
<qandaentry>
<question id="dumb-terminal">
<para>How can I connect a dumb terminal to my FreeBSD
box?</para>
</question>
<answer>
<para>If you are using another computer as a terminal into your
FreeBSD system, get a null modem cable to go between the two
serial ports. If you are using an actual terminal, see its
accompanying instructions.</para>
<para>Then, modify <filename>/etc/ttys</filename> (see
&man.ttys.5;), like above. For example, if you are
hooking up a WYSE-50 terminal to the fifth serial port,
use an entry like this:</para>
<programlisting>ttyd4 "/usr/libexec/getty std.38400" wyse50 on secure</programlisting>
<para>This example shows that the port on
<devicename>/dev/ttyd4</devicename> has a wyse50 terminal
connected at 38400 bps with no parity
(<literal>std.38400</literal> from
<filename>/etc/gettytab</filename>, see &man.gettytab.5;)
and <username>root</username> logins are allowed
(<literal>secure</literal>).</para>
</answer>
</qandaentry>
<qandaentry>
<question id="cannot-tip">
<para>Why can I not run <command>tip</command> or
<command>cu</command>?</para>
</question>
<answer>
<para>On your system, the programs &man.tip.1; and
&man.cu.1; are probably executable only by
<username>uucp</username> and group
<groupname>dialer</groupname>. You can use the group
<groupname>dialer</groupname> to control who has access to
your modem or remote systems. Just add yourself to group
dialer.</para>
<para>Alternatively, you can let everyone on your system run
&man.tip.1; and &man.cu.1; by typing:</para>
<screen>&prompt.root; <userinput>chmod 4511 /usr/bin/cu</userinput>
&prompt.root; <userinput>chmod 4511 /usr/bin/tip</userinput></screen>
</answer>
</qandaentry>
<qandaentry>
<question id="hayes-unsupported">
<para>My stock Hayes modem is not supported---what
can I do?</para>
</question>
<answer>
<para>Actually, the manual page for &man.tip.1; is out of
date. There is a generic Hayes dialer already built in.
Just use <literal>at=hayes</literal> in your
<filename>/etc/remote</filename> (see &man.remote.5;)
file.</para>
<para>The Hayes driver is not smart enough to recognize some of
the advanced features of newer modems---messages like
<literal>BUSY</literal>, <literal>NO DIALTONE</literal>, or
<literal>CONNECT 115200</literal> will just confuse it. You
should turn those messages off when you use &man.tip.1;
(using <literal>ATX0&amp;W</literal>).</para>
<para>Also, the dial timeout for &man.tip.1; is 60
seconds. Your modem should use something less, or else tip
will think there is a communication problem. Try
<literal>ATS7=45&amp;W</literal>.</para>
<para>Actually, as shipped &man.tip.1; does not yet
support it fully. The solution is to edit the file
<filename>tipconf.h</filename> in the directory
<filename>/usr/src/usr.bin/tip/tip</filename>. Obviously you
need the source distribution to do this.</para>
<para>Edit the line <literal>#define HAYES 0</literal>
to <literal>#define HAYES 1</literal>. Then
<command>make</command> and <command>make install</command>.
Everything works nicely after that.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="direct-at">
<para>How am I expected to enter these AT commands?</para>
</question>
<answer>
<para>Make what is called a <quote>direct</quote> entry in
your <filename>/etc/remote</filename> file (see
&man.remote.5;). For example, if your modem is hooked up
to the first serial port,
<devicename>/dev/cuaa0</devicename>, then put in the
following line:</para>
<programlisting>cuaa0:dv=/dev/cuaa0:br#19200:pa=none</programlisting>
<para>Use the highest bps rate your modem supports in the br
capability. Then, type <command>tip
<devicename>cuaa0</devicename></command> (see &man.tip.1;)
and you will be connected to your modem.</para>
<para>If there is no <devicename>/dev/cuaa0</devicename> on your
system, do this:</para>
<screen>&prompt.root; <userinput>cd /dev</userinput>
&prompt.root; <userinput>sh MAKEDEV cuaa0</userinput></screen>
<para>Or use cu as <username>root</username> with the
following command:</para>
<screen>&prompt.root; <userinput>cu -l<replaceable>line</replaceable> -s<replaceable>speed</replaceable></userinput></screen>
<para>with <replaceable>line</replaceable> being the serial
port (e.g. <devicename>/dev/cuaa0</devicename>) and
<replaceable>speed</replaceable> being the speed
(e.g.<literal>57600</literal>). When you are done
entering the AT commands hit <literal>~.</literal> to
exit.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="gt-failure">
<para>Why does the <literal>&lt;@&gt;</literal> sign for the pn
capability not work?</para></question><answer>
<para>The <literal>&lt;@&gt;</literal> sign in the phone
number capability tells tip to look in
<filename>/etc/phones</filename> for a phone number. But
the <literal>&lt;@&gt;</literal> sign is also a special
character in capability files like
<filename>/etc/remote</filename>. Escape it with a
backslash:</para>
<programlisting>pn=\@</programlisting>
</answer>
</qandaentry>
<qandaentry>
<question id="dial-command-line">
<para>How can I dial a phone number on the command
line?</para>
</question><answer>
<para>Put what is called a <quote>generic</quote> entry in
your <filename>/etc/remote</filename> file (see
&man.remote.5;). For example:</para>
<programlisting>tip115200|Dial any phone number at 115200 bps:\
:dv=/dev/cuaa0:br#115200:at=hayes:pa=none:du:
tip57600|Dial any phone number at 57600 bps:\
:dv=/dev/cuaa0:br#57600:at=hayes:pa=none:du:</programlisting>
<para>Then you can do something like <command>tip -115200
5551234</command>. If you prefer &man.cu.1; over
&man.tip.1;, use a generic cu entry:</para>
<programlisting>cu115200|Use cu to dial any number at 115200bps:\
:dv=/dev/cuaa1:br#57600:at=hayes:pa=none:du:</programlisting>
<para>and type <command>cu 5551234 -s 115200</command>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="set-bps">
<para>Do I have to type in the bps rate every time I do
that?</para>
</question><answer>
<para>Put in an entry for <literal>tip1200</literal> or
<literal>cu1200</literal>, but go ahead and use whatever
bps rate is appropriate with the br capability.
