docker-dhcp-server/data/bind/zones/internal/db.site1.example.com

$TTL  10m
;$ORIGIN site1.example.com.
@  1D  IN  SOA ns1.example.com. hostmaster.example.com. (
            2002022401 ; serial
            3H ; refresh
            15 ; retry
            1w ; expire
            3h ; nxdomain ttl
           )
        IN  NS     ns1.example.com.
site1   IN  A      42.42.42.42
serv1   IN  A      10.15.0.1
serv2   IN  A      10.15.0.2