iptables cheat sheet

.profile

# show routing (with rule numbers per Chain fortable:"nat")
alias routing='sudo iptables -t nat -L -n -v --line-number'

# open 80 explicitly 
# sudo iptables -A INPUT -p tcp --dport 80 -j ACCEPT

# redirect 80 to 8080 
# iptables -t nat -A OUTPUT -o lo -p tcp --dport 80 -j REDIRECT --to-port 8080

# delete a rule (table:"nat", Chain:"OUTPUT" rule:1)
# sudo iptables -t nat -D OUTPUT 1