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vkrishna2001 · Posted: Mon Nov 24, 2003 5:30 pm Post subject: How to erase a dataset from tape

I created a dataset on tape with expiry date 12-16-2003. But If I want to erase dataset from tape now how I can I do that. I tried TSO DEL. It uncatalogues the dataset but would not erase from tape.

Thanks,
Vijayakrishna

slade · Posted: Mon Nov 24, 2003 8:39 pm Post subject:

Hi Vijay,

Tape datasets are not "erased" when they are deleted (scratched). If the ds was the only one on the tape, the tape can be used again for some other ds (i.e. it becomes a "scratch" tape) and the data from the previous ds is overwritten. There may be ways to get at some the data of the previous ds if the current ds takes less media storage than the prev ds. This would require coding the I/O at the EXCP or SIO level via Assembler.

You didn't mention what (if any) tape mgmt system your shop uses. You also didn't mention why "erasing" the data is required.

The options available to you depend on answers to these ques.

Regards, Jack.

vkrishna2001 · Posted: Tue Nov 25, 2003 10:14 am Post subject:

Hi Jack,

We use CA-1 at our shop. The reason why I want to erase the data is to reuse the tape as I do not require the dataset anymore. There are options on CA-1 to scratch the tape but we do not have access to do it.

Thanks,
Vijay

kok328 · Posted: Thu Nov 27, 2003 1:04 pm Post subject:

You can use DITTO to erase the contents of a tape.
See any DITTO manual for the proper procedures/commands.

slade · Posted: Fri Nov 28, 2003 4:56 am Post subject:

Hi Vijay,

To reuse a tape the data doesn't have to be "erased". So long as you delete the dataset the tape can be reused. The data from the previous dataset will be overwritten upon next use.

The thing causing the problems is the expiration date. Deleting the dataset prior to its expiration date may be problematic. You can contact the tape librarian or the CA-1 Administrator and ask that the dataset be deleted and the tape be returned to the "scratch pool". If (s)he can't do it, (s)he'll know who can.

Regards, Jack.