Subject: SONY SDT-7000 DDS-2 drive issues
To: NetBSD User's Discussion List <>
From: Louis Guillaume <>
List: netbsd-users
Date: 11/11/2004 00:34:10

I have a SONY SDT-7000 DDS-2 tape drive...

st0 at scsibus0 target 0 lun 0: <SONY, SDT-7000, 0148> tape removable
st0: drive empty
st0: sync (100.00ns offset 15), 8-bit (10.000MB/s) transfers

... but for some reason I cannot change the density to the correct code 
for DDS-2, i.e. 36...

# mt status
SCSI tape drive, residual=0
blocksize: 0 (0, 0, 0, 0)
density: 19 (0, 0, 0, 0)
current file number: 0
current block number: 0
# mt setdensity 36
mt: /dev/nrst0: setdensity: Invalid argument

This has been so for a very long time (using -current) and I've 
subsisted on pretending that the drive is a plain old DDS drive (code 
19). I use "-a" on dumps and hope for the best.

If anyone can shed some light on a reasonable scenario for backing up to 
these types of drives it would be very helpful...

. Will this drive return "end of media" signals?
. How to tell the length of tape so I can avoid using "-a" with dump?

Please let me know if I can provide more information.