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It should be highlighted in the documentation that this newly introduced property is not compatible with anything else but the DefaultReplicationPolicy

This solution was rejected in the KIP-690 as an alternative

The scope of this change is smaller than the KIP-690, as it only wants to make the heartbeats topic name configurable.
The configuration of the mirror maker is not straight forward with all that options. However, most of those properties are hidden from the user with a reasonable default value, so in my opinion it should not confuse the users, but it is there if someone want to modify it.
Renaming an internal topic should not require implementing a new replication policy class and attaching it to the classpath in my opinion.

Rejected Alternatives

• Divert from the DefaultReplicationPolicy and use a custom one.

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