os/doc
3
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

Grammer: conciseness. Remove dead words.

Browse source
This commit is contained in:
Tom Rhodes 2002-10-03 20:56:40 +00:00
parent e93e6d4c7b
commit 937f502a6a
Notes: svn2git 2020-12-08 03:00:23 +00:00 
svn path=/head/; revision=14468
1 changed files with 25 additions and 25 deletions
Download patch file Download diff file Expand all files Collapse all files

50
en_US.ISO8859-1/books/handbook/disks/chapter.sgml
View file

@ -2080,23 +2080,23 @@ Filesystem 1K-blocks Used Avail Capacity Mounted on
<para>FreeBSD&nbsp;5.0 offers a new feature in conjunction with
<link linkend="soft-updates">Soft Updates</link>: File system snapshots.</para>
<para>Snapshots allow a user to create an image of specified file
systems and treat this image as a file.
<para>Snapshots allow a user to create images of specified file
systems, and treat them as a file.
Snapshot files must be created in the file system that the
action is performed on, and a user may create no more than 20
snapshots per file system. Active snapshots are recorded
in the superblock so they are persistent across unmount and
remount operations along with system reboots. When a snapshot
is no longer required, it can be removed with the standard &man.rm.1;
command, like regular files. Snapshots may be removed in any order,
however all the used space may not be acquired as another snapshot will
possibly claim some of the blocks that were released.</para>
command. Snapshots may be removed in any order,
however all the used space may not be acquired because another snapshot will
possibly claim some of the released blocks.</para>
<para>During initial creation, the <option>schg</option> flag (see &man.chflags.1; manual page)
is set on to ensure that not even <username>root</username> can write to the snapshot.
The &man.unlink.1; command makes an exception for snapshot files,
however, in which it allows them to be removed even
though they have the <option>schg</option> flag set, so it is not necessary to
is set to ensure that even <username>root</username> cannot write to the snapshot.
The &man.unlink.1; command makes an exception for snapshot files
since it allows them to be removed even
with the <option>schg</option> flag set, so it is not necessary to
clear the <option>schg</option> flag before removing a snapshot file.</para>
<para>Snapshots are created with the &man.mount.8; command. To place
@ -2106,38 +2106,38 @@ Filesystem 1K-blocks Used Avail Capacity Mounted on
<screen>&prompt.root; <userinput>mount -u -o snapshot /var/snapshot/snap /var</userinput></screen>
<para>Once a snapshot has been created, there are several interesting
things that an administrator can do with them:</para>
<para>Once a snapshot has been created, they have several
uses:</para>
<itemizedlist>
<listitem>
<para>Some administrators will use a snapshot file for backup purposes,
where the snapshot can be transfered to a CD or tape.</para>
because the snapshot can be transfered to CDs or tape.</para>
</listitem>
<listitem>
<para>File integrity, &man.fsck.8; may be ran on the snapshot file.
<para>File integrity, &man.fsck.8; may be ran on the snapshot.
Assuming that the file system was clean when it was mounted, you
should always get a clean (and unchanging) result from running
&man.fsck.8; on the snapshot. This is essentially what the
should always get a clean (and unchanging) result.
This is essentially what the
background &man.fsck.8; process does.</para>
</listitem>
<listitem>
<para>Run the &man.dump.8; utility on the snapshot.
A dump will be returned that is as consistent with the
file system as the timestamp of the snapshot.</para>
A dump will be returned that is consistent with the
file system and the timestamp of the snapshot.</para>
<warning><para>As of this writing &man.dump.8; has not yet
been changed to set the <filename>dumpdates</filename> file correctly, so
do not use this feature in production until that fix
is made.</para></warning>
<warning><para>As of this writing &man.dump.8; cannot
set the <filename>dumpdates</filename> file correctly.
Use of this feature is not recommended.
</para></warning>
</listitem>
<listitem>
<para>&man.mount.8; the snapshot as a frozen image of the file system.
To &man.mount.8; the snapshot
<filename>/var/snapshot/snap</filename>:</para>
<filename>/var/snapshot/snap</filename> run:</para>
<screen>&prompt.root; <userinput>mdconfig -a -t vnode -f /var/snapshot/snap -u 4</userinput></screen>
<screen>&prompt.root; <userinput>mount -r /dev/md4 /mnt</userinput></screen>
@ -2148,7 +2148,7 @@ Filesystem 1K-blocks Used Avail Capacity Mounted on
<para>You can now walk the hierarchy of your frozen <filename>/var</filename>
file system mounted at <filename>/mnt</filename>. Everything will
be in the same state it was during the snapshot creation time.
The only exception being that any earlier snapshots will appear
The only exception is that any earlier snapshots will appear
as zero length files. When the use of a snapshot has delimited,
it can be unmounted with:</para>
@ -2158,7 +2158,7 @@ Filesystem 1K-blocks Used Avail Capacity Mounted on
<para>For more information about <option>softupdates</option> and
file system snapshots, including technical papers, you can visit
Marshall Kirk McKusick's website at
<ulink url="http://www.mckusick.com/">http://www.mckusick.com</ulink></para>
<ulink url="http://www.mckusick.com/">http://www.mckusick.com.</ulink></para>
</sect1>
<sect1 id="quotas">