Installing the Apache Web Server

Introduction

In this section, we focus on a fundamental component of the internet's infrastructure: the web server, or alternatively called the HTTP server.

The web server is the software that makes websites available in your browsers. The basic function is to make files on the web server accessible to others via their web browsers. At a basic level, the web is essentially a world wide file system, and the web browser retrieves and displays files from web servers, much like a file explore does for local files. At a more advanced level, HTTP can also add more complexity beyond simple file access, such as providing dynamic content, APIs, and more.

Knowing how a web server functions is crucial for anyone wanting to manage or deploy web services. There are many web servers available, but in this session, I will guide you through installing and using the Apache web server. Apache is one of the most popular web server applications. We will learn how to install it, configure it, and conduct basic checks to ensure its operation. We will end this lesson by creating your first web page on your first web server.

It's important to understand the basics of an HTTP server, and therefore I ask you to read Apache's Getting Started page before proceeding with the rest of this section. Each of the main sections on that page describe the important elements that make up and serve a website. These elements include:

  • clients, servers, and URLs
  • hostnames and DNS
  • configuration files and directives
  • web site content
  • log files and troubleshooting

Installation

Before we install Apache, we need to update our systems first. This ensures we will be downloading and installing the most recent, secure version of the package.

sudo apt update
sudo apt -y upgrade

Once the machine is updated, we can install Apache using apt. First we'll use apt search to identify the specific package name. I know that a lot of results will be returned, so I will pipe | the output from apt search command through the head command to look at the initial results:

apt search apache2 | head

The package that we're interested in happens to be named apache2 on Ubuntu. The name of this package is not a given, though. On other distributions, like Fedora, the Apache package is called httpd. This is why it's important to learn and use apt search <package_name> and apt show <package_name> commands to locate desired packages before installing.

apt show apache2

Once we've confirmed that apache2 is the package that we want, install it with the apt install <package_name> command. Press Y to agree to continue after running the command below:

sudo apt install apache2

Basic checks

Once it is installed, we need to make sure the server is up and running, configure some basic things, and create a basic web site.

To start, I use the systemctl command to acquire status info about apache2 and make sure it is enabled and running:

systemctl status apache2

The output may be overwhelming at first glance, so I advise you to read each line slowly. In particular, look for key lines that show its Active and Loaded status. For example, the output shows that apache2 is enabled, which is the default for this software. The term enabled means that the software starts automatically on reboot. The output should also state that the software is active. This means that the apache2 is running and live.

Creating a web page

Since apache2 is active, let's look at the default web page.

There are (at least) two ways we can look at the default web page. We can use a command line web browser or a graphical web browser, like Firefox, Chrome, etc.

Text Based Web Browser

We have lots of command line browsers to use. I like w3m because it defaults to Vim keybindings, but many like elinks.

To check the site with w3m, we have to install it first:

sudo apt install w3m

Or if you want to try elinks, run:

sudo apt install elinks

Once the text based browser is installed, we can visit our default site using its loopback IP address. The loopback address is named localhost and always points to the local machine. It is useful for testing services, connections, and more locally. From the command line on our server, we can run either of these two commands to view localhost:

w3m 127.0.0.1

Or:

w3m localhost

If you elected to use elinks, just replace w3m with it.

We can also acquire the system's private IP address using the ip a command. There are different address ranges for the private networks. On your home network, your private IP address for a your laptop or phone might begin with 192.168.x.x. On our virtual instances, the address will begin with the number 10 and look like 10.128.0.99. The difference deals with the size of the private networks. In any case, to use the private IP address with w3m from the virtual machine's command line, we run, assuming private IP address for my local machine is 10.128.0.99:

w3m 10.128.0.99

If apache2 installed and started correctly, you should see the following text:

Apache2 Ubuntu Default Page
It works!

To exit w3m or elinks, press q and then y to confirm exit.

Graphical Browser

To view the default web page using a regular web browser, like Firefox, Chrome, Safari, Edge, or etc., you need to get your server's public IP address. To do that, log into the Google Cloud Console click on the Compute Engine link, and then click on VM instances. You should see your External IP address in the table on that page. You can copy that external IP address or simply click on it to open it in a new browser tab. If successful, you should see the graphical version of the Apache2 Ubuntu Default Page.

Note that most browsers nowadays try to force a secure HTTPS mode. If your web page is not loading, make sure your URL is http://IP-ADDRESS and not https://IP-ADDRESS.

Please take a moment to read through the text on the default page. It provides important information about where Ubuntu stores configuration files, what those files do, and the document root, which is where website files are stored.

Create a Web Page

Let's create your first web page on your first web server. The default page described above provides the location of the document root at /var/www/html. The document root may reside at a different location on a different Linux operating system, so it's important to verify that location. Remember that the web is, at its simplest, a filesystem that has been made available to the wide world. The web server is what provides access to part of the filesystem. That point of access is called the document root.

When we navigate to the document root on the command line, we'll see that there is an index.html file located in that directory. This is the Apache2 Ubuntu Default Page that we visited above in our browsers. Most web servers look for a file specifically named index.html and serve that as the default. Let's rename that index.html file, in order to back it up, and create a new one:

cd /var/www/html/
sudo mv index.html index.html.original
sudo nano index.html

Note: we use sudo in this directory because we are working on files and directories outside our home directories. Thus, be careful here about the commands you run. Any mistake may result in deleting necessary files or directories.

If you know HTML, then feel free to write some basic HTML code to get started. Otherwise, you can re-type the content below in nano or like, and then save and exit out.

<html>
<head>
<title>My first web page using Apache</title>
</head>
<body>

<h1>Welcome</h1>

<p>Welcome to my web site.
I created this site using the Apache HTTP server.</p>

</body>
</html>

If you have your site open in your web browser, reload the page, and you should see the new text.

You can still view the original default page by specifying its name in the URL. Remember that web browsers are, at their most basic, simply file viewers. So it makes sense that you simply have to specify the name of the file you want to view. For example, if your public IP address is 55.222.55.222, then you'd specify it like so:

http://55.222.55.222/index.html.original

Conclusion

In this section, we learned about the Apache HTTP server. We learned how to install it on Ubuntu, how to use a systemctl command to check its status, how to create a basic web page in /var/www/html, how to view that web page using the w3m command line browser and in our graphical browser,

In the next section, we will install PHP, which will provide the language needed to connect to the relational database MySQL. This will enable more data driven web sites and begin to transform out sites from basic file viewers to full fledged applications.