HSG80 ACS Solution Software Version 8.7 for Compaq Tru64 UNIX Installation and Configuration Guide

Table Of Contents
Planning a Subsystem
1–7HSG80 ACS Solution Software Version 8.7 for Compaq Tru64 UNIX Installation and
Configuration Guide
1–7
Figure 1–6: Transparent failoverafter failover from controller B to controller A
Multiple-Bus Failover Mode
Multiple-bus failover mode has the following characteristics:
Host controls the failover process by moving the units from one controller to
another
All units (0 through 199) are visible at all host ports
Each host has two or more paths to the units
CXO7035A
Host
port 1
active
Host
port 2
active
D100 D101 D120D0 D1
Host 1
Switch or hub
Host 2
Switch or hub
Host 3
Host
port 1
not
available
Controller A
Controller B
not available
Host
port 2
not
available