Configure a shared input queue for message flows
The broker uses WebSphere® MQ queue-sharing groups on z/OS®.
Queue managers that can access the same set of shared queues form a group called a queue-sharing group (QSG) and they communicate with each other by means of a coupling facility (CF) that stores the shared queues. A shared queue is a type of local queue whose messages can be accessed by one or more queue managers that are in a QSG.
To further enhance the availability of messages in a QSG, WebSphere MQ detects if another queue manager in the group disconnects from the CF in an unusual way, and completes pending units of work for that queue manager where possible; this is known as peer recovery.
WebSphere MQ Version 7 product documentation online, and perform the following
steps:- Add a QSG to the DB2® tables
- Add a queue manager to a QSG
- Create the shared queue as a member of the QSG
Define a serialization token
Define the same value for the serialization token attribute for each MQInput node that is required to access the shared queue.
- Ensure that the Coupling Facility Structure is at CFLEVEL(3) or
above, and that you set RECOVER=YES.
If you do not do this, when an MQInput node attempts to get a message from the shared queue, the action fails with the WebSphere MQ return code BIP2048 (MQRC_PERSISTENT_NOT_ALLOWED)
- Set the Backout Threshold for the shared queue to at least 2.
This value prevents input messages that are in progress being sent to the Dead Letter Queue because, during recovery, a message is restored to the input queue before another broker is able to get it and resume processing.
Last updated Friday, 21 July 2017