How to setup Server with Ubuntu 22.04?

Hey nerds,

In this article, we will walk through the process of setting up an Ubuntu 22.04 server. As a computer science student, it's important to understand the technical aspects while keeping the instructions straightforward. Let's dive in!

Step 1: Logging into the Server

For Linux Users:

Open a terminal and use the following command to log in to your server:

ssh -i ssh_key abhishek@<server_ip_address>

For Windows Users:

Download and install Putty on your Windows PC.
Launch Putty and enter the following details:
- Hostname: <username>@<server_ip_address>
- Navigate to SSH > Auth and click "Browse" to select the SSH Private Key.
Click "Open" to establish the SSH connection.

Congratulations! You have successfully logged into your server.

Step 2: Creating a New User

To create a new user, follow these steps:

Run the command:
```
 sudo adduser <username>
```
Replace <username> with the desired username for the new user.
Grant administrative privileges to the new user:
```
 usermod -aG sudo <username>
```

Great! You have created a new user with administrative privileges.

Step 3: Setting Up the Firewall

Now, let's set up a firewall to enhance server security:

Check the available application profiles:
```
 ufw app list
```

Allow OpenSSH, HTTP, and HTTPS traffic:

 ufw allow OpenSSH
 ufw allow http
 ufw allow https

Enable the firewall:
```
 ufw enable
```

Verify the firewall status:

 ufw status

If the output matches the following, your firewall is correctly configured:

 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)

Step 4: Setting Up SSH Key in Ubuntu Server

To set up SSH key-based authentication, follow these steps:

Create a new SSH key pair using ssh-keygen:

```
    ssh-keygen
```
This generates two files: the public key (.pub extension) and the private key (no extension).
Switch to the new user:
```
 su - <username>
```

Create the necessary directory structure for SSH:

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

Open the authorized_keys file:
```
 nano ~/.ssh/authorized_keys
```
Copy and paste the content of the .pub file into the authorized_keys file and save it (CTRL+S).

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

Fantastic! You have successfully set up SSH key-based authentication.

Conclusion: By following this technical yet straightforward guide, you have now set up an Ubuntu 22.04 server, created a new user with administrative privileges, configured a firewall, and enabled SSH key-based authentication.

Happy exploring and learning on your new server!