Bus Length

For UltraSCSI performance on the external SCSI bus, you must adhere to the following bus length restrictions for daisy-chained SCSI devices:

• For 1 to 3 devices, the maximum bus length is 3 meters (9.84 feet)

• For 4 to 7 devices, the maximum bus length is 1.5 meters (4.92 feet)

You must include the Enterprise 250 internal bus length (0.5 meter/1.7 feet) in your bus length calculations.

If you exceed these bus length restrictions, UltraSCSI devices may operate at less than 40 Mbytes/sec. Under such conditions, an UltraSCSI device may experience errors that eventually cause it to reset and operate at 20 Mbytes/sec.

For Fast/Wide performance on the external SCSI bus, the maximum SCSI bus length for daisy-chained SCSI devices is 6 meters (19.7 feet), including the Enterprise 250 internal bus length (0.5 meter/1.7 feet).