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Currently with Kafka you cannot have duplicate listeners on the same port. This makes sense when you only have a single IP stack but since we now have both IPv4 and IPv6 there is no reason why you cannot have an IPv4 address and another IPv6 address on the same port.

Note that this change only applies to listeners, advertised listeners already have this feature.

Public Interfaces

• The proposed changes does not require any changes to public interfaces

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