[KAFKA-10332] MirrorMaker2 fails to detect topic if remote topic is created first

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.6.0
• Fix Version/s: 2.7.0, 2.5.2, 2.6.1
• Component/s: mirrormaker
• Assignee: Mickael Maison
• Reporter: Mickael Maison
• Reviewer: Randall Hauch
• Created: 31/Jul/20 09:05
• Updated: 19/Oct/20 17:28
• Resolved: 19/Oct/20 17:28

Description

Setup:

• 2 clusters: source and target
• Mirroring data from source to target
• create a topic called source.mytopic on the target cluster
• create a topic called mytopic on the source cluster
  At this point, MM2 does not start mirroring the topic.

This also happens if you delete and recreate a topic that is being mirrored.

The issue is in refreshTopicPartitions() which basically does a diff between the 2 clusters.
When creating the topic on the source cluster last, it makes the partition list of both clusters match, hence not triggering a reconfiguration

Issue Links

• links to: GitHub Pull Request #9343