IBM Netfinity 3000, User Handbook Manual

Page: 168 / 370

Connecting external options
Notes:
Ÿ
If you plan to install both internal and external SCSI
devices, you must follow the instructions given in
“Installing or removing internal drives” on page 102 in
addition to the instructions in this section. Read “Installing
or removing internal drives”; then, return here.
For additional information about SCSI configurations
supported, see http://www.ibm.com/netfinity/
Ÿ
If your server comes with a SCSI adapter, it also comes with
a wide (16-bit) SCSI cable that supports 16-bit devices. If
you want to attach narrow (8-bit) devices to your server,
you must purchase a SCSI 68-pin to 50-Pin Converter that
will enable the connection of the device to the cable that
comes with your server.
Ÿ
It is good practice not to exceed the following cable-length
guidelines:
– If you connect one or more UltraSCSI devices to the
UltraSCSI adapter, do not exceed 1.5 meters (5 feet) total
length for all cables (internal and external).
– If you connect only Fast SCSI devices to the UltraSCSI
adapter, do not exceed 3 meters (10 feet) total length for
all cables (internal and external).
Attention:
In addition to cable length and the number of installed devices, you
must consider other factors that limit the performance of the SCSI
subsystem. For example, if you install UltraSCSI devices in an
external expansion enclosure that is limited to Fast transfer rates, or
if you exceed the previously described cable-length guidelines, the
transfer rate to all SCSI devices must be limited to Fast or standard
transfer rates. You accomplish this by using the SCSISelect Utility
program. See “Using the SCSISelect Utility program” on page 62
for additional information.
If you plan to attach an external SCSI device, you must order an
additional SCSI cable. That is, to use an external device with the
Netfinity 3000 server, you must connect it to the external SCSI
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Netfinity 3000 User's Handbook