&man.tip.1; thinks a good default is 1200 bps which is why
it looks for a <literal>tip1200</literal> entry. You do
not have to use 1200 bps, though.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="terminal-server">
<para>How can I more easily access a number of hosts through a
terminal server?</para>
</question>
<answer>
<para>Rather than waiting until you are connected and typing
<literal>CONNECT <replaceable>host</replaceable></literal>
each time, use tip's <literal>cm</literal> capability. For
example, these entries in
<filename>/etc/remote</filename> (see &man.remote.5;):</para>
<programlisting>pain|pain.deep13.com|Forrester's machine:\
:cm=CONNECT pain\n:tc=deep13:
muffin|muffin.deep13.com|Frank's machine:\
:cm=CONNECT muffin\n:tc=deep13:
deep13:Gizmonics Institute terminal server:\
:dv=/dev/cuaa2:br#38400:at=hayes:du:pa=none:pn=5551234:</programlisting>
<para>will let you type <command>tip pain</command> or
<command>tip muffin</command> to connect to the hosts
<hostid>pain</hostid> or <hostid>muffin</hostid>; and
<command>tip deep13</command> to get to the terminal
server.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="tip-multiline">
<para>Can tip try more than one line for each site?</para>
</question>
<answer>
<para>This is often a problem where a university has several
modem lines and several thousand students trying to use
them...</para>
<para>Make an entry for your university in
<filename>/etc/remote</filename> (see &man.remote.5;) and
use <literal>&lt;\@&gt;</literal> for the
<literal>pn</literal> capability:</para>
<programlisting>big-university:\
:pn=\@:tc=dialout
dialout:\
:dv=/dev/cuaa3:br#9600:at=courier:du:pa=none:</programlisting>
<para>Then, list the phone numbers for the university in
<filename>/etc/phones</filename> (see &man.phones.5;):</para>
<programlisting>big-university 5551111
big-university 5551112
big-university 5551113
big-university 5551114</programlisting>
<para>&man.tip.1;
will try each one in the listed order, then give
up. If you want to keep retrying, run &man.tip.1;
in a while loop.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="multi-controlp">
<para>Why do I have to hit <keycombo
action="simul"><keycap>CTRL</keycap><keycap>P</keycap></keycombo>
twice to send <keycombo
action="simul"><keycap>CTRL</keycap><keycap>P</keycap></keycombo>
once?</para>
</question>
<answer>
<para><keycombo
action="simul"><keycap>CTRL</keycap><keycap>P</keycap></keycombo>
is the default <quote>force</quote> character, used to
tell &man.tip.1; that the next character is literal data.
You can set the force character to any other character
with the <literal>~s</literal> escape, which means
<quote>set a variable</quote>.</para>
<para>Type <literal>~sforce=<replaceable>single-char
</replaceable></literal> followed by a newline.
<replaceable>single-char</replaceable> is any single
character. If you leave out
<replaceable>single-char</replaceable>, then the force
character is the nul character, which you can get by
typing <keycombo
action="simul"><keycap>CTRL</keycap><keycap>2</keycap></keycombo>
or <keycombo
action="simul"><keycap>CTRL</keycap><keycap>SPACE</keycap></keycombo>.
A pretty good value for
<replaceable>single-char</replaceable> is <keycombo
action="simul"><keycap>SHIFT</keycap><keycap>CTRL</keycap><keycap>6</keycap></keycombo>,
which I have seen only used on some terminal
servers.</para>
<para>You can have the force character be whatever you want
by specifying the following in your
<filename>$HOME/.tiprc</filename> file:</para>
<programlisting>force=<replaceable>single-char</replaceable></programlisting>
</answer>
</qandaentry>
<qandaentry>
<question id="uppercase">
<para>Why is everything I type suddenly in UPPER CASE?</para>
</question>
<answer>
<para>You must have pressed <keycombo
action="simul"><keycap>CTRL</keycap><keycap>A</keycap></keycombo>,
&man.tip.1; <quote>raise character</quote>, specially
designed for people with broken <keycap>Caps Lock</keycap>
keys. Use <literal>~s</literal> as above and set the
variable <quote>raisechar</quote> to something reasonable.
In fact, you can set it to the same as the force
character, if you never expect to use either of these
features.</para>
<para>Here is a sample .tiprc file perfect for Emacs users
who need to type <keycombo
action="simul"><keycap>CTRL</keycap><keycap>2</keycap></keycombo>
and <keycombo
action="simul"><keycap>CTRL</keycap><keycap>A</keycap></keycombo>
a lot:</para>
<programlisting>force=^^
raisechar=^^</programlisting>
<para>The ^^ is <keycombo action="simul"><keycap>SHIFT</keycap><keycap>CTRL</keycap><keycap>6</keycap></keycombo>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="tip-filetransfer">
<para>How can I do file transfers with
<command>tip</command>?</para>
</question>
<answer>
<para>If you are talking to another &unix; system, you can
send and receive files with <literal>~p</literal> (put)
and <literal>~t</literal> (take). These commands run
&man.cat.1; and &man.echo.1; on the remote system to
accept and send files. The syntax is:</para>
<programlisting>~p &lt;local-file&gt; [&lt;remote-file&gt;]
~t &lt;remote-file&gt; [&lt;local-file&gt;]</programlisting>
<para>There is no error checking, so you probably should use
another protocol, like zmodem.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="zmodem-tip">
<para>How can I run zmodem with
<application>tip</application>?</para>
</question>
<answer>
<para>First, install one of the zmodem programs from the
ports collection (such as one of the two from the comms
category, <application>lrzsz</application> or
<application>rzsz</application>.</para>
<para>To receive files, start the sending program on the
remote end. Then, press enter and type <literal>~C
rz</literal> (or <literal>~C lrz</literal> if you
installed <application>lrzsz</application>) to begin
receiving them locally.</para>
<para>To send files, start the receiving program on the
remote end. Then, press enter and type <literal>~C sz
<replaceable>files</replaceable></literal> (or <literal>~C
lsz <replaceable>files</replaceable></literal>) to send
them to the remote system.</para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter id="misc">
<title>Miscellaneous Questions</title>
<qandaset>
<qandaentry>
<question id="more-swap">
<para>FreeBSD uses far more swap space than &linux;. Why?</para>
</question>
<answer>
<para>FreeBSD only appears to use more swap than &linux;. In
actual fact, it does not. The main difference between FreeBSD
and &linux; in this regard is that FreeBSD will proactively move
entirely idle, unused pages of main memory into swap in order
to make more main memory available for active use. &linux; tends
to only move pages to swap as a last resort. The perceived
heavier use of swap is balanced by the more efficient use of
main memory.</para>
<para>Note that while FreeBSD is proactive in this regard, it
does not arbitrarily decide to swap pages when the system is
truly idle. Thus you will not find your system all paged
out when you get up in the morning after leaving it idle
overnight.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="top-freemem">
<para>Why does <command>top</command> show very little free
memory even when I have very few programs running?</para>
</question>
<answer>
<para>The simple answer is that free memory is wasted
memory. Any memory that your programs do not actively
allocate is used within the FreeBSD kernel as disk
cache. The values shown by &man.top.1; labeled as
<literal>Inact</literal>, <literal>Cache</literal>, and
<literal>Buf</literal> are all cached data at different
aging levels. This cached data means the system does
not have to access a slow disk again for data it has
accessed recently, thus increasing overall performance.
