Introduction

Nginx is one of the most popular web servers in the world and is responsible for hosting some of the largest and highest-traffic sites on the internet. It is more resource-friendly than Apache in most cases and can be used as a web server or reverse proxy.
In this guide, we’ll explain how to install Nginx on your Ubuntu 18.04 server. For a more detailed version of this tutorial, please refer to How To Install Nginx on Ubuntu 18.04.

Prerequisites

Before you begin this guide, you should have the following:

An Ubuntu 18.04 server and a regular, non-root user with sudo privileges. Additionally, you will need to enable a basic firewall to block non-essential ports. You can learn how to configure a regular user account and set up a firewall by following our initial server setup guide for Ubuntu 18.04.

When you have an account available, log in as your non-root user to begin.

Step 1 – Installing Nginx

Because Nginx is available in Ubuntu’s default repositories, you can install it using the apt packaging system.
Update your local package index:

sudo apt update

Install Nginx:

sudo apt install nginx

Step 2 – Adjusting the Firewall

If you followed the prerequisite server setup tutorial, then you have the UFW firewall enabled. Check the available ufw application profiles with the following command:

sudo ufw app list


Available applications:
  Nginx Full
  Nginx HTTP
  Nginx HTTPS
  OpenSSH

Let’s enable the most restrictive profile that will still allow the traffic you’ve configured, permitting traffic on port 80:

sudo ufw allow 'Nginx HTTP'

Verify the change:

sudo ufw status


Status: active

To                         Action      From
--                         ------      ----
OpenSSH                    ALLOW       Anywhere                  
Nginx HTTP                 ALLOW       Anywhere                  
OpenSSH (v6)               ALLOW       Anywhere (v6)             
Nginx HTTP (v6)            ALLOW       Anywhere (v6)

Step 3 – Checking your Web Server

Check with the systemd init system to make sure the service is running by typing:

systemctl status nginx


● nginx.service - A high performance web server and a reverse proxy server
   Loaded: loaded (/lib/systemd/system/nginx.service; enabled; vendor preset: enabled)
   Active: active (running) since Fri 2018-04-20 16:08:19 UTC; 3 days ago
     Docs: man:nginx(8)
 Main PID: 2369 (nginx)
    Tasks: 2 (limit: 1153)
   CGroup: /system.slice/nginx.service
           ├─2369 nginx: master process /usr/sbin/nginx -g daemon on; master_process on;
           └─2380 nginx: worker process

Access the default Nginx landing page to confirm that the software is running properly through your IP address:

http://your_server_ip

You should see the default Nginx landing page:

When using the Nginx web server, you can use server blocks (similar to virtual hosts in Apache) to encapsulate configuration details and host more than one domain from a single server. We will set up a domain called example.com, but you should replace this with your own domain name. To learn more about setting up a domain name with DigitalOcean, see our introduction to DigitalOcean DNS.
Create the directory for example.com, using the -p flag to create any necessary parent directories:

sudo mkdir -p /var/www/example.com/html

Assign ownership of the directory:

sudo chown -R $USER:$USER /var/www/example.com/html

The permissions of your web roots should be correct if you haven’t modified your umask value, but you can make sure by typing:

sudo chmod -R 755 /var/www/example.com

Create a sample index.html page using nano or your favorite editor:

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

Inside, add the following sample HTML:
/var/www/example.com/html/index.html

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

Save and close the file when you are finished.
Make a new server block at /etc/nginx/sites-available/example.com:

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

Paste in the following configuration block, updated for our new directory and domain name:
/etc/nginx/sites-available/example.com

server {
        listen 80;
        listen [::]:80;

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

        server_name example.com www.example.com;

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

Save and close the file when you are finished.
Enable the file by creating a link from it to the sites-enabled directory:

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

Two server blocks are now enabled and configured to respond to requests based on their listen and server_name directives:

example.com: Will respond to requests for example.com and www.example.com.
default: Will respond to any requests on port 80 that do not match the other two blocks.

To avoid a possible hash bucket memory problem that can arise from adding additional server names, it is necessary to adjust a single value in the /etc/nginx/nginx.conf file. Open the file:

sudo nano /etc/nginx/nginx.conf

Find the server_names_hash_bucket_size directive and remove the # symbol to uncomment the line:
/etc/nginx/nginx.conf

...
http {
    ...
    server_names_hash_bucket_size 64;
    ...
}
...

Test for syntax errors:

sudo nginx -t

Restart Nginx to enable your changes:

sudo systemctl restart nginx

Nginx should now be serving your domain name. You can test this by navigating to http://example.com, where you should see something like this:

Conclusion

Now that you have your web server installed, you have many options for the type of content to serve and the technologies you want to use to create a richer experience.
If you’d like to build out a more complete application stack, check out this article on how to configure a LEMP stack on Ubuntu 18.04.