Can you check what is the value for command 'df -h'in NN machine. I think, one more possibility could be that while saving image itself it would have been currupted.
To avoid such cases it has been already handled in trunk.For more details https://issues.apache.org/jira/browse/HDFS-1594 Regards, Uma ----- Original Message ----- From: "Peng, Wei" <[email protected]> Date: Wednesday, September 21, 2011 9:01 am Subject: java.io.IOException: Incorrect data format To: [email protected] > I was not able to restart my name server because I the name server ran > out of space. Then I adjusted dfs.datanode.du.reserved to 0, and used > tune2fs -m to get some space, but I still could not restart the name > node. > > > > I got the following error: > > java.io.IOException: Incorrect data format. logVersion is -18 but > writables.length is 0. > > > > Anyone knows how to resolve this issue? > > > > Best, > > Wei > > > >
