Proxy ARP (RFC 1027) is a technique by which a device on a given network answers the ARP queries for a network address that is not on that network. The Proxy ARP is aware of the location of the traffic's destination, and offers its own MAC address as destination. The captured traffic is then typically routed by the Proxy to the intended destination via another interface.

Use no ip proxy-arp to disable Proxy ARP, Proxy ARP is disabled by default.

The show arp command on the hosts shows the ARP table entries to reach different subnets. Host B is reachable from host A and the necessary configurations should be present. Ping Host A from Host B. The ARP table should have the router’s xe1 interface MAC address to reach Host A. Execute the below command at Host B:

Local Proxy ARP feature is used to enable local proxy support for ARP requests per interface level. Activation will make the router answer all ARP requests on configured subnet, even for clients that should not normally need routing. Local proxy ARP means that the traffic comes in and goes out the same interface.

The local proxy ARP feature allows responding to ARP requests for IP addresses within a subnet where normally no routing is required. With the local proxy ARP feature enabled, ARP responds to all ARP requests for IP addresses within the subnet and forwards all traffic between hosts in the subnet. Use this feature only on subnets where hosts are intentionally prevented from communicating directly.

The show arp command on hosts shows the arp table entries to reach different subnets. Ping from Host A to random destination ip with same network (20.20.0.7) and then Ping Host B from Host A.Host A ARP table should have Router’s xe1 interface MAC address to reach Host B. Execute the below command at Host A.