I run the ISC DHCP Server service on my local network in a reduntant configuration for assigning addresses dynamically. This page documents this usage.
Both servers are configured as failover peers. beowulf.in.quay.net is the primary, grendel.in.quay.net is secondary.
To ensure that we don't try to serve IPv6 addresses (and to work around an issue with the systemd unit), configure the interface explictly in /etc/default/isc-dhcp-server by adding an interface to the following variable that is empty by default:
INTERFACESv4="eth0"
Provided that IPv6 is disabled via sysctl then this will work correctly.
Static leases are stored in a separate static-leases.conf file that should be updated on both servers using Ansible.
Start the service thusly:
systemctl enable isc-dhcp-server systemctl start isc-dhcp-server