HP D7171A - NetServer - LPr Installation Manual page 28

Hewlett-Packard NetRAID-4M Controller Installation Guide
– Three meters (9.8 feet) if you are using Fast SCSI data transfer
speeds (up to 20 MBytes/second).
When calculating the total length of cabling on each channel,
be sure to include the cabling inside any array enclosure and
the host system.
Use good-quality SCSI cabling, and minimize the stub lengths.
Symptoms of SCSI cabling-related problems include drives
that are not recognized, drives that are locking up, and drives
that are deactivating.
SCSI ID Numbers
Each device attached to a channel (Channel 0, 1, 2, or 3) on the
HP NetRAID-4M, as well as the HP NetRAID-4M itself, must be
assigned a unique SCSI ID number from 0 to 15 — no duplicate IDs
are permitted on a channel.
The HP NetRAID-4M is set to SCSI ID 7 on each channel by
default.
SCSI ID 7 has the highest priority on the channel. The priority
of the remaining IDs, in descending order, is 6 to 0, 15 to 8.
If you have 8-bit SCSI devices, they must use SCSI IDs 0, 1, 2, 3,
4, 5, or 6. (To change the SCSI ID on your hard disk and other
SCSI devices, refer to the devices' documentation.)
Use the SCSISelect Utility to change the HP NetRAID-4M's
SCSI device ID assignments. (See Appendix A, Using the BIOS
SCSISelect and Disk Utilities).
Note:
Normally, you should leave the SCSI ID of the
HP NetRAID-4M set to its default.
SCSI Termination
To ensure reliable communication, terminators must be installed (or
enabled) on the devices at the physical ends of each channel. The
terminators on all devices that lie between the physical ends must be
removed (or disabled).
Hewlett-Packard internal/external disk enclosures are self
terminating.
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