HP A3312A - Manual (Page 22)

Installation & Configuration
Setting SCSI ID Switches
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Installation
Setting SCSI ID Switches
CAUTION! Do not set SCSI ID switches A3, A4, B3, or B4 to ID 0. If their IDs are set to 0,
an over-current condition will occur during the power-on sequence and the power
module will shut down.
CAUTION! All storage modules and host bus adapters (HBAs) must have unique SCSI
IDs. If two or more devices have the same SCSI ID on the SCSI bus, the host will not
recognize those devices.
NOTE! SCSI ID 7 is normally reserved for the host bus adapter (HBA). SCSI IDs 8 through 15
are used only by fast/wide differential (DF) modules.
To set SCSI ID switches for the disk and tape modules:
1. Perform an ioscan (HP-UX) or sysgen (MPE-iX) to determine which SCSI IDs are already in use.
2. Locate the SCSI ID switch for the device (see Figure 10, items 3 through 6 and 9 through 12).
3. Set the SCSI ID switch to an ID number not in use by another device (see Figure 11 and Figure 12):
•
When setting SCSI IDs for 1-inch modules, use the SCSI ID switch that corresponds to the slot
number occupied by the module. For example, if a disk module occupies slot A4, use SCSI ID
switch A4.
•
When setting SCSI IDs for 1.6-inch modules, use the SCSI ID switch that corresponds to the
lowest slot occupied by the module. For example, if a DDS tape module occupies slots A1 and
A2, use SCSI ID switch A1.