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https://issues.apache.org/jira/browse/KAFKA-10357?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17174986#comment-17174986
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Sophie Blee-Goldman commented on KAFKA-10357:
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How are we going to handle restarts/upgrades/etc? The only way to distinguish
between a "first-ever" rebalance and the rebalance following a restart is to
persist that information, otherwise a member who gets bounced and rejoins will
assume it's the very first rebalance.
We could augment the subscription protocol but even that wouldn't be safe for a
non-rolling upgrade. If every member is stopped and restarted, they'll all lose
knowledge of their past lives and everyone will assume it's the first
rebalance. Maybe that's no so bad and we can just warn people not to delete
all their topics when they do a full restart. (Of course if warning people was
sufficient then we wouldn't be having this conversation in the first place..)
> Handle accidental deletion of repartition-topics as exceptional failure
> -----------------------------------------------------------------------
>
> Key: KAFKA-10357
> URL: https://issues.apache.org/jira/browse/KAFKA-10357
> Project: Kafka
> Issue Type: Improvement
> Components: streams
> Reporter: Guozhang Wang
> Assignee: Bruno Cadonna
> Priority: Major
>
> Repartition topics are both written by Stream's producer and read by Stream's
> consumer, so when they are accidentally deleted both clients may be notified.
> But in practice the consumer would react to it much quicker than producer
> since the latter has a delivery timeout expiration period (see
> https://issues.apache.org/jira/browse/KAFKA-10356). When consumer reacts to
> it, it will re-join the group since metadata changed and during the triggered
> rebalance it would auto-recreate the topic silently and continue, causing
> data lost silently.
> One idea, is to only create all repartition topics *once* in the first
> rebalance and not auto-create them any more in future rebalances, instead it
> would be treated similar as INCOMPLETE_SOURCE_TOPIC_METADATA error code
> (https://issues.apache.org/jira/browse/KAFKA-10355).
> The challenge part would be, how to determine if it is the first-ever
> rebalance, and there are several wild ideas I'd like to throw out here:
> 1) change the thread state transition diagram so that CREATED state would not
> transit to PARTITION_REVOKED but only to PARTITION_ASSIGNED, then in the
> assign function we can check if the state is still in CREATED and not RUNNING.
> 2) augment the subscriptionInfo to encode whether or not this is the first
> time ever rebalance.
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