The scope of this article is to discuss the possible configurations with Apache httpd 2.2 and php. Using mod_php in most cases is not a viable solution, since it introduces scalability issues with the added RAM requirement for each httpd process. Additionally, it precludes the use of threaded MPMs since php extensions are not thread-safe in many cases.
The ideal configuration is a light threaded httpd process that communicates with an external fastcgi server, such as PHP-FPM.
The first recipe uses mod_fastcgi:
Alias /php5.fcgi /var/www/fcgi/php5.fcgi
FastCGIExternalServer /var/www/fcgi/php5.fcgi -flush -host 127.0.0.1:9000
# Invent a new handler name and use it for PHP files
AddHandler my-fastcgi .php
# Requests for *.php are actually fed to php-fastcgi as an argument
Action my-fastcgi /php5.fcgi
Deny from all
Allow from all
Thanks to Guillaume Seigneuret for the kickstart on that recipe!