How to Setup OpenVPN Server on Ubuntu 22.04

“A Virtual Private Network or VPN allows you to extend a private network across public networks. It enhances your online security; for example, if you are at a hotel and you are using the hotel’s internet connection for your business, there is a high chance that your data may be breached. VPN connections are private and encrypted, which prevents unauthenticated access to your connection. Today in this tutorial, we will go through all the steps required to set up OpenVPN Server on Ubuntu 22.04.”

OpenVPN

OpenVPN is an open-source application that is mainly used to access remote websites, create secure connections, and enhance security by using encryption, authentication, and of course, certification using the OpenSSL library. We will now set up OpenVPN on Ubuntu 22.04.

Step 1: Update the System Packages

sudo apt-get update && sudo apt-get upgrade

And it will automatically update your system’s packages.

Step 2: Install OpenVPN

sudo apt -y install openvpn

Now you have to wait a while, and once it is done, you can move to step 3.

Step 3: Generate a Static Key to Use for VPN Tunnel Encryption and Start the VPN Server

openvpn --genkey --secret static-OpenVPN.key

sudo openvpn --dev tun --ifconfig 172.16.0.1 172.16.0.2 --cipher AES-256-CBC --secret static-OpenVPN.key &

Note: You may have noticed the “&” at the end of the command above, and it is there to help you background the OpenVPN process so that you don’t have to keep the terminal open.

Step 4: Verify if You are Going True

Just enter the following command, and you will tun0 with an IP address of 172.16.0.1

ip a show tun0

The output would be like this

Now we have to verify if the UDP port 1194 is open for connections using the following command

netstat -anu | grep 1194

And this would generate output like this

Step 5: Configure Firewall

Use the following command to configure the firewall

$ sudo ufw allow from any to any port 1194 proto udp

And you will see the following output

The OpenVPN server is now capable of receiving incoming connections.

Now how are you going to connect the OpenVPN server from a remote client? Well, you have to go through the following steps.

Step 1: Install OpenVPN

sudo apt -y install openvpn

Step 2: Transfer the static-OpenVPN Key File From the OpenVPN Server to the Client

First, we have to transfer the file from the server to the client using a secure method of your choice, but we will use the SCP command like this

scp ubuntuser@linuxhint:/home/ubuntuser/static-OpenVPN.key

Note: this command needs to be issued from the client side, and do use your username.

Step 3: Establishing a VPN Tunnel to the Server

Using the following command, we will be able to establish a VPN tunnel to the server, but you do need to change the IP address according to the server you are connecting to

$ sudo openvpn --remote YOUR-OPENVPN-SERVER-IP-OR-HOST --dev tun --ifconfig 172.16.0.1 172.16.0.2 --cipher AES-256-CBC --secret static-OpenVPN.key &

Did you notice the cipher AES-256-CBC? Well, that is the most secure encrypting and decrypting the string of data.

Step 4: Testing if the Connection was Successful

If you are done with step 3, then you should be able to see the following message if the connection was successful.

Now we will confirm the successful connection by pinging a host on the remote server using the following command

ping -c 1 172.16.0.1

We will see something like this but don’t worry if it is different on your side

Conclusion

In this tutorial, we’ve gone through all the steps required to receive incoming connections using OpenVPN, and we also learned how to connect to an OpenVPN server from a remote client on Ubuntu. If you face any error or problem, please contact us because we are always happy to help our community.