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Tape to disk project

PostPosted: Wed May 14, 2014 7:36 pm
by initechpeter
I need some help as I'm only been a mainframe operator for about 4 years. I have been promoted to my new position of a JCL Specialist. I'm still wet be hide the ears with some JCL or should I say all.

I have been task to change the JCL in our current environment to use DSAD instead of tape (3494). I have a basic concept, but I don't have some to train me in how to understand what needs to be removed from the JCL. I have pasted an example of what I am talking about.

Before my change:

EXEC PGM=IDCAMS
DD SYSOUT=*
DD SYSOUT=*
DD DSN=VUB.PROD1.UBH51S3.INVXREF.CLUSTER,DISP=SHR
DD DSN=UB.MON.UB.B.UBH51S3,DISP=(NEW,CATLG),
DCB=(RECFM=FB,LRECL=80),
UNIT=VTAPE,LABEL=EXPDT=98090,VOL=(,,,10)
DD DSN=SYS2.CTLLIB(UBMOID31),DISP=SHR

After my change:

EXEC PGM=IDCAMS
DD SYSOUT=*
DD SYSOUT=*
DD DSN=VUB.PROD1.UBH51S3.INVXREF.CLUSTER,DISP=SHR
DD DSN=UB.MON.UB.B.UBH51S3,DISP=(NEW,CATLG),
DCB=(RECFM=FB,LRECL=80), <---------------------------------------Can this be removed?????
SPACE=(CYL,(300,200),RLSE)
DD DSN=SYS2.CTLLIB(UBMOID31),DISP=SHR

Re: Tape to disk project

PostPosted: Wed May 14, 2014 7:40 pm
by enrico-sorichetti
NO!

but it would be wiser to add a
UNIT=.....

according to Your organization standards

also when posting source snippets it would be nice to use the code tags
to preserve the alignment

//*45678901234567890
//ddname    DD DSN=......
...
//stepnm  EXEC PGM=....


without the code tags ( cut and pasted from the above )
//*45678901234567890
//ddname DD DSN=......
...
//stepnm EXEC PGM=....

Re: Tape to disk project

PostPosted: Wed May 14, 2014 7:43 pm
by initechpeter
Can you explain why? Isn't that for tape?

Re: Tape to disk project

PostPosted: Wed May 14, 2014 8:03 pm
by BillyBoyo
There's a big JCL Reference manual. For your new position as specialist in JCL, I'd even suggest you print it, so you have a physical copy which you can annotate as well as a "soft" copy you can easily search.

In there, look up UNIT. Get very used to how to look up stuff in that manual. There will be other manuals you'll need to reference, and you need to be fully aware of your site standards.

Re: Tape to disk project

PostPosted: Wed May 14, 2014 9:20 pm
by steve-myers
You have a long way to go.

Data set DCB attributes are required for both tape and disk. The working theory I've had for many years is that one of the goals of the way IBM mainframe disks actually work was to make them operate sort of like a tape drive for sequential data, so DCB attributes must be used for both media, though the BLKSIZE attribute for a disk data set will not necessarily be the same as for the same data set on tape. I noticed you did not specify the BLKSIZE attribute for your proposed disk data set. This is usually fine; the system will create a satisfactory BLKSIZE for the data set. Unfortunately there are times the system will not do the job correctly.

The other thing you must understand is the SPACE parameter for disk data sets and how to translate tape space usage to disk space usage.

As Billyboyo and Mr. Sorrichetti both said, get the JCL Reference manual for your z/OS release and work your way through it. There is also a JCL User's Guide. Personally I find this manual to be essentially useless, but there may be some things in it you may find useful.

By the way, in your attempt to show us an example job, you made two errors; you really should show the entire JCL statement, not just what you think are significant, and for programs like IDCAMS that use control statements specified in an input data set specified by a DD statement with DD name SYSIN, show us the control statements in the data set.

Re: Tape to disk project

PostPosted: Thu May 15, 2014 2:55 am
by NicC
Also, you do not need the DCB keyword - most, if not all, its subkeywords are now keywords in their own right.