UNIX for Dummies Questions & Answers

beyond newbie but I figured, what better place to ask than the "dummies" section

Please point me to any online documentation for such a beast if it exists.

thanks

what is JCL?

JCL is job control language on the mainframe. I may be wrong but I tend to think that shell scripting (as a wrapper to a binary program) is an UNIX equivalent to JCL on the mainframe. At least its probably as close as your gonna get.

This is an interesting question that I need answered too, having been in mainframes for years and just moving into unix. The functionality of JCL (Job Control Language) along with JES2 (Job Entry Susbsystem) serves in the mainframes is the following and how do the unix folks handle similar function?

In a production 'batch' environment there are many 'jobs' scheduled (by people) depending on the time the input files are available (created by other jobs that should have run 'succesfully' by that time); each job itself has many tasks that are serially sequenced and down stream tasks depend on the earlier tasks running 'successfully' (indicated by return codes); each task creates output that is useful to either subsequent tasks or other jobs that are scheduled later. Orchestrating this production stream with dependencies especially when intermediate tasks abend is the fun part.

What are the facilities availble in unix to handle large production environments? I can see coding shell scripts for 5 or ten jobs with dependencies two or three deep. Anything more will get one's knickers in a knot. Comments appreciated.

Look into using the Control-M agent on the unix boxes.

Whilst I'm still learning up in my new position using an IBM Mainframe S/390 running Control-M / D / JES2 / SDSF/ etc.; we also run a large number of UNIX systems for our large end financial & insurance application needs. To co-ordinate process flow between hosts, each UNIX system has a Control-M agent that can both capture and set conditions to/from the Mainframe/same UNIX host/other UNIX host/NT host. (Hope that made some sense).

There isn't Mainframe-JCL for the UNIX platform per-se.

HTH's

I know there are plenty of 3rd party scheduling packages that have the kind of functionality you are talking about. A year or so back at my previous job we were looking into them. But they were ridiculously expensive so we didn't buy any.

For example, we had about 10 Unix boxes running Oracle mostly, with only a few users on each box. And the licensing for that tiny environment was going to be $50,000 to $100,000 from the vendors we were talking to. You can see why we gave up on that path and let our developers write some homegrown scripts. If we were much bigger doing it ourself might not have worked, but it was totally unreasonable to pay that much considering how little we had in the environment.

We have our batch flow completely automated, with many complex dependencies and notifications of failure, etc. using CA's autosys . I have had only positive experiences with it. Then again, I don't have to sign the purchase order for the big $$$$ it costs.