Hi Ganapathi,
ARP flooding can occur for the initial ARP request to a silent host in the network. The VTEPs in the network don’t see any traffic from the silent host until another host sends an ARP request for its IP address, and an ARP response is sent back. After the local VTEP learns about the MAC and IP addresses of the silent host, the information is distributed through the MP-BGP EVPN control plane to all other VTEPs. Any subsequent ARP requests do not need to be flooded.
Most end hosts send GARP or RARP requests to announce themselves to the network immediately after they come online, the local VTEP immediately has the opportunity to learn their MAC and IP addresses and distribute this information to other VTEPs through the MP-BGP EVPN control plane. Therefore, most active IP hosts in VXLAN EVPN should be learned by the VTEPs either through local learning or control-plane-based remote learning. As a result, ARP suppression reduces the network flooding caused by host ARP learning behavior.
Thanks,
Shivakumar Hulipalled