By using a forwarder, you can manage name resolution for names that are outside your network, such as names on the Internet or names in other forests or domains.
Read about forwarders.
Understanding Forwarders
Plan how you will deploy forwarders in your network.
Using Forwarders
Configure the firewall that your network uses to allow only one Domain Name System (DNS) server to communicate with the Internet.
Configure other servers to use this DNS server as a forwarder.
Configure a DNS Server to Use Forwarders