ESP Workload Automation

CA Tuesday's Tip:  CA 7 and Recovery Aids

  • 1.  CA Tuesday's Tip:  CA 7 and Recovery Aids

    Posted 07-15-2014 02:07 PM

    Hello, and Happy Tuesday to all.


    As promised we are discussing the HR50 Recovery Aids.


    The recovery aid reports of CA 7 are available, through the history reporting facility (SASSHIS8). The log data for the timeframe being reported must be intact. This facility can determine the status of the workload that was in the system at the time of failure. It then provides assistance in recovering from such a failure.


    Basically, if you must COLD or FORM start CA 7 (possibly due to DASD failures), you lose the contents of the queue files.  If you COLD start you still have the prior-run queue intact so you can at least query that to determine if certain jobs have run or not, but a FORM start clears all the queues.  If you are planning a queue move or reallocation, you should use the DMPQ type shutdown (Z4 or Z5) and a MOVQ type start—the HR50 Recovery Aids reports and [optional BTI input] file is to be used when you are not able to do the DMPQ/MOVQ operation.


    The input to the SASSHIS8 program (used to obtain the HR50 report/file) is pointed to by the DD UCC7HIST or UCC7ARCH.  The UCC7HIST file is created by the log dump jobs—if you took the defaults, the job names in CA 7 are CA07LOGP and CA07LOGS (JOB= on the DBASE statement in the initialization file if default not used).  These jobs run when the CA 7 log file fills and creates the history and [optionally] the archive files.  You can also use either of the log files on the UCC7HIST DD.  It is strongly recommended that you not concatenate log/history files as this can give unpredictable results.      


    The recovery aid facility provides formatted information from log data reflecting major milestones in the life of each CPU job.  CA 7 logs all internal activity.  With the log records, we are able to determine the status of jobs from a point-in-time.  The reports that are produced by this program include a Last Logged Status of Jobs Report (SASSRA01), a Generated Batch Terminal Interface Commands Report (SASSRA02), and a Simulated LQ Display of Jobs Report (SASSRA03).  The Generated Batch Terminal Interface Commands Report lists DEMAND (or DEMANDH) commands that were generated for the point-in-time and written to the data set pointed to by the COMMANDS DD. A DEMAND(H) command is generated for every job that was in the request, ready, and active queues except those brought in by LOAD(H) or RUN(H) commands. These commands may be useful in restoring the status of the queues following a total system failure that destroyed the contents of one or more of the CA 7 queues.

    To get this report and data set, you must use DEMAND or DEMANDH in the type 50 control statement. DEMANDH is the recommended value if used.  A start time (and optionally an end time) must be entered into the control statement to govern the information to be extracted. The start time must specify a point far enough back in time to ensure that at least one milestone (log record) is included for each job. Otherwise, the job does not appear either in the reports or the generated batch commands. Since a COLD or FORM start clears all of the queues without producing log records, the start time should be prior to the COLD or FORM start. In the absence of an end time in the control statement, log records are extracted until the end-of-file is reached (presumably the point of failure).


    My suggestion to all is to run the SASSHIS8 HR50 report and see the outputs for yourself.  There’s nothing like having this knowledge in advance of a catastrophe (that you hope to never have!)—it could definitely make you a hero.


    Let me know if you have questions or comments on the HR50 reports and perhaps tell the user community how you have used them.


    Until next time—Bye, Ya’ll