HDFS-6060. NameNode should not check DataNode layout version. Contributed by Brandon Li

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1575021 13f79535-47bb-0310-9956-ffa450edef68

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

@@ -703,6 +703,8 @@ Release 2.4.0 - UNRELEASED
     HDFS-6059. TestBlockReaderLocal fails if native library is not available.
     (Akira AJISAKA via Colin Patrick McCabe)
 
+    HDFS-6060. NameNode should not check DataNode layout version (brandonli)
+
   BREAKDOWN OF HDFS-5698 SUBTASKS AND RELATED JIRAS
 
     HDFS-5717. Save FSImage header in protobuf. (Haohui Mai via jing9)

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/NameNodeRpcServer.java

@@ -104,7 +104,6 @@ import org.apache.hadoop.hdfs.security.token.delegation.DelegationTokenIdentifie
 import org.apache.hadoop.hdfs.server.blockmanagement.BlockManager;
 import org.apache.hadoop.hdfs.server.common.HdfsServerConstants.NamenodeRole;
 import org.apache.hadoop.hdfs.server.common.IncorrectVersionException;
-import org.apache.hadoop.hdfs.server.datanode.DataNodeLayoutVersion;
 import org.apache.hadoop.hdfs.server.namenode.NameNode.OperationCategory;
 import org.apache.hadoop.hdfs.server.namenode.metrics.NameNodeMetrics;
 import org.apache.hadoop.hdfs.server.namenode.web.resources.NamenodeWebHdfsMethods;
@@ -1100,20 +1099,6 @@ class NameNodeRpcServer implements NamenodeProtocols {
           + " but the expected ID is " + expectedID);
        throw new UnregisteredNodeException(nodeReg);
     }
-
-    // verify layout version if there is no rolling upgrade.
-    if (!namesystem.isRollingUpgrade()) {
-      final int lv = nodeReg.getVersion();
-      final int expectedLV = nodeReg instanceof NamenodeRegistration?
-          NameNodeLayoutVersion.CURRENT_LAYOUT_VERSION
-          : DataNodeLayoutVersion.CURRENT_LAYOUT_VERSION;
-      if (expectedLV != nodeReg.getVersion()) {
-        LOG.warn("Layout versions mismatched: the "
-            + nodeReg.getClass().getSimpleName() + " LV is " + lv
-            + " but the expected LV is " + expectedLV);
-         throw new UnregisteredNodeException(nodeReg);
-      }
-    }
   }
 
   @Override // RefreshAuthorizationPolicyProtocol