w w w . d e l l . c o m s u p p o r t . d e l l . c o m

Perform the following steps to connect SCSI devices:

1Disable termination on any SCSI device that does not sit at the end of the SCSI bus.

2Configure all SCSI devices to supply termination power (TermPWR.)

3Set proper target IDs (TIDs) for all SCSI devices.

Cable Suggestions

System throughput problems can occur if SCSI cable use is not maximized. You should:

Use cables up to 12 meters for LVD devices.

For single-ended SCSI devices, use the shortest SCSI cables (no more than 3 meters for Fast SCSI, no more than 1.5 meters for an 8-drive Ultra SCSI system, and no more than 3 meters for a 6-drive Ultra SCSI system.)

Use active termination.

Avoid clustering the cable nodes.

Note that 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 either flat or rounded and shielded or non-shielded.)

Note that ribbon cables have fairly good cross-talk rejection characteristics.

Step 7—Set Target IDs

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 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.

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