Running Devil Linux so iptables is version 1.2.11 Trying to setup rules that will only allow connections in on telnet, DNS, and DHCP Also the telnet rule should only allow connections that are destined for 10.0.0.1 So setting all initials chains to drop {$IPTABLES} -P INPUT DROP {$IPTABLES} -P OUTPUT DROP {$IPTABLES} -P FORWARD DROP $IPTABLES -A INPUT -p tcp -i eth1 -d 10.0.0.1 --dport 23 -m state --state NEW,ESTABLISHED -j ACCEPT Is it OK to do this on the INPUT? This box is also a router, will the iptables happen before any routing happens. I guess my question is one of order. When a packet comes in will it be handled by the iptables INPUT first? How can I safely allow outgoing packets? To allow DNS and DHCP in can I do something like $IPTABLES -A INPUT -p tcp -i eth1 --dport 53 -m state --state NEW,ESTABLISHED -j ACCEPT #DNS $IPTABLES -A INPUT -p tcp -i eth1 --dport 67 -m state --state NEW,ESTABLISHED -j ACCEPT #DHCP $IPTABLES -A INPUT -p tcp -i eth1 --dport 68 -m state --state NEW,ESTABLISHED -j ACCEPT #DHCP How can I allow these ports out? Thank you for your help! -Michael