In May I posted our problem that over 50% of our medias got into the
"readonly" state or even "unvailable". Our configuration is

  C20 with a SCSI-2 F/W Wide Adapter 7009 2415
  Exabyte EXB-480 with 4 drives 8505XL
  running ADSM 2.1.0.7

I opened up a call at the beginning of May, 1996 with the IBM hotline,
stating
that I considered the fact to get so many write-error unlikely and
describing
the excate situation.

Finally, I got a feedbackup from the IBM hotline, that there is a known
problem with this kind of SCSI adapter and the Exabyte jukebox in the
middle
of June, 1996. The ROS level of the SCSI adapter should be level 74 (ours
were level 72). Finally, the IBM managed to install a working ROS upgrade
at
the beginning of July, 1996.

So for everbody encountering similar problems, a ROS level upgrade may fix
your problem.

______________________________________________________________________
Disclaimer: These are my views and not those of my employer.

                        Andreas Floeter
Phone: +49 40 74 37 - 48 50     FAX: +49 40 74 37 - 27 55 (or 47 60)
email: Andreas.Floeter AT airbus DOT de

                Daimler-Benz Aerospace Airbus GmbH
Kreetslag 10, 21129 Hamburg; Postfach 95 01 09, 21111 Hamburg, Germany