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Step 6. Connect SCSI Devices to the Storage Adapter
Use SCSI cables to connect SCSI devices to the storage
adapter.
To connect the SCSI devices:
1. Disable termination on any SCSI device that does not sit at
the end of the SCSI bus.
2. Configure all SCSI devices to supply TERMPWR.
3. Connect cables to the SCSI devices. The maximum cable
length for Fast SCSI (10 Mbytes/s) devices or SE is 3
meters; it is 1.5 meters for Ultra SCSI devices; it is
12 meters for LVD devices. You can connect up to 15 Ultra
SCSI devices to each SCSI channel.
System throughput problems can occur if SCSI cables are not
the correct type. To minimize the potential for problems:
–
Use cables no longer than 12 meters for Ultra160 and
Ultra320 devices.
–
For SE SCSI devices, use the shortest SCSI cables (no
longer than 3 meters for Fast SCSI, no longer than 1.5
meters for an 8-drive Ultra SCSI system, and no longer
than 3 meters for a 6-drive Ultra SCSI system).
–
Use active termination.
–
Avoid clustering the cable nodes.
–
The cable stub length must be no greater than 0.1 meter
(4 inches.)
–
Use high impedance cables.
–
Route SCSI cables carefully.
Step 7. Set SCSI Termination
The SCSI bus is an electrical transmission line and must be
terminated properly to minimize reflections and losses. Set
termination at each end of the SCSI cable(s).
For a disk array, set SCSI bus termination so that removing or
adding a SCSI device does not disturb termination. An easy
way to do this is to connect the storage adapter to one end of
the SCSI cable and to connect an external terminator module
Detailed Installation
Copyright © 2003 by LSI Logic Corporation. All rights reserved.
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