Creating virtual hosts (server blocks) in Nginx

Comprehensive Guide to Creating Virtual Hosts (Server Blocks) in Nginx for Web Developers

Whether you're a seasoned system administrator, a web developer, or just dipping your toes into the ocean of server management, understanding how to set up virtual hosts (also known as server blocks) in Nginx can greatly enhance your ability to host multiple websites on a single server. This guide aims to provide an in-depth look at creating and managing virtual hosts in Nginx, tailored specifically for Linux environments.

What is Nginx?

Nginx (pronounced “Engine-X”) is a high-performance HTTP and reverse proxy server, a mail proxy server, and a generic TCP/UDP proxy server, known for its high performance, stability, rich feature set, simple configuration, and low resource consumption.

What are Virtual Hosts?

Virtual hosts or server blocks in Nginx allow you to run more than one website on a single machine. With virtual hosts, you can specify server settings for each site individually, which can be extremely useful for a host managing multiple domains, or even for developers who want to test their applications on their local machines before taking them live.

Prerequisites

Before you start setting up virtual hosts, you’ll need the following:

A running Linux server (Ubuntu, CentOS, etc.)
Nginx installed on your server (most Linux distributions have Nginx in their package repositories)
Root or sudo privileges
Domain names pointed at your server (DNS settings configured to point to your server’s IP)

Step 1: Install Nginx

If Nginx is not installed on your server, you can install it using your package manager. For Ubuntu and Debian systems, use:

sudo apt update
sudo apt install nginx

For CentOS, RHEL, and Fedora (using dnf):

sudo dnf install nginx
sudo systemctl start nginx
sudo systemctl enable nginx

For openSUSE (using zypper):

sudo zypper install nginx
sudo systemctl start nginx
sudo systemctl enable nginx

Once installed, you can verify that Nginx is running by accessing your server’s IP address in a web browser. You should see a default Nginx landing page.

Step 2: Create Directory Structure

For each virtual host, you should have a separate directory that contains the website’s files. A common structure looks something like this:

sudo mkdir -p /var/www/example.com/html
sudo chmod -R 755 /var/www

Replace example.com with your domain name.

Step 3: Create Index Page

Create a sample index.html file in the directory you just created to test the virtual host:

sudo nano /var/www/example.com/html/index.html

Enter the following HTML code or something similar:

<html>
    <head>
        <title>Welcome to Example.com!</title>
    </head>
    <body>
        <h1>Success! The Example.com server block is working!</h1>
    </body>
</html>

Step 4: Configure Nginx Server Block

Next, you need to configure the virtual host (server block). Start by copying the default server block as a template:

sudo cp /etc/nginx/sites-available/default /etc/nginx/sites-available/example.com

Edit the new configuration file:

sudo nano /etc/nginx/sites-available/example.com

Adjust the file to match the following configuration, replacing example.com with your domain name:

server {
    listen 80;
    server_name example.com www.example.com;

    root /var/www/example.com/html;
    index index.html index.htm index.nginx-debian.html;

    location / {
        try_files $uri $uri/ =404;
    }
}

Step 5: Enable the Server Block

To enable the new server block, create a symlink in the sites-enabled directory:

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

Step 6: Test Configuration

Before reloading Nginx, it’s important to test the configuration for syntax errors:

sudo nginx -t

If everything is OK, proceed to reload Nginx to apply the changes:

sudo systemctl reload nginx

Step 7: Final Testing

Now navigate to http://example.com in your browser. You should see the welcome message you created earlier, indicating that your Nginx server block is configured and working correctly.

Conclusion

Setting up Nginx with multiple server blocks (virtual hosts) enables you to host multiple websites efficiently and securely on a single server. With the basic configuration complete, you can extend each server block's configurations to include SSL/TLS encryption, caching strategies, and more, depending on your specific requirements. Now that you understand the fundamentals, you’re well on your way to becoming proficient in managing web applications with Nginx. Happy hosting!