Resolving in-doubt channels
If there is no possibility that a link that has been lost might recover, you must resolve an in-doubt channel by either backing out or committing the messages.
About this task
The sending end of a channel might be holding messages in-doubt because, for example, it has lost the connection with the receiving end of the channel. If there is no prospect of the link recovering, the channel must be resolved either to back out the messages (restore the messages to the transmission queue) or commit the messages (discard the messages).
To resolve a channel, complete the following steps.
Procedure
- Find out the last committed Logical Unit of Work ID (LUWID) for each end of the channel:
- In the Content view, right-click the channel definition at one end of the channel, then click Status... The Status dialog for that channel definition opens.
- In the Status dialog, look for the value in the Last LUWID column. This value shows the ID of the last logical unit of work that was committed by the channel. Make a note of the value.
- Repeat Steps 1 and 2 for the channel definition at the other end of the channel.
- In the Content view, right-click the sending end of the channel, then click Resolve... The Resolve dialog opens.
- In the Resolve dialog, select the method with which to resolve the channel:
- If the LUWID at the sending end of the channel is the same as the LUWID at the receiving end of the channel, click Commit to commit the messages and discard the messages from the transmission queue.
- If the LUWID at the sending end of the channel is different from the LUWID at the receiving end of the channel, click Back out to back out the unit of work and retain the messages to the transmission queue so that the messages can be re-sent.
Results
The channel is no longer in doubt and the transmission queue can be used by a different channel to re-send the messages.
For more information, see Distributed queueing and clusters in the IBM MQ online product documentation.