In general, a low value shown for <literal>Free</literal>
memory in &man.top.1; is good, provided it is not
<emphasis>very</emphasis> low.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="chmod-symlinks">
<para>Why will <command>chmod</command> not change the
permissions on symlinks?</para>
</question>
<answer>
<para>Symlinks do not have permissions, and by default,
&man.chmod.1; will not follow symlinks to change the
permissions on the target file. So if you have a file,
<filename>foo</filename>, and a symlink to that file,
<filename>bar</filename>, then this command will always
succeed.</para>
<screen>&prompt.user; <userinput>chmod g-w bar</userinput></screen>
<para>However, the permissions on <filename>foo</filename> will
not have changed.</para>
<para>You have to use either <option>-H</option> or
<option>-L</option> together with the <option>-R</option>
option to make this work. See the &man.chmod.1; and
&man.symlink.7; manual pages for more info.</para>
<warning>
<para>The <option>-R</option> option does a
<emphasis>RECURSIVE</emphasis> &man.chmod.1;. Be
careful about specifying directories or symlinks to
directories to &man.chmod.1;. If you want to change
the permissions of a directory referenced by a
symlink, use &man.chmod.1; without any options and
follow the symlink with a trailing slash
(<filename>/</filename>). For example, if
<filename>foo</filename> is a symlink to directory
<filename>bar</filename>, and you want to change the
permissions of <filename>foo</filename> (actually
<filename>bar</filename>), you would do something
like:</para>
<screen>&prompt.user; <userinput>chmod 555 foo/</userinput></screen>
<para>With the trailing slash, &man.chmod.1; will follow
the symlink, <filename>foo</filename>, to change the
permissions of the directory,
<filename>bar</filename>.</para>
</warning>
</answer>
</qandaentry>
<qandaentry>
<question id="dos-binaries">
<para>Can I run DOS binaries under FreeBSD?</para>
</question>
<answer>
<para>Yes, you can use <filename
role="package">emulators/doscmd</filename>, a DOS emulation
program, available in the &os; Ports Collection.</para>
<note>
<para>The <application>doscmd</application> program used to be an
integrated part of &os;, but was removed before the release of
&os; 5.3.</para>
</note>
<para>If <application>doscmd</application> will not suffice,
the add-on utility <filename
role="package">emulators/pcemu</filename> emulates an 8088 and
enough BIOS services to run many DOS text mode
applications. It requires the X Window System.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="translation">
<para>What do I need to do to translate a FreeBSD document into
my native language?</para>
</question>
<answer>
<para>See the <ulink url="&url.books.fdp-primer;/translations.html">
Translation FAQ</ulink> in the FreeBSD Documentation Project
Primer.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="freebsd-mail-bounces">
<para>Why does my email to any address at FreeBSD.org bounce?</para>
</question>
<answer>
<para>The FreeBSD.org mail system implements some of the
stricter Postfix checks on incoming mail and rejects mail that is
either misconfigured or is potential spam. Your mail
might bounce for one of the following reasons:</para>
<itemizedlist>
<listitem>
<para>The email is being sent from a known spam
domain or IP block.</para>
<para>The FreeBSD mail servers reject email from known
spam sources. If you have service through a company
or domain who generates or relays spam, please switch
to a service provider who does not.</para>
</listitem>
<listitem>
<para>The body of the email only contains HTML.</para>
<para>Mail should be sent in plain text only. Please
configure your mail user agent to send plain
text.</para>
</listitem>
<listitem>
<para>The mailer at FreeBSD.org cannot resolve the IP
address of the connecting host back to a symbolic
name.</para>
<para>Working reverse DNS is a standard requirement for
accepting mail from a host. Set up reverse DNS for
your mail server's IP address. Many home services
(DSL, cable, dialup, etc.) will not give you this
option. In this case, relay your email through your
service provider's mail server.</para>
</listitem>
<listitem>
<para>The hostname given in the EHLO/HELO part of the SMTP
exchange cannot be resolved to an IP address.</para>
<para>A fully qualified, resolvable host name is necessary
in this part of the SMTP dialogue before mail will be
accepted. If you do not have a host name that is registered
in the DNS, then you should use your service provider's mail
server to relay your mail.</para>
</listitem>
<listitem>
<para>Your message had a message ID ending with the string
<quote>localhost</quote>.</para>
<para>Some mail user agents generate bad message IDs which will
not be accepted. You will need to persuade your mail user
agent to generate a valid message ID or else configure your
mail transfer agent to rewrite them.</para>
</listitem>
</itemizedlist>
</answer>
</qandaentry>
<qandaentry>
<question id="free-account">
<para>Where can I find a free FreeBSD account?</para>
</question>
<answer>
<para>While FreeBSD does not provide open access to any of their
servers, others do provide open access &unix; systems. The
charge varies and limited services may be available.</para>
<para><ulink url="http://www.arbornet.org/">Arbornet,
Inc</ulink>, also known as M-Net, has been providing open
access to &unix; systems since 1983. Starting on an Altos
running System III, the site switched to BSD/OS in 1991. In
June of 2000, the site switched again to FreeBSD. M-Net can be
accessed via telnet and SSH and provides basic access to the
entire FreeBSD software suite. However, network access is
limited to members and patrons who donate to the system, which
is run as a non-profit organization. M-Net also provides an
bulletin board system and interactive chat.</para>
<para><ulink url="http://www.grex.org/">Grex</ulink> provides a
site very similar to M-Net including the same bulletin board
and interactive chat software. However, the machine is a &sun;
4M and is running &sunos;.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="sup-define">
<para>What is <command>sup</command>, and how do I use
it?</para>
</question>
<answer>
<para><ulink url="http://www.FreeBSD.org/cgi/ports.cgi?^sup">
SUP</ulink> stands for Software Update Protocol, and was
developed by CMU for keeping their development trees in sync.
We used it to keep remote sites in sync with our central
development sources.</para>
<para>SUP is not bandwidth friendly, and has been retired.
The current recommended method to keep your sources up to
date is <ulink url="&url.books.handbook;/synching.html#CVSUP">
CVSup</ulink></para>
</answer>
</qandaentry>
<qandaentry>
<question id="daemon-name">
<para>What is the cute little red guy's name?</para>
</question>
<answer>
<para>He does not have one, and is just called <quote>the BSD
daemon</quote>. If you insist upon using a name, call him
<quote>beastie</quote>. Note that <quote>beastie</quote>
is pronounced <quote>BSD</quote>.</para>
<para>You can learn more about the BSD daemon on his <ulink
url="http://www.mckusick.com/beastie/index.html">home
page</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="use-beastie">
<para>Can I use the BSD daemon image?</para>
</question>
<answer>
<para>Perhaps. The BSD daemon is copyrighted by Marshall
Kirk McKusick. You will want to check his <ulink
url="http://www.mckusick.com/beastie/mainpage/copyright.html">Statement
on the Use of the BSD Daemon Figure</ulink> for detailed
usage terms.</para>
<para>In summary, you are free to use the image in a tasteful
manner, for personal use, so long as appropriate credit is
given. If you want to use him commercially, you must
contact Kirk McKusick. More details are available on the
<ulink
url="http://www.mckusick.com/beastie/index.html">BSD
Daemon's home page</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="daemon-images">
<para>Do you have any BSD daemon images I could use?</para>
</question>
<answer>
<para>You will find eps and Xfig drawings under
<filename>/usr/share/examples/BSD_daemon/</filename>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="define-MFC">
<para>What does <acronym>MFC</acronym> mean?</para>
</question>
<answer>
<para>MFC is an acronym for <quote>Merged From -CURRENT</quote>.
