Chapter 3. Installing the Library
18
Library Requirements
Before installing the Spectra T24 library in your data storage environment, read the
following sections on library requirements:
•
SCSI Requirements
, below
•
Host Bus Adapters (HBAs)
on page 19
SCSI Requirements
The Spectra T24 library incorporates a wide SCSI-2 or SCSI-3 low-voltage differential
(LVD) SCSI bus, but may also be attached to a single-ended (SE) SCSI bus. Make sure
that your SCSI host bus adapter (HBA) or controller supports these standards. If you
connect the library to an SE SCSI bus, or if there are SE devices attached to the same
SCSI bus, the library’s performance is limited to the maximum data transfer speed and
maximum cable lengths of the SE bus. For these reasons, Spectra Logic strongly
recommends that you do not use an SE SCSI bus with the library.
Note:
Do not connect an LTO-3 device to an SE SCSI bus, as an SE bus
will severely degrade performance.
Note:
The Spectra T24 library is
not
compatible with a standard
differential (Diff) SCSI bus or a high-voltage differential (HVD)
SCSI bus.
This library
is
compatible with a narrow (50-pin) SCSI bus using a
68-pin to 50-pin adapter that terminates the unused 18 pins,
sometimes labeled high-byte termination.
Note that the adapter is not included with the library.
A single-ended SCSI HBA will severely degrade performance and limit cable length.
Also, if there are any SE devices on the same SCSI bus, the entire SCSI bus will
negotiate down to SE speed, severely degrading performance.
