Hi Prabhu, Did you clean the data dir on DataNodes? Whenever Namenode is formated the data directories of Datanodes needs to be cleaned up. As far as i remember it's the directory which you mention in dfs.data.dir in hdfs-site.xml file.You can do a google search for the error and you can get more details. (Sorry, i dont have access to my cluster conf right now for telling you the exact property).
Thanks, Anil On Wed, Aug 8, 2012 at 12:49 AM, prabhu K <[email protected]> wrote: > Hi Users, > > I have formatted hadoop cluster, formatted successfully. after stop &start > hadoop, i hit the jps command in master, getting fine, but in slave machine > am not getting data node, while see the data node log file, i am getting > following error. > > Data node(slave1): > 2012-08-08 00:16:44,033 WARN > org.apache.hadoop.hdfs.server.datanode.DataBlockScanner: Second > Verification failed for blk_-3831635302961953167_1690. Exception : java.io > . > IOException: Block blk_-3831635302961953167_1690 is not valid. > at > org.apache.hadoop.hdfs.server.datanode.FSDataset.getBlockFile(FSDataset.java:1072) > at > org.apache.hadoop.hdfs.server.datanode.FSDataset.getLength(FSDataset.java:1035) > at > org.apache.hadoop.hdfs.server.datanode.FSDataset.getVisibleLength(FSDataset.java:1045) > at > org.apache.hadoop.hdfs.server.datanode.BlockSender.<init>(BlockSender.java:94) > at > org.apache.hadoop.hdfs.server.datanode.BlockSender.<init>(BlockSender.java:81) > at > org.apache.hadoop.hdfs.server.datanode.DataBlockScanner.verifyBlock(DataBlockScanner.java:453) > at > org.apache.hadoop.hdfs.server.datanode.DataBlockScanner.verifyFirstBlock(DataBlockScanner.java:519) > at > org.apache.hadoop.hdfs.server.datanode.DataBlockScanner.run(DataBlockScanner.java:617) > at java.lang.Thread.run(Thread.java:662) > > *data node(slave2)* > 2012-08-08 13:03:50,195 ERROR > org.apache.hadoop.hdfs.server.datanode.DataNode: java.io.IOException: > Incompatible namespaceIDs in /app/hadoop/tmp/dfs/data: namenode name > spaceID = 1434906924; datanode namespaceID = 474761520 > at > org.apache.hadoop.hdfs.server.datanode.DataStorage.doTransition(DataStorage.java:232) > at > org.apache.hadoop.hdfs.server.datanode.DataStorage.recoverTransitionRead(DataStorage.java:147) > at > org.apache.hadoop.hdfs.server.datanode.DataNode.startDataNode(DataNode.java:385) > at > org.apache.hadoop.hdfs.server.datanode.DataNode.<init>(DataNode.java:299) > at > org.apache.hadoop.hdfs.server.datanode.DataNode.makeInstance(DataNode.java:1582) > at > org.apache.hadoop.hdfs.server.datanode.DataNode.instantiateDataNode(DataNode.java:1521) > at > org.apache.hadoop.hdfs.server.datanode.DataNode.createDataNode(DataNode.java:1539) > at > org.apache.hadoop.hdfs.server.datanode.DataNode.secureMain(DataNode.java:1665) > at > org.apache.hadoop.hdfs.server.datanode.DataNode.main(DataNode.java:1682) > > Please help me on this issue. > > Thanks, > Prabhu. > -- Thanks & Regards, Anil Gupta
