[ https://issues.apache.org/jira/browse/HBASE-2413?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
stack resolved HBASE-2413. -------------------------- Hadoop Flags: [Reviewed] Fix Version/s: 0.21.0 Resolution: Fixed Applied branch and trunk. Thanks for the double-review over in http://review.hbase.org/r/36/ Todd. > Master does not respect generation stamps, may result in meta getting > permanently offlined > ------------------------------------------------------------------------------------------ > > Key: HBASE-2413 > URL: https://issues.apache.org/jira/browse/HBASE-2413 > Project: Hadoop HBase > Issue Type: Bug > Components: master > Affects Versions: 0.20.3 > Reporter: Karthik Ranganathan > Assignee: stack > Fix For: 0.20.5, 0.21.0 > > Attachments: 2413-v10.patch, 2413-v4.txt, 2413-v6.patch, > 2413-v7.patch, 2413-v8.patch, 2413-v9.patch, newserver-v3.txt, newserver.txt > > > This happens if the RS is restarted before the zk node expires. The sequence > is as follows: > 1. RS1 dies - lets say its server string was HOST1:PORT1:TS1 > 2. In a few seconds RS1 is restarted, it comes up as HOST1:PORT1:TS2 (TS2 is > more recent than TS1) > 3. Master gets a start up message from RS1 with the server name as > HOST1:PORT1:TS2 > 4. Master adds this as a new RS, tries to red > ---- The master does not use the generation stamps to detect that RS1 has > already restarted. > ---- Also, if RS1 contained meta, master would try to go to HOST1:PORT1:TS1. > It would end up talking to HOST1:PORT1:TS2, which spews a bunch of not > serving region exceptions. > 5. zk node expires for HOST1:PORT1:TS1 > 6. Master tries to process shutdown for HOST1:PORT1:TS1 - this probably > interferes with HOST1:PORT1:TS2 and ends up somehow removing the reassign > meta in the master's queue. > ---- Meta never comes online and master continues logging the following > exception indefinitely: > 2010-04-06 11:02:23,988 DEBUG org.apache.hadoop.hbase.master.HMaster: > Processing todo: ProcessRegionClose of test1,7094000000,1270220428234, false, > reassign: true > 2010-04-06 11:02:23,988 DEBUG > org.apache.hadoop.hbase.master.ProcessRegionClose$1: Exception in > RetryableMetaOperation: > java.lang.NullPointerException > at > org.apache.hadoop.hbase.master.RetryableMetaOperation.doWithRetries(RetryableMetaOperation.java:64) > at > org.apache.hadoop.hbase.master.ProcessRegionClose.process(ProcessRegionClose.java:63) > at > org.apache.hadoop.hbase.master.HMaster.processToDoQueue(HMaster.java:494) > at org.apache.hadoop.hbase.master.HMaster.run(HMaster.java:429) -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.