Is there anyway to force computers to use a specific DNS? Even if a computer has a defined a DNS address that I don't want, all of its DNS traffic from it will be resolved using the specific DNS. I guess I'm trying to say is there a way to emulate a proxy so to speak with out making one.
The whole reason why I'm doing this is that I use OpenDNS for web filtering but the only thing that you need to do to bypass that is just type in a different DNS server in Windows.
One idea could be to somehow use a Captive portal to stop web traffic until the user has the correct DNS server. I don't know how to use a captive portal to check a DNS setting though...
Any ideas would be great. Thanks.