Applying maintenance to IBM MQ
Maintenance is the application of a reversible fix. Any changes to queue manager data are compatible with the previous code level.
About this task
Long Term Support releases- On Multiplatforms, if your enterprise is using the Long Term Support (LTS) release model, maintenance is the process of applying interim fixes or fix packs.
Continuous Delivery releases- On all supported platforms, if your enterprise is using the Continuous Delivery (CD) release model, you also keep up-to-date by routinely applying the latest CD release.
For more information about Long Term Support and Continuous Delivery releases, see IBM MQ Release Types.
An important characteristic of applying maintenance is that it must be reversible. Reversibility implies two things:
- The previous level of code is fully restored.
- Changes that are made to IBM MQ objects are compatible. Changes are things like the creation or deletion of persistent messages, changes to queue managers, channels, topics, and queues. New and modified objects continue to work correctly with the restored level of code.
The reversibility of a maintenance package limits the extent of functional changes that are included in a maintenance package. No irreversible changes are included in a maintenance package. But, reversibility has limits. A maintenance package might include new programming and administrative interfaces. If you build new or modified applications to use the new interfaces, those applications do not work, if the maintenance package is removed.
On a smaller scale, a fix pack or interim fix might introduce a new configuration parameter to solve a problem. If you remove the fix pack or interim fix, although the new interface introduced by the change is not available any more, IBM MQ works with any objects that have been changed by the configuration parameter. For example, a new Java system property might introduce a parameter to set a code page for queue manager data conversion. The fix does not change any existing persistent queue manager state information. It can be removed, and the queue manager continues to work as before, but without the capability introduced in the fix.
On different platforms, you employ different mechanisms to install and maintain software releases. Installing a release at a new maintenance level, and applying maintenance level updates to update an earlier release to the same maintenance level, have different results.
When you update the maintenance or fix level of IBM MQ by applying a regular maintenance level update, we can reverse the update by removing the fix. When you update the maintenance or fix level of IBM MQ by applying a maintenance level update containing a new function, we can reverse that update and all previously reversible updates until a queue manager associated with the installation enables the new function.
Maintenance levels and fix levels are both supplied from the service site, Fix Central. For direct links to specific fix packs and other IBM MQ resources on Fix Central, go to Downloading IBM MQ Version 9.1 and select the tab for the IBM MQ version that you require. Fix Central has a function to tell you what updates we can apply to the current level of our system.
Procedure
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For information on how to apply and remove fix packs on Multiplatforms, see the appropriate link, or links, for the
platform or platforms your enterprise uses, in the following table.
Apply Remove AIX AIX Linux Linux IBM i IBM i Windows Windows - For z/OS, see Applying and removing maintenance on z/OS.
- Querying the maintenance level
- Applying and removing maintenance on Windows
- Applying and removing maintenance on UNIX and Linux
- Applying and removing maintenance on IBM i
- Applying and removing maintenance on z/OS
Parent topic: Maintain and migrate IBM MQ
Related concepts
- The version naming scheme for IBM MQ for Multiplatforms
- Multi-installation queue manager coexistence on UNIX, Linux, and Windows
- Queue manager coexistence
Related information