External scsi tape drive disappears

[Negasi Gerima]

We have an older model HP-UX machine here running 10.20 that has an external tape drive attached to it. It seems that every so often the tape drive becomes unaccessible for some reason. It is visible when I run "ioscan -C tape -fun". It returns the following results:

$ioscan -C tape -fun
Class I H/W Path Driver S/W State H/W Type Description
=======================================================================
tape 0 10/0/15/0.3.0 stape NO_HW DEVICE ARCHIVE Python 04106-XXX
/dev/rmt/0m /dev/rmt/c2t3d0BEST
/dev/rmt/0mb /dev/rmt/c2t3d0BESTb
/dev/rmt/0mn /dev/rmt/c2t3d0BESTn
/dev/rmt/0mnb /dev/rmt/c2t3d0BESTnb

The problem is that instead of saying "NO_HW", the driver should say "CLAIMED". I've tried running the SAM application but that doesn't seem to pick the drive up at all. Is there something I can do to get this drive working again without calling in a HP service person? Any ideas or suggestions are much appreciated.

[VK2COT]

Hello,

Unfortunately, NO_HW means exactly that.
One or more of the following conditions apply to your case:

The tape drive is faulty
SCSI cable is faulty
SCSI card is faulty
and similar

You need to look at the hardware problem.

Cheers,

VK2COT

[Mridul Shrivastava]

Have you checked the tape drive physically. Is it powered ON and all the cables and terminators are connected firmly ??

Check the above things before calling HP as they will ask the same questions.

[Bill Hassell]

ioscan performs a very simple SCSI ID request to the device and if it fails to return anything, the drive is dead and marked as NO_HW. This isn't a software problem -- replace the drive (after checking cables and any other devices on the same bus).

[Negasi Gerima]

Everyone, thanks for the replies.

We've had the problem in the past where this machine has lost access to the tape drive and it turned out to be the system board rather than the tape drive. If we were to suppose that the issue was with the system board, wouldn't I also see issues with the network connection or usb ports which are also on the same bit of pcb?

I'm just trying to do a bit of baseline troubleshooting before calling support.

TIA,

Negasi

[OldSchool]

"wouldn't I also see issues with the network connection or usb ports which are also on the same bit of pcb"

something here doesn't make sense..."older system" and 10.20, shouldn't have usb ports? And "newer" old boxes (like L-clase) didn't run 10.20

older boxes (like H and K class for example) should have a core i/o board that would have a scsi port, 10BT, modem ports, etc.... The scsi could fail w/o impacting anything else (depending on which components failed). There were also single board scsi adapters that had nothing more than the scsi on them.

[Negasi Gerima]

This unit is a J9000 workstation which according to my research came out in 1999. To the best of my recollection usb made its debut around 1996.

Thanks,

Negasi

[OldSchool]

ah...i had assumed it was a server, not a workstation. sorry 'bout that.

[OldSchool]

and the "servers" didn't support usb on 10.20, some never did.

[Negasi Gerima]

Not a problem. LOL, in our environment workstations routinely see server duty.

[Bill Hassell]

> If we were to suppose that the issue was with the system board, wouldn't I also see issues with the network connection or usb ports which are also on the same bit of pcb?

Not at all. The system board is a bunch of components so unless a common failure such as a power supply was at fault, each component can fail intermittantly and independently. If a memory controller were to fail, everything would crash but a memory chip could fail and the OS may be able to deallocate the bad area of RAM.

So in your case, assuming that the cables and termination are OK, there's 50:50 chance that it's the drive or the SCSI controller on the system board. If this is happening on a replacement board, you may want to try another tape drive.