Compaq AA-RHGWB-TE - Manual (Page 119)

• The units are divided between an HSG80 port 1 and port 2.
• If there are dual-redundant HSG80 controllers, controller A port 1 and
controller B port 2 are normally active; controller A port 1 and controller
B port 1 are normally passive.
• If one controller fails, the other controller takes control and both its
ports are active.
Figure 6–4 shows a typical Fibre Channel cluster configuration using
transparent failover mode.
Figure 6–4: Fibre Channel Single Switch Transparent Failover
Configuration
KGPSA
DSGGA
KGPSA
RA8000/
ESA12000
Member
System
2
Member
System
1
ZK-1531U-AI
HSG80 HSG80
In transparent failover, units D00 through D99 are accessed through port 1
of both controllers. Units D100 through D199 are accessed through port 2 of
both HSG80 controllers (with the limit of a total of 128 storage units).
You cannot achieve a no-single-poit-of-failure (NSPOF) configuration using
transparent failover. The host cannot initiate failover, and if you lose a host
bus adapter, switch, or a cable, you lose the units behind at least one port.
Using Fibre Channel Storage 6–9