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https://issues.apache.org/jira/browse/KAFKA-2143?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15242412#comment-15242412
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Jason Rosenberg commented on KAFKA-2143:
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Hello, I recently experienced this issue, as described in the original 
description above.  We are running 0.8.2.2.
Note, in the original description above (and in my case as well), there was no 
evidence of a network glitch, and no evidence of any partition leadership 
change.  So, I'm concerned whether the discussion that follows in this ticket 
(which describes network glitches and leadership changes almost exclusively) 
really addressed the original issue as reported (and my recent observation of 
this as well).

Can someone comment on this please?  [~becket_qin]

> Replicas get ahead of leader and fail
> -------------------------------------
>
>                 Key: KAFKA-2143
>                 URL: https://issues.apache.org/jira/browse/KAFKA-2143
>             Project: Kafka
>          Issue Type: Bug
>          Components: replication
>    Affects Versions: 0.8.2.1
>            Reporter: Evan Huus
>            Assignee: Jiangjie Qin
>             Fix For: 0.9.0.1
>
>
> On a cluster of 6 nodes, we recently saw a case where a single 
> under-replicated partition suddenly appeared, replication lag spiked, and 
> network IO spiked. The cluster appeared to recover eventually on its own,
> Looking at the logs, the thing which failed was partition 7 of the topic 
> {{background_queue}}. It had an ISR of 1,4,3 and its leader at the time was 
> 3. Here are the interesting log lines:
> On node 3 (the leader):
> {noformat}
> [2015-04-23 16:50:05,879] ERROR [Replica Manager on Broker 3]: Error when 
> processing fetch request for partition [background_queue,7] offset 3722949957 
> from follower with correlation id 148185816. Possible cause: Request for 
> offset 3722949957 but we only have log segments in the range 3648049863 to 
> 3722949955. (kafka.server.ReplicaManager)
> [2015-04-23 16:50:05,879] ERROR [Replica Manager on Broker 3]: Error when 
> processing fetch request for partition [background_queue,7] offset 3722949957 
> from follower with correlation id 156007054. Possible cause: Request for 
> offset 3722949957 but we only have log segments in the range 3648049863 to 
> 3722949955. (kafka.server.ReplicaManager)
> [2015-04-23 16:50:13,960] INFO Partition [background_queue,7] on broker 3: 
> Shrinking ISR for partition [background_queue,7] from 1,4,3 to 3 
> (kafka.cluster.Partition)
> {noformat}
> Note that both replicas suddenly asked for an offset *ahead* of the available 
> offsets.
> And on nodes 1 and 4 (the replicas) many occurrences of the following:
> {noformat}
> [2015-04-23 16:50:05,935] INFO Scheduling log segment 3648049863 for log 
> background_queue-7 for deletion. (kafka.log.Log) (edited)
> {noformat}
> Based on my reading, this looks like the replicas somehow got *ahead* of the 
> leader, asked for an invalid offset, got confused, and re-replicated the 
> entire topic from scratch to recover (this matches our network graphs, which 
> show 3 sending a bunch of data to 1 and 4).
> Taking a stab in the dark at the cause, there appears to be a race condition 
> where replicas can receive a new offset before the leader has committed it 
> and is ready to replicate?



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