UFW Quickstart Guide

UFW is the default firewall configuration tool for Ubuntu. This quickstart guide outlines several useful commands and techniques to assist debugging UFW.

Enable UFW

Enable UFW with the default set of rules:

$ sudo ufw enable

View status

Check the status of the server firewall with sudo ufw status. You may see one of these results:

UFW is not installed

$ sudo ufw status
ufw: command not found

UFW is installed, but not configured

$ sudo ufw status
Status: inactive

UFW is running

The firewall rules in force are displayed.

$ sudo ufw status verbose
Status: active

To                         Action      From
--                         ------      ----
22                         ALLOW       Anywhere
22 (v6)                    ALLOW       Anywhere (v6)

Disable UFW

$ sudo ufw disable

Reset UFW to default

$ sudo ufw reset

Example: Allow SSH, deny all other

A trivial example that blocks all inbound traffic except SSH (port 22).

$ sudo ufw default deny incoming
$ sudo ufw default allow outgoing
$ sudo ufw allow ssh

More Information

For more information, see our UFW documentation or the UFW man page.