Merges to the master branch trigger a git [post-receive](https://github.com/openstreetmap/chef/blob/master/cookbooks/dns/files/default/post-receive) which runs `make update` via a [script](https://github.com/openstreetmap/chef/blob/master/cookbooks/dns/templates/default/dns-update.erb), the DNS is then updated by dnscontrol.
Merges to the master branch trigger a git [post-receive](https://github.com/openstreetmap/chef/blob/master/cookbooks/dns/files/default/post-receive) which runs `make update` via a [script](https://github.com/openstreetmap/chef/blob/master/cookbooks/dns/templates/default/dns-update.erb), the DNS is then updated by dnscontrol.