Hello all, long time listener, first time caller.
I have a real doozie on my hands here. I've been administrating
*NIX machines of various flavors for years, and this is a first for me.
After taking the plunge and buying a pair of Sony SDX-300 tape
mechanisms, I have stumbled into an absolutely befuddling behavior. Two
identical machines (same NCR 53c810 SCSI card, same 2.0.36 kernel, same
CPU, same brand of cables etc.) in different locales: one sits in an
office in Tucson AZ, and the other sits up at 8500' on Mt. Bigelow.
The one downtown works great all the time, no trouble.
The one at altitude whines constantly, and cannot be trusted. One
time, it writes 15 Gb of data and reads it back no trouble, and the next
day it coughs and complains on the very same tape:
Dec 16 14:59:24 bigspcz kernel: st0: Error with sense data: Current error
st09:00: sns = f0
3
Dec 16 14:59:24 bigspcz kernel: ASC= c ASCQ= 0
Dec 16 14:59:24 bigspcz kernel: Raw sense data:0xf0 0x00 0x03 0x00 0x00
0x00 0x05 0x14 0x00
0x00 0x00 0x00 0x0c 0x00 0x00 0x00
Dec 16 14:59:24 bigspcz kernel: st0: Error with sense data: Current error
st09:00: sns = f0
3
Dec 16 14:59:24 bigspcz kernel: ASC= c ASCQ= 0
Dec 16 14:59:24 bigspcz kernel: Raw sense data:0xf0 0x00 0x03 0x00 0x00
0x00 0x01 0x14 0x00
0x00 0x00 0x00 0x0c 0x00 0x00 0x00
Dec 16 14:59:24 bigspcz kernel: st0: Error on write filemark.
Dec 16 14:59:36 bigspcz kernel: st0: Error with sense data: extra data not
valid Current err
or st09:00: sns = 70 3
It repeats this about 3 times and quits. The st device driver and
SCSI support are built in, not modularized. I shutdown the machine, take
it downtown to 2000 feet altitude, and it purrs like a kitten. Tapes which
previously gave read or write errors first time from the wrapper work
great.
The machines are running on UPS's with line filters, so the power
is good. The -BEST- part about this is that when I switch the one from
downtown to the mountain and vice-versa, then the machine which previously
worked for dozens of cycles gives the same error. Swapping one drive
mechanism, different media, one SCSI card for another, etc. All the same
error. Only thing I notice is that the drive seems to run hot, i.e. when I
remove a tape from it is it uncomfortable to touch. I may just put a
temperature probe on the tape after a few hours in there and measure it.
According th Sony, the drive should work at 10,000', which we're a far cry
from. Humidity is maybe 35%, room temperature is about 70F at the mountain
site.
Has anyone seen anything like this? Is anyone using these drives
with Linux at altitudes like this sucessfully? Am I finally losing my
last shred of sanity?
Thanks for any experience/advice,
John
John Brownlee
Lunar and Planetary Lab
University of Arizona
jonnie @ lpl . arizona . edu
