Mac OS X vhosts not working after yoemite / el capitan upgrade

This is because you forgot to back up your httpd.conf… – easily fixed:

First, back up the current httpd.conf:

(you’ll need to be root, so either su or run the following commands with sudo)

cd /etc/apache2

mv httpd.conf httpd.conf.preUpgrade

mv httpd.conf~previous httpd.conf

and then restart apache:

apachectl restart

now your local vhosts will work again.