Channel switching

A possible solution to the problem of a channel ceasing to run would be to have two message channels defined for the same transmission queue, but with different communication links. One message channel would be preferred, the other would be a replacement for use when the preferred channel is unavailable.

If triggering is required for these message channels, the associated process definitions must exist for each sender channel end.

To switch message channels:

• If the channel is triggered, set the transmission queue attribute NOTRIGGER.
• Ensure the current channel is inactive.
• Resolve any in-doubt messages on the current channel.
• If the channel is triggered, change the process attribute in the transmission queue to name the process associated with the replacement channel.

  In this context, some implementations allow a channel to have a blank process object definition, in which case you may omit this step as the queue manager will find and start the appropriate process object.

• Restart the channel, or if the channel was triggered, set the transmission queue attribute TRIGGER.