ioscan does not find any tape drives in tape library (A55617)

[Umbricht Daniel]

I have a tape library attached to a J5600 (HP-UX 11.00) trough two fiber channel interfaces. Everything worked fine until two days ago when we had to shut down the library to replace a faulted PS. Once the library was powered up again an ioscan -nfC tape was run but no tapes were found (4 Ultrium drives are installed within the library). The robot (autoch) however is found and tapes can be moved around the library using mc command. The SCSI FC channel bridges and the J5600 stayed powered on during the PS swap. To solve the problem I powered down everything, library, FC bridges, j5600 and powered them on in various combinations, e.g. 1st library, 2nd FC bridges and once both devices were up the J5600. ioscan still doesn't find the drives.
Within the ITRC I read something about the fcmsutil command. Could that be of any help.
Daniel

[Umbricht Daniel_1]

I found the problem.
For some weird reason all the tape drive
lost their SCSI ID (SCSI Id: Invalid) during the exchange of the DC Power Supply.
Once the SCSI Ids were set again the tapes showed up in the ioscan output.

[Hoang Chi Cong_1]

Hi.
Yes, last time I had the same problem!
I think there are two ways that cause that problem:
1. Hardware was broken
2. SCSI or cable has corrupt.

Anyway, your case was fix.
Congratulation!

Regard,

Jimkery

[Umbricht Daniel_1]

Hi Jimkery,

as I've written one of the dual DC Power supplies was broken and had to be replaced. What I still don't understand is why the Tape Library lost the SCSI ID of the tape drives.
Is there some backup battery dead on a board
that keeps this information in case of a power down? Can it be caused by a wrong power up sequence of the library, e.g. Powering on the library with a still shut down FC-SCSI Bridge? Anyway the system is up and running again that's what matters at the moment. Daniel

[Hoang Chi Cong_1]

I think there isn't!
Because, last time I have to replace the mother board but there isn't any battery on it!

For your question: I don't know why one of two power supply was died and the FC Brigde had the problem!
Because the Lib must be on *power redundancy* is it right?

Regard,

Jimkery

[Umbricht Daniel]

Since the tape library is up and running,
see comments above, I close this thread.
Daniel