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https://issues.apache.org/jira/browse/FLINK-6006?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15938297#comment-15938297
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Gyula Fora commented on FLINK-6006:
-----------------------------------

I tried restarting the consumer when I was sure that the brokers have 
completely recovered and that still didnt help.

> Kafka Consumer can lose state if queried partition list is incomplete on 
> restore
> --------------------------------------------------------------------------------
>
>                 Key: FLINK-6006
>                 URL: https://issues.apache.org/jira/browse/FLINK-6006
>             Project: Flink
>          Issue Type: Bug
>          Components: Kafka Connector, Streaming Connectors
>            Reporter: Tzu-Li (Gordon) Tai
>            Assignee: Tzu-Li (Gordon) Tai
>            Priority: Blocker
>             Fix For: 1.1.5, 1.2.1
>
>
> In 1.1.x and 1.2.x, the FlinkKafkaConsumer performs partition list querying 
> on restore. Then, only restored state of partitions that exists in the 
> queried list is used to initialize the fetcher's state holders.
> If in any case the returned partition list is incomplete (i.e. missing 
> partitions that existed before, perhaps due to temporary ZK / broker 
> downtime), then the state of the missing partitions is dropped and cannot be 
> recovered anymore.
> In 1.3-SNAPSHOT, this is fixed by changes in FLINK-4280, so only 1.1 and 1.2 
> is affected.
> We can backport some of the behavioural changes there to 1.1 and 1.2. 
> Generally, we should not depend on the current partition list in Kafka when 
> restoring, but just restore all previous state into the fetcher's state 
> holders. 
> This would therefore also require some checking on how the consumer threads / 
> Kafka clients behave when its assigned partitions cannot be reached.



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