[ZOOKEEPER-919] Ephemeral nodes remains in one of ensemble after deliberate SIGKILL

• Type: Bug
• Status: Closed
• Priority: Blocker
• Resolution: Duplicate
• Affects Version/s: 3.3.1
• Fix Version/s: 3.3.3, 3.4.0
• Component/s: server

Environment

Linux CentOS 5.3 64bit, JDK 1.6.0-22
SLES 11

• Assignee: Unassigned
• Reporter: Chang Song
• Created: 04/Nov/10 13:43
• Updated: 23/Nov/11 19:22
• Resolved: 19/Nov/11 01:11

Description

I was testing stability of Zookeeper ensemble for production deployment. Three node ensemble cluster configuration.
In a loop, I kill/restart three Zookeeper clients that created one ephemeral node each, and at the same time,
I killed Java process on one of ensemble (dont' know if it was a leader or not). Then I restarted Zookeeper on the server,

It turns out that on two zookeeper ensemble servers, all the ephemeral nodes are gone (it should), but on the newly started
Zookeeper server, the two old ephemeral nodes stayed. The zookeeper didn't restart in standalone mode since new ephemeral
nodes gets created on all ensemble servers.
I captured the log.

2010-11-04 17:48:50,201 - INFO [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:17288:NIOServerCnxn$Factory@250] - Accepted socket connection from /10.25.131.21:11191
2010-11-04 17:48:50,202 - INFO [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:17288:NIOServerCnxn@776] - Client attempting to establish new session at /10.25.131.21:11191
2010-11-04 17:48:50,203 - INFO [CommitProcessor:1:NIOServerCnxn@1579] - Established session 0x12c160c31fc000b with negotiated timeout 30000 for client /10.25.131.21:11191
2010-11-04 17:48:50,206 - WARN [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:17288:NIOServerCnxn@633] - EndOfStreamException: Unable to read additional data from client sessionid 0x12c160c31fc000b, likely client has closed socket
2010-11-04 17:48:50,207 - INFO [NIOServerCxn.Factory:0.0.0.0/0.0.0.0:17288:NIOServerCnxn@1434] - Closed socket connection for client /10.25.131.21:11191 which had sessionid 0x12c160c31fc000b
2010-11-04 17:48:50,207 - ERROR [CommitProcessor:1:NIOServerCnxn@444] - Unexpected Exception:
java.nio.channels.CancelledKeyException
at sun.nio.ch.SelectionKeyImpl.ensureValid(SelectionKeyImpl.java:55)
at sun.nio.ch.SelectionKeyImpl.interestOps(SelectionKeyImpl.java:59)
at org.apache.zookeeper.server.NIOServerCnxn.sendBuffer(NIOServerCnxn.java:417)
at org.apache.zookeeper.server.NIOServerCnxn.sendResponse(NIOServerCnxn.java:1508)
at org.apache.zookeeper.server.FinalRequestProcessor.processRequest(FinalRequestProcessor.java:367)
at org.apache.zookeeper.server.quorum.CommitProcessor.run(CommitProcessor.java:73)

Issue Links

• relates to: ZOOKEEPER-962 leader/follower coherence issue when follower is receiving a DIFF