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• Behavior with mixed rack configurations
• Behavior with classic and new protocol groups
  

If there are alternative ways of accomplishing the same thing, what were they? The purpose of this section is to motivate why the design is the way it is and not some other way.

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Rejected Alternatives

Alternative 1: Create a New API
Proposal: Create describeConsumerGroupsWithRack() method
Rejection Reason:

• Unnecessary API proliferation
• The information already exists in the protocol
• Extending existing API is more intuitive
• Similar precedent: KIP-345 added groupInstanceId to existing MemberDescription