Ops notices outer IP headers between civic leaves use loopback addresses as tunnel endpoints. What do those addresses represent in the VXLAN data plane?
Select an answer to reveal the explanation.
Short Explanation
Those leaf loopbacks in the outer header are the VTEP identities—the tunnel doorways—not the tenant VM addresses and not STP bridge IDs in disguise. They need to be reachable across the underlay so VXLAN packets can show up at the far leaf. Link-local-only would not get you across a Clos fabric.
Full Explanation
VTEP IP addresses are the outer tunnel endpoints used in VXLAN encapsulation. Leaf loopbacks are commonly used so VTEP identity remains stable independent of link failures. Underlay routing must reach those VTEP addresses across the fabric. Outer headers do not carry tenant VM IPs as the VXLAN tunnel endpoints, nor do they encode STP bridge IDs. Verifying loopback advertisement and reachability is a standard VXLAN data-plane prerequisite.