Change the cluster-sender channels using a phased approach

Use this option if we are planning on using a staged approach. This process allows you to move to the new cluster-sender channels at various times to suit the needs of our enterprise.


Before starting

  • Identify the business applications, and which channels are used.
  • For the queues we use, display the clusters they are in.
  • Display the channels to show the connection names, the names of the remote queue managers, and which clusters the channel supports.


  • Create a transmission queue. On z/OS you might want to consider which page set we use for the queue.
  • Set up security policy for the queue.
  • Change any queue monitoring to include this queue name.
  • Decide which channels are to use this transmission queue. The channels should have a similar name, so generic characters ' * ' in the CLCHNAME identify the channel.
  • When we are ready to use the new function, alter the transmission queue to specify the name of the channels to use this transmission queue. For example CLUSTER1.TOPARIS, or CLUSTER1.* or *.TOPARIS
  • Start the channels


Procedure

  1. Use the DIS CLUSQMGR(xxxx) XMITQ command to display the cluster sender channels defined in the cluster, where xxxx is the name of the remote queue manager.
  2. Set up the security profile for the transmission queue and give the queue access to the channel initiator.
  3. Define the transmission queue to be used, and specify USAGE(XMITQ) INDXTYPE( CORRELID ) SHARE and CLCHNAME(value) The channel initiator started task user ID needs the following access: 
    alter class(MQADMIN) ssid.CONTEXT.SYSTEM.CLUSTER.TRANSMIT.channel
update class(MQQUEUE ssid.SYSTEM.CLUSTER.TRANSMIT.channel
    and the user ID using the SWITCH command needs the following access: 
    alter cl(MQADMIN) ssid.QUEUE.queuename
  4. Stop and restart the channels.

    The channel change occurs when the channel starts using an MQSC command, or we use CSQUTIL. You can identify which channels need to be restarted using the SWITCH CHANNEL(*)STATUS of CSQUTIL

    If we have problems when the channel is started, stop the channel, resolve the problems, and restart the channel.

    Note that we can change the CLCHNAME attribute as often as we need to.

    The value of CLCHNAME used is the one when the channel is started, so we can change the CLCHNAME definition while the channel continues to use the definitions from the time that it started. The channel uses the new definition when it is restarted.

Parent topic: Implement the system using multiple cluster transmission queues