Trace-route messaging

Trace-route messaging is a technique that uses trace-route messages to record activity information for a message. Trace-route messaging involves sending a trace-route message into a queue manager network.

As the trace-route message is routed through the queue manager network, activity information is recorded. This activity information includes information about the applications that performed the activities, when they were performed, and the operations that were performed as part of the activities. We can use the information recorded using trace-route messaging for the following purposes:

To determine the last known location of a message

If a message does not reach its intended destination, we can use the activity information recorded for a trace-route message to determine the last known location of the message. A trace-route message is sent into a queue manager network with the same target destination as the original message, intending that it follows the same route. Activity information can be accumulated in the message data of the trace-route message, or recorded using activity reports. To increase the probability that the trace-route message follows the same route as the original message, we can modify the trace-route message to mimic the original message.

To determine configuration issues with a queue manager network

Trace-route messages are sent into a queue manager network and activity information is recorded. By studying the activity information recorded for a trace-route message, it can become apparent that the trace-route message did not follow the expected route. There are many reasons why this can occur, for example, a channel might be inactive, forcing the message to take an alternative route. In these situations, a system administrator can determine whether there are any problems in the queue manager network, and if there are, correct them.

We can use the IBM MQ display route application to configure, generate, and put trace-route messages into a queue manager network.

• How activity information is recorded
  With trace-route messaging, we can record activity information in the message data of the trace-route message, or use activity reports. Alternatively, we can use both techniques.
• Acquiring recorded activity information
  When a trace-route message has reached its intended destination, or is discarded, the method that we use to acquire the activity information depends on how that information was recorded.
• Control trace-route messaging
  Enable trace-route messaging at the queue manager level, so that applications in the scope of that queue manager can write activity information to a trace-route message. To enable an entire queue manager network, individually enable every queue manager in the network for trace-route messaging. If you enable more queue managers, more activity reports are generated.
• Generating and configuring a trace-route message
  A trace-route message comprises specific message descriptor and message data parts. To generate a trace-route message, either create the message manually or use the IBM MQ display route application.
• Set up a common queue for trace-route reply messages
  To determine the locations of the trace-route reply messages related to a specific message when the reports are delivered to the local system queue, it is more efficient to use a common queue on a single node
• Acquiring and using recorded information
  Use any of the following techniques to acquire recorded activity information for a trace-route message
• Additional activity information
  As a trace-route message is routed through a queue manager network, user applications can record additional information by including one or more additional PCF parameters when writing the Activity group to the message data of the trace-route message or activity report.

Parent topic: Message monitoring

Related concepts

• Trace-route message reference