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<!DOCTYPE BOOK PUBLIC "-//FreeBSD//DTD DocBook V3.1-Based Extension//EN">
<book>
<bookinfo>
<title>Frequently Asked Questions for FreeBSD 2.X</title>
<authorgroup>
<author>
<surname>The FreeBSD Documentation Project</surname>
</author>
</authorgroup>
<pubdate>$Date: 1999-08-30 05:33:19 $</pubdate>
<abstract><para> This is the FAQ for FreeBSD systems version 2.X All entries are
assumed to be relevant to FreeBSD 2.0.5 and later, unless otherwise noted.
Any entries with a &lt;XXX&gt; are under construction.
If you are interested in helping with this project, send
email to the the FreeBSD documentation project mailing list <ulink URL="mailto:freebsd-doc@FreeBSD.org">&lt;freebsd-doc@FreeBSD.org&gt;</ulink>.
The latest version of this document is always available from the <ulink URL="http://www.FreeBSD.org/">FreeBSD World Wide Web server</ulink>.
It may also be downloaded in <ulink URL="FAQ.latin1">plain text</ulink>, <ulink URL="FAQ.ps">postscript</ulink>, <ulink URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/doc/FAQ.pdf">PDF</ulink>
or <ulink URL="FAQ-html.tar.gz">HTML</ulink> with HTTP or gzip'd from the <ulink URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/doc">FreeBSD FTP server</ulink>. You may also want to <ulink URL="http://www.FreeBSD.org/search/search.html">Search the FAQ</ulink>. </para></abstract>
</bookinfo>
<preface id="preface">
<title>Preface</title>
<para>Welcome to the FreeBSD 2.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 <ulink URL="mailto:FAQ@FreeBSD.org">FAQ maintainer</ulink>.</para>
<qandaset><qandaentry><question>
<para>What is FreeBSD?</para></question><answer>
<para>Briefly, FreeBSD 2.X is a UN*X-like operating system based on
U.C. Berkeley's 4.4BSD-lite release for the i386 platform. It is
also based indirectly on William Jolitz's port of U.C. Berkeley's
Net/2 to the i386, known as 386BSD, 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="http://www.FreeBSD.org/">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. See some of them in the
<ulink URL="../gallery/gallery.html">FreeBSD Gallery.</ulink></para>
<para>For more detailed information on FreeBSD, please see the
<ulink URL="../handbook/index.html">FreeBSD Handbook.</ulink></para>
</answer></qandaentry>
<qandaentry><question>
<para>What are the goals of FreeBSD?</para></question><answer>
<para>The goals of the FreeBSD Project are 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're definitely not prepared to insist on it. We believe
that our first and foremost "mission" 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 GNU General
Public License (GPL) or GNU Library General Public License (LGPL)
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 BSD copyright whenever
possible.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Why is it called FreeBSD?</para></question><answer>
<para>
<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 and/or bug fix is free to submit
their code and have it added to the source tree (subject to
one or two obvious provisos).</para>
</listitem>
</itemizedlist>
</para>
<para>For those of our readers whose first language is not English, it
may be worth pointing out that the word ``free'' is being used in two
ways here, one meaning ``at no cost'', the other meaning ``you can do
whatever you like''. Apart from one or two things you <emphasis remap=tt>cannot</emphasis>
do with the FreeBSD code, for example pretending you wrote it, you
really can do whatever you like with it.</para>
</answer></qandaentry>
<qandaentry><question>
<para>What is the latest version of FreeBSD?</para></question><answer>
<para>Version <ulink URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/i386/3.2-RELEASE/">3.2</ulink> is the latest <emphasis>stable</emphasis> version; it was released
in May, 1999. This is also the latest <emphasis>release</emphasis> version.</para>
<para>Briefly explained, <emphasis>-stable</emphasis> is aimed at the ISP or other
corporate user who wants stability and a low change count over
the wizzy new features of the latest <emphasis>-current</emphasis> snapshot.
Releases can come from either "branch," but you should only use
<emphasis>-current</emphasis> if you're sure that you're prepared for its
increased volatility (relative to <emphasis>-stable</emphasis>, that is).</para>
<para>Releases are only made <xref linkend="release-freq" remap="every few months">. While many people stay more up-to-date with the
FreeBSD sources (see the questions on <xref linkend="current" remap="FreeBSD-current"> and <xref linkend="stable" remap="FreeBSD-stable">) than that, doing so is more of a
commitment, as the sources are a moving target.</para>
</answer></qandaentry>
<qandaentry><question
id="current">
<para>What is FreeBSD-current?</para></question><answer>
<para><ulink URL="../handbook/cutting-edge.html#CURRENT">FreeBSD-current</ulink> is the
development version of the operating system, which will in due
course become 4.0-RELEASE. As such, it is really only of interest
to developers working on the system and die-hard hobbyists.
See the <ulink URL="../handbook/cutting-edge.html#CURRENT">relevant section</ulink>
in the <ulink URL="../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 ``glitches''. Questions
such as ``make world produces some error about groups'' on the
-current mailing list are sometimes treated with contempt.</para>
<para>Every now and again, a <ulink URL="../releases/snapshots.html">snapshot</ulink> release is also made of this -current development
code, CDROM distributions of the occasional snapshot even now being
made available. The goals behind each snapshot release are:</para>
<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 but who don't
have the time and/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 any new features in need of testing have the
greatest possible number of potential testers.</para>
</listitem>
</itemizedlist>
</para>
<para>No claims are made that any snapshot can be considered
``production quality'' for any purpose. For stability
and tested mettle, you will have to stick to full releases.</para>
<para>Snapshot releases are directly available from <ulink URL="ftp://current.FreeBSD.org/pub/FreeBSD/">ftp://current.FreeBSD.org/pub/FreeBSD/</ulink> and are generated,
on the average, once a day for both the 4.0-current and 3.0-stable
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, we decided to branch FreeBSD
development into two parts. One branch was named <ulink URL="../handbook/stable.html">-stable</ulink>, with the
intention that only well-tested bug fixes and small incremental
enhancements would be made to it (for Internet Service Providers
and other commercial enterprises for whom sudden shifts or
experimental features are quite undesirable). The other branch was
<ulink URL="../handbook/cutting-edge.html#CURRENT">-current</ulink>, which
essentially has been one unbroken line leading towards 4.0-RELEASE
(and beyond) since 2.0 was released. If a little ASCII art would
help, this is how it looks:</para>
<para>
<literallayout> 2.0
|
|
| [2.1-stable]
*BRANCH* 2.0.5 -&gt; 2.1 -&gt; 2.1.5 -&gt; 2.1.6 -&gt; 2.1.7.1 [2.1-stable ends]
| (Mar 1997)
|
|
| [2.2-stable]
*BRANCH* 2.2.1 -&gt; 2.2.2-RELEASE -&gt; 2.2.5 -&gt; 2.2.6 -&gt; 2.2.7 -&gt; 2.2.8 [end]
| (Mar 1997) (Oct 97) (Apr 98) (Jul 98) (Dec 98)
|
|
3.0-SNAPs (started Q1 1997)
|
|
3.0.0-RELEASE (Oct 1998)
|
| [3.0-stable]
*BRANCH* 3.1 (Feb 1999) -&gt; 3.2 -&gt; ... future 3.x releases ...
| (May 1999)
|
\|/
+
[4.0-current continues]</literallayout>
</para>
<para>The -current branch is slowly progressing towards 4.0 and beyond,
the previous 2.2-stable branch having just retired with the release
of 2.2.8. 3.0-stable has now replaced it, the next release coming
up with 3.3 in Q3 1999. 4.0-current is now the "current branch",
with the first 4.0 releases appearing in Q1 2000.</para>
</answer></qandaentry>
<qandaentry>
<question id="release-freq"><para>When are FreeBSD releases made?</para></question><answer>
<para>As a general principle, the FreeBSD core team only release a new
version of FreeBSD when they believe that there are sufficient new
features and/or bug fixes to justify one, and are satisfied that the
changes made have settled down sufficiently to avoid compromising the
stability of the release. Many users regard this caution as one of
the best things about FreeBSD, although it can be a little
frustrating when waiting for all the latest goodies to become
available...</para>
<para>Releases are made about every 4 months on average.</para>
<para>For people needing (or wanting) a little more excitement, there are
SNAPs released more frequently, particularly during the month or so
leading up to a release.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Is FreeBSD only available for PCs ?</para></question><answer>
<para>FreeBSD 3.x currently runs on the <ulink URL="../alpha/alpha.html">DEC Alpha</ulink> as well as the
x86 architecture. Some interest has also been expressed in a
SPARC port, but details on this project are not yet clear.</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>
<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="../handbook/staff.html#STAFF-CORE">core team</ulink> of some 15 people. There is a much larger team of
over 150 <ulink URL="../handbook/staff-committers.html">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
<xref linkend="mailing" remap="mailing lists">, 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>
<para>
<itemizedlist>
<listitem>
<para>For the current 2.2-stable release, 2.2.8R, see the
<ulink URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/releases/2.2.8-RELEASE/">2.2.8-RELEASE</ulink> directory.
</para>
</listitem>
<listitem>
<para>For the current 3.0-stable release, 3.0-RELEASE, see the
<ulink URL="ftp://current.FreeBSD.org/pub/FreeBSD/releases/3.0-RELEASE/">3.0-RELEASE</ulink> directory.
</para>
</listitem>
<listitem>
<para><ulink URL="ftp://releng22.FreeBSD.org/pub/FreeBSD/">2.2 Snapshot</ulink> releases are made once a day along the
RELENG_2_2 branch (post 2.2.8) as it slowly winds down in
maintenance mode. The RELENG_2_2 branch is currently being carefully
maintained by the legacy support folks and no changes other than
those strictly necessary for security or reliability enhancements
are now made.
</para>
</listitem>
<listitem>
<para><ulink URL="ftp://releng30.FreeBSD.org/pub/FreeBSD/">3.0 Snapshot</ulink> releases are also made once a day along the
RELENG_3 branch (post 3.0-release) as it continues on its way
towards 3.2-RELEASE.
</para>
</listitem>
<listitem>
<para><ulink URL="ftp://current.FreeBSD.org/pub/FreeBSD/">4.0 Snapshot</ulink> releases are made once a day for the
<xref linkend="current" remap="-current"> branch, these being of service
purely to bleeding-edge testers and developers.</para>
</listitem>
</itemizedlist>
</para>
<para>FreeBSD is also available via CDROM, from the following place(s):</para>
<para>Walnut Creek CDROM<!-- <br> -->
4041 Pike Lane, Suite F<!-- <br> -->
Concord, CA 94520 USA<!-- <br> -->
Orders: +1 800 786-9907<!-- <br> -->
Questions: +1 925 674-0783<!-- <br> -->
FAX: +1 925 674-0821<!-- <br> -->
email: <ulink URL="mailto:orders@cdrom.com">WC Orders address</ulink><!-- <br> -->
WWW: <ulink URL="http://www.cdrom.com/">WC Home page</ulink><!-- <br> --></para>
<para>In Australia, you may find it at:</para>
<para>Advanced Multimedia Distributors<!-- <br> -->
Factory 1/1 Ovata Drive<!-- <br> -->
Tullamarine, Melbourne<!-- <br> -->
Victoria<!-- <br> -->
Australia<!-- <br> -->
Voice: +61 3 9338 6777<!-- <br> --></para>
<para>CDROM Support BBS<!-- <br> -->
17 Irvine St<!-- <br> -->
Peppermint Grove WA 6011<!-- <br> -->
Voice: +61 9 385-3793<!-- <br> -->
Fax: +61 9 385-2360<!-- <br> --></para>
<para>And in the UK:</para>
<para>The Public Domain &amp; Shareware Library<!-- <br> -->
Winscombe House, Beacon Rd<!-- <br> -->
Crowborough<!-- <br> -->
Sussex. TN6 1UL<!-- <br> -->
Voice: +44 1892 663-298<!-- <br> -->
Fax: +44 1892 667-473<!-- <br> --></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="../handbook/eresources.html#ERESOURCES-MAIL">Handbook entry on mailing-lists.</ulink></para>
</answer></qandaentry>
<qandaentry><question>
<para>Where do I find the FreeBSD Y2K info?</para></question><answer>
<para>You can find full information in the <ulink URL="http://www.FreeBSD.org/y2kbug.html">FreeBSD Y2K page.</ulink></para>
</answer></qandaentry>
<qandaentry><question>
<para>What FreeBSD news groups are available?</para></question><answer>
<para>You can find full information in the<ulink URL="../handbook/eresources-news.html">Handbook entry on newsgroups.</ulink></para>
</answer></qandaentry>
<qandaentry><question>
<para> Are there FreeBSD IRC (Internet Relay Chat) channels?
</para></question><answer>
<para>Yes, most major IRC networks host a FreeBSD chat
channel:</para>
<para>
<itemizedlist>
<listitem>
<para>Channel <emphasis remap=tt>#FreeBSD</emphasis> on EFNet is
a FreeBSD forum, but don't go there for tech support
or to try and get folks there to help you avoid the pain of
reading man 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 <filename>irc.chat.org</filename>.
</para>
</listitem>
<listitem>
<para>Channel <emphasis remap=tt>#FreeBSD</emphasis> on DALNET
is available at <filename>irc.dal.net</filename> in the US and
<filename>irc.eu.dal.net</filename> in Europe.
</para>
</listitem>
<listitem>
<para>Channel <emphasis remap=tt>#FreeBSD</emphasis> on UNDERNET is
available at <filename>us.undernet.org</filename> in the US and
<filename>eu.undernet.org</filename> in Europe. Same provisions as
for EFNET apply - either don't ask questions or learn to
ask amazingly politely if you want help. It's a chat channel,
not a help channel.
</para>
</listitem>
<listitem>
<para>Finally, you can also join <emphasis remap=tt>#FreeBSD</emphasis> on BSDNET,
a smaller BSD only chat network, at <filename>irc.FreeBSD.org</filename>.
This network attempts to do more tech support and not be
as anarchistic as EFNET, UNDERNET or DALNET, but it's also
nowhere near as popular as a result. Why not volunteer to
answer FreeBSD questions on BSDNET today?</para>
</listitem>
</itemizedlist>
</para>
<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 *all* types
of IRC traffic, if you're easily offended or can't deal with lots
of young people (and more than a few older ones) doing the verbal
equivalent of jello wrestling, don't even bother with it.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Books on FreeBSD</para></question><answer>
<para>There is a FreeBSD Documentation Project which you may contact (or
even better, join) on the <emphasis remap=tt>doc</emphasis> mailing list:
<ulink URL="mailto:freebsd-doc@FreeBSD.org">&lt;freebsd-doc@FreeBSD.org&gt;</ulink>.
This list is for discussion of the FreeBSD documentation. For
actual questions about FreeBSD, there is the <emphasis remap=tt>questions</emphasis>
mailing list:
<ulink URL="mailto:freebsd-questions@FreeBSD.org">&lt;freebsd-questions@FreeBSD.org&gt;</ulink>.</para>
<para>A FreeBSD ``handbook'' is available, and can be found as:
<ulink URL="../handbook/index.html">the FreeBSD Handbook</ulink>.
Note that this is a work in progress, and so parts may be incomplete.</para>
<para>The definitive printed guide on FreeBSD is ``The Complete FreeBSD'',
written by Greg Lehey and published by Walnut Creek CDROM Books. Now
in its second edition, the book contains 1,750 pages of install &amp;
system administration guidance, program setup help, and manual pages.
The book (and current FreeBSD release) can be ordered from
<ulink URL="http://www.cdrom.com">Walnut Creek</ulink>,
<ulink URL="http://www.cheapbytes.com">CheapBytes</ulink>, or at your
favorite bookstore. The ISBN is 1-57176-227-2.</para>
<para>However, as FreeBSD 2.2.X is based upon Berkeley 4.4BSD-Lite2, most
of the 4.4BSD manuals are applicable to FreeBSD 2.2.X. O'Reilly
and Associates publishes these manuals:</para>
<para>
<itemizedlist>
<listitem>
<para>4.4BSD System Manager's Manual <!-- <br> -->
By Computer Systems Research Group, UC Berkeley <!-- <br> -->
1st Edition June 1994, 804 pages <!-- <br> -->
<ulink URL="http://www.amazon.com/exec/obidos/ASIN/1-56592-080-5">ISBN</ulink>: 1-56592-080-5 <!-- <br> -->
</para>
</listitem>
<listitem>
<para>4.4BSD User's Reference Manual <!-- <br> -->
By Computer Systems Research Group, UC Berkeley <!-- <br> -->
1st Edition June 1994, 905 pages <!-- <br> -->
<ulink URL="http://www.amazon.com/exec/obidos/ASIN/1-56592-075-9">ISBN</ulink>: 1-56592-075-9 <!-- <br> -->
</para>
</listitem>
<listitem>
<para>4.4BSD User's Supplementary Documents <!-- <br> -->
By Computer Systems Research Group, UC Berkeley <!-- <br> -->
1st Edition July 1994, 712 pages <!-- <br> -->
<ulink URL="http://www.amazon.com/exec/obidos/ASIN/1-56592-076-7">ISBN</ulink>: 1-56592-076-7 <!-- <br> -->
</para>
</listitem>
<listitem>
<para>4.4BSD Programmer's Reference Manual <!-- <br> -->
By Computer Systems Research Group, UC Berkeley <!-- <br> -->
1st Edition June 1994, 886 pages <!-- <br> -->
<ulink URL="http://www.amazon.com/exec/obidos/ASIN/1-56592-078-3">ISBN</ulink>: 1-56592-078-3 <!-- <br> -->
</para>
</listitem>
<listitem>
<para>4.4BSD Programmer's Supplementary Documents <!-- <br> -->
By Computer Systems Research Group, UC Berkeley <!-- <br> -->
1st Edition July 1994, 596 pages <!-- <br> -->
<ulink URL="http://www.amazon.com/exec/obidos/ASIN/1-56592-079-1">ISBN</ulink>: 1-56592-079-1 <!-- <br> --></para>
</listitem>
</itemizedlist>
</para>
<para>A description of these can be found via WWW as:</para>
<para><ulink URL="http://gnn.com/gnn/bus/ora/category/bsd.html">4.4BSD books description</ulink>. Due to poor sales, however, these
manuals may be hard to get a hold of.</para>
<para>For a more in-depth look at the 4.4BSD kernel organization,
you can't go wrong with:</para>
<para>McKusick, Marshall Kirk, Keith Bostic, Michael J Karels,
and John Quarterman.<!-- <br> --></para>
<para><emphasis>The Design and Implementation of the 4.4BSD Operating
System</emphasis>. Reading, Mass. : Addison-Wesley, 1996.<!-- <br> -->
<ulink URL="http://www.amazon.com/exec/obidos/ASIN/0-201-54979-4">ISBN</ulink> 0-201-54979-4<!-- <br> --></para>
<para>A good book on system administration is:</para>
<para>Evi Nemeth, Garth Snyder, Scott Seebass &amp; Trent R. Hein,<!-- <br> -->
``Unix System Administration Handbook'', Prentice-Hall, 1995<!-- <br> -->
<ulink URL="http://www.amazon.com/exec/obidos/ASIN/0-13-151051-7">ISBN</ulink>: 0-13-151051-7<!-- <br> --></para>
<para><acronym>NOTE</acronym> make sure you get the second edition, with a red cover,
instead of the first edition.</para>
<para>This book covers the basics, as well as TCP/IP, DNS, NFS,
SLIP/PPP, sendmail, INN/NNTP, printing, etc.. It's expensive
(approx. US&#36;45-&#36;55), but worth it. It also
includes a CDROM with the sources for various tools; most of
these, however, are also on the FreeBSD 2.2.6R CDROM (and the
FreeBSD CDROM often has newer versions).</para>
</answer></qandaentry>
<qandaentry><question>
<para>How do I access your Problem Report database?</para></question><answer>
<para>The Problem Report database of all open user change requests
may be queried (or submitted to) by using our web-based PR
<ulink URL="http://www.FreeBSD.org/send-pr.html">submission</ulink>
and <ulink URL="http://www.FreeBSD.org/cgi/query-pr-summary.cgi">query</ulink> interfaces. The <command>send-pr(1)</command> command
can also be used to submit problem reports and change requests via
electronic mail.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Where can I get ASCII/PostScript versions of the FAQ?</para></question><answer>
<para>The up-to-date FAQ is available from the FreeBSD Web Server or any
mirror as PostScript and plain text (7 bit ASCII and 8-bit Latin1).</para>
<para>As PostScript (about 370KB):
<itemizedlist>
<listitem>
<para><ulink URL="http://www.FreeBSD.org/FAQ/FAQ.ps">http://www.FreeBSD.org/FAQ/FAQ.ps</ulink></para>
</listitem>
</itemizedlist>
</para>
<para>As ASCII text (about 220KB):
<itemizedlist>
<listitem>
<para><ulink URL="http://www.FreeBSD.org/FAQ/FAQ.ascii">http://www.FreeBSD.org/FAQ/FAQ.ascii</ulink></para>
</listitem>
</itemizedlist>
</para>
<para>As ISO 8859-1 text (about 220KB):
<itemizedlist>
<listitem>
<para><ulink URL="http://www.FreeBSD.org/FAQ/FAQ.latin1">http://www.FreeBSD.org/FAQ/FAQ.latin1</ulink></para>
</listitem>
</itemizedlist>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>Where can I get ASCII/PostScript versions of the Handbook?</para></question><answer>
<para>The up-to-date Handbook is available from the FreeBSD Web Server or any
mirror as PostScript and plain text (7 bit ASCII and 8-bit Latin1).</para>
<para>As PostScript (about 1.7MB):
<itemizedlist>
<listitem>
<para><ulink URL="http://www.FreeBSD.org/handbook/handbook.ps">http://www.FreeBSD.org/handbook/handbook.ps</ulink></para>
</listitem>
</itemizedlist>
</para>
<para>As ASCII text (about 1080KB):
<itemizedlist>
<listitem>
<para><ulink URL="http://www.FreeBSD.org/handbook/handbook.ascii">http://www.FreeBSD.org/handbook/handbook.ascii</ulink></para>
</listitem>
</itemizedlist>
</para>
<para>As ISO 8859-1 text (about 1080KB):
<itemizedlist>
<listitem>
<para><ulink URL="http://www.FreeBSD.org/handbook/handbook.latin1">http://www.FreeBSD.org/handbook/handbook.latin1</ulink></para>
</listitem>
</itemizedlist>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>The ASCII handbook isn't plain text!</para></question><answer>
<para>True, the ASCII and Latin1 versions of the FAQ and Handbook aren't
strictly plaintext; they contain underlines and overprints that
assume the output is going directly to a dot matrix printer. If you
need to reformat them to be human-readable, run the file through col:</para>
<para>
<literallayout> $ col -b &lt; inputfile &gt; outputfile
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>I'd like to become a FreeBSD Web mirror!</para></question><answer>
<para>Certainly! There are multiple ways to mirror the Web pages.</para>
<para>
<itemizedlist>
<listitem>
<para>Using CVSUP: You can retrieve the formatted files using CVSUP
from cvsup.FreeBSD.org. Add this line to your cvsup file:
<literallayout>www release=current hostname=/home base=/usr/local/etc/cvsup
prefix=/usr/local/www/data/www.FreeBSD.org delete old use-rel-suffix
</literallayout>
</para>
</listitem>
<listitem>
<para>Using rsync: See <ulink URL="http://www.FreeBSD.org/internal/mirror.html">the mirroring page</ulink> for information.</para>
</listitem>
<listitem>
<para>Using ftp mirror: You can download the FTP server's copy of
the web site using your favorite ftp mirror tool. Simply start at
ftp://ftp.FreeBSD.org/pub/FreeBSD/FreeBSD-current/www.</para>
</listitem>
</itemizedlist>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>I'd like to translate the documentation into Friesian.</para></question><answer>
<para>Well, we can't pay, but we might arrange a free CD or T-shirt and a
Contributor's Handbook entry if you submit a translation of the
documentation.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Other sources of information.</para></question><answer>
<para>The following newsgroups contain pertinent discussion for FreeBSD
users:</para>
<para>
<itemizedlist>
<listitem>
<para><ulink URL="news:comp.unix.bsd.freebsd.announce">comp.unix.bsd.freebsd.announce</ulink> (moderated)
</para>
</listitem>
<listitem>
<para><ulink URL="news:comp.unix.bsd.freebsd.misc">comp.unix.bsd.freebsd.misc</ulink>
</para>
</listitem>
<listitem>
<para><ulink URL="news:comp.unix.bsd.misc">comp.unix.bsd.misc</ulink></para>
</listitem>
</itemizedlist>
</para>
<para>Web resources:</para>
<para>
<itemizedlist>
<listitem>
<para>The <ulink URL="http://www.FreeBSD.org/">FreeBSD Home Page</ulink>.
</para>
</listitem>
<listitem>
<para><anchor id="pao">If you have a laptop, be sure and see
<ulink URL="http://www.jp.FreeBSD.org/PAO/">Tatsumi Hosokawa's Mobile Computing page</ulink> in Japan.
</para>
</listitem>
<listitem>
<para><anchor id="smp">For information on SMP (Symmetric
MultiProcessing), please see the <ulink URL="http://www.FreeBSD.org/~fsmp/SMP/SMP.html">SMP support page</ulink>.
</para>
</listitem>
<listitem>
<para><anchor id="multimedia">For information on FreeBSD multimedia
applications, please see the <ulink URL="http://www.FreeBSD.org/~faulkner/multimedia/mm.html">multimedia</ulink>page. If you're interested specifically in
the <ulink URL="http://www.FreeBSD.org/~ahasty/Bt848.html">Bt848</ulink> video capture chip, then follow that link.</para>
</listitem>
</itemizedlist>
</para>
<para>The FreeBSD handbook also has a fairly complete
<ulink URL="../handbook/bibliography.html">bibliography</ulink>
section which is worth reading if you're looking for actual
books to buy.</para>
</answer></qandaentry></qandaset>
</preface>
<chapter
id="install">
<title>Installation</title>
<qandaset><qandaentry><question>
<para>Which file do I download to get FreeBSD?</para></question><answer>
<para>You generally need just one floppy image, the <filename>floppies/boot.flp</filename> file, which you image-copy onto a 1.44MB floppy and then boot from
in order to download the rest (and the installation will manage your
TCP/IP connection, deal with tapes, CDROMs, floppies, DOS
partitions, whatever's necessary to get the rest of the bits
installed).</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>
<para>
<itemizedlist>
<listitem>
<para> bin/<!-- <br> --></para>
</listitem>
<listitem>
<para> manpages/<!-- <br> --></para>
</listitem>
<listitem>
<para> compat*/<!-- <br> --></para>
</listitem>
<listitem>
<para> doc/ <!-- <br> --></para>
</listitem>
<listitem>
<para> src/ssys.* <!-- <br> --></para>
</listitem>
</itemizedlist>
</para>
<para>Full instructions on this procedure and a little bit more about
installation issues in general can be found in the <ulink URL="../handbook/install.html">Handbook entry on installing FreeBSD.</ulink></para>
</answer></qandaentry>
<qandaentry><question>
<para>Help! The boot floppy image will not fit on a single floppy!
