Layer 3 forwarding

EVPN uses either Centralized L3 gateway or Distributed L3 gateways to provide Layer 3 forwarding services for hosts in VXLANs.

  • Centralized L3 gateway第三层:使用一个VTEP提供转发VXLANs. Typically, the gateway-collocated VTEP connects to other VTEPs and the external network.

  • Distributed L3 gateway: Deploys one EVPN gateway on each VTEP to provide optimized Layer 3 forwarding for directly connected hosts.

In either design, the gateways use virtual Layer 3 interfaces as gateway interfaces for VXLANs. An AOS-CX switch cannot participate in both Centralized L3 gateway and Distributed L3 gateway topologies at the same time.