Adding a stream

We can add streams manually to allow for data isolation between applications, or to allow inter-operation with Version 6 publish/subscribe hierarchies.


Before starting

Familiarize yourself with the way publish/subscribe streams operate. See Streams and topics.


Use PCF command, runmqsc, or IBM MQ Explorer to do these steps. Note: We can perform steps 1 and 2 in any order. Only perform step 3 after steps 1 and 2 have both been completed.


Procedure

  1. Define a local queue with the same name as the Version 6 stream.
  2. Define a local topic with the same name as the Version 6 stream.
  3. Add the name of the queue to the namelist, SYSTEM.QPUBSUB.QUEUE.NAMELIST
  4. Repeat for all queue managers at Version 7.1 or above that are in the publish/subscribe hierarchy.


Adding 'Sport'

In the example of sharing the stream 'Sport', Version 6 and Version 7.1 queue managers are working in the same publish/subscribe hierarchy. The Version 6 queue managers share a stream called 'Sport'. The example shows how to create a queue and a topic on Version 7.1 queue managers called 'Sport', with a topic string 'Sport' that is shared with the Version 6 stream 'Sport'.

A Version 7.1 publish application, publishing to topic 'Sport', with topic string 'Soccer/Results', creates the resultant topic string 'Sport/Soccer/Results'. On Version 7.1 queue managers, subscribers to topic 'Sport', with topic string 'Soccer/Results' receive the publication.

On Version 6 queue managers, subscribers to stream 'Sport', with topic string 'Soccer/Results' receive the publication. 

runmqsc QM1
5724-H72 (C) Copyright IBM Corp. 1994, 2020.  ALL RIGHTS RESERVED.
Starting MQSC for queue manager QM1.
define qlocal('Sport')
     1 : define qlocal('Sport')
AMQ8006: IBM MQ queue created.
define topic('Sport') topicstr('Sport')
     2 : define topic('Sport') topicstr('Sport')
AMQ8690: IBM MQ topic created.
alter namelist(SYSTEM.QPUBSUB.QUEUE.NAMELIST) NAMES('Sport', 'SYSTEM.BROKER.DEFAULT.STREAM', 'SYSTEM.BROKER.ADMIN.STREAM')
     3 : alter namelist(SYSTEM.QPUBSUB.QUEUE.NAMELIST) NAMES('Sport', 'SYSTEM.BROKER.DEFAULT.STREAM', 'SYSTEM.BROKER.ADMIN.STREAM')
AMQ8551: IBM MQ namelist changed.
Note: You need both to provide the existing names in the namelist object, as well as the new names that we are adding, to the alter namelist command.


What to do next

Information about the stream is passed to other brokers in the hierarchy.

If a broker is Version 6, administer it as a Version 6 broker. That is, you have a choice of creating the stream queue manually, or letting the broker create the stream queue dynamically when it is needed. The queue is based on the model queue definition, SYSTEM.BROKER.MODEL.STREAM.

If a broker is Version 7.1, we must configure each Version 7.1 queue manager in the hierarchy manually.

Parent topic: Configure publish/subscribe messaging