</para></question><answer>
<para>A 3.5 inch (1.44MB) floppy can accomodate 1474560 bytes of data.
The boot image is exactly 1474560 bytes in size.</para>
<para>Common mistakes when preparing the boot floppy are:
<itemizedlist>
<listitem>
<para>Not downloading the floppy image in <emphasis remap=tt>binary</emphasis> mode when
using <acronym>FTP</acronym>.
</para>
<para>Some FTP clients default their transfer mode to <emphasis remap=tt>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 remap=tt>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 <emphasis remap=tt>copy</emphasis> command (or equivalent GUI tool) to
transfer the boot image to floppy.
</para>
<para>Programs like <emphasis remap=tt>copy</emphasis> 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 ``raw'', using the
low-level tools (e.g. <emphasis remap=tt>fdimage</emphasis> or <emphasis remap=tt>rawrite</emphasis>)
described in the <ulink URL="../handbook/install.html">installation guide to FreeBSD</ulink>.</para>
</listitem>
</itemizedlist>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>Where are the instructions for installing FreeBSD?</para></question><answer>
<para>Installation instructions can be found in the
<ulink URL="../handbook/install.html">Handbook entry on installing FreeBSD.</ulink></para>
</answer></qandaentry>
<qandaentry><question>
<para>What do I need in order to run FreeBSD?</para></question><answer>
<para>You'll need a 386 or better PC, with 5 MB or more of RAM and at
least 60 MB of hard disk space. It 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 the section on <xref linkend="hardware" remap="Hardware compatibility"></para>
</answer></qandaentry>
<qandaentry><question>
<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. Newer versions of FreeBSD, like 2.2, need at least 5MB
to install on a new system.</para>
<para>All versions of FreeBSD, including 3.0, will RUN in 4MB of ram, they
just can't 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
always just swap your disk into a system which has &gt;4MB, install onto
it and then swap it back.</para>
<para>There are also situations in which FreeBSD 2.1.7 will not install
in 4 MB. To be exact: it does not install with 640 kB base + 3 MB
extended memory. If your motherboard can remap some of the ``lost''
memory out of the 640kB to 1MB region, then you may still be able
to get FreeBSD 2.1.7 up.</para>
<para>Try to go into your BIOS setup and look for a ``remap'' option.
Enable it. You may also have to disable ROM shadowing.</para>
<para>It may be easier to get 4 more MB just for the install. Build a
custom kernel with only the options you need and then get the 4
MB out again.</para>
<para>You may also install 2.0.5 and then upgrade your system to 2.1.7
with the ``upgrade'' option of the 2.1.7 installation program.</para>
<para>After the installation, if you build a custom kernel, it will run
in 4 MB. Someone has even succeeded in booting with 2 MB (the
system was almost unusable though :-))</para>
</answer></qandaentry>
<qandaentry><question>
<para> How can I make my own custom install floppy?
</para></question><answer>
<para>Currently there's no way to *just* make a custom install floppy.
You have to cut a whole new release, which will include your install
floppy. There's some code in <filename>/usr/src/release/floppies/Makefile</filename>
that's supposed to let you *just* make those floppies, but it's not
really gelled yet.</para>
<para>To make a custom release, follow the instructions <xref linkend="custrel" remap="here">.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Can I have more than one operating system on my PC?</para></question><answer>
<para>Have a look at <ulink URL="../tutorials/multios/multios.html">The multi-OS page.</ulink></para>
</answer></qandaentry>
<qandaentry><question>
<para>Can Windows 95 co-exist with FreeBSD?</para></question><answer>
<para>Install Windows 95 first, after that FreeBSD. FreeBSD's boot
manager will then manage to boot Win95 and FreeBSD. If you
install Windows 95 second, it will boorishly overwrite your
boot manager without even asking. If that happens, see
the next section.</para>
</answer></qandaentry>
<qandaentry><question>
<para> Windows 95 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
two ways:</para>
<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>
<para><emphasis remap=bf>bootinst.exe boot.bin</emphasis></para>
<para></para>
<para>and the boot manager will be reinstalled.</para>
<para></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 "Boot Manager."
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>
</itemizedlist>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>Can I install on a disk with bad blocks?</para></question><answer>
<para>FreeBSD's bad block (the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?bad144">bad144</ulink>
command) handling is still not 100% (to put it charitably) and
it must unfortunately be said that if you've got an IDE or ESDI drive
with lots of bad blocks, then FreeBSD is probably not for you!
That said, it does work on thousands of IDE based systems, so
you'd do well to try it first before simply giving up.</para>
<para>If you have a SCSI drive with bad blocks, see <xref linkend="awre" remap="this answer">.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Strange things happen when I boot the install floppy!</para></question><answer>
<para>If you're 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>
<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 coverdisk that's 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?
(don't 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're using one of these new-fangled operating systems
like Windows95 or Windows NT, did you shut it down and restart
the system in plain, honest DOS? It seems these OS's 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>
<para>There have also been reports of Netscape causing problems when
downloading the boot floppy, so it's probably best to use a different
FTP client if you can.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Help! I can't install from tape!</para></question><answer>
<para>If you are installing 2.1.7R from tape, you must create the tape
using a tar blocksize of 10 (5120 bytes). The default tar
blocksize is 20 (10240 bytes), and tapes created using this
default size cannot be used to install 2.1.7R; with these tapes,
you will get an error that complains about the record size being
too big.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Connect two FreeBSD boxes over a parallel line (PLIP)
</para></question><answer>
<para>Get a laplink cable. Make sure both computer have a kernel
with lpt driver support.</para>
<para>
<literallayout> $ dmesg | grep lp
lpt0 at 0x378-0x37f irq 7 on isa
lpt0: Interrupt-driven port
lp0: TCP/IP capable interface
</literallayout>
</para>
<para>Plug in the laplink cable into the parallel interface.</para>
<para>Configure the network interface parameters for lp0 on both
sites as root. For example, if you want connect the host max
with moritz</para>
<para>
<literallayout> max &lt;-----&gt; moritz
IP Address 10.0.0.1 10.0.0.2
</literallayout>
</para>
<para>on max start
<literallayout> # ifconfig lp0 10.0.0.1 10.0.0.2
</literallayout>
</para>
<para>on moritz start</para>
<para>
<literallayout> # ifconfig lp0 10.0.0.2 10.0.0.1
</literallayout>
</para>
<para>Thats all! Please read also the manpages
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?lp">lp(4)</ulink> and
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?lpt">lpt(4)</ulink>.</para>
<para>You should also add the hosts to /etc/hosts</para>
<para>
<literallayout> 127.0.0.1 localhost.my.domain localhost
10.0.0.1 max.my.domain max
10.0.0.2 moritz.my.domain moritz
</literallayout>
</para>
<para>To check if it works do:</para>
<para>on max:</para>
<para>
<literallayout>$ ifconfig lp0
lp0: flags=8851&lt;UP,POINTOPOINT,RUNNING,SIMPLEX,MULTICAST&gt; mtu 1500
inet 10.0.0.1 --&gt; 10.0.0.2 netmask 0xff000000 </literallayout>
</para>
<para>
<literallayout>$ netstat -r
Routing tables
Internet:
Destination Gateway Flags Refs Use Netif Expire
moritz max UH 4 127592 lp0</literallayout>
</para>
<para>
<literallayout>$ ping -c 4 moritz
PING moritz (10.0.0.2): 56 data bytes
64 bytes from 10.0.0.2: icmp_seq=0 ttl=255 time=2.774 ms
64 bytes from 10.0.0.2: icmp_seq=1 ttl=255 time=2.530 ms
64 bytes from 10.0.0.2: icmp_seq=2 ttl=255 time=2.556 ms
64 bytes from 10.0.0.2: icmp_seq=3 ttl=255 time=2.714 ms
--- moritz ping statistics ---
4 packets transmitted, 4 packets received, 0% packet loss
round-trip min/avg/max/stddev = 2.530/2.643/2.774/0.103 ms</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para> Can I install on my laptop over PLIP (Parallel Line IP)?
</para></question><answer>
<para>Connect the two computers using a Laplink parallel cable to use
this feature:</para>
<para>
<literallayout> +----------------------------------------+
|A-name A-End B-End Descr. Port/Bit |
+----------------------------------------+
|DATA0 2 15 Data 0/0x01 |
|-ERROR 15 2 1/0x08 |
+----------------------------------------+
|DATA1 3 13 Data 0/0x02 |
|+SLCT 13 3 1/0x10 |
+----------------------------------------+
|DATA2 4 12 Data 0/0x04 |
|+PE 12 4 1/0x20 |
+----------------------------------------+
|DATA3 5 10 Strobe 0/0x08 |
|-ACK 10 5 1/0x40 |
+----------------------------------------+
|DATA4 6 11 Data 0/0x10 |
|BUSY 11 6 1/0x80 |
+----------------------------------------+
|GND 18-25 18-25 GND - |
+----------------------------------------+
</literallayout>
</para>
<para>See also <link linkend="pao">this note</link> on the Mobile Computing page.</para>
</answer></qandaentry>
<qandaentry><question
id="geometry">
<para> Which geometry should I use for a disk drive?
</para></question><answer>
<para>(By the "geometry" of a disk, we mean the number of cylinders,
heads and sectors/track on a disk - I'll 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>
<para>This seems to cause a lot of confusion for some reason. First
of all, the <emphasis remap=tt>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 "the" physical geometry, as the sector density
varies across the disk - what manufacturers claim is the "true"
physical geometry is usually the geometry that they've worked out
results in the least wasted space. For IDE disks, FreeBSD does
work in terms of C/H/S, but all modern drives will convert this
into block references internally as well.</para>
<para>All that matters is the <emphasis remap=tt>logical</emphasis> geometry - the answer that the
BIOS gets when it asks "what is your geometry?" and then uses to access
the disk. As FreeBSD uses the BIOS when booting, it's 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 "support for DOS disks &gt;1GB" or something
similar). If it's turned off, then use N cylinders, 64 heads
and 32 sectors/track, where 'N' 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 remap=tt>is</emphasis> turned on (it's often supplied this way to get around
certain limitations in MSDOS) and the disk capacity is more than 1GB,
use M cylinders, 63 sectors per track (*not* 64), and 255 heads, where
'M' 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
correct geometry should then be detected (and you can always remove
the DOS partition in the partition editor if you don't want to keep
it, or leave it around for programming network cards and the like).</para>
<para>Alternatively, there is a freely available utility distributed with
FreeBSD called ``<filename>pfdisk.exe</filename>'' (located in the <emphasis remap=tt>tools</emphasis>
subdirectory on the FreeBSD CDROM or on the various FreeBSD
ftp sites) which 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>
<para>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>
<para> What about disk managers? Or, I have a large drive!
</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 don't 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're 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 the FreeBSD boot partition and the slice for the other
operating system are in the first 1024 cylinders. If you're
reasonably careful, a 20 megabyte boot partition should be plenty.</para>
</answer></qandaentry>
<qandaentry><question
id="missing-os">
<para> When I boot FreeBSD I get ``Missing Operating System''
</para></question><answer>
<para>This is classically a case of FreeBSD and DOS or some other OS
conflicting over their ideas of disk <xref linkend="geometry" remap="geometry."> You will have to reinstall FreeBSD, but obeying the
instructions given above will almost always get you going.</para>
</answer></qandaentry>
<qandaentry><question>
<para>I can't get past the boot manager's `F?' 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 ``&gt;1GB drive support''), try
toggling its setting and reinstalling FreeBSD.</para>
</answer></qandaentry>
<qandaentry><question
id="bigram">
<para> I have &gt;16MB of RAM. Will this cause any problems?
</para></question><answer>
<para>Apart from performance issues, no. FreeBSD 2.X comes with bounce
buffers which allow your bus mastering controller access to greater
than 16MB. (Note that this should only be required if you are using
ISA devices, although one or two broken EISA and VLB devices may
need it as well).</para>
<para>Also look at the section on <xref linkend="reallybigram" remap="&gt;64M machines"> if you have that much memory,
or if you're using a Compaq or other BIOS that lies about
the available memory.</para>
</answer></qandaentry>
<qandaentry><question>
<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 ``<emphasis remap=tt>base</emphasis>'' source kit, which
includes several of the files mentioned here, and the
``<emphasis remap=tt>sys</emphasis>'' (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
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?config">config</ulink>. 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. (Because of 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. The <filename>src/install.sh</filename> script
will also install partial pieces of the source distribution,
depending on the arguments you pass it.</para>
</answer></qandaentry>
<qandaentry><question>
<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 a much friendlier kernel
configuration tool. When at the FreeBSD boot prompt (boot:),
use the "-c" 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.</para>
<para>It's still recommended that you eventually build a new
kernel containing just the drivers that you need, just to save a
bit of RAM, but it's no longer a strict requirement for most
systems.</para>
</answer></qandaentry>
<qandaentry><question>
<para>I live outside the US. Can I use DES encryption?</para></question><answer>
<para>If it is not absolutely imperative that you use DES style
encryption, you can use FreeBSD's default encryption for even
<emphasis remap=bf>better</emphasis> security, and with no export restrictions. FreeBSD
2.0's password default scrambler is now <emphasis remap=bf>MD5</emphasis>-based, and is
more CPU-intensive to crack with an automated password cracker
than DES, and allows longer passwords as well. The only reason
for not using the <emphasis remap=bf>MD5</emphasis>-based crypt today would be to use the
the same password entries on FreeBSD and non-FreeBSD systems.</para>
<para>Since the DES encryption algorithm cannot legally be exported
from the US, non-US users should not download this software (as
part of the <emphasis remap=tt>secrdist</emphasis> from US FTP sites.</para>
<para>There is however a replacement libcrypt available, based on
sources written in Australia by David Burren. This code is now
available on some non-US FreeBSD mirror sites. Sources for the
unencumbered libcrypt, and binaries of the programs which use it,
can be obtained from the following FTP sites:</para>
<para>
<variablelist>
<varlistentry><term>South Africa</term>
<listitem>
<para><filename>ftp://ftp.internat.FreeBSD.org/pub/FreeBSD</filename><!-- <br> -->
<filename>ftp://storm.sea.uct.ac.za/pub/FreeBSD</filename></para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>Brazil</term>
<listitem>
<para><filename>ftp://ftp.iqm.unicamp.br/pub/FreeBSD</filename></para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>Finland</term>
<listitem>
<para><filename>ftp://nic.funet.fi/pub/unix/FreeBSD/eurocrypt</filename></para>
</listitem>
</varlistentry>
</variablelist>
</para>
<para>The non-US <emphasis remap=tt>securedist</emphasis> can be used as a direct replacement
for the encumbered US <emphasis remap=tt>securedist</emphasis>. This <emphasis remap=tt>securedist</emphasis>
package is installed the same way as the US package (see
installation notes for details). If you are going to install DES
encryption, you should do so as soon as possible, before
installing other software.</para>
<para>Non-US users should please not download any encryption software
from the USA. This can get the maintainers of the sites from
which the software is downloaded into severe legal difficulties.</para>
<para>A non-US distribution of Kerberos is also being developed, and
current versions can generally be obtained by anonymous FTP from
<filename>braae.ru.ac.za</filename>.</para>
<para>There is also a <xref linkend="mailing" remap="mailing list"> for the
discussion of non-US encryption software. For more information, send
an email message with a single line saying ``<emphasis remap=tt>help</emphasis>'' in the body
of your message to</para>
<para><email>&lt;majordomo@braae.ru.ac.za&gt;</email>.</para>
</answer></qandaentry>
<qandaentry><question>
<para>The boot floppy starts but hangs at the ``Probing Devices...''
screen.</para></question><answer>
<para>If you have a IDE Zip 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>
<para>I get a ``panic: cant mount root'' 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>
<para>
<orderedlist>
<listitem>
<para>At the Boot: prompt, enter
<emphasis remap=tt>1:wd(2,a)kernel</emphasis> and press Enter. If the system starts, then
run the command
<literallayout>echo "1:wd(2,a)kernel" &gt; /boot.config</literallayout>
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="../handbook/kernelconfig.html">Rebuild your kernel,</ulink>
modify the wd configuration lines to read:
<literallayout>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</literallayout>
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>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>What are the limits for memory?</para></question><answer>
<para>For memory, the (theoretical) limit is 4 gigabytes. One gigabyte
has been tested; you generally can't buy i386 PCs that can support
much more than that.</para>
</answer></qandaentry>
<qandaentry><question>
<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
(4TB) if the block size is 4K.</para>
<para>
<literallayout> maxfilesize
----------------------------------
2.2.7 3.0
fs block size -stable -current works should-work
------------- ------- -------- ----- -----------
4K 4T-1 4T-1 4T-1 4+T
8K 32+G 8T-1 32+G 16T-1
16K 128+G 16T-1 128+G 32T-1
32K 512+G 32T-1 512+G 64T-1
64K 2048+G 64T-1 2048+G 128T-1
</literallayout>
</para>
<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 maxiumum 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>
<para>How can I put 1TB files on my floppy?</para></question><answer>
<para>I keep several virtual ones on floppies :-). The maxiumum
file size is not closely related to the maximum disk size. The
maximum disk size is 1TB. It is a feature that the file size can be
larger than the disk size.</para>
<para>The following example creates a file of size 8T-1 using a
whole 32K of disk space (3 indirect blocks and 1 data block) on a
small root partition. The dd command requires a dd that works with
large files.</para>
<para>
<literallayout>ttyv0:bde@alphplex:/tmp/q&gt; cat foo
df .
dd if=/dev/zero of=z bs=1 seek=`echo 2^43 - 2 | bc` count=1
ls -l z
du z
df .
ttyv0:bde@alphplex:/tmp/q&gt; sh foo
Filesystem 1024-blocks Used Avail Capacity Mounted on
/dev/sd0a 64479 27702 31619 47% /
1+0 records in
1+0 records out
1 bytes transferred in 0.000187 secs (5346 bytes/sec)
-rw-r--r-- 1 bde bin 8796093022207 Sep 7 16:04 z
32 z
Filesystem 1024-blocks Used Avail Capacity Mounted on
/dev/sd0a 64479 27734 31587 47% /
ttyv0:bde@alphplex:/tmp/q&gt; exit</literallayout>
</para>
<para>Bruce Evans, September 1998</para>
</answer></qandaentry>
<qandaentry><question>
<para>I compiled a new kernel and now I get the error message "archsw.readin.failed" when booting.</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></qandaset>
</chapter>
<chapter
id="hardware">
<title>Hardware compatibility </title>
<qandaset><qandaentry><question>
<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 "Western Digital" 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>
<para>Which SCSI controllers are supported?</para></question><answer>
<para>See the complete list in the
<ulink URL="../handbook/install.html#INSTALL-HW">Handbook</ulink>.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Which CD-ROM drives are supported by FreeBSD?</para></question><answer>
<para>Any SCSI drive connected to a supported controller is supported.</para>
<para>The following proprietary CD-ROM interfaces are also supported:</para>
<para>
<itemizedlist>
<listitem>
<para>Mitsumi LU002 (8bit), LU005 (16bit) and FX001D (16bit 2x Speed).</para>
</listitem>
<listitem>
<para>Sony CDU 31/33A<!-- <br> --></para>
</listitem>
<listitem>
<para>Sound Blaster Non-SCSI CD-ROM<!-- <br> --></para>
</listitem>
<listitem>
<para>Matsushita/Panasonic CD-ROM<!-- <br> --></para>
</listitem>
<listitem>
<para>ATAPI compatible IDE CD-ROMs<!-- <br> --></para>
</listitem>
</itemizedlist>
</para>
<para>All non-SCSI cards are known to be extremely slow compared to
SCSI drives, and some ATAPI CDROMs may not work.</para>
<para>As of 2.2 the FreeBSD CDROM from Walnut Creek supports booting
directly from the CD.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Does FreeBSD support ZIP drives?</para></question><answer>
<para>FreeBSD supports the SCSI ZIP drive out of the box, of course. The
ZIP drive 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. I don't know which host adapters let you boot from targets
other than 0 or 1... look at your docs (and let me know if it works
out for you).</para>
<para>ATAPI (IDE) Zip drives are supported in FreeBSD 2.2.6 and
later releases.</para>
<para>FreeBSD has contained support for Parallel Port Zip Drives since
version 3.0. If you are using a sufficiently up to date version, then
you should check that your kernel contains the <emphasis remap=tt>scbus0</emphasis>, <emphasis remap=tt>da0</emphasis>, <emphasis remap=tt>ppbus0</emphasis>, and <emphasis remap=tt>vp0</emphasis> drivers (the GENERIC kernel
contains everything except vp0). With all these drivers present, the
Parallel Port drive should be available as /dev/da0s4. Disks can
be mounted using <command>mount /dev/da0s4 /mnt</command> OR (for dos disks) <emphasis remap=tt>mount_msdos /dev/da0s4 /mnt</emphasis> as appropriate.</para>
<para>Also check out <link linkend="jaz">this note on removable drives</link>,
and <link linkend="disklabel">this note on 'formatting'</link>.</para>
</answer></qandaentry>
<qandaentry><question>
<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 the should all look like SCSI disks to FreeBSD, and
the IDE EZ should look like an IDE drive.</para>
<para><anchor id="jaz">I'm 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 'formatting'</link>.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Which multi-port serial cards are supported by FreeBSD?</para></question><answer>
<para>There is a list of these in the <ulink URL="../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 <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?sio">sio</ulink> man page to get more information on configuring such cards.</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
manufactures as Microsoft, Logitech and ATI. The bus device driver
is compiled in the GENERIC kernel by default. If you are building
a custom kernel with the bus mouse driver, make sure to add the
following line to the kernel config file:</para>
<para>
<literallayout> device mse0 at isa? port 0x23c tty irq5 vector mseintr
</literallayout>
</para>
<para>The bus mouse usually comes with an dedicatd interface card.
It 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
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?mse">mse</ulink>
man page for more information.</para>
</answer></qandaentry>
<qandaentry><question
id="ps2mouse">
<para> How do I use my PS/2 (``mouse port'' or ``keyboard'') mouse?</para></question><answer>
<para>If you're running a post-2.2.5 version of FreeBSD, the necessary
driver, psm, is included and enabled in the kernel. The kernel
should detect your PS/2 mouse at boot time.</para>
<para>If you're running a previous but relatively recent version of
FreeBSD (2.1.x or better) then you can simply enable it in the
kernel configuration menu at installation time, otherwise later with
-c at the boot: prompt. It is disabled by default, so you will need
to enable it explicitly.</para>
<para>If you're running an older version of FreeBSD then you'll have to
add the following lines to your kernel configuration file and compile
a new kernel:</para>
<para>
<literallayout> device psm0 at isa? port "IO_KBD" conflicts tty irq 12 vector psmintr
</literallayout>
</para>
<para>See the <ulink URL="../handbook/kernelconfig.html">Handbook entry on configuring the kernel</ulink> if you've no
experience with building kernels.</para>
<para>Once you have a kernel detecting psm0 correctly at boot time,
make sure that an entry for psm0 exists in /dev. You can do this
by typing:</para>
<para>
<literallayout> cd /dev; sh MAKEDEV psm0
</literallayout>
</para>
<para>when logged in as root.</para>
</answer></qandaentry>
<qandaentry><question
id="moused">
<para>Is it possible to make use of a mouse in any way outside the X Window?</para></question><answer>
<para>If you are using the default console driver, syscons, you can
use a mouse pointer in text consoles to cut &amp; paste text.
Run the mouse daemon, moused, and turn on the mouse pointer
in the virtual console:</para>
<para>
<literallayout> moused -p /dev/xxxx -t yyyy
vidcontrol -m on
</literallayout>
</para>
<para>Where <emphasis remap=tt>xxxx</emphasis> is the mouse device name and <emphasis remap=tt>yyyy</emphasis>
is a protocol type for the mouse. See the
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?moused">moused</ulink>
man page for supported protocol types. </para>
<para>You may wish to run the mouse daemon automatically when the
system starts. In version 2.2.1, set the following variables in
<filename>/etc/sysconfig</filename>.</para>
<para>
<literallayout> mousedtype="yyyy"
mousedport="xxxx"
mousedflags=""
</literallayout>
</para>
<para>In versions 2.2.2 or later, set the following variables in
<filename>/etc/rc.conf</filename>.</para>
<para>
<literallayout> moused_type="yyyy"
moused_port="xxxx"
moused_flags=""
</literallayout>
</para>
<para>Staring from FreeBSD 2.2.6, the mouse daemon is capable of
determining the correct protocol type automatically unless the mouse
is a relatively old serial mouse model. Specify ``<emphasis remap=tt>auto</emphasis>'' as
the protocol to invoke automatic detection.</para>
<para>When the mouse daemon is running, access to the mouse needs to be
coordinated between the mouse daemon and other programs such as the
X Window. Refer to <xref linkend="x-and-moused" remap="another section">
on this issue".</para>
</answer></qandaentry>
<qandaentry><question>
<para>How do I cut and paste text with mouse in the text console?</para></question><answer>
<para>Once you get the mouse daemon running (see <xref linkend="moused" remap="previous section">), hold down the button 1 (left button)
and move the mouse to select a region of
text. Then, press the button 2 (middle button) or the button 3 (right
button) to paste it at the text cursor.</para>
<para>In versions 2.2.6 and later, pressing the button 2 will paste
the text. Pressing the button 3 will ``extend'' the selected region
of text. If your mouse does not have the middle button, you may wish
to emulate it or remap buttons using moused options. See the
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?moused">moused</ulink>
man page for details.</para>
</answer></qandaentry>
<qandaentry><question>
<para>My mouse has a fancy wheel and buttons. Can I use them in FreeBSD?</para></question><answer>
<para>The answer is, unfortunately, ``It depends.'' 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>
</answer></qandaentry>
<qandaentry><question>
<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>. And check out <link linkend="pao">this note</link> on the Mobile
Computing page.</para>
</answer></qandaentry>
<qandaentry><question>
<para>What types of tape drives are supported?</para></question><answer>
<para>FreeBSD supports SCSI, QIC-36 (with a QIC-02 interface) and
QIC-40/80 (Floppy based) tape drives. This includes 8-mm (aka Exabyte)
and DAT drives. The QIC-40/80 drives are known to be slow.</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>
<para>Does FreeBSD support tape changers?</para></question><answer>
<para>FreeBSD 2.2 supports SCSI changers using the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ch(4)">ch</ulink> device and
the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?chio">chio</ulink>
command. The details of how you actually control the changer can be
found in the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?chio">chio</ulink> man page.</para>
<para>If you're not using <ulink URL="http://www.FreeBSD.org/cgi/ports.cgi?amanda">AMANDA</ulink> or
some other product that already understands changers, remember that
they're 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>
<para>Which sound cards are supported by FreeBSD?</para></question><answer>
<para>FreeBSD supports the SoundBlaster, SoundBlaster Pro, SoundBlaster
16, Pro Audio Spectrum 16, AdLib and Gravis UltraSound sound cards.
