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

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SCSI jumpers
The option jumper block on the DASD (SCSI) backplane
defines the SCSI IDs for hot-swap drives. See the
illustration in “DASD backplane jumper block location” on
page 138 for the location of the option jumper block.
The following table summarizes the settings for the DASD
backplane SCSI option jumper block (J4).
The following table shows the SCSI IDs that you can use
for hot-swap drives.
Table 8. Backplane Option Jumper Block
Pins Description
1-2 (A0) Removing the jumper from these two pins
reverses the SCSI IDs on the backplane. For
the tower model, these two pins are
jumpered; for the rack model, the jumper
usually is removed.
3-4 (A1) Reserved. No jumper.
5-6 (A2) These pins are always jumpered.
Tower Addressing Rack (Reversed)
Addressing
J4
A2
A1
A0
J4
A2
A1
A0
Table 9. SCSI IDs for Hot-Swap Drives
J4 Pins 1-2 (A0) Bay
1 Bay
2 Bay
3 Bay
4 Bay
5
Jumpered (tower orientation) 0 1 2 3 4
Jumper removed, DASD enclosure
not rotated 4 3 2 1 0
Jumper removed, DASD enclosure
rotated for rack orientation 0 1 2 3 4
Notes: When the DASD enclosure on a tower model has been rotated
for rack-mount orientation and the jumper has been removed, the bays
correspond to the rack model illustration on page 64.
Netfinity 5000 - Type 8659
137