Virtual Extensible Local Area Network (VXLAN) is an L2 overlay scheme on top of an L3 network, also described as an L2 in L3 tunnel. It runs over the existing networks and provides the means to stretch the L2 network. As a standardized overlay technology, multiple vendors have adopted VXLAN as a datacenter solution to provide scalability and allow layer 2 across IP network. MP-BPG EVPN as the VXLAN control plane protocol provides a robust scalable solution to overcome the limitation in VXLAN flood and learn mode. Only VMs within the same VXLAN segment can communicate with each other. Each VXLAN segment is identified by a 24 bit segment ID called VXLAN Network Identifier (VNI). This helps to overcome the 4094 VLAN scale limitation and enables extension to 224 segments. VXLAN uses BGP as its control plane for Overlay. It makes its forwarding decisions at VTEPs (Virtual tunnel end points) for L2 and L3. Forwarding happens based on MAC or IP learned via the control plane (MP-BGP EVPN) . VXLAN uses IGP, PIM and BGP as its underlay in the fabric.
This lab introduces students to the industry standard MP-BGP EVPN and Cisco implementation of VXLAN on NXOSv. Student will use virtual Nexus switches to implement MP-BGP EVPN VXLAN control plane. Upon completion of this lab, users will able to
• Manually configure BGP EVPN in a standard Spine-Leaf topology
• Use command line to verify VXLAN/BGP EVPN.