How to Setup a Server with Ubuntu 22.04

In this article, we’ll walk through the process of setting up an Ubuntu 22.04 server. Whether you’re a CS student or just getting started with Linux infrastructure, this guide keeps things practical and straightforward. Let’s dive in.

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Step 1: Logging into the Server

For Linux / macOS users, open a terminal and run:

ssh -i ssh_key abhishek@<server_ip_address>

For Windows users:

1. Download and install PuTTY
2. Launch PuTTY and enter:
   • Hostname: <username>@<server_ip_address>
   • Navigate to SSH → Auth, then click Browse to select your SSH private key
3. Click Open to connect

You’re in. 🎉

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Step 2: Creating a New User

Running everything as root is a bad habit. Create a dedicated user instead:

sudo adduser <username>

Replace <username> with whatever you want. Then grant sudo privileges:

sudo usermod -aG sudo <username>

Your new user can now run admin commands with sudo.

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Step 3: Setting Up the Firewall

Ubuntu ships with UFW (Uncomplicated Firewall). Let’s use it.

Check what application profiles are available:

ufw app list

Allow the traffic you actually need:

ufw allow OpenSSH
ufw allow http
ufw allow https

Enable the firewall:

ufw enable

Verify it’s running correctly:

ufw status

Expected output:

Status: active

To                         Action      From
--                         ------      ----
OpenSSH                    ALLOW       Anywhere
80/tcp                     ALLOW       Anywhere
443                        ALLOW       Anywhere
OpenSSH (v6)               ALLOW       Anywhere (v6)
80/tcp (v6)                ALLOW       Anywhere (v6)
443 (v6)                   ALLOW       Anywhere (v6)

Always allow OpenSSH before enabling UFW, otherwise you’ll lock yourself out of the server.

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Step 4: Setting Up SSH Key Authentication

Password-based SSH is convenient but weak. Key-based auth is the right way to do it.

Generate a new SSH key pair (run this on your local machine, not the server):

ssh-keygen

This creates two files — a private key (no extension, keep this secret) and a public key (.pub — this goes on the server).

Switch to your new user on the server:

su - <username>

Set up the .ssh directory with correct permissions:

mkdir ~/.ssh
chmod 700 ~/.ssh
touch ~/.ssh/authorized_keys
chmod 600 ~/.ssh/authorized_keys

Open the authorized keys file:

nano ~/.ssh/authorized_keys

Paste the contents of your .pub file in here and save.

Now test logging in with the key:

ssh -i <privatekeyfile> <username>@<server_ip_address>

The permissions on ~/.ssh (700) and ~/.ssh/authorized_keys (600) are not optional — SSH will silently refuse to use your key if they’re wrong.

SSH key authentication is now enabled. 🎉

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Wrapping Up

By following this guide, you’ve:

• Logged into a fresh Ubuntu 22.04 server
• Created a non-root user with sudo privileges
• Configured UFW to allow only the traffic you need
• Set up SSH key-based authentication

This is the baseline setup for any server you’ll run. Everything else — Nginx, Docker, your apps — builds on top of this foundation.

Happy exploring 🚀