Customer Use Case

High availability (HA) and load balancing among endpoints are crucial particularly where traffic volumes are very large. The rapid increase in virtualized applications has increased the volume of Media Access Control (MAC) addresses that the network must handle. For large service providers and enterprises, hundreds of thousands of MAC addresses can be supported across interconnected sites. If a node or link fails, the need to re-learn a high number of MAC addresses in the broadcast domain can slow network reconvergence, leading to data loss and slow application performance.

To ensure rapid recovery after a failure, Ethernet VPN (EVPN) provides HA mechanisms such as fast reconvergence and efficient signaling with remote devices. It also includes the ability to establish multihomed connections to endpoints, offering load balancing as well as greater resiliency and reliability against the potential failure of one connection or node. EVPN enables hosts to relocate within the same subnet without requiring renumbering.

In addition to standard EVPN HA techniques, Juniper’s EVPN implementation provides gateway redundancy by allowing the same gateway IP and MAC address to be configured on all EVPN provider edge (PE) devices. By adding both host and gateway MAC and IP address information in MAC routes, EVPN provides optimum forwarding for unicast and multicast traffic. When you configure the EVPN-Virtual Extensible LAN protocol (VXLAN) virtual gateway with the same IRB IP address and MAC address, the virtual gateway address configuration provides gateway redundancy for Layer 3 functionality and load balancing of intersubnet traffic over multiple active paths. Such a configuration enables Virtual Router Redundancy Protocol (VRRP)-like default gateway redundancy to protect against PE device failures.

EVPN overcomes the shortcomings of current technologies by providing integrated Layer 2/Layer 3 connectivity, native support for multihoming, MAC address mobility, and network resiliency between edge nodes. Additionally, Juniper has enhanced its EVPN implementation to further improve scalability, multihoming, and configuration flexibility while preserving standards-based interoperability.

This document describes how to configure the virtual gateway address for IRB interfaces as part of an EVPN-VXLAN deployment.