HSG80 ACS Solution Software V8.6 for Windows NT and Windows 2000 Installation and Configuration Guide

1–8 HSG80 ACS Solution Software Version 8.6 for Windows NT and Windows 2000 Installation and
Configuration Guide
In multiple-bus failover mode, you can specify which units are normally serviced by a
specific controller of a controller pair. This process is called preferring or preferment.
Units can be preferred to one controller or the other by the PREFERRED_PATH switch of
the
ADD UNIT (or SET unit) command. For example, use the following command to prefer unit
D101 to “this controller”:
SET D101 PREFERRED_PATH=THIS_CONTROLLER
NOTE: This is an initial preference, which can be overridden by the hosts.
Keep the following points in mind when configuring controllers for multiple-bus failover:
■ Multiple-bus failover can compensate for a failure in any of the following:
❏ Controller
❏ Switch or hub
❏ Fibre Channel link
❏ Host Fibre Channel adapter
■ A host can redistribute the I/O load between the controllers
■ All hosts must have operating system software that supports multiple-bus failover
mode