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<preface id="book-preface">
<title>Preface</title>
<bridgehead id="preface-audience" renderas="sect1">Intended
Audience</bridgehead>
<para>The &os; newcomer will find that the first section of this
book guides the user through the &os; installation process and
gently introduces the concepts and conventions that underpin
&unix;. Working through this section requires little more than
the desire to explore, and the ability to take on board new
concepts as they are introduced.</para>
<para>Once you have traveled this far, the second, far larger,
section of the Handbook is a comprehensive reference to all manner
of topics of interest to &os; system administrators. Some of
these chapters may recommend that you do some prior reading, and
this is noted in the synopsis at the beginning of each
chapter.</para>
<para>For a list of additional sources of information, please see
<xref linkend="bibliography"/>.</para>
<bridgehead id="preface-changes-from3" renderas="sect1">Changes
from the Third Edition</bridgehead>
<para>The current online version of the Handbook represents the
cumulative effort of many hundreds of contributors over the past
10 years. The following are some of the significant changes since
the two volume third edition was published in 2004:</para>
<itemizedlist>
<listitem>
<para><xref linkend="dtrace"/>, &dtrace;, has been added with
information about the powerful &dtrace; performance analysis
tool.</para>
</listitem>
<listitem>
<para><xref linkend="filesystems"/>, File Systems Support, has
been added with information about non-native file systems in
&os;, such as ZFS from &sun;.</para>
</listitem>
<listitem>
<para><xref linkend="audit"/>, Security Event Auditing, has
been added to cover the new auditing capabilities in &os;
and explain its use.</para>
</listitem>
<listitem>
<para><xref linkend="virtualization"/>, Virtualization, has
been added with information about installing &os; on
virtualization software.</para>
</listitem>
<listitem>
<para><xref linkend="bsdinstall"/>, Installing
&os; 9.<replaceable>x</replaceable> and Later, has been
added to cover installation of &os; using the new
installation utility,
<application>bsdinstall</application>.</para>
</listitem>
</itemizedlist>
<bridgehead id="preface-changes-from2" renderas="sect1">Changes
from the Second Edition (2004)</bridgehead>
<para>The third edition was the culmination of over two years of
work by the dedicated members of the &os; Documentation
Project. The printed edition grew to such a size that it was
necessary to publish as two separate volumes. The following are
the major changes in this new edition:</para>
<itemizedlist>
<listitem>
<para><xref linkend="config-tuning"/>, Configuration and
Tuning, has been expanded with new information about the
ACPI power and resource management, the
<command>cron</command> system utility, and more kernel
tuning options.</para>
</listitem>
<listitem>
<para><xref linkend="security"/>, Security, has been expanded
with new information about virtual private networks (VPNs),
file system access control lists (ACLs), and security
advisories.</para>
</listitem>
<listitem>
<para><xref linkend="mac"/>, Mandatory Access Control (MAC),
is a new chapter with this edition. It explains what MAC is
and how this mechanism can be used to secure a &os;
system.</para>
</listitem>
<listitem>
<para><xref linkend="disks"/>, Storage, has been expanded with
new information about USB storage devices, file system
snapshots, file system quotas, file and network backed
filesystems, and encrypted disk partitions.</para>
</listitem>
<listitem>
<para>A troubleshooting section has been added to <xref
linkend="ppp-and-slip"/>, PPP and SLIP.</para>
</listitem>
<listitem>
<para><xref linkend="mail"/>, Electronic Mail, has been
expanded with new information about using alternative
transport agents, SMTP authentication, UUCP,
<application>fetchmail</application>,
<application>procmail</application>, and other advanced
topics.</para>
</listitem>
<listitem>
<para><xref linkend="network-servers"/>, Network Servers, is
all new with this edition. This chapter includes
information about setting up the <application>Apache HTTP
Server</application>, <application>ftpd</application>,
and setting up a server for µsoft; &windows; clients
