How to Setup Load Balancing with Nginx in Linux

Prerequisites

You must have root access or sudo access to your server. Connect your server console with privileged access. Configure your site on backend servers.

Step 1 – Install Nginx Server

First of all, Login to your server with SSH access. Windows users can use PuTTY or alternatives to SSH into the server. Now install Nginx using Linux package manager. Nginx package is available under default yum and apt repositories.

Using Apt-get:

$ sudo apt-get install nginx

Using Yum:

$ sudo yum install nginx

Using DNF:

$ sudo dnf install nginx

Step 2 – Setup VirtualHost with Upstream

Let’s create a Nginx virtual host configuration file for your domain. Below is my minimal settings configuration file.

/etc/nginx/conf.d/www.example.com.conf

upstream remote_servers  {
   server remote1.example.com;
   server remote2.example.com;
   server remote3.example.com;
}

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

Step 3 – Other Useful Directives

You may also use some more useful settings to more customize and optimize your load balancer with Nginx. For example set, the weight and IP hash like below with configuration.

Weight

upstream remote_servers  {
   server remote1.example.com weight=1;
   server remote2.example.com weight=2;
   server remote3.example.com weight=4;
}

IP Hash

upstream remote_servers {
   ip_hash;
   server   remote1.example.com;
   server   remote2.example.com;
   server   remote3.example.com  down;
 }

Step 4 – Restart Nginx Service

After making all the changes, restart Nginx service with the following command.

$ sudo systemctl restart nginx.service