There is also limited support for MPU-401 and compatible MIDI cards.
Cards conforming to the Microsoft Sound System specification are also
supported through the pcm driver.</para>
<para><acronym>NOTE</acronym> This is only for sound! This driver does not support
CD-ROMs, SCSI or joysticks on these cards, except for the
SoundBlaster. The SoundBlaster SCSI interface and some non-SCSI
CDROMS are supported, but you can't boot off this device.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Workarounds for no sound from es1370 with pcm driver?</para></question><answer>
<para>You can run the following command everytime the machine booted up:</para>
<para>mixer pcm 100 vol 100 cd 100</para>
</answer></qandaentry>
<qandaentry><question>
<para>Which network cards does FreeBSD support?</para></question><answer>
<para>See the <ulink URL="../handbook/install.html#INSTALL-NICS">Ethernet cards</ulink> section of the handbook for a more
complete list. </para>
</answer></qandaentry>
<qandaentry><question>
<para>I don't have a math co-processor - is that bad?</para></question><answer>
<para><emphasis remap=tt>Note</emphasis> This will only affect 386/486SX/486SLC owners - other
machines will have one built into the CPU.</para>
<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 <xref linkend="emul" remap="on FP emulation">). In particular, drawing arcs in X will be
VERY slow. It is highly recommended that you buy a math
co-processor; it's well worth it.</para>
<para><acronym>NOTE</acronym> Some math co-processors are better than others. It pains
us to say it, but nobody ever got fired for buying Intel. Unless
you're sure it works with FreeBSD, beware of clones.</para>
</answer></qandaentry>
<qandaentry><question>
<para>What other devices does 2.X support?</para></question><answer>
<para>See the <ulink URL="../handbook/install.html#INSTALL-MISC">Handbook</ulink>
for the list of other devices supported.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Does FreeBSD support power management on my laptop?</para></question><answer>
<para>FreeBSD supports APM on certain machines. Please look in the
<acronym>LINT</acronym> kernel config file, searching for the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?apm">APM</ulink> keyword.</para>
</answer></qandaentry>
<qandaentry><question>
<para>My Micron system hangs 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 don't get configured at their reported addresses.</para>
<para>Disable the "Plug and Play Operating System" 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>
<para>I have a newer Adaptec controller and FreeBSD can't find it.
</para></question><answer>
<para>The newer AIC789x series Adaptec chips are supported under the CAM SCSI
framework which made it's debut in 3.0. Patches against 2.2-STABLE
are in <ulink URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/development/cam/">ftp://ftp.FreeBSD.org/pub/FreeBSD/development/cam/</ulink>.
A CAM-enhanced boot floppy is available at <ulink URL="http://www.FreeBSD.org/~abial/cam-boot/">http://www.FreeBSD.org/~abial/cam-boot/</ulink>. In both cases read the README before
beginning. </para>
</answer></qandaentry>
<qandaentry><question>
<para>I have an internal Plug &amp; Play modem and FreeBSD can't find it.
</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 <emphasis remap=tt>controller pnp0</emphasis> 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 "SUP1310"
in the structure "siopnp_ids[]" 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 `pnp' command in the
boot-time configuration with a command like
<literallayout> pnp 1 0 enable os irq0 3 drq0 0 port0 0x2f8
</literallayout>
to make the modem show.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How do I get the boot: prompt to show on the serial console?
</para></question><answer>
<para>
<orderedlist>
<listitem>
<para>Build a kernel with <emphasis remap=tt>options COMCONSOLE</emphasis>.</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>
<para>See <filename>/usr/src/sys/i386/boot/biosboot/README.serial</filename> for information.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Why doesn't my 3Com PCI network card 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 "Plug and Play Operating
System" 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">http://cesdis.gsfc.nasa.gov/linux/drivers/vortex.html#micron</ulink></para>
</answer></qandaentry>
<qandaentry><question>
<para>Does FreeBSD support Symmetric Multiproccessing (SMP)?
</para></question><answer>
<para>SMP is supported in 3.0-STABLE and later releases only.</para>
</answer></qandaentry></qandaset>
</chapter>
<chapter
id="troubleshoot">
<title>Troubleshooting</title>
<qandaset><qandaentry><question
id="awre">
<para>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'll need to edit the first device page mode,
which can be done on FreeBSD by giving the command (as root)</para>
<para>
<literallayout> scsi -f /dev/rsd0c -m 1 -e -P 3
</literallayout>
</para>
<para>and changing the values of AWRE and ARRE from 0 to 1:-</para>
<para>
<literallayout> AWRE (Auto Write Reallocation Enbld): 1
ARRE (Auto Read Reallocation Enbld): 1
</literallayout>
</para>
<para>The following paragraphs were submitted by
<ulink URL="mailto:tedm@toybox.placo.com">Ted Mittelstaedt</ulink>:</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
BIOS, therefore a mechanism, bad144, exists that replaces this
functionality. bad144 only works with the wd driver,
it is NOT 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 "Bad Block" 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 "translated" geometry with the "set geometry" command
in fdisk. You must also NOT use the "dangerously dedicated" 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 "cooperative" 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 Alt-F2)
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>
<para>FreeBSD does not recognize my Bustek 742a EISA SCSI!</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 ``versions'' 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 doesn't 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 ``round robin''</para>
<para>The Buslogic cards also have a serial number on them. If you
have a 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 ``emulation'' 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>
<para>The 742a EISA cards never had the ``&gt;16MB'' problem mentioned in
the section <xref linkend="bigram" remap="on &gt;16 MB machines">. This is a
problem that occurs with the Vesa-Local Buslogic SCSI cards.</para>
</answer></qandaentry>
<qandaentry><question>
<para> My HP Netserver's SCSI controller is not detected!
</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 ``true'' 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 <symbol>EISA_SLOTS</symbol>
to a value of 12.
Configure and compile a kernel, as described in the
<ulink URL="../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 ``visual'' interface, but the plain command-line
interface there. Simply type</para>
<para>
<literallayout> eisa 12
quit
</literallayout>
</para>
<para>at the prompt, and install your system as usual. While it's
recommended you compile and install a custom kernel anyway,</para>
<para><ulink URL="http://www.FreeBSD.org/cgi/man.cgi?dset">dset</ulink>
now also understands to save this value.</para>
<para>Hopefully, future versions will have a proper fix for this problem.</para>
<para><emphasis remap=tt>NOTE:</emphasis> You can not use a <emphasis remap=bf>dangerously dedicated</emphasis> disk with
an HP Netserver. See <link linkend="dedicate">this note</link> for
more info.</para>
</answer></qandaentry>
<qandaentry><question>
<para>What's up with this CMD640 IDE controller?</para></question><answer>
<para>It's broken. It cannot handle commands on both channels
simultaneously.</para>
<para>There's a workaround available now and it is enabled automatically
if your system uses this chip. For the details refer to the
manual page of the disk driver (man 4 wd).</para>
<para>If you're already running FreeBSD 2.2.1 or 2.2.2 with a
CMD640 IDE controller and you want to use the second channel,
build a new kernel with <emphasis remap=tt>options "CMD640"</emphasis> enabled. This
is the default for 2.2.5 and later.</para>
</answer></qandaentry>
<qandaentry><question>
<para>I keep seeing messages like ``<emphasis remap=tt>ed1: timeout</emphasis>''.</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're 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>
<para>When I mount a CDROM, I get ``Incorrect super block''.</para></question><answer>
<para>You have to tell
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?mount">mount</ulink>
the type of the device that you want to mount. By default,
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?mount">mount</ulink>
will assume the filesystem is of type ``<emphasis remap=tt>ufs</emphasis>''. You want to mount
a CDROM filesystem, and you do this by specifying the ``<option>-t cd9660</option>''
option to <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?mount">mount</ulink>. This does, of course, assume that the
CDROM contains an ISO 9660 filesystem, which is what most CDROMs
have. As of 1.1R, FreeBSD automatically understands the Rock Ridge
(long filename) extensions as well.</para>
<para>As an example, if you want to mount the CDROM device,
``<filename>/dev/cd0c</filename>'', under <filename>/mnt</filename>, you would execute:</para>
<para>
<literallayout> mount -t cd9660 /dev/cd0c /mnt
</literallayout>
</para>
<para>Note that your device name (``<filename>/dev/cd0c</filename>'' in this
example) could be different, depending on the CDROM interface.
Note that the ``<option>-t cd9660</option>'' option just causes the
``<symbol>mount_cd9660</symbol>'' command to be executed, and so the
above example could be shortened to:</para>
<para>
<literallayout> mount_cd9660 /dev/cd0c /mnt
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>When I mount a CDROM, I get ``Device not configured''.</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. Feed the drive
something, and/or check its master/slave status if it is
IDE (ATAPI). It can take a couple of seconds for a CDROM drive
to notice that it's been fed, so be patient.</para>
<para>Sometimes a SCSI CD-ROM may be missed because it hadn't enough time
to answer the bus reset. If you have a SCSI CD-ROM please try to
add the following symbol into your kernel configuration file
and recompile.</para>
<para>
<literallayout> options "SCSI_DELAY=15"
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>My printer is ridiculously slow. What can I do ?</para></question><answer>
<para>If it's parallel, and the only problem is that it's terribly
slow, try setting your printer port into ``polled'' mode:</para>
<para>
<literallayout> lptcontrol -p
</literallayout>
</para>
<para>Some newer HP printers are claimed not to work correctly in
interrupt mode, apparently due to some (not yet exactly
understood) timing problem.</para>
</answer></qandaentry>
<qandaentry><question>
<para>My programs occasionally die with ``Signal 11'' errors.</para></question><answer>
<para>This can be caused by bad hardware (memory, motherboard, etc.).
Try running a memory-testing program on your PC. Note that, even
though every memory testing program you try will report your
memory as being fine, it's possible for slightly marginal memory
to pass all memory tests, yet fail under operating conditions
(such as during bus mastering DMA from a SCSI controller like the
Adaptec 1542, when you're beating on memory by compiling a kernel,
or just when the system's running particularly hot).</para>
<para>The SIG11 FAQ (listed below) points up slow memory as being the
most common problem. Increase the number of wait states in your
BIOS setup, or get faster memory.</para>
<para>For me the guilty party has been bad cache RAM or a bad on-board
cache controller. Try disabling the on-board (secondary) cache in
the BIOS setup and see if that solves the problem.</para>
<para>There's an extensive FAQ on this at
<ulink URL="http://www.bitwizard.nl/sig11/">the SIG11 problem FAQ</ulink></para>
</answer></qandaentry>
<qandaentry><question>
<para>When I boot, the screen goes black and loses sync!</para></question><answer>
<para>This is a known problem with the ATI Mach 64 video card.
The problem is that this card uses address <emphasis remap=tt>2e8</emphasis>, and
the fourth serial port does too. Due to a bug (feature?) in the
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?sio">sio.c</ulink>
driver it will touch this port even if you don't have the
fourth serial port, and <emphasis remap=bf>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>
<para>
<orderedlist>
<listitem>
<para>Enter <option>-c</option> at the bootprompt. (This will put the kernel
into configuration mode).
</para>
</listitem>
<listitem>
<para>Disable <emphasis remap=tt>sio0</emphasis>, <emphasis remap=tt>sio1</emphasis>, <emphasis remap=tt>sio2</emphasis> and <emphasis remap=tt>sio3</emphasis>
(all of them). This way the sio driver doesn't get activated
-&gt; no problems.
</para>
</listitem>
<listitem>
<para>Type exit to continue booting.</para>
</listitem>
</orderedlist>
</para>
<para>If you want to be able to use your serial ports,
you'll 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
X Window does not work properly. Some newer ATI Mach 64 video
cards (notably ATI Mach Xpression) do not run with the current
version of <emphasis remap=tt>XFree86</emphasis>; the screen goes black when you start
X Window, or it works with strange problems. You can get
a beta-version of a new X-server that works better, by looking at
<ulink URL="http://www.xfree86.org/">the XFree86 site</ulink>
and following the links to the new beta release. Get the
following files:</para>
<para><emphasis remap=tt>AccelCards, BetaReport, Cards, Devices, FILES, README.ati,
README.FreeBSD, README.Mach64, RELNOTES, VGADriver.Doc,
X312BMa64.tgz</emphasis></para>
<para>Replace the older files with the new versions and make sure you
run <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?manpath=xfree86&amp;query=xf86config">xf86config</ulink> again.</para>
</answer></qandaentry>
<qandaentry><question
id="reallybigram">
<para> I have 128 MB of RAM but the system only uses 64 MB.
</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 don't have room in the
bootblocks to do it. Someday when lack of room in the bootblocks
is fixed, we'll use the extended BIOS functions to get the full
memory information...but for now we're stuck with the kernel
option.</para>
<para><literal>options "MAXMEM=&lt;n&gt;"</literal></para>
<para>Where <emphasis remap=tt>n</emphasis> is your memory in Kilobytes. For a 128 MB machine,
you'd want to use <emphasis remap=tt>131072</emphasis>.</para>
</answer></qandaentry>
<qandaentry><question>
<para>FreeBSD 2.0 panics with ``kmem_map too small!''</para></question><answer>
<para><emphasis remap=tt>Note</emphasis> The message may also be ``mb_map too small!''</para>
<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=&lt;n&gt;"</literal></para>
<para>to your kernel config file, where &lt;n&gt; is a number in the
range 512-4096, depending on the number of concurrent TCP
connections you need to support. I'd 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
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?netstat">netstat -m</ulink>. The default value for NMBCLUSTERS is
<emphasis remap=tt>512 + MAXUSERS * 16</emphasis>.</para>
</answer></qandaentry>
<qandaentry><question>
<para>``CMAP busy panic'' 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>
<para>
<literallayout> rm /var/db/kvm_*.db
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>ahc0: brkadrint, Illegal Host Access at seqaddr 0x0</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 <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?uha(4)">uha0</ulink>, which is causing the problem.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Sendmail says ``mail loops back to myself''</para></question><answer>
<para>This is answered in the sendmail FAQ as follows:-</para>
<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 doesn't recognize
itself as domain.net. Add domain.net to /etc/sendmail.cw
(if you are using FEATURE(use_cw_file)) or add "Cw domain.net"
to /etc/sendmail.cf.
</literallayout>
</para>
<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
<ulink URL="mailto:mail-server@rtfm.mit.edu">mail-server@rtfm.mit.edu</ulink> with the command "send
usenet/news.answers/mail/sendmail-faq" as the body of the
message.</para>
</answer></qandaentry>
<qandaentry><question>
<para>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 <emphasis remap=tt>cons25</emphasis> terminal type
required by the FreeBSD console.</para>
<para>There are a number of possible work-arounds for this problem:
<itemizedlist>
<listitem>
<para>After logging on to the remote machine, set your TERM shell
variable to <emphasis remap=tt>ansi</emphasis> or
<emphasis remap=tt>sco</emphasis> if the remote machine knows
about these terminal types.</para>
</listitem>
<listitem>
<para>Use a VT100 emulator like <ulink URL="http://www.FreeBSD.org/cgi/ports.cgi?screen-">screen</ulink>
at the FreeBSD console.
<emphasis remap=tt>screen</emphasis> offers you the ability to run multiple
concurrent sessions from one terminal, and is a neat program in its own right.
Each <emphasis remap=tt>screen</emphasis> window behaves like a VT100 terminal,
so the TERM variable at the remote end should be set to <emphasis remap=tt>
vt100</emphasis>.
</para>
</listitem>
<listitem>
<para>Install the <emphasis remap=tt>cons25</emphasis> 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 <emphasis remap=tt>xterm</emphasis> or
<emphasis remap=tt>rxvt</emphasis>. The TERM variable at the remote host
should be set to <emphasis remap=tt>xterm</emphasis> or <emphasis remap=tt>vt100
</emphasis>.</para>
</listitem>
</itemizedlist>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>My machine prints "calcru: negative time..."</para></question><answer>
<para>This can be caused by various hardware and/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 "SIGXCPU exceeded cpu time limit".</para>
<para>For FreeBSD 3.0 and later from Nov 29, 1998 forward: If the
problem cannot be fixed otherwise the solution is to set
this sysctl variable:
<literallayout> sysctl -w kern.timecounter.method=1</literallayout>
</para>
<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 "NTIMECOUNTER"
option in your kernel to increasingly large values. If by the
time you have reached "NTIMECOUNTER=20" the problem isn't
solved, interrupts are too hosed on your machine for reliable
timekeeping.</para>
</answer></qandaentry></qandaset>
</chapter>
<chapter
id="commercial">
<title>Commercial Applications</title>
<para><acronym>NOTE</acronym> This section is still very sparse, though we're 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="../commercial/commercial.html">the Vendors page</ulink>
for a longer list.</para>
<qandaset><qandaentry><question>
<para>Where can I get Motif for FreeBSD?</para></question><answer>
<para>Contact <link linkend="apps2go">Apps2go</link> for an ELF Motif 2.1
distribution for FreeBSD.<anchor id="apps2go"></para>
<para>This distribution includes:
<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 (for use with FreeBSD 3.0
and above).
</para>
</listitem>
<listitem>
<para>Demonstration applets.</para>
</listitem>
</itemizedlist>
</para>
<para>Be sure to specify that you want the FreeBSD version of Motif
when ordering! Versions for NetBSD and OpenBSD are also sold by
<emphasis>Apps2go</emphasis>. This is currently a FTP only download.</para>
<para>
<variablelist>
<varlistentry><term>More info</term>
<listitem>
<para><ulink URL="http://www.apps2go.com/">Apps2go WWW page</ulink></para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>or</term>
<listitem>
<para><ulink URL="mailto:sales@apps2go.com">Sales</ulink> or
<ulink URL="mailto:support@apps2go.com">Support</ulink> email addresses.</para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>or</term>
<listitem>
<para>phone (817) 431 8775 or +1 817 431-8775</para>
</listitem>
</varlistentry>
</variablelist>
</para>
<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:
<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 eariler).
</para>
</listitem>
<listitem>
<para>Demonstration applets.
</para>
</listitem>
<listitem>
<para>Preformatted man pages.</para>
</listitem>
</itemizedlist>
</para>
<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:
<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
eariler).
</para>
</listitem>
<listitem>
<para>Demonstration applets.
</para>
</listitem>
<listitem>
<para>Preformatted man pages.</para>
</listitem>
</itemizedlist>
</para>
<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>
<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.</para>
</answer></qandaentry>
<qandaentry><question>
<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> sells
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 convienent 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>
<para>
<variablelist>
<varlistentry><term>More info</term>
<listitem>
<para><ulink URL="http://www.metrolink.com/">Metro Link WWW page</ulink></para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>or</term>
<listitem>
<para><ulink URL="mailto:sales@metrolink.com">Sales</ulink> or
<ulink URL="mailto:tech@metrolink.com">Support</ulink> email addresses.</para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>or</term>
<listitem>
<para>phone (954) 938-0283 or +1 954 938-0283</para>
</listitem>
</varlistentry>
</variablelist>
</para>
<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 taylored for
laptop support.<anchor id="xig"></para>
<para>There is a free "compatibility demo" of version 5.0 available.</para>
<para>Xi Graphics also sells Motif and CDE for FreeBSD (see above).</para>
<para>
<variablelist>
<varlistentry><term>More info</term>
<listitem>
<para><ulink URL="http://www.xig.com/">Xi Graphics WWW page</ulink></para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>or</term>
<listitem>
<para><ulink URL="mailto:sales@xig.com">Sales</ulink> or
<ulink URL="mailto:support@xig.com">Support</ulink> email addresses.</para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>or</term>
<listitem>
<para>phone (800) 946 7433 or +1 303 298-7478.</para>
</listitem>
</varlistentry>
</variablelist>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>Are there any Database systems for FreeBSD?</para></question><answer>
<para>Yes! See the <ulink URL="../commercial/software_bycat.html#CATEGORY_DATABASE">Commercial Vendors</ulink> section of FreeBSD's Web site.</para>
<para>Also see the <ulink URL="../ports/databases.html">Databases</ulink> section of the Ports collection.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Can I run Oracle on FreeBSD?</para></question><answer>
<para>Yes. The following pages tell you exactly how to setup Linux-Oracle
on FreeBSD:</para>
<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>
</para>
</answer></qandaentry></qandaset>
</chapter>
<chapter
id="applications">
<title>User Applications</title>
<qandaset><qandaentry><question>
<para>So, where are all the user applications?</para></question><answer>
<para>Please take a look at <ulink URL="../ports/">the ports page</ulink> for info on software packages ported to
FreeBSD. The list currently tops 1800 and is growing daily, so come
back to check often or subscribe to the <emphasis remap=tt>freebsd-announce</emphasis>
<xref linkend="mailing" remap="mailing list"> for periodic updates on new
entries.</para>
<para>Most ports should be available for the 2.2, 3.x and 4.0
branches, and many of them should work on 2.1.x systems as
well. 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 ``package'', essentially no
more than a gzipped 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
<command>pkg_add(1)</command> command on the specific package files you're
interested in installing. Package files can usually be identified by
their <filename>.tgz</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>
<para>
<variablelist>
<varlistentry><term>for 2.2.8-release/2.2.8-stable</term>
<listitem>
<para><ulink URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-2.2.8/">ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-2.2.8/</ulink></para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>for 3.2-release/3.2-stable</term>
<listitem>
<para><ulink URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-3-stable/">ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-3-stable/</ulink></para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>for 4.0-current</term>
<listitem>
<para><ulink URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-current/">ftp://ftp.FreeBSD.org/pub/FreeBSD/ports/i386/packages-4-current/</ulink></para>
</listitem>
</varlistentry>
</variablelist>
</para>
<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>
<para>Where do I find libc.so.3.0?</para></question><answer>
<para>You are trying to run a package for 2.2/3.x/4.0 on a 2.1.x
system. Please take a look at the previous section and get
the correct port/package for your system.</para>
</answer></qandaentry>
<qandaentry><question
id="emul">
<para> ghostscript gives lots of errors with my 386/486SX.
</para></question><answer>
<para>You don't 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>
<para>
<literallayout> options GPL_MATH_EMULATE
</literallayout>
</para>
<para><acronym>NOTE</acronym> You will need to remove the <symbol>MATH_EMULATE</symbol>
option when you do this.</para>
</answer></qandaentry>
<qandaentry><question>
<para> When I run a SCO/iBCS2 application, it bombs on <emphasis remap=tt>socksys</emphasis>.
</para></question><answer>
<para>You first need to edit the <filename>/etc/sysconfig</filename>
(or <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?rc.conf(5)">/etc/rc.conf</ulink>) file in the last section to change the
following variable to <acronym>YES</acronym>:</para>
<para>
<literallayout> # Set to YES if you want ibcs2 (SCO) emulation loaded at startup
ibcs2=NO
</literallayout>
</para>
<para>It will load the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ibcs2">ibcs2</ulink>
kernel module at startup.</para>
<para>You'll then need to set up /compat/ibcs2/dev to look like:</para>
<para>
<literallayout>lrwxr-xr-x 1 root wheel 9 Oct 15 22:20 X0R@ -&gt; /dev/null
lrwxr-xr-x 1 root wheel 7 Oct 15 22:20 nfsd@ -&gt; socksys
-rw-rw-r-- 1 root wheel 0 Oct 28 12:02 null
lrwxr-xr-x 1 root wheel 9 Oct 15 22:20 socksys@ -&gt; /dev/null
crw-rw-rw- 1 root wheel 41, 1 Oct 15 22:14 spx
</literallayout>
</para>
<para>You just need socksys to go to <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?null(4)">/dev/null</ulink>
to fake the open &amp; close. The code in -current will handle the
rest. This is much cleaner than the way it was done before. If you
want the <emphasis remap=tt>spx</emphasis> driver for a local socket X connection, define
<symbol>SPX_HACK</symbol> when you compile the system.</para>
</answer></qandaentry>
<qandaentry><question>
<para> How do I configure INN (Internet News) for my machine?
</para></question><answer>
<para>After installing the inn package or port, an excellent place to
start is <ulink URL="http://www.cis.ohio-state.edu/~barr/INN.html">Dave Barr's INN Page</ulink> where you'll find the INN FAQ.</para>
</answer></qandaentry>
<qandaentry><question>
<para>What version of Microsoft FrontPage should I get?</para></question><answer>
<para>Use the Port, Luke! A pre-patched version of Apache is available
in the ports tree.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Does FreeBSD support Java?</para></question><answer>
<para>Yes. Please see <ulink URL="http://www.FreeBSD.org/java/">http://www.FreeBSD.org/java/</ulink>.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Why can't I build this port on my 3.x-stable machine?</para></question><answer>
<para>If you're running a FreeBSD version that lags significantly behind
-current or -stable, you may need a ports upgrade kit from
<ulink URL="http://www.FreeBSD.org/ports/">http://www.FreeBSD.org/ports/</ulink>. 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 <command>send-pr(1)</command> command, since the ports
collection is supposed to work for both the -current and -stable
branches.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Where do I find ld.so?</para></question><answer>
<para>If you want to run some aout applications like
Netscape Navigator on an Elf'ened machine such as 3.1-R or later,
it would need /usr/libexec/ld.so and some aout libs.
They are included in the compat22 distribution.
Use /stand/sysinstall or install.sh in the compat22 subdirectory
and install it.
