Unbound
I installed unbound on april and added dns entries for rafael, leonardo, michelangelo, donatello, and april itself.
The base domain is sagroup.hackmanhattan.com.
I added a zone for hackmanhattan.com. I added a record for mk4-prusa.hackmanhattan.com as an experiment to see if it would resolve. It does.
I changed the DHCP configuration on HM's main and wireless routers to give out *april* as the default DNS server, with the main router as a secondary.
I added a record for the docker container leatherhead.sagroup.hackmanhattan.com. A route to leatherhead's virtual network was added to the main router.
I added a record for rackpower.hackmanhattan.com. This is the Smart_Power_Strip on the rack.
I added records for the iDRAC controllers on the server (idrac-donatello.sagroup.hackmanhattan.com.
I created /var/log/unbound.log and changed the owner and group to unbound:unbound. This eliminates an error on service startup.