UFW (default firewall on Ubuntu)

This note was created on 2023-08-07
This note was last edited on 2023-08-07

UFW (uncomplicated firewall) is a firewall configuration tool that runs on top of iptables, included by default within Ubuntu distributions.

=== Usage ===

Check if enabled:
# ufw status

Verbose status:
# ufw status verbose

Numbered status:
# ufw status numbered

Enable or disable UFW:
# ufw enable
# ufw disable

List available applications:
# ufw app list

Allow SSH:
# ufw allow OpenSSH

Open specific port:
# ufw allow 2323

Enable application profile:
# ufw allow “OpenSSH”

Block outgoing connection to port:
# ufw deny out 25

Delete rule:
# ufw delete allow 2323

Delete rule by number (see "Numbered status"):
# ufw delete 4

Block IP address:
# ufw deny from 200.0.323.130

Block subnet:
# ufw deny from 200.0.323.0/24

Allow access from IP address:
# ufw allow from 200.0.323.135