Also read ERRATAs for 3.1-R and 3.2-R.</para>
</answer></qandaentry></qandaset>
</chapter>
<chapter
id="kernelconfig">
<title>Kernel Configuration</title>
<qandaset><qandaentry><question
id="make-kernel">
<para> I'd like to customize my kernel. Is it difficult?
</para></question><answer>
<para>Not at all! Check out the <ulink URL="../handbook/kernelconfig.html">kernel config section of the Handbook</ulink>.</para>
<para><emphasis remap=bf>NOTE:</emphasis> I recommend making a dated snapshot of your kernel
in <filename>kernel.YYMMDD</filename> after you get it all working, that way if
you do something dire the next time you play with your configuration
you can boot that kernel instead of having to go all the way back
to <filename>kernel.GENERIC</filename>. This is particularly important if you're
now booting off a controller that isn't supported in the GENERIC
kernel (yes, personal experience).</para>
</answer></qandaentry>
<qandaentry><question>
<para> My kernel compiles fail because <symbol>_hw_float</symbol> is missing.
</para></question><answer>
<para>Let me guess. You removed <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?npx(4)">npx0</ulink> from your
kernel configuration file because you don't have a math co-processor,
right? Wrong! :-) The <emphasis remap=tt>npx0</emphasis> is <acronym>MANDATORY</acronym>. Even if you don't
have a mathematic co-processor, you <emphasis remap=bf>must</emphasis> include the <emphasis remap=tt>npx0</emphasis>
device.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Interrupt conflicts with multi-port serial code.</para></question><answer>
<para><emphasis remap=bf>Q.</emphasis> 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><emphasis remap=bf>A.</emphasis> 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 a example:</para>
<para>
<literallayout> #
# 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
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>How do I enable support for QIC-40/80 drives?</para></question><answer>
<para>You need to uncomment the following line in the generic config
file (or add it to your config file), add a ``<literal>flags 0x1</literal>''
on the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?fdc(4)">fdc</ulink> line and recompile.</para>
<para>
<literallayout>controller fdc0 at isa? port "IO_FD1" bio irq 6 drq 2 flags 0x1 vector fdintr
disk fd0 at fdc0 drive 0 ^^^^^^^^^
disk fd1 at fdc0 drive 1
#tape ft0 at fdc0 drive 2
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
</literallayout>
</para>
<para>Next, you create a device called <filename>/dev/ft0</filename> by going into
<filename>/dev</filename> and run the following command:</para>
<para>
<literallayout> sh ./MAKEDEV ft0
</literallayout>
</para>
<para>for the first device. <emphasis remap=tt>ft1</emphasis> for a second one and so on.</para>
<para>You will have a device called <filename>/dev/ft0</filename>, which you can
write to through a special program to manage it called
``<emphasis remap=tt>ft</emphasis>'' - see the man page on <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ft">ft</ulink>
for further details.</para>
<para>Versions previous to <option>-current</option> also had some trouble dealing
with bad tape media; if you have trouble where <emphasis remap=tt>ft</emphasis> seems to
go back and forth over the same spot, try grabbing the latest
version of <emphasis remap=tt>ft</emphasis> from <filename>/usr/src/sbin/ft</filename> in
<option>-current</option> and try that.</para>
</answer></qandaentry></qandaset>
</chapter>
<chapter
id="admin">
<title>System Administration</title>
<qandaset><qandaentry><question>
<para>Where are the system start-up configuration files?</para></question><answer>
<para>From 2.0.5R to 2.2.1R, the primary configuration file is
<filename>/etc/sysconfig</filename>. All the options are to be specified in
this file and other files such as <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?rc">/etc/rc</ulink> and
<filename>/etc/netstart</filename> just include it.</para>
<para>Look in the <filename>/etc/sysconfig</filename> file and change the value to
match your system. This file is filled with comments to show what
to put in there.</para>
<para>In post-2.2.1 and 3.0, <filename>/etc/sysconfig</filename> was renamed
to a more self-describing <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?rc.conf(5)">rc.conf</ulink>
file and the syntax cleaned up a bit in the process.
<filename>/etc/netstart</filename> was also renamed to <filename>/etc/rc.network</filename>
so that all files could be copied with a <command><ulink URL="http://www.FreeBSD.org/cgi/man.cgi?cp">cp</ulink> /usr/src/etc/rc*
/etc</command> command.</para>
<para><filename>/etc/rc.local</filename> is here as always and may be used to
start up additional local services like <ulink URL="http://www.FreeBSD.org/cgi/ports.cgi?^inn">INN</ulink>
or set custom options.</para>
<para>The <filename>/etc/rc.serial</filename> is for serial port initialization
(e.g. locking the port characteristics, and so on.).</para>
<para>The <filename>/etc/rc.i386</filename> is for Intel-specifics settings, such
as iBCS2 emulation or the PC system console configuration.</para>
<para>Starting with 2.1.0R, you can also have "local" startup files in a
directory specified in <filename>/etc/sysconfig</filename> (or
<filename>/etc/rc.conf</filename>):</para>
<para>
<literallayout> # Location of local startup files.
local_startup=/usr/local/etc/rc.local.d
</literallayout>
</para>
<para>Each file ending in <filename>.sh</filename> will be executed in alphabetical order.</para>
<para>If you want to ensure a certain execution order without changing all
the file names, you can use a scheme similar to the following with
digits prepended to each file name to insure the ordering:</para>
<para>
<literallayout> 10news.sh
15httpd.sh
20ssh.sh
</literallayout>
</para>
<para>It can be seen as ugly (or SysV :-)) but it provides a simple and
regular scheme for locally-added packages without resorting to
magical editing of <filename>/etc/rc.local</filename>. Many of the ports/packages
assume that <filename>/usr/local/etc/rc.d</filename> is a local startup directory.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How do I add a user easily?</para></question><answer>
<para>Use the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?adduser">adduser</ulink> command. For more complicated usage, the
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?pw">pw</ulink> command.</para>
<para>To remove the user again, use the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?rmuser">rmuser</ulink> command.</para>
</answer></qandaentry>
<qandaentry><question>
<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="../tutorials/diskformat/">www.FreeBSD.org</ulink>.</para>
</answer></qandaentry>
<qandaentry><question>
<para>I have a new removable drive, how do I use it?</para></question><answer>
<para>Whether it's a removable drive like a ZIP or an EZ drive (or
even a floppy, if you want to use it that way), or a new hard
disk, once it's 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's a ZIP drive or a floppy , you've already got a DOS
filesystem on it, you can use a command like this:</para>
<para>
<literallayout> mount -t msdos /dev/fd0c /floppy
</literallayout>
</para>
<para>if it's a floppy, or this:</para>
<para>
<literallayout> mount -t msdos /dev/da2s4 /zip
</literallayout>
</para>
<para>for a ZIP disk with the factory configuration.</para>
<para>For other disks, see how they're laid out using <emphasis remap=tt>fdisk</emphasis> or
<filename>/stand/sysinstall</filename>.</para>
<para>The rest of the examples will be for a ZIP drive on da2, the third
SCSI disk.</para>
<para>Unless it's a floppy, or a removable you plan on sharing with
other people, it's probably a better idea to stick a BSD file
system on it. You'll 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 <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?fdisk">fdisk</ulink> or <filename>/stand/sysinstall</filename>, or for a small
drive that you don't 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>
<para>
<literallayout> dd if=/dev/zero of=/dev/rda2 count=2
disklabel -Brw sd2 auto
</literallayout>
</para>
<para>You can use disklabel or <filename>/stand/sysinstall</filename> to create multiple
BSD partitions. You'll certainly want to do this if you're adding
swap space on a fixed disk, but it's probably irrelevant on a
removable drive like a ZIP.</para>
<para>Finally, create a new file system, this one's on our ZIP drive
using the whole disk:</para>
<para>
<literallayout> newfs /dev/rda2c
</literallayout>
</para>
<para>and mount it:</para>
<para>
<literallayout> mount /dev/da2c /zip
</literallayout>
</para>
<para>and it's probably a good idea to add a line like this to
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?fstab">/etc/fstab</ulink> so you can just type "mount /zip" in the
future:</para>
<para>
<literallayout> /dev/da2c /zip ffs rw,noauto 0 0
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<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 "E" partition as the
second DOS partition on the second SCSI drive, you need to create
the special files for "slice 5" in /dev, then mount /dev/da1s5:</para>
<para>
<literallayout> # cd /dev
# ./MAKEDEV sd1s5
# mount -t msdos /dev/da1s5 /dos/e
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>Can I mount other foreign filesystems under FreeBSD?</para></question><answer>
<para><emphasis remap=bf> Digital UNIX</emphasis> 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>
<para><emphasis remap=bf> Linux</emphasis>: 2.2 and later have support for <emphasis remap=bf>ext2fs</emphasis> partitions.
See <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?mount_ext2fs">mount_ext2fs</ulink> for more information.</para>
<para><emphasis remap=bf> NT</emphasis>: A read-only NTFS driver exists for FreeBSD. For more
information, see this tutorial by Mark Ovens at
<ulink URL="http://www.users.globalnet.co.uk/~markov/ntfs_install.html">http://www.users.globalnet.co.uk/~markov/ntfs_install.html</ulink>.</para>
<para>Any other information on this subject would be appreciated.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How can I use the NT 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/NT
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>
<para>
<literallayout> [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"
</literallayout>
</para>
<para>This procedure assumes that DOS, NT, FreeBSD, or whatever
have been installed into their respective fdisk partitions on the
<emphasis remap=bf>same</emphasis> disk. In my case DOS &amp; NT are in the first fdisk
partition and FreeBSD is in the second. I also installed FreeBSD
to boot from its native partition, <emphasis remap=bf>not</emphasis> the disk MBR.</para>
<para>Mount a DOS-formatted floppy (if you've converted to NTFS) or the
FAT partition, under, say, <filename>/mnt</filename>.</para>
<para>
<literallayout> dd if=/dev/rda0a of=/mnt/bootsect.bsd bs=512 count=1
</literallayout>
</para>
<para>Reboot into DOS or NT. NTFS users copy the <filename>bootsect.bsd</filename>
and/or the <filename>bootsect.lnx</filename> file from the floppy to
<emphasis remap=tt>C:\</emphasis>. Modify the attributes (permissions) on
<filename>boot.ini</filename> with:</para>
<para>
<literallayout> attrib -s -r c:\boot.ini
</literallayout>
</para>
<para>Edit to add the appropriate entries from the example
<filename>boot.ini</filename> above, and restore the attributes:</para>
<para>
<literallayout> attrib +s +r c:\boot.ini
</literallayout>
</para>
<para>If FreeBSD is booting from the MBR, restore it with the DOS
``<emphasis remap=tt>fdisk</emphasis>'' command after you reconfigure them to boot from their
native partitions.</para>
</answer></qandaentry>
<qandaentry><question>
<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>:
<literallayout> other=/dev/hda2
table=/dev/hda
label=FreeBSD
</literallayout>
(the above assumes that your FreeBSD slice is known to Linux as
<filename>/dev/hda2</filename>; tailor to suit your setup). Then,
run <emphasis remap=tt>lilo</emphasis> as root 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:
<literallayout> other=/dev/dab4
table=/dev/dab
loader=/boot/chain.b
label=FreeBSD
</literallayout>
</para>
<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:
<literallayout> Boot: 1:da(0,a)/kernel
</literallayout>
</para>
<para>On FreeBSD 2.2.5 and later, you can configure <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?boot(8)">boot(8)</ulink>
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>
<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're running Windows-95 and Linux this is recommended anyway,
to make it simpler to get Linux booting again if you should need
to reinstall Windows95 (which is a Jealous Operating System, and
will bear no other Operating Systems in the Master Boot Record).</para>
</answer></qandaentry>
<qandaentry><question>
<para> Will a ``dangerously dedicated'' disk endanger my health?
</para></question><answer>
<para><anchor id="dedicate">The installation procedure allows you to chose
two different methods in partitioning your harddisk(s). The default way
makes it compatible with other operating systems on the same machine,
by using fdisk table entries (called ``slices'' 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 ``dangerous''? A disk in this mode
doesn't 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 ``dangerously dedicated'' disk's layout
is known to confuse many BIOSsen, including those from AWARD
(eg. 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 isn't a complete list, there are more.
Symptoms of this confusion include the "read error" message
printed by the FreeBSD bootstrap when it can't 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. ``Dangerously dedicated'' mode's origins lie
in a desire to avoid one of the most common problems plaguing
new FreeBSD installers - matching the BIOS ``geometry'' numbers
for a disk to the disk itself.</para>
<para>``Geometry'' 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 won't be able to boot.</para>
<para>``Dangerously dedicated'' mode tries to work around this
by making the problem simpler. In some cases, it gets it right.
But it's 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 ``DD'' mode when you're
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 ``-v'' at the
``boot:'' prompt, or using ``boot -v'' in the loader. Just
before the installer starts, the kernel will print a list of
BIOS geometries. Don't 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're slicing up your disk, check that the disk geometry
displayed in the FDISK screen is correct (ie. it matches the BIOS
numbers); if it's wrong, use the ``g'' key to fix it. You may have
to do this if there's 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're going to boot from; FreeBSD
will sort itself out just fine with any other disks you may have.</para>
<para>Once you've 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 ``DD'' mode at all. If, however,
you are still greeted with the dreaded ``read error'' message
when you try to boot, it's time to cross your fingers and
go for it - there's nothing left to lose.</para>
<para>To return a ``dangerously dedicated'' 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>
<para>
<literallayout> dd if=/dev/zero of=/dev/rda0 count=15
</literallayout>
</para>
<para>Alternatively, the undocumented DOS ``feature''</para>
<para>
<literallayout> fdisk /mbr
</literallayout>
</para>
<para>will to install a new master boot record as well, thus clobbering the
BSD bootstrap.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How can I add more swap space?</para></question><answer>
<para>The best way is to increase the size of your swap partition, or
take advantage of this convenient excuse to add another disk. The
general rule of thumb is to have around 2x the swap space as you have
main memory. However, if you have a very small amount of main memory
you may want to configure swap beyond that. It is also a good idea
to configure sufficient swap relative to anticipated future memory
upgrades so you do not have to futz with your swap configuration later.</para>
<para>Adding swap onto a separate disk makes things faster than
simply adding swap onto the same disk. As an example, if you
are compiling source located on one disk, and the swap is on
another disk, this is much faster than both swap and compile
on the same disk. This is true for SCSI disks specifically.</para>
<para>When you have several disks, configuring a swap partition on
each one is usually beneficial, even if you wind up putting swap on a
work disk. Typically, each fast disk in your system should have some
swap configured. FreeBSD supports up to 4 interleaved swap devices by
default. When configuring multiple swap partitions you generally
want to make them all about the same size, but people sometimes make
their primary swap parition larger in order to accomodate a kernel
core dump. Your primary swap partition must be at least as large as
main memory in order to be able to accomodate a kernel core.</para>
<para>IDE drives are not able to allow access to both drives on
the same channel at the same time (FreeBSD doesn't support mode 4, so
all IDE disk I/O is ``programmed''). I would still suggest putting
your swap on a separate drive however. The drives are so cheap,
it is not worth worrying about.</para>
<para>Swapping over NFS is only recommended if you do not have a local
disk to swap to. Swapping over NFS is slow and inefficient in FreeBSD
releases prior to 4.x, but reasonably fast in releases greater or
equal to 4.0. Even so, it will be limited to the network bandwidth
available and puts an additional burden on the NFS server.</para>
<para>Here is an example for 64Mb vn-swap (<filename>/usr/swap0</filename>, though
of course you can use any name that you want).</para>
<para>Make sure your kernel was built with the line</para>
<para>
<literallayout> pseudo-device vn 1 #Vnode driver (turns a file into a device)
</literallayout>
</para>
<para>in your config-file. The GENERIC kernel already contains this.</para>
<para>
<orderedlist>
<listitem>
<para>create a vn-device
<literallayout> cd /dev
sh ./MAKEDEV vn0
</literallayout>
</para>
</listitem>
<listitem>
<para>create a swapfile (<filename>/usr/swap0</filename>)
<literallayout> dd if=/dev/zero of=/usr/swap0 bs=1024k count=64
</literallayout>
</para>
</listitem>
<listitem>
<para>set proper permissions on (<filename>/usr/swap0</filename>)
<literallayout> chmod 0600 /usr/swap0
</literallayout>
</para>
</listitem>
<listitem>
<para>enable the swap file in <filename>/etc/rc.conf</filename>
<literallayout> swapfile="/usr/swap0" # Set to name of swapfile if aux swapfile desired.
</literallayout>
</para>
</listitem>
<listitem>
<para>reboot the machine</para>
</listitem>
</orderedlist>
</para>
<para>To enable the swap file immediately, type</para>
<para>
<literallayout> vnconfig -ce /dev/vn0c /usr/swap0 swap
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>I'm having problems 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="../handbook/printing.html">Handbook entry on printing.</ulink></para>
</answer></qandaentry>
<qandaentry><question>
<para>The keyboard mappings are wrong for my system.</para></question><answer>
<para>The kbdcontrol program has an option to load a keyboard map file.
Under <filename>/usr/share/syscons/keymaps</filename> are a number of map
files. Choose the one relevant to your system and load it.</para>
<para>
<literallayout> kbdcontrol -l uk.iso
</literallayout>
</para>
<para>Both the <filename>/usr/share/syscons/keymaps</filename> and the <filename>.kbd</filename>
extension are assumed by
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?kbdcontrol">kbdcontrol</ulink>.</para>
<para>This can be configured in <filename>/etc/sysconfig</filename> (or <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?rc.conf(5)">rc.conf</ulink>).
See the appropriate comments in this file.</para>
<para>In 2.0.5R and later, everything related to text fonts, keyboard
mapping is in <filename>/usr/share/examples/syscons</filename>.</para>
<para>The following mappings are currently supported:</para>
<para>
<itemizedlist>
<listitem>
<para>Belgian ISO-8859-1 </para>
</listitem>
<listitem>
<para>Brazilian 275 keyboard Codepage 850 </para>
</listitem>
<listitem>
<para>Brazilian 275 keyboard ISO-8859-1 </para>
</listitem>
<listitem>
<para>Danish Codepage 865 </para>
</listitem>
<listitem>
<para>Danish ISO-8859-1 </para>
</listitem>
<listitem>
<para>French ISO-8859-1 </para>
</listitem>
<listitem>
<para>German Codepage 850 </para>
</listitem>
<listitem>
<para>German ISO-8859-1 </para>
</listitem>
<listitem>
<para>Italian ISO-8859-1 </para>
</listitem>
<listitem>
<para>Japanese 106 </para>
</listitem>
<listitem>
<para>Japanese 106x </para>
</listitem>
<listitem>
<para>Latin American </para>
</listitem>
<listitem>
<para>Norwegian ISO-8859-1 </para>
</listitem>
<listitem>
<para>Polish ISO-8859-2 (programmer's) </para>
</listitem>
<listitem>
<para>Russian Codepage 866 (alternative) </para>
</listitem>
<listitem>
<para>Russian koi8-r (shift) </para>
</listitem>
<listitem>
<para>Russian koi8-r </para>
</listitem>
<listitem>
<para>Spanish ISO-8859-1 </para>
</listitem>
<listitem>
<para>Swedish Codepage 850 </para>
</listitem>
<listitem>
<para>Swedish ISO-8859-1 </para>
</listitem>
<listitem>
<para>Swiss-German ISO-8859-1 </para>
</listitem>
<listitem>
<para>United Kingdom Codepage 850 </para>
</listitem>
<listitem>
<para>United Kingdom ISO-8859-1 </para>
</listitem>
<listitem>
<para>United States of America ISO-8859-1 </para>
</listitem>
<listitem>
<para>United States of America dvorak </para>
</listitem>
<listitem>
<para>United States of America dvorakx </para>
</listitem>
</itemizedlist>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>I can't get user quotas to work properly.</para></question><answer>
<para>
<orderedlist>
<listitem>
<para>Don't turn on quotas on '/',
</para>
</listitem>
<listitem>
<para>Put the quota file on the file system that the quotas are
to be enforced on. ie:
<literallayout> FS QUOTA FILE
/usr /usr/admin/quotas
/home /home/admin/quotas
...
</literallayout>
</para>
</listitem>
</orderedlist>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>What's inappropriate about my ccd?</para></question><answer>
<para>The symptom of this is:</para>
<para>
<literallayout> # ccdconfig -C
ccdconfig: ioctl (CCDIOCSET): /dev/ccd0c: Inappropriate file type or format
#
</literallayout>
</para>
<para>This usually happens when you are trying to concatenate the
`c' partitions, which default to type `unused'. 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
`4.2BSD'.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Why can't I edit the disklabel on my ccd?</para></question><answer>
<para>The symptom of this is:</para>
<para>
<literallayout> # disklabel ccd0
(it prints something sensible here, so let's try to edit it)
# disklabel -e ccd0
(edit, save, quit)
disklabel: ioctl DIOCWDINFO: No disk label on disk;
use "disklabel -r" to install initial label
#
</literallayout>
</para>
<para>This is because the disklabel returned by ccd is actually a
`fake' one that is not really on the disk. You can solve
this problem by writing it back explicitly, as in:</para>
<para>
<literallayout> # disklabel ccd0 &gt; /tmp/disklabel.tmp
# disklabel -Rr ccd0 /tmp/disklabel.tmp
# disklabel -e ccd0
(this will work now)
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>Does FreeBSD support System V IPC primitives?</para></question><answer>
<para>Yes, FreeBSD supports System V-style IPC. This includes shared
memory, messages and semaphores. You need to add the following
lines to your kernel config to enable them.</para>
<para>
<literallayout> options SYSVSHM
options "SHMMAXPGS=64" # 256Kb of sharable memory
options SYSVSEM # enable for semaphores
options SYSVMSG # enable for messaging
</literallayout>
</para>
<para>Recompile and install.</para>
<para><emphasis remap=bf>NOTE:</emphasis> You may need to increase SHMMAXPGS to some
ridiculous number like 4096 (16M!) if you want to run
GIMP. 256Kb is plenty for X11R6 shared memory.</para>
</answer></qandaentry>
<qandaentry><question
id="uucpmail">
<para> How do I use sendmail for mail delivery with UUCP?
</para></question><answer>
<para>The sendmail configuration that ships with FreeBSD is
suited for sites that connect directly to the Internet.
Sites that wish to exchange their mail via UUCP must install
another sendmail configuration file.</para>
<para>Tweaking <filename>/etc/sendmail.cf</filename> manually is considered
something for purists. Sendmail version 8 comes with a
new approach of generating config files via some
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?m4">m4</ulink> preprocessing, where the actual hand-crafted configuration
is on a higher abstraction level. You should use the
configuration files under</para>
<para>
<literallayout> /usr/src/usr.sbin/sendmail/cf
</literallayout>
</para>
<para>If you didn't install your system with full sources, the sendmail
config stuff has been broken out into a separate source distribution
tarball just for you. Assuming you've got your CD-ROM mounted, do:</para>
<para>
<literallayout> cd /usr/src
tar -xvzf /cdrom/dists/src/ssmailcf.aa
</literallayout>
</para>
<para>Don't panic, this is only a few hundred kilobytes in size.
The file <acronym>README</acronym> in the <emphasis remap=tt>cf</emphasis> directory can
serve as a basic introduction to m4 configuration.</para>
<para>For UUCP delivery, you are best advised to use the
<emphasis>mailertable</emphasis> feature. This constitutes a database
that sendmail can use to base its routing decision upon.</para>
<para>First, you have to create your <filename>.mc</filename> file. The
directory <filename>/usr/src/usr.sbin/sendmail/cf/cf</filename> is the
home of these files. Look around, there are already a few
examples. Assuming you have named your file <filename>foo.mc</filename>,
all you need to do in order to convert it into a valid
<filename>sendmail.cf</filename> is:</para>
<para>
<literallayout> cd /usr/src/usr.sbin/sendmail/cf/cf
make foo.cf
cp foo.cf /etc/sendmail.cf
</literallayout>
</para>
<para>A typical <filename>.mc</filename> file might look like:</para>
<para>
<literallayout> include(`../m4/cf.m4')
VERSIONID(`Your version number')
OSTYPE(bsd4.4)
FEATURE(nodns)
FEATURE(nocanonify)
FEATURE(mailertable)
define(`UUCP_RELAY', your.uucp.relay)
define(`UUCP_MAX_SIZE', 200000)
MAILER(local)
MAILER(smtp)
MAILER(uucp)
Cw your.alias.host.name
Cw youruucpnodename.UUCP
</literallayout>
</para>
<para>The <emphasis>nodns</emphasis> and <emphasis>nocanonify</emphasis> features will
prevent any usage of the DNS during mail delivery. The
<symbol>UUCP_RELAY</symbol> clause is needed for bizarre reasons,
don't ask. Simply put an Internet hostname there that
is able to handle .UUCP pseudo-domain addresses; most likely,
you will enter the mail relay of your ISP there.</para>
<para>Once you've got this, you need this file called
<filename>/etc/mailertable</filename>. A typical example of this
gender again:</para>
<para>
<literallayout> #
# makemap hash /etc/mailertable.db &lt; /etc/mailertable
#
horus.interface-business.de uucp-dom:horus
.interface-business.de uucp-dom:if-bus
interface-business.de uucp-dom:if-bus
.heep.sax.de smtp8:%1
horus.UUCP uucp-dom:horus
if-bus.UUCP uucp-dom:if-bus
. uucp-dom:sax
</literallayout>
</para>
<para>As you can see, this is part of a real-life file. The first
three lines handle special cases where domain-addressed mail
should not be sent out to the default route, but instead to
some UUCP neighbor in order to ``shortcut'' the delivery
path. The next line handles mail to the local Ethernet
domain that can be delivered using SMTP. Finally, the UUCP
neighbors are mentioned in the .UUCP pseudo-domain notation,
to allow for a ``uucp-neighbor!recipient'' override of the
default rules. The last line is always a single dot, matching
everything else, with UUCP delivery to a UUCP neighbor that
serves as your universal mail gateway to the world. All of
the node names behind the <emphasis remap=tt>uucp-dom:</emphasis> keyword must
be valid UUCP neighbors, as you can verify using the
command <emphasis remap=tt>uuname</emphasis>.</para>
<para>As a reminder that this file needs to be converted into a
DBM database file before being usable, the command line to
accomplish this is best placed as a comment at the top of
the mailertable. You always have to execute this command
each time you change your mailertable.</para>
<para>Final hint: if you are uncertain whether some particular
mail routing would work, remember the <option>-bt</option> option to
sendmail. It starts sendmail in <emphasis>address test mode</emphasis>;
simply enter ``0 '', followed by the address you wish to
test for the mail routing. The last line tells you the used
internal mail agent, the destination host this agent will be
called with, and the (possibly translated) address. Leave
this mode by typing Control-D.</para>
<para>
<literallayout> j@uriah 191% sendmail -bt
ADDRESS TEST MODE (ruleset 3 NOT automatically invoked)
Enter &lt;ruleset&gt; &lt;address&gt;
&gt; 0 foo@interface-business.de
rewrite: ruleset 0 input: foo @ interface-business . de
...
rewrite: ruleset 0 returns: $# uucp-dom $@ if-bus $: foo \
&lt; @ interface-business . de &gt;
&gt; ^D
j@uriah 192%
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question
id="ispmail">
<para> How do I set up mail with a dialup connection to the 'net?
