Subject: Re: scsi DLT tape drives
To: None <port-i386@NetBSD.org>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: port-i386
Date: 07/07/2004 12:09:53
> I just put together a box with [mpt0 scsi card] and two [FUJITSU,
> MAS3735NP disks.]  When I plugged the [<BNCHMARK, DLT1, 5032> tape]
> in, sd0 and sd1 disappeared.  Tech support is claiming this is
> normal, and that the tape has to be the only scsi device on the bus.

They are out of their tree.  I suppose it could be true, but if so the
device is so catastrophically broken it should immediately be returned
and something that actually _does_ speak SCSI obtained in its place,
since this drive clearly doesn't.  There is no excuse for that level of
brokenness.

My guess too is termination issues.  You say you "added" the tape
drive, which sounds as though it's not last on the chain.  If it has
unremovable termination (which would be arguably a brokenness, but a
lesser brokenness), this can upset the bus.  Try removing the
terminator and putting the tape at the end of the bus.

However, the errors you quote from the tape drive by itself lead me to
suspect it may actually be broken.

Andy Ruhl adds
> You REALLY don't want to be running a tape drive and a disk drive on
> the same channel.  If your card has another channel, use it.  If not,
> invest in another card.

but gives no clue what reason, if any, is behind this.

I can't see any reason for this unless the tape drive doesn't support
disconnect/reconnect, which anything even vaguely modern should.  (The
"DLT1" in the tape drive probe message implies it's a DLT drive, which
qualifies as "modern" here.)  Andy, am I missing something?

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