Specifications

2–6 Controller and Host Concepts
Shared Port IDs
Figure 2–3 shows one example of a Fibre Channel Switched Fabric (FC-SW)
configuration in transparent failover mode. In this configuration, the active port
attaches to a FC-SW node. The standby port on each controller will assume the
worldwide name if the active port fails, so that the standby port will be able to give
host access to the units.
Figure 2–3. Example of Host Port Shared IDs in Transparent Failover
The port IDs are shared between ports so that when a controller loses communication
and becomes unresponsive, the surviving controller seamlessly assumes the
unresponsive controller’s function. LUNs are distributed between ports as follows:
■ LUNs 0–99, port 1
■ LUNs 100–199, port 2
CXO6861A
Host
port 1
active
Controller A
Host
port 2
active
Controller B
FC-SW
FC-SW
Host
port 2
standby
Host
port 1
standby