[HADOOP-11722] Some Instances of Services using ZKDelegationTokenSecretManager go down when old token cannot be deleted

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.6.0
• Fix Version/s: 2.7.0
• Target Version/s: 2.7.0
• Hadoop Flags: Reviewed
• Assignee: Arun Suresh
• Reporter: Arun Suresh
• Created: 16/Mar/15 21:39
• Updated: 23/Mar/20 18:55
• Resolved: 18/Mar/15 02:43

Description

The delete node code in ZKDelegationTokenSecretManager is as follows :

       while(zkClient.checkExists().forPath(nodeRemovePath) != null){
          zkClient.delete().guaranteed().forPath(nodeRemovePath);
       }

When instances of a Service using ZKDelegationTokenSecretManager try deleting a node simutaneously, It is possible that all of them enter into the while loop in which case, all peers will try to delete the node.. Only 1 will succeed and the rest will throw an exception.. which will bring down the node.

The Exception is as follows :

2015-03-15 10:24:54,000 ERROR org.apache.hadoop.security.token.delegation.AbstractDelegationTokenSecretManager: ExpiredTokenRemover thread received unexpected exception
java.lang.RuntimeException: Could not remove Stored Token ZKDTSMDelegationToken_28
	at org.apache.hadoop.security.token.delegation.ZKDelegationTokenSecretManager.removeStoredToken(ZKDelegationTokenSecretManager.java:770)
	at org.apache.hadoop.security.token.delegation.AbstractDelegationTokenSecretManager.removeExpiredToken(AbstractDelegationTokenSecretManager.java:605)
	at org.apache.hadoop.security.token.delegation.AbstractDelegationTokenSecretManager.access$400(AbstractDelegationTokenSecretManager.java:54)
	at org.apache.hadoop.security.token.delegation.AbstractDelegationTokenSecretManager$ExpiredTokenRemover.run(AbstractDelegationTokenSecretManager.java:656)
	at java.lang.Thread.run(Thread.java:745)
Caused by: org.apache.zookeeper.KeeperException$NoNodeException: KeeperErrorCode = NoNode for /zkdtsm/ZKDTSMRoot/ZKDTSMTokensRoot/DT_28
	at org.apache.zookeeper.KeeperException.create(KeeperException.java:111)
	at org.apache.zookeeper.KeeperException.create(KeeperException.java:51)
	at org.apache.zookeeper.ZooKeeper.delete(ZooKeeper.java:873)
	at org.apache.curator.framework.imps.DeleteBuilderImpl$5.call(DeleteBuilderImpl.java:238)
	at org.apache.curator.framework.imps.DeleteBuilderImpl$5.call(DeleteBuilderImpl.java:233)
	at org.apache.curator.RetryLoop.callWithRetry(RetryLoop.java:107)
	at org.apache.curator.framework.imps.DeleteBuilderImpl.pathInForeground(DeleteBuilderImpl.java:230)
	at org.apache.curator.framework.imps.DeleteBuilderImpl.forPath(DeleteBuilderImpl.java:214)
	at org.apache.curator.framework.imps.DeleteBuilderImpl.forPath(DeleteBuilderImpl.java:41)
	at org.apache.hadoop.security.token.delegation.ZKDelegationTokenSecretManager.removeStoredToken(ZKDelegationTokenSecretManager.java:764)
	... 4 more