</para></question><answer>
<para>If you've got a statically assigned IP number, you should not
need to adjust anything from the default. Set your host name up
as your assigned internet name and sendmail will do the rest.</para>
<para>If you've got a dynamically assigned IP number and use a dialup
<emphasis remap=bf>ppp</emphasis> connection to the internet, you will probably be given a
mailbox on your ISPs mail server. Lets assume your ISPs domain is
<filename>myISP.com</filename>, and that your user name is <emphasis remap=tt>user</emphasis>. Lets also
assume you've called your machine <filename>bsd.home</filename> and that your ISP
has told you that you may use <filename>relay.myISP.com</filename> as a mail relay.</para>
<para>In order to retrieve mail from your mailbox, you'll need to
install a retrieval agent. <emphasis remap=bf>Fetchmail</emphasis> is a good choice as it
supports many different protocols. Usually, POP3 will be provided
by your ISP. If you've chosen to use user-ppp, you can automatically
fetch your mail when a connection to the 'net is established with the
following entry in <filename>/etc/ppp/ppp.linkup</filename>:</para>
<para>
<literallayout> MYADDR:
!bg su user -c fetchmail
</literallayout>
</para>
<para>If you are using <emphasis remap=tt>sendmail</emphasis> (as shown below) to deliver mail to
non-local accounts, put the command</para>
<para>
<literallayout> !bg su user -c "sendmail -q"
</literallayout>
</para>
<para>after the above shown entry. This forces sendmail to process your
mailqueue as soon as the connection to the 'net is established.</para>
<para>I'm assuming that you have an account for <emphasis remap=tt>user</emphasis> on <filename>bsd.home</filename>.
In the home directory of <emphasis remap=tt>user</emphasis> on <filename>bsd.home</filename>, create a
<filename>.fetchmailrc</filename> file:</para>
<para>
<literallayout> poll myISP.com protocol pop3 fetchall pass MySecret;
</literallayout>
</para>
<para>Needless to say, this file should not be readable by anyone except
<emphasis remap=tt>user</emphasis> as it contains the password <emphasis remap=tt>MySecret</emphasis>.</para>
<para>In order to send mail with the correct <emphasis remap=bf>from:</emphasis> header, you must
tell sendmail to use <email>user@myISP.com</email> rather than
<email>user@bsd.home</email>. You may also wish to tell sendmail to send all
mail via <filename>relay.myISP.com</filename>, allowing quicker mail transmission.</para>
<para>The following <filename>.mc</filename> file should suffice:</para>
<para>
<literallayout> VERSIONID(`bsd.home.mc version 1.0')
OSTYPE(bsd4.4)dnl
FEATURE(nouucp)dnl
MAILER(local)dnl
MAILER(smtp)dnl
Cwlocalhost
Cwbsd.home
MASQUERADE_AS(`myISP.com')dnl
FEATURE(allmasquerade)dnl
FEATURE(masquerade_envelope)dnl
FEATURE(nocanonify)dnl
FEATURE(nodns)dnl
define(SMART_HOST, `relay.myISP.com')
Dmbsd.home
define(`confDOMAIN_NAME',`bsd.home')dnl
define(`confDELIVERY_MODE',`deferred')dnl
</literallayout>
</para>
<para>Refer to the previous section for details of how to turn this
<filename>.mc</filename> file into a <filename>sendmail.cf</filename> file. Also, don't forget to
restart sendmail after updating sendmail.cf.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Eek! I forgot the root password!</para></question><answer>
<para>Don't Panic! Simply restart the system, type -s at the Boot: prompt
to enter Single User mode. At the question about the shell to use,
hit ENTER. You'll be dropped to a # 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 <emphasis remap=tt>passwd root</emphasis> to
change the root password then run <emphasis remap=tt>exit</emphasis>
to continue booting. </para>
</answer></qandaentry>
<qandaentry><question>
<para>How do I keep Control-Alt-Delete from rebooting the system?
</para></question><answer>
<para>Edit the keymap you are using for the console and replace the
<emphasis remap=tt>boot</emphasis> keywords with <emphasis remap=tt>nop</emphasis>. The default keymap is
<filename>/usr/share/syscons/keymaps/us.iso.kbd</filename>. You may have to instruct
<filename>/etc/rc.conf</filename> to load this keymap explicitly for the change to
take effect. Of course if you are using an alternate keymap for your
country, you should edit that one instead.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How do I reformat DOS text files to UNIX ones?</para></question><answer>
<para>Simply use this perl command:</para>
<para>
<literallayout>perl -i.bak -npe 's/\r\n/\n/g' file ...</literallayout>
</para>
<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 <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?tr">tr</ulink> command:</para>
<para>
<literallayout>tr -d '\r' &lt; dos-text-file &gt; unix-file</literallayout>
</para>
<para>dos-text-file is the file containing DOS text while
unix-file will contain the converted output. This can
be quite a bit faster than using perl.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How do I kill processes by name?</para></question><answer>
<para>Use <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?killall">killall</ulink>.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Why is su bugging me about not being in root's ACL?
</para></question><answer>
<para>The error comes from the Kerberos distributed authentication system.
The problem isn't 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>
<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'll assume on /cdrom) and run</para>
<para>
<literallayout>cd /cdrom/bin
./install.sh</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<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'll probably run
out of pseudoterminals. Here's how to add more:</para>
<para>
<orderedlist>
<listitem>
<para>Build and install a new kernel with the line
<literallayout> pseudo-device pty 256
</literallayout>
</para>
<para>in the configuration file.</para>
<para></para>
</listitem>
<listitem>
<para>Run the command
<literallayout> # cd /dev
# ./MAKEDEV pty{1,2,3,4,5,6,7}
</literallayout>
</para>
<para>to make 256 device nodes for the new terminals.</para>
<para></para>
</listitem>
<listitem>
<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
<literallayout> ttyqc none network
</literallayout>
</para>
<para>The order of the letter designations is <emphasis remap=tt>tty[pqrsPQRS][0-9a-v]</emphasis>,
using a regular expression. </para>
<para></para>
</listitem>
<listitem>
<para>Reboot the system with the new kernel and you're ready to go.</para>
</listitem>
</orderedlist>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>I can't create the snd0 device!</para></question><answer>
<para>The command to create the devices for the sound card is:
<literallayout> # cd /dev
# sh MAKEDEV snd0</literallayout>
</para>
<para>However, this does not make a device named <filename>/dev/snd0</filename>.
Instead, it creates devices named <emphasis remap=tt>mixer0</emphasis>, <emphasis remap=tt>audio0</emphasis>,
<emphasis remap=tt>dsp0</emphasis>, and others. Running the command is still necessary
to add sound devices, however.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How do I re-read /etc/rc.conf and re-start /etc/rc without
a reboot?</para></question><answer>
<para>Go into single user mode and than back to multi user mode.</para>
<para>On the console do:
<literallayout> # shutdown now
(Note: without -r or -h)
# return
# exit</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>What is a sandbox?</para></question><answer>
<para>&quot;Sandbox&quot; is a security term. It can mean two things:</para>
<para>
<itemizedlist>
<listitem>
<para></para>
<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></para>
<para>The process is said to be able to "play" 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></para>
<para>The walls might be a userid, for example. This is the
definition used in the security and named man pages.</para>
<para></para>
<para>Take the 'ntalk' service, for example (see
/etc/inetd.conf). This service used to run as userid
root. Now it runs as userid tty. The tty 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></para>
<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></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. "/" for that
process is this directory, not the real "/" of the
system).</para>
<para></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>
<para>UNIX implements two core sanboxes. 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 can not 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 patricular userid. If the
userid is not the root 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>
<para>How do I let ordinary users mount floppies 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> 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 777 /dev/fd0</userinput></screen>
</step>
<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>
</procedure>
<para>Users can now mount <filename>/dev/fd0</filename> 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>Unmounting the device is simple:</para>
<screen>&prompt.user; <userinput>umount <filename>~/my-mount-point</filename></userinput></screen>
<para>Another way to access MSDOS formatted media is to use the
<ulink
url="http://www.freebsd.org/cgi/ports.cgi?query=%5Emtools-&amp;stype=name">mtools</ulink> package in the ports collection.</para>
</answer>
</qandaentry>
</qandaset>
</chapter>
<chapter
id="x">
<title>The X Window System and Virtual Consoles</title>
<qandaset><qandaentry><question>
<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>Then read and follow the documentation on the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?manpath=xfree86&amp;query=xf86config">xf86config</ulink> tool, which assists you in configuring XFree86(tm)
for your particular graphics card/mouse/etc.</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="x-and-moused">
<para>Why doesn't my mouse 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 ``<filename>/dev/sysmouse</filename>''. All mouse events
received from the real mouse device are written to the sysmouse
device, using the MouseSystems protocol. If you wish to use your
mouse on one or more virtual consoles, <emphasis remap=bf>and</emphasis> use X, the
following configuration is recommended:</para>
<para>
<literallayout> /etc/rc.conf:
moused_type=ps/2 # or whatever your actual type is
moused_port=/dev/psm0 # or whatever your real port is
moused_flags=
/etc/XF86Config
Section Pointer
Protocol "MouseSystems"
Device "/dev/sysmouse"
.....
</literallayout>
</para>
<para>Some people prefer to use ``<filename>/dev/mouse</filename>'' under X. To
make this work, ``<filename>/dev/mouse</filename>'' should be linked to
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?sysmouse">/dev/sysmouse</ulink>:</para>
<para>
<literallayout> # cd /dev
# rm -f mouse
# ln -s sysmouse mouse
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>X Window menus and dialog boxes don't work right!</para></question><answer>
<para>Try turning off the Num Lock key.</para>
<para>If your Num Lock key is on by default at boot-time, you may add
the following line in the ``<emphasis remap=tt>Keyboard</emphasis>'' section of the
<emphasis remap=tt>XF86Config</emphasis> file.</para>
<para>
<literallayout> # Let the server do the NumLock processing. This should only be
# required when using pre-R6 clients
ServerNumLock
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<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 Alt-F2 (hold down the Alt
key and press the F2 key), and you will find a login prompt
waiting for you on the second ``virtual console''! When you
want to go back to the original session, do Alt-F1.</para>
<para>The default FreeBSD installation has three virtual consoles
enabled, and Alt-F1, Alt-F2, and Alt-F3 will switch between
these virtual consoles.</para>
<para>To enable more of them, edit <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ttys">/etc/ttys</ulink>
and add entries for ``<emphasis remap=tt>ttyv4</emphasis>'' to ``<emphasis remap=tt>ttyvc</emphasis>'' after the
comment on ``Virtual terminals'':</para>
<para>
<literallayout> # 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
</literallayout>
</para>
<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
``<emphasis remap=tt>secure</emphasis>'' to ``<emphasis remap=tt>insecure</emphasis>''.</para>
<para><emphasis remap=bf>IMPORTANT NOTE</emphasis> if you want to run an X server you <acronym>MUST</acronym>
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're 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>
<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>
<para>
<literallayout> ttyvb "/usr/libexec/getty Pc" cons25 on secure
</literallayout>
</para>
<para>to:</para>
<para>
<literallayout> ttyvb "/usr/libexec/getty Pc" cons25 off secure
</literallayout>
</para>
<para>If your keyboard has only ten function keys, you would end up with:</para>
<para>
<literallayout> ttyv9 "/usr/libexec/getty Pc" cons25 off secure
ttyva "/usr/libexec/getty Pc" cons25 off secure
ttyvb "/usr/libexec/getty Pc" cons25 off secure
</literallayout>
</para>
<para>(You could also just delete these lines.)</para>
<para>Once you have edited <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ttys">/etc/ttys</ulink>,
the next step is to make sure that you have enough virtual terminal
devices. The easiest way to do this is:</para>
<para>
<literallayout> # cd /dev
# ./MAKEDEV vty12 # For 12 devices
</literallayout>
</para>
<para>Next, the easiest (and cleanest) way to activate the virtual
consoles is to reboot. However, if you really don't want to
reboot, you can just shut down the X Window system and execute (as
<emphasis remap=tt>root</emphasis>):</para>
<para>
<literallayout> kill -HUP 1
</literallayout>
</para>
<para>It's imperative that you completely shut down X Window if it is
running, before running this command. If you don't, your system
will probably appear to hang/lock up after executing the kill
command.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How do I access the virtual consoles from X?</para></question><answer>
<para>If the console is currently displaying X Window, you can use
Ctrl-Alt-F1, etc. to switch to a virtual console. Note, however,
that once you've switched away from X Window to a virtual
terminal, you may use only the Alt- function key to switch to another
virtual terminal or back to X Window. You do not need to also press the
Ctrl key. If you use the control key to switch back to X on some
older releases, you can find your text console stuck in ``control-lock''
mode. Tap the control key to wake it up again.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How do I start XDM on boot?</para></question><answer>
<para>There are two schools of thought on how to start <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?manpath=xfree86&amp;query=xdm">xdm</ulink>. One school starts xdm from
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ttys">/etc/ttys</ulink> using the supplied example, while the other
simply runs xdm from <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?rc">rc.local</ulink> 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 doesn't. In both cases the result is the
same: X will popup 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, <emphasis remap=tt>xdm</emphasis> 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>A previous version of the FAQ said to add the
<emphasis remap=tt>vt</emphasis> you want X to use to the
<filename>/usr/X11R6/lib/X11/xdm/Xservers</filename> file. This is not necessary:
X will use the first free <emphasis remap=tt>vt</emphasis> it finds.</para>
</answer></qandaentry>
<qandaentry><question>
<para>When I run xconsole, I get ``Couldn't open console''.</para></question><answer>
<para>If you start <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?manpath=xfree86&amp;query=X">X</ulink> with <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?manpath=xfree86&amp;query=startx">startx</ulink>, the permissions on /dev/console will <emphasis remap=tt>not</emphasis> get
changed, resulting in things like <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?manpath=xfree86&amp;query=xterm">xterm -C</ulink> and <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?manpath=xfree86&amp;query=xconsole">xconsole</ulink> not working.</para>
<para>This is because of the way console permissions are set by default.
On a multi-user system, one doesn't 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
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?fbtab">fbtab</ulink>
file exists to solve such problems.</para>
<para>In a nutshell, make sure an uncommented line of the form</para>
<para>
<literallayout> /dev/ttyv0 0600 /dev/console
</literallayout>
</para>
<para>is in <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?fbtab(5)">/etc/fbtab</ulink> and it will ensure that whomever logs in on
<filename>/dev/ttyv0</filename> will own the console.</para>
</answer></qandaentry>
<qandaentry><question>
<para>My PS/2 mouse doesn't behave properly under X.</para></question><answer>
<para>Your mouse and the mouse driver may have somewhat become out of
synchronization.</para>
<para>In versions 2.2.5 and earlier, switching away from X to a
virtual terminal and getting back to X again may make them
re-synchronized. If the problem occurs often, you may add the
following option in your kernel configuration file and recompile it.</para>
<para>
<literallayout> options PSM_CHECKSYNC
</literallayout>
</para>
<para>See the section on <xref linkend="make-kernel" remap="building a kernel">
if you've no experience with building kernels.</para>
<para>With this option, there should be less chance of synchronization
problem between the mouse and the driver. If, however, you
still see the problem, click any mouse button while holding
the mouse still to re-synchronize the mouse and the driver.</para>
<para>Note that unfortunately this option may not work with all the
systems and voids the ``tap'' feature of the ALPS GlidePoint
device attached to the PS/2 mouse port.</para>
<para>In versions 2.2.6 and later, synchronization check is done
in a slightly better way and is standard in the PS/2 mouse driver.
It should even work with GlidePoint. (As the check code has become
a standard feature, PSM_CHECKSYNC option is not available in these
versions.) However, in rare case the driver may erroneously report
synchronization problem and you may see the kernel message:</para>
<para>
<literallayout> psmintr: out of sync (xxxx != yyyy)
</literallayout>
</para>
<para>and find your mouse doesn't seem to 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>
<para>
<literallayout> boot: -c
</literallayout>
</para>
<para>Then, in the <emphasis>UserConfig</emphasis> command line, type:</para>
<para>
<literallayout> UserConfig&gt; flags psm0 0x100
UserConfig&gt; quit
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>My PS/2 mouse from MouseSystems doesn't seem to 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 ``high resolution''
mode. Otherwise, the mouse cursor may jump to the upper-left
corner of the screen every so often.</para>
<para>Unfortunately there is no workaround for versions 2.0.X and
2.1.X. In versions 2.2 through 2.2.5, apply the following patch
to <filename>/sys/i386/isa/psm.c</filename> and rebuild the kernel. See the
section on <xref linkend="make-kernel" remap="building a kernel">
if you've no experience with building kernels.</para>
<para>
<literallayout>diff -u psm.c.orig psm.c
@@ -766,6 +766,8 @@
if (verbose &gt;= 2)
log(LOG_DEBUG, "psm%d: SET_DEFAULTS return code:%04x\n",
unit, i);
+ set_mouse_resolution(sc-&gt;kbdc, PSMD_RES_HIGH);
+
#if 0
set_mouse_scaling(sc-&gt;kbdc); /* 1:1 scaling */
set_mouse_mode(sc-&gt;kbdc); /* stream mode */
</literallayout>
</para>
<para>In versions 2.2.6 or later, 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>
<para>
<literallayout> boot: -c
</literallayout>
</para>
<para>Then, in the <emphasis>UserConfig</emphasis> command line, type:</para>
<para>
<literallayout> UserConfig&gt; flags psm0 0x04
UserConfig&gt; quit
</literallayout>
</para>
<para>See the previous section for another possible cause of mouse
problems.</para>
</answer></qandaentry>
<qandaentry><question>
<para>When building an X app, <emphasis remap=tt>imake</emphasis> can't find <filename>Imake.tmpl</filename>. Where is it?
</para></question><answer>
<para>Imake.tmpl is part of the Imake package, a standard X application building tool.
Imake.tmpl, 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>
<para>How do I reverse the mouse buttons?
</para></question><answer>
<para>Run the command <literal> xmodmap -e "pointer = 3 2 1"</literal> from your .xinitrc or .xsession.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How do I install a splash screen and where do I find them?
</para></question><answer>
<para>Just prior to the release of FreeBSD 3.1, a new feature was
added to allow the display of &quot;splash&quot; 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. Note that VESA support requires
the <emphasis remap=tt>VM86</emphasis> kernel option to be compiled into the
kernel. The actual VESA support can either be compiled directly
into the kernel with the <acronym>VESA</acronym> 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 FreeBSD. The files for this
changed prior to the release of FreeBSD 3.2, so there are now
two ways of loading a splash screen:</para>
<para>
<itemizedlist>
<listitem>
<para>FreeBSD 3.1
</para>
<para>The first step is to find a bitmap version of your splash
screen. Release 3.1 only supports Windows bitmap splash
screens. Once you've found your splash screen of choice
copy it to <filename>/boot/splash.bmp</filename>. Next, you need to
have a <filename>/boot/loader.rc</filename> file that contains the
following lines:</para>
<para>
<literallayout> load kernel
load -t splash_image_data /boot/splash.bmp
load splash_bmp
autoboot
</literallayout>
</para>
</listitem>
<listitem>
<para>FreeBSD 3.2+
</para>
<para>In addition to adding support for PCX splash screens,
FreeBSD 3.2 includes a nicer way of configuring the boot
process. If you wish, you can use the method listed above
for FreeBSD 3.1. If you do and you want to use PCX, replace
<symbol>splash_bmp</symbol> with <symbol>splash_pcx</symbol>. If,
on the other hand, you want to use the newer boot
configuration, you need to create a
<filename>/boot/loader.rc</filename> file that contains the
following lines:</para>
<para>
<literallayout> include /boot/loader.4th
start
</literallayout>
</para>
<para></para>
<para>and a <filename>/boot/loader.conf</filename> that contains the
following:</para>
<para>
<literallayout> splash_bmp_load="YES"
bitmap_load="YES"
</literallayout>
</para>
<para></para>
<para>This assumes you are using <filename>/boot/splash.bmp</filename>
for your splash screen. If you'd 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>
<para>
<literallayout> splash_pcx_load="YES"
bitmap_load="YES"
bitmap_name="/boot/splash.pcx"
</literallayout>
</para>
</listitem>
</itemizedlist>
</para>
<para>Now all you need is a splash screen. For that you can surf
on over to the gallery at <ulink URL="http://www.cslab.vt.edu/~jobaldwi/splash/">http://www.cslab.vt.edu/~jobaldwi/splash/</ulink>.</para>
</answer></qandaentry></qandaset>
</chapter>
<chapter
id="networking">
<title>Networking</title>
<qandaset><qandaentry><question>
<para>Where can I get information on ``diskless booting''?</para></question><answer>
<para>``Diskless booting'' 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="../handbook/diskless.html">the Handbook entry on diskless booting</ulink></para>
</answer></qandaentry>
<qandaentry><question>
<para> Can a FreeBSD box be used as a dedicated network router?
</para></question><answer>
<para>Internet standards and good engineering practice prohibit us from
providing packet forwarding by default in FreeBSD. You can
however enable this feature by changing the following variable to
<acronym>YES</acronym> in <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?rc.conf">rc.conf</ulink>:</para>
<para>
<literallayout> gateway_enable=YES # Set to YES if this host will be a gateway
</literallayout>
</para>
<para>This option will put the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?sysctl">sysctl</ulink> variable
<filename>net.inet.ip.forwarding</filename> to <emphasis remap=tt>1</emphasis>.</para>
<para>In most cases, you will also need to run a routing process to
tell other systems on your network about your router; FreeBSD
comes with the standard BSD routing daemon
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?routed">routed</ulink>, or for more complex situations you may want to try
<emphasis>GaTeD</emphasis> (available by FTP from <filename>ftp.gated.Merit.EDU</filename>) which
supports FreeBSD as of 3_5Alpha7.</para>
<para>It is our duty to warn you that, even when FreeBSD is configured
in this way, it does not completely comply with the Internet
standard requirements for routers; however, it comes close enough
for ordinary usage.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Can I connect my Win95 box to the Internet via FreeBSD?</para></question><answer>
<para>Typically, people who ask this question have two PC's at home, one
with FreeBSD and one with Win95; the idea is to use the FreeBSD
box to connect to the Internet and then be able to access the
Internet from the Windows95 box through the FreeBSD box. This
is really just a special case of the previous question.</para>
<para>There's a useful document available which explains how to set
FreeBSD up as a <ulink URL="http://www.ssimicro.com/~jeremyc/ppp.html">PPP Dialup Router</ulink></para>
<para><emphasis remap=bf>NOTE:</emphasis> This requires having at least two fixed IP addresses
available, and possibly three or more, depending on how much
work you want to go through to set up the Windows box. As an
alternative, if you don't have a fixed IP, you can use one of
the private IP subnets and install <emphasis remap=bf>proxies</emphasis> such as
<ulink URL="http://squid.nlanr.net/Squid/">SQUID</ulink> and
<ulink URL="http://www.tis.com/">the TIS firewall toolkit</ulink>
on your FreeBSD box.</para>
<para>See also the section on <xref linkend="natd" remap="natd">.</para>
</answer></qandaentry>
<qandaentry><question>
<para> Why does recompiling the latest BIND from ISC fail?
</para></question><answer>
<para>There is a conflict between the ``<filename>cdefs.h</filename>'' file in the
distribution and the one shipped with FreeBSD. Just remove
<filename>compat/include/sys/cdefs.h</filename>.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Does FreeBSD support SLIP and PPP?</para></question><answer>
<para>Yes. See the man pages for
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?slattach">slattach</ulink>, <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?sliplogin">sliplogin</ulink>,
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?pppd">pppd</ulink> and
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ppp">ppp</ulink>.
