I've got an internal iomega scsi zip-100 disk here, we should be able to compare and see where things go wrong. First please post the output of this command.
$ cat /proc/scsi/scsi
This should identify if the scsi disk is seen and what ID it is currently set to. This is what mine looks like, you can see the ZIP disk in my list, and you should see your JAZZ disk in your list. Note it does not matter if there is a disk in the drive or not.
Code:
$ cat /proc/scsi/scsi
Attached devices:
Host: scsi0 Channel: 00 Id: 00 Lun: 00
Vendor: MAXTOR Model: ATLAS10K4_36WLS Rev: DFV0
Type: Direct-Access ANSI SCSI revision: 03
Host: scsi0 Channel: 00 Id: 01 Lun: 00
Vendor: MAXTOR Model: ATLAS10K4_36WLS Rev: DFV0
Type: Direct-Access ANSI SCSI revision: 03
Host: scsi0 Channel: 00 Id: 04 Lun: 00
Vendor: PLEXTOR Model: CD-R PX-W4012S Rev: 1.02
Type: CD-ROM ANSI SCSI revision: 02
Host: scsi0 Channel: 00 Id: 05 Lun: 00
Vendor: TOSHIBA Model: DVD-ROM SD-M1711 Rev: 1005
Type: CD-ROM ANSI SCSI revision: 02
Host: scsi0 Channel: 00 Id: 06 Lun: 00
Vendor: IOMEGA Model: ZIP 100 Rev: J.03
Type: Direct-Access ANSI SCSI revision: 02
Host: scsi1 Channel: 00 Id: 00 Lun: 00
Vendor: Generic Model: STORAGE DEVICE Rev: 0125
Type: Direct-Access ANSI SCSI revision: 02
If the Jazz disk shows up, then do the following.
Log in as root this time, and run this command
# tail -f /var/log/messages
Your syslog file may be different on your distro, you'll have to figure out what that is first.
The last 10 messages from the syslog file should be displayed and the command prompt will not return (yet).
Now put the disk in the jazz drive and some new messages should print out within a couple seconds. This is the output I get when I put in my zip disk into the scsi drive, you should see something similar.
Code:
Apr 30 22:24:13 entropy kernel: sdc: Spinning up disk....ready
Apr 30 22:24:13 entropy kernel: SCSI device sdc: 196608 512-byte hdwr sectors (101 MB)
Apr 30 22:24:13 entropy kernel: sdc: Write Protect is off
Apr 30 22:24:13 entropy kernel: sdc: cache data unavailable
Apr 30 22:24:13 entropy kernel: sdc: assuming drive cache: write through
Apr 30 22:24:13 entropy kernel: SCSI device sdc: 196608 512-byte hdwr sectors (101 MB)
Apr 30 22:24:13 entropy kernel: sdc: Write Protect is off
Apr 30 22:24:13 entropy kernel: sdc: cache data unavailable
Apr 30 22:24:13 entropy kernel: sdc: assuming drive cache: write through
Apr 30 22:24:13 entropy kernel: sdc: sdc4
This tells me that to mount my zip disk I'd have to run the following commands as root.
# mkdir /mnt/zip
# mount /dev/sdc4 /mnt/zip
You may need an option, like -t vfat or -t ext2, depending on how your disk was formatted.