[KAFKA-9121] Mirror Maker 2.0 doesn't handle the topic names in consumer checkpoints properly when topic name contain separator

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 2.4.0
• Component/s: mirrormaker
• Assignee: Unassigned
• Reporter: Jakub Scholz
• Created: 30/Oct/19 22:00
• Updated: 31/Oct/19 14:39

Description

I was trying the Kafka Mirror Maker 2.0 and run into the following situation:

1) I have 2 Kafka clusters with topic kafka-test-apps topic
2) I configured Mirror Maker with replication.policy.separator=- and with mirroring between cluster a and b.
3) When running Mirror Maker the mirroring of topics works fine. But when I use the RemoteClusterUtils to recover the offsets, the names of the topics for which the offsets are found are a-kafka-test-apps and apps. While the expected topic names would be a-kafka-test-apps and kafka-test-apps.

I tried to find the issue, but didn't found it so far. But it doesn't seem to be in RemoteClusterUtils because the topic names seem to be wrong already in checkpoints.internal topic. So it is probably already processed in the wrong way in the source cluster.

When I use . as the separator, it seems to work fine for me. It looks like the problem is only when the topci names contain already the separator in the original topic name. But using the right separator might not be a solution for this, because you migth have topics with different characters and always have this problem.