Basic Load Balancer Configuration Using Nginx

Nginx load balancer is a feature in Nginx that allows you to evenly distribute web traffic among multiple backend servers or nodes, helping to improve the performance, availability, and scalability of a website or application.

Nginx load balancer acts as the incoming for user requests, and then distributes those requests to available backend servers. This can be done based on certain algorithms, such as round-robin, least connections, or weighted distribution, according to our needs.

In this configuration using the Round Robin method, here's a the topology

Requirement :
- 3 VM Ubuntu 22.04 (1 Load Balancer, 2  Webserver)
- Nginx Web Server
- Domain

1. Install Nginx on Webserver 1 dan 2

use this command to install nginx

apt install nginx
systemctl enable nginx
systemctl start nginx

Then adjust the configuration to mark-off webserver 1 and 2, this configuration is set on both server

/var/www/html/index.nginx-debian.html

Restart nginx service on both node

nginx -t
systemctl restart nginx
systemctl status nginx

2. Install Nginx on Load Balancer

Now we will install nginx on Load Balancer Node

apt install nginx
systemctl enable nginx
systemctl start nginx

create a config using nano or vi on this path

/etc/nginx/nginx.conf

Add this line to the configuration http

upstream backend {
        server <masukan ip webserver 1>;
        server <masukan ip webserver 2>;
    }

    server {
        listen      80;
        server_name lb.sandyputu.my.id;

        location / {
                proxy_redirect      off;
                proxy_set_header    X-Real-IP $remote_addr;
                proxy_set_header    X-Forwarded-For $proxy_add_x_forwarded_for;
                proxy_set_header    Host $http_host;
                proxy_pass http://backend;
        }
}

Ex:

If you are done, then restart the nginx

nginx -t
systemctl restart nginx   
systemctl status nginx

3. Accessing Website

open the browser application then access to the nginx IP or access to the domain that has been pointed to the Load Balancer IP, then try periodically to reload the web, then the traffic results will change as follows.