It is used in the CVS logs to denote when a change was
migrated from the CURRENT to the STABLE branches.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="define-BSD">
<para>What does <acronym>BSD</acronym> mean?</para>
</question>
<answer>
<para>It stands for something in a secret language that only
members can know. It does not translate literally but it is ok
to tell you that BSD's translation is something between,
<quote>Formula-1 Racing Team</quote>, <quote>Penguins are
tasty snacks</quote>, and <quote>We have a better sense of
humor than &linux;</quote>. :-)</para>
<para>Seriously, BSD is an acronym for <quote>Berkeley
Software Distribution</quote>, which is the name the
Berkeley <acronym>CSRG</acronym> (Computer Systems Research
Group) chose for their &unix; distribution way back when.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="define-pola">
<para>What does <acronym>POLA</acronym> mean?</para>
</question>
<answer>
<para>Principle of Least Astonishment. It means that as
FreeBSD evolves, changes visible to the user should be
kept as unsurprising as possible. For example,
arbitrarily rearranging system startup variables in
<filename>/etc/defaults/rc.conf</filename> violates POLA.
Developers consider POLA when contemplating user-visible
system changes.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="define-repocopy">
<para>What is a repo-copy?</para>
</question>
<answer>
<para>A repo-copy (which is a short form of <quote>repository
copy</quote>) refers to the direct copying of files within
the CVS repository.</para>
<para>Without a repo-copy, if a file needed to be copied or
moved to another place in the repository, the committer would
run <command>cvs add</command> to put the file in its new
location, and then <command>cvs rm</command> on the old file
if the old copy was being removed.</para>
<para>The disadvantage of this method is that the history
(i.e. the entries in the CVS logs) of the file would not be
copied to the new location. As the FreeBSD Project considers
this history very useful, a repository copy is often used
instead. This is a process where one of the repository meisters
will copy the files directly within the repository, rather than
using the &man.cvs.1; program.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="bikeshed-painting">
<para>Why should I care what color the bikeshed is?</para>
</question>
<answer>
<para>The really, really short answer is that you should not.
The somewhat longer answer is that just because you are
capable of building a bikeshed does not mean you should stop
others from building one just because you do not like the
color they plan to paint it. This is a metaphor indicating
that you need not argue about every little feature just
because you know enough to do so. Some people have
commented that the amount of noise generated by a change is
inversely proportional to the complexity of the
change.</para>
<para>The longer and more complete answer is that after a very
long argument about whether &man.sleep.1; should take
fractional second arguments, &a.phk; posted a long
message entitled <quote><ulink
url="http://www.FreeBSD.org/cgi/getmsg.cgi?fetch=506636+517178+/usr/local/www/db/text/1999/freebsd-hackers/19991003.freebsd-hackers">A bike
shed (any color will do) on greener grass...</ulink></quote>.
The appropriate portions of that message are quoted
below.</para>
<blockquote>
<attribution>&a.phk; on freebsd-hackers, October
2, 1999</attribution>
<para>
<quote>What is it about this bike shed?</quote> Some
of you have asked me.</para>
<para>It is a long story, or rather it is an old story, but
it is quite short actually. C. Northcote Parkinson wrote
a book in the early 1960s, called <quote>Parkinson's
Law</quote>, which contains a lot of insight into the
dynamics of management.</para>
<para>[snip a bit of commentary on the book]</para>
<para>In the specific example involving the bike shed, the
other vital component is an atomic power-plant, I guess
that illustrates the age of the book.</para>
<para>Parkinson shows how you can go into the board of
directors and get approval for building a multi-million or
even billion dollar atomic power plant, but if you want to
build a bike shed you will be tangled up in endless
discussions.</para>
<para>Parkinson explains that this is because an atomic
plant is so vast, so expensive and so complicated that
people cannot grasp it, and rather than try, they fall
back on the assumption that somebody else checked all the
details before it got this far. Richard P. Feynmann
gives a couple of interesting, and very much to the point,
examples relating to Los Alamos in his books.</para>
<para>A bike shed on the other hand. Anyone can build one
of those over a weekend, and still have time to watch the
game on TV. So no matter how well prepared, no matter how
reasonable you are with your proposal, somebody will seize
the chance to show that he is doing his job, that he is
paying attention, that he is
<emphasis>here</emphasis>.</para>
<para>In Denmark we call it <quote>setting your
fingerprint</quote>. It is about personal pride and
prestige, it is about being able to point somewhere and
say <quote>There! <emphasis>I</emphasis> did that.</quote>
It is a strong trait in politicians, but present in most
people given the chance. Just think about footsteps in
wet cement.</para>
</blockquote>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter id="funnies">
<title>The FreeBSD Funnies</title>
<qandaset>
<qandaentry>
<question id="very-very-cool">
<para>How cool is FreeBSD?</para>
</question>
<answer>
<para>Q. Has anyone done any temperature testing while
running FreeBSD? I know &linux; runs cooler than DOS, but have
never seen a mention of FreeBSD. It seems to run really
hot.</para>
<para>A. No, but we have done numerous taste tests on
blindfolded volunteers who have also had 250 micrograms of
LSD-25 administered beforehand. 35% of the volunteers said that
FreeBSD tasted sort of orange, whereas &linux; tasted like purple
haze. Neither group mentioned any significant variances in
temperature. We eventually had to throw the
results of this survey out entirely anyway when we found that
too many volunteers were wandering out of the room during the
tests, thus skewing the results. We think most of the volunteers
are at Apple now, working on their new <quote>scratch and
sniff</quote> GUI. It is a funny old business we are in!</para>
<para>Seriously, both FreeBSD and &linux; use the
<acronym>HLT</acronym> (halt) instruction when the system is
idle thus lowering its energy consumption and therefore the
heat it generates. Also if you have APM (advanced power
management) configured, then FreeBSD can also put the CPU into
a low power mode.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="letmeoutofhere">
<para>Who is scratching in my memory banks??</para>
</question>
<answer>
<para>Q. Is there anything <quote>odd</quote> that FreeBSD
does when compiling the kernel which would cause the memory to
make a scratchy sound? When compiling (and for a brief moment
after recognizing the floppy drive upon startup, as well), a
strange scratchy sound emanates from what appears to be the
memory banks.</para>
<para>A. Yes! You will see frequent references to
<quote>daemons</quote> in the BSD documentation, and what most
people do not know is that this refers to genuine, non-corporeal
entities that now possess your computer. The scratchy sound
coming from your memory is actually high-pitched whispering
exchanged among the daemons as they best decide how to deal
with various system administration tasks.</para>
<para>If the noise gets to you, a good
<command>fdisk /mbr</command> from DOS will get rid of them,
but do not be surprised if they react adversely and try to stop
you. In fact, if at any point during the exercise you hear the
satanic voice of Bill Gates coming from the built-in speaker,
take off running and do not ever look back! Freed from the
counterbalancing influence of the BSD daemons, the twin demons
of DOS and &windows; are often able to re-assert total control
over your machine to the eternal damnation of your soul.
