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Queue-sharing groups
Queue-sharing groups exist only on z/OS® queue managers. A queue-sharing group is a group of queue managers that can access the same shared queues. Each member of the queue-sharing group has access to the same set of shared queues.
All the queue-sharing groups to which the queue managers in IBM® MQ Explorer belong are shown in the Queue Sharing Group folder. All the resources that members of a queue-sharing group can access are shown in folders in the queue-sharing group.
Queue-sharing groups have a name of up to four characters. The name must be unique in your network, and must be different from any queue manager names.
You cannot create or configure queue-sharing groups in IBM MQ Explorer.
For more information, see Queue sharing groups and clusters in the IBM MQ online product documentation.
Group definitions
Group definitions is the collective term for IBM MQ objects that are defined on queue managers in a queue-sharing group and have the queue-sharing group disposition of Group. Any IBM MQ object that can be defined on a z/OS queue manager can have the queue-sharing group disposition of Group. When you create a group definition object, the definition of the object is stored in the shared repository on Db2.
IBM MQ automatically creates a copy of the object (with queue-sharing group disposition Copy) for each queue manager and stores it on the queue manager's page set zero with the queue manager's private objects, which have disposition Private. A page set is a data set that is specially formatted for use by IBM MQ. The messages on queues that have disposition Copy are also stored on page sets but they should not be stored on page set zero because if page set zero gets full, IBM MQ cannot function correctly. You can specify which page set the messages are stored on by creating one or more storage class objects which map the queues to page sets.
All of the group definitions that belong to a queue manager are shown in the queue manager's folder. All of the group definitions in a queue-sharing group are also shown in the queue-sharing group's Group Definitions folder.