Here is an example to log new tcp connections (port 22):
-A INPUT -m state –state NEW -m tcp -p tcp –dport 22 -j LOG –log-prefix “New Connection: ” –log-level 4
Here is an example to log any tcp connections:
iptables -A INPUT -m state --state NEW -j LOG --log-prefix "New Connection: " iptables -A OUTPUT -m state --state NEW -j LOG --log-prefix "New Connection: "