Silicon Graphics TP9100, Installation Instructions And User Manual

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3: Using TPM
Operation
It is important for the administrator to know how physical device selection works,
because it can serve as a good general debugging tool in the event that your computer
does not “see” a specific LUN. The algorithm is the same, regardless of the operating
system. In summary, TPM executes the following steps:
1. Creates a list of all SCSI and FC device drivers.
2. Issues a standard SCSI inquiry command to report the drive Vendor ID and Product
ID fields. If the inquiry fails, TPM assumes the device driver is no good, and skips to
the next driver in the list.
3. Issues the vendor-specific Inquiry command to determine if the device is a logical
drive within a RAID subsystem. If so, it issues additional commands to report
which controller and World Wide Name (WWN) is associated with that LUN.
4. Builds the record and reports what it has discovered if either the Vendor or Product
fields are non-blank.