with <application>Samba</application>. Some sections from
<xref linkend="advanced-networking"/>, Advanced Networking,
were moved here to improve the presentation.</para>
</listitem>
<listitem>
<para><xref linkend="advanced-networking"/>, Advanced
Networking, has been expanded with new information about
using &bluetooth; devices with &os;, setting up wireless
networks, and Asynchronous Transfer Mode (ATM)
networking.</para>
</listitem>
<listitem>
<para>A glossary has been added to provide a central location
for the definitions of technical terms used throughout the
book.</para>
</listitem>
<listitem>
<para>A number of aesthetic improvements have been made to the
tables and figures throughout the book.</para>
</listitem>
</itemizedlist>
<bridgehead id="preface-changes" renderas="sect1">Changes from the
First Edition (2001)</bridgehead>
<para>The second edition was the culmination of over two years of
work by the dedicated members of the &os; Documentation
Project. The following were the major changes in this
edition:</para>
<!-- Talk a little about justification and other stylesheet changes? -->
<itemizedlist>
<listitem>
<para>A complete Index has been added.</para>
</listitem>
<listitem>
<para>All ASCII figures have been replaced by graphical
diagrams.</para>
</listitem>
<listitem>
<para>A standard synopsis has been added to each chapter to
give a quick summary of what information the chapter
contains, and what the reader is expected to know.</para>
</listitem>
<listitem>
<para>The content has been logically reorganized into three
parts: <quote>Getting Started</quote>, <quote>System
Administration</quote>, and
<quote>Appendices</quote>.</para>
</listitem>
<listitem>
<para><xref linkend="install"/> (<quote>Installing
&os;</quote>) was completely rewritten with many
screenshots to make it much easier for new users to grasp
the text.</para>
</listitem>
<listitem>
<para><xref linkend="basics"/> (<quote>&unix; Basics</quote>)
has been expanded to contain additional information about
processes, daemons, and signals.</para>
</listitem>
<listitem>
<para><xref linkend="ports"/> (<quote>Installing
Applications</quote>) has been expanded to contain
additional information about binary package
management.</para>
</listitem>
<listitem>
<para><xref linkend="x11"/> (<quote>The X Window
System</quote>) has been completely rewritten with an
emphasis on using modern desktop technologies such as
<application>KDE</application> and
<application>GNOME</application> on &xfree86; 4.X.</para>
</listitem>
<listitem>
<para><xref linkend="boot"/> (<quote>The &os; Booting
Process</quote>) has been expanded.</para>
</listitem>
<listitem>
<para><xref linkend="disks"/> (<quote>Storage</quote>) has
been written from what used to be two separate chapters on
<quote>Disks</quote> and <quote>Backups</quote>. We feel
that the topics are easier to comprehend when presented as
a single chapter. A section on RAID (both hardware and
software) has also been added.</para>
</listitem>
<listitem>
<para><xref linkend="serialcomms"/> (<quote>Serial
Communications</quote>) has been completely
reorganized and updated for &os; 4.X/5.X.</para>
</listitem>
<listitem>
<para><xref linkend="ppp-and-slip"/> (<quote>PPP and
SLIP</quote>) has been substantially updated.</para>
</listitem>
<listitem>
<para>Many new sections have been added to
<xref linkend="advanced-networking"/>
(<quote>Advanced Networking</quote>).</para>
</listitem>
<listitem>
<para><xref linkend="mail"/> (<quote>Electronic Mail</quote>)
has been expanded to include more information about
configuring <application>sendmail</application>.</para>
</listitem>
<listitem>
<para><xref linkend="linuxemu"/> (<quote>&linux;
Compatibility</quote>) has been expanded to include
information about installing
<application>&oracle;</application> and
<application>&sap.r3;</application>.</para>
</listitem>
<listitem>
<para>The following new topics are covered in this second
edition:</para>
<itemizedlist>
<listitem>
<para>Configuration and Tuning (<xref
linkend="config-tuning"/>).</para>
</listitem>
<listitem>
<para>Multimedia (<xref linkend="multimedia"/>)</para>
</listitem>
</itemizedlist>
</listitem>
</itemizedlist>
<bridgehead id="preface-overview" renderas="sect1">Organization of
This Book</bridgehead>
<para>This book is split into five logically distinct sections.
