dead DLT drive? (I/O erors, sense data errors, "write filemark" error)

[Matt Morgan]

On 12/19/05, Gene Heskett <gene.heskett at verizon.net> wrote:
> On Monday 19 December 2005 18:46, Matt Morgan wrote:
> >I'm trying, still to get a working Amanda setup. This is on my home
> >system in advance of setting it up for a client next week :-). It's
> >FC4, and the drive is a Quantum DLT 7000, which I think is a 35/70Gb
> >model. It's old.
> >
> >I think the old DLT drive (haven't used it for a few years, but it
> >worked the last time I had it plugged in) may be dead. Here's what I
> >notice:
> >
> >1) The "use cleaning tape" light was on. I plugged in a cleaning
> > tape, and the light went out; but then when I plugged i na real
> > tape, the drive pretty quickly turned the "use cleaning light" back
> > on again. This has happened a few times--the cleaning tape seems to
> > work, but then as soon as I put in a real tape, the drive wants
> > cleaning again.
> >
> How old are your tapes, and under what conditions have they been
> stored?

Well, they're as old as the drive ... and they haven't been stored in
anything like the conditions you recommend :-). I don't let my nice
wines sit around very long in this apartment, for example. I bet
you're right.

Yuck--so now I have to decide whether my project is worth another $40.

>
> Old tape, particularly if its been stored in a humidity exceeding 50%,
> can get quite abrasive and leave large amounts of oxide gunk on the
> heads rapidly.  I'd also see about getting it (the drive) out of its
> skin and making use of a chamois stick moistened with alcohol (not
> rubbing, its got water in it, use paint thinner or better) to gently
> clean the head, making sure you do not rub it sideways, but in the
> same direction the tape travels.
>
> 75F and 80+% relative humidity is death for tape, but only mildly
> uncomfortable for us humans.

It's good to hear someone say this with authority. Back when I was
using these tapes at work, they seemed to go bad a lot, even after
only a couple months. On the tape container the environmental
requirements listed were a little broader. The room was
air-conditioned but not humidity-controlled and this is New York,
where 80%+ humidity is common in Summer.

We were going through enough tapes at the time, and had a redundant
enough backup, that the loss of a few of them wasn't really worth
worrying about in advance of our upgrade to a big LTO library and a
better tape storage system. I always wondered, though.

Thanks,
Matt