Arp resolves ip addresses (to mac address) for any hosts and router interfaces on the internet.

I also could use the auto scrip feature in VRRP to turn on and off DHCP servers when master/slave state changes but once again that is over my. I was thinking using the DHCP failover options but that is well over my head. I was wondering if there is a better way to change my DHCP settings other then moving to a /22 and keeping the same strategy.