The first section, <emphasis>Getting Started</emphasis>, covers
the installation and basic usage of &os;. It is expected that
the reader will follow these chapters in sequence, possibly
skipping chapters covering familiar topics. The second section,
<emphasis>Common Tasks</emphasis>, covers some frequently used
features of &os;. This section, and all subsequent sections,
can be read out of order. Each chapter begins with a succinct
synopsis that
describes what the chapter covers and what the reader is expected
to already know. This is meant to allow the casual reader to skip
around to find chapters of interest. The third section,
<emphasis>System Administration</emphasis>, covers administration
topics. The fourth section, <emphasis>Network
Communication</emphasis>, covers networking and server topics.
The fifth section contains
appendices of reference information.</para>
<variablelist>
<!-- Part I - Introduction -->
<varlistentry>
<term><emphasis><xref linkend="introduction"/>,
Introduction</emphasis></term>
<listitem>
<para>Introduces &os; to a new user. It describes the
history of the &os; Project, its goals and development
model.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="install"/>, Installation of
&os; 8.<replaceable>x</replaceable> and
Earlier</emphasis></term>
<listitem>
<para>Walks a user through the entire installation process of
&os; 8.<replaceable>x</replaceable> and earlier using
<application>sysinstall</application>. Some advanced
installation topics, such as installing through a serial
console, are also covered.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="bsdinstall"/>, Installation of
&os; 9.<replaceable>x</replaceable> and
Later</emphasis></term>
<listitem>
<para>Walks a user through the entire installation process of
&os; 9.<replaceable>x</replaceable> and later using
<application>bsdinstall</application>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="basics"/>, &unix;
Basics</emphasis></term>
<listitem>
<para>Covers the basic commands and functionality of the
&os; operating system. If you are familiar with &linux;
or another flavor of &unix; then you can probably skip this
chapter.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="ports"/>, Installing
Applications</emphasis></term>
<listitem>
<para>Covers the installation of third-party software with
both &os;'s innovative <quote>Ports Collection</quote> and
standard binary packages.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="x11"/>, The X Window
System</emphasis></term>
<listitem>
<para>Describes the X Window System in general and using
X11 on &os; in particular. Also describes common
desktop environments such as <application>KDE</application>
and <application>GNOME</application>.</para>
</listitem>
</varlistentry>
<!-- Part II Common Tasks -->
<varlistentry>
<term><emphasis><xref linkend="desktop"/>, Desktop
Applications</emphasis></term>
<listitem>
<para>Lists some common desktop applications, such as web
browsers and productivity suites, and describes how to
install them on &os;.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="multimedia"/>,
Multimedia</emphasis></term>
<listitem>
<para>Shows how to set up sound and video playback support
for your system. Also describes some sample audio and video
applications.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="kernelconfig"/>, Configuring
the &os; Kernel</emphasis></term>
<listitem>
<para>Explains why you might need to configure a new kernel
and provides detailed instructions for configuring,
building, and installing a custom kernel.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="printing"/>,
Printing</emphasis></term>
<listitem>
<para>Describes managing printers on &os;, including
information about banner pages, printer accounting, and
initial setup.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="linuxemu"/>, &linux; Binary
Compatibility</emphasis></term>
<listitem>
<para>Describes the &linux; compatibility features of &os;.
