I used to have similar problem on my DLT drives. The problem was with the
drive microcode. V65 microcode does not record calibration track onto to
tapes correctly. So the drives detected weak signal and thought that
cleaning was needed. After we upgraded the microcode to V80, the problem is
gone. Be noted, tapes used under V65 will still have problem under V80. If
you can restore data on those tapes, just delete the volumes, redefine them,
and then restore data.

Hope this is helpful.

Jie
_____________________________
System and Storage Administrator
ROW Sciences Inc @NCTR FDA
phone: 870-543-7163
fax: 870-543-7382


> -----Original Message-----
> From: Prather, Wanda [SMTP:Wanda.Prather AT JHUAPL DOT EDU]
> Sent: Monday, January 03, 2000 12:52 PM
> To:   ADSM-L AT VM.MARIST DOT EDU
> Subject:      Re: Excessive usage of cleaning cartridge
>
> Yes.  We have this happen frequently.  We sometimes get more than 20
> cleans
> a day, on a total of 7 drives.  Since the cleaning cartridge can only be
> used 20 times, that means the cleaning cartridge becomes ineffective for
> the
> last cleans overnight.
>
> The vendor has no explanation - we've been told that, as you said, the
> cleaning cartridge should last for months.  But it doesn't always work
> that
> way.
>
> We know that many of our cleans are "false cleans", because we see the
> same
> drive getting cleaned many times a day.  The way the DLT7000's are
> designed,
> if one drive writes a tape that is a little misaligned, another drive
> reading that cartridge will detect weak signal strength on the heads, and
> request a cleaning, even though there is nothing wrong that a cleaning
> will
> fix.  So you use up your cleaning tape, which means that when a drive
> really
> DOES need cleaning it can't be cleaned, so that uncleaned drive generates
> more bad tapes, and the whole thing goes downhill.
>
> If you have a problem tape, as you did, and ADSM tries to mount it for
> something like a reclaim, and tries over and over, it may have caused a
> "false clean" each time.  So running the audits may have cleared up your
> problem, or maybe not.
>
> It's a very badly-designed system.  We're replacing our DLT7000's.
>
>
> > -----Original Message-----
> > From: Joyce Woods [SMTP:Joyce.Woods AT ITPMS DOT COM]
> > Sent: Thursday, December 30, 1999 10:48 AM
> > To:   ADSM-L AT VM.MARIST DOT EDU
> > Subject:      Excessive usage of cleaning cartridge
> >
> > Happy New Year Everyone !!!!
> >
> > I have had a problem with the cleaning cartridges on the DLT7000.  I
> have
> > 4
> > drives...but the cleaning cartridge has been getting used up in only 2
> > days.
> > I've had a cleaning cartridge last for 6 months.  Now....I did have
> > problems
> > with a couple of tapes and ran audits to fix the tape.  But, it just
> seems
> > excessive.  Has this happened to anyone else ???
> >
> > Thanks,
> > Joyce