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Changed mfs(8) to mdmfs(8) for non-4.X. Also:

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= Overhauled /tmp/ entry that it was in.
= Changed "filesystem" to FDP "file system".
= Added 'valign="top"' to two "tbody" tags so "label" (eg, /tmp/)
  is on is on the same line as the start of its description.
= DocBook'd "NOT".

Approved by:    keramida
This commit is contained in:
Gary W. Swearingen 2005-09-13 18:37:25 +00:00
parent 817beb263e
commit c7149747e8
Notes: svn2git 2020-12-08 03:00:23 +00:00 
svn path=/head/; revision=25636
1 changed files with 53 additions and 51 deletions

104
en_US.ISO8859-1/books/handbook/basics/chapter.sgml
View file

@ -662,7 +662,7 @@ total 530
<entry>Description</entry>
</row>
</thead>
<tbody>
<tbody valign="top">
<row>
<entry><filename class="directory">/</filename></entry>
<entry>Root directory of the file system.</entry>
@ -763,10 +763,12 @@ total 530
<row>
<entry><filename class="directory">/tmp/</filename></entry>
<entry>Temporary files, usually a &man.mfs.8;
memory-based file system (the contents of <filename
class="directory">/tmp</filename> are usually NOT
preserved across a system reboot).</entry>
<entry>Temporary files. The contents of
<filename class="directory">/tmp</filename> are usually NOT
preserved across a system reboot. A memory-based file system
is often mounted at
<filename class="directory">/tmp</filename>. See &man.mdmfs.8;
(or &man.mfs.8; for FreeBSD&nbsp;4.X).</entry>
</row>
@ -917,9 +919,9 @@ total 530
<firstterm>path</firstterm> to the file is
<filename>foo/bar/readme.txt</filename>.</para>
<para>Directories and files are stored in a filesystem. Each filesystem
<para>Directories and files are stored in a file system. Each file system
contains exactly one directory at the very top level, called the
<firstterm>root directory</firstterm> for that filesystem. This root
<firstterm>root directory</firstterm> for that file system. This root
directory can then contain other directories.</para>
<para>So far this is probably similar to any other operating system you
@ -931,21 +933,21 @@ total 530
path. You would not write <filename>c:/foo/bar/readme.txt</filename>
on FreeBSD.</para>
<para>Instead, one filesystem is designated the <firstterm>root
filesystem</firstterm>. The root filesystem's root directory is
referred to as <literal>/</literal>. Every other filesystem is then
<firstterm>mounted</firstterm> under the root filesystem. No matter
<para>Instead, one file system is designated the <firstterm>root
file system</firstterm>. The root file system's root directory is
referred to as <literal>/</literal>. Every other file system is then
<firstterm>mounted</firstterm> under the root file system. No matter
how many disks you have on your FreeBSD system, every directory
appears to be part of the same disk.</para>
<para>Suppose you have three filesystems, called <literal>A</literal>,
<literal>B</literal>, and <literal>C</literal>. Each filesystem has
<para>Suppose you have three file systems, called <literal>A</literal>,
<literal>B</literal>, and <literal>C</literal>. Each file system has
one root directory, which contains two other directories, called
<literal>A1</literal>, <literal>A2</literal> (and likewise
<literal>B1</literal>, <literal>B2</literal> and
<literal>C1</literal>, <literal>C2</literal>).</para>
<para>Call <literal>A</literal> the root filesystem. If you used the
<para>Call <literal>A</literal> the root file system. If you used the
<command>ls</command> command to view the contents of this directory
you would see two subdirectories, <literal>A1</literal> and
<literal>A2</literal>. The directory tree looks like this:</para>
@ -964,8 +966,8 @@ total 530
</textobject>
</mediaobject>
<para>A filesystem must be mounted on to a directory in another
filesystem. So now suppose that you mount filesystem
<para>A file system must be mounted on to a directory in another
file system. So now suppose that you mount file system
<literal>B</literal> on to the directory <literal>A1</literal>. The
root directory of <literal>B</literal> replaces <literal>A1</literal>,
and the directories in <literal>B</literal> appear accordingly:</para>
@ -1019,10 +1021,10 @@ total 530
<para>and the paths would be <filename>/A2/B1</filename> and
<filename>/A2/B2</filename> respectively.</para>
<para>Filesystems can be mounted on top of one another. Continuing the
last example, the <literal>C</literal> filesystem could be mounted on
<para>File systems can be mounted on top of one another. Continuing the
last example, the <literal>C</literal> file system could be mounted on
top of the <literal>B1</literal> directory in the <literal>B</literal>
filesystem, leading to this arrangement:</para>
file system, leading to this arrangement:</para>
<mediaobject>
<imageobject>
@ -1047,7 +1049,7 @@ total 530
</mediaobject>
<para>Or <literal>C</literal> could be mounted directly on to the
<literal>A</literal> filesystem, under the <literal>A1</literal>
<literal>A</literal> file system, under the <literal>A1</literal>
directory:</para>
<mediaobject>
@ -1076,73 +1078,73 @@ total 530
identical, to the <command>join</command> command.</para>
<para>This is not normally something you need to concern yourself with.
Typically you create filesystems when installing FreeBSD and decide
Typically you create file systems when installing FreeBSD and decide
where to mount them, and then never change them unless you add a new
disk.</para>
<para>It is entirely possible to have one large root filesystem, and not
<para>It is entirely possible to have one large root file system, and not
need to create any others. There are some drawbacks to this approach,
and one advantage.</para>
<itemizedlist>
<title>Benefits of Multiple Filesystems</title>
<title>Benefits of Multiple File Systems</title>
<listitem>
<para>Different filesystems can have different <firstterm>mount
<para>Different file systems can have different <firstterm>mount
