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https://issues.apache.org/jira/browse/MESOS-422?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13821711#comment-13821711
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Benjamin Mahler commented on MESOS-422:
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[~wfarner] I prefer that option since it requires no change to what we store in
ZK, we do have this notion in the code (The Group::Membership of the temporary
new leader will not match the leading Group::Membership in ZK), but this
unfortunately gets lost through the current layers of abstraction since the
detection and contending processes were made separate).
> Master leader election should be more robust to stale ephemeral nodes
> ---------------------------------------------------------------------
>
> Key: MESOS-422
> URL: https://issues.apache.org/jira/browse/MESOS-422
> Project: Mesos
> Issue Type: Bug
> Components: master
> Affects Versions: 0.9.0, 0.10.0, 0.11.0, 0.12.0, 0.13.0
> Reporter: Bill Farner
> Assignee: Yan Xu
> Priority: Minor
> Labels: twitter
> Fix For: 0.16.0
>
>
> When a leading master exits abruptly, it may fatefully restart and think it's
> the leader. If particularly unlucky, this could result in a set of masters
> that are indefinitely unstable.
> Sequence of events:
> - Master process becomes leader
> - Master process exits, session expiration counter begins
> - Master process restarts, reads leader node contents, and decides it's the
> leader (based on PID equality)
> - Previous master session expires, node is deleted
> - Master decides a different master is leader, commits suicide
> - Rinse, repeat for newly-created master node
> The salient fact here is that leaders should be concerned with "did i create
> the leader node" (ignoring node data) while clients want to be apprised of
> leader's node data.
> Relevant code:
> https://github.com/apache/mesos/blob/trunk/src/detector/detector.cpp#L548
> ZK leader election recipe, for reference:
> http://zookeeper.apache.org/doc/trunk/recipes.html#sc_leaderElection
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