Send unsolicited messages from IMS

To send messages from IMS to an IBM MQ queue, we need to invoke an IMS transaction that ISRTs to an ALTPCB.

We need to write pre-routing and destination resolution exits to route unsolicited messages from IMS and build the OTMA user data, so that the MQMD of the message can be built correctly. See The pre-routing exit DFSYPRX0 and The destination resolution user exit for information about these exit programs.

Note: The IBM MQ - IMS bridge does not know whether a message that it receives is a reply or an unsolicited message. It handles the message the same way in each case, building the MQMD and MQIIH of the reply based on the OTMA UserData that arrived with the message

Unsolicited messages can create new Tpipes. For example, if an existing IMS transaction switched to a new LTERM (for example PRINT01), but the implementation requires that the output be delivered through OTMA, a new Tpipe (called PRINT01 in this example) is created. By default, this is a non-synchronized Tpipe. If the implementation requires the message to be recoverable, set the destination resolution exit output flag. See the IMS Customization Guide for more information.

Parent topic: How the IMS bridge deals with messages