HDFS-17634. RBF: Fix web UI missing DN last block report

Author: Felix Nguyen

hadoop-hdfs-project/hadoop-hdfs-rbf/src/main/java/org/apache/hadoop/hdfs/server/federation/metrics/NamenodeBeanMetrics.java

@@ -492,6 +492,7 @@ private String getNodesImpl(final DatanodeReportType type) {
         innerinfo.put("volfails", -1); // node.getVolumeFailures()
         innerinfo.put("blockPoolUsedPercentStdDev",
             Util.getBlockPoolUsedPercentStdDev(storageReports));
+        innerinfo.put("lastBlockReport", getLastBlockReport(node));
         info.put(node.getXferAddrWithHostname(),
             Collections.unmodifiableMap(innerinfo));
       }
@@ -795,6 +796,10 @@ private long getLastContact(DatanodeInfo node) {
     return (now() - node.getLastUpdate()) / 1000;
   }
 
+  private long getLastBlockReport(DatanodeInfo node) {
+    return (now() - node.getLastBlockReportTime()) / 60000;
+  }
+
   /////////////////////////////////////////////////////////
   // NameNodeStatusMXBean
   /////////////////////////////////////////////////////////