Dear all,
I have a running 4-node Hadoop cluster and some data stored in HDFS.
Today by mistake,I start the hadoop cluster with root user.
root>bin/start-all.sh
After correcting my mistake , when I try to run with the hadoop user, my
Namenode fails with the below exception\ :
STARTUP_MSG: build =
https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.20 -r
911707; compiled by 'chrisdo' on Fri Feb 19 08:07:34 UTC 2010
************************************************************/
2011-04-28 10:53:49,516 INFO org.apache.hadoop.ipc.metrics.RpcMetrics:
Initializing RPC Metrics with hostName=NameNode, port=54310
2011-04-28 10:53:49,520 INFO
org.apache.hadoop.hdfs.server.namenode.NameNode: Namenode up at:
ws-test/192.168.0.207:54310
2011-04-28 10:53:49,523 INFO org.apache.hadoop.metrics.jvm.JvmMetrics:
Initializing JVM Metrics with processName=NameNode, sessionId=null
2011-04-28 10:53:49,527 INFO
org.apache.hadoop.hdfs.server.namenode.metrics.NameNodeMetrics:
Initializing NameNodeMeterics using context
object:org.apache.hadoop.metrics.ganglia.GangliaContext
2011-04-28 10:53:49,573 INFO
org.apache.hadoop.hdfs.server.namenode.FSNamesystem: fsOwner=hadoop,hadoop
2011-04-28 10:53:49,573 INFO
org.apache.hadoop.hdfs.server.namenode.FSNamesystem: supergroup=supergroup
2011-04-28 10:53:49,573 INFO
org.apache.hadoop.hdfs.server.namenode.FSNamesystem:
isPermissionEnabled=false
2011-04-28 10:53:49,580 INFO
org.apache.hadoop.hdfs.server.namenode.metrics.FSNamesystemMetrics:
Initializing FSNamesystemMetrics using context
object:org.apache.hadoop.metrics.ganglia.GangliaContext
2011-04-28 10:53:49,581 INFO
org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Registered
FSNamesystemStatusMBean
2011-04-28 10:53:49,608 ERROR
org.apache.hadoop.hdfs.server.namenode.FSNamesystem: FSNamesystem
initialization failed.
java.io.IOException: NameNode is not formatted.
at
org.apache.hadoop.hdfs.server.namenode.FSImage.recoverTransitionRead(FSImage.java:317)
at
org.apache.hadoop.hdfs.server.namenode.FSDirectory.loadFSImage(FSDirectory.java:87)
at
org.apache.hadoop.hdfs.server.namenode.FSNamesystem.initialize(FSNamesystem.java:311)
at
org.apache.hadoop.hdfs.server.namenode.FSNamesystem.<init>(FSNamesystem.java:292)
at
org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:201)
at
org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:279)
at
org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:956)
at
org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:965)
2011-04-28 10:53:49,609 INFO org.apache.hadoop.ipc.Server: Stopping
server on 54310
2011-04-28 10:53:49,609 ERROR
org.apache.hadoop.hdfs.server.namenode.NameNode: java.io.IOException:
NameNode is not formatted.
at
org.apache.hadoop.hdfs.server.namenode.FSImage.recoverTransitionRead(FSImage.java:317)
at
org.apache.hadoop.hdfs.server.namenode.FSDirectory.loadFSImage(FSDirectory.java:87)
at
org.apache.hadoop.hdfs.server.namenode.FSNamesystem.initialize(FSNamesystem.java:311)
at
org.apache.hadoop.hdfs.server.namenode.FSNamesystem.<init>(FSNamesystem.java:292)
at
org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:201)
at
org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:279)
at
org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:956)
at
org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:965)
2011-04-28 10:53:49,610 INFO
org.apache.hadoop.hdfs.server.namenode.NameNode: SHUTDOWN_MSG:
/************************************************************
I know if i delete the data & mapred directory of all node & issue the
bin/hadoop namenode -format command , my cluster starts again but
previous data lost.
Is it possible to start cluster without the data loss. If yes, Please
let me know
Thanks
