[Hadoop-common-user] Cannot lock storage, directory is already locked

Hi guys,

I'm using an NFS cluster consisting of 30 machines, but only specified 3 of
the nodes to be my hadoop cluster. So my problem is this. Datanode won't
start in one of the nodes because of the following error:

org.apache.hadoop.hdfs.server.common.Storage: Cannot lock storage
/cs/student/mark/tmp/hodhod/dfs/data. The directory is already locked

I think it's because of the NFS property which allows one node to lock it
then the second node can't lock it. Any ideas on how to solve this error?

Thanks,
Mark