I have media box in my network that hard coded to use specific DNS servers like Google DNS. But I want force this device to use my own DNS servers instead of hard coded DNS. Only way I think this is possible to mangle the DNS request coming from that media box IP to DNAT to my DNS server IP. but I'm not quite sure how do I put rule with mentioning source port and source ip at the same time
I use openwrt router with openwrt 15.0 chaos calmer on it.
iptables -t nat -A PREROUTING -p tcp --sport 53 -j DNAT --to-destination 192.168.1.153
Above query will do the job but it will mangle all the port 53 request. how can I specify this rule with IP address. or is there any other way to do it ?