IBM 865951Y - Netfinity 5000 - 51Y, Hardware Maintenance Manual

Page: 102 / 220

External options
The information in this section supplements the instructions
that come with the external options (SCSI drives, printers,
modems, and other serial and parallel devices). To
connect external options, see the documentation that
comes with the options.
Adding External SCSI devices:
The server
comes with a 16-bit UltraSCSI controller on the system
board, which provides two independent SCSI channels.
This controller has two 68-pin, shielded, high-density
connectors: one internal, on the controller, and one
external, on the back of the server. You can use these
connectors to install an additional internal SCSI device in
the server or to attach up to fifteen external SCSI devices
to the server.
The internal SCSI connector provides support for SCSI
devices installed inside the server. The external SCSI
connector provides support for external SCSI devices.
Notes
Ÿ
If you plan to install both internal and external
SCSI devices, you must follow the instructions
given in “Internal drives installation or removing”
on page 113 in addition to the instructions in this
section. Read “Internal drives installation or
removing,” and then return here.
For additional information about SCSI
configurations supported, see
http://www.ibm.com/pc/us/netfinity/
Ÿ
Do not exceed the following cable lengths:
– If you connect one or more Fast SCSI
devices to the SCSI controller, the total
length of all cables (internal and external)
must not exceed 3 meters (9.8 feet).
– If you do not connect Fast SCSI devices to
the SCSI controller, the total length of all
cables must not exceed 6 meters (19.7
feet).
You must set a unique SCSI ID for each external SCSI
device so that the controller can identify the devices. The
controller can then ensure that different devices do not
attempt to transfer data at the same time. Therefore, do
not set the SCSI IDs for external devices to the values you
used for the controller.
If you plan to attach an external SCSI device, you might
need to order an additional SCSI cable. To use an
external device with the Netfinity 5000, you must connect it
to the external SCSI connector, using a SCSI cable. This
SCSI cable must have the proper connector for the SCSI
external connector on one end, and the proper connector
94
Netfinity Server HMM