[
https://issues.apache.org/jira/browse/HDFS-4238?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13506674#comment-13506674
]
Todd Lipcon commented on HDFS-4238:
-----------------------------------
Hi Vinay. I agree it's a bug if the SBN is purging edits from the shared
storage. However, I don't follow the scenario you mentioned:
bq. >> After some time Active NN is restarted and StandBy NN switched to Active.
bq. Now current Standby not able to load any edits from shared storage, as
expected edits are not present in shared storage. Its keep running idle.
By "current Standby", do you mean the one that was Active prior to the restart?
Just to clarify, there was no permanent data loss here - just that you had to
manually copy one of the checkpoints from the new Active over to the new
Standby, and restart the new Standby before you could resynchronize?
> [HA] Standby namenode should not do purging of shared storage edits.
> --------------------------------------------------------------------
>
> Key: HDFS-4238
> URL: https://issues.apache.org/jira/browse/HDFS-4238
> Project: Hadoop HDFS
> Issue Type: Bug
> Components: ha
> Affects Versions: 3.0.0, 2.0.2-alpha
> Reporter: Vinay
>
> This happened in our cluster,
> >> Standby NN was keep doing checkpoint every one hour and uploading to
> >> Active NN was continuously failing due to some kerberos issue and nobody
> >> noticed this, since Active was servicing properly.
> >> Active NN was up for long time with fsimage having very least transaction.
> >> Standby NN has saved the checkpoint in its name dir and purged the txns >
> >> 1000000 from shared storage ( includes edits which are not present in
> >> Active NN's fsimage)
> >> After some time Active NN is restarted and StandBy NN switched to Active.
> Now current Standby not able to load any edits from shared storage, as
> expected edits are not present in shared storage. Its keep running idle.
> So {{editLog.purgeLogsOlderThan(purgeLogsFrom);}} always should be called
> from Active NameNode.
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
