A passenger apache directive, used on my development PC so that I can mimic the production environment and debug errors caused by the app being hosed in a sub-uri. For example, issues with redirects going to http root rather than app root.

self_assessment.conf

   <VirtualHost *:80>

      ServerName localhost
      DocumentRoot /home/rob/public_html
      <Directory /home/rob/public_html>
          Allow from all
      </Directory>

      RackBaseURI /self_assessment                
      <Directory /home/rob/web/select_assessment>   
        Options -MultiViews              
      </Directory>

      <Location /self_assessment>
        PassengerRuby /home/rob/.rvm/wrappers/ruby-1.9.3-p286@self_assessment/ruby
        RailsEnv development
      </Location>
 
   </VirtualHost>