<emphasis remap=tt>pppd</emphasis> and <emphasis remap=tt>ppp</emphasis> provide support for both incoming and outgoing
connections. <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?sliplogin">Sliplogin</ulink> deals exclusively with incoming connections and
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?slattach">slattach</ulink> deals exclusively with outgoing connections.</para>
<para>These programs are described in the following sections of the
<ulink URL="../handbook/index.html">handbook</ulink>:</para>
<para>
<itemizedlist>
<listitem>
<para><ulink URL="../handbook/slips.html">Handbook entry on SLIP (server side)</ulink>
</para>
</listitem>
<listitem>
<para><ulink URL="../handbook/slipc.html">Handbook entry on SLIP (client side)</ulink>
</para>
</listitem>
<listitem>
<para><ulink URL="../handbook/ppp.html">Handbook entry on PPP (kernel version)</ulink>
</para>
</listitem>
<listitem>
<para><ulink URL="../handbook/ppp-and-slip.html#USERPPP">Handbook entry on PPP (user-mode version)</ulink></para>
</listitem>
</itemizedlist>
</para>
<para>If you only have access to the Internet through a "shell
account", you may want to have a look at the <ulink URL="http://www.FreeBSD.org/cgi/ports.cgi?^slirp">slirp</ulink>
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>If you have a local subnet (one or more local machines), but have
been allocated only a single IP number from your Internet provider
(or even if you receive a dynamic IP number), you may want to look at
the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?natd">natd</ulink>
program. <emphasis remap=tt>Natd</emphasis> allows you to connect an entire subnet to the
internet using only a single IP number.</para>
<para>The <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ppp">ppp</ulink> program has similar functionality built in via
the <option>-alias</option> switch. The <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?libalias">alias library</ulink>
is used in both cases.</para>
</answer></qandaentry>
<qandaentry><question>
<para>I can't create a <filename>/dev/ed0</filename> device!</para></question><answer>
<para>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>
<para>How can I setup Ethernet aliases?</para></question><answer>
<para>Add ``<literal>netmask 0xffffffff</literal>'' to your <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ifconfig">ifconfig</ulink>
command-line like the following:</para>
<para>
<literallayout> ifconfig ed0 alias 204.141.95.2 netmask 0xffffffff
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<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'll have to specify an
additional parameter on the
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ifconfig">ifconfig</ulink> command line. The
default port is ``<emphasis remap=tt>link0</emphasis>''. To use the AUI port instead of
the BNC one, use ``<emphasis remap=tt>link2</emphasis>''. These flags should be specified
using the ifconfig_* variables in <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?rc.conf">/etc/rc.conf</ulink>.</para>
</answer></qandaentry>
<qandaentry><question>
<para>I'm having problems with NFS to/from 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="../handbook/nfs.html">the Handbook entry on NFS</ulink>
for more information on this topic.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Why can't I 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>
<para>
<literallayout> mount -o -P linuxbox:/blah /mnt
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>Why can't I 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>
<para>
<literallayout> mount -o -P sunbox:/blah /mnt
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>I'm having problems talking PPP to NeXTStep machines.</para></question><answer>
<para>Try disabling the TCP extensions in <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?rc.conf">/etc/rc.conf</ulink> by
changing the following variable to NO:</para>
<para>
<literallayout> tcp_extensions=NO
</literallayout>
</para>
<para>Xylogic's Annex boxes are also broken in this regard and you must
use the above change to connect thru them.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How do I enable IP multicast support?</para></question><answer>
<para>Multicast host operations are fully supported in FreeBSD 2.0 and
later by default. If you want your box to run as a multicast router,
you will need to recompile your kernel with the <acronym>MROUTING</acronym>
option and run <emphasis remap=tt>mrouted</emphasis>. FreeBSD 2.2 and later will start
<emphasis remap=tt>mrouted</emphasis> at boot time if the flag <symbol>mrouted_enable</symbol> is set
to "YES" in <filename>/etc/rc.conf</filename>.</para>
<para>MBONE tools are available in their own ports category, mbone. If
you are looking for the conference tools <emphasis remap=tt>vic</emphasis> and <emphasis remap=tt>vat</emphasis>,
look there!</para>
<para>For more information, see the
<ulink URL="http://www.mbone.com/">Mbone Information Web</ulink>.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Which network cards are based on the DEC PCI chipset?</para></question><answer>
<para>Here is a list compiled by <ulink URL="mailto:gfoster@driver.nsta.org">Glen Foster</ulink>, with some more modern additions:</para>
<para>
<literallayout> Vendor Model
----------------------------------------------
ASUS PCI-L101-TB
Accton ENI1203
Cogent EM960PCI
Compex ENET32-PCI
D-Link DE-530
Dayna DP1203, DP2100
DEC DE435, DE450
Danpex EN-9400P3
JCIS Condor JC1260
Linksys EtherPCI
Mylex LNP101
SMC EtherPower 10/100 (Model 9332)
SMC EtherPower (Model 8432)
TopWare TE-3500P
Znyx (2.2.x) ZX312, ZX314, ZX342, ZX345, ZX346, ZX348
(3.x) ZX345Q, ZX346Q, ZX348Q, ZX412Q, ZX414, ZX442,
ZX444, ZX474, ZX478, ZX212, ZX214 (10mbps/hd)
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<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.bar.edu and you wish to reach
a host called ``mumble'' in the bar.edu domain, you will have to
refer to it by the fully-qualified domain name, ``mumble.bar.edu'',
instead of just ``mumble''.</para>
<para>Traditionally, this was allowed by BSD BIND resolvers. However
the current version of <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?named">bind</ulink> 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 <emphasis remap=tt>mumble</emphasis> must either be found
as <filename>mumble.foo.bar.edu</filename>, or it will be searched for
in the root domain.</para>
<para>This is different from the previous behavior, where the
search continued across <filename>mumble.bar.edu</filename>, and
<filename>mumble.edu</filename>. 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>
<para>
<literallayout> search foo.bar.edu bar.edu
</literallayout>
</para>
<para>instead of the previous</para>
<para>
<literallayout> domain foo.bar.edu
</literallayout>
</para>
<para>into your <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?resolv.conf">/etc/resolv.conf</ulink> file. However, make sure that the search order
does not go beyond the ``boundary between local and public
administration'', as RFC 1535 calls it.</para>
</answer></qandaentry>
<qandaentry><question>
<para>``Permission denied'' for all networking operations.</para></question><answer>
<para>If you have compiled your kernel with the <acronym>IPFIREWALL</acronym>
option, you need to be aware that the default policy as of
2.1.7R (this actually changed during 2.1-STABLE development)
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 root:</para>
<para>
<literallayout> ipfw add 65534 allow all from any to any
</literallayout>
</para>
<para>You can also set "firewall_type='open'" in <filename>/etc/rc.conf</filename>.</para>
<para>For further information on configuring a FreeBSD firewall,
see the <ulink URL="../handbook/firewalls.html">Handbook section</ulink>.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How much overhead does IPFW incur?</para></question><answer>
<para>The answer to this depends mostly on your rule set and processor
speed. For most applications dealing with ethernet and small
rule sets, the answer is, negligible. For those of you that need
actual measurements to satisfy your curiosity, read on.</para>
<para>The following measurements were made using 2.2.5-STABLE on
a 486-66. IPFW was modified to measure the time spent within
the <symbol>ip_fw_chk</symbol> routine, displaying the results to the console
every 1000 packets.</para>
<para>Two rule sets, each with 1000 rules were tested. The first set
was designed to demonstrate a worst case scenario by repeating the
rule:</para>
<para>
<literallayout> ipfw add deny tcp from any to any 55555
</literallayout>
</para>
<para>This demonstrates worst case by causing most of IPFW's packet
check routine to be executed before finally deciding that the
packet does not match the rule (by virtue of the port number).
Following the 999th iteration of this rule was an <emphasis remap=tt>allow ip
from any to any</emphasis>.</para>
<para>The second set of rules were designed to abort the rule
check quickly:</para>
<para>
<literallayout> ipfw add deny ip from 1.2.3.4 to 1.2.3.4
</literallayout>
</para>
<para>The nonmatching source IP address for the above rule causes
these rules to be skipped very quickly. As before, the 1000th
rule was an <emphasis remap=tt>allow ip from any to any</emphasis>.</para>
<para>The per-packet processing overhead in the former case was
approximately 2.703ms/packet, or roughly 2.7 microseconds per
rule. Thus the theoretical packet processing limit with these
rules is around 370 packets per second. Assuming 10Mbps ethernet
and a ~1500 byte packet size, we would only be able to achieve a
55.5% bandwidth utilization.</para>
<para>For the latter case each packet was processed in
approximately 1.172ms, or roughly 1.2 microseconds per rule.
The theoretical packet processing limit here would be about
853 packets per second, which could consume 10Mbps ethernet
bandwidth.</para>
<para>The excessive number of rules tested and the nature of those
rules do not provide a real-world scenario -- they were used only
to generate the timing information presented here. Here are a
few things to keep in mind when building an efficient rule set:</para>
<para>
<itemizedlist>
<listitem>
<para>Place an `established' rule early on to handle the
majority of TCP traffic. Don't put any <emphasis remap=tt>allow tcp</emphasis>
statements before this rule.
</para>
</listitem>
<listitem>
<para>Place heavily triggered rules earlier in the rule
set than those rarely used (<emphasis remap=bf>without changing the
permissiveness of the firewall</emphasis>, of course). You can see
which rules are used most often by examining the packet counting
statistics with <command>ipfw -a l</command>.
</para>
</listitem>
</itemizedlist>
</para>
</answer></qandaentry>
<qandaentry><question>
<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 'socket'
package, available in the ports tree in category 'sysutils'.
Simply replace the service's commandline to call socket instead, like so:</para>
<para>
<literallayout>ftp stream tcp nowait nobody /usr/local/bin/socket socket ftp.foo.com ftp</literallayout>
</para>
<para>where 'ftp.foo.com' and 'ftp' are the host and port to redirect to,
respectively.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Where can I get a bandwidth management tool?</para></question><answer>
<para>There are two bandwidth management tools available for FreeBSD.
<ulink URL="http://www.csl.sony.co.jp/person/kjc/programs.html">ALTQ</ulink> is available for free; Bandwidth Manager from
<ulink URL="http://www.etinc.com/">Emerging Technologies</ulink> is
a commercial product. </para>
</answer></qandaentry>
<qandaentry><question>
<para>Why do I get ``/dev/bpf0: device not configured"?</para></question><answer>
<para>The Berkeley Packet Filter <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?bpf">(bpf)</ulink> driver
needs to be enabled before running programs that utilize it.
Add this to your kernel config file and build a new kernel:</para>
<para>
<literallayout> pseudo-device bpfilter # Berkeley Packet Filter
</literallayout>
</para>
<para>Secondly, after rebooting you will have to create the device
node. This can be accomplished by a change to the <filename>/dev</filename>
directory, followed by the execution of:</para>
<para>
<informalexample>
<screen> # sh MAKEDEV bpf0
</screen>
</informalexample>
</para>
<para>Please see the <ulink URL="../handbook/kernelconfig-nodes.html">handbook's entry on device nodes</ulink> for more information
on creating devices.</para>
</answer></qandaentry></qandaset>
</chapter>
<chapter id="ppp">
<title>PPP</title>
<qandaset>
<qandaentry><question
id="userppp">
<para> I can't make ppp work. What am I doing wrong ?
</para></question><answer>
<para>You should first read the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ppp">ppp man page</ulink> and
the <ulink URL="../handbook/ppp-and-slip.html#USERPPP">ppp section of the handbook</ulink>. Enable logging with the command</para>
<para>
<literallayout> set log Phase Chat Connect Carrier lcp ipcp ccp command
</literallayout>
</para>
<para>This command may be typed at the <emphasis remap=bf>ppp</emphasis> command prompt or
it may be entered in the <filename>/etc/ppp/ppp.conf</filename> configuration file
(the start of the <emphasis remap=bf>default</emphasis> section is the best place to put it).
Make sure that <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?syslog.conf">/etc/syslog.conf</ulink> contains the lines</para>
<para>
<literallayout> !ppp
*.* /var/log/ppp.log
</literallayout>
</para>
<para>and that the file <filename>/var/log/ppp.log</filename> exists. You can
now find out a lot about what's going on from the log file.
Don't worry if it doesn't all make sense. If you need to
get help from someone, it may make sense to them.</para>
<para>If your version of ppp doesn't understand the "set log"
command, you should download the
<ulink URL="http://www.FreeBSD.org/~brian/">latest version</ulink>.
It will build on FreeBSD version 2.1.5 and higher.</para>
</answer>
</qandaentry>
<qandaentry><question>
<para>Ppp just hangs when I run it</para></question><answer>
<para>This is usually because your hostname won't resolve. The best
way to fix this is to make sure that <filename>/etc/hosts</filename> is
consoluted by your resolver first by editing <filename>/etc/host.conf</filename>
and putting the <emphasis remap=tt>hosts</emphasis> line first. Then, simply put an
entry in <filename>/etc/hosts</filename> for your local machine. If you have
no local network, change your <emphasis remap=tt>localhost</emphasis> line:</para>
<para>
<literallayout>127.0.0.1 foo.bar.com foo localhost
</literallayout>
</para>
<para>Otherwise, simply add another entry for your host. Consult the
relevant man pages for more details.</para>
<para>You should be able to successfully <command>ping -c1 `hostname`</command>
when you're done.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Ppp won't dial in -auto mode</para></question><answer>
<para>First, check that you've got a default route. By running <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?netstat">http://www.FreeBSD.org/cgi/man.cgi?netstat</ulink>
name="netstat -rn"&gt;, you should see two entries like this:</para>
<para>
<literallayout>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
</literallayout>
</para>
<para>This is assuming that you've used the addresses from the
handbook, the man page or from the ppp.conf.sample file.
If you haven't got a default route, it may be because you're
running an old version of <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ppp">ppp</ulink> that doesn't understand the
word <acronym>HISADDR</acronym> in the ppp.conf file. If your version of
<emphasis remap=bf>ppp</emphasis> is from before FreeBSD 2.2.5, change the</para>
<para>
<literallayout> add 0 0 HISADDR
</literallayout>
</para>
<para>line to one saying</para>
<para>
<literallayout> add 0 0 10.0.0.2
</literallayout>
</para>
<para>Another reason for the default route line being missing is that
you have mistakenly set up a default router in your
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?rc.conf">/etc/rc.conf</ulink> file (this file was called
<filename>/etc/sysconfig</filename> prior to release 2.2.2), and you have
omitted the line saying</para>
<para>
<literallayout> delete ALL
</literallayout>
</para>
<para>from <filename>ppp.conf</filename>. If this is the case, go back to the
<ulink URL="../handbook/ppp-and-slip.html#USERPPP-FINAL">Final system configuration</ulink> section of the handbook.</para>
</answer></qandaentry>
<qandaentry><question>
<para>What does "No route to host" mean</para></question><answer>
<para>This error is usually due to a missing</para>
<para>
<literallayout> MYADDR:
delete ALL
add 0 0 HISADDR
</literallayout>
</para>
<para>section in your <filename>/etc/ppp/ppp.linkup</filename> file. This is
only necessary if you have a dynamic IP address or don't know the
address of your gateway. If you're using interactive mode, you can
type the following after entering <emphasis remap=tt>packet mode</emphasis> (packet mode is
indicated by the capitalized <acronym>PPP</acronym> in the prompt):</para>
<para>
<literallayout> delete ALL
add 0 0 HISADDR
</literallayout>
</para>
<para>Refer to the <ulink URL="../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>
<para>My connection drops after about 3 minutes</para></question><answer>
<para>The default ppp timeout is 3 minutes. This can be adjusted
with the line</para>
<para>
<literallayout> set timeout NNN
</literallayout>
</para>
<para>where <acronym>NNN</acronym> is the number of seconds of inactivity before the
connection is closed. If <acronym>NNN</acronym> 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 <emphasis remap=bf>ppp</emphasis>s server socket using
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?telnet">telnet</ulink>
or <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?pppctl">pppctl</ulink>. Refer to the
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ppp">ppp</ulink> man
page for further details.</para>
</answer></qandaentry>
<qandaentry><question>
<para>My connection drops 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>
<para>
<literallayout> disable lqr
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>My connection drops 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's 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>
<para>
<literallayout> set dial "...... ATS10=10 OK ......"
</literallayout>
</para>
<para>Refer to your modem manual for details.</para>
</answer></qandaentry>
<qandaentry><question>
<para>My connection hangs after a random amount of time</para></question><answer>
<para>Many people experience hung connections with no apparent
explaination. 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
<emphasis remap=tt>ping</emphasis> to see if the <acronym>TD</acronym> light is flashing when you
transmit data. If it flashes (and the <acronym>RD</acronym> light doesn't), the
problem is with the remote end. If <acronym>TD</acronym> doesn't flash, the problem
is local. With an internal modem, you'll need to use the <emphasis remap=tt>set
server</emphasis> command in your <filename>ppp.conf</filename> file. When the hang occurs,
connect to ppp using pppctl. If your network connection suddenly
revives (ppp was revived due to the activity on the diagnostic socket)
or if you can't connect (assuming the <emphasis remap=tt>set socket</emphasis> command
succeeded at startup time), the problem is local. If you can connect
and things are still hung, enable local async logging with <emphasis remap=tt>set log
local async</emphasis> and use <emphasis remap=tt>ping</emphasis> 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>
</answer>
</qandaentry>
<qandaentry><question>
<para>The remote end isn't responding</para></question><answer>
<para>There's very little you can do about this. Most ISPs will
refuse to help if you're not running a Microsoft OS. You can
<emphasis remap=tt>enable lqr</emphasis> in your <filename>ppp.conf</filename> file, allowing ppp 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're running user-ppp....</para>
<para>First, try disabling all local compression by adding the
following to your configuration:</para>
<para>
<literallayout> disable pred1 deflate deflate24 protocomp acfcomp shortseq vj
deny pred1 deflate deflate24 protocomp acfcomp shortseq vj
</literallayout>
</para>
<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 amunition when you contact
your ISP (although it may make it apparent that you're 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 (``Memory fault, core dumped'' ?).</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 <ulink URL="mailto:brian@Awfulhak.org">brian@Awfulhak.org</ulink>, or even to ask your ISP to
contact me directly.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Ppp is hung</para></question><answer>
<para>Your best bet here is to rebuild ppp by adding <literal>CFLAGS+=-g</literal>
and <literal>STRIP=</literal> to the end of the Makefile, then doing a
<emphasis remap=tt>make clean &amp;&amp; make &amp;&amp; make install</emphasis>. When
ppp hangs, find the ppp process id with <emphasis remap=tt>ps ajxww | fgrep ppp</emphasis>
and run <emphasis remap=tt>gdb ppp PID</emphasis>. From the gdb prompt, you can then use
<emphasis remap=tt>bt</emphasis> to get a stack trace.</para>
<para>Send the results to <ulink URL="mailto:brian@Awfulhak.org">brian@Awfulhak.org</ulink>.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Nothing happens after the Login OK! message</para></question><answer>
<para>Prior to FreeBSD version 2.2.5, once the link was established,
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ppp">ppp</ulink> 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 <emphasis remap=bf>ppp</emphasis> to initiate
the LCP, use the following line:</para>
<para>
<literallayout> set openmode active
</literallayout>
</para>
<para><emphasis remap=bf>Note</emphasis>: 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 remap=bf>does</emphasis> do some harm.</para>
</answer></qandaentry>
<qandaentry><question>
<para>I keep seeing errors about magic being the same</para></question><answer>
<para>Occasionally, just after connecting, you may see messages in
the log that say "magic is the same". 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'll see repeated configure
requests and configure acknowledgements in the log file until
ppp 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 ppp from a
login script or program after login. I've also heard reports
of it happening consistently when using slirp. The reason is
that in the time taken between getty exiting and ppp starting, the
client-side ppp starts sending Line Control Protocol (LCP)
packets. Because ECHO is still switched on for the port on
the server, the client ppp sees these packets "reflect" back.</para>
<para>One part of the LCP negotiation is to establish a magic number
for each side of the link so that "reflections" 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 ppp sends LCP packets,
sees the same magic in the reflected packet and NAKs it. It
also sees the NAK reflect (which also means ppp 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 ppp starts on the server,
it's flooded with magic number changes and almost immediately
decides it's 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>
<para>
<literallayout> set openmode passive
</literallayout>
</para>
<para>This tells ppp 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>
<para>
<literallayout> set openmode active 3
</literallayout>
</para>
<para>This tells ppp to be passive for 3 seconds, and then to start
sending LCP requests. If the peer starts sending requests during
this period, ppp will immediately respond rather than waiting for
the full 3 second period.</para>
</answer></qandaentry>
<qandaentry><question>
<para> LCP negotiations continue 'till the connection is closed
</para></question><answer>
<para>There is currently an implementation mis-feature in <emphasis remap=bf>ppp</emphasis>
where it doesn't associate LCP, CCP &amp; IPCP responses with
their original requests. As a result, if one <emphasis remap=bf>ppp</emphasis>
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, <emphasis remap=bf>A</emphasis> and <emphasis remap=bf>B</emphasis>. <emphasis remap=bf>A</emphasis> starts
sending LCP requests immediately after connecting and <emphasis remap=bf>B</emphasis> takes
7 seconds to start. When <emphasis remap=bf>B</emphasis> starts, <emphasis remap=bf>A</emphasis> has sent 3 LCP
REQs. We're assuming the line has ECHO switched off, otherwise
we'd see magic number problems as described in the previous section.
<emphasis remap=bf>B</emphasis> sends a REQ, then an ACK to the first of <emphasis remap=bf>A</emphasis>'s REQs.
This results in <emphasis remap=bf>A</emphasis> entering the <acronym>OPENED</acronym> state and sending
and ACK (the first) back to <emphasis remap=bf>B</emphasis>. In the meantime, <emphasis remap=bf>B</emphasis> sends
back two more ACKs in response to the two additional REQs sent by
<emphasis remap=bf>A</emphasis> before <emphasis remap=bf>B</emphasis> started up. <emphasis remap=bf>B</emphasis> then receives the first
ACK from <emphasis remap=bf>A</emphasis> and enters the <acronym>OPENED</acronym> state. <emphasis remap=bf>A</emphasis> receives
the second ACK from <emphasis remap=bf>B</emphasis> and goes back to the <emphasis remap=bf>REQ-SENT</emphasis> 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,
<emphasis remap=bf>B</emphasis> receives the forth REQ from <emphasis remap=bf>A</emphasis>, resulting in it reverting
to the <emphasis remap=bf>ACK-SENT</emphasis> state and sending another (second) REQ and
(forth) ACK as per the RFC. <emphasis remap=bf>A</emphasis> gets the REQ, goes into
<emphasis remap=bf>REQ-SENT</emphasis> and sends another REQ. It immediately receives the
following ACK and enters <acronym>OPENED</acronym>.</para>
<para>This goes on 'till one side figures out that they're getting
nowhere and gives up.</para>
<para>The best way to avoid this is to configure one side to be
<emphasis remap=bf>passive</emphasis> - that is, make one side wait for the other to start
negotiating. This can be done with the</para>
<para>
<literallayout> set openmode passive
</literallayout>
</para>
<para>command. Care should be taken with this option. You should also
use the</para>
<para>
<literallayout> set stopped N
</literallayout>
</para>
<para>command to limit the amount of time that <emphasis remap=bf>ppp</emphasis> waits for the peer
to begin negotiations. Alternatively, the</para>
<para>
<literallayout> set openmode active N
</literallayout>
</para>
<para>command (where <emphasis remap=bf>N</emphasis> is the number of seconds to wait before
starting negotiations) can be used. Check the manual page for
details.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Ppp locks up shortly after connecting</para></question><answer>
<para>Prior to version 2.2.5 of FreeBSD, it was possible that your
link was disabled shortly after connection due to <emphasis remap=bf>ppp</emphasis>
mis-handling Predictor1 compression negotiation. This would
only happen if both sides tried to negotiate different
Compression Control Protocols (CCP). This problem is now
corrected, but if you're still running an old version of
<emphasis remap=bf>ppp</emphasis>, the problem can be circumvented with the line</para>
<para>
<literallayout> disable pred1
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>Ppp locks up when I shell out to test it</para></question><answer>
<para>When you execute the <emphasis remap=tt>shell</emphasis> or <emphasis remap=tt>!</emphasis> command, <emphasis remap=bf>ppp</emphasis>
executes a shell (or if you've passed any arguements, <emphasis remap=bf>ppp</emphasis>
will execute those arguements). 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 <emphasis remap=bf>ppp</emphasis> is waiting for the command
to complete.</para>
<para>If you wish to execute commands like this, use the
<emphasis remap=tt>!bg</emphasis> command instead. This will execute the given command
in the background, and ppp can continue to service the link.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Ppp over a null-modem cable never exits</para></question><answer>
<para>There is no way for <emphasis remap=bf>ppp</emphasis> 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>
<para>
<literallayout> enable lqr
</literallayout>
</para>
<para>LQR is accepted by default if negotiated by the peer.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Why does ppp dial for no reason in -auto mode</para></question><answer>
<para>If <emphasis remap=bf>ppp</emphasis> 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>
<para>
<literallayout> set log +tcp/ip
</literallayout>
</para>
<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 remap=bf>not</emphasis>
prevent <emphasis remap=bf>ppp</emphasis> from passing the packets through an established
connection), use the following:</para>
<para>
<literallayout> set dfilter 1 deny udp src eq 53
set dfilter 2 deny udp dst eq 53
set dfilter 3 permit 0/0 0/0
</literallayout>
</para>
<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,
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?sendmail">sendmail</ulink> 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 <xref linkend="ispmail" remap="Mail Configuration"> 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>
<para>
<literallayout> define(`confDELIVERY_MODE', `d')dnl
</literallayout>
</para>
<para>This will make sendmail queue everything until the queue is
run (usually, sendmail is invoked with ``-bd -q30m'', telling it
to run the queue every 30 minutes) or until a ``sendmail -q''
is done (perhaps from your ppp.linkup file).</para>
</answer></qandaentry>
<qandaentry><question>
<para>What do these CCP errors mean</para></question><answer>
<para>I keep seeing the following errors in my log file:</para>
<para>
<literallayout> CCP: CcpSendConfigReq
CCP: Received Terminate Ack (1) state = Req-Sent (6)
</literallayout>
</para>
<para>This is because ppp 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>
<para>
<literallayout> disable pred1
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>Ppp locks up during file transfers with IO errors</para></question><answer>
<para>Under FreeBSD 2.2.2 and before, there was a bug in the tun
driver that prevents incoming packets of a size larger than
the tun interface's MTU size. Receipt of a packet greater than
the MTU size results in an IO error being logged via syslogd.</para>
<para>The ppp specification says that an MRU of 1500 should
<emphasis remap=bf>always</emphasis> be accepted as a minimum, despite any LCP
negotiations, therefore it is possible that should you decrease
the MTU to less than 1500, your ISP will transmit packets of
1500 regardless, and you will tickle this non-feature - locking
up your link.</para>
<para>The problem can be circumvented by never setting an MTU of
less than 1500 under FreeBSD 2.2.2 or before.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Why doesn't ppp log my connection speed?</para></question><answer>
<para>In order to log all lines of your modem ``conversation'',
you must enable the following:</para>
<para>
<literallayout> set log +connect
</literallayout>
</para>
<para>This will make
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ppp">ppp</ulink>
log everything up until the last requested "expect" string.</para>
<para>If you wish to see your connect speed and are using PAP or CHAP
(and therefore don't have anything to "chat" after the CONNECT
in the dial script - no "set login" script), you must make sure that
you instruct ppp to "expect" the whole CONNECT line, something like
this:</para>
<para>
<literallayout> set dial "ABORT BUSY ABORT NO\\sCARRIER TIMEOUT 4 \"\" ATZ OK-ATZ-OK ATDT\\T TIMEOUT 60 CONNECT \\c \\n"
</literallayout>
</para>
<para>Here, we get our CONNECT, send nothing, then expect a line-feed,
forcing <emphasis remap=bf>ppp</emphasis> to read the whole CONNECT response.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Ppp ignores the `\' 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 <emphasis remap=tt>set phone "123 456 789"</emphasis> correctly
(and realize that the number is actually only <emphasis remap=bf>one</emphasis> argument.
