docker run -d --name ddns-grunt -p 53:53/tcp -p 53:53/udp samisdat/ddns
docker exec -it ddns-grunt grunt server:init --ns ns.example.com --domain dev.example.com
docker exec -it ddns-grunt grunt client:create
docker cp ddns-grunt:/ddns/client.tar .
tar xvf client.tar cd client ./do-nsupdate.sh
dig @localhost dev.example.org +short
dig dev.example.org +short