I've had Phusion Passenger working for a few of my sites for months. Then, today, it stopped working for a single site. I hadn't changed anything (I hadn't even SSH'ed into the server for a week), and everything is set up the way it should for it to work. Plus, it's working fine for other sites! I'm about to pull my hair out trying to find out what's wrong, so I was hoping y'all could help.

Passenger is not working on kerricklong.com -- I only get the "It works!" Apache default page. If I look at the headers, it's not even serving the X-Powered-By: Phusion Passenger (mod_rails/mod_rack) header that I get on my other (currently working) Passenger-powered sites on the same server running Ubuntu Server 10.04.

The following is in my /etc/apache2/sites-available/kerricklong.com file, but it's identical (with names and paths changed) to the configuration file for the site that is working.

<VirtualHost *:80>
  ServerAdmin [email protected]
  ServerName kerricklong.com
  ServerAlias *.kerricklong.com
  DocumentRoot /redacted/path/to/kerricklong.com/public
  ErrorLog /redacted/path/to/kerricklong.com/logs/error.log
  <Directory /redacted/path/to/kerricklong.com/public>
    Allow from all
    Options -MultiViews
    Include /etc/apache2/h5bp.conf
  </Directory>
  php_flag engine off
</VirtualHost>

I've got the necessary tmp/, logs/, and public/ directories, along with config.ru.

I've also run sudo a2dissite then sudo a2ensite, sudo service apache2 restart, and reboot the server to try to fix it. What gives?