The Apache web server is among the many packages that make up the Ubuntu operating system. The scalability and resilience of Ubuntu make it an ideal platform for hosting even the most heavily trafficked websites.

This chapter will explain how to configure an Ubuntu system using Apache to act as a web server, including secure (HTTPS) and insecure (HTTP) configurations.

Requirements for Configuring an Ubuntu Web Server

To set up your own website, you need a computer (or cloud server instance), an operating system, a web server, a domain name, a name server, and an IP address.

As previously mentioned, Ubuntu supports the Apache web server, which can easily be installed once the operating system is up and running. In addition, a domain name can be registered with any domain name registration service.

If you are running Ubuntu on a cloud instance, the IP address assigned by the provider will be listed in the server overview information. However, if you are hosting your own server and your internet service provider (ISP) has assigned a static IP address, you must associate your domain with that address. This is achieved using a name server, and all domain registration services will provide this service.

If you do not have a static IP address (i.e., your ISP provides you with a dynamic address that changes frequently), you can use one of several free Dynamic DNS (DDNS or DynDNS for short) services to map your dynamic IP address to your domain name.

Once you have configured your domain name and your name server, the next step is to install and configure your web server.

Installing the Apache Web Server Packages

The current release of Ubuntu typically does not install the Apache web server by default. To check whether the server is already installed, run the following command:

# apt -qq list apache2Code language: plaintext (plaintext)

If apt generates output similar to the following, the apache server is already installed:

apache2/jammy-updates,now 2.4.52-1ubuntu4.5 amd64 [installed]Code language: plaintext (plaintext)

If the apt output does not list the package or include the [installed] status, run the following command at the command prompt to perform the Apache installation:

# apt install apache2Code language: plaintext (plaintext)

Configuring the Firewall

Before starting and testing the Apache web server, the firewall will need to be modified to allow the webserver to communicate with the outside world. By default, the HTTP and HTTPS protocols use ports 80 and 443 respectively so, depending on which protocols are being used, either one or both of these ports will need to be opened. If your Ubuntu system is being protected by the Uncomplicated Firewall, the following command can be used to enable only insecure web traffic (HTTP):

# ufw allow ApacheCode language: plaintext (plaintext)

To enable only secure (HTTPS) traffic:

# ufw allow 'Apache Secure'Code language: plaintext (plaintext)

Alternatively, enable both secure and insecure web traffic as follows:

# ufw allow 'Apache Full'Code language: plaintext (plaintext)

If you are using firewalld, the following commands can be used to open the HTTP and HTTPS ports. When opening the ports, be sure to specify the firewall zone that applies to the internet-facing network connection:

# firewall-cmd --permanent --zone=<zone> --add-port=80/tcp
# firewall-cmd --permanent --zone=<zone> --add-port=443/tcCode language: plaintext (plaintext)

After opening the necessary ports, be sure to reload the firewall settings:

# firewall-cmd --reloadCode language: plaintext (plaintext)

On cloud-hosted servers, enabling the appropriate port for the server instance within the cloud console may also be necessary. Check the documentation for the cloud provider for steps to do this.

Port Forwarding

Suppose the Ubuntu system hosting the web server sits on a network protected by a firewall (another computer running a firewall, router, or wireless base station containing built-in firewall protection). In that case, you must configure the firewall to forward ports 80 and 443 to your web server system. The mechanism for performing this differs between firewalls and devices, so check your documentation to find out how to configure port forwarding.

Starting the Apache Web Server

Once the Apache server is installed and the firewall configured, the next step is to verify that the server is running and start it if necessary.

To check the status of the Apache service from the command line, enter the following at the command prompt:

# systemctl status apache2Code language: plaintext (plaintext)

If the above command indicates that the apache2 service is not running, it can be launched from the command line as follows:

# systemctl start apache2Code language: plaintext (plaintext)

If you would like the Apache httpd service to start automatically when the system boots, run the following command:

# systemctl enable apache2Code language: plaintext (plaintext)

Testing the Web Server

Once the installation is complete, the next step is verifying the web server is running.

If you have access (either locally or remotely) to the desktop environment of the server, start up a web browser and enter http://127.0.0.1 in the address bar (127.0.0.1 is the loop-back network address that tells the system to connect to the local machine). If everything is set up correctly, the browser should load the test page shown in Figure 31-1:

If the desktop environment is unavailable, connect either from another system on the same local network as the server, or use the external IP address assigned to the system if it is hosted remotely.

Configuring the Apache Web Server for Your Domain

The next step in setting up your web server is configuring it for your domain name. To configure the web server, begin by changing directory to /etc/apache2, which, in turn, contains several files and sub-directories. The main configuration file is named apache2.conf and serves as the central point for organizing the modular configuration files located in the sub-directories. For example, the apache2.conf file includes a line to import the configuration settings declared in the files located in the sites-enabled folder:

# Include the virtual host configurations:
IncludeOptional sites-enabled/*.confCode language: plaintext (plaintext)

Similarly, the apache2.conf file imports the ports.conf file, which defines the ports on which the Apache server listens for network traffic.

