title: hadoop error not able to place enough replicas
body: <p>I am using hadoop 1.2.1. It was active for about 2 years. Now following error start to appear in logs and hbase 0.94.14 could not connect with it. </p>
  
  <p>NameNode Error:</p>
  
  <pre><code>2016-03-09 11:57:23,965 WARN org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Not able to place enough replicas, still in need of 1 to reach 2
  Not able to place enough replicas
  2016-03-09 11:57:23,965 WARN org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Not able to place enough replicas, still in need of 1 to reach 2
  Not able to place enough replicas
  2016-03-09 11:57:23,965 WARN org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Not able to place enough replicas, still in need of 1 to reach 2
  Not able to place enough replicas
  2016-03-09 11:57:26,966 WARN org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Not able to place enough replicas, still in need of 1 to reach 2
  Not able to place enough replicas
  </code></pre>
  
  <p>And in hbase master log file error is like following</p>
  
  <pre><code>2016-03-09 11:16:31,192 INFO org.apache.hadoop.hbase.master.AssignmentManager$TimeoutMonitor: node1,12000,1457504177336.timeoutMonitor exiting
  2016-03-09 11:16:31,193 INFO org.apache.hadoop.hbase.master.SplitLogManager$TimeoutMonitor: node1,12000,1457504177336.splitLogManagerTimeoutMonitor exiting
  2016-03-09 11:16:31,192 INFO org.apache.hadoop.hbase.master.AssignmentManager$TimerUpdater: node1,12000,1457504177336.timerUpdater exiting
  2016-03-09 11:16:31,218 INFO org.apache.zookeeper.ZooKeeper: Session: 0x2535a0114bb0001 closed
  2016-03-09 11:16:31,218 INFO org.apache.zookeeper.ClientCnxn: EventThread shut down
  2016-03-09 11:16:31,218 INFO org.apache.hadoop.hbase.master.HMaster: HMaster main thread exiting
  2016-03-09 11:16:31,218 ERROR org.apache.hadoop.hbase.master.HMasterCommandLine: Failed to start master
  java.lang.RuntimeException: HMaster Aborted
          at org.apache.hadoop.hbase.master.HMasterCommandLine.startMaster(HMasterCommandLine.java:160)
          at org.apache.hadoop.hbase.master.HMasterCommandLine.run(HMasterCommandLine.java:104)
          at org.apache.hadoop.util.ToolRunner.run(ToolRunner.java:65)
          at org.apache.hadoop.hbase.util.ServerCommandLine.doMain(ServerCommandLine.java:76)
          at org.apache.hadoop.hbase.master.HMaster.main(HMaster.java:2120)
  Wed Mar  9 11:22:26 PKT 2016 Stopping hbase (via master)
  </code></pre>
  
  <p>where is the problem. I have found a post who suggest that you should delete all data and format namdenode but I cannot do that as I cannot backup data.</p>
  
  <p>This is the cluster summery</p>
  
  <pre><code>Configured Capacity: 3293363527680 (3 TB)
  Present Capacity: 2630143946752 (2.39 TB)
  DFS Remaining: 1867333337088 (1.7 TB)
  DFS Used: 762810609664 (710.42 GB)
  DFS Used%: 29%
  Under replicated blocks: 35
  Blocks with corrupt replicas: 0
  Missing blocks: 0
  
  -------------------------------------------------
  Datanodes available: 3 (3 total, 0 dead)
  
  Name: 10.11.21.44:50010
  Decommission Status : Normal
  Configured Capacity: 441499058176 (411.18 GB)
  DFS Used: 246261780480 (229.35 GB)
  Non DFS Used: 194947321856 (181.56 GB)
  DFS Remaining: 289955840(276.52 MB)
  DFS Used%: 55.78%
  DFS Remaining%: 0.07%
  Last contact: Thu Mar 10 15:20:15 PKT 2016
  
  
  Name: 10.11.21.42:50010
  Decommission Status : Normal
  Configured Capacity: 2410365411328 (2.19 TB)
  DFS Used: 304959569920 (284.02 GB)
  Non DFS Used: 238646935552 (222.26 GB)
  DFS Remaining: 1866758905856(1.7 TB)
  DFS Used%: 12.65%
  DFS Remaining%: 77.45%
  Last contact: Thu Mar 10 15:20:15 PKT 2016
  
  
  Name: 10.11.21.43:50010
  Decommission Status : Normal
  Configured Capacity: 441499058176 (411.18 GB)
  DFS Used: 211589259264 (197.06 GB)
  Non DFS Used: 229625323520 (213.86 GB)
  DFS Remaining: 284475392(271.3 MB)
  DFS Used%: 47.93%
  DFS Remaining%: 0.06%
  Last contact: Thu Mar 10 15:20:16 PKT 2016
  </code></pre>