[HBASE-13935] Orphaned namespace table ZK node should not prevent master to start

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.0.0, 0.98.13
• Fix Version/s: 0.98.14, 1.0.2, 1.2.0, 1.1.1, 1.3.0
• Component/s: master
• Hadoop Flags: Reviewed
• Assignee: Stephen Yuan Jiang
• Reporter: Stephen Yuan Jiang
• Created: 18/Jun/15 17:43
• Updated: 31/Aug/15 22:39
• Resolved: 21/Jun/15 06:13

Description

Before we have the state-of-art Procedure V2 feature (HBASE 1.0 release or older), we frequently see the following issue (orphaned ZK node) that prevent master to start (at least in testing):

2015-06-16 17:54:36,472 FATAL [master:10.0.0.99:60000] master.HMaster: Unhandled exception. Starting shutdown.
org.apache.hadoop.hbase.TableExistsException: hbase:namespace
	at org.apache.hadoop.hbase.master.handler.CreateTableHandler.prepare(CreateTableHandler.java:137)
	at org.apache.hadoop.hbase.master.TableNamespaceManager.createNamespaceTable(TableNamespaceManager.java:232)
	at org.apache.hadoop.hbase.master.TableNamespaceManager.start(TableNamespaceManager.java:86)
	at org.apache.hadoop.hbase.master.HMaster.initNamespace(HMaster.java:1123)
	at org.apache.hadoop.hbase.master.HMaster.finishInitialization(HMaster.java:947)
	at org.apache.hadoop.hbase.master.HMaster.run(HMaster.java:618)
	at java.lang.Thread.run(Thread.java:745)
2015-06-16 17:54:36,472 INFO  [master:10.0.0.99:60000] master.HMaster: Aborting

The above call trace is from a 0.98.x test run. We saw similar issue in 1.0.x run, too.

The proposed fix is to ignore the zk node and force namespace table creation to be complete so that master can start successfully.