[HDFS-3771] Namenode can't restart due to corrupt edit logs, timing issue with shutdown and edit log rolling

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Won't Fix
• Affects Version/s: 0.23.3
• Component/s: namenode

Environment

QE, 20 node Federated cluster with 3 NNs and 15 DNs, using Kerberos based security

• Assignee: Unassigned
• Reporter: patrick white
• Created: 07/Aug/12 16:34
• Updated: 02/Apr/13 19:30
• Resolved: 02/Apr/13 19:30

Description

Our 0.23.3 nightly HDFS regression suite encountered a particularly nasty issue recently, which resulted in the cluster's default Namenode being unable to restart, this was on a 20 node Federated cluster with security. The cause appears to be that the NN was just starting to roll its edit log when a shutdown occurred, the shutdown was intentional to restart the cluster as part of an automated test.

The tests that were running do not appear to be the issue in themselves, the cluster was just wrapping up an adminReport subset and this failure case has not reproduce so far, nor was it failing previously. It looks like a chance occurrence of sending the shutdown just as the edit log roll was begun.

From the NN log, the following sequence is noted:

1. an InvalidateBlocks operation had completed
2. FSNamesystem: Roll Edit Log from [Secondary Namenode IPaddr]
3. FSEditLog: Ending log segment 23963
4. FSEditLog: Starting log segment at 23967
4. NameNode: SHUTDOWN_MSG
=> the NN shuts down and then is restarted...
5. FSImageTransactionalStorageInspector: Logs beginning at txid 23967 were are all in-progress
6. FSImageTransactionalStorageInspector: Marking log at /grid/[PATH]/edits_inprogress_0000000000000023967 as corrupt since it has no transactions in it.
7. NameNode: Exception in namenode join [main]java.lang.IllegalStateException: No non-corrupt logs for txid 23967
=> NN start attempts continue to cycle trying to restart but can't, failing on the same exception due to lack of non-corrupt edit logs

If observations are correct and issue is from shutdown happening as edit logs are rolling, does the NN have an equivalent to the conventional fs 'sync' blocking action that should be called, or perhaps has a timing hole?

Issue Links

• relates to: HDFS-2824 HA: failover does not succeed if prior NN died just after creating an edit log segment