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https://issues.apache.org/jira/browse/HBASE-21844?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16762923#comment-16762923
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Bahram Chehrazy commented on HBASE-21844:
-----------------------------------------
[~sershe], that's right. This situation looks like HBASE-21788. Let's continue
conversation about this issue there.
@[~Apache9], I meant, when the meta server goes down, the ServerManager fails
to update the znode with the state of meta (see the first if stmt in
MetaTableLocator.setMetaLocation). The znode will only be updated when the SCP
succeeds. In that case, the meta state goes from OPEN to OPENING and then back
to OPEN. And if something goes wrong and the master restart, master finds meta
in OPEN state based on the znode state. We need to be sure znode state gets
updated as soon as the meta server dies.
> 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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