LTO & DLT Formatting

[Brad Marks]

Hi. I have a bunch of old backups on DLT & LTO tapes that I want to avail to different departments at my company.
I need to be very certain that there is NO WAY for anyone to retrieve data from these tapes.
I ran a DLT and an LTO through our degasser and now neither tape will load. Why is that?

Is there a Unix (I'm running HP-UX 11.i) command that will erase all existing data from a tape? At first I thought of simply backing up /dev/null, but realized that, just because I couldn't see it, the data was still on the tape.

Any help would be greatly appreciated.
Brad

P.S. This thread has been moved from General to Tape Libraries and Drives. - Hp Forum Moderator

[Satish M.S.]

By degaussing the LTO tape either before or after backing up removes the servo track and as such renders the tape useless as the head will no longer have any reference point or 'track' to follow.

For more info. kindly go to www.hp.com and search for the document no.c00023506

[Brad Marks]

Does this also apply to DLTs?

Now that I know what NOT to do, how can I initialize the tapes?
Thanks,
Brad

[Satish M.S.]

You should be able to degauss the DLT tapes.
Kindly look for the following document number on www.hp.com

Document #: lpg50141
Document Title: HP DLT - Degaussing Used DLT IV Tape Media

[Satish M.S.]

Brad:
Sorry for replying in bits and pieces. TO erase all data from a tape, well you really don't have to do it because if you perform a new backup all the older data/contents should be erased.
On the other hand, let's say that you have to destroy the data, try the following:

dd if=/dev/zero bs=8000k of=/dev/rmt/1m

1m being the device number.

Thanks

Satish

[Curtis Ballard]

You asked about reformatting the LTO tape. It can't be done. The servo tracking information is written at the factory and once erased the tapes can not be reused.

I don't have any idea why your DLT tape won't work. I've run a lot of DLT tapes through a degausser and never had a problem.

[Brad Marks]

I executed the
dd if=/dev/zero bs=8000k of=/dev/rmt/2m
command. It took > 24 hours to complete. Is there a means to limit the amount of data that is written to the tape instead of waiting for EOT to occur? I'm only backing up 75 GB of data.

I found an HP Support Document titled "HP DLT - Degaussing Used DLT IV Tape Media" it states that DLT IV tapes written by a DLT70 or DLT80 drive cannot be gegaussed.

Thanks for all of the help and information.
Brad