Hi. Upgrading from 0.12.3 to 0.13 seems to work fine. (at least the before and after "fsck "and "dfs -lsr" outputs matches).
Then I shut down the DFS cluster, and reformat the DFS (to start a new round of performance test). The datanodes all have the following exception. 2007-06-08 17:13:27,985 ERROR org.apache.hadoop.dfs.DataNode: java.io.IOExceptio n: Incompatible namespaceIDs in /mnt/hadoop/bwolen/dfs/data: namenode namespaceID = 1399119814; datanode namespaceID = -1646824738 I'll blow away these directories and start from scratch. Just thought to let you know. bwolen
