CA stopped giving me a login screen
This installation has been going strong for a few years and all I've ever done is maintain the server and update the SSL Cert each year. However recently something broke because now I don't get a login screen anymore. I'm at a loss to find what the cause of the issue is. Usually when I test it I go to localhost/index.php/system/Auth/DoLogin and I get a collective access login screen. That's no longer working. It's just a blank screen. no error.
"apache2ctl configtest" gives me "Syntax OK"
"systemctl status apache2 | grep -i active" gives me "Active: active (running)..." etc and the time it's been running since I last rebooted or restarted apache
This is all on an old ubuntu 16.04 server that I maintain for the girl scouts. I would appreciate any tips or ideas on what to do. I am REALLY unfamiliar with anything in CA, like even the install directory. And I'm at the limits on my linux knowledge.
What I can do is prove that apache is working and get a collective access installer page to show up by going to localhost/install/
Screenshot attached. I'm guessing that's the version installed.