Use user trace for debugging your applications; you can trace brokers, execution groups, and deployed message flows. Start user trace facilities using the mqsichangetrace command or the WebSphere® Message Broker Explorer . Before you start: Before you start to trace a broker, or one of its execution groups or message flows , the broker must be running, and you must have deployed the message flows by using the WebSphere Message Broker Explorer . Follow the instructions in the Packaging and deploying topic. To start a user trace: Start WebSphere Message Broker user trace facilities by using the mqsichangetrace command, or, for execution groups and assigned message flows, from the WebSphere Message Broker Explorer . You can select only one broker on each invocation of the command, but you can activate concurrent traces for more than one broker, by invoking the command more than ...