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https://issues.apache.org/jira/browse/FLINK-11654?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16788250#comment-16788250
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Dawid Wysakowicz commented on FLINK-11654:
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The workaround is to set different uids
https://ci.apache.org/projects/flink/flink-docs-release-1.7/ops/state/savepoints.html#assigning-operator-ids
for the kafka producers.
I would be against introducing additional configuration parameter. This would
introduce additional complexity not just in case of code, but also it would
introduce additional corner cases while restoring state for an operator. What
should happen in a user tries to restore state after changing the
{{TransactionIdSeed}}. I think the operator id can serve this use cases very
well. I agree though we should improve documentation around this topic.
> Multiple transactional KafkaProducers writing to same cluster have clashing
> transaction IDs
> -------------------------------------------------------------------------------------------
>
> Key: FLINK-11654
> URL: https://issues.apache.org/jira/browse/FLINK-11654
> Project: Flink
> Issue Type: Bug
> Components: Connectors / Kafka
> Affects Versions: 1.7.1
> Reporter: Jürgen Kreileder
> Priority: Major
> Fix For: 1.9.0
>
>
> We run multiple jobs on a cluster which write a lot to the same Kafka topic
> from identically named sinks. When EXACTLY_ONCE semantic is enabled for the
> KafkaProducers we run into a lot of ProducerFencedExceptions and all jobs go
> into a restart cycle.
> Example exception from the Kafka log:
>
> {code:java}
> [2019-02-18 18:05:28,485] ERROR [ReplicaManager broker=1] Error processing
> append operation on partition finding-commands-dev-1-0
> (kafka.server.ReplicaManager)
> org.apache.kafka.common.errors.ProducerFencedException: Producer's epoch is
> no longer valid. There is probably another producer with a newer epoch. 483
> (request epoch), 484 (server epoch)
> {code}
> The reason for this is the way FlinkKafkaProducer initializes the
> TransactionalIdsGenerator:
> The IDs are only guaranteed to be unique for a single Job. But they can clash
> between different Jobs (and Clusters).
>
>
> {code:java}
> ---
> a/flink-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/FlinkKafkaProducer.java
> +++
> b/flink-connectors/flink-connector-kafka/src/main/java/org/apache/flink/streaming/connectors/kafka/FlinkKafkaProducer.java
> @@ -819,6 +819,7 @@ public class FlinkKafkaProducer<IN>
> nextTransactionalIdHintState =
> context.getOperatorStateStore().getUnionListState(
> NEXT_TRANSACTIONAL_ID_HINT_DESCRIPTOR);
> transactionalIdsGenerator = new TransactionalIdsGenerator(
> + // the prefix probably should include job id and maybe cluster id
> getRuntimeContext().getTaskName() + "-" +
> ((StreamingRuntimeContext) getRuntimeContext()).getOperatorUniqueID(),
> getRuntimeContext().getIndexOfThisSubtask(),
>
> getRuntimeContext().getNumberOfParallelSubtasks(),{code}
>
>
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