Promise Technology TX8, TX4 user manual Daisy Chaining Several UltraTrak100s Together

UltraTrak100 TX4 and UltraTrak100 TX8 User Manual

(the one which is attached to the SCSI adapter) to the top connector, and place an LVD SCSI active terminator on the other connector. An LVD SCSI active terminator is included with UltraTrak100 disk array unit.

•If the array is to be placed in the middle of a daisy-chained configuration, connect the incoming cable (the one which is attached to the SCSI adapter) to the top connector and connect the outgoing cable (the one which continues on to other devices) to the other connector. In this case, no terminator is required at the array, but the last device in the daisy chain must be terminated.

Correct SCSI termination procedures require that the first and last devices on the SCSI bus be terminated. If the first or last device is not terminated, or if devices other than the first and last are terminated, erratic SCSI bus performance will occur. Typically, the system or host adapter is the first device and is already terminated. When installing the UltraTrak100 disk array on a SCSI bus with other devices, make sure the above rules are observed with all devices on the SCSI bus. Consult your system and/or host adapter manual for additional information on correct termination procedure.

Caution

Improper system operation will occur if the SCSI termination is incorrect. Active termination and SCSI-3 compliant cables must be used. A SCSI-3 compliant cable is included with the UltraTrak100.

DAISY CHAINING MULTIPLE ARRAYS

Use a standard 68-pin SCSI-3 cable assembly to attach the array to the SCSI chain. Attach each cable to the individual units to be connected on the SCSI bus. Ensure that each device has a unique SCSI ID and that only the first and last devices are terminated.

			Terminator
Computer or	UltraTrak100 TX4	UltraTrak100 TX4	UltraTrak100 TX4
Workstation

Figure 3. Daisy Chaining Several UltraTrak100s Together

DAISY CHAINING WITH OTHER SCSI DEVICES

This procedure is essentially the same as the procedure outlined above for multiple arrays. Refer to the manual associated with the other device or devices for additional information that may be pertinent to that unit. Ensure that each

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