title: CodeIgniter white screen on local dev environment
body: <p>I'm working on local creating developer environments for a CodeIgniter application.  The production application runs on Heroku so I'm not familiar with the production server configuration.</p>
  
  <p>I'm creating the developer environments with Vagrant, Ansible, Ubuntu 14.04, Apache 2.4, and PHP 5.  The Apache2 modules I'm using are mod_proxy, mod_proxy_fcgi, php5, and rewrite.  </p>
  
  <p>I get a white screen when I load the application in the browser.  </p>
  
  <p>How can I begin to diagnose the white screen?</p>