Migrating a queue manager in a high-availability configuration
High-availability configurations of queue managers can increase the availability of IBM MQ applications. If a queue manager, or server fails, it is restarted automatically on another server. We can arrange for IBM MQ MQI client applications to automatically reconnect to the queue manager. Server applications can be configured to start when the queue manager starts.
About this task
For IBM MQ for Multiplatforms, high-availability configurations are implemented either by using a high-availability cluster solution or by using multi-instance queue managers. Red Hat Cluster Suite or Microsoft Cluster Service (MSCS) are examples of high-availability cluster solutions.
For IBM MQ for z/OS® there are several alternative techniques to increase queue manager availability; see Availability on z/OS. Migration considerations on z/OS depend on the availability techniques that are employed, and are not described in this topic. The term high-availability configuration refers only to queue managers in configurations on platforms other than z/OS.
The overall principles involved in queue manager migration in a high availability configuration are the same, whether you are migrating a multi-instance queue manager or a high-availability cluster. In either case, the principles are as follows:
- You must not restart a queue manager at a lower command level than the one it was previously running.
- We cannot upgrade the code an active queue manager is running.
- We cannot back up an active queue manager.