Best way to block manual dns changes on devices

[tattoomees]

Hi Is there a way control manually configured dns settings on devices , the adblock home works perfect but if i configure my  laptop to use google dns instead opensense it passes all dns filtering.

[CJ]

You have to implement firewall rules to block any DNS requests to servers other than your own.

I talk about it in part two of the blog post I did for DNS security and ad blocking.

https://www.cjross.net/dns-security-and-adblock-with-opnsense-part-2/

[tattoomees]

Perfect it works like a charm :)