sudo service a2ensite gdf code example
Example: a2ensite example.
a2ensite /etc/apache2/sites-available/new-domain.conf
//-----------------
a2dissite /etc/apache2/sites-available/new-domain.conf
a2ensite /etc/apache2/sites-available/new-domain.conf
//-----------------
a2dissite /etc/apache2/sites-available/new-domain.conf