ufw - uncomplicated firewall¶

well, still too complicated from time to time for me. so let's write it down. see also iptables - or check the ubuntu wiki

enable / disable ufw¶

ufw enable
ufw disable

manage rules¶

list rules¶

ufw status # simple list
ufw status numbered # numbered list, so you can also delete rules
ufw status verbose # some more info, no numbers

delete rules¶

ufw delete N # where N is the number from the list command above

allow application / port¶

ufw allow openssh
ufw allow 22
ufw allow from 1.2.3.4 to any port 22 # allow from 1.2.3.4 port 22
ufw allow from 1.2.3.4 to any port 22 proto tcp # allow from 1.2.3.4 port 22, tcp

deny application / port¶

ufw deny from 1.2.3.4