$TTL 1D $ORIGIN us.example.com. @ IN SOA us.example.com. root.us.example.com. ( 2001030301 2H 1H 1W 1D ) IN NS ns1.us.example.com. ns1 IN A 192.168.1.10 mail IN MX 10 www.us.example.com. www IN A 192.168.1.11 A $INCLUDE Kus.example.com.+003+51297.key