Planning your z/OS UNIX or UNIX System Services environment

Certain processes within the IBM® MQ queue manager (MSTR) and the channel initiator (CHIN) use z/OS® UNIX or UNIX System Services (USS) for their normal processing. Plan your configuration if you do not want to use the default USS configuration.

No special action or customization is necessary in order for IBM MQ to use UNIX services as long as a system-wide default OMVS segment has been set up.

Users who do not want IBM MQ to invoke USS, using the guest or default UID and OMVS segment, need only model a new OMVS segment based on the default segment, as IBM MQ requires no special permissions, and does not run within UNIX as a superuser.

The MSTR and CHIN started task user Ids also need a UID in the RACF OMVS segment.

Note: Although the MSTR and CHIN jobs make use of USS facilities (for example, to interface with TCP/IP services), they do not need to access any of the content of the USS filesystem shipped by IBM MQ. As a result, the MSTR and CHIN jobs do not require any configuration to specify the path for the USS filesystem.

The content of the IBM MQ directory in the USS filesystem is used by applications connecting to IBM MQ. For example, applications using the IBM MQ classes for Java or IBM MQ classes for JMS interfaces.

See the following topics for the relevant configuration instructions: