AresCentral and the forums here had a brief downtime this morning after I restarted the server for routine operating system updates. Somehow Apache (which I never even knew was installed) got activated and it was conflicting with nginx.
I mention it just in case anybody else has a weird problem with the website not restarting after rebooting the server for an OS update. sudo service nginx restart was returning an error about port 80 already being in use.