In stress testing failover, I had the following failure:
- NN1 rolls edit logs and starts writing edits_inprogress_1000
- NN1 crashes before writing the START_LOG_SEGMENT transaction
- NN2 tries to become active, and calls recoverUnfinalizedSegment. Since the log file contains no valid transactions, it is marked as corrupt and renamed with the .corrupt suffix
- The sanity check in openLogsForWrite will refuse to open a new in-progress log at the same txid. Failover does not proceed.