Interestingly enough, you don't need anything like this if you want HA-DHCP. The DHCP protocol actually allows you to have multiple DHCP servers answer the same

Interestingly enough, you don't need anything like this if you want HA-DHCP. The DHCP protocol actually allows you to have multiple DHCP servers answer the same request, and if they do it in the same way, then it won't cause any flip-flops. This usually works best when all the IP's are mapped to mac addresses statically, and usually you have a multi-master DHCP setup sharing a VIP for example. Happy hacking!