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How to recover data from Scratch Volume

PostPosted: Wed May 02, 2012 12:34 pm
by prasad029
Hi,

This question is to Storage Management people.
Can any one please help me in the process to restore data from a Scratch Tape Volume.
This tape is a physical tape and currently in scratch status and never been re-written.

Regards,
Prasad

Re: How to recover data from Scratch Volume

PostPosted: Wed May 02, 2012 1:07 pm
by BillyBoyo
Well, I'm not Storage Management. I'd just catalog it :-) First, I'd get hold of it, and not let it out of my sight (or get it in the care of the Ops Supervisor or someone like that). unit=tape,vol=ser=blahbl,disp=(old,catlg) BLP if they are problematic.

The best is for you to talk to your Storage Management, however. They operate the software which does the tape management and will be aware of what do to and what not to do.

Re: How to recover data from Scratch Volume

PostPosted: Wed May 02, 2012 2:24 pm
by NicC
Also, if you know it is a storgae management question why not post in the section of the forum VSAM/SMS the decription of which includes the words 'Storage Management'?

Re: How to recover data from Scratch Volume

PostPosted: Wed May 02, 2012 7:58 pm
by dick scherrer
Hello,

Your topic has been relocated.

If you have the volume in hand, disable the "write-ability" of the volume. If you mount it on the system, it may be detected as a scratch and written on . . .

Talk with your local storage management people and have them run a report of which file(s) are on the volume. When you see the dataset names, re-catalog them if they have been uncataloged.

Also, work with your storage management people to ensure this volume is no longer considered a scratch volume.

Re: How to recover data from Scratch Volume

PostPosted: Thu May 03, 2012 11:08 am
by steve-myers
You really have to work with your storage management people.What I'm describing here is using my best memory for CA-1. I'm sure IBM's RMM can do the same general things, but they will no doubt use slightly different terminolgy.
  • Get a list of the dataset names on the volume. I don't think cataloging the datasets is necessary, but do that if it makes you feel comfortable.
  • Use the tape management software to mark the tape as out of area. This should remove the volume from scratch status. At this point it should be safe to mount the tape, but as has been suggested, fix the tape so it cannot be written on. For old style "round" tape volumes, remove the plastic read/write ring, though many shops remove the tab on the ring to make it difficult to remove this ring. For new style cartridge volumes there is a cylinder knob you rotate to change the volume to no write. The tape library should be able to help you with this.
  • I don't know if this step is really necessary, but have the tape marked as in area. In CA-1 this will disable some of the cross checking it does because of the presumption the tape was altered while it was out of area.
  • Copy the data on the tape using your preferred copy utility. If the data is a disk image copy prepared by ADRDSS or FDR you will have to use these utilities to make the copy.

Re: How to recover data from Scratch Volume

PostPosted: Thu May 03, 2012 2:31 pm
by expat
Are you absolutely positive it is on "real" tape and not virtual tape, as a lot of sites have the VTS set up to erase header info on scratch, and if this is the case then there will probably be absolutely no easy way to do this without a restore of the TMS databases

Re: How to recover data from Scratch Volume

PostPosted: Fri May 04, 2012 12:02 am
by dick scherrer
Hello,

I don't think cataloging the datasets is necessary, but do that if it makes you feel comfortable.
Suggest you make sure the dataset(s) are not already cataloged again by some other process. . .

fwiw.

Re: How to recover data from Scratch Volume

PostPosted: Fri May 04, 2012 12:52 am
by steve-myers
dick scherrer wrote:Hello,

I don't think cataloging the datasets is necessary, but do that if it makes you feel comfortable.
Suggest you make sure the dataset(s) are not already cataloged again by some other process. . .

fwiw.
Actually, Mr. Scherrer raises valid points I didn't think about before.
  • If the datasets on the tape were cataloged before the tape was "scratched" by the tape manager, the tape manager may have uncataloged them. Some other process may have created and cataloged new datasets using the same dataset names as the datasets on the tape. You do not want to interfere with the new datasets if you want to recatalog the datasets on the tape. It may not be possible to catalog these datasets for other reasons.
  • The tape manager may have "scratched" the volume because some other process uncataloged the datasets on the tape. More often than not this is caused by a GDG generation being uncataloged because the generation limit was reached. Do not attempt to recatalog these datasets.
  • The tape manager may have "scratched" the volume because an external tape volume manager such as HSM told the primary tape manager it no longer needed the volume. The datasets on this volume may not be usable by any process other than the original process.
  • It can be painful to recatalog the datasets; the IDCAMS DEFINE NONVSAM(...) (or the IEHPROGM CATLG command) requires a device type that may be difficult to find, as well as other, infrequently used operands.

Re: How to recover data from Scratch Volume

PostPosted: Fri May 04, 2012 2:36 am
by Peter_Mann
prasad029 wrote:Hi,

This question is to Storage Management people.
Can any one please help me in the process to restore data from a Scratch Tape Volume.
This tape is a physical tape and currently in scratch status and never been re-written.

Regards,
Prasad

I have to ask first, is this a backup copy of a DASD dataset?
is this a ADRDSSU backup or FDR or CA-DISK back of a volume that contains the dataset?
I've had some success restoring data from a backup that was in scratch status (CA-1 and CA-TLMS) and once an FDR backup.
if the data you need is needed to retain on tape you can copy to another tape using the copy utility of your choice either way tape or dasd, you'll need to supply a VALID UNIT, VOLSER and LABEL for the scratch tape (INPUT) and for CA-1 or TLMS possibly EXPDT=98000.
Peter

Re: How to recover data from Scratch Volume

PostPosted: Fri Jun 01, 2012 5:00 pm
by Bad Man
I have done this in the past with both CA1 and RMM. All I did was get into TMS(For CA1 there might be a password which is usually TMSMASTER and then U for update and for RMM you have to type in CH) then go to the portion where it says srcatch I changed it to master and then restored Datasets from it...I am assuming that this was a dataset backup tape which has gone to scratch...