>iptables -P INPUT DROP >iptables -A INPUT -p tcp --destination-port 53 -j ACCEPT >iptables -A INPUT -p udp --destination-port 53 -j ACCEPT "Think before you rule." If your NAMED makes a query to the outside world, its _DEFAULT configuration will NOT use_ 53 as source port, so --destination-port 53 cannot match. (Use -m state --state ESTABLISHED)
