SCSI CD-ROM disappeared

[Andrew Perrin <clists@perrin.socsci.unc.edu>]

I discovered this while trying to get sound working on my desktop
machine. Basically, a SCSI CD-RW that once worked has simply stopped
working, as far as I can tell.

Details: the SCSI card is:
00:0a.0 SCSI storage controller: LSI Logic / Symbios Logic (formerly
NCR) 53c810 (rev 23)
        Subsystem: LSI Logic / Symbios Logic (formerly NCR) 8100S
        Flags: bus master, medium devsel, latency 32, IRQ 11
        I/O ports at d000 [size=256]
        Memory at e2000000 (32-bit, non-prefetchable) [size=256]
        Capabilities: [40] Power Management version 1


and the CD-RW is an HP CD-Writer:
joehill:/dev# cat /proc/scsi/scsi
Attached devices: 
Host: scsi0 Channel: 00 Id: 04 Lun: 00
  Vendor: IOMEGA   Model: ZIP 100          Rev: E.03
  Type:   Direct-Access                    ANSI SCSI revision: 02
Host: scsi0 Channel: 00 Id: 06 Lun: 00
  Vendor: HP       Model: CD-Writer+ 9200  Rev: 1.0c
  Type:   CD-ROM                           ANSI SCSI revision: 04


I have used it before, both for writing and reading, on this machine so I
know it works adequately. But I can't mount:

joehill:/dev# mount /dev/cdrom /cdrom 
mount: /dev/cdrom is not a valid block device
joehill:/dev# mount /dev/scd0 /cdrom
mount: /dev/scd0 is not a valid block device
joehill:/dev#  mount /dev/sr0 /cdrom/
mount: /dev/sr0 is not a valid block device
joehill:/dev# mount /dev/sr1 /cdrom/
mount: /dev/sr1 is not a valid block device


Two questions:
1.) The small question: how can I tell what device (/dev/*) a given SCSI
device is attached to?
2.) The big question: what should I do to diagnose this?

Thanks.


----------------------------------------------------------------------
Andrew J Perrin - http://www.unc.edu/~aperrin
Assistant Professor of Sociology, U of North Carolina, Chapel Hill
clists@perrin.socsci.unc.edu * andrew_perrin (at) unc.edu