Deployment Guide

9 Dell EMC Networking Virtualization Overlay with BGP EVPN
3 BGP EVPN VXLAN overview
EVPN is a control plane for VXLAN that is used to reduce flooding in the network and resolve scalability
concerns. EVPN uses multiprotocol BGP (MP-BGP) to exchange information between VXLAN tunnel
endpoints (VTEPs). EVPN was introduced in RFC 7432, and RFC 8365 describes VXLAN-based EVPN.
VXLAN-based EVPN is a next-generation VPN. It is intended to replace previous generation VPNs like Virtual
Private LAN Service (VPLS). Some of its key features are:
• Support for multi-tenancy
• Layer 2 and 3 integrated routing and bridging (IRB)
• Multi-homing
• Minimization of ARP propagation
• MAC mobility (simplified VM migration)
The primary use cases for EVPN are:
• Greatly expanding the potential number of Layer 2 domains
• Service provider multi-tenant hosting
• Data center interconnect (DCI)
Spine
Spine
VLT VLT
Server
Server
Server
Server
Gateway/
Firewall
VTEP
VNI A
VTEP
VTEP
VLT
Leaf Leaf Leaf Leaf
Leaf Leaf
VNI B
VNI C
Overlay networks
VNI A GW
VNI B GW
VNI A GW
VNI B GW
VNI A GW
VNI B GW
VNI C GW
VNI A Anycast gateway
VNI B Anycast gateway
VNI C Indirect gateway
Border Leafs
VNI C GW
BGP EVPN topology
This deployment guide demonstrates the following:
• Tunneling of Layer 2 overlay virtual networks through a physical Layer 3 leaf-spine underlay
network using VXLAN-based EVPN
• Decentralized inter-VXLAN routing via anycast gateways for VXLAN Network Identifier (VNI) A
and B
• Centralized routing for VNI C using an indirect gateway located on the external gateway/firewall