Now that you know, given a choice you would probably prefer to get
used to the scratchy noises, no?</para>
</answer>
</qandaentry>
<qandaentry>
<question id="changing-lightbulbs">
<para>How many FreeBSD hackers does it take to change a
lightbulb?</para>
</question>
<answer>
<para>One thousand, one hundred and sixty-nine:</para>
<para>Twenty-three to complain to -CURRENT about the lights
being out;</para>
<para>Four to claim that it is a configuration problem, and
that such matters really belong on -questions;</para>
<para>Three to submit PRs about it, one of which is misfiled
under doc and consists only of <quote>it's dark</quote>;</para>
<para>One to commit an untested lightbulb which breaks
buildworld, then back it out five minutes later;</para>
<para>Eight to flame the PR originators for not including
patches in their PRs;</para>
<para>Five to complain about buildworld being broken;</para>
<para>Thirty-one to answer that it works for them, and they
must have cvsupped at a bad time;</para>
<para>One to post a patch for a new lightbulb to -hackers;</para>
<para>One to complain that he had patches for this three years
ago, but when he sent them to -CURRENT they were just ignored,
and he has had bad experiences with the PR system; besides,
the proposed new lightbulb is non-reflexive;</para>
<para>Thirty-seven to scream that lightbulbs do not belong in
the base system, that committers have no right to do things
like this without consulting the Community, and WHAT IS
-CORE DOING ABOUT IT!?</para>
<para>Two hundred to complain about the color of the bicycle
shed;</para>
<para>Three to point out that the patch breaks &man.style.9;;</para>
<para>Seventeen to complain that the proposed new lightbulb is
under GPL;</para>
<para>Five hundred and eighty-six to engage in a flame war
about the comparative advantages of the GPL, the BSD
license, the MIT license, the NPL, and the personal hygiene
of unnamed FSF founders;</para>
<para>Seven to move various portions of the thread to -chat
and -advocacy;</para>
<para>One to commit the suggested lightbulb, even though it
shines dimmer than the old one;</para>
<para>Two to back it out with a furious flame of a commit
message, arguing that FreeBSD is better off in the dark than
with a dim lightbulb;</para>
<para>Forty-six to argue vociferously about the backing out
of the dim lightbulb and demanding a statement from
-core;</para>
<para>Eleven to request a smaller lightbulb so it will fit
their Tamagotchi if we ever decide to port FreeBSD to that
platform;</para>
<para>Seventy-three to complain about the SNR on -hackers and
-chat and unsubscribe in protest;</para>
<para>Thirteen to post <quote>unsubscribe</quote>,
<quote>How do I unsubscribe?</quote>, or <quote>Please
remove me from the list</quote>, followed by the usual
footer;</para>
<para>One to commit a working lightbulb while everybody is too
busy flaming everybody else to notice;</para>
<para>Thirty-one to point out that the new lightbulb would shine
0.364% brighter if compiled with TenDRA (although it will have
to be reshaped into a cube), and that FreeBSD should therefore
switch to TenDRA instead of GCC;</para>
<para>One to complain that the new lightbulb lacks
fairings;</para>
<para>Nine (including the PR originators) to ask
<quote>what is MFC?</quote>;</para>
<para>Fifty-seven to complain about the lights being out two
weeks after the bulb has been changed.</para>
<para><emphasis>&a.nik; adds:</emphasis></para>
<para><emphasis>I was laughing quite hard at
this.</emphasis></para>
<para><emphasis>And then I thought, <quote>Hang on,
shouldn't there be '1 to document it.' in that list
somewhere?</quote></emphasis></para>
<para><emphasis>And then I was enlightened :-)</emphasis></para>
</answer>
</qandaentry>
<qandaentry>
<question id="dev-null">
<para>Where does data written to <filename>/dev/null</filename>
go?</para>
</question>
<answer>
<para>It goes into a special data sink in the CPU where it
is converted to heat which is vented through the heatsink
/ fan assembly. This is why CPU cooling is increasingly
important; as people get used to faster processors, they
become careless with their data and more and more of it
ends up in <filename>/dev/null</filename>, overheating
their CPUs. If you delete <filename>/dev/null</filename>
(which effectively disables the CPU data sink) your CPU
may run cooler but your system will quickly become
constipated with all that excess data and start to behave
erratically. If you have a fast network connection you
can cool down your CPU by reading data out of
<filename>/dev/random</filename> and sending it off
somewhere; however you run the risk of overheating your
network connection and <filename>/</filename> or angering
your ISP, as most of the data will end up getting
converted to heat by their equipment, but they generally
have good cooling, so if you do not overdo it you should be
OK.</para>
<para><emphasis>Paul Robinson adds:</emphasis></para>
<para>There are other methods. As every good sysadmin knows,
it is part of standard practice to send data to the screen
of interesting variety to keep all the pixies that make up
your picture happy. Screen pixies (commonly mis-typed or
re-named as <quote>pixels</quote> are categorized by the type of hat
they wear (red, green or blue) and will hide or appear
(thereby showing the color of their hat) whenever they
receive a little piece of food. Video cards turn data into
pixie-food, and then send them to the pixies - the more
expensive the card, the better the food, so the better
behaved the pixies are. They also need constant stimulation
- this is why screen savers exist.</para>
<para>To take your suggestions further, you could just throw
the random data to console, thereby letting the pixies
consume it. This causes no heat to be produced at all,
keeps the pixies happy and gets rid of your data quite
quickly, even if it does make things look a bit messy on
your screen.</para>
<para>Incidentally, as an ex-admin of a large ISP who
experienced many problems attempting to maintain a stable
temperature in a server room, I would strongly discourage
people sending the data they do not want out to the
network. The fairies who do the packet switching and
routing get annoyed by it as well.</para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter id="advanced">
<title>Advanced Topics</title>
<qandaset>
<qandaentry>
<question id="learn-advanced">
<para>How can I learn more about FreeBSD's internals?</para>
</question>
<answer>
<para>At this time, there is only one book on FreeBSD-specific OS
internals, namely <quote>The Design and Implementation of the
FreeBSD Operating System</quote> by Marshall Kirk McKusick and
George V. Neville-Neil, ISBN 0-201-70245-2, which
focuses on version 5.X of FreeBSD.</para>
<para>Additionally, much general &unix; knowledge is directly
applicable to FreeBSD.</para>
<para>For a list of relevant books, please check the Handbook's <ulink
url="&url.books.handbook;/bibliography-osinternals.html">Operating
System Internals Bibliography</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="how-to-contribute">
<para>How can I contribute to FreeBSD?</para>
</question>
<answer>
<para>Please see the article on <ulink
url="&url.articles.contributing;/article.html">Contributing
to FreeBSD</ulink> for specific advice on how to do this.
