Systems that run z/VSE are usually part of a larger network consisting of several different platforms. A z/VSE scheduling system must be able to recognize and react to events that originate from these other systems. Unicenter CA-FAQS Production Control System for VSE has a number of ways to do this. The WHEN clause can be used to react to non-PCS controlled events. Or manual work and data stations can be used when human intervention is required. In this article, we will look at automated methods that do not require manual intervention.
The WHEN clause is used to make CA-FAQS/PCS events wait on events that originate from another system. Often a job is FTPed to the POWER reader from another platform. The job then executes on the z/VSE machine. The WHEN clause has the following condition types that can be used to reference the attributes of these jobs:
- $JOB 8 character POWER Job name
- $USE 16 characters of POWER User field
- JOB 8 character DOS JOB name
- MSG 12 character message text
- PHASE 8 character Phase name from VSE EXEC statement
These should be used for external events only. An event that that waits on another CA-FAQS/PCS event should use WHEN conditions GROUP and EVENT, which refer to the CA-FAQS/PCS event.
For example, if you want the event PROCUNIX to run only after the external job FROMUNIX, code the following on the JOLEXPT panel for that event. This panel is the WHEN for event PROCUNIX, accessed by pressing PF10 from the Event Maintenance panel.
If the job runs more than once on your system, use any or all of the Partition ID, CPU ID, or the Time Frame parameters to qualify the trigger event. Use the return or cancel code to make sure the trigger job ran successfully before the CA-FAQS/PCS event is scheduled. It is important to have good job control and naming conventions to help simplify the set up of these event triggers. If the management of the distributed systems is decentralized, consider writing a Power reader exit to enforce the JCL standards.
A CA-FAQS/PCS event can wait on up to eight trigger events. The same WHEN clause can be used in more than one CA-FAQS/PCS event, thus triggering more than one event. Other WHEN TYPES are provided to handle more complex conditions. If a job conditionally executes a program, use the PHASE type to trigger an event that only runs when the specified phase is executed. Use MSG when the program indicates it has taken alternate paths via a message and you want the event to run only when a specific path is taken. All console messages must be scanned for the trigger string. Because of this, it is the most resource intensive of the trigger conditions. It should not be used when one of the other triggers will accomplish the same task.
CA-FAQS/PCS offers a number of ways to use external events to help automate the scheduling process. Good JCL standards and the use of the most simple and direct method of controlling the schedule will give the desired results.