I have an existing cluster running hadoop-0.20.1, and I am migrating most of the data to a new cluster running -0.20.2. I am seeing this in the namenode logs when I try to run a distcp:
@400000004db263bf29c77134 WARN ipc.Server: Incorrect header or version mismatch from newNN:46111 got version 4 expected version 3 2011-04-23 05:30:55,999 WARN org.apache.hadoop.ipc.Server: Incorrect header or version mismatch from oldNN:48750 got version 3 expected version 4 When I run my distcp, on either side, it dies with a java.io.IOException/java.io.EOFException. Ideas? Am I screwed? I really don't want to drop my new cluster down to 0.20.1. -j
