Township engineers ask what an L2 VNI versus an L3 VNI means in an EVPN-VXLAN control plane. Which distinction is correct?
Select an answer to reveal the explanation.
Short Explanation
L2 VNI is the bridged neighborhood where MACs hang out; L3 VNI is the routed hallway that lets subnets talk through IRB. Mixing those names up sends you troubleshooting the wrong door. Neither one is just a nickname for a loopback address family.
Full Explanation
In EVPN-VXLAN, Layer-2 VNIs correspond to bridge domains/overlay broadcast domains where MAC learning and intra-subnet bridging occur. Layer-3 VNIs are used for inter-subnet routing with IRB so traffic between tenant subnets can be routed in the fabric (subject to CRB/ERB architecture choices covered elsewhere). They are not underlay address-family labels, STP-only constructs, or spine-exclusive objects. Clear L2 versus L3 VNI roles are fundamental when reading EVPN control-plane state on Junos DC fabrics.