IBM Netfinity 5100 8658 21Y, Manual

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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
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
attach SCSI devices to the external SCSI connector, you
must set a unique ID for the device. Refer to the
information that is provided with the device for instructions
to set its SCSI ID.
SCSI connector pin-number assignments
The following table shows the pin-number assignments for
the 68-pin SCSI connectors.
34
1
68
35
Table 17. 68-pin SCSI connector pin-number assignments
Pin Signal Pin Signal
1 +Data 12 35 -Data 12
2 +Data 13 36 -Data 13
3 +Data 14 37 -Data 14
4 +Data 15 38 -Data 15
5 +Data P1 39 -Data P1
6 +Data 0 40 -Data 0
Installing options
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