Solution to: Admin interface quite empty, shows only text


Expected Behaviour:

accessing http://pi.hole/admin/ shows admin interface

Actual Behaviour:

Site loads correctly (HTML and JavaScript), but admin interface looks like this:

Looking at the source code of the page it starts with

<?php /*
*    Pi-hole: A black hole for Internet advertisements


During installation of Pi-hole you decided to not install lighttpd, because you already have a webserver like Apache2 running - but you are missing PHP, so install that:

$ sudo apt-get install php