News Stay informed about the latest enterprise technology news and product updates.

Mainframe Mishap: Well earned exits

Years ago, Steven Kimball accidentally shut off his company's production CICS system at 10 o'clock in the morning. As a result, his boss assigned him the task of making sure no one would be able to do that again. Read his story.

Now, the mainframe is known for being very robust and reliable. But the human beings operating them are not always.

This is the first installment of Mainframe Mishaps, a new feature on If you have a funny, illuminating or educational story about mainframe mishaps, please send it here.

Steven A. Kimball of Aetna submitted this story:

Years ago as a CICS system programmer, I was testing (just beta-released) terminal autoinstall under CICS 1.7, on one of my play test LPAR CICS regions. About that time, I then got a beeper alert that one of our larger volume production regions was having a problem. I dropped what I was doing in test, toggled up another host VTAM session using RUMBA and logged onto the production CICS region to research problem.

A while later, after the prod problem was resolved, I returned to my test work and decided to shut down my play region to pick up the flavor of the autoinstall program. I issued CEMT PERFORM SHUT and found out several minutes later (you guessed it) that I had just accidentally shut down the production (2 million transactions per day) CICS at 10 o'clock in the morning. My supervisor, soon thereafter, assigned me the task of writing XZCATT/XZCIN global User exits that would interrogate tranid for 'CICS' and if it was, look for 'perform shut'. If so, change tranid to 'SHUT' instead. SHUT tranid would throw up a BMS map that would ask user for confirmation that region shutdown was, in fact, intended to be shut down.

Pretty challenging stuff for a novice ASM programmer new to CICS; particularly because as we all know, the edits of the TIOA area needed to test for all combos of:

* Perf Shut
* perf shu
* Perfor    Shut
* P      Shut
* perform        shu
* You get the idea!

My exits stayed in place until CICS 4.1 was traded in for a new version ... after that, we did away with all user mods, included my well earned exits.

Dig Deeper on IBM system z and mainframe systems

Start the conversation

Send me notifications when other members comment.

Please create a username to comment.