Hello https://www.howtoforge.com/tutorial/install-php-7-on-debian-8-jessie/ Is this guide valid for Debian 7.8? are the same steps for a production server with ISPConfig Version: 3.1.11? Regards
No, it is for Debian version 8. Debian version 7 is Wheezy, version 8 is Jessie. Maybe you should upgrade to a newer Debian? Wheezy long term support ends in May 2018. On the other hand, I believe it does work for ISPConfig 3.1.11.