Assistance is more than welcome!</para>
</answer>
</qandaentry>
<qandaentry>
<question id="define-snap-release">
<para>What are SNAPs and RELEASEs?</para>
</question>
<answer>
<para>There are currently three active/semi-active branches
in the FreeBSD <ulink
url="http://www.FreeBSD.org/cgi/cvsweb.cgi"> CVS
Repository</ulink>. (Earlier branches are only changed
very rarely, which is why there are only three active
branches of development):</para>
<itemizedlist>
<listitem>
<para><literal>RELENG_4</literal> AKA
<emphasis>4-STABLE</emphasis></para>
</listitem>
<listitem>
<para><literal>RELENG_5</literal> AKA
<emphasis>5-STABLE</emphasis></para>
</listitem>
<listitem>
<para><literal>HEAD</literal> AKA
<emphasis>-CURRENT</emphasis> AKA
<emphasis>6.X-CURRENT</emphasis></para>
</listitem>
</itemizedlist>
<para><literal>HEAD</literal> is not an actual branch tag,
like the other two; it is simply a symbolic constant for
<quote><emphasis>the current, non-branched development
stream</emphasis></quote> which we simply refer to as
<quote>-CURRENT</quote>.</para>
<para>Right now, <quote>-CURRENT</quote> is the 6.X development
stream; the <literal>4-STABLE</literal> branch,
<symbol>RELENG_4</symbol>, forked off from
<quote>-CURRENT</quote> in March 2000, and
the <literal>5-STABLE</literal> branch,
<symbol>RELENG_5</symbol>, forked off from
<quote>-CURRENT</quote> in October 2004.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="custrel">
<para>How do I make my own custom release?</para>
</question>
<answer>
<para>Please see the <ulink
url="&url.articles.releng;/article.html">
Release Engineering</ulink> article.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="makeworld-clobbers">
<para>Why does <command>make world</command> clobber my existing
installed binaries?</para>
</question>
<answer>
<para>Yes, this is the general idea; as its name might suggest,
<command>make world</command> rebuilds every system binary from
scratch, so you can be certain of having a clean and consistent
environment at the end (which is why it takes so long).</para>
<para>If the environment variable <literal>DESTDIR</literal>
is defined while running <command>make world</command> or
<command>make install</command>, the newly-created binaries
will be deposited in a directory tree identical to the
installed one, rooted at <literal>${DESTDIR}</literal>.
Some random combination of shared libraries modifications and
program rebuilds can cause this to fail in <command>make
world</command> however.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="cvsup-round-robin">
<para>Why isn't cvsup.FreeBSD.org a round robin DNS entry to
share the load amongst the various CVSup servers?</para>
</question>
<answer>
<para>While CVSup mirrors update from the master CVSup
server hourly, this update might happen at any time during
the hour. This means that some servers have newer code
than others, even though all servers have code that is
less than an hour old. If <hostid role="fqdn">cvsup.FreeBSD.org</hostid> was a round
robin DNS entry that simply redirected users to a random
CVSup server, running CVSup twice in a row could download
code older than the code already on the system.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="bus-speed-defaulted">
<para>Why does my system say <quote>(bus speed
defaulted)</quote> when it boots?</para>
</question>
<answer>
<para>The Adaptec 1542 SCSI host adapters allow the user to
configure their bus access speed in software. Previous versions
of the 1542 driver tried to determine the fastest usable speed
and set the adapter to that. We found that this breaks some
users' systems, so you now have to define the
<symbol>TUNE_1542</symbol> kernel configuration option in order
to have this take place. Using it on those systems where it
works may make your disks run faster, but on those systems
where it does not, your data could be corrupted.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="ctm">
<para>Can I follow -CURRENT with limited Internet access?</para>
</question>
<answer>
<para>Yes, you can do this <emphasis>without</emphasis>
downloading the whole source tree by using the <ulink
url="&url.books.handbook;/synching.html#CTM">CTM facility</ulink>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="split-240k">
<para>How did you split the distribution into 240k files?</para>
</question>
<answer>
<para>Newer BSD based systems have a <option>-b</option>
option to &man.split.1; that allows them to split files on arbitrary
byte boundaries.</para>
<para>Here is an example from
<filename>/usr/src/Makefile</filename>.</para>
<programlisting>bin-tarball:
(cd ${DISTDIR}; \
tar cf - . \
gzip --no-name -9 -c | \
split -b 240640 - \
${RELEASEDIR}/tarballs/bindist/bin_tgz.)</programlisting>
</answer>
</qandaentry>
<qandaentry>
<question id="submitting-kernel-extensions">
<para>I have written a kernel extension, who do I send it
to?</para>
</question>
<answer>
<para>Please take a look at the article on <ulink
url="&url.articles.contributing;/article.html">Contributing
to FreeBSD</ulink> to learn how to submit code.</para>
<para>And thanks for the thought!</para>
</answer>
</qandaentry>
<qandaentry>
<question id="pnp-initialize">
<para>How are Plug N Play ISA cards detected and
initialized?</para>
</question>
<answer>
<para>By: Frank Durda IV
<email>uhclem@nemesis.lonestar.org</email></para>
<para>In a nutshell, there a few I/O ports that all of the
PnP boards respond to when the host asks if anyone is out
there. So when the PnP probe routine starts, it asks if there
are any PnP boards present, and all the PnP boards respond with
their model # to a I/O read of the same port, so the probe
routine gets a wired-OR <quote>yes</quote> to that question. At
least one bit will be on in that reply. Then the probe code is
able to cause boards with board model IDs (assigned by
Microsoft/Intel) lower than X to go <quote>off-line</quote>. It
then looks to see if any boards are still responding to the
query. If the answer was <literal>0</literal>, then there are
no boards with IDs above X. Now probe asks if there are any
boards below <literal>X</literal>. If so, probe knows there are
boards with a model numbers below X. Probe then asks for boards
greater than X-(limit/4) to go off-line. If repeats the query.
By repeating this semi-binary search of IDs-in-range enough
times, the probing code will eventually identify all PnP boards
present in a given machine with a number of iterations that is
much lower than what 2^64 would take.</para>
<para>The IDs are two 32-bit fields (hence 2&circ;64) + 8 bit
checksum. The first 32 bits are a vendor identifier. They never
come out and say it, but it appears to be assumed that
different types of boards from the same vendor could have
different 32-bit vendor ids. The idea of needing 32 bits just
for unique manufacturers is a bit excessive.</para>
<para>The lower 32 bits are a serial #, Ethernet address,
something that makes this one board unique. The vendor must
never produce a second board that has the same lower 32 bits
unless the upper 32 bits are also different. So you can have
multiple boards of the same type in the machine and the full 64
bits will still be unique.</para>
<para>The 32 bit groups can never be all zero. This allows the
wired-OR to show non-zero bits during the initial binary
search.</para>
<para>Once the system has identified all the board IDs present,
it will reactivate each board, one at a time (via the same I/O
ports), and find out what resources the given board needs, what
interrupt choices are available, etc. A scan is made over all
the boards to collect this information.</para>
<para>This info is then combined with info from any ECU files
on the hard disk or wired into the MLB BIOS. The ECU and BIOS
PnP support for hardware on the MLB is usually synthetic, and
the peripherals do not really do genuine PnP. However by
examining the BIOS info plus the ECU info, the probe routines
can cause the devices that are PnP to avoid those devices the
probe code cannot relocate.</para>
<para>Then the PnP devices are visited once more and given
their I/O, DMA, IRQ and Memory-map address assignments. The
devices will then appear at those locations and remain there
until the next reboot, although there is nothing that says you
cannot move them around whenever you want.</para>
<para>There is a lot of oversimplification above, but you
should get the general idea.</para>
<para>Microsoft took over some of the primary printer status
ports to do PnP, on the logic that no boards decoded those
addresses for the opposing I/O cycles. I found a genuine IBM
printer board that did decode writes of the status port during
the early PnP proposal review period, but MS said
<quote>tough</quote>. So they do a write to the printer status
port for setting addresses, plus that use that address +
<literal>0x800</literal>, and a third I/O port for reading that
can be located anywhere between <literal>0x200</literal> and
<literal>0x3ff</literal>.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="major-numbers">
<para>Can you assign a major number for a device driver I have
written?</para>
</question>
<answer>
<para>&os.current; after February 2003 has a facility for
dynamically and automatically allocating major numbers for
device drivers at runtime. This mechanism is highly
preferred to the older procedure of statically allocating
device numbers. Some comments on this subject can be
found in <filename>src/sys/conf/majors</filename>.</para>
<para>If you are forced for some reason to use a static
major number, the procedure for obtaining one depends on
whether or not you plan on making the driver publicly
available. If you do, then please send us a copy of the
driver source code, plus the appropriate modifications to
<filename>files.i386</filename>, a sample configuration
file entry, and the appropriate &man.MAKEDEV.8; code to
create any special files your device uses. If you do not,
or are unable to because of licensing restrictions, then
character major number 32 and block major number 8 have
been reserved specifically for this purpose; please use
them. In any case, we would appreciate hearing about your
driver on the &a.hackers;.</para>
</answer>
</qandaentry>
<qandaentry>
<question id="alternate-directory-layout">
<para>What about alternative layout policies for
directories?</para>
</question>
<answer>
<para>In answer to the question of alternative layout policies
for directories, the scheme that is currently in use is
unchanged from what I wrote in 1983. I wrote that policy for
the original fast filesystem, and never revisited it. It works
well at keeping cylinder groups from filling up. As several of
you have noted, it works poorly for find. Most filesystems are
created from archives that were created by a depth first search
(aka ftw). These directories end up being striped across the
cylinder groups thus creating a worst possible scenario for
future depth first searches. If one knew the total number of
directories to be created, the solution would be to create
(total / fs_ncg) per cylinder group before moving on.
