About SCSI IDs

The firmware suggested default for the A7173A adapter SCSI ID is 7.

You must assign a separate SCSI ID (0 through 15 for a 16-bit SCSI bus) to the A7173A adapter and to each SCSI device on the bus. The priority of a device on a SCSI bus is determined by the SCSI ID of the device. The order of SCSI ID priorities (from highest to lowest) is 7, 6, 5, 4, 3, 2, 1, 0, 15, 14, 13, 12, 11, 10, 9, and 8. A device with SCSI ID 7 has the highest priority, and one with SCSI ID 8 has the lowest.

HP recommends the A7173A adapter be assigned a higher priority than the other SCSI devices on the bus. SCSI ID 7 is the preset SCSI ID for the A7173A adapter, giving it the highest priority on the SCSI bus. Set each of the other SCSI devices on the bus to one of the remaining SCSI IDs.

In a multi-initiator HA (High Availability) configuration, multiple SCSI adapters are connected to the same SCSI bus. In a multi-initiator configuration, the SCSI adapter that carries the most traffic must be assigned a SCSI ID of 7 (highest priority). The SCSI ID of each of the remaining SCSI adapters on the bus should be set to the next highest priority remaining SCSI IDs (for example, 6, 5, 4, and so on) with the highest traffic adapters getting the highest priority SCSI IDs.

Setting SCSI IDs Offline

For HP 9000 systems, the Boot Console Handler (BCH) menus are used to set SCSI IDs offline. See “Using the BCH Menus on HP 9000 Systems”, for details.

For HP Integrity® systems, EFI is used to set SCSI IDs offline. See “Using the EFI Utility on HP Integrity Systems”, for details.

Setting SCSI IDs Online

The mptconfig command is used to display and set SCSI IDs online for all supported systems. See “Setting and Confirming SCSI Parameters Online”, for details.

	IMPORTANT: You must not have duplicate SCSI IDs on a SCSI bus; the system may hang or crash if you have duplicate SCSI IDs on the same bus.

	NOTE: Peripheral device SCSI IDs are typically determined automatically by the storage enclosure, or they may be set manually by a switch on the storage enclosure. See the documentation for each peripheral device to determine how to set its SCSI ID.