CQS administration

This topic describes the system administration tasks associated with using the Common Queue Server.

This topic contains Product-sensitive Programming Interface information.

Recording information necessary for starting CQS
CQS uses the z/OS® system logger to record all information necessary for CQS to recover queue structures and restart. CQS writes log records for each coupling facility list structure pair that it uses to a separate log stream. The log stream is shared among all CQS address spaces that share the queue structure.
Establishing client connection to CQS during failed client takeover
When the client (such as IMS) supports XRF takeover capability, one client must take over the work for a failed client. The CQS connected to this failed client might not be active. Therefore, during the takeover process, the client taking over work from a failed client must connect to a different CQS and indicate that it is taking over work from another client.
Authorizing access to CQS
If RACF® or another security product is installed at your installation, the security administrator can define profiles that control the ability of clients to connect to and access CQS structures.
Using structure alter for CQS
Structure alter is a z/OS process supported by CQS that can be used to alter the structure size or to redistribute the objects within the structure. CQS supports structure alter for primary queue structures, overflow queue structures, and resource structures. CQS allows you to dynamically change the size of a primary or overflow structure.
Using CQS system checkpoint
CQS system checkpoint, the checkpoint data sets that are used for recovery, applies to a CQS if it manages at least one queue structure. If a CQS manages only a resource structure, system checkpoint does not apply.
Using CQS structure checkpoint
Structure checkpoint takes a snapshot of the shared queues on a queue structure and writes the data to the structure recovery data set (SRDS) so that CQS can recover the queues after a structure failure. Structure checkpoint processing copies all recoverable data objects from a structure pair to a SRDS.
Preventing CQS structure full
You should manage structure usage to avoid a structure full condition. If a resource structure or queue structure becomes full, CQS issues message CQS0205E.
Rebuilding structures in CQS
Structure rebuild is a z/OS process that allows another instance of a structure to be allocated with the same name and data reconstructed from the initial structure instance. z/OS supports system-managed rebuild, CQS-managed rebuild, and structure duplexing.

Parent topic: IMS system administration considerations and tasks