Obviously, one would have to create some heuristic to guess at
this number. Even using a small fixed number like say 10 would
make an order of magnitude improvement. To differentiate
restores from normal operation (when the current algorithm is
probably more sensible), you could use the clustering of up to
10 if they were all done within a ten second window. Anyway, my
conclusion is that this is an area ripe for
experimentation.</para>
<para>Kirk McKusick, September 1998</para>
</answer>
</qandaentry>
<qandaentry>
<question id="kernel-panic-troubleshooting">
<para>How can I make the most of the data I see when my kernel
panics?</para>
</question>
<answer>
<para><emphasis>[This section was extracted from a mail
written by &a.wpaul; on the freebsd-current
<link linkend="mailing">mailing list</link> by &a.des;, who
fixed a few typos and added the bracketed comments]
</emphasis></para>
<programlisting>From: Bill Paul &lt;wpaul@skynet.ctr.columbia.edu&gt;
Subject: Re: the fs fun never stops
To: Ben Rosengart
Date: Sun, 20 Sep 1998 15:22:50 -0400 (EDT)
Cc: current@FreeBSD.org</programlisting>
<para><emphasis>Ben Rosengart posted the following
panic message]</emphasis></para>
<programlisting>&gt; Fatal trap 12: page fault while in kernel mode
&gt; fault virtual address = 0x40
&gt; fault code = supervisor read, page not present
&gt; instruction pointer = 0x8:0xf014a7e5
^^^^^^^^^^
&gt; stack pointer = 0x10:0xf4ed6f24
&gt; frame pointer = 0x10:0xf4ed6f28
&gt; code segment = base 0x0, limit 0xfffff, type 0x1b
&gt; = DPL 0, pres 1, def32 1, gran 1
&gt; processor eflags = interrupt enabled, resume, IOPL = 0
&gt; current process = 80 (mount)
&gt; interrupt mask =
&gt; trap number = 12
&gt; panic: page fault</programlisting>
<para>[When] you see a message like this, it is not enough to just
reproduce it and send it in. The instruction pointer value that
I highlighted up there is important; unfortunately, it is also
configuration dependent. In other words, the value varies
depending on the exact kernel image that you are using. If
you are using a GENERIC kernel image from one of the snapshots,
then it is possible for somebody else to track down the
offending function, but if you are running a custom kernel then
only <emphasis>you</emphasis> can tell us where the fault
occurred.</para>
<para>What you should do is this:</para>
<procedure>
<step>
<para>Write down the instruction pointer value. Note that
the <literal>0x8:</literal> part at the beginning is not
significant in this case: it is the
<literal>0xf0xxxxxx</literal> part that we want.</para>
</step>
<step>
<para>When the system reboots, do the following:
<screen>&prompt.user; <userinput>nm -n /kernel.that.caused.the.panic | grep f0xxxxxx</userinput></screen>
where <literal>f0xxxxxx</literal> is the instruction
pointer value. The odds are you will not get an exact
match since the symbols in the kernel symbol table are
for the entry points of functions and the instruction
pointer address will be somewhere inside a function, not
at the start. If you do not get an exact match, omit the
last digit from the instruction pointer value and try
again, i.e.:
<screen>&prompt.user; <userinput>nm -n /kernel.that.caused.the.panic | grep f0xxxxx</userinput></screen>
If that does not yield any results, chop off another
digit. Repeat until you get some sort of output. The
result will be a possible list of functions which caused
the panic. This is a less than exact mechanism for
tracking down the point of failure, but it is better than
nothing.</para>
</step>
</procedure>
<para>I see people constantly show panic messages like this
but rarely do I see someone take the time to match up the
instruction pointer with a function in the kernel symbol
table.</para>
<para>The best way to track down the cause of a panic is by
capturing a crash dump, then using &man.gdb.1; to generate
a stack trace on the crash dump.</para>
<para>In any case, the method I normally use is this:</para>
<procedure>
<step>
<para>Set up a kernel config file, optionally adding
<literal>options DDB</literal> if you think you need
the kernel debugger for something. (I use this mainly
for setting breakpoints if I suspect an infinite loop
condition of some kind.)</para>
</step>
<step>
<para>Use <command>config -g
<replaceable>KERNELCONFIG</replaceable></command> to set
up the build directory.</para>
</step>
<step>
<para><command>cd /sys/compile/
<replaceable>KERNELCONFIG</replaceable>; make
</command></para>
</step>
<step>
<para>Wait for kernel to finish compiling.</para>
</step>
<step>
<para><command>make install</command></para>
</step>
<step>
<para>reboot</para>
</step>
</procedure>
<para>The &man.make.1; process will have built two kernels.
<filename>kernel</filename> and
<filename>kernel.debug</filename>.
<filename>kernel</filename> was installed as
<filename>/kernel</filename>, while
<filename>kernel.debug</filename> can be used as the
source of debugging symbols for &man.gdb.1;.</para>
<para>To make sure you capture a crash dump, you need edit
<filename>/etc/rc.conf</filename> and set
<literal>dumpdev</literal> to point to your swap
partition. This will cause the &man.rc.8; scripts to use
the &man.dumpon.8; command to enable crash dumps. You can
also run &man.dumpon.8; manually. After a panic, the
crash dump can be recovered using &man.savecore.8;; if
<literal>dumpdev</literal> is set in
<filename>/etc/rc.conf</filename>, the &man.rc.8; scripts
will run &man.savecore.8; automatically and put the crash
dump in <filename>/var/crash</filename>.</para>
<note>
<para>FreeBSD crash dumps are usually the same size as the
physical RAM size of your machine. That is, if you have
64MB of RAM, you will get a 64MB crash dump. Therefore you
must make sure there is enough space in
<filename>/var/crash</filename> to hold the dump.
Alternatively, you run &man.savecore.8;
manually and have it recover the crash dump to another
directory where you have more room. It is possible to limit
the size of the crash dump by using <literal>options
MAXMEM=(foo)</literal> to set the amount of memory the
kernel will use to something a little more sensible. For
example, if you have 128MB of RAM, you can limit the
kernel's memory usage to 16MB so that your crash dump size
will be 16MB instead of 128MB.</para>
</note>
<para>Once you have recovered the crash dump, you can get a
stack trace with &man.gdb.1; as follows:</para>
<screen>&prompt.user; <userinput>gdb -k /sys/compile/KERNELCONFIG/kernel.debug /var/crash/vmcore.0</userinput>
<prompt>(gdb)</prompt> <userinput>where</userinput></screen>
<para>Note that there may be several screens worth of
information; ideally you should use
&man.script.1; to capture all of them. Using the
unstripped kernel image with all the debug symbols should show
the exact line of kernel source code where the panic occurred.
Usually you have to read the stack trace from the bottom up in
order to trace the exact sequence of events that lead to the
crash. You can also use &man.gdb.1; to print out
the contents of various variables or structures in order to
examine the system state at the time of the crash.</para>
<para>Now, if you are really insane and have a second computer,
you can also configure &man.gdb.1; to do remote
debugging such that you can use &man.gdb.1; on
one system to debug the kernel on another system, including
setting breakpoints, single-stepping through the kernel code,
just like you can do with a normal user-mode program. I have not
played with this yet as I do not often have the chance to set up
two machines side by side for debugging purposes.</para>
<para><emphasis>[Bill adds: "I forgot to mention one thing: if
you have DDB enabled and the kernel drops into the debugger,
you can force a panic (and a crash dump) just by typing 'panic'
at the ddb prompt. It may stop in the debugger again during the
panic phase. If it does, type 'continue' and it will finish the
crash dump." -ed]</emphasis></para>
</answer>
</qandaentry>
<qandaentry>
<question id="dlsym-failure">
<para>Why has dlsym() stopped working for ELF executables?</para>
</question>
<answer>
<para>The ELF toolchain does not, by default, make the symbols
defined in an executable visible to the dynamic linker.
Consequently <function>dlsym()</function> searches on handles
obtained from calls to <function>dlopen(NULL,
flags)</function> will fail to find such symbols.</para>
<para>If you want to search, using
<function>dlsym()</function>, for symbols present in the
main executable of a process, you need to link the
executable using the <option>-export-dynamic</option>
option to the ELF linker (&man.ld.1;).</para>
</answer>
</qandaentry>
<qandaentry>
<question id="change-kernel-address-space">
<para>How can I increase or reduce the kernel address space?</para>
</question>
<answer>
<para>By default, the kernel address space is 256 MB on
FreeBSD 3.X and 1 GB on FreeBSD 4.X. If you run a
network-intensive server (e.g. a large FTP or HTTP server),
you might find that 256 MB is not enough.</para>
<para>So how do you increase the address space? There are two
aspects to this. First, you need to tell the kernel to reserve
a larger portion of the address space for itself. Second, since
the kernel is loaded at the top of the address space, you need
to lower the load address so it does not bump its head against
the ceiling.</para>
<para>The first goal is achieved by increasing the value of
<literal>NKPDE</literal> in
<filename>src/sys/i386/include/pmap.h</filename>. Here is what
it looks like for a 1 GB address space:</para>
<programlisting>#ifndef NKPDE
#ifdef SMP
#define NKPDE 254 /* addressable number of page tables/pde's */
#else
#define NKPDE 255 /* addressable number of page tables/pde's */
#endif /* SMP */
#endif</programlisting>
<para>To find the correct value of <literal>NKPDE</literal>,
divide the desired address space size (in megabytes) by four,
then subtract one for UP and two for SMP.</para>
<para>To achieve the second goal, you need to compute the
correct load address: simply subtract the address space size
(in bytes) from 0x100100000; the result is 0xc0100000 for a 1
GB address space. Set <symbol>LOAD_ADDRESS</symbol> in
<filename>src/sys/i386/conf/Makefile.i386</filename> to that
value; then set the location counter in the beginning of the
section listing in
<filename>src/sys/i386/conf/kernel.script</filename> to the
same value, as follows:</para>
<programlisting>OUTPUT_FORMAT("elf32-i386", "elf32-i386", "elf32-i386")
OUTPUT_ARCH(i386)
ENTRY(btext)
SEARCH_DIR(/usr/lib); SEARCH_DIR(/usr/obj/elf/home/src/tmp/usr/i386-unknown-freebsdelf/lib);
SECTIONS
{
/* Read-only sections, merged into text segment: */
. = 0xc0100000 + SIZEOF_HEADERS;
.interp : { *(.interp) }</programlisting>
<para>Then reconfig and rebuild your kernel. You will
probably have problems with &man.ps.1; &man.top.1; and the
like; <command>make world</command> should take care of it
(or a manual rebuild of <filename>libkvm</filename>,
&man.ps.1; and &man.top.1; after copying the patched
<filename>pmap.h</filename> to
<filename>/usr/include/vm/</filename>.</para>
<para>NOTE: the size of the kernel address space must be a
multiple of four megabytes.</para>
<para>[&a.dg; adds: <emphasis>I think the kernel address space
needs to be a power of two, but I am not certain about that. The
old(er) boot code used to monkey with the high order address bits
and I think expected at least 256MB
granularity.]</emphasis></para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter id="acknowledgments">
<title>Acknowledgments</title>
<blockquote>
<attribution>FreeBSD Core Team</attribution>
<para>If you see a problem with this FAQ, or wish to submit an
entry, please mail the &a.doc;. We appreciate your feedback,
and cannot make this a better FAQ without your help!</para>
</blockquote>
<variablelist>
<varlistentry>
<term>&a.jkh;</term>
<listitem>
<para>Occasional fits of FAQ-reshuffling and updating.</para>
</listitem>
</varlistentry>
<varlistentry>
<term>&a.dwhite;</term>
<listitem>
<para>Services above and beyond the call of duty on
freebsd-questions</para>
</listitem>
</varlistentry>
<varlistentry>
<term>&a.joerg;</term>
<listitem>
<para>Services above and beyond the call of duty on
Usenet</para>
</listitem>
</varlistentry>
<varlistentry>
<term>&a.wollman;</term>
<listitem>
<para>Networking and formatting</para>
</listitem>
</varlistentry>
<varlistentry>
<term>Jim Lowe</term>
<listitem>
<para>Multicast information</para>
</listitem>
</varlistentry>
<varlistentry>
<term>&a.pds;</term>
<listitem>
<para>FreeBSD FAQ typing machine slavey</para>
</listitem>
</varlistentry>
<varlistentry>
<term>The FreeBSD Team</term>
<listitem>
<para>Kvetching, moaning, submitting data</para>
</listitem>
</varlistentry>
</variablelist>
<para>And to any others we have forgotten, apologies and heartfelt
thanks!</para>
</chapter>
&bibliography;
</book>
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