Trace-route message format

Trace-route messages are standard IBM® MQ messages containing a message descriptor and message data. The message data contains information about the activities performed on a trace-route message as it has been routed through a queue manager network.

Trace-route messages contain the following information:
A message descriptor
An MQMD structure, with the Format field set to MQFMT_ADMIN or MQFMT_EMBEDDED_PCF.
Message data
Consists of either:
  • A PCF header (MQCFH) and trace-route message data, if Format is set to MQFMT_ADMIN, or
  • An embedded PCF header (MQEPH), trace-route message data, and additional user-specified message data, if Format is set to MQFMT_EMBEDDED_PCF.
When using the IBM MQ display route application to generate a trace-route message, Format is set to MQFMT_ADMIN.

The content of the trace-route message data is determined by the Accumulate parameter from the TraceRoute PCF group, as follows:

  • If Accumulate is set to MQROUTE_ACCUMULATE_NONE, the trace-route message data contains the TraceRoute PCF group.
  • If Accumulate is set to either MQROUTE_ACCUMULATE_IN_MSG or MQROUTE_ACCUMULATE_AND_REPLY, the trace-route message data contains the TraceRoute PCF group and zero or more Activity PCF groups.
Table 1 shows the structure of a trace-route message.
Table 1. Trace-route message format
MQMD structure Embedded PCF header MQEPH structure Trace-route message data
Structure identifier
Structure version
Report options
Message type
Expiration time
Feedback
Encoding
Coded character set ID
Message format
Priority
Persistence
Message identifier
Correlation identifier
Backout count
Reply-to queue
Reply-to queue manager
User identifier
Accounting token
Application identity data
Application type
Application name
Put date
Put time
Application origin data
Group identifier
Message sequence number
Offset
Message flags
Original length
  
Structure identifier
Structure version
Structure length
Encoding
Coded character set ID
Message format
Flags
PCF header (MQCFH)
Structure type
Structure length
Structure version
Command identifier
Message sequence number
Control options
Completion code
Reason code
Parameter count
  
TraceRoute
Detail
Recorded activities
Unrecorded activities
Discontinuity count
Max activities
Accumulate
Deliver