Apache is a modularized web server that can be extended by dynamically loading extra modules as and when required. This provides the flexibility to run a bare minimum web server or a fully featured box with modules to support compression, SSL, redirects, language modules, and more. Apache provides multiple connection processing algorithms called multi-processing modules (MPM). It provides an option to create a separate single threaded process for each new request (mpm_prefork), a multi-threaded process that can handle multiple concurrent requests (mpm_worker), or the latest development of mpm_event, which separates the active and idle connections.
Installing the Apache web server
Follow these steps to install and configure the Apache web server:
Step 1 : Install Apache2 from the Ubuntu package repository:
sudo apt-get update
sudo apt-get install apache2
Step 2 : Check if Apache2 has installed successfully. The command wget should download the index.html file:
wget 127.0.0.1
Step 3 : You can also open a browser on a local machine and point it to the server IP address. You should see a default It works! page customized for Ubuntu:
Creating the first virtual host
Step 1 : Now, let’s proceed with creating our first virtual host. First create a directory structure. Change the directory to /var/www/ and create a new directory for the contents of our site:
cd /var/www
sudo mkdir example.com
Step 2 : Change the ownership and group of the directory example.com:
sudo chown $USER:www-data example.com
Step 3 : Set the file permissions to secure web contents:
sudo chmod 750 example.com
Step 4 : Create the required directories under the example.com directory:
cd example.com
mkdir public_html
Step 5: Create a index.html file under the public_html directory:
echo '<b>Hello World ...</b>' > public_html/index.html
Step 6 : Next, we need to set up a new virtual host under the Apache configuration.
Step 7 : Copy the default Virtual Host file under /etc/apache2/sites-available and use it as a starting point for our configuration:
cd /etc/apache2/sites-available
sudo cp 000-default.conf example.com.conf
Step 8 : Edit example.com.conf to match it with the following example. Change the parameters as per your requirements:
<VirtualHost *:80>
ServerName example.com
ServerAlias www.example.com
ServerAdmin webmaster@example.com
DocumentRoot /var/www/example.com/public_html
ErrorLog ${APACHE_LOG_DIR}/error.log
CustomLog ${APACHE_LOG_DIR}/access.log combined
</VirtualHost>
Step 9 : Save the changes and exit example.com.conf.
Step 10 : If you are using the same port as the default VirtualHost, do not forget to disable the default one:
sudo a2dissite 000-default.conf
Step 11 : Finally, enable our new VirtualHost with a2ensite and reload Apache
sudo a2ensite example.com.conf
sudo service apache2 reload
Step 12: Start your browser and point it to the domain or IP address of your server:
Enabling HTTP/2 in Apache
If you are looking for HTTP2 support, Apache does provide a separate module for that. Apache version 2.4.17 ships with a module, mod_http2, that implements the latest HTTP version, HTTP2.
Step 1 : you can enable mod_http2 as follows:
sudo a2enmod http2
Step 2 : Next, edit the specific virtual host file to enable the HTTP2 protocol for a specific site. Note that you need to configure your site to use an SSL/TLS connection:
<VirtualHost *:443>
Protocols h2 http/1.1
...
</VirtualHost>Step 3 : Finally, restart your Apache server:
sudo service apache2 restart