Cisco Configuring EVPN VXLAN External Connectivity User Manual PDF (EN)

Information About EVPN VXLAN External Connectivity

Configuring EVPN VXLAN External Connectivity Restrictions for EVPN VXLAN External Connectivity, on page 1 Information About EVPN VXLAN External Connectivity, on page 1 How to Configure EVPN VXLAN External Connectivity, on page 6 Configuration Examples for EVPN VXLAN External Connectivity, on page 20 Restrictions for EVPN VXLAN External Connectivity • External connectivity with VPLS networks is supported only when bridging is the mode of interworking between the two domains. Integrated routing and bridging (IRB) is not supported between a BGP EVPN VXLAN fabric and a VPLS network. • External Connectivity with Layer 3 networks is supported only for IPv4 and IPv6 unicast traffic.

• The following EVPN VXLAN features are not supported on : • MPLS Layer 3 VPN Border Leaf Handoff • MPLS Layer 3 VPN Border Spine Handoff • VPLS over MPLS Border Leaf Handoff • VPLS over MPLS Border Spine Handoff • Interworking of Layer 3 TRM with MVPN Networks for IPv4 Traffic Information About EVPN VXLAN External Connectivity External connectivity allows the movement of Layer 2 and Layer 3 traffic between an EVPN VXLAN network and an external network. It also enables the EVPN VXLAN network to exchange routes with the externally connected network. Routes within an EVPN VXLAN network are already shared between all the VTEPs or leaf switches.

External connectivity uses the VTEPs on the periphery of the network to pass on these routes to an external Layer 2 or Layer 3 network. Similarly, the EVPN VXLAN network imports the reachability routes from the external network. External connectivity extends the Layer 2 or Layer 3 overlay network outside the VXLAN network. The process of extending a Layer 2 or Layer 3 network outside the EVPN VXLAN network is also known as handoff. Configuring EVPN VXLAN External Connectivity 1

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Implementation of Border Nodes for EVPN VXLAN External Connectivity

Implementation of Border Nodes for EVPN VXLAN External Connectivity Border nodes or border VTEPs are the devices through which you establish a connection between an EVPN VXLAN network and an external network. The border nodes sit on the periphery of the EVPN VXLAN network and remain a part of the BGP EVPN VXLAN fabric. To enable external connectivity, you can implement the border nodes of an EVPN VXLAN network as either border leaf or border spine switches. Connectivity Through a Border Leaf Switch Leaf switches deployed as border nodes support the required control plane and data plane functionalities.

Border leaf deployment ensures that the configuration on the spine switches is much simpler. Border leaf switches only allow communication between the external network and the VXLAN network, also known as north-south communication. A border leaf switch can also be multiple switches functioning as a single logical system with Cisco StackWise Virtual configured. Note The following figure shows border leaf external connectivity of an EVPN VXLAN network with external Layer 2 and Layer 3 networks: Configuring EVPN VXLAN External Connectivity Implementation of Border Nodes for EVPN VXLAN External Connectivity Configuring EVPN VXLAN External Connectivity 2

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Implementation of Border Nodes for EVPN VXLAN External Connectivity

Figure 1: EVPN VXLAN External Connectivity Through a Border Leaf Switch Connectivity Through a Border Spine Switch Deploying spine switches as border nodes provides the advantage of optimizing the north-south communication with external resources. At the same time, border spine deployment allows the spine switches to support VXLAN control and data plane functionality. Border spine switches allow both north-south communication and east-west communication. East-west communication represents the communication within the nodes of the EVPN VXLAN network. The following figure shows border spine external connectivity of an EVPN VXLAN network with external Layer 2 and Layer 3 networks.:

Configuring EVPN VXLAN External Connectivity Implementation of Border Nodes for EVPN VXLAN External Connectivity Configuring EVPN VXLAN External Connectivity 3

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External Connectivity with Layer 3 Networks

Figure 2: EVPN VXLAN External Connectivity Through a Border Spine Switch External Connectivity with Layer 3 Networks Layer 3 external connectivity or handoff is established by connecting the border nodes of a BGP EVPN VXLAN fabric with an edge router from the external Layer 3 network. The border node acts as a VTEP to perform VXLAN encapsulation and decapsulation, but it also routes the traffic towards the edge routing device. The VXLAN-facing interface on the external Layer 3 network can be a switch virtual interface (SVI), or a Layer 3 interface, or a Layer 3 subinterface. You can use Layer 3 external connectivity to achieve any of the following:

• Extend the logical isolation between VRFs or VLANs within the EVPN VXLAN network into the externally routed network. The external routed network can be a traditional non-VXLAN campus network, a datacenter, or a WAN. • Provide shared access within the EVPN VXLAN network to a common external service such as the internet. BGP EVPN VXLAN fabric supports Layer 3 external connectivity with VRF-Lite and MPLS Layer 3 VPN networks. Configuring EVPN VXLAN External Connectivity External Connectivity with Layer 3 Networks Configuring EVPN VXLAN External Connectivity 4

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