/usr/share/doc/sysadmin-guide/html/root-fs.html

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>3.2. The root filesystem</H1
><P
>The root filesystem should generally be small, since
	it contains very critical files and a small, infrequently
	modified filesystem has a better chance of not getting corrupted.
	A corrupted root filesystem will generally mean that the system
	becomes unbootable except with special measures (e.g., from a
	floppy), so you don't want to risk it.</P
><P
>The root directory generally doesn't contain any files, except
	perhaps on older systems where the standard boot image for the system, 
	usually called <TT
CLASS="FILENAME"
>/vmlinuz</TT
>
	 was kept there.  (Most 
	distributions have moved those files the the 
	<TT
CLASS="FILENAME"
>/boot</TT
> directory.  Otherwise, all files are kept
	in subdirectories under the root filesystem:

	<DIV
CLASS="GLOSSLIST"
><DL
><DT
><B
><TT
CLASS="FILENAME"
>/bin</TT
></B
></DT
><DD
><P
>Commands needed during bootup
		that might be used by normal users (probably after
		bootup).</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/sbin</TT
></B
></DT
><DD
><P
>Like <TT
CLASS="FILENAME"
>/bin</TT
>, but the
		commands are not intended for normal users, although they
		may use them if necessary and allowed.
		<TT
CLASS="FILENAME"
>/sbin</TT
> is not usually in the default
		path of normal users, but will be in root's default
		path.</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/etc</TT
></B
></DT
><DD
><P
>Configuration files specific to the
		machine.</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/root</TT
></B
></DT
><DD
><P
>The home directory for user root.  This is
		usually not accessible to other users on the
		system</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/lib</TT
></B
></DT
><DD
><P
>Shared libraries needed by the programs on
		the root filesystem.</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/lib/modules</TT
></B
></DT
><DD
><P
>Loadable kernel modules, especially those
		that are needed to boot the system when recovering from
		disasters (e.g., network and filesystem
		drivers).</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/dev</TT
></B
></DT
><DD
><P
>Device files.  These are special files that 
		help the user interface with the various devices on the system.
		</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/tmp</TT
></B
></DT
><DD
><P
>Temporary files.  As the name suggests,
		programs running often store temporary files in here.
		</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/boot</TT
></B
></DT
><DD
><P
>Files used by the bootstrap loader,
		e.g., LILO or GRUB.  Kernel images are often kept here instead
		of in the root directory.  If there are many kernel
		images, the directory can easily grow rather big, and it
		might be better to keep it in a separate filesystem.
		Another reason would be to make sure the kernel
		images are within the first 1024 cylinders of an IDE
		disk. This 1024 cylinder limit is no longer true in 
		most cases.  With modern BIOSes and later versions of LILO
		(the LInux LOader) the 1024 cylinder limit can be passed 
		with logical block addressing (LBA).  See the 
		<B
CLASS="COMMAND"
>lilo</B
> manual page for more details.
	       </P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/mnt</TT
></B
></DT
><DD
><P
>Mount point for temporary mounts by
		the system administrator.  Programs aren't supposed to mount
		on <TT
CLASS="FILENAME"
>/mnt</TT
> automatically.
		<TT
CLASS="FILENAME"
>/mnt</TT
> might be divided into
		subdirectories (e.g., <TT
CLASS="FILENAME"
>/mnt/dosa</TT
> might
		be the floppy drive using an MS-DOS filesystem, and
		<TT
CLASS="FILENAME"
>/mnt/exta</TT
> might be the same
		with an ext2 filesystem).</P
></DD
><DT
><B
><TT
CLASS="FILENAME"
>/proc</TT
>,
	<TT
CLASS="FILENAME"
>/usr</TT
>, 
	<TT
CLASS="FILENAME"
>/var</TT
>,
	<TT
CLASS="FILENAME"
>/home</TT
></B
></DT
><DD
><P
>Mount points for the other filesystems.  Although
	<TT
CLASS="FILENAME"
>/proc</TT
> does not reside on any disk in reality
	it is still mentioned here. See the section about 
	<TT
CLASS="FILENAME"
>/proc</TT
> later in the chapter.
	</P
></DD
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sysadmin-guide 0.9-1 / usr / share / doc / sysadmin-guide / html / root-fs.html
