Yosemite upgrade guide v1.0
Apache
Apache will break as it’s upgraded from v2.2 to v2.4. It will revert the /etc/apache/httpd.conf file. In this file you need to do a few things:
Search for vhosts and uncomment the line:
Include /private/etc/apache2/extra/httpd-vhosts.conf
Also find the <Directory /> block and make sure it reads as follows:
<Directory />
AllowOverride All
Require all granted
</Directory>
Then open up /etc/apache2/extra/vhosts.conf and find any instances that begin with Allow from or Order allow,deny or Order deny,allow.
Remove them and change to:
Require all granted
After all this make sure you restart apache: sudo apachectl restart
Finally, if you still have problems, try to start Apache in debug mode and see what errors you get:
sudo /usr/sbin/httpd -k start -e Debug -E /dev/stdout
MySQL
It seems MySQL doesn’t start by default. First go to the Settings on your Mac and start the MySQL service. Check everything works. Next, follow these instructions to launch MySQL automatically.
PHPStorm
PHPStorm is not yet compatible with Yosemite as it ships a new version of Java. Unfortunately you have to downgrade for now. More info here