Hi, If follow "The Perfect Server - Debian 9 (Stretch) with Apache, BIND, Dovecot, PureFTPD and ISPConfig 3.1" in a fresh new installaton, my question is, if I can use "How to install PHP 7.x as PHP-FPM & FastCGI for ISPConfig 3.1 with apt on Debian 8 and 9" after installation or there's a especial consideration. Please help me with this. Regards,