tools

Overview

UFW (Uncomplicated Firewall) is a simplified front-end for managing Linux firewall rules. Built on top of iptables and Netfilter, it abstracts complex rule syntax into straightforward commands — trading granular control for ease of use. Ideal for quick firewall configuration on Linux servers and desktops.

Target / Context

Linux systems requiring firewall configuration. Sits in a hierarchy of Linux firewall tools — from most complex to simplest: Netfilter → iptables → UFW → Pre-defined rules.

Installation

ℹ︎Installation Commands: 
sudo apt install ufw

Basic Usage

ℹ︎Basic Usage: 
sudo ufw status
sudo ufw enable
sudo ufw disable

Flags & Options

ℹ︎Flags & Options:
FlagDescriptionExample
statusCheck current firewall statussudo ufw status
status numberedShow all active rules with index numberssudo ufw status numbered
enableEnable the firewallsudo ufw enable
disableDisable the firewallsudo ufw disable
allowAllow traffic on a port or servicesudo ufw allow 80/tcp
denyDeny traffic on a port or servicesudo ufw deny 22/tcp
deleteDelete a rule by index numbersudo ufw delete 2
defaultSet default policy for traffic directionsudo ufw default allow outgoing

Common Use Cases

Check Firewall Status

ℹ︎Commands: 
sudo ufw status
sudo ufw status numbered

Allow or Deny Traffic

ℹ︎Commands: 
sudo ufw allow 80/tcp
sudo ufw deny 22/tcp
sudo ufw default allow outgoing
sudo ufw default deny incoming

Manage Existing Rules

ℹ︎Commands: 
sudo ufw status numbered
sudo ufw delete 2

References / Images