Queue definition shared by all queue managers

Shared queue definitions are stored in the DB2 database table OBJ_B_QUEUE. Because of this, we need to define the queue only once and then it can be accessed by all the queue managers in the queue-sharing group. This means that there are fewer definitions to make.

By contrast, the definition of a non-shared queue is stored on page set zero of the queue manager that owns the queue (as described in Page sets).

We cannot define a shared queue if a queue with that name has already been defined on the page sets of the defining queue manager. Likewise, you cannot define a local version of a queue on the queue manager page sets if a shared queue with the same name already exists.