On Tue, 1 Sep 1998, Neil Hoggarth wrote:

> On Mon, 31 Aug 1998, Matthew Jacob wrote:
> 
> > Can you tell me what kind of HP drive this is?
> >  ...
> > At any rate- let me know the inquiry info for this drive
> > so it can be properly put into a quirk table (it may
> > not need to be as the message went away, as you say).
> 
> <HP, HP35480A, T503>
> 
> The marketing name for this is a "SureStore Tape 5000". It's a DDS-1
> drive with DDS-DC data compression.
> 

Ah. Okay.


> > On a related note- when you get the EIO error, what kind
> > of tape do you have in the drive?
> 
> I've tried several - I've got a couple of tapes with dump(8) backups
> from my old system on, and a tar tape which I made with a Sun tape drive
> at work.
> 
> I took the CATS system to bits again and fitted the drive back into the
> RiscPC, so that I could check that the drive and tapes were still okay
> and I hadn't fried anything moving it from one box to the other - the
> tapes still read when I do this.
> 

One of the peculiar properties of DAT is ERASE doesn't really clean
up the tape entirely. If you've recorded in DDS-2 or DDS-3, a DDS-1
or a DDS-1/DC tape drive will barf, and I believe won't be able to
even do an erase to be able to re-record in DDS-1/DC. That's why we
got a bulk tape eraser at Legato, if I recall (my memory is a little
fuzzy on this...).

But if these tapes read fine on the other system but not here, I'd
be curious if there are any related error messages to the EIO- or
if not, wherther SCSIVERBOSE is defined in the kernel or if not whether
you'd like to run a test kernel (some of the commands that are run
at open time are marked as SILENT commands so if they fail you don't
know why).

-matt