A municipal NOC captures leaf-to-spine fabric packets and sees a VNI field inside the VXLAN header. What data-plane role does that VNI play on the egress VTEP?
Select an answer to reveal the explanation.
Short Explanation
Think of the VNI like a shipping-container number on a city transit truck: the underlay only hauls the truck, but the warehouse door that opens is picked by that number. On decap, the VTEP uses the VNI to pick the right L2 bridge domain or L3 overlay context before it hands the frame to a local server. Without that binding, the payload has nowhere sensible to land.
Full Explanation
In the VXLAN data plane, the VNI in the VXLAN header identifies the overlay segment. After UDP/IP decapsulation, the egress VTEP maps that VNI to a configured bridge domain or L3 VNI/VRF context and then performs local L2 or L3 forwarding. Spines typically forward based on outer IP and do not interpret tenant VNIs for tenant bridging. Correct VNI-to-domain mapping is therefore essential for isolation and correct delivery on the municipal fabric.