<chapter id="intro">
<title>Introduction</title>
	<blockquote><para><quote>In the beginning, the file was without
	form, and void; and emptiness was upon the face of the bits.
	And the Fingers of the Author moved upon the face of the
	keyboard.  And the Author said, Let there be words, and there
	were words.</quote></para></blockquote>

	<para>The Linux System Administrator's Guide,
	describes the system administration aspects of using Linux.
	It is intended for people who know next to nothing about system
	administration (those saying ``what is it?''), but who have already
	mastered at least the basics of normal usage.  This manual
	doesn't tell you how to install Linux; that is described in the
	Installation and Getting Started document. See below for more
	information about Linux manuals.</para>

	<para>System administration covers all the things that you have to
	do to keep a computer system in usable order.  It includes
	things like backing up files (and restoring them if necessary),
	installing new programs, creating accounts for users (and deleting
	them when no longer needed), making certain that the filesystem
	is not corrupted, and so on.  If a computer were, say, a house,
	system administration would be called maintenance, and would
	include cleaning, fixing broken windows, and other such things.
	</para>

	<para>The structure of this manual is such that many of the
	chapters should be usable independently, so if you need information
	about backups, for example, you can read just that chapter. However,
	this manual is	first and foremost a tutorial and can be read
	sequentially or as a whole.</para>

	<para>This manual is not intended to be used completely 
	independently. Plenty of the rest of the Linux documentation is also
	important for system administrators.  After all, a system
	administrator is just a user with special privileges and duties.
	Very useful resources are the manual pages, which should always be
	consulted when you are not familiar with a command.  If you do not
	know which command you need, then the <command>apropos</command>
	command can be used.  Consult its manual page for more details.</para>

	<para>While this manual is targeted at Linux, a general principle
	has been that it should be useful with other UNIX based operating
	systems as well.  Unfortunately, since there is so much variance
	between different versions of UNIX in general, and in system
	administration in particular, there is little hope to cover
	all variants.  Even covering all possibilities for Linux is
	difficult, due to the nature of its development.</para>
	
	<para>There is no one official Linux distribution, so different
	people have different setups and many people have a setup they
	have built up themselves.  This book is not targeted at any
	one distribution.  Distributions can and do vary considerably.
	When possible, differences have been noted and alternatives
	given.  For a list of distributions <indexterm id="Linux-distro">
	<primary>Linux</primary><secondary>Distributions</secondary></indexterm>
	and some of their differences see
	<ulink url="http://en.wikipedia.org/wiki/Comparison_of_Linux_distributions">
	http://en.wikipedia.org/wiki/Comparison_of_Linux_distributions</ulink>.
	</para>
	
	<para>In trying to describe how things work, rather than just
	listing ``five easy steps'' for each task, there is much information
	here that is not necessary for everyone, but those parts are marked
	as such and can be skipped if you use a preconfigured system.
	Reading everything will, naturally, increase your understanding of
	the system and should make using and administering it more
	productive.</para>
		
	<para>Understanding is the key to success with Linux.  This book 
	could just provide recipes, but what would you do when confronted by 
	a problem this book had no recipe for?  If the book can provide
	understanding, then recipes are not required. The answers will be self 
	evident.</para>

	<para>Like all other Linux related development, the work 
	to write this manual was done on a volunteer basis: I did it because
	I thought it might be fun and because I felt it should be done.
	However, like all volunteer work, there is a limit to how much time,
	knowledge and experience people have.  This means that the manual is
	not necessarily as good as it would be if a wizard had been paid
	handsomely to write it
	and had spent millennia to perfect it.  Be warned.</para>

	<para>One particular point where corners have been cut is that 
	many things that are already well documented in other freely
	available manuals are not always covered here.  This applies
	especially to program specific documentation, such as all the
	details of using <command>mkfs</command>.  Only the purpose of the
	program and as much of its usage as is necessary for the purposes of
	this manual is described.  For further information, consult these
	other manuals.  Usually, all of the referred to documentation is
	part of the full Linux
	documentation set.</para>

<sect1 id="GNU-or-not">
<title>Linux or GNU/Linux, that is the question.</title>

	<para>Many people feel that Linux should really be called GNU/Linux.  
	<indexterm id="ch01-GNU-or-not"><primary>Linux</primary><secondary>GNU
	</secondary></indexterm>
	This is because Linux is only the kernel, not the applications that run 
	on it.  Most of the basic command line utilities were written by the
	Free Software Foundation while developing their GNU operating system.  
	Among those utilities are some of the most basic commands like cp, mv,
	lsof, and dd.</para>

	<para>In a nutshell, what happened was, the FSF <indexterm id="fsf">
	<primary>Free Software Foundation</primary></indexterm>started developing GNU
	by writing things like compliers, C libraries, and basic command line
	utilities before the kernel.  Linus Torvalds, started Linux by writing 
	the Linux kernel first and using applications written for GNU.</para>
	
	<para>I do not feel that this is the proper forum to debate what name
	people should use when referring to Linux.  I mention it here, because 
	I feel it is important to understand the relationship between GNU and
	Linux, and to also explain why some Linux is sometimes referred to as
	GNU/Linux.  The document will be simply referring to it as Linux.
	</para>

	<para>GNU's side of the issue is discussed on their website:</para> 

	<para>The relationship - 
	<ulink url="http://www.gnu.org/gnu/linux-and-gnu.html">
	http://www.gnu.org/gnu/linux-and-gnu.html</ulink></para>

	<para>Why Linux should be GNU/Linux - <ulink
	url="http://www.gnu.org/gnu/why-gnu-linux.html">
	http://www.gnu.org/gnu/why-gnu-linux.html</ulink></para>

	<para>GNU/Linux FAQ's - <ulink
	url="http://www.gnu.org/gnu/gnu-linux-faq.html">
	http://www.gnu.org/gnu/gnu-linux-faq.html</ulink></para>

	<para>Here are some Alternate views:</para>

	<para><ulink url="http://librenix.com/?inode=2312">
	http://librenix.com/?inode=2312</ulink></para>

	<para><ulink url="http://www.topology.org/linux/lingl.html">
	http://www.topology.org/linux/lingl.html</ulink></para>

	<para><ulink url="http://atulchitnis.net/writings/gnulinux.php">
	http://atulchitnis.net/writings/gnulinux.php</ulink></para>

</sect1>

<sect1>
<title>Trademarks</title>

	<para>Microsoft, Windows, Windows NT, Windows 2000, and Windows XP
	 are trademarks and/or registered trademarks of Microsoft Corporation.
	</para>

	<para>Red Hat is a trademark of Red Hat, Inc., in the United States 
	and other countries.</para>

	<para>SuSE is a trademark of Novell.</para>

	<para>Linux is a registered trademark of Linus Torvalds.</para>

	<para>UNIX is a registered trademark in the United States and other 
	countries, licensed exclusively through X/Open Company Ltd.</para>

	<para>GNU is a registered trademark of the Free Software Foundation.
	</para>

	<para>Other product names mentioned herein may be trademarks and/or 
	registered trademarks of their respective companies. </para>

</chapter>
