Dell EMC SmartFabric OS10 User Guide Release 10.5.0

BGP EVPN for VXLAN

Ethernet Virtual Private Network (EVPN) is a control plane for VXLAN that reduces flooding in the network and resolves scalability concerns. EVPN uses MP-BGP to exchange information between VTEPs. EVPN was introduced in RFC 7432 and is based on BGP MPLS-based VPNs. RFC 8365 describes VXLAN-based EVPN.

The MP-BGP EVPN control plane provides protocol-based remote VTEP discovery, and MAC and ARP learning. This configuration reduces flooding related to L2 unknown unicast traffic. The distribution of host MAC and IP reachability information supports virtual machine (VM) mobility and scalable VXLAN overlay network designs.

The BGP EVPN protocol groups MAC addresses and ARP/neighbor addresses under EVPN instances (EVIs) to exchange them between VTEPs. In OS10, each EVI is associated with a VXLAN VNI in 1:1 mapping.

Benefits of a BGP EVPN-based VXLAN

• Eliminates the flood-and-learn method of VTEP discovery by enabling control-plane learning of end-host L2 and L3 reachability information.
• Minimizes network flooding of unknown unicast and broadcast traffic through EVPN-based MAC and IP route advertisements on local VTEPs.
• Provides support for host mobility.