HI everyone,
Is there any situation in which creating a new ZK node with the SEQUENCE
flag should result in a "node exists" error? I'm seeing this happening
after a failure of a ZK node that appeared to have been the master; when
the new master takes over, my app is unable to create a new SEQUENCE
node under an existing parent node. I'm using Zookeeper 3.2.2.
Here's a representative log snippet:
--------------------------
3050756 [ProcessThread:-1] TRACE
org.apache.zookeeper.server.PrepRequestProcessor -
:Psessionid:0x12bf518350f0001 type:create cxid:0x4cca0691
zxid:0xfffffffffffffffe txntype:unknown /zkrsm/0000000000000000_record
3050756 [ProcessThread:-1] WARN
org.apache.zookeeper.server.PrepRequestProcessor - Got exception when
processing sessionid:0x12bf518350f0001 type:create cxid:0x4cca0691
zxid:0xfffffffffffffffe txntype:unknown n/a
org.apache.zookeeper.KeeperException$NodeExistsException:
KeeperErrorCode = NodeExists
at
org.apache.zookeeper.server.PrepRequestProcessor.pRequest(PrepRequestProcessor.java:245)
at
org.apache.zookeeper.server.PrepRequestProcessor.run(PrepRequestProcessor.java:114)
3050756 [ProcessThread:-1] DEBUG
org.apache.zookeeper.server.quorum.CommitProcessor - Processing
request:: sessionid:0x12bf518350f0001 type:create cxid:0x4cca0691
zxid:0x50000027e txntype:-1 n/a
3050756 [ProcessThread:-1] DEBUG
org.apache.zookeeper.server.quorum.Leader - Proposing::
sessionid:0x12bf518350f0001 type:create cxid:0x4cca0691 zxid:0x50000027e
txntype:-1 n/a
3050756 [SyncThread:0] TRACE org.apache.zookeeper.server.quorum.Leader
- Ack zxid: 0x50000027e
3050757 [SyncThread:0] TRACE org.apache.zookeeper.server.quorum.Leader
- outstanding proposal: 0x50000027e
3050757 [SyncThread:0] TRACE org.apache.zookeeper.server.quorum.Leader
- outstanding proposals all
3050757 [SyncThread:0] DEBUG org.apache.zookeeper.server.quorum.Leader
- Count for zxid: 0x50000027e is 1
3050757 [FollowerHandler-/172.16.0.28:48776] TRACE
org.apache.zookeeper.server.quorum.Leader - Ack zxid: 0x50000027e
3050757 [FollowerHandler-/172.16.0.28:48776] TRACE
org.apache.zookeeper.server.quorum.Leader - outstanding proposal:
0x50000027e
3050757 [FollowerHandler-/172.16.0.28:48776] TRACE
org.apache.zookeeper.server.quorum.Leader - outstanding proposals all
3050757 [FollowerHandler-/172.16.0.28:48776] DEBUG
org.apache.zookeeper.server.quorum.Leader - Count for zxid: 0x50000027e
is 2
3050757 [FollowerHandler-/172.16.0.28:48776] DEBUG
org.apache.zookeeper.server.quorum.CommitProcessor - Committing
request:: sessionid:0x12bf518350f0001 type:create cxid:0x4cca0691
zxid:0x50000027e txntype:-1 n/a
3050757 [CommitProcessor:0] DEBUG
org.apache.zookeeper.server.FinalRequestProcessor - Processing
request:: sessionid:0x12bf518350f0001 type:create cxid:0x4cca0691
zxid:0x50000027e txntype:-1 n/a
3050757 [CommitProcessor:0] TRACE
org.apache.zookeeper.server.FinalRequestProcessor -
:Esessionid:0x12bf518350f0001 type:create cxid:0x4cca0691
zxid:0x50000027e txntype:-1 n/a
3050757 [FollowerHandler-/172.16.0.28:41062] TRACE
org.apache.zookeeper.server.quorum.Leader - Ack zxid: 0x50000027e
3050757 [FollowerHandler-/172.16.0.28:41062] TRACE
org.apache.zookeeper.server.quorum.Leader - outstanding proposals all
3050757 [FollowerHandler-/172.16.0.28:41062] DEBUG
org.apache.zookeeper.server.quorum.Leader - outstanding is 0
--------------------------
I'm still a n00b at understanding ZK log messages, so maybe there's
something obvious going on. I looked in the JIRA and did my best to
search the mailing list archives, but couldn't find anything related to
this. Any ideas? Thanks very much,
Jeremy
