There are several approaches to configuring the Domain Name Service (DNS) to work in conjunction with the Eagle. One is to run your primary DNS server directly on the G Box, with appropriate configuration of the Generic Service Passer file to allow DNS packets to enter and exit the internal network. This may not be appropriate if you wish to conceal the hostnames and IP addresses of your internal machines, or in the case where the IP addresses of your internal machines are not unique.
An alternative is to create a dual-level DNS system, using one or more special root nameservers on machines in your internal network. We will refer to these as internal root nameservers. In such a configuration, internal client machines query the internal root nameserver first, followed by the one on the G Box. The latter is capable of querying true root nameservers on the outside network. The G Box nameserver does not exchange DNS zone records for the internal network with outside nameservers.
In either case, it is assumed that you are providing primary name service for your domain, rather than you relying on your Internet service provider for primary name service. Your provider can function as a secondary, off-site nameserver, to meet Internet off-site nameserver requirements.