Hi, I have Linux machine with single Network interface. I want to block all the tcp,udp and icmp port's other then 22,23,24 and 80. Can you verify the following script? IPTABLES=/sbin/iptables $IPTABLES -P INPUT DROP $IPTABLES -P OUTPUT DROP $IPTABLES -P FORWARD DROP $IPTABLES -A INPUT -p tcp -m multiport --destination-port 22,23,24,80 -j ACCEPT $IPTABLES -A INPUT -p udp -m multiport --destination-port 22,23,24,80 -j ACCEPT What port should I block for icmp protocol? -SR