HDFS-2502. svn merge -c 1204117 from trunk

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.23@1204118 13f79535-47bb-0310-9956-ffa450edef68

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -32,8 +32,11 @@ Release 0.23.1 - UNRELEASED
   BUG FIXES
 
     HDFS-2541. For a sufficiently large value of blocks, the DN Scanner 
-    may request a random number with a negative seed value. (harsh)
+    may request a random number with a negative seed value. (harsh via eli)
 
+    HDFS-2502. hdfs-default.xml should include dfs.name.dir.restore.
+    (harsh via eli)
+    
 Release 0.23.0 - 2011-11-01 
 
   INCOMPATIBLE CHANGES

hadoop-hdfs-project/hadoop-hdfs/src/main/resources/hdfs-default.xml

@@ -193,6 +193,14 @@ creations/deletions), or "all".</description>
       directories, for redundancy. </description>
 </property>
 
+<property>
+  <name>dfs.namenode.name.dir.restore</name>
+  <value>false</value>
+  <description>Set to true to enable NameNode to attempt recovering a
+      previously failed dfs.name.dir. When enabled, a recovery of any failed
+      directory is attempted during checkpoint.</description>
+</property>
+
 <property>
   <name>dfs.namenode.fs-limits.max-component-length</name>
   <value>0</value>