I currently have a Linux box as my gateway running Debian 10 Buster.
This machine runs an unbound DNS server that I use to re-route DNS requests to different servers depending on what host is being looked up mainly for things like Netflix/Hulu, etc. I have persistent iptable rules in place to force all port 53 traffic to the gateway box and it works quite well.
The iptable rules are here:
*filter :INPUT ACCEPT [0:0] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [0:0] COMMIT # Completed on Sun May 24 09:13:42 2020 *nat -A POSTROUTING -o wan0.10 -j MASQUERADE # -A POSTROUTING -o internet -j MASQUERADE -i lan0 -A PREROUTING -p udp -m udp --dport 53 -j DNAT --to-destination 10.1.1.1:53 -i lan0 -A PREROUTING -p tcp -m tcp --dport 53 -j DNAT --to-destination 10.1.1.1:53 -i lan1 -A PREROUTING -p udp -m udp --dport 53 -j DNAT --to-destination 10.1.1.1:53 -i lan1 -A PREROUTING -p tcp -m tcp --dport 53 -j DNAT --to-destination 10.1.1.1:53 -A PREROUTING -i wan0.10 -p tcp --dport 31346 -j DNAT --to 10.1.1.120:31346 COMMIT *filter -A INPUT -i lo -j ACCEPT # SSH always working -A INPUT -i lan0 -p tcp -m tcp --dport 22 -j ACCEPT -A INPUT -i lan1 -p tcp -m tcp --dport 22 -j ACCEPT # allow traffic -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT -A INPUT -p tcp -m tcp --dport 80 -j ACCEPT -A INPUT -p tcp -m tcp --dport 443 -j ACCEPT -A INPUT -i wan0.10 -j DROP COMMIT
My problem is I have one server on the LAN that I would like to bypass these rules and have access to pure DNS.
How would I go about overriding these rules for a single host on the network and also are rules in a first come first serve basis e.g. later rules override previous ones?