> does it work if you remove the z option in tar. I have experience some
> problems with my dds2 and dds3 when trying to apply gnuzip to the tar
> archive. I have a ultrix with a tk50 i can do some research in this area
> later and tell how it reacts to the option z in tar.

I'm not disputing that there might be a problem, since I haven't tried
it myself, but the very concept that a TK50 might have problems with
the gnutar -z option amazes me.  How would the TK50 even "know"?

By default, the DDS2 and DDS3 drives attempt to do their own compression,
so if you use the gnutar -z option you will send already comressed data to
them, which they don't expect.  The net result is that the drive actually
*expands* the data somewhat, although typically not back to its original
size.  This is because the drive generally can't detect that the data is not
compressible until it's already been processed, by which time it's too late
to do anything about it.  However, I've never seen this cause any actual
"problems".

If for some reason you *must* use gnutar with "-z" on a DDS/DC or DDS 2-4
drive, for best performance you should configure the drive to disable
its built-in compression.  This can usually be done through either jumper
settings or SCSI commands.