Active-active layer 3 default gateway

VSX aggregation switches can be configured with a shared virtual IP (VIP) and a shared virtual MAC address (VMAC) on the layer 3 VLAN interface.

The VIP/VMAC serves as the default gateway for the access layer. The two switches then share the router MAC and function as an active-active gateway for the IP subnet. The first VSX device that receives traffic from the access layer (based on the hashing algorithm over the LAG interface) routes it across to the other subnets.