Also provides detailed installation instructions for many
popular &linux; applications such as
<application>&oracle;</application> and
<application>&mathematica;</application>.</para>
</listitem>
</varlistentry>
<!-- Part III - System Administration -->
<varlistentry>
<term><emphasis><xref linkend="config-tuning"/>, Configuration
and Tuning</emphasis></term>
<listitem>
<para>Describes the parameters available for system
administrators to tune a &os; system for optimum
performance. Also describes the various configuration files
used in &os; and where to find them.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="boot"/>, Booting
Process</emphasis></term>
<listitem>
<para>Describes the &os; boot process and explains
how to control this process with configuration
options.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="users"/>, Users and Basic Account
Management</emphasis></term>
<listitem>
<para>Describes the creation and manipulation of user
accounts. Also discusses resource limitations that can be
set on users and other account management tasks.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="security"/>,
Security</emphasis></term>
<listitem>
<para>Describes many different tools available to help keep
your &os; system secure, including Kerberos, IPsec and
OpenSSH.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="jails"/>, Jails</emphasis></term>
<listitem>
<para>Describes the jails framework, and the improvements of
jails over the traditional chroot support of &os;.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="mac"/>, Mandatory Access
Control</emphasis></term>
<listitem>
<para>Explains what Mandatory Access Control (MAC) is and
how this mechanism can be used to secure a &os;
system.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="audit"/>, Security Event
Auditing</emphasis></term>
<listitem>
<para>Describes what &os; Event Auditing is, how it can be
installed, configured, and how audit trails can be inspected
or monitored.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="disks"/>,
Storage</emphasis></term>
<listitem>
<para>Describes how to manage storage media and filesystems
with &os;. This includes physical disks, RAID arrays,
optical and tape media, memory-backed disks, and network
filesystems.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="geom-synopsis"/>,
GEOM</emphasis></term>
<listitem>
<para>Describes what the GEOM framework in &os; is and how
to configure various supported RAID levels.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="filesystems"/>, File Systems
Support</emphasis></term>
<listitem>
<para>Examines support of non-native file systems in &os;,
like the Z File System from &sun;.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="virtualization"/>,
Virtualization</emphasis></term>
<listitem>
<para>Describes what virtualization systems offer, and how
they can be used with &os;.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="l10n"/>,
Localization</emphasis></term>
<listitem>
<para>Describes how to use &os; in languages other than
English. Covers both system and application level
localization.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="updating-upgrading"/>, Updating
and Upgrading &os;</emphasis></term>
<listitem>
<para>Explains the differences between &os;-STABLE,
&os;-CURRENT, and &os; releases. Describes which users
would benefit from tracking a development system and
outlines that process. Covers the methods users may take
to update their system to the latest security
release.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="dtrace"/>,
&dtrace;</emphasis></term>
<listitem>
<para>Describes how to configure and use the &dtrace; tool
from &sun; in &os;. Dynamic tracing can help locate
performance issues, by performing real time system
analysis.</para>
</listitem>
</varlistentry>
<!-- Part IV - Network Communications -->
<varlistentry>
<term><emphasis><xref linkend="serialcomms"/>, Serial
Communications</emphasis></term>
<listitem>
<para>Explains how to connect terminals and modems to your
&os; system for both dial in and dial out
connections.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="ppp-and-slip"/>, PPP and
SLIP</emphasis></term>
<listitem>
<para>Describes how to use PPP, SLIP, or PPP over Ethernet to
connect to remote systems with &os;.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="mail"/>, Electronic
Mail</emphasis></term>
<listitem>
<para>Explains the different components of an email server
and dives into simple configuration topics for the most
popular mail server software:
<application>sendmail</application>.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="network-servers"/>, Network
Servers</emphasis></term>
<listitem>
<para>Provides detailed instructions and example configuration
files to set up your &os; machine as a network filesystem
server, domain name server, network information system
server, or time synchronization server.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="firewalls"/>,
Firewalls</emphasis></term>
<listitem>
<para>Explains the philosophy behind software-based firewalls
and provides detailed information about the configuration
of the different firewalls available for &os;.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="advanced-networking"/>, Advanced
Networking</emphasis></term>
<listitem>
<para>Describes many networking topics, including sharing an
Internet connection with other computers on your LAN,
advanced routing topics, wireless networking, &bluetooth;,
