Overview of EVPN-VXLAN Interconnect through EVPN MPLS WAN Using Gateways

Overview of EVPN-VXLAN Data Center to Data Center Stitching Through an EVPN-MPLS Fabric

Configure seamless stitching between an EVPN-VXLAN data center, through an EVPN-MPLS fabric, to another EVPN-VXLAN data center, for interconnecting unicast and BUM traffic using WAN gateways with gateway-redundancy multihoming support. This feature is VLAN-based, and includes VLAN-aware bundle and VLAN bundle support using a VLAN list you configure. It is supported for interconnected MX platform bridge domains for both AFT-based and Ukern-based line cards.

This feature adds these parameters to the interconnect configuration statement:

See EVPN-VXLAN Gateway Interconnect Model Configuration Sample for a sample configuration.

Seamless stitching of EVPN-VXLAN to EVPN-MPLS is achieved by configuring both encapsulations, one for EVPN-VXLAN encapsulation going to the data center (DC) side, and EVPN-MPLS encapsulation on the WAN (DCI) side (under the interconnect stanza).

BUM traffic coming from the data center is flooded to DCI peers by pushing the IM label received from remote peers. BUM traffic coming from the WAN side is flooded to all DC VTEPs after popping the IM label.

One of the multihoming gateway nodes is elected as the designated forward (DF) based on I-ESI (interconnect and DF gateway will forward BUM traffic in either direction). To avoid the traffic duplication, the non-DF gateway drops the BUM traffic coming from the DCI side or the DC side. When there are multihoming CEs attached to gateway nodes, the current local bias filters handle split horizon functionality.

The unicast traffic from the DC side will be load balanced to remote DCI peers, and unicast traffic from the WAN is load balanced to the DC VTEPs within the data center.

EVPN-VXLAN Gateway Interconnect Model Configuration Sample

This sample configuration uses the interconnected-vlan-list statement and the encapsulation (protocols evpn) statement (with the mpls option) to define which VLANs to interconnect from the EVPN-VXLAN domain to the EVPN-MPLS domain.