Leaving tapes in tape drives?

March 8, 2005 2:41 PM

Is it okay to leave tapes mounted within tape backup drive mechanisms?

Some backups I do give me the option of leaving the tape in the drive after a backup job is complete. I am working with DDS-4, AIT-3 and DLT-2 formats. Are there any downsides to leaving the tape inside the mechanism post-backup, taking it out only between tape head cleanings?

posted by AlexReynolds to computers & internet (12 comments total)

That shouldn't be a problem. I leave my weekly cycle tapes in their DLT1 drives all week, haven't encountered a problem yet.
posted by cmonkey at 3:04 PM on March 8, 2005

One problem could be if your site burns down. If you don't have that tape in an off-site location...
posted by gnz2001 at 3:36 PM on March 8, 2005

Sorry -- tape storage issues notwithstanding. I know about tape cycling. I'm more concerned about damage to the tape itself from being kept in the mechanism on a long-term basis.
posted by AlexReynolds at 3:43 PM on March 8, 2005

I can't speak for DDS or AIT, but DLT drives just sit there doing nothing when they're not being instructed to write/access data.

Also, bear in mind that you don't need to clean your DLT drive unless it specifically requests it - over-cleaning leads to premature head wear. This is a Bad Thing(tm).
posted by coriolisdave at 3:45 PM on March 8, 2005

What sort of time frame are you considering leaving the media in the drive? A week? A month? More?
posted by kuperman at 3:48 PM on March 8, 2005

Physically, tape drives makes a decent storage location for tapes. Presuming the tape drive is in a cool, dry, not too dusty server room.

However, many organizations have a disaster recovery plan that mandates occassional backups be kept offsite. As a rule of thumb, I'd say if data is worth backing up to tape, it is worth moving it offsite occassionally. At a minimum, weekly.
posted by McGuillicuddy at 4:12 PM on March 8, 2005

From experience, what cmonkey said in an AIT drive. One set of tapes per week should be fine.
posted by britain at 5:31 PM on March 8, 2005

Well,

When I work with video tapes (of any variety) we keep them away from the record mechanism. The sort of slack where the tape may be parked often leads to odd tensioning and damage.

Plus it's at the end of the important material.

All tapes (whenever I've been working with that medium) get stored away from the recording mechanism, rewound.
posted by filmgeek at 6:29 PM on March 8, 2005

If the tape is not in the drive, the odds of something overwriting the data you want are a lot lower than if the tape is in the drive. Operator error is easy to do!
posted by mendel at 7:17 PM on March 8, 2005

In terms of head damage, all modern data tapes don't fully mount the tape -- that is, put the tape head to the tape, until the drive is actually accessed. They're built this way because of how most backups work -- the tape is loaded in the morning, but the backups run at night. The heads are pulled well away from the tape whenever there is no data access.

mendel and gzn make good *procedural* points, and it is wise to examine your procedures. Or, in the cant, always mount a scratch monkey before testing.

What we do -- we change out tapes daily, M-F. The monday tapes (friday backup) are further rotated off site in a three-tape cycle (Monday A, B and C) Finally, every calendar month, tape goes offsite for archival purposes.

The problem with this? Tape isn't cheap. Esp given that we deal with several ~.5TB databases and such. However, given the value of the data, and what happens to us if we lose it, tape is damn near free.

The equation may well differ for you. But, fundamentally, there's one basic rule -- don't do something new with the tape until you've gotten good data onto another tape.

BTW, to all of you. Have you tested your restore recently? If not, are you backing up data, or noise?
posted by eriko at 3:54 AM on March 9, 2005

Oh, one common bad thing with A/V -- don't leave a tape in the machine, on play/record, or paused. That leaves the tape against the head. Bad things can happen.

This is a situation that most data drives can't be placed in -- if they aren't moving data, the heads are pulled off the tape.
posted by eriko at 3:55 AM on March 9, 2005

Damn. Let me rewrite that.

Bad = (tape in + (play or record) + paused). The last or above should have been an "and", and play/record implies that both play and record are pressed, which leaves out the case of play and pause.
posted by eriko at 3:57 AM on March 9, 2005