H-4
Compaq ProLiant CL380 User Guide
Compaq Confidential – Need to Know Required
Writer:
Marcello Frau
Project:
Compaq ProLiant CL380 User Guide
Comments:
Part Number:
118128-003
File Name:
n-apph SCSI ID Configurations.doc
Last Saved On:
8/28/00 4:55 PM
Server Node SCSI Adapters
The Compaq 64-Bit Dual Channel Wide Ultra2 SCSI Controller in each server
node must be configured with a unique SCSI ID. During the initial
configuration, this is done through the System Configuration Utility (as part of
SmartStart). The only valid SCSI IDs that may be used are 6 and 7, with each
server using a different ID. These are considered Initiator SCSI IDs.
Host Channel Connections
Each CR3500 Controller has two Host I/O Channels, numbered 0 and 1. These
are assigned Target SCSI IDs using the CR3500 Configuration Utility
(Controller Properties). Channel 0 is normally assigned to Target ID 2, and
Channel 1 is normally assigned to Target ID 3. There is no need to change
these, and you should leave them at the default settings of 2 and 3. Also, when
using two CR3500 Controllers, the Channel Target IDs for each port should be
the same on both controllers (for example, Channel 0 Target ID set to 2 on
both controllers, and Channel 1 Target ID set to 3 on both controllers).
So the Host Side SCSI Bus uses a total of four SCSI IDs. The SCSI adapters in
the server nodes use SCSI IDs 6 and 7, while the two Host I/O Channels on
the CR3500 Controllers use Target SCSI IDs 2 and 3. However, since it is
possible to have two CR3500 Controllers, and if each one uses SCSI IDs 2 and
3, won’t there be a conflict? The following section on Failover Modes will
explain how this is avoided.
Failover Modes
In addition to a single standalone controller, there are two Failover Modes
(Active/Active and Active/Passive) that can be configured when using dual
redundant CR3500 Controllers. The configuration of these Failover Modes
eliminates the possibility of SCSI ID conflicts at the Host I/O Channels.
When using a single standalone CR3500 Controller, there is no possibility of a
SCSI ID conflict. The SCSI adapters in the server nodes use SCSI IDs 6 and 7,
while the two Host I/O Channels on the single CR3500 Controller use Target
SCSI IDs 2 and 3.