About Virtual Hosts


Virtual Hosts are used to run more than one domain off of a single IP address. This is especially useful to people who need to run several sites off of one virtual private server. The sites display different information to the visitors, depending on with which the users accessed the site.There is no limit to the number of virtual hosts that can be added to a VPS.
Set Up
The steps in this tutorial require the user to have root privileges. You can see how to set that up in the here Initial Server Setup. You can implement whatever username suits you. 

Additionally, you need to have apache already installed and running on your virtual server
 
If this is not the case, you can download it with this command:
sudo apt-get install apache2


Step One— Create a New Directory


The first step in creating a virtual host is to a create a directory where we will keep the new website’s information. 

This location will be your Document Root in the Apache virtual configuration file later on. By adding a -p to the line of code, the command automatically generates all the parents for the new directory.
sudo mkdir -p /var/www/example.com/public_html

You will need to designate an actual DNS approved domain, or an IP address, to test that a virtual host is working. In this tutorial we will use example.com as a placeholder for a correct domain name.
 

However, should you want to use an unapproved domain name to test the process you will find information on how to make it work on your local computer in Step Seven.
 


Step Two—Grant Permissions


We need to grant ownership of the directory to the user, instead of just keeping it on the root system.
 sudo chown -R $USER:$USER /var/www/example.com/public_html

Additionally, it is important to make sure that everyone will be able to read our new files.
 sudo chmod -R 755 /var/www

Now you are all done with permissions.


Step Three— Create the Page


Within our configurations directory, we need to create a new file called index.html
sudo nano /var/www/example.com/public_html/index.html

We can add some text to the file so we will have something to look at when the IP redirects to the virtual host.
<html>
  <head>
    <title>www.example.com</title>
  </head>
  <body>
    <h1>Success: You Have Set Up a Virtual Host</h1>
  </body>
</html>

Save and Exit


Step Four—Create the New Virtual Host File


The next step is to set up the apache configuration. We’re going to work off a duplicate—go ahead and make a copy of the file (naming it after your domain name) in the same directory:
 sudo cp /etc/apache2/sites-available/default /etc/apache2/sites-available/example.com


Step Five—Turn on Virtual Hosts


Open up the new config file:
 sudo nano /etc/apache2/sites-available/example.com

We are going to set up a virtual host in this file.

The first step is to insert a line for the ServerName under the ServerAdmin line.
  ServerName example.com

The ServerName specifies the domain name that the virtual host uses.
 

If you want to make your site accessible from more than one name (for example, with www in the URL), you can include the alternate names in your virtual host file by adding a ServerAlias Line. The beginning of your virtual host file would then look like this:
<VirtualHost *:80>
        ServerAdmin webmaster@example.com
        ServerName example.com
        ServerAlias www.example.com
  [...]

The next step is to fill in the correct Document Root. For this section, write in the extension of the new directory created in Step One. If the document root is incorrect or absent you will not be able to set up the virtual host.

The section should look like this:
 DocumentRoot /var/www/example.com/public_html

You do not need to make any other changes to this file. Save and Exit.

The last step is to activate the host, with the built in apache shortcut:
 sudo a2ensite example.com


Step Six—Restart Apache


We’ve made a lot of the changes to the configuration, and the virtual host is set up. However none of the changes that we made will take effect until Apache is restarted. Use this command to restart apache:
 sudo service apache2 restart