[jira] [Resolved] (KAFKA-9212) Keep receiving FENCED_LEADER_EPOCH while sending ListOffsetRequest

["Ismael Juma (Jira)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/KAFKA-9212?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Ismael Juma resolved KAFKA-9212.
--------------------------------
    Resolution: Fixed

> Keep receiving FENCED_LEADER_EPOCH while sending ListOffsetRequest
> ------------------------------------------------------------------
>
>                 Key: KAFKA-9212
>                 URL: https://issues.apache.org/jira/browse/KAFKA-9212
>             Project: Kafka
>          Issue Type: Bug
>          Components: consumer, offset manager
>    Affects Versions: 2.3.0, 2.3.1
>         Environment: Linux
>            Reporter: Yannick
>            Assignee: Jason Gustafson
>            Priority: Blocker
>             Fix For: 2.4.0, 2.3.2
>
>
> When running Kafka connect s3 sink connector ( confluent 5.3.0), after one broker got restarted (leaderEpoch updated at this point), the connect worker crashed with the following error : 
> [2019-11-19 16:20:30,097] ERROR [Worker clientId=connect-1, groupId=connect-ls] Uncaught exception in herder work thread, exiting: (org.apache.kafka.connect.runtime.distributed.DistributedHerder:253)
>  org.apache.kafka.common.errors.TimeoutException: Failed to get offsets by times in 30003ms
>  
> After investigation, it seems it's because it got fenced when sending ListOffsetRequest in loop and then got timed out , as follows :
> [2019-11-19 16:20:30,020] DEBUG [Consumer clientId=consumer-3, groupId=connect-ls] Sending ListOffsetRequest (type=ListOffsetRequest, replicaId=-1, partitionTimestamps={connect_ls_config-0={timestamp: -1, maxNumOffsets: 1, currentLeaderEpoch: Optional[1]}}, isolationLevel=READ_UNCOMMITTED) to broker kafka6.fra2.internal:9092 (id: 4 rack: null) (org.apache.kafka.clients.consumer.internals.Fetcher:905)
> [2019-11-19 16:20:30,044] DEBUG [Consumer clientId=consumer-3, groupId=connect-ls] Attempt to fetch offsets for partition connect_ls_config-0 failed due to FENCED_LEADER_EPOCH, retrying. (org.apache.kafka.clients.consumer.internals.Fetcher:985)
>  
> The above happens multiple times until timeout.
>  
> According to the debugs, the consumer always get a leaderEpoch of 1 for this topic when starting up :
>  
>  [2019-11-19 13:27:30,802] DEBUG [Consumer clientId=consumer-3, groupId=connect-ls] Updating last seen epoch from null to 1 for partition connect_ls_config-0 (org.apache.kafka.clients.Metadata:178)
>   
>   
>  But according to our brokers log, the leaderEpoch should be 2, as follows :
>   
>  [2019-11-18 14:19:28,988] INFO [Partition connect_ls_config-0 broker=4] connect_ls_config-0 starts at Leader Epoch 2 from offset 22. Previous Leader Epoch was: 1 (kafka.cluster.Partition)
>   
>   
>  This make impossible to restart the worker as it will always get fenced and then finally timeout.
>   
>  It is also impossible to consume with a 2.3 kafka-console-consumer as follows :
>   
>  kafka-console-consumer --bootstrap-server BOOTSTRAPSERVER:9092 --topic connect_ls_config --from-beginning 
>   
>  the above will just hang forever ( which is not expected cause there is data) and we can see those debug messages :
> [2019-11-19 22:17:59,124] DEBUG [Consumer clientId=consumer-1, groupId=console-consumer-3844] Attempt to fetch offsets for partition connect_ls_config-0 failed due to FENCED_LEADER_EPOCH, retrying. (org.apache.kafka.clients.consumer.internals.Fetcher)
>   
>   
>  Interesting fact, if we do subscribe the same way with kafkacat (1.5.0) we can consume without problem ( must be the way kafkacat is consuming ignoring FENCED_LEADER_EPOCH):
>   
>  kafkacat -b BOOTSTRAPSERVER:9092 -t connect_ls_config -o beginning
>   
>   



--
This message was sent by Atlassian Jira
(v8.3.4#803005)