Setting Up a Reverse Proxy with Nginx on AlmaLinux 9

As a software developer or system administrator, you might have to set up a reverse proxy to streamline your server architecture. You can do this by centralizing access to web applications, enhancing security, and enhancing load balancing. 

Nginx is a powerful and versatile web server that is often employed for this purpose. In this article, we will guide you through the process of setting up a reverse proxy with Nginx on AlmaLinux 9, a robust and open-source enterprise-level Linux distribution.

Installing Nginx

To begin, ensure that your system packages are up-to-date. Run the following command: 

sudo dnf update -y

Next, install Nginx:

sudo dnf install nginx -y

Once installed, start and enable the Nginx service to run on boot:

sudo systemctl start nginx
sudo systemctl enable nginx

Configuring Nginx as a Reverse Proxy

Your website’s Nginx configuration file should look like this:

sudo nano /etc/nginx/conf.d/your_domain.conf

Substitute ‘your_domain.com’ for your domain name and ‘backend_server_ip’ for the IP address of your backend server in the following server block:

server {
    listen 80;
    server_name your_domain.com;
    location / {
        proxy_pass http://backend_server_ip;
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }
}

Save and exit the file.

Check the Nginx configuration for syntax errors:

sudo nginx -t

If your configuration testing is successful, reload Nginx to apply the modification.

sudo systemctl reload nginx

Securing Your Reverse Proxy with SSL/TLS

To secure your reverse proxy, you can use Let’s Encrypt to obtain a free SSL certificate, you need to install the Certbot client and the Nginx plugin: 

sudo dnf install certbot python3-certbot-nginx -y

To obtain and install an SSL/TLS certificate, run Certbot:

sudo certbot --nginx -d your_domain.com

Follow the on-screen prompts to complete the process. Certbot will automatically update your Nginx configuration to use the acquired SSL/TLS certificate.