4.15
External SCSI Expansion
External SCSI devices, such as tabletop or rackmounted storage devices, can be
connected to the system using PCI-based SCSI adapters or the embedded external
SCSI port.
SCSI Expansion Rules
Observe the following rules to determine if a particular device can be used:
•
The device must be supported by the operating system. Consult the supported options
list.
•
Do not exceed the maximum number of devices supported on the SCSI controller to be
used.
•
Each device on the bus must have a unique SCSI ID.
•
The entire SCSI bus length, from terminator to terminator, must not exceed the
following limits:
Fast differential SCSI or Ultra SCSI HVD
25 meters
Fast single-ended SCSI
3 meters
Ultra-wide SCSI
1.5 meters
Ultra 2 SCSI LVD
12 meters
Ultra 3 SCSI
12 meters
•
Ensure that the SCSI bus is properly terminated and that no devices in the middle of the
bus are terminated.
•
For best performance, wide devices should be operated in wide SCSI mode.
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hp AlphaServer TS15 Owner's Guide