After doing a release upgrade
do-release-upgrade
from Ubuntu 12.04 to 14.04 my websites were going to the default vhost for apache. After looking at /etc/apache2/apache2.conf it had changed from looking for .cfg to .conf for the vhosts files. I just added the .cfg in addition to the .conf so both files would work at around line 218 in apache2.conf to include the virtual host configuration.
IncludeOptional sites-enabled/*.cfg