IBM MQ release types and versioning

From IBM® MQ 9.0 there are two types of release; a Long Term Support (LTS) release and Continuous Delivery (CD) release.

LTS and CD release types

The aim of the two release types is to meet the requirement for delivery of new and enhanced IBM MQ functions as rapidly as possible in the next CD release, while at the same time maintaining a stable long term support release for systems that need a long term deployment of IBM MQ, and for customers who prefer this traditional option.

The two release types are distinguishable by the modification number, that is the M digit of the VRMF:

Long Term Support releases have a modification number of zero, for example 9.0.0.
Continuous Delivery releases have a modification number that is non-zero, for example 9.0.1, 9.0.2, and so on.

Each LTS release is supported for the duration of the release. Each CD release is supported for 12 months or while it is one of the most recent two CD releases, whichever is longer. For more information, see IBM MQ FAQ for Long Term Support and Continuous Delivery releases.

To check the IBM MQ version:

Type the command dspmqver, or DSPMQMVER on IBM i. The returned messages include the three-digit VRM or, if maintenance has been applied, the four-digit VRMF.
Use the REST API GET method.
View the queue manager property panel in IBM MQ Explorer.
Look at the CSQY000I message in the queue manager job log. This message is issued when the queue manager starts, and shows the release level and release type.

The command level of a queue manager is the three-digit VRM level. An IBM MQ program can call MQINQ, passing the MQIA_COMMAND_LEVEL selector, to get the command level of the queue manager it is connected to. You can also view the queue manager command level in the queue manager property panel in IBM MQ Explorer.

Maintenance delivery model

From 1Q 2023, there are two types of maintenance:

Fix packs: Fix packs contain roll-ups of all defects fixed since the previous fix pack delivery or GA. Fix packs are produced exclusively for LTS releases during their normal support lifecycle.
Cumulative security updates (CSUs): CSUs are smaller updates and contain security patches released since the previous maintenance or GA. CSUs are produced for LTS releases (including releases in extended support), and for the latest IBM MQ CD release, as required to deliver relevant security patches.

Both types of maintenance are mutually cumulative (that is, they contain everything included in older CSUs and fix packs) and both are installed using the same mechanisms for applying maintenance. Also, both types of maintenance update the F digit of the VRMF to a higher number than any previous maintenance:

For LTS releases, the F digit of the VRMF is either a fix pack number, which is a value divisible by 5, or a CSU number, which is a value not divisible by 5. The final 9.0 fix pack was 9.0.0.13, which predates the new numbering scheme. CSUs continue to be provided, and they follow this numbering scheme. For example, 9.0.0.19 was an LTS CSU, and the next LTS CSU was 9.0.0.21.
For CD releases, the F digit of the VRMF is either a zero or a CSU number, which is a value not divisible by 5. However this does not affect 9.0 CD releases, because they are no longer supported.

For maintenance releases before 1Q 2023, there were no CSU updates. Therefore the F digit in the VRMF always represents the fix pack level.

Maintenance levels do not affect the command level of the queue manager. No migration is required, and maintenance levels do not affect the service end date of a release.

For more information, see Changes to IBM MQ's maintenance delivery model.

For each supported platform, the release type you choose affects ordering, installation, maintenance and migration. For more information, see IBM MQ release types: planning considerations.

Maintenance delivery model: differences by platform

For Multiplatforms, LTS fix packs and CSUs

are downloaded as interim fixes
are downloaded by fix pack or CSU number
are cumulative

For z/OS®, LTS fix packs and CSUs

are downloaded as interim fixes
are downloaded by Program Temporary Fix (PTF) number
are cumulative