Troubleshooting
Domain Validation
•Path width errors (for example, a Narrow cable used with a Wide SCSI device)
•Damaged or marginal transceivers
•Excessive cross talk
•Excessive system noise
When Domain Validation determines that communication with the target device is not possible at the maximum data transfer rate supported by the HBA (Ultra160), it writes the following warning message to the /var/adm/syslog.log file:
SCSI:Ultra160 SCSI Adapter at hw_path: fallback occurred for target target_ID. Possible causes are improper termination, improper cabling, or malfunctioning hardware. Verify the hardware at the next opportunity.
Later, it “falls back” (lowers the transfer rate and bus width) by one level, according to Table
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