ATTO Technology UL5D LP Troubleshooting Manual page 9

If the issue follows the attached SCSI devices, troubleshoot the attached
devices:
Verify the SCSI devices are powered on.
Check the SCSI devices to make sure that they are all set to different SCSI ID's.
Each device on each SCSI bus must use a unique ID, including the host adapter.
Devices on Bus 1 can have the same IDs as those on Bus 2. By default, the host
adapter uses SCSI ID 7, so devices should use ID's 0 through 6, or 8 through 15.
Check cable integrity. Check the cables for solid connections. Make sure they
are screwed down. Inspect cable ends for bent pins. U320 SCSI requires high
quality cables that are specifically rated for the U320 transmission speeds.
Verify the external terminator is the same SCSI type as the devices (certified as
usable for Ultra320 SCSI or lower) and does not have damaged pins.
Try attaching SCSI devices one at a time with different cables, adding drives and
cables until the problem occurs. This will help pinpoint the device or cable
causing the problem.
Watch the LED indicators on the SCSI devices before, during, and after startup.
Drive lights should also flash at startup as the SCSI bus is scanned. This may
give a clue as to the root cause of the issue.
The UL5D host adapter is detected by the operating system, it detects some of the
connected devices on both SCSI busses, but does not detect all of the connected
devices. The command dmesg can be used to see what devices are detected on each
SCSI bus.
Verify the SCSI devices are powered on.
Check the SCSI devices to make sure that they are all set to different SCSI ID's.
Each device on each SCSI bus must use a unique ID, including the host adapter.
Devices on Bus 1 can have the same IDs as those on Bus 2. By default, the host
adapter uses SCSI ID 7, so devices should use ID's 0 through 6, or 8 through 15.
Check cable integrity. Check the cables for solid connections. Make sure they
are screwed down. Inspect cable ends for bent pins. U320 SCSI requires high
quality cables that are specifically rated for the U320 transmission speeds.
Verify the external terminator is the same SCSI type as the devices (certified as
usable for Ultra320 SCSI or lower) and does not have damaged pins.
Try attaching SCSI devices one at a time with different cables, adding drives and
cables until the problem occurs. This will help pinpoint the device or cable
causing the problem.
Watch the LED indicators on the SCSI devices before, during, and after startup.
Drive lights should also flash at startup as the SCSI bus is scanned. This may
give a clue as to the root cause of the issue.
Page 9 of 12 Atto Technology, Inc. January 19, 2007