[KAFKA-13465] when auto create topics enable,server create inner topic of MirrorMaker unexpectedly

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 2.7.0, 2.8.0, 2.7.1, 3.0.0
• Component/s: mirrormaker
• Assignee: Unassigned
• Reporter: ZhenChun Pan
• Created: 19/Nov/21 03:47
• Updated: 24/Nov/21 03:34

Description

Hi Team

Mirror Maker: 2.7.0

when i enable auto create topic in both side: 

auto.create.topics.enable=true

 

sometimes，mirror maker inner topic create by server not expected，mirror naker start error.

```

[2021-11-19 18:03:56,707] ERROR [Worker clientId=connect-2, groupId=pr-mm2] Uncaught exception in herder work thread, exiting: (org.apache.kafka.connect.runtime.distributed.DistributedHerder)
org.apache.kafka.common.config.ConfigException: Topic 'mm2-configs.pr.internal' supplied via the 'config.storage.topic' property is required to have 'cleanup.policy=compact' to guarantee consistenc***{}##****connector configurations, but found the topic currently has 'cleanup.policy=delete'. Continuing would likely result in eventually losing connector configurations and problems restarting this Connect cluster in the future. Change the 'config.storage.topic' property in the Connect worker configurations to use a topic with 'cleanup.policy=compact'.
at org.apache.kafka.connect.util.TopicAdmin.verifyTopicCleanupPolicyOnlyCompact(TopicAdmin.java:420)
at org.apache.kafka.connect.storage.KafkaConfigBackingStore$1.run(KafkaConfigBackingStore.java:501)
at org.apache.kafka.connect.util.KafkaBasedLog.start(KafkaBasedLog.java:133)
at org.apache.kafka.connect.storage.KafkaConfigBackingStore.start(KafkaConfigBackingStore.java:268)
at org.apache.kafka.connect.runtime.AbstractHerder.startServices(AbstractHerder.java:130)
at org.apache.kafka.connect.runtime.distributed.DistributedHerder.run(DistributedHerder.java:288)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)

```

I think the solution is to exclude mirror maker innner topic when auto creating topics. (AutoTopicCreationManager.scala)

With this change, this problem already resolve for me.