How to configure nslookup/dig to resolve hostnames mentioned in /etc/hosts?

Issue

• How to configure nslookup/dig to resolve hostnames mentioned in /etc/hosts?

• DNS Server is hosted on the outside network. Internal DNS Server is hosted using BIND within the network to resolve the internal clients. Clients can resolve the Outer DNS when gave a outside nameserver, but cant resolve internal DNS Client. When internal clients are configured to use Internal DNS Server, they cant resolve outer subdomains. For example:

  • example.com hosted on outer network giving resolving for www.example.com & mail.example.com
  • host1.example.com & host2.example.com are hosted within the internal network.