Hi.
I'd like to force all the users to use a DNS service of my choice.
I know before login the users are allowed to access only DNSes specified in config, if UAMAnyDns is 0.
But after the user is logged in I found out that if it changes the DNS, service will work anyway.

Is it possible to block out this latest chance, that is using any dns once logged in?

I know I can do some iptables on the linux host, but what about DDWRT based solutions?

thanks