If possible, you should migrate replicated servers to the same host name and port number. If you must change the host name or port number of a replicated server, all replication agreements that point to that server must be updated manually to point to the new server. For example, if you migrate a consumer server from red.example.com:1389 to blue.example.com:1389, the replication agreements on all masters that point to red.example.com:1389 must be updated manually to point to blue.example.com:1389.
Replication agreements from the migrated master to consumers in the topology are managed by the dsmig migration tool. If your topology does not support automated migration, these replication agreements must also be updated manually.