To configure a website domain on Ubuntu, begin by changing directory to /etc/apache2. In this directory, you will find two sub-directories, sites-available and sites-enabled. Change directory into sites-available. In this directory you will find a default file which may be used as a template for your own site.

Copy the default file to a new file with a name that matches your domain name. For example:

# cp 000-default.conf myexample.confCode language: plaintext (plaintext)

Edit your myexample.com file using your favorite editor where it will appear as follows:

<VirtualHost *:80>
        # The ServerName directive sets the request scheme, hostname and port that
        # the server uses to identify itself. This is used when creating
        # redirection URLs. In the context of virtual hosts, the ServerName
        # specifies what hostname must appear in the request’s Host: header to
        # match this virtual host. For the default virtual host (this file) this
        # value is not decisive as it is used as a last resort host regardless.
        # However, you must set it for any further virtual host explicitly.
        #ServerName www.example.com

        ServerAdmin webmaster@localhost
        DocumentRoot /var/www/html

        # Available loglevels: trace8, ..., trace1, debug, info, notice, warn,
        # error, crit, alert, emerg.
        # It is also possible to configure the loglevel for particular
        # modules, e.g.
        #LogLevel info ssl:warn

        ErrorLog ${APACHE_LOG_DIR}/error.log
        CustomLog ${APACHE_LOG_DIR}/access.log combined

        # For most configuration files from conf-available/, which are
        # enabled or disabled at a global level, it is possible to
        # include a line for only one particular virtual host. For example the
        # following line enables the CGI configuration for this host only
        # after it has been globally disabled with “a2disconf”.
        #Include conf-available/serve-cgi-bin.conf
</VirtualHost>Code language: HTML, XML (xml)

The ServerAdmin directive defines an administrative email address for people wishing to contact the webmaster for your site. Change this to an appropriate email address where you can be contacted:

ServerAdmin [email protected]Code language: plaintext (plaintext)

Next, the ServerName directive needs to be uncommented (in other words, remove the ‘#’ character prefix) and defined so that the web server knows which virtual host this configuration file refers to:

ServerName myexample.comCode language: plaintext (plaintext)

In the next stage, we need to define where the website files are going to be located using the DocumentRoot directive. The tradition is to use /var/www/domain-name:

DocumentRoot /var/www/myexample.comCode language: plaintext (plaintext)

Having completed the changes, we now need to enable the site as follows:

# a2ensite myexample.confCode language: plaintext (plaintext)

This command creates a symbolic link from the myexample.conf file in the sites-available directory to the sites-enabled folder.

With the site enabled, run the following command to disable the default test site:

# a2dissite 000-default.confCode language: plaintext (plaintext)

Next, create the /var/www/myexample.com directory and place an index.html file in it. For example:

<html>
<title>Sample Web Page</title>
<body>
Welcome to MyExample.com
</body>
</html>Code language: HTML, XML (xml)

With these changes made, run the apache2ctl command to check the configuration files for errors:

# apache2ctl configtest
Syntax OKCode language: plaintext (plaintext)

If no errors are reported, reload the Apache web server to make sure it picks up our new settings:

# systemctl reload apache2Code language: plaintext (plaintext)

Finally, check that the server configuration works by opening a browser window and navigating to the site using the domain name instead of the IP address. The web page that loads should be the one defined in the index.html file created above.

The Basics of a Secure Website

The web server and website created in this chapter use the HTTP protocol on port 80 and, as such, are considered to be insecure. The problem is that the traffic between the web server and the client (typically a user’s web browser) is transmitted in clear text. In other words, the data is unencrypted and susceptible to interception. While not a problem for general web browsing, this is a severe weakness when performing tasks such as logging into websites or transferring sensitive information such as identity or credit card details.

These days, websites are expected to use HTTPS, which uses either Secure Socket Layer (SSL) or Transport Layer Security (TLS) to establish secure, encrypted communication between a web server and a client. This security is established through the use of public, private, and session encryption together with certificates.

To support HTTPS, a website must have a certificate issued by a trusted authority known as a Certificate Authority (CA). When a browser connects to a secure website, the web server sends back a copy of the website’s SSL certificate, which also contains a copy of the site’s public key. The browser then validates the authenticity of the certificate with trusted certificate authorities.

If the certificate is valid, the browser uses the public key sent by the server to encrypt a session key and pass it to the server. The server decrypts the session key using the private key to send an encrypted acknowledgment to the browser. Once this process is complete, the browser and server use the session key to encrypt all subsequent data transmissions until the session ends.

