Scsi Cabling Requirements; Setting Scsi Ids - IBM Netfinity 4500R User Reference Manual

Input/Output ports
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IBM® Netfinity® 4500R User's Reference
Inside the server, a SCSI cable connects one of the internal SCSI channel connector to
the hot-swap drive backplane. You can use the other LVD SCSI channel connector, to
connect different types of small computer system interface (SCSI) devices. It can be
used to connect optional devices in the bays below the diskette drive.
Note: If you install a PCI RAID adapter to configure and manage the internal hot-
swap drives, you must move the SCSI cable from the system-board SCSI
connector to an internal channel connector on the RAID adapter.

SCSI cabling requirements

If you plan to attach external SCSI devices, you must order a PCI SCSI adapter and
additional SCSI cables. To select and order the correct cables for use with external
devices, contact your IBM reseller or IBM marketing representative.
For information about the maximum length of SCSI cable between the terminated
ends of the cable, refer to the ANSI SCSI standards. Adhering to these standards will
help ensure that your server operates properly.

Setting SCSI IDs

Each SCSI device connected to a SCSI controller must have a unique SCSI ID. This ID
enables the SCSI controller to identify the device and ensure that different devices on
the same SCSI channel do not attempt to transfer data simultaneously. SCSI devices
that are connected to different SCSI channels can have duplicate SCSI IDs.
The hot-swap-drive backplane controls the SCSI IDs for the internal hot-swap drive
bays. However, when you install an internal SCSI device in a non-hot-swap bay, you
might need to set a unique ID for the device. Refer to the information that is provided
with the device for instructions to set its SCSI ID.