We run multiple isc-dhcpd servers. They are all configured over omapi from our management-stations, and they are thus having the same ip->mac mappings, and are operating independently from each other.
Installation
To install a dhcp server, install the role "role::dhcp" and list its information in hiera so that the dashboard knows about it.
After installation it can be useful to go to one of the dashboard-machines and trigger a new DHCP sync so that the new dhcp server gets to know about all the leases.