The JCL configured previously in sample member SQDDB2C can be used to to Mount (execute) the DB2 Log Reader Capture Agent on z/OS.
It is important to realize that the return code, and message from SQDDB2C indicating that the start command was executed successfully, does not necessarily mean that the agent is still in started state. It only means that the start command was accepted by the capture agent and that the initial setup necessary to launch a capture thread were successful. These preparation steps involve connecting to Db2 and setting up the necessary environment to start a log mining session.
The capture agent posts warnings and errors in the system log. The program name for the Db2/z Log Reader Capture is SQDDB2C. If there is a mechanism in place to monitor the system log, it is a good idea to include the monitoring of sqdatalogm messages. This will allow you to detect when a capture agent is mounted, started, or stopped - normally or because of an error. It will also contain, for most usual production error conditions, some additional information to help diagnose the problem.