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https://issues.apache.org/jira/browse/HBASE-21844?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16761131#comment-16761131
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Bahram Chehrazy commented on HBASE-21844:
-----------------------------------------
We're using an internal version 3.0.4, which is based on 3.0.0. This only
happened a couple times in our environment. In one instance the previous dead
meta server node was removed from the cluster automatically (perhaps due to
maintenance). But the meta znode was never updated. I'm working on another
patch to make sure meta state and its znode gets updated as soon as the
server's ephemera znode expires. That should reduce the chance of getting into
this state. But as [~wchevreuil] mentioned, this could happen in case of
HBASE-21843 or other extreme cases. Having those logs could help debug the
issue.
> Master could get stuck in initializing state while waiting for meta
> -------------------------------------------------------------------
>
> Key: HBASE-21844
> URL: https://issues.apache.org/jira/browse/HBASE-21844
> Project: HBase
> Issue Type: Bug
> Components: master, meta
> Affects Versions: 3.0.0
> Reporter: Bahram Chehrazy
> Assignee: Bahram Chehrazy
> Priority: Major
> Attachments:
> 0001-HBASE-21844-Handling-incorrect-Meta-state-on-Zookeep.patch
>
>
> If the active master crashes after meta server dies, there is a slight chance
> of master getting into a state where the ZK says meta is OPEN, but the server
> is dead and there is no active SCP to recover it (perhaps the SCP has aborted
> and the procWALs were corrupted). In this case the waitForMetaOnline never
> returns.
>
> We've seen this happening a few times when there had been a temporary HDFS
> outage. Following log lines shows this state.
>
> 2019-01-17 18:55:48,497 WARN [master/************:16000:becomeActiveMaster]
> master.HMaster: hbase:meta,,1.1588230740 is NOT online; state=
> {1588230740 *state=*OPEN**, ts=1547780128227,
> server=*************,16020,1547776821322}
> ; *ServerCrashProcedures=false*. Master startup cannot progress, in
> holding-pattern until region onlined.
>
> I'm still investigating why and how to prevent getting into this bad state,
> but nevertheless the master should be able to recover during a restart by
> initiating a new SCP to fix the meta.
>
>
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