Configuring Apache for HTTPS

By default, the Apache server does not include the necessary module to implement a secure HTTPS website. The first step, therefore, is to enable the Apache mod_ssl module on the server system as follows:

# a2enmod sslCode language: plaintext (plaintext)

Restart apache2 after the installation completes to load the new module into the Apache server:

# systemctl restart apache2Code language: plaintext (plaintext)

Check that the module has loaded into the server using the following command:

# apache2ctl -M | grep ssl_module
 ssl_module (shared)Code language: plaintext (plaintext)

Once the ssl module is installed, repeat the steps from the previous section of this chapter to create a configuration file for the website, this time using the sites-available/default-ssl.conf file as the template for the site configuration file. Assuming the module is installed, the next step is to generate an SSL certificate for the website.

Obtaining an SSL Certificate

The certificate for a website must be obtained from a Certificate Authority. Several options are available at a range of prices. By far the best option, however, is to obtain a free certificate from Let’s Encrypt at the following URL: https://letsencrypt.org/

Obtaining a certificate from Let’s Encrypt involves installing and running the Certbot tool. This tool will scan the Apache configuration files on the server and provides the option to generate certificates for any virtual hosts configured on the system. It will then generate the certificate and add virtual host entries to the Apache configuration for the corresponding websites.

Follow the steps on the Let’s Encrypt website to download and install Certbot on your Ubuntu system, then run the certbot tool as follows to generate and install the certificate:

# certbot --apacheCode language: plaintext (plaintext)

After requesting an email address and seeking terms of service acceptance, Certbot will list the domains found in the httpd.conf file and allow the selection of one or more sites for which a certificate will be installed. Certbot will then perform some checks before obtaining and installing the certificate on the system:

Which names would you like to activate HTTPS for?
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
1: www.myexample.com
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Select the appropriate numbers separated by commas and/or spaces, or leave input
blank to select all options shown (Enter ‘c’ to cancel): 1
Obtaining a new certificate
Performing the following challenges:
http-01 challenge for www.myexample.com
Waiting for verification...
Cleaning up challenges
Created an SSL vhost at /etc/httpd/conf/httpd-le-ssl.conf
Deploying Certificate to VirtualHost /etc/httpd/conf/httpd-le-ssl.conf
Enabling site /etc/httpd/conf/httpd-le-ssl.conf by adding Include to root configurationCode language: plaintext (plaintext)

Certbot will also create a new file named myexample-le-ssl.conf in the /etc/apache2/sites-available directory containing a secure virtual host entry for each domain name for which a certificate has been generated and enabled the site so that a link to the file is made in the /etc/apache2/sitesenabled directory. These entries will be similar to the following:

<IfModule mod_ssl.c>
<VirtualHost *:443>
    ServerAdmin [email protected]
    ServerName www.myexample.com
    DocumentRoot /var/www/myexample
    ErrorLog logs/myexample_error_log
    CustomLog logs/myexample_access_log combined
 
SSLCertificateFile /etc/letsencrypt/live/www.myexample.com/fullchain.pem
SSLCertificateKeyFile /etc/letsencrypt/live/www.myexample.com/privkey.pem
Include /etc/letsencrypt/options-ssl-apache.conf
</VirtualHost>
</IfModule>Code language: HTML, XML (xml)

Finally, Certbot will ask whether the server should redirect future HTTP web requests to HTTPS. In other words, if a user attempts to access http://www.myexample.com, the web server will redirect the user to https://www.myexample.com:

Please choose whether or not to redirect HTTP traffic to HTTPS, removing HTTP access.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
1: No redirect - Make no further changes to the webserver configuration.
2: Redirect - Make all requests redirect to secure HTTPS access. Choose this for
new sites, or if you’re confident your site works on HTTPS. You can undo this
change by editing your web server’s configuration.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Select the appropriate number [1-2] then [enter] (press ‘c’ to cancel): 2Code language: plaintext (plaintext)

If you are currently testing the HTTPS configuration and would like to keep the HTTP version live until later, select the No redirect option. Otherwise, redirecting to HTTPS is generally recommended.

Once the certificate has been installed, test it in a browser at the following URL (replacing myexample.com with your own domain name):

https://www.ssllabs.com/ssltest/analyze.html?d=www.myexample.com

If the certificate configuration is successful, the SSL Labs report will provide a high rating, as shown in Figure 31-2:

As a final test, open a browser window and navigate to your domain using the https:// prefix. The page should load as before, and the browser should indicate that the connection between the browser and server is secure (usually indicated by a padlock icon in the address bar, which can be clicked for additional information):

Summary

An Ubuntu system can host websites by installing the Apache web server. Insecure (HTTP) and secure (HTTPS) websites can be deployed on Ubuntu. Secure websites use either Secure Socket Layer (SSL) or Transport Layer Security (TLS) to establish encrypted communication between the web server and client through public, private, and session encryption, together with a certificate issued by a trusted Certificate Authority.