A cluster membership is an IBM MQ object consisting of logically associated queue managers. In a cluster membership, the queue managers can make the queues that they host available to other queue managers in the cluster without the need for explicit channel definitions, remote-queue definitions, or transmission queues for each destination. Every queue manager in a cluster can transmit messages to any other queue manager located in the same cluster. This is done via a single transmission queue (each cluster queue manager has one). Refer to the IBM Knowledge Center for more information on cluster memberships.
When new cluster memberships are created, repositories are automatically generated using the new cluster name. They are created on the queue managers that will hold the full repositories. Receiver channels are automatically defined for new cluster memberships, as well as sender channels to the full repository.
Learn more about clusters in the following articles: