LUDOC-54 option: Documented lfs_migrate -c <stripe_count> option.

Updated lfs_migrate options in Section 32.2. Enhanced note in
Chapter 16 "Upgrading" about disabling wide striping on an MDS
to be downgraded.

Signed-off-by: Linda Bebernes <linda.bebernes@intel.com>
Change-Id: I1c945ad775d89eadb508951ab6ff3d071788229e
Reviewed-on: http://review.whamcloud.com/7687
Tested-by: Hudson
Reviewed-by: Jian Yu <jian.yu@intel.com>
Reviewed-by: Richard Henwood <richard.henwood@intel.com>

diff --git a/UpgradingLustre.xml b/UpgradingLustre.xml
index a7738e9..41fa15e 100644 (file)
--- a/UpgradingLustre.xml
+++ b/UpgradingLustre.xml
@@ -73,18 +73,34 @@
     <note>
       <para condition="l22">In Lustre release 2.2, a feature has been added that allows striping
         across up to 2000 OSTs. By default, this "wide striping" feature is disabled. It is
-        activated by setting the <literal>large-xattr</literal> option on the MDT using either
+        activated by setting the <literal>large_xattr</literal> option on the MDT using either
           <literal>mkfs.lustre</literal> or <literal>tune2fs</literal>. For example after upgrading
         an existing file system to Lustre release 2.2 or later, wide striping can be enabled by
         running the following command on the MDT device before mounting
         it:<screen>tune2fs -O large_xattr</screen>Once the wide striping feature is enabled and in
         use on the MDT, it is not possible to directly downgrade the MDT file system to an earlier
-        version of the Lustre software that does not support wide striping. The only way to disable
-        wide striping is to delete all files with a <literal>large_xattr</literal> extended attribute,
-       unmount the MDT, and run the following command to
-        turn off the <literal>large-xattr</literal>
-        option:<screen>tune2fs -O ^large_xattr</screen>
-       </para></note>
+        version of the Lustre software that does not support wide striping. To disable wide striping:<orderedlist>
+          <listitem>
+            <para>Delete all wide-striped files. </para>
+            <para>OR </para>
+            <para>Use <literal>lfs_migrate</literal> with the option <literal>-c</literal>
+              <replaceable>stripe_count</replaceable> (set <replaceable>stripe_count</replaceable>
+              to 160) to move the files to another location.</para>
+          </listitem>
+          <listitem>
+            <para>Unmount the MDT.</para>
+          </listitem>
+          <listitem>
+            <para>Run the following command to turn off the <literal>large_xattr</literal>
+              option:<screen>tune2fs -O ^large_xattr</screen></para>
+          </listitem>
+        </orderedlist>
+      </para></note>
+    <note condition="l23">
+      <para>To generate a list of all files with more than 160 stripes use <literal>lfs
+          find</literal> with the <literal>--stripe-count</literal>
+        option:<screen>lfs find ${mountpoint} --stripe-count=+160</screen></para>
+    </note>
     <note condition="l24">
       <para>In Lustre release 2.4, a new feature allows using multiple MDTs, which can each serve
         one or more remote sub-directories in the file system. The <literal>root</literal> directory

diff --git a/UserUtilities.xml b/UserUtilities.xml
index ea242ea..ac9ff93 100644 (file)
--- a/UserUtilities.xml
+++ b/UserUtilities.xml
@@ -660,7 +660,7 @@ lfs help
     <para>The <literal>lfs_migrate</literal> utility is a simple tool to migrate files between Lustre OSTs.</para>
     <section remap="h5">
       <title>Synopsis</title>
-      <screen>lfs_migrate [-c|-s] [-h] [-l] [-n] [-y] [file|directory ...]</screen>
+      <screen>lfs_migrate [-c <replaceable>stripecount</replaceable>] [-h] [-l] [-n] [-q] [-R] [-s] [-y] [file|directory ...]</screen>
     </section>
     <section remap="h5">
       <title>Description</title>
@@ -689,26 +689,21 @@ lfs help
           <tbody>
             <row>
               <entry>
-                <para> <literal>-c</literal></para>
-              </entry>
-              <entry>
-                <para>Compares file data after migrate (default value, use <literal>-s</literal> to disable).</para>
-              </entry>
-            </row>
-            <row>
-              <entry>
-                <para> <literal>-s</literal></para>
+                <para>
+                  <literal>-c <replaceable>stripecount</replaceable></literal></para>
               </entry>
               <entry>
-                <para>Skips file data comparison after migrate (use <literal>-c</literal> to enable).</para>
+                <para>Restripe file using the specified stripe count. This option may not be
+                  specified at the same time as the <literal>-R</literal> option.</para>
               </entry>
             </row>
             <row>
               <entry>
-                <para> <literal>-h</literal></para>
+                <para>
+                  <literal>-h</literal></para>
               </entry>
               <entry>
-                <para>Displays help information.</para>
+                <para>Display help information.</para>
               </entry>
             </row>
             <row>
@@ -716,7 +711,9 @@ lfs help
                 <literal>-l</literal>
               </entry>
               <entry>
-                <para>Migrates files with hard links (skips, by default). Files with multiple hard links are split into multiple separate files by <literal>lfs_migrate</literal>, so they are skipped, by default, to avoid breaking the hard links.</para>
+                <para>Migrate files with hard links (skips, by default). Files with multiple hard
+                  links are split into multiple separate files by <literal>lfs_migrate</literal>, so
+                  they are skipped, by default, to avoid breaking the hard links.</para>
               </entry>
             </row>
             <row>
@@ -724,7 +721,7 @@ lfs help
                 <literal>-n</literal>
               </entry>
               <entry>
-                <para>Only prints the names of files to be migrated.</para>
+                <para>Only print the names of files to be migrated.</para>
               </entry>
             </row>
             <row>
@@ -732,15 +729,29 @@ lfs help
                 <para> <literal>-q</literal></para>
               </entry>
               <entry>
-                <para>Runs quietly (does not print filenames or status).</para>
+                <para>Run quietly (does not print filenames or status).</para>
               </entry>
             </row>
             <row>
+              <entry><literal>-R</literal></entry>
+              <entry>Restripe file using default directory striping instead of keeping striping.
+                This option may not be specified at the same time as the <literal>-c</literal>
+                option.</entry>
+            </row>
+            <row>
+              <entry>
+                <literal>-s</literal></entry>
+              <entry>Skip file data comparison after migrate. Default is to compare migrated file
+                against original to verify correctness.</entry>
+            </row>
+            <row>
               <entry>
-                <para> <literal>--y</literal></para>
+                <para>
+                  <literal>-y</literal></para>
               </entry>
               <entry>
-                <para>Answers &apos;<literal>y</literal>&apos; to usage warning without prompting (for scripts).</para>
+                <para>Answer &apos;<literal>y</literal>&apos; to usage warning without prompting
+                  (for scripts, use with caution).</para>
               </entry>
             </row>
           </tbody>