REPORT:

I may have found a good workaround for the problem I've been having
with DDS-2 tapes made on TLZ07's and TLZ09's getting parity errors when
read on a different drive. I now use DDS-1 tapes and so far it has been
working fine. To confirm this, I made a full tape on DDS-2 and tried
reading it back on other drives, hoping to see the parity error while
it was reading the tape! But alas, this only happened on one drive and
close to the end of the tape. (Yes, I was expecting worse.) I also made
a DDS-1 tape using the same drive I made the DDS-2 tape on and it read
fine on the drive that couldn't read all of the DDS-2 tape. I don't
know why the drives are suddenly behaving much better, but I'll take my
one positive result (error reading a DDS-2, no error reading DDS-1) as
a good sign that the DDS-1 solution is a good one.

Yes, I know I won't be able to get as much on a tape as with DDS-2, but
I have only one backup job that regularly goes to multiple tapes (with
DDS-1) and that has become a 3-tape job instead of a 2. And I have much
more confidence that I'll be able to read the tapes later even on a
different drive!

AEF