Add an explanation about using the barrier option in fstab. Fixes #2318.

git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@8881 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689

chapter01/changelog.xml

@@ -40,6 +40,12 @@
     <listitem>
       <para>2009-05-16</para>
       <itemizedlist>
+        <listitem>
+          <para>[bdubbs] - Add an explanation about using the barrier
+          option in fstab.
+          Fixes
+          <ulink url="&lfs-ticket-root;2318">#2318</ulink>.</para>
+        </listitem>
         <listitem>
           <para>[bdubbs] - Add zlib-1.2.3-fPIC-1.patch which allows
           building static and dynamic libraries in one step.  Also

chapter08/fstab.xml

@@ -95,4 +95,19 @@ EOF</userinput></screen>
   <!-- Personally, I find it more foolproof to always specify the iocharset and
   codepage in /etc/fstab for MS-based filesystems - Alexander E. Patrakov -->
 
+  <para>It is possible to make the ext3 filesystem reliable across power
+  failures for some hard disk types.  To do this, add the
+  <option>barrier=1</option> mount option to the appropriate entry in
+  <filename>/etc/fstab</filename>.  To check if the disk drive supports
+  this option, run 
+  <ulink url="http://www.linuxfromscratch.org/blfs/view/cvs/general/hdparm.html">hdparm</ulink>
+  on the applicable disk drive.  For example, if:</para>
+
+<screen><userinput>hdparm -I /dev/sda | grep NCQ</userinput></screen>
+
+  <para>returns non-empty output, the option is supported.</para>
+
+  <para>Note: Logical Volume Management (LVM) based partitions cannot use the
+  <option>barrier</option> option.</para>
+
 </sect1>