In order to specify a ``"'' character, you must escape it using
a backslash (``\'').</para>
<para>When the chat interpreter parses each argument, it re-interprets
the argument in order to find any special escape sequences such
as ``\P'' or ``\T'' (see the man 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 ``\'' character to (say) your
modem, you'd need something like:</para>
<para>
<literallayout> set dial "\"\" ATZ OK-ATZ-OK AT\\\\X OK"
</literallayout>
</para>
<para>resulting in the following sequence:</para>
<para>
<literallayout> ATZ
OK
AT\X
OK
</literallayout>
</para>
<para>or</para>
<para>
<literallayout> set phone 1234567
set dial "\"\" ATZ OK ATDT\\T"
</literallayout>
</para>
<para>resulting in the following sequence:</para>
<para>
<literallayout> ATZ
OK
ATDT1234567
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>Ppp gets 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 ppp runs with an effective user id of 0,
the operating system will not write ppps core image to disk
before terminating it. If, however ppp <emphasis remap=bf>is</emphasis> actually
termating due to a segmentation violation or some other
signal that normally causes core to be dumped, <emphasis remap=bf>and</emphasis> you're
sure you're using the latest version (see the start of this
section), then you should do the following:</para>
<para>
<literallayout> $ tar xfz ppp-*.src.tar.gz
$ cd ppp*/ppp
$ echo STRIP= &gt;&gt;Makefile
$ echo CFLAGS+=-g &gt;&gt;Makefile
$ make clean all
$ su
# make install
# chmod 555 /usr/sbin/ppp
</literallayout>
</para>
<para>You will now have a debuggable version of ppp installed. You
will have to be root to run ppp as all of its privileges have
been revoked. When you start ppp, take a careful note of what
your current directory was at the time.</para>
<para>Now, if and when ppp receives the segmentation violation, it
will dump a core file called ppp.core. You should then do the
following:</para>
<para>
<literallayout> $ su
# gdb /usr/sbin/ppp ppp.core
(gdb) bt
.....
(gdb) f 0
.....
(gdb) i args
.....
(gdb) l
.....
</literallayout>
</para>
<para>All of this information should be given alongside your
question, making it possible to diagnose the problem.</para>
<para>If you're 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>
<para> The process that forces a dial in auto mode never connects
</para></question><answer>
<para>This was a known problem with <emphasis remap=bf>ppp</emphasis> set up to negotiate
a dynamic local IP number with the peer in auto mode. It is
fixed in the latest version - search the man page for <emphasis remap=bf>iface</emphasis>.</para>
<para>The problem was that when that initial program calls
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?connect">connect(2)</ulink>, 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. <emphasis remap=bf>Ppp</emphasis> then
reads the packet and establishes a connection. If, as a result
of <emphasis remap=bf>ppp</emphasis>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 aren't, 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 <emphasis remap=tt>:-)</emphasis> The current version of <emphasis remap=bf>ppp</emphasis> does this,
but most other implementations don't.</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
<emphasis remap=tt>iface-alias</emphasis> option in the latest version of <emphasis remap=bf>ppp</emphasis> is
doing (with the help of <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?libalias">libalias(3)</ulink>
and ppp's <option>-alias</option> switch) - it's maintaining all previous
interface addresses and aliasing 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. <emphasis remap=bf>Ppp</emphasis> 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 <emphasis remap=bf>ppp</emphasis> to change the source IP number, but only if
it's 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>
<para>Why don't most games work with the -alias switch</para></question><answer>
<para>The reason games and the like don't 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 packet alias software doesn't 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're having problems with, then either
run tcpdump on the tun interface of the gateway or enable ppp
tcp/ip logging (``set log +tcp/ip'') 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'll be dropped (that's 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 /etc/ppp/ppp.conf will make the software functional:</para>
<para>
<literallayout> alias port proto internalmachine:port port
</literallayout>
</para>
<para>where ``proto'' is either ``tcp'' or ``udp'',
``internalmachine'' is the machine that you want the packets
to be sent to and ``port'' is the destination port number of
the packets.</para>
<para>You won't 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 aren't consistent, there are three more
options:</para>
<para><emphasis remap=bf>1)</emphasis> Submit support in libalias. Examples of ``special
cases'' can be found in /usr/src/lib/libalias/alias_*.c (alias_ftp.c
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
``route'' 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>
<para><emphasis remap=bf>2)</emphasis> Use a proxy. The application may support socks5
for example, or (as in the ``cvsup'' case) may have a ``passive''
option that avoids ever requesting that the peer open connections
back to the local machine.</para>
<para><emphasis remap=bf>3)</emphasis> Redirect everything to the internal machine using
``alias addr''. This is the sledge-hammer approach.</para>
</answer>
</qandaentry>
<qandaentry><question>
<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, <emphasis remap=tt>internal</emphasis> should
be replaced with the IP number of the machine playing the game.</para>
<para>
<itemizedlist>
<listitem>
<para><emphasis remap=bf>Quake</emphasis>
</para>
<para><emphasis remap=tt>alias port udp internal:6112 6112</emphasis></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>
</itemizedlist>
</para>
<para>
<itemizedlist>
<listitem>
<para><emphasis remap=bf>Quake 2</emphasis>
</para>
<para><emphasis remap=tt>alias port udp internal:27901 27910</emphasis></para>
</listitem>
</itemizedlist>
</para>
<para>
<itemizedlist>
<listitem>
<para><emphasis remap=bf>Red Alert</emphasis>
</para>
<para><emphasis remap=tt>alias port udp internal:8675 8675</emphasis></para>
<para><emphasis remap=tt>alias port udp internal:5009 5009</emphasis></para>
</listitem>
</itemizedlist>
</para>
<para>
<itemizedlist>
<listitem>
<para><emphasis remap=bf>Half Life</emphasis>
</para>
<para><emphasis remap=tt>alias port udp internal:27005 27015</emphasis></para>
</listitem>
</itemizedlist>
</para>
<para>
<itemizedlist>
<listitem>
<para><emphasis remap=bf>PCAnywhere 8.0</emphasis>
</para>
<para><emphasis remap=tt>alias port udp internal:5632 5632</emphasis></para>
<para><emphasis remap=tt>alias port tcp internal:5631 5631</emphasis></para>
</listitem>
</itemizedlist>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>What are FCS errors ?</para></question><answer>
<para>FCS stands for <emphasis remap=bf>F</emphasis>rame <emphasis remap=bf>C</emphasis>heck <emphasis remap=bf>S</emphasis>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 <emphasis remap=tt>show hdlc</emphasis> 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've 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 remap=bf>must</emphasis> use
software flow control, use the command
<literal>set accmap 0x000a0000</literal> to tell <emphasis remap=bf>ppp</emphasis> to escape
the ^Q and ^S 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 <emphasis remap=tt>async</emphasis> 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's possible to
terminate ppp without dropping the line by using the
<emphasis remap=tt>close lcp</emphasis> command (a following <emphasis remap=tt>term</emphasis> 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><question>
<para>None of this helps - I'm desperate !</para></question><answer>
<para>If all else fails, send as much information as you can,
including your config files, how you're starting <emphasis remap=bf>ppp</emphasis>,
the relevant parts of your log file and the output of the
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?netstat">netstat -rn</ulink> command (before and after connecting) to the
<ulink URL="mailto:freebsd-questions@FreeBSD.org">freebsd-questions@FreeBSD.org</ulink> mailing list 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 <xref linkend="networking" remap="Networking"> section.</para>
<qandaset><qandaentry><question>
<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>
<para>
<literallayout> dmesg | grep sio
</literallayout>
</para>
<para>after your system's up and running.</para>
<para>Here's some example output from the above command:</para>
<para>
<literallayout> sio0 at 0x3f8-0x3ff irq 4 on isa
sio0: type 16550A
sio1 at 0x2f8-0x2ff irq 3 on isa
sio1: type 16550A
</literallayout>
</para>
<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 ``attached''
to the port.</para>
<para>The <acronym>GENERIC</acronym> kernel includes support for two serial ports
using the same irq and port address settings in the above
example. If these settings aren't right for your system, or if
you've added modem cards or have more serial ports than your
kernel is configured for, just reconfigure your kernel. See
section <xref linkend="make-kernel" remap="about building a kernel"> for
more details.</para>
</answer></qandaentry>
<qandaentry><question>
<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>
<para>I just upgraded to 2.0.5 and my <emphasis remap=tt>tty0X</emphasis> are missing!</para></question><answer>
<para>Don't worry, they have been merged with the <emphasis remap=tt>ttydX</emphasis> devices.
You'll have to change any old configuration files you have, though.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How do I access the serial ports on FreeBSD?</para></question><answer>
<para>The third serial port, <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?sio">sio2</ulink> (known as
COM3 in DOS), is on <filename>/dev/cuaa2</filename> for dial-out devices, and on
<filename>/dev/ttyd2</filename> for dial-in devices. What's the difference
between these two classes of devices?</para>
<para>You use <emphasis remap=tt>ttydX</emphasis> for dial-ins. When opening <filename>/dev/ttydX</filename>
in blocking mode, a process will wait for the corresponding
<emphasis remap=tt>cuaaX</emphasis> device to become inactive, and then wait
for the carrier detect line to go active. When you open the
<emphasis remap=tt>cuaaX</emphasis> device, it makes sure the serial port isn't already in
use by the <emphasis remap=tt>ttydX</emphasis> device. If the port's available, it
``steals'' it from the <emphasis remap=tt>ttydX</emphasis> device. Also, the <emphasis remap=tt>cuaXX</emphasis>
device doesn't care about carrier detect. With this scheme and
an auto-answer modem, you can have remote users log in and you
can still dialout with the same modem and the system will take
care of all the conflicts.</para>
</answer></qandaentry>
<qandaentry><question>
<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 <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?sio">sio</ulink> 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 <symbol>COM_MULTIPORT</symbol>
option.</para>
<para>The following example is for an AST 4-port serial card on irq 7:</para>
<para>
<literallayout> 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
</literallayout>
</para>
<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>
<para>Can FreeBSD handle multiport serial cards sharing irqs?</para></question><answer>
<para>Not yet. You'll have to use a different irq for each card.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Can I set the default serial parameters for a port?</para></question><answer>
<para>The <emphasis remap=tt>ttydX</emphasis> (or <emphasis remap=tt>cuaaX</emphasis>) device is the regular device
you'll want to open for your applications. When a process opens
the device, it'll have a default set of terminal I/O settings.
You can see these settings with the command</para>
<para>
<literallayout> stty -a -f /dev/ttyd1
</literallayout>
</para>
<para>When you change the settings to this device, the settings are in
effect until the device is closed. When it's reopened, it goes
back to the default set. To make changes to the default set, you
can open and adjust the settings of the ``initial state'' device.
For example, to turn on <acronym>CLOCAL</acronym> mode, 8 bits, and
<filename>XON/XOFF</filename> flow control by default for ttyd5, do:</para>
<para>
<literallayout> stty -f /dev/ttyid5 clocal cs8 ixon ixoff
</literallayout>
</para>
<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
<emphasis remap=tt>ttyd5</emphasis>. 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 ``lock state'' device.
For example, to lock the speed of <emphasis remap=tt>ttyd5</emphasis> to 57600 bps, do</para>
<para>
<literallayout> stty -f /dev/ttyld5 57600
</literallayout>
</para>
<para>Now, an application that opens <emphasis remap=tt>ttyd5</emphasis> 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 <emphasis remap=tt>root</emphasis>. The <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?MAKEDEV">MAKEDEV</ulink> script does <acronym>NOT</acronym> do this when it creates the
device entries.</para>
</answer></qandaentry>
<qandaentry><question>
<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'll 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>
<para>
<literallayout> AT &amp;C1 &amp;D3 &amp;K3 &amp;Q6 S0=1 &amp;W
</literallayout>
</para>
<para>See the section <xref linkend="direct-at" remap="on sending AT commands"> below for information on how to make these settings
without resorting to an MS-DOS terminal program.</para>
<para>Next, make an entry in <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ttys">/etc/ttys</ulink> 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>
<para>
<literallayout> ttyd1 "/usr/libexec/getty std.57600" dialup on insecure
</literallayout>
</para>
<para>This line indicates that the second serial port
(<filename>/dev/ttyd1</filename>) has a modem connected running at 57600 bps
and no parity (<emphasis remap=tt>std.57600</emphasis>, which comes from the file
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?gettytab">/etc/gettytab</ulink>). The terminal type for this port is
``dialup.'' The port is ``on'' and is ``insecure''---meaning
root logins on the port aren't allowed. For dialin ports like
this one, use the <emphasis remap=tt>ttydX</emphasis> entry.</para>
<para>It's common practice to use ``dialup'' as the terminal type.
Many users set up in their .profile or .login files a prompt for
the actual terminal type if the starting type is dialup. The
example shows the port as insecure. To become root on this port,
you have to login as a regular user, then ``<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?su">su</ulink>'' to
<emphasis remap=tt>root</emphasis>. If you use ``secure'' then <emphasis remap=tt>root</emphasis> can login in
directly.</para>
<para>After making modifications to <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ttys">/etc/ttys</ulink>, you
need to send a hangup or <acronym>HUP</acronym> signal to the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?init">init</ulink> process:</para>
<para>
<literallayout> kill -HUP 1
</literallayout>
</para>
<para>This forces the init process to reread <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ttys">/etc/ttys</ulink>. The
init process will then start getty processes on all ``on'' ports.
You can find out if logins are available for your port by typing</para>
<para>
<literallayout> ps -ax | grep '[t]tyd1'
</literallayout>
</para>
<para>You should see something like:</para>
<para>
<literallayout> 747 ?? I 0:00.04 /usr/libexec/getty std.57600 ttyd1
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>How can I connect a dumb terminal to my FreeBSD box?</para></question><answer>
<para>If you're using another computer as a terminal into your FreeBSD
system, get a null modem cable to go between the two serial
ports. If you're using an actual terminal, see its accompanying
instructions.</para>
<para>Then, modify <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ttys">/etc/ttys</ulink>, like above. For example, if you're hooking up a
WYSE-50 terminal to the fifth serial port, use an entry like this:</para>
<para>
<literallayout> ttyd4 "/usr/libexec/getty std.38400" wyse50 on secure
</literallayout>
</para>
<para>This example shows that the port on <filename>/dev/ttyd4</filename> has a
wyse50 terminal connected at 38400 bps with no parity
(<emphasis remap=tt>std.38400</emphasis> from <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?gettytab">/etc/gettytab</ulink>) and <emphasis remap=tt>root</emphasis> logins are allowed (secure).</para>
</answer></qandaentry>
<qandaentry><question>
<para>Why can't I run <emphasis remap=tt>tip</emphasis> or <emphasis remap=tt>cu</emphasis>?</para></question><answer>
<para>On your system, the programs <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?tip">tip</ulink> and <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?cu">cu</ulink> are probably
executable only by <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?uucp">uucp</ulink> and group <emphasis remap=tt>dialer</emphasis>. You can use the group <emphasis remap=tt>dialer</emphasis>
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 <emphasis remap=tt>tip</emphasis>
and <emphasis remap=tt>cu</emphasis> by typing:</para>
<para>
<literallayout> # chmod 4511 /usr/bin/cu
# chmod 4511 /usr/bin/tip
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>My stock Hayes modem isn't supported---what can I do?</para></question><answer>
<para>Actually, the man page for <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?tip">tip</ulink> is out of
date. There is a generic Hayes dialer already built in. Just use
``<literal>at=hayes</literal>'' in your <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?remote">/etc/remote</ulink> file.</para>
<para>The Hayes driver isn't smart enough to recognize some of the
advanced features of newer modems---messages like <acronym>BUSY</acronym>,
<emphasis remap=tt>NO DIALTONE</emphasis>, or <emphasis remap=tt>CONNECT 115200</emphasis> will just confuse it.
You should turn those messages off when you use <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?tip">tip</ulink> (using
<emphasis remap=tt>ATX0&amp;W</emphasis>).</para>
<para>Also, the dial timeout for <emphasis remap=tt>tip</emphasis> is 60 seconds. Your modem
should use something less, or else tip will think there's a
communication problem. Try <literal>ATS7=45&amp;W</literal>.</para>
<para>Actually, as shipped <emphasis remap=tt>tip</emphasis> doesn't 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 ``<emphasis remap=tt>#define HAYES 0</emphasis>'' to ``<emphasis remap=tt>#define HAYES
1</emphasis>''. Then ``<emphasis remap=tt>make</emphasis>'' and ``<emphasis remap=tt>make install</emphasis>''. 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's called a ``<emphasis remap=tt>direct</emphasis>'' entry in your
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?remote">/etc/remote</ulink> file. For example, if your modem's hooked
up to the first serial port, <filename>/dev/cuaa0</filename>, then put in the
following line:</para>
<para>
<literallayout> cuaa0:dv=/dev/cuaa0:br#19200:pa=none
</literallayout>
</para>
<para>Use the highest bps rate your modem supports in the br
capability. Then, type <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?tip">tip cuaa0</ulink> and
you'll be connected to your modem.</para>
<para>If there is no <filename>/dev/cuaa0</filename> on your system, do this:</para>
<para>
<literallayout> # cd /dev
# ./MAKEDEV cuaa0
</literallayout>
</para>
<para>Or use cu as root with the following command:</para>
<para>
<literallayout> # cu -l``line'' -s``speed''
</literallayout>
</para>
<para>with line being the serial port (e.g.<filename>/dev/cuaa0</filename>)
and speed being the speed (e.g.<emphasis remap=tt>57600</emphasis>). When you are done
entering the AT commands hit <emphasis remap=tt>~.</emphasis> to exit.</para>
</answer></qandaentry>
<qandaentry><question>
<para>The <email>@</email> sign for the pn capability doesn't work!</para></question><answer>
<para>The <email>@</email> sign in the phone number capability tells tip to look in
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?phones(5)">/etc/phones</ulink> for a phone number. But the <email>@</email> sign is
also a special character in capability files like
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?remote">/etc/remote</ulink>. Escape it with a backslash:</para>
<para>
<literallayout> pn=\@
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>How can I dial a phone number on the command line?</para></question><answer>
<para>Put what's called a ``<emphasis remap=tt>generic</emphasis>'' entry in your
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?remote">/etc/remote</ulink> file. For example:</para>
<para>
<literallayout> 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:
</literallayout>
</para>
<para>Then you can do something like ``<command>tip -115200 5551234</command>''. If you
prefer <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?cu">cu</ulink> over <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?tip">tip</ulink>, use a
generic cu entry:</para>
<para>
<literallayout> cu115200|Use cu to dial any number at 115200bps:\
:dv=/dev/cuaa1:br#57600:at=hayes:pa=none:du:
</literallayout>
</para>
<para>and type ``<command>cu 5551234 -s 115200</command>''.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Do I have to type in the bps rate every time I do that?</para></question><answer>
<para>Put in an entry for <emphasis remap=tt>tip1200</emphasis> or <emphasis remap=tt>cu1200</emphasis>, but go ahead and
use whatever bps rate is appropriate with the br capability. <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?tip">tip</ulink> thinks a good
default is 1200 bps which is why it looks for a ``<emphasis remap=tt>tip1200</emphasis>'' entry.
You don't have to use 1200 bps, though.</para>
</answer></qandaentry>
<qandaentry><question>
<para>I access a number of hosts through a terminal server.</para></question><answer>
<para>Rather than waiting until you're connected and typing
``<emphasis remap=tt>CONNECT &lt;host&gt;</emphasis>'' each time, use tip's <emphasis remap=tt>cm</emphasis>
capability. For example, these entries in
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?remote">/etc/remote</ulink>:</para>
<para>
<literallayout> 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/cua02:br#38400:at=hayes:du:pa=none:pn=5551234:
</literallayout>
</para>
<para>will let you type ``<emphasis remap=tt>tip pain</emphasis>'' or ``<emphasis remap=tt>tip muffin</emphasis>'' to
connect to the hosts pain or muffin; and ``<emphasis remap=tt>tip deep13</emphasis>'' to
get to the terminal server.</para>
</answer></qandaentry>
<qandaentry><question>
<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 <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?remote">/etc/remote</ulink>
and use <email>\@</email> for the <emphasis remap=tt>pn</emphasis> capability:</para>
<para>
<literallayout> big-university:\
:pn=\@:tc=dialout
dialout:\
:dv=/dev/cuaa3:br#9600:at=courier:du:pa=none:
</literallayout>
</para>
<para>Then, list the phone numbers for the university in
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?phones">/etc/phones</ulink>:</para>
<para>
<literallayout> big-university 5551111
big-university 5551112
big-university 5551113
big-university 5551114
</literallayout>
</para>
<para><ulink URL="http://www.FreeBSD.org/cgi/man.cgi?tip">tip</ulink> will try each one in the listed order, then give up. If
you want to keep retrying, run <emphasis remap=tt>tip</emphasis> in a while loop.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Why do I have to hit CTRL+P twice to send CTRL+P once?</para></question><answer>
<para>CTRL+P is the default ``force'' character, used to tell
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?tip">tip</ulink>
that the next character is literal data. You can set the force
character to any other character with the <emphasis remap=tt>~s</emphasis> escape, which
means ``set a variable.''</para>
<para>Type ``<literal>~sforce=&lt;single-char&gt;</literal>'' followed by a newline.
<emphasis remap=tt>&lt;single-char&gt;</emphasis> is any single character. If you leave
out <emphasis remap=tt>&lt;single-char&gt;</emphasis>, then the force character is the nul
character, which you can get by typing CTRL+2 or CTRL+SPACE. A
pretty good value for <emphasis remap=tt>&lt;single-char&gt;</emphasis> is SHIFT+CTRL+6,
which I've 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>&#36;HOME/.tiprc</filename>
file:</para>
<para>
<literallayout> force=&lt;single-char&gt;
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>Suddenly everything I type is in UPPER CASE??</para></question><answer>
<para>You must've pressed CTRL+A, <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?tip">tip</ulink> ``raise
character,'' specially designed for people with broken caps-lock keys.
Use <emphasis remap=tt>~s</emphasis> as above and set the variable ``raisechar'' 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's a sample .tiprc file perfect for Emacs users who need to
type CTRL+2 and CTRL+A a lot:</para>
<para>
<literallayout> force=^^
raisechar=^^
</literallayout>
</para>
<para>The ^^ is SHIFT+CTRL+6.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How can I do file transfers with <emphasis remap=tt>tip</emphasis>?</para></question><answer>
<para>If you're talking to another UNIX system, you can send and
receive files with <emphasis remap=tt>~p</emphasis> (put) and <emphasis remap=tt>~t</emphasis> (take). These
commands run <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?cat">cat</ulink> and <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?echo">echo</ulink> on the remote system to accept and send files. The syntax
is:</para>
<para>
<literallayout> ~p &lt;local-file&gt; [&lt;remote-file&gt;]
~t &lt;remote-file&gt; [&lt;local-file&gt;]
</literallayout>
</para>
<para>There's no error checking, so you probably should use another
protocol, like zmodem.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How can I run zmodem with <emphasis remap=tt>tip</emphasis>?</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,
<ulink URL="http://www.FreeBSD.org/cgi/ports.cgi?^lrzsz">lrzsz</ulink>
and <ulink URL="http://www.FreeBSD.org/cgi/ports.cgi?^rzsz">rzsz</ulink>).</para>
<para>To receive files, start the sending program on the remote end.
Then, press enter and type ``<emphasis remap=tt>~C rz</emphasis>'' (or ``<emphasis remap=tt>~C lrz</emphasis>'' if
you installed lrzsz) to begin receiving them locally.</para>
<para>To send files, start the receiving program on the remote end.
Then, press enter and type ``<emphasis remap=tt>~C sz &lt;files&gt;</emphasis>'' (or
``<emphasis remap=tt>~C lsz &lt;files&gt;</emphasis>'') to send them to the
remote system.</para>
</answer></qandaentry>
<qandaentry><question>
<para>FreeBSD can't seem to find my serial ports, even when the
settings are correct.</para></question><answer>
<para>Motherboards and cards with Acer UARTs do not probe properly under
the FreeBSD sio probe. Obtain a patch from
<ulink URL="http://www.lemis.com/serial-port-patch.html">www.lemis.com</ulink> to fix your problem.</para>
</answer></qandaentry></qandaset>
</chapter>
<chapter
id="misc">
<title>Miscellaneous Questions</title>
<qandaset><qandaentry><question>
<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 truely 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>
<para> Why use (what are) a.out and ELF executable formats?
</para></question><answer>
<para>To understand why FreeBSD uses the <filename>a.out</filename> format, you must
first know a little about the 3 currently "dominant" executable
formats for UNIX:</para>
<para>
<itemizedlist>
<listitem>
<para><ulink URL="http://www.FreeBSD.org/cgi/man.cgi?a.out(5)">a.out</ulink>
</para>
<para>The oldest and `classic' unix object format. It uses a
short and compact header with a magic number at the beginning
that's often used to characterize the format (see
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?a.out(5)">a.out(5)</ulink> for more details). It contains three loaded
segments: .text, .data, and .bss plus a symbol table and a
string table.</para>
<para></para>
</listitem>
<listitem>
<para><acronym>COFF</acronym>
</para>
<para>The SVR3 object format. The header now comprises a section
table, so you can have more than just .text, .data, and .bss
sections.</para>
</listitem>
<listitem>
<para><acronym>ELF</acronym>
</para>
<para>The successor to <acronym>COFF</acronym>, featuring Multiple sections
and 32-bit or 64-bit possible values. One major drawback:
<acronym>ELF</acronym> was also designed with the assumption that there
would be only one ABI per system architecture. That
assumption is actually quite incorrect, and not even in the
commercial SYSV world (which has at least three ABIs: SVR4,
Solaris, SCO) does it hold true.</para>
<para></para>
<para>FreeBSD tries to work around this problem somewhat by
providing a utility for <emphasis>branding</emphasis> a known <acronym>ELF</acronym>
executable with information about the ABI it's compliant with.
See the man page for
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?brandelf">brandelf</ulink> for more information.</para>
</listitem>
</itemizedlist>
</para>
<para>FreeBSD comes from the "classic" camp and has traditionally used
the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?a.out(5)">a.out</ulink> format, a technology tried and proven through
many generations of BSD releases. Though it has also been possible
for some time to build and run native <acronym>ELF</acronym> binaries (and
kernels) on a FreeBSD system, FreeBSD initially resisted the "push"
to switch to <acronym>ELF</acronym> as the default format. Why? Well,
when the Linux camp made their painful transition to <acronym>ELF</acronym>, it
was not so much to flee the <filename>a.out</filename> executable format
as it was their inflexible jump-table based shared library
mechanism, which made the construction of shared libraries
very difficult for vendors and developers alike. Since the <acronym>ELF</acronym>
tools available offered a solution to the shared library
problem and were generally seen as "the way forward" anyway, the
migration cost was accepted as necessary and the transition
made.</para>
<para>In FreeBSD's case, our shared
library mechanism is based more closely on Sun's
<emphasis remap=tt>SunOS</emphasis>-style shared library mechanism and, as such, is very
easy to use.
