Migrating to alter or partition queue files

You can use runnsncf MIGRATE commands to alter the attributes of a queue file or partition a queue file.

On IBM® MQ for HPE NonStop V8.1, queues are represented by Enscribe key sequenced files. For each queue there is exactly one file representing the queue and containing persistent messages.

You might need to change attributes of a queue file. If, for example, a disk is too busy, you might want to move a heavily-used queue file to a different disk. Because of disk space shortage or performance issues, you might also want to use partitioned queue files. Moving existing queue files to a different volume, partitioning, or de-partitioning existing queue files is called “queue file migration”. Queue file migration can be done while the queue manager is up and running and the queue is in use (online migration) or while the queue manager is stopped (offline migration). The migration is controlled either by runnscnf or, as an alternative, by altmqfls (if only one single queue is to be migrated).

Queue file migration creates a new physical file for the queue, and copies the data from the old file to the new file.