SERVER PLUS INSIGHTS
BGP EVPN Anycast Gateway Design on Cisco Nexus
Unlike a stacked campus switch, a Nexus data-center vPC pair does not become one logical L3 gateway. BGP EVPN Anycast Gateway provides the same gateway address and MAC at both leaf switches while preserving an EVPN fabric design.
2026-07-11 · Server Plus
Unlike a stacked campus switch, a Nexus data-center vPC pair does not become one logical L3 gateway. BGP EVPN Anycast Gateway provides the same gateway address and MAC at both leaf switches while preserving an EVPN fabric design.
The gateway challenge in a vPC leaf pair
Traditional stackable switches can expose one logical control plane and gateway configuration. In a data-center fabric, two independent Nexus leaf switches run vPC but do not support stacking as one switch. Gateway high availability must therefore be designed for the distributed fabric.
Anycast Gateway design
Both leaf switches use the same virtual gateway MAC and the same SVI gateway address for the VLAN. Hosts retain one default gateway while either leaf can route locally, reducing dependency on first-hop redundancy protocols for each VLAN.
Fabric and routing role
The vPC leaf pair connects upstream through port channels to Nexus 9336C spine switches. BGP EVPN distributes endpoint reachability and VNI information, while OSPF can advertise SVI and loopback reachability toward upstream ASR or Juniper MX routing.
Operational checks
Confirm feature enablement, VNI mapping, NVE status, BGP EVPN control plane, vPC consistency, SVI Anycast Gateway mode, and upstream routing advertisements before placing tenant traffic in service.
FAQ
Does vPC itself provide a shared L3 gateway?
No. vPC provides multi-chassis Layer 2 port-channel behavior. Anycast Gateway provides the distributed default-gateway behavior in an EVPN fabric.
Why use OSPF toward upstream routers?
OSPF can advertise the required SVI and loopback reachability to upstream ASR or Juniper MX routers as part of the routed fabric design.