I have set up a linux (red hat 9) box as my main internet router. I am also running a DNS server on it. What are the rules i have to implement to allow DNS queries through the firewall from outside so that the outside world can see my domains?
You have to fire this command on Linux
/sbin/iptables -I INPUT -p udp --dport 53 -j ACCEPT
read out man pages of Linux firewall "iptables". One of very good document is "Netfilter HOW-To".