Pl check your classpath entries.
Looks like hadoop-core jar before you shutdown the cluster and after u
changed hadoop-env.sh are different
-Sagar
Songting Chen wrote:
Hi,
I modified the classpath in hadoop-env.sh in namenode and datanodes before shutting down the cluster. Then problem appears: I cannot stop hadoop cluster at all. The stop-all.sh shows no datanode/namenode, while all the java processes are running.
So I manually killed the java process. Now the namenode seems to be corrupted and always stays in Safe mode, while the datanodes complain the following weird error:
2008-10-27 17:28:44,141 FATAL org.apache.hadoop.dfs.DataNode: Incompatible
build versions: namenode BV = ; datanode BV = 694836
2008-10-27 17:28:44,244 ERROR org.apache.hadoop.dfs.DataNode:
java.io.IOException: Incompatible build versions: namenode BV = ; datanode BV =
694836
at org.apache.hadoop.dfs.DataNode.handshake(DataNode.java:403)
at org.apache.hadoop.dfs.DataNode.startDataNode(DataNode.java:250)
at org.apache.hadoop.dfs.DataNode.<init>(DataNode.java:190)
at org.apache.hadoop.dfs.DataNode.makeInstance(DataNode.java:2987)
at
org.apache.hadoop.dfs.DataNode.instantiateDataNode(DataNode.java:2942)
at org.apache.hadoop.dfs.DataNode.createDataNode(DataNode.java:2950)
at org.apache.hadoop.dfs.DataNode.main(DataNode.java:3072)
My question is how to recover from such failure. And I guess the correct
practice for changing the CLASSPATH is to shut down the cluster, apply the
change, restart the cluster.
Thanks,
-Songting
