Hi Christian, you should check if the exceptions that you see after the broker is back from maintenance are the same as the ones you posted here. If you are using EXACTLY_ONCE, it could be that the later errors are caused by Kafka purging transactions that Flink attempts to commit [1].
Best, Alexander Fedulov [1] https://nightlies.apache.org/flink/flink-docs-release-1.15/docs/connectors/datastream/kafka/#fault-tolerance On Mon, Jun 13, 2022 at 12:04 PM Martijn Visser <martijnvis...@apache.org> wrote: > Hi Christian, > > I would expect that after the broker comes back up and recovers > completely, these error messages would disappear automagically. It should > not require a restart (only time). Flink doesn't rely on Kafka's > checkpointing mechanism for fault tolerance. > > Best regards, > > Martijn > > Op wo 8 jun. 2022 om 15:49 schreef Christian Lorenz < > christian.lor...@mapp.com>: > >> Hi, >> >> >> >> we have some issues with a job using the flink-sql-connector-kafka (flink >> 1.15.0/standalone cluster). If one broker e.g. is restarted for >> maintainance (replication-factor=2), the taskmanagers executing the job are >> constantly logging errors on each checkpoint creation: >> >> >> >> Failed to commit consumer offsets for checkpoint 50659 >> >> org.apache.flink.kafka.shaded.org.apache.kafka.clients.consumer.RetriableCommitFailedException: >> Offset commit failed with a retriable exception. You should retry >> committing the latest consumed offsets. >> >> Caused by: >> org.apache.flink.kafka.shaded.org.apache.kafka.common.errors.CoordinatorNotAvailableException: >> The coordinator is not available. >> >> >> >> AFAICT the error itself is produced by the underlying kafka consumer. >> Unfortunately this error cannot be reproduced on our test system. >> >> From my understanding this error might occur once, but follow up >> checkpoints / kafka commits should be fine again. >> >> Currently my only way of “fixing” the issue is to restart the >> taskmanagers. >> >> >> >> Is there maybe some kafka consumer setting which would help to circumvent >> this? >> >> >> >> Kind regards, >> >> Christian >> >> Mapp Digital Germany GmbH with registered offices at Dachauer, Str. 63, >> 80335 München. >> Registered with the District Court München HRB 226181 >> Managing Directors: Frasier, Christopher & Warren, Steve >> >> This e-mail is from Mapp Digital and its international legal entities and >> may contain information that is confidential or proprietary. >> If you are not the intended recipient, do not read, copy or distribute >> the e-mail or any attachments. Instead, please notify the sender and delete >> the e-mail and any attachments. >> Please consider the environment before printing. Thank you. >> >
