If you receive CA-7.306 - ** WARNING ** 80% TRAILER QUEUE UTILIZATION ** WARNING ** it could be that retained JCL is causing the space usage.
On the DB.1 (CA 7 CPU JOB DEFINITION) screen, the RETAIN-JCL field can be set to Y so that the last successful run of a job's JCL is kept in the trailer queue. You can access this JCL with the FEP function on the QM.5 (QJCL) screen. To see if you have any jobs holding tracks in the trailer queue for retained JCL, you can enter the CA 7 top line command:
PRRNJCL,UPDATE=NO
This will bring back a list of jobs whose last-run JCL is currently held in the trailer queue. If you use UPDATE=YES on the PRRNJCL command, all retained JCL will be deleted freeing the tracks from the trailer queue. You can also delete the retained JCL by specific job, date range, or age with the PRRNDEL command. On the DB.1 screen the DELPRRN function can also be used to delete the Prior Run JCL for a specific job. For information on how to increase the size of the trailer queue, please see technical document Increase trailer queue