IBM Netfinity 3500, Руководство пользователя

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Connecting External Options
Adding External SCSI Devices
The internal SCSI connector provides support for SCSI devices
installed inside the server. The external SCSI connector provides
support for external SCSI devices. The UltraSCSI controller on the
system board can support a maximum of 15 devices.
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 69 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.us.pc.ibm.com/server/
Ÿ
Your server 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 Fast SCSI devices to the
UltraSCSI controller, do not exceed 3 meters (9.8 feet)
total length for all cables (internal and external)
– If you only connect Fast SCSI devices to the UltraSCSI
controller, do not exceed 6 meters (19.7 feet) total length
for all cables.
– If you connect four or less UltraSCSI devices to the
UltraSCSI controller, do not exceed 1 meter (3.3 feet)
total length for all cables.
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, the
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Netfinity 3500 User's Handbook