[
https://issues.apache.org/jira/browse/HBASE-9888?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16555225#comment-16555225
]
Pankaj Kumar commented on HBASE-9888:
-------------------------------------
Reattached 002 patch for QA run.
> HBase replicates edits written before the replication peer is created
> ---------------------------------------------------------------------
>
> Key: HBASE-9888
> URL: https://issues.apache.org/jira/browse/HBASE-9888
> Project: HBase
> Issue Type: Bug
> Affects Versions: 1.5.0
> Reporter: Dave Latham
> Priority: Major
> Attachments: HBASE-9888.branch-1.001.patch,
> HBASE-9888.branch-1.002.patch
>
>
> When creating a new replication peer the ReplicationSourceManager enqueues
> the currently open HLog to the ReplicationSource to ship to the destination
> cluster. The ReplicationSource starts at the beginning of the HLog and ships
> over any pre-existing writes.
> A workaround is to roll all the HLogs before enabling replication.
> A little background for how it affected us - we were migrating one cluster in
> a master-master pair. I.e. transitioning from A <\-> B to B <-> C. After
> shutting down writes from A -> B we enabled writes from C -> B. However,
> this replicated some earlier writes that were in C's HLogs that had
> originated in A. Since we were running a version of HBase before HBASE-7709
> those writes then got caught in a infinite replication cycle and bringing
> down region servers OOM because of HBASE-9865.
> However, in general, if one wants to manage what data gets replicated, one
> wouldn't expect that potentially very old writes would be included when
> setting up a new replication link.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
