Set up Nginx as Reverse Proxy on Ubuntu 20.04

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Here at Ibmi Media, we will look into how you can configure the NGINX web server as a reverse proxy on ubuntu server 20.04 LTS.

How does a Reverse Proxy work?

A reverse proxy is a server that is placed in front of one or more web servers, intercepting requests from clients. When the clients try to connect to the origin server of a website, those requests are intercepted by the reverse proxy server. The proxy server forwards these requests to the proxied server and receives responses from it to send them to the clients.

Benefits of Reverse Proxy includes:

Load balancing.
Global server load balancing (GSLB).
Caching content and web acceleration for improved performance.
More efficient and secure SSL encryption.
Protection from DDoS attacks and related security issues.

Pre-Requisites

Nginx web server installed on Ubuntu Server 20.04 LTS.
Website configured on Ubuntu Server 20.04 LTS.
SSH connection to remote machines (Nginx and Website).

For this purpose, We have used a website deployed on an ubuntu server 20.04 LTS. This will act as the main server or you can say proxied server. Nginx web server is deployed on another ubuntu server 20.04 LTS which We will configure as a reverse proxy in this tutorial. On our local machine, We have Linux Mint 20.02 installed from where We will form remote connections with:

Nginx Web Server's Virtual Machine's IP address: 10.11.120.2
Deployed Website's Virtual Machine's IP address: 10.11.120.3

To see how you can configure Nginx Server Block and Secure Nginx with Let’s Encrypt SSL on Rocky Linux 8 / CentOS 8, visit: https://linuxapt.com/blog/724-configure-nginx-server-block-and-secure-nginx-with-lets-encrypt-ssl-on-rocky-linux-8-centos-8

Steps to Set up Nginx as Reverse Proxy on Ubuntu 20.04

1. SSH to Nginx machine

The first step is to connect to the remote machine where Nginx is installed. We will configure Nginx as a reverse proxy on this machine. To do that, run the command below by adding the username and the IP of the machine where you have your Nginx deployed. In our case, it is nginx and 10.11.120.2:

$ ssh nginx@10.11.120.2

2. Disable pre-configured Nginx Virtual host

Next, unlink the default configuration of the Nginx Virtual host by running the command below:

$ unlink /etc/nginx/sites-enabled/default

3. Create a Reverse Proxy configuration file

Then, we will create a reverse proxy configuration file.

To do that, go to the sites-available directory following the path in the command below:

$ cd /etc/nginx/sites-available

Now, create a reverse proxy configuration file and open it with nano editor like this:

$ sudo nano example.conf

Copy the following lines and paste them into the file you just created:

server {
listen 80;
server_name example.com;
location / {
proxy_pass http://10.11.120.3:80;
}
}

This configuration tells that the Nginx reverse proxy is listening on port 80 and redirecting all incoming connection requests for example.com towards port 80 of 10.11.12.3 server.

4. Activate the file by creating symlink

Here, we will save the file and activate it by creating a symlink like this:

$ sudo ln -s /etc/nginx/sites-available/example.conf /etc/nginx/sites-enabled/

5. Test Nginx configuration file

It is time to test our reverse proxy configuration file for errors. To do that, run the following command:

$ sudo nginx -t

If you get the "syntax is ok" message, it means you are good to go.

6. Restart Nginx

The final step is to restart the Nginx web server so that the new reverse proxy configuration file that we just added, gets configured with the Nginx web server. Do this by running the following command: