HDFS-9880. TestDatanodeRegistration fails occasionally. Contributed by Kihwal Lee.

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

@@ -2963,6 +2963,8 @@ Release 2.7.3 - UNRELEASED
     HDFS-9864. Correct reference for RENEWDELEGATIONTOKEN and
     CANCELDELEGATIONTOKEN in webhdfs doc. (Brahma Reddy Battula via aajisaka)
 
+    HDFS-9880. TestDatanodeRegistration fails occasionally (kihwal)
+
 Release 2.7.2 - 2016-01-25
 
   INCOMPATIBLE CHANGES

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDatanodeRegistration.java

@@ -324,7 +324,7 @@ public class TestDatanodeRegistration {
   // should not occur other than dead/unregistered node which will trigger a
   // re-registration.  If a non-IPC exception does occur, the safety net is
   // a forced re-registration on the next heartbeat.
-  @Test(timeout=10000)
+  @Test
   public void testForcedRegistration() throws Exception {
     final Configuration conf = new HdfsConfiguration();
     conf.setInt(DFSConfigKeys.DFS_NAMENODE_HANDLER_COUNT_KEY, 4);
@@ -439,10 +439,10 @@ public class TestDatanodeRegistration {
         public Boolean get() {
           return lastCount != storage.getBlockReportCount();
         }
-      }, 10, 100);
+      }, 10, 2000);
     } catch (TimeoutException te) {
       return false;
     }
     return true;
   }
-}
+}