New function in maintenance level upgrades (On platforms other than z/OS® )

IBM® might introduce new functions between releases in maintenance level upgrades such as fix packs. A maintenance level upgrade including new function increases the maximum command level of an installation.

When you apply the maintenance level upgrade, the installation supports the new command level. A queue manager associated with the installation is not able to use the new function until you have run strmqm to set the queue manager to the new command level.

A fix pack introducing a new function also includes regular fixes as a normal fix pack. If you do not want to use the function, but apply the fixes, do not enable the new function for any queue manager. The fix pack then is a fully reversible maintenance level upgrade. If you want to use a new function with a queue manager, you must change the command level of the queue manager. If one queue manager associated with an installation enables the new function, the fix pack introducing the new function and all previous fix packs cannot be removed anymore.

By applying a maintenance level upgrade that introduces a new function the IBM MQ installation supports an additional command level. An installation can therefore support multiple command levels and multiple queue managers associated with it can run on different command levels.

To enable a new function for a queue manager, you must set the command level of queue manager to the command level supporting the new function. Because command levels are cumulative, the command level also supports all other functions introduced by previous maintenance level upgrades. By enabling a new function from a maintenance level upgrade you therefore enable all new functions from previous maintenance level upgrades, too.

Example

You have installed two fix packs including new functions:

  1. Fix pack 7.1.0.2, introducing the command level 711.
  2. Fix pack 7.1.0.15, introducing the command level 712.

You might have also installed other fix packs, but these did not introduce new function.

You want to use the new function from fix pack 7.1.0.15 on one of your queue managers. You enable command level 712 for that queue manager using the strmqm command. This enables all of the function introduced in both fix packs. It is not possible to use the function introduced by command level 712 without also enabling the function introduced by command level 711.

Once you have enabled command level 712 for a queue manager, the minimum version of product code to start the queue manager is 7.1.0.15. If you uninstall fix pack 7.1.0.15 from the installation with which the queue manager is associated, you will not be able to start the queue manager. In this situation, the strmqm command fails and issues error message AMQ7204 indicating that the queue manager has already been started by a newer release. If you have multiple installations of IBM MQ, you can start the queue manager using another installation which satisfies this minimum version requirement.