ubuntu - Only one Apache virtualhost configuration comes into effect

I'm using Apache 2.4 on an installation of Ubuntu 14.04, and I'm in the process of configuring Apache "virtualhosts" in order to be able to serve different content for different hostnames.

I'm trying to configure Apache such that when one tries to access the server with the hostname (www.)example1.com, content from /var/www/example1 is served; however, if one tries to access the server with it's IP address, or any other hostname except for (www.)example1.com (for example, via directly accessing it through the IP, or through any other hostname pointing at this IP) content from /var/www/html is served instead.

I have the following configuration files under /etc/apache2/sites-available:

/etc/apache2/sites-available/example1.conf:

    DocumentRoot /var/www/example1
    ServerAlias www.example1.com
    ErrorLog ${APACHE_LOG_DIR}/ex1_error.log
    CustomLog ${APACHE_LOG_DIR}/ex1_access.log combined

/etc/apache2/sites-available/000-default.conf:

    DocumentRoot /var/www/html
    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined

However, when I try to access the website by direct access or through the other hostnames pointing at this IP, I get the content served from /var/www/example1 and not from /var/www/html.

What could be the issue here, and how can I fix it?

Answer

On 2.4 use _default_:

     DocumentRoot /var/www/html
     ErrorLog ${APACHE_LOG_DIR}/error.log
     CustomLog ${APACHE_LOG_DIR}/access.log combined