Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!samsung!uunet!mcsun!cernvax!chx400!unizh!meyer
From: meyer@ifi.unizh.ch (Urs Meyer)
Newsgroups: comp.sys.sgi
Subject: Re: Re : DAT unit for SGIs
Message-ID: <1990Nov14.104914.3931@ifi.unizh.ch>
Date: 14 Nov 90 10:49:14 GMT
References: <9011082315.AA07404@centrs1.centrcn.umontreal.ca>
Reply-To: meyer@ifi.unizh.ch
Organization: University of Zurich, Department of Computer Science
Lines: 39

In article <9011082315.AA07404@centrs1.centrcn.umontreal.ca> chouinar@centrcn.umontreal.ca (Luc Chouinard) writes:
[...]
>The DAT unit is not yet available for the SGI
>PI and servers because Distributors dont have the SCSI
>drivers specifications.
>
>At the same time (next february) SGI should be announcing
>a DAT unit as a option product for their computers.
>
>I think its a shame that we should wait this long just
>because SGI wants to be in the race with other vendors.
>Even if they were a few months behind other vendors, I
>don't think that they would suffer much.
>
>| Luc Chouinard                   Services Informatiques  |
>| Administrateur de systeme       Universite de Montreal  |
>+---------------------------------------------------------+
>| email : chouinard@CENTRCN.UMontreal.CA                  |

SGI Zurich offers a WangDAT drive distributed by the German company
Solid Computer.  In my opinion it's a pure WangDAT drive.  No
modifications necessary.  It's supposed to run with Irix 3.3 or
higher.  It also runs on a Macintosh with the Retrospect backup
software.  No extra drivers needed.

There is a major problem, though.  I was not able to write/read more
than (say) 300-900 MB on a tape (number is different each time).  It is
not a faulty tape.  We tried it with several brand new tapes.  The
drive stops with an I/O error after some hundreds of MBs.  Sometimes I
can read back the data up to that point, sometimes not.  I think there
are a lot of retries when reading back data.  The data transfer rate
for reading is about 30 kB/sec (!) while it is 90-150 kB/s for writing,
depending on how fast you can supply the data.  (btw, I used tar and
bru with dd or bstreams).

Any expert out there who could give me some insight?

Urs Meyer ---------- meyer@ifi.unizh.ch, {uunet,...}!mcsun!cernvax!unizh!meyer
University of Zurich, Dept of Computer Science, Multimedia Lab, CH-8057 Zurich