A UCS Fabric Interconnects pair can be configured in a high availability cluster. In the cluster configuration, FIs create a primary secondary affiliation to control data traffic flow whereas the data plane forwards simultaneously on both Fabric Interconnects. This means cluster control traffic flow is controlled only by the primary node whereas network data can flow through both FIs under normal conditions. Fabric Interconnects are connected through dedicated Gigabit Ethernet UTP copper ports, which do not participate in the data plane. These interfaces are marked as L1 and L2. L1 of one Fabric Interconnect should be connected to the L1 of the other Fabric Interconnect and similarly L2 should be connected to L2 of the peer. These links carry cluster heartbeat traffic.
High availability configuration requires three IP addresses. Both Fabric Interconnects require an IP address...