Where Did My Tape Drive Go?

[Pete Randall]

I have a C3000 workstation (HP-UX 11.11) with a standalone DLT8000 tape drive (C6378-69201 40/80GB Fast Wide Differential SCSI DLT 8000 desktop tape drive) attached via a SCSI card in slot 5. I've used it in the past to take backups of the workstation but the drive stopped working quite some time ago (months, maybe even a year).

Anyway, I finally got around to replacing the drive, but ioscan no longer detects it. I replicated the SCSI ID used on the old drive, replaced it using the same cable, and connected it to the same slot, but it is now invisible. I rebooted the workstation and searched for boot devices and it showed up there, but once it finishes rebooting, it's vanished again. Any suggestions?


Pete

[Pete Randall]

I forgot to mention that the drivers (tape2, stape) are in the kernel. Things really haven't changed since it used to work.


Pete

[TwoProc]

I've seen this twice:
a) bad scsi terminator
b) bad power supply in the scsi tape drive, it's enough *at times* to let you see the device, and at other times, when other stuff is spinning the power supply can't hold up it's end of bargain on the scsi chain.
Detectable with a meter, and of course, the specs for what voltages you should be seeing on the connector. Or... get the voltages from a working unit, and compare them to the bad unit. When you have a power supply as a participant in a scsi chain that's marginal, it leads you into all sorts of crazy directions, with red herrings in every possible fishing hole.

[Torsten. · Accepted solution]

Hi Pete,

I'm not sure if you remember one of the tape related threads last week, but I told there exactly the same behavior because of a single bent pin.

Visible at BCH, invisible from OS.

[Pete Randall]

John,

Thank goodness I didn't have to get that deeply into it - that could have taken a significant amount of time to troubleshoot.


Torsten,

No, I did not see that thread, but you were absolutely right on. Two pairs of pins were sort of pinched in towards each other, like they may have gotten jammed into the same hole. I spread them apart so they lined up and that did it! Thank you, sir.


Pete

[Torsten.]

You are welcome.

This was the thread:

http://forums.itrc.hp.com/service/forums/questionanswer.do?threadId=1429020

[TwoProc]

Good catch Torsten!