Which of these is a key CX EVPN VXLAN capability?

A key capability of EVPN VXLAN on Aruba CX switches is ARP suppression. The BGP EVPN control plane distributes host MAC and IP address information (MAC-IP bindings) among all VTEPs in the fabric. When a VTEP receives an ARP request from a local host, it can intercept the request and, if it has the binding information for the target IP, reply on behalf of the remote host. This prevents the ARP request (a broadcast) from being flooded across the entire VXLAN overlay network. This significantly reduces BUM (Broadcast, Unknown Unicast, and Multicast) traffic, leading to a more efficient and scalable network.

A. Aruba CX switches support Symmetric Integrated Routing and Bridging (IRB), which is more scalable and efficient than the Asymmetric IRB model.
B. Aruba CX supports a distributed anycast gateway model where every VTEP can act as the default gateway, not only a centralized model.
D. EVPN VXLAN does not eliminate BUM traffic forwarding. It optimizes it, but necessary BUM traffic is still forwarded across the overlay, typically using ingress replication.

1. ArubaOS-CX 10.11 VXLAN Guide

Hewlett Packard Enterprise

(December 2022).

For Correct Answer (C): Page 10

Section "ARP suppression": "With EVPN

VTEPs can perform local ARP resolution and suppress ARP flooding over the VXLAN tunnels. When a VTEP receives an ARP request from a host

it checks for the MAC address of the destination IP address in its neighbor table. If a match is found

the VTEP responds with the MAC address."

For Incorrect Option (A): Page 11

Section "Symmetric IRB": "ArubaOS-CX switches support symmetric IRB where both ingress and egress VTEPs perform routing lookups."

For Incorrect Option (B): Page 11

Section "Distributed L3 gateways": "In a distributed L3 gateway model

the VTEPs also act as the default gateway for the hosts."

For Incorrect Option (D): Page 10

Section "BUM traffic handling": "BUM traffic from a host is sent by the ingress VTEP to all remote VTEPs that are part of the same VNI. This is called ingress replication."