Using Multiple PHP Versions (PHP-FPM & FastCGI) With ISPConfig 3 (CentOS 6.3)

Since ISPConfig 3.0.5, it is possible to use multiple PHP versions on one server and select the optimal PHP version for a website. This feature works with PHP-FPM (starting with PHP 5.3) and FastCGI (all PHP 5.x versions). This tutorial shows how to build PHP 5.3 and PHP 5.4 as a PHP-FPM and a FastCGI version on a CentOS 6.3 server. These PHP versions can be used together with the default PHP (installed through yum) in ISPConfig.

http://www.howtoforge.com/how-to-use-multiple-php-versions-php-fpm-and-fastcgi-with-ispconfig-3-centos-6.3

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