Multiple queue manager versions in z/OS

There can be several WebSphere MQ subsystems in a z/OS image, and they can use different versions of WebSphere MQ, provided the WebSphere MQ early code modules are of the latest version being used. (These modules are loaded at z/OS IPL time and are shared among all the WebSphere MQ subsystems in the z/OS image.)

This means that we can run one queue manager with V6 and another in the same image with an earlier version, provided that the early code is that of V6.

Use STEPLIBs to control which level of WebSphere MQ is used.