How to Allow and Open Port on Ubuntu with UFW

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To open a port on Ubuntu, you’ll need to configure the default firewall, UFW (Uncomplicated Firewall). By default, UFW blocks all incoming connections. To allow traffic through a specific port, you must create a new firewall rule.

This guide will help you understand how to open a port on Ubuntu using UFW, whether you’re allowing access for a specific IP address, network range, or general traffic. Using simple command-line instructions, you’ll learn how to open any TCP or UDP port on Ubuntu securely while maintaining system protection. Follow this guide on how to check for currently open ports on Ubuntu Linux.

In this tutorial you will learn:

  • How to open port to any source
  • How to open port to specific IP address or subnet
  • How to open UDP port
  • How to open TCP port
Example of how to Open/Allow incoming firewall port 53 on Ubuntu 22.04 Jammy Jellyfish
Example of how to Open/Allow port 53 on Ubuntu
Software Requirements and Linux Command Line Conventions
Category Requirements, Conventions or Software Version Used
System Ubuntu 18.04, 20.04, 22.04. 24.04 and above
Software ufw
Other Privileged access to your Linux system as root or via the sudo command.
Conventions # – requires given linux commands to be executed with root privileges either directly as a root user or by use of sudo command
$ – requires given linux commands to be executed as a regular non-privileged user

How to Open/Allow incoming firewall port on Ubuntu examples


Check out the various examples below to learn how the syntax works for allowing ports, IP addresses, and subnets through the ufw firewall on Ubuntu 22.04. Note that you will need to execute the following commands with root permissions.

  1. Open incoming TCP port 53 to any source IP address: 
    $ sudo ufw allow from any to any port 53 proto tcp
  2. Open incoming TCP port 443 to only specific source IP address eg. 10.1.1.222: 
    $ sudo ufw allow from 10.1.1.222 to any port 443 proto tcp
  3. Open incoming UDP port 53 to source subnet eg. 10.1.1.0/8: 
    $ sudo ufw allow from 10.1.1.0/8 to any port 53 proto udp
  4. Open incoming TCP ports 20 and 21 from any source, such as when running FTP server: 
    $ sudo ufw allow from any to any port 20,21 proto tcp
  5. Open port for a specific web server such as Apache or Nginx execute the below Linux command: 
    $ sudo ufw allow in "Apache Full"
$ sudo ufw allow in "Nginx Full"
  6. Open port for a specific service such as SSH: 
    $ sudo ufw allow in ssh

Closing Thoughts

In this tutorial, we saw how to open/allow incoming traffic through the ufw firewall on Ubuntu Linux. This included allowing TCP or UDP, one port or multiple ports, and traffic from a specific IP address or subnet. Keep in mind that more complex configuration (such at NAT) of UFW is also possible, as you can see in our other tutorial: How to Install and Use UFW Firewall on Linux.


If you need to remove any of the added rules in the future, see our other tutorial on How to delete UFW firewall rules on Ubuntu Linux.

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