How to Enable OpenSSH Server on Ubuntu Linux- A Step-by-Step Guide

How to Enable OpenSSH Server on Ubuntu Linux- A Step-by-Step Guide

Table of contents

Ensuring secure and efficient remote access to servers is crucial for managing and maintaining systems. OpenSSH plays an important role in performing all of the above tasks. It ensures safe, effective remote access and encrypts the transmitted data, which helps protect sensitive information from being intercepted by malicious actors.

This guide will walk you through enabling the OpenSSH server on an Ubuntu Linux system. Whether you’re setting up a new server or configuring an existing one, you’ll learn how to install, configure, and verify the OpenSSH server to ensure secure and reliable remote access to your Ubuntu machine.

What is OpenSSH?

SSH stands for Secure shell. OpenSSH is a network protocol that allows you to connect to and manage computers remotely. It allows file transfer from your host computer to your remote computer and allows you to execute commands within a secure environment.

It is a remote management tool that allows you to run commands on another machine. OpenSSH was developed by the OpenBSD project. Due to its encrypted communication protocol, OpenSSH is one of the most secure network protocols for client-server architectures.

Steps

In this tutorial, I will be using Ubuntu 22.04 on WSL2

  1. Launch the Ubuntu terminal
  • Run the following commands to update your system

      sudo apt update && sudo apt upgrade
    

    After updating your system, enter the clear command to have a clear terminal.

  1. Check if OpenSSH is installed.
  • Run the following command to check if OpenSSH has already been installed. If installed, you will see the following output

      sudo apt list -a openssh-server
    

    If not installed, you can proceed with the following steps.

  1. Install the OpenSSH server using the command below

     sudo apt install openssh-server
    

  2. Configure the firewall rules for OpenSSH.

  • But first, check the status using this command

      sudo ufw status
    

    If inactive, enable it using this command

      sudo ufw enable
    
    💡
    Ubuntu uses the Uncomplicated Firewall(UFW) to manage firewall rules.
  • Next, allow inbound SSH connection by enabling a firewall rule with this command.

      sudo ufw allow ssh
    

  1. Start and enable SSH service.
  • To start SSH, enter this command

      sudo systemctl start ssh
    
  • To enable SSH, enter this command

      sudo systemctl enable ssh
    

  1. Check the server status.

    After enabling SSH, you must ensure the server is actively running on your system. To check, enter the following command.

     sudo systemctl status ssh
    

    The image below shows SSH is running on my system

  2. Open the SSH configuration file to complete the setup

  • On your terminal, run this command

      sudo nano /etc/ssh/sshd_config
    

    You can edit the config file to suit your taste.

  • Activate the port by deleting the # symbol. The default port is 22. You can also change the port number to your preferred number. Do the same for the ListenAddress 0.0.0.0 and Password authentication.

  1. Restart and check the status of the SSH service using this command

     sudo systemctl restart ssh && sudo systemctl status ssh
    

  2. Connect and Configure network access.

  • The final step is to log in to your Ubuntu server via SSH using its IP address. To get the IP address of your machine, run this command

      ip addr
    

  • Next, copy the IP address and run this command to establish the connection

       ssh username@your_ubuntu_ipaddr
    

    You will be asked if you are sure you want to continue connecting. Type yes

    Congratulations! You have successfully enabled SSH. As you can see, it is a straightforward process.

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