Dave Ewart wrote:
> [...] kernel: st0: Error with sense data: Info fld=0x8000, Deferred st09:00: 
> sns = f1  4
> [...] kernel: ASC=15 ASCQ= 1
> [...] kernel: st0: Error with sense data: Info fld=0x1, Current st09:00: sns 
> = f0  3
> [...] kernel: ASC=15 ASCQ= 2

[repeated]

> What looks like the problem here?  The drive itself?  The SCSI
> controller?  We have a HP DLT-40 drive on an Adaptec 29160 controller.
> There have been no configuration changes to the server.

If it's anything like a DLT4000 drive, Sense4/ASC15/ASCQ1 is
"Hardware error: Random Mechanical Positioning Error" and
Sense3/ASC15/ASC2 is "Medium error: Position error detected
by read of medium".

Or so sayeth my DLT4000 manual, which has also proven accurate
for DLT1 sense codes. Sounds like a hardware problem. :-(