options</firstterm>. For example, with careful planning, the
root filesystem can be mounted read-only, making it impossible for
root file system can be mounted read-only, making it impossible for
you to inadvertently delete or edit a critical file. Separating
user-writable filesystems, such as <filename>/home</filename>,
from other filesystems also allows them to be mounted
user-writable file systems, such as <filename>/home</filename>,
from other file systems also allows them to be mounted
<firstterm>nosuid</firstterm>; this option prevents the
<firstterm>suid</firstterm>/<firstterm>guid</firstterm> bits on
executables stored on the filesystem from taking effect, possibly
executables stored on the file system from taking effect, possibly
improving security.</para>
</listitem>
<listitem>
<para>FreeBSD automatically optimizes the layout of files on a
filesystem, depending on how the filesystem is being used. So a
filesystem that contains many small files that are written
file system, depending on how the file system is being used. So a
file system that contains many small files that are written
frequently will have a different optimization to one that contains
fewer, larger files. By having one big filesystem this
fewer, larger files. By having one big file system this
optimization breaks down.</para>
</listitem>
<listitem>
<para>FreeBSD's filesystems are very robust should you lose power.
<para>FreeBSD's file systems are very robust should you lose power.
However, a power loss at a critical point could still damage the
structure of the filesystem. By splitting your data over multiple
filesystems it is more likely that the system will still come up,
structure of the file system. By splitting your data over multiple
file systems it is more likely that the system will still come up,
making it easier for you to restore from backup as necessary.</para>
</listitem>
</itemizedlist>
<itemizedlist>
<title>Benefit of a Single Filesystem</title>
<title>Benefit of a Single File System</title>
<listitem>
<para>Filesystems are a fixed size. If you create a filesystem when
<para>File systems are a fixed size. If you create a file system when
you install FreeBSD and give it a specific size, you may later
discover that you need to make the partition bigger. This is not
easily accomplished without backing up, recreating the filesystem
easily accomplished without backing up, recreating the file system
with the new size, and then restoring the backed up data.</para>
<important>
<para>FreeBSD&nbsp;4.4 and later versions feature the &man.growfs.8;
command, which makes it possible to increase the size of
filesystem on the fly, removing this limitation.</para>
file system on the fly, removing this limitation.</para>
</important>
</listitem>
</itemizedlist>
<para>Filesystems are contained in partitions. This does not have the
<para>File systems are contained in partitions. This does not have the
same meaning as the common usage of the term partition (for example, &ms-dos;
partition), because of &os;'s &unix; heritage. Each partition is
identified by a letter from <literal>a</literal> through to
<literal>h</literal>. Each partition can contain only one filesystem,
which means that filesystems are often described by either their
typical mount point in the filesystem hierarchy, or the letter of the
<literal>h</literal>. Each partition can contain only one file system,
which means that file systems are often described by either their
typical mount point in the file system hierarchy, or the letter of the
partition they are contained in.</para>
<para>FreeBSD also uses disk space for <firstterm>swap
@ -1169,11 +1171,11 @@ total 530
</row>
</thead>
<tbody>
<tbody valign="top">
<row>
<entry><literal>a</literal></entry>
<entry>Normally contains the root filesystem</entry>
<entry>Normally contains the root file system</entry>
</row>
<row>
@ -1189,7 +1191,7 @@ total 530
allows utilities that need to work on the entire slice (for
example, a bad block scanner) to work on the
<literal>c</literal> partition. You would not normally create
a filesystem on this partition.</entry>
a file system on this partition.</entry>
</row>
<row>
@ -1206,7 +1208,7 @@ total 530
</tgroup>
</informaltable>
<para>Each partition-that-contains-a-filesystem is stored in what
<para>Each partition-that-contains-a-file-system is stored in what
FreeBSD calls a <firstterm>slice</firstterm>. Slice is FreeBSD's term
for what the common call partitions, and again, this is because of
FreeBSD's &unix; background. Slices are numbered, starting at 1,
@ -1255,8 +1257,8 @@ total 530
<para>In order to install FreeBSD you must first configure the disk
slices, then create partitions within the slice you will use for
FreeBSD, and then create a filesystem (or swap space) in each
partition, and decide where that filesystem will be mounted.</para>
FreeBSD, and then create a file system (or swap space) in each
partition, and decide where that file system will be mounted.</para>
<table frame="none" pgwide="1" id="basics-dev-codes">
<title>Disk Device Codes</title>
@ -1354,8 +1356,8 @@ total 530
FreeBSD installation. This example FreeBSD installation has three
partitions, and a swap partition.</para>
<para>The three partitions will each hold a filesystem. Partition
<literal>a</literal> will be used for the root filesystem,
<para>The three partitions will each hold a file system. Partition
<literal>a</literal> will be used for the root file system,
<literal>e</literal> for the <filename>/var</filename> directory
hierarchy, and <literal>f</literal> for the
<filename>/usr</filename> directory hierarchy.</para>
@ -1381,7 +1383,7 @@ total 530
| | > referred to as ad0s2b |
| | | |
:-----------------: ==: | Partition c, no
| | | Partition e, used as /var > filesystem, all
| | | Partition e, used as /var > file system, all
| | > referred to as ad0s2e | of FreeBSD slice,
| | | | ad0s2c
:-----------------: ==: |