ATM, IPv6, and much more.</para>
</listitem>
</varlistentry>
<!-- Part V - Appendices -->
<varlistentry>
<term><emphasis><xref linkend="mirrors"/>, Obtaining &os;
</emphasis></term>
<listitem>
<para>Lists different sources for obtaining &os; media on
CDROM or DVD as well as different sites on the Internet
that allow you to download and install &os;.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="bibliography"/>,
Bibliography</emphasis></term>
<listitem>
<para>This book touches on many different subjects that may
leave you hungry for a more detailed explanation. The
bibliography lists many excellent books that are referenced
in the text.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="eresources"/>, Resources on the
Internet</emphasis></term>
<listitem>
<para>Describes the many forums available for &os; users to
post questions and engage in technical conversations about
&os;.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><emphasis><xref linkend="pgpkeys"/>, PGP
Keys</emphasis></term>
<listitem>
<para>Lists the PGP fingerprints of several &os;
Developers.</para>
</listitem>
</varlistentry>
</variablelist>
<bridgehead id="preface-conv" renderas="sect1">Conventions used
in this book</bridgehead>
<para>To provide a consistent and easy to read text, several
conventions are followed throughout the book.</para>
<bridgehead id="preface-conv-typographic"
renderas="sect2">Typographic
Conventions</bridgehead>
<variablelist>
<varlistentry>
<term><emphasis>Italic</emphasis></term>
<listitem>
<para>An <emphasis>italic</emphasis> font is used for
filenames, URLs, emphasized text, and the first usage of
technical terms.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><literal>Monospace</literal></term>
<listitem>
<para>A <literal>monospaced</literal> font is
used for error messages, commands, environment variables,
names of ports, hostnames, user names, group names, device
names, variables, and code fragments.</para>
</listitem>
</varlistentry>
<varlistentry>
<term><application>Bold</application></term>
<listitem>
<para>A <application>bold</application> font is used for
applications, commands, and keys.</para>
</listitem>
</varlistentry>
</variablelist>
<!-- Var list -->
<bridgehead id="preface-conv-commands"
renderas="sect2">User Input</bridgehead>
<para>Keys are shown in <keycap>bold</keycap> to stand out from
other text. Key combinations that are meant to be typed
simultaneously are shown with `<literal>+</literal>' between
the keys, such as:</para>
<para>
<keycombo action="simul">
<keycap>Ctrl</keycap>
<keycap>Alt</keycap>
<keycap>Del</keycap></keycombo></para>
<para>Meaning the user should type the <keycap>Ctrl</keycap>,
<keycap>Alt</keycap>, and <keycap>Del</keycap> keys at the same
time.</para>
<para>Keys that are meant to be typed in sequence will be separated
with commas, for example:</para>
<para>
<keycombo action="simul">
<keycap>Ctrl</keycap>
<keycap>X</keycap>
</keycombo>,
<keycombo action="simul">
<keycap>Ctrl</keycap>
<keycap>S</keycap></keycombo></para>
<para>Would mean that the user is expected to type the
<keycap>Ctrl</keycap> and <keycap>X</keycap> keys simultaneously
and then to type the <keycap>Ctrl</keycap> and <keycap>S</keycap>
keys simultaneously.</para>
<!-- How to type in key stokes, etc.. -->
<bridgehead id="preface-conv-examples"
renderas="sect2">Examples</bridgehead>
<para>Examples starting with <devicename>E:\></devicename>
indicate a &ms-dos; command. Unless otherwise noted, these
commands may be executed from a <quote>Command Prompt</quote>
window in a modern µsoft.windows;
environment.</para>
<screen><prompt>E:\></prompt> <userinput>tools\fdimage floppies\kern.flp A:</userinput></screen>
<para>Examples starting with &prompt.root; indicate a command that
must be invoked as the superuser in &os;. You can login as
<username>root</username> to type the command, or login as your
normal account and use &man.su.1; to gain
superuser privileges.</para>
<screen>&prompt.root; <userinput>dd if=kern.flp of=/dev/fd0</userinput></screen>
<para>Examples starting with &prompt.user; indicate a command that
should be invoked from a normal user account. Unless otherwise
noted, C-shell syntax is used for setting environment variables
and other shell commands.</para>
<screen>&prompt.user; <userinput>top</userinput></screen>
<bridgehead id="preface-acknowledgements"
renderas="sect1">Acknowledgments</bridgehead>
<para>The book you are holding represents the efforts of many
hundreds of people around the world. Whether they sent in fixes
for typos, or submitted complete chapters, all the contributions
have been useful.</para>
<para>Several companies have supported the development of this
document by paying authors to work on it full-time, paying for
publication, etc. In particular, BSDi (subsequently acquired by
<ulink url="http://www.windriver.com">Wind River Systems</ulink>)
paid members of the &os; Documentation Project to work on
improving this book full time leading up to the publication of the
first printed edition in March 2000 (ISBN 1-57176-241-8). Wind
River Systems then paid several additional authors to make a
number of improvements to the print-output infrastructure and
to add additional chapters to the text. This work culminated in
the publication of the second printed edition in November 2001
(ISBN 1-57176-303-1). In 2003-2004, <ulink
url="http://www.freebsdmall.com">&os; Mall, Inc</ulink>, paid
several contributors to improve the Handbook in preparation for
the third printed edition.</para>
</preface>