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https://issues.apache.org/jira/browse/HBASE-3362?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12974513#action_12974513
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Hudson commented on HBASE-3362:
-------------------------------
Integrated in HBase-TRUNK #1697 (See
[https://hudson.apache.org/hudson/job/HBase-TRUNK/1697/])
> If .META. offline between OPENING and OPENED, then wrong server location in
> .META. is possible
> ----------------------------------------------------------------------------------------------
>
> Key: HBASE-3362
> URL: https://issues.apache.org/jira/browse/HBASE-3362
> Project: HBase
> Issue Type: Bug
> Reporter: stack
> Assignee: stack
> Priority: Critical
> Fix For: 0.90.0
>
>
> This is a good one. It happened to me testing OOME in split logging.
> * Balancer moves region to new location, regionservrer X.
> * New location regionserver X successfully opens the region and then goes to
> update .META.
> * At this point, the server carrying .META. crashes.
> * Regionserver X is stuck waiting on .META. to come back online. It takes so
> long master times out the region-in-transition
> * Master assigns the region elsewhere to regionserver Y
> * It opens successfully on regionserver Y and then it also parks waiting on
> .META. coming online
> * .META. comes online
> * The two servers X and Y race to update .META.
> I saw case where server X edit went in after server Ys edit which means that
> lookups in .META. get the wrong server. HBCK can detect this situation.
> RegionServer X when it wakes up coreeclty notices that its lost control of
> the region but the damage is done -- where damage is .META. edit.
> Chatting with Jon, he suggested that regionserver X should 'rollback' the
> .META. edit -- do explicit delete of what it added. This would work I think
> but chatting more, I'll make a fix that keeps updating the zookeeper OPENING
> state while edit goes on in a separate thread. Our continuous setting of
> OPENING will make it so region-in-transition does not timeout.
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