Simple iptables rules presets

iptables_rules

*filter

# Internal interfaces
-A INPUT -i lo -j ACCEPT
-A OUTPUT -o lo -j ACCEPT

#Allow all established traffic
-A INPUT -m state --state ESTABLISHED -j ACCEPT

#SSH
-A INPUT -p tcp -m tcp --dport 22 -j ACCEPT
-I INPUT -p tcp --dport 22 -i eth0 -m state --state NEW -m recent --set
-I INPUT -p tcp --dport 22 -i eth0 -m state --state NEW -m recent --update --seconds 60 --hitcount 5 -j DROP

#HTTP
-A INPUT -p tcp -m tcp --dport 80 -j ACCEPT
#HTTPS
-A INPUT -p tcp -m tcp --dport 443 -j ACCEPT

# smtp server
#-A INPUT -p tcp -m tcp --dport smtp -m state --state NEW,ESTABLISHED -j ACCEPT
#-A INPUT -p tcp -m tcp --sport auth -m state --state ESTABLISHED -j ACCEPT

#SNMP Monitoring, enable only for monitor server ip
-A INPUT -s 127.0.0.1 -p udp -m udp --dport 161 -j ACCEPT

#ICMP
-A INPUT -p icmp -j ACCEPT

#Drop everything not mentioned
-A INPUT -j DROP

COMMIT