Apache2 enable / disable sites & modules

Enable site (virtual host)

sudo a2ensite [filename.conf]

Disable site

sudo a2dissite [filename.conf]

Enable an apache2 module

sudo a2enmod [module_name]

Disable an apache2 module

sudo a2dismod [module_name]

Force reload the server

sudo /etc/init.d/apache2 force-reload

OR

sudo service apache2 reload