Step 10: Set Target Ids - LSI MegaRAID SCSI 320-2 RAID Controller Series 518 Hardware Manual

6.2.9.1 Cable Suggestions

6.2.10 Step 10: Set Target IDs

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Use this procedure to connect 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. Set proper target IDs (TIDs) for each SCSI device.
4. Distribute SCSI devices evenly across the SCSI channels for
optimum performance.
5. Do not exceed the maximum cable length for the number and type
of SCSI devices you are using. (See
6. Try to connect all non-disk SCSI devices to a SCSI channel that has
no SCSI disk drives connected to it.
System throughput problems can occur if SCSI cable use is not
maximized. Here are some cabling guidelines:
Use the shortest SCSI cables.
LVD mode cable lengths should be no more than 25 meters with two
devices and no more than 12 meters with eight devices.
Use active termination.
Avoid clustering the stubs.
Cable stub length should be no more than 0.1 meter (4 inches).
Route SCSI cables carefully.
Use high-impedance cables.
Do not mix cable types (choose flat cable for inside the enclosure,
and round shielded cables for outside the enclosure.)
Ribbon cables have fairly good cross-talk rejection characteristics.
Set target identifiers (TIDs) on the SCSI devices. Each device in a
specific SCSI channel must have a unique TID in that channel. Non-disk
devices (CD-ROM or tapes) should have unique SCSI IDs regardless of
the channel where they are connected. See the documentation for each
SCSI device to set the TIDs. The MegaRAID SCSI 320-2 controller
Hardware Installation
Copyright © 2002 by LSI Logic Corporation. All rights reserved.
Table 1.1 for details.)