From: John F. Woods <jfw@jfwhome.funhouse.com>
> > > > on boot as a "Conner CTMS 3200 7.15".  It takes QIC3080
> > > > tapes and supposedly is capable of storing 2GB
> > > > (uncompressed) on each tape.
>
> I've had both the CTMS-3200 and the successor CTMS-8000 (which holds 4G on
> TR-4 Travan cartridges), and they both work perfectly well on x86-based
> NetBSD.  The only quirk I noted was that the drive is limited to logical
block
> sizes of something like 24KB per block; the early CTMS-3200 drive I had
would
> lock up solid trying to read a tape written with a blocksize larger than
that.

I too have both a CTMS-3200 and a Seagate CTT-8000.  Both probe the same:

    scsibus0 targ 4 lun 0: <CONNER, CTT8000-S, 1.17> SCSI2 1/sequential
removable not configured
    probe(ncr0:4:1): 5.0 MB/s (200 ns, offset 8)

Of course, the CTT8000-S part is replaced with CTMS-3200 on the older drive.
;-)

For backups, I do:

    tar --create --file /dev/nrst0 --block-size
16 --gzip --block-compress --verbose --totals --sparse --exclude-from
backup.exclude /

On the CTMS-3200, I could use a --block-size 32, but that seems to hose
things up on the CTT-8000.  Any definititive 'best blocksize' to use?

(On a similar note, is there any way I can get the --exclude-from
functionality calling pax directly?)

I've not tried dump (I prefer tar for backups), but you should be able to
tell dump the tape-size manually...IIRC the 400M limit is basically a 'safe
guess' when it gets confused.