However, starting with 3.0, FreeBSD officially supports <acronym>ELF</acronym>
binaries as the default format. Even though the <filename>a.out</filename>
executable format has served us well, the GNU people, who author the
compiler tools we use, have dropped support for the <filename>a.out</filename>
format. This has forced us to maintain a divergent version of
the compler and linker, and has kept us from reaping the benefits
of the latest GNU development efforts. Also the demands of
ISO-C++, notably contstructors and destructors, has also led to
native <acronym>ELF</acronym> support in future FreeBSD releases.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Yes, but why are there so many different
formats?</para></question><answer>
<para>Back in the dim, dark past, there was simple hardware. This
simple hardware supported a simple, small system. a.out was
completely adequate for the job of representing binaries on this
simple system (a PDP-11). As people ported unix from this
simple system, they retained the a.out format because it was
sufficient for the early ports of unix to architectures like the
Motorola 68k, VAXen, etc.</para>
<para>Then some bright hardware engineer decided that if he could
force software to do some sleazy tricks, then he'd be able to
shave a few gates off the design and allow his CPU core to run
faster. While it was made to work with this new kind of
hardware (known these days as RISC), <filename>a.out</filename> was ill-suited
for this hardware, so many formats were developed to get to a
better performance from this hardware than the limited, simple
<filename>a.out</filename> format could offer. Things like <acronym>COFF</acronym>,
<acronym>ECOFF</acronym>, and a few obscure others were invented and their
limitations explored before things seemed to settle on <acronym>ELF</acronym>.</para>
<para>In addition, program sizes were getting huge and disks (and
physical memory) were still relatively small so the concept of a
shared library was born. The VM system also became more
sophisticated. While each one of these advancements was done
using the <filename>a.out</filename> format, its usefulness was stretched more
and more with each new feature. In addition, people wanted to
dynamically load things at run time, or to junk parts of their
program after the init code had run to save in core memory
and/or swap space. Languages became more sophistocated and
people wanted code called before main automatically. Lots of
hacks were done to the <filename>a.out</filename> format to allow all of these
things to happen, and they basically worked for a time. In
time, <filename>a.out</filename> wasn't up to handling all these problems
without an ever increasing overhead in code and complexity.
While <acronym>ELF</acronym> solved many of these problems, it would be
painful to switch from the system that basically worked. So
<acronym>ELF</acronym> had to wait until it was more painful to remain with
<filename>a.out</filename> than it was to migrate to <acronym>ELF</acronym>.</para>
<para>However, as time passed, the build tools that FreeBSD derived
their build tools from (the assembler and loader especially)
evolved in two parallel trees. The FreeBSD tree added shared
libraries and fixed some bugs. The GNU folks that originally
write these programs rewrote them and added simpler support for
building cross compilers, plugging in different formats at will,
etc. Since many people wanted to build cross compilers
targeting FreeBSD, they were out of luck since the older sources
that FreeBSD had for as and ld weren't up to the task. The new
gnu tools chain (binutils) does support cross compiling,
<acronym>ELF</acronym>, shared libraries, C++ extnensions, etc. In addition,
many vendors are releasing <acronym>ELF</acronym> binaries, and it is a good
thing for FreeBSD to run them. And if it is running <acronym>ELF</acronym>
binaries, why bother having <filename>a.out</filename> any more? It is a tired
old horse that has proven useful for a long time, but it is time
to turn him out to pasture for his long, faithful years of
service.</para>
<para><acronym>ELF</acronym> is more expressive than a.out and will allow more
extensibility in the base system. The <acronym>ELF</acronym> tools are better
maintained, and offer cross compilation support, which is
important to many people. <acronym>ELF</acronym> may be a little slower than
a.out, but trying to measure it can be difficult. There are
also numerous details that are different between the two in how
they map pages, handle init code, etc. None of these are very
important, but they are differences. In time support for
<filename>a.out</filename> will be moved out of the GENERIC kernel, and
eventually removed from the kernel once the need to run legacy
<filename>a.out</filename> programs is past.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Why won't chmod change the permissions on symlinks?</para></question><answer>
<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 <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?chmod">chmod</ulink> and
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?symlink">symlink</ulink>
man pages for more info.</para>
<para><acronym>WARNING</acronym> the ``<option>-R</option>'' option does a <acronym>RECURSIVE</acronym>
<emphasis remap=tt>chmod</emphasis>. Be careful about specifying directories or symlinks
to directories to <emphasis remap=tt>chmod</emphasis>. If you want to change the
permissions of a directory referenced by a symlink, use
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?chmod">chmod</ulink>
without any options and follow the symlink with a trailing slash
(``<filename>/</filename>''). For example, if ``<emphasis remap=tt>foo</emphasis>'' is a symlink to
directory ``<emphasis remap=tt>bar</emphasis>'', and you want to change the permissions of
``<emphasis remap=tt>foo</emphasis>'' (actually ``<emphasis remap=tt>bar</emphasis>''), you would do something like:</para>
<para>
<literallayout> chmod 555 foo/
</literallayout>
</para>
<para>With the trailing slash, <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?chmod">chmod</ulink> will
follow the symlink, ``<emphasis remap=tt>foo</emphasis>'', to change the permissions of the
directory, ``<emphasis remap=tt>bar</emphasis>''.</para>
</answer></qandaentry>
<qandaentry><question>
<para> Why are login names <emphasis remap=bf>still</emphasis> restricted to 8 characters?
</para></question><answer>
<para>You'd think it'd be easy enough to change <symbol>UT_NAMESIZE</symbol> and rebuild
the whole world, and everything would just work. Unfortunately there
are often scads of applications and utilities (including system tools)
that have hard-coded small numbers (not always "8" or "9", but oddball
ones like "15" and "20") in structures and buffers. Not only will
this get you log files which are trashed (due to variable-length
records getting written when fixed records were expected), but it can
break Sun's NIS clients and potentially cause other problems in
interacting with other UNIX systems.</para>
<para>In FreeBSD 3.0 and later, the maximum name length has been
increased to 16 characters and those various utilities with
hard-coded name sizes have been found and fixed. The fact that this
touched so many areas of the system is why, in fact, the change was
not made until 3.0.</para>
<para>If you're absolutely confident in your ability to find and fix
these sorts of problems for yourself when and if they pop up, you
can increase the login name length in earlier releases by editing
/usr/include/utmp.h and changing UT_NAMESIZE accordingly. You must
also update MAXLOGNAME in /usr/include/sys/param.h to match
the UT_NAMESIZE change. Finally, if you build from sources, don't
forget that /usr/include is updated each time! Change the appropriate
files in /usr/src/.. instead.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Can I run DOS binaries under FreeBSD?</para></question><answer>
<para>Yes, starting with version 3.0 you can using BSDI's <emphasis remap=tt>rundos</emphasis>
DOS emulation which has been integrated and enhanced.
Send mail to <ulink URL="mailto:freebsd-emulation@FreeBSD.org">The FreeBSD emulation discussion list</ulink> if you're interested in
joining this ongoing effort!</para>
<para>For pre-3.0 systems, there is a neat utility called
<ulink URL="http://www.FreeBSD.org/cgi/ports.cgi?^pcemu">pcemu</ulink>
in the ports collection which emulates an 8088 and enough BIOS services
to run DOS text mode applications. It requires the X Window
System (provided as XFree86).</para>
</answer></qandaentry>
<qandaentry><question>
<para> What is ``<emphasis remap=tt>sup</emphasis>'', 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="../handbook/synching.html#CVSUP">Handbook entry on CVSup</ulink></para>
</answer></qandaentry>
<qandaentry><question>
<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 particular variances in temperature
that I can remember. 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. I think most of the volunteers are at Apple
now, working on their new ``scratch and sniff'' GUI. It's a
funny old business we're 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 (automatic power management) configured, then FreeBSD
can also put the CPU into a low power mode.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Who's scratching in my memory banks??</para></question><answer>
<para>Q. Is there anything "odd" 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'll see frequent references to ``daemons'' in the BSD
documentation, and what most people don't 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 don't 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 don't 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.
Given a choice, I think I'd prefer to get used to the scratchy
noises, myself!</para>
</answer></qandaentry>
<qandaentry><question>
<para>What does 'MFC' mean?</para></question><answer>
<para>MFC is an acronym for 'Merged From -CURRENT.' It's used in the CVS
logs to denote when a change was migrated from the CURRENT to the STABLE
branches.</para>
</answer></qandaentry>
<qandaentry><question>
<para>What does 'BSD' mean?</para></question><answer>
<para>It stands for something in a secret language that only
members can know. It doesn't translate literally but its ok to
tell you that BSD's translation is something between, 'Formula-1
Racing Team', 'Penguins are tasty snacks', and 'We have a better
sense of humor than Linux.' :-)</para>
<para>Seriously, BSD is an acronym for 'Berkeley Software
Distribution', which is the name the Berkeley CSRG (Computer
Systems Research Group) chose for their Unix distribution way
back when.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How many FreeBSD hackers does it take to change a lightbulb?</para></question><answer>
<para>One thousand, one hundred and seventy-two:</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 "it's dark";</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 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 "unsubscribe", "How do I unsubscribe?", or
"Please remove me from the list", 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 EGCS;</para>
<para>One to complain that the new lightbulb lacks fairings;</para>
<para>Nine (including the PR originators) to ask "what is MFC?";</para>
<para>Fifty-seven to complain about the lights being out two weeks
after the bulb has been changed.</para>
<para><emphasis><ulink URL="mailto:nik@FreeBSD.org">Nik Clayton</ulink>
adds:</emphasis></para>
<para><emphasis>I was laughing quite hard at this.</emphasis></para>
<para><emphasis>And then I thought, "Hang on, shouldn't there be '1 to
document it.' in that list somewhere?"</emphasis></para>
<para><emphasis>And then I was enlightened :-)</emphasis></para>
</answer></qandaentry></qandaset>
</chapter>
<chapter
id="hackers">
<title>For serious FreeBSD hackers only</title>
<qandaset><qandaentry><question>
<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>:</para>
<para>
<itemizedlist>
<listitem>
<para><symbol>RELENG_2_2</symbol> AKA <emphasis remap=bf>2.2-stable</emphasis> AKA <emphasis remap=bf>"2.2 branch"</emphasis></para>
</listitem>
<listitem>
<para><symbol>RELENG_3</symbol> AKA <emphasis remap=bf>3.x-stable</emphasis> AKA <emphasis remap=bf>"3.0 branch"</emphasis></para>
</listitem>
<listitem>
<para><acronym>HEAD</acronym> AKA <option>-current</option> AKA <emphasis remap=bf>4.0-current</emphasis></para>
</listitem>
</itemizedlist>
</para>
<para><acronym>HEAD</acronym> is not an actual branch tag, like the other two, it's
simply a symbolic constant for
<emphasis>"the current, non-branched development stream"</emphasis> which we simply
refer to as <option>-current</option>.</para>
<para>Right now, <option>-current</option> is the 4.0 development stream and the
<emphasis remap=bf>3.0-stable</emphasis> branch, <symbol>RELENG_3</symbol>, forked off from
<option>-current</option> in Jan 1999.</para>
<para>The <emphasis remap=bf>2.2-stable</emphasis> branch, <symbol>RELENG_2_2</symbol>, departed -current in
November 1996.</para>
<para>The <emphasis remap=bf>2.1-stable</emphasis> branch, <symbol>RELENG_2_1_0</symbol>, departed -current in
September of 1994. This branch has been fully retired.</para>
</answer></qandaentry>
<qandaentry><question
id="custrel">
<para> How do I make my own custom release?
</para></question><answer>
<para>To make a release you need to do three things: First, you need to
be running a kernel with the <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?vn">vn</ulink> driver configured
in. Add this to your kernel config file and build a new kernel:</para>
<para>
<literallayout> pseudo-device vn #Vnode driver (turns a file into a device)
</literallayout>
</para>
<para>Second, you have to have the whole CVS repository at hand.
To get this you can use <ulink URL="../handbook/synching.html#CVSUP">CVSUP</ulink>
but in your supfile set the release name to cvs and remove any tag or
date fields:</para>
<para>
<literallayout> *default prefix=/home/ncvs
*default base=/a
*default host=cvsup.FreeBSD.org
*default release=cvs
*default delete compress use-rel-suffix
## Main Source Tree
src-all
src-eBones
src-secure
# Other stuff
ports-all
www
doc-all
</literallayout>
</para>
<para>Then run <command>cvsup -g supfile</command> to suck all the good bits onto your
box...</para>
<para>Finally, you need a chunk of empty space to build into. Let's
say it's in <filename>/some/big/filesystem</filename>, and from the example
above you've got the CVS repository in <filename>/home/ncvs</filename>:</para>
<para>
<literallayout> setenv CVSROOT /home/ncvs # or export CVSROOT=/home/ncvs
cd /usr/src/release
make release BUILDNAME=3.0-MY-SNAP CHROOTDIR=/some/big/filesystem/release
</literallayout>
</para>
<para>An entire release will be built in
<filename>/some/big/filesystem/release</filename> and you will have a full FTP-type
installation in <filename>/some/big/filesystem/release/R/ftp</filename> when you're
done. If you want to build your SNAP along some other branch than
-current, you can also add <literal>RELEASETAG=SOMETAG</literal> to
the make release command line above, e.g. <literal>RELEASETAG=RELENG_2_2</literal>
would build an up-to-the- minute 2.2-STABLE snapshot.</para>
</answer></qandaentry>
<qandaentry><question>
<para>How do I create customized installation disks?</para></question><answer>
<para>The entire process of creating installation disks and source and
binary archives is automated by various targets in
<filename>/usr/src/release/Makefile</filename>. The information there should
be enough to get you started. However, it should be said that this
involves doing a ``make world'' and will therefore take up a lot of
time and disk space.</para>
</answer></qandaentry>
<qandaentry><question>
<para>``make world'' clobbers my existing installed binaries.</para></question><answer>
<para>Yes, this is the general idea; as its name might suggest,
``make world'' 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 <acronym>DESTDIR</acronym> is defined while running
``<emphasis remap=tt>make world</emphasis>'' or ``<emphasis remap=tt>make install</emphasis>'', the newly-created
binaries will be deposited in a directory tree identical to the
installed one, rooted at <emphasis remap=tt>&#36;{DESTDIR}</emphasis>.
Some random combination of shared libraries modifications and
program rebuilds can cause this to fail in ``<emphasis remap=tt>make world</emphasis>'',
however.</para>
</answer></qandaentry>
<qandaentry><question>
<para> When my system boots, it says ``(bus speed defaulted)''.
</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 doesn't, 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 remap=tt>without</emphasis> downloading the whole source tree
by using the <ulink URL="../handbook/synching.html#CTM">CTM facility.</ulink></para>
</answer></qandaentry>
<qandaentry><question>
<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 split that
allows them to split files on arbitrary byte boundaries.</para>
<para>Here is an example from <filename>/usr/src/Makefile</filename>.</para>
<para>
<literallayout> bin-tarball:
(cd ${DISTDIR}; \
tar cf - . \
gzip --no-name -9 -c | \
split -b 240640 - \
${RELEASEDIR}/tarballs/bindist/bin_tgz.)
</literallayout>
</para>
</answer></qandaentry>
<qandaentry><question>
<para>I've written a kernel extension, who do I send it to?</para></question><answer>
<para>Please take a look at <ulink URL="../handbook/contrib.html">The Handbook entry on how to submit code.</ulink></para>
<para>And thanks for the thought!</para>
</answer></qandaentry>
<qandaentry><question>
<para>How are Plug N Play ISA cards detected and initialized?</para></question><answer>
<para>By: <ulink URL="mailto:uhclem@nemesis.lonestar.org">Frank Durda IV</ulink></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, he 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
``yes'' 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
``off-line''. It then looks to see if any boards are still
responding to the query. If the answer was ``<emphasis remap=tt>0</emphasis>'', then
there are no boards with IDs above X. Now probe asks if there
are any boards below ``X''. 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 don't 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 can't 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 ``tough''. 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>
<para>Does FreeBSD support architectures other than the x86?</para></question><answer>
<para>Several groups of people have expressed interest in working on
multi-architecture ports for FreeBSD and the FreeBSD/AXP (ALPHA)
port is one such effort which has been quite successful, now
available in 3.0 SNAPshot release form at <ulink URL="ftp://ftp.FreeBSD.org/pub/FreeBSD/alpha/">ftp://ftp.FreeBSD.org/pub/FreeBSD/alpha</ulink>. The ALPHA
port currently runs on a growing number of ALPHA machine
types, among them the AlphaStation, AXPpci, PC164, Miata and Multia
models. This port is not yet considered a full release and won't be
until a full compliment of system installation tools and a distribution
on CDROM installation media is available, including a reasonable
number of working ports and packages.
FreeBSD/AXP should be considered BETA quality software at this
time. For status information, please join the
<email>&lt;freebsd-alpha@FreeBSD.org&gt;</email><xref linkend="mailing" remap="mailing list">.</para>
<para>Interest has also been expressed in a port of FreeBSD to
the SPARC architecture, join the <email>&lt;freebsd-sparc@FreeBSD.org&gt;</email><xref linkend="mailing" remap="mailing list"> if you are interested
in joining that project. For general discussion on new architectures,
join the <email>&lt;freebsd-platforms@FreeBSD.org&gt;</email>
<xref linkend="mailing" remap="mailing list">.</para>
</answer></qandaentry>
<qandaentry><question>
<para>I need a major number for a device driver I've written.</para></question><answer>
<para>This 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
<emphasis remap=tt>files.i386</emphasis>, a sample configuration file entry, and the
appropriate <ulink URL="http://www.FreeBSD.org/cgi/man.cgi?MAKEDEV">MAKEDEV</ulink> 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'd
appreciate hearing about your driver on
<email>&lt;freebsd-hackers@FreeBSD.org&gt;</email>.</para>
</answer></qandaentry>
<qandaentry><question>
<para>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 senario 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>
<para>Making the most of a kernel panic</para></question><answer>
<para>
<emphasis>[This section was extracted from a mail written by <ulink URL="mailto:wpaul@FreeBSD.org">Bill Paul</ulink> on the
freebsd-current <xref linkend="mailing" remap="mailing list"> by <ulink URL="mailto:des@FreeBSD.org">Dag-Erling Co&iuml;dan Sm&oslash;rgrav</ulink>, who fixed a few typos and added the bracketed
comments]</emphasis></para>
<para>
<literallayout>From: Bill Paul &lt;wpaul@skynet.ctr.columbia.edu&gt;
Subject: Re: the fs fun never stops
To: ben@rosengart.com
Date: Sun, 20 Sep 1998 15:22:50 -0400 (EDT)
Cc: current@FreeBSD.org
</literallayout>
</para>
<para><emphasis>[&lt;ben@rosengart.com&gt; posted the following panic
message]</emphasis>
<literallayout>&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
</literallayout>
</para>
<para> [When] you see a message like this, it's not enough to just
reproduce it and send it in. The instruction pointer value that
I highlighted up there is important; unfortunately, it's also
configuration dependent. In other words, the value varies
depending on the exact kernel image that you're using. If you're
using a GENERIC kernel image from one of the snapshots, then
it's possible for somebody else to track down the offending
function, but if you're running a custom kernel then only
<emphasis>you</emphasis> can tell us where the fault occured.</para>
<para> What you should do is this:</para>
<para>
<itemizedlist>
<listitem>
<para>Write down the instruction pointer value. Note that the
<literal>0x8:</literal> part at the begining is not significant in this case:
it's the <literal>0xf0xxxxxx</literal> part that we want.</para>
</listitem>
<listitem>
<para>When the system reboots, do the following:
<literallayout>% nm /kernel.that.caused.the.panic | grep f0xxxxxx
</literallayout>
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 don't
get an exact match, omit the last digit from the instruction
pointer value and try again, i.e.:
<literallayout>% nm /kernel.that.caused.the.panic | grep f0xxxxx
</literallayout>
If that doesn't 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's better than nothing.</para>
</listitem>
</itemizedlist>
</para>
<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 <command>gdb(1)</command> to to a stack
trace on the crash dump. Of course, this depends on <command>gdb(1)</command>
in -current working correctly, which I can't guarantee (I recall
somebody saying that the new ELF-ized <command>gdb(1)</command> didn't handle
kernel crash dumps correctly: somebody should check this before
3.0 goes out of beta or there'll be a lot of red faces after the
CDs ship).</para>
<para>In any case, the method I normally use is this:</para>
<para>
<itemizedlist>
<listitem>
<para>Set up a kernel config file, optionally adding 'options DDB' if you
think you need the kernel debugger for something. (I use this mainly
for setting beakpoints if I suspect an infinite loop condition of
some kind.)</para>
</listitem>
<listitem>
<para>Use <command>config -g KERNELCONFIG</command> to set up the build directory.</para>
</listitem>
<listitem>
<para><command>cd /sys/compile/KERNELCONFIG; make</command></para>
</listitem>
<listitem>
<para>Wait for kernel to finish compiling.</para>
</listitem>
<listitem>
<para><emphasis remap=tt>cp kernel kernel.debug</emphasis></para>
</listitem>
<listitem>
<para><command>strip -d kernel</command></para>
</listitem>
<listitem>
<para><emphasis remap=tt>mv </emphasis>kernel /kernel.orig/</para>
</listitem>
<listitem>
<para><command>cp kernel /</command></para>
</listitem>
<listitem>
<para>reboot</para>
</listitem>
</itemizedlist>
</para>
<para> <emphasis>[Note: Now that FreeBSD 3.x kernels are Elf by default,
you should use <command>strip -g</command> instead of <command>strip -d</command>. If for some
reason your kernel is still a.out, use <command>strip -aout -d</command>.]</emphasis></para>
<para> Note that YOU DO <acronym>NOT</acronym> WANT TO ACTUALLY BOOT THE KERNEL
WITH ALL THE DEBUG SYMBOLS IN IT. A kernel compiled with <option>-g</option>
can easily be close to 10MB in size. You don't have to actually
boot this massive image: you only need it later for <command>gdb(1)</command>
(<command>gdb(1)</command> wants the symbol table). Instead, you want to keep
a copy of the full image and create a second image with the
debug symbols stripped out using <command>strip -d</command>. It is this
second stripped image that you want to boot.</para>
<para> To make sure you capture a crash dump, you need edit
<filename>/etc/rc.conf</filename> and set <emphasis remap=tt>dumpdev</emphasis> to point to your swap
partition. This will cause the <command>rc(8)</command> scripts to use the
<command>dumpon(8)</command> command to enable crash dumps. You can also run
<command>dumpon(8)</command> manually. After a panic, the crash dump can be
recovered using <command>savecore(8)</command>; if <emphasis remap=tt>dumpdev</emphasis> is set in
<filename>/etc/rc.conf</filename>, the <command>rc(8)</command> scripts will run
<command>savecore(8)</command> automatically and put the crash dump in
<filename>/var/crash</filename>.</para>
<para> NOTE: 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's enough space in <filename>/var/crash</filename> to hold the dump.
Alternatively, you run <command>savecore(8)</command> manually and have it
recover the crash dump to another directory where you have more
room. It's 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>
<para> Once you have recovered the crash dump, you can get a stack
trace with <command>gdb(1)</command> as follows:</para>
<para>
<literallayout>% gdb -k /sys/compile/KERNELCONFIG/kernel.debug /var/crash/vmcore.0
(gdb) where
</literallayout>
</para>
<para> Note that there may be several screens worth of information;
ideally you should use <command>script(1)</command> 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
occured. 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 <command>gdb(1)</command> 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're really insane and have a second computer, you
can also configure <command>gdb(1)</command> to do remote debugging such that
you can use <command>gdb(1)</command> 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 haven't played with this yet as I don't
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>
<para>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 <emphasis remap=tt>dlopen(NULL, flags)</emphasis> 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
<ulink URL="http://www.FreeBSD.org/cgi/man.cgi?ld">ELF linker</ulink>.</para>
</answer></qandaentry>
<qandaentry><question>
<para>Increasing or reducing 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 doesn't bump its head against the
ceiling.</para>
<para>The first goal is achieved by increasing the value of
<acronym>NKPDE</acronym> in <filename>src/sys/i386/include/pmap.h</filename>. Here's what
it looks like for a 1 GB address space:</para>
<para>
<literallayout>#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
</literallayout>
</para>
<para>To find the correct value of <acronym>NKPDE</acronym>, 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>
<para>
<literallayout>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) }
</literallayout>
</para>
<para>Then reconfig and rebuild your kernel. You will probably have
problems with <command>ps(1)</command>, <command>top(1)</command> and the like; <emphasis remap=tt>make
world</emphasis> should take care of it (or a manual rebuild of
<emphasis remap=tt>libkvm</emphasis>, <emphasis remap=tt>ps</emphasis> and <emphasis remap=tt>top</emphasis> 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>[<ulink URL="mailto:dg@FreeBSD.org">David Greenman</ulink>
adds: <emphasis> I think the kernel address space needs to be a power
of two, but I'm 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>
<para>
<literallayout> If you see a problem with this FAQ, or wish to submit an entry,
please mail us at &lt;FAQ@FreeBSD.org&gt;. We appreciate your
feedback, and cannot make this a better FAQ without your help!
FreeBSD Core Team
</literallayout>
</para>
<para>
<variablelist>
<varlistentry><term>Jordan Hubbard</term>
<listitem>
<para>Occasional fits of FAQ-reshuffling and updating.</para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>Doug White</term>
<listitem>
<para>Services above and beyond the call of duty on freebsd-questions</para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>Joerg Wunsch</term>
<listitem>
<para>Services above and beyond the call of duty on Usenet</para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>Garrett Wollman</term>
<listitem>
<para>Networking and formatting</para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>Jim Lowe</term>
<listitem>
<para>Multicast information</para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>Peter da Silva</term>
<listitem>
<para>FreeBSD FAQ typing machine slavey</para>
<para></para>
</listitem>
</varlistentry>
<varlistentry><term>The FreeBSD Team</term>
<listitem>
<para>Kvetching, moaning, submitting data</para>
</listitem>
</varlistentry>
</variablelist>
</para>
<para>And to any others we've forgotten, apologies and heartfelt thanks!</para>
</chapter>
</book>
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