I have no idea how, but somehow (in the past few minutes) that URI works for me too (whether with a browser or
curl). Now I can log in!
I turned on debug and forensic logging in Apache, which might have some insights. Still can’t get
php7.0-fpm to log anything, which I suspect is where things are going wrong.
But, as soon as I do and I request anything (e.g.,
https://cloud.koehn.com/index.php/apps/files/), I get back a 302 (redirect) to
https://cloud.koehn.com/index.php/apps/files/), no matter what URI was requested in the first place.
And a request for
https://cloud.koehn.com/index.php/core/js/oc.js still results in the index page being returned.