HDFS-6364. Incorrect check for unknown datanode in Balancer. (Contributed by Benoy Antony)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1601771 13f79535-47bb-0310-9956-ffa450edef68

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

@@ -666,6 +666,9 @@ Release 2.5.0 - UNRELEASED
     HDFS-6257. TestCacheDirectives#testExceedsCapacity fails occasionally
     (cmccabe)
 
+    HDFS-6364. Incorrect check for unknown datanode in Balancer. (Benoy
+    Antony via Arpit Agarwal)
+
 Release 2.4.1 - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/balancer/Balancer.java

@@ -696,7 +696,7 @@ public class Balancer {
             // update locations
             for (String datanodeUuid : blk.getDatanodeUuids()) {
               final BalancerDatanode d = datanodeMap.get(datanodeUuid);
-              if (datanode != null) { // not an unknown datanode
+              if (d != null) { // not an unknown datanode
                 block.addLocation(d);
               }
             }