title: how to start rails app on nginx on port 80
body: <p>I can't start my site on port 80, but only on 3000. Nginx shows standard index page. 
  Nginx config:</p>
  
  <pre><code>http {
    passenger_root /home/my_user_name/.rvm/gems/ruby-1.9.3-p125/gems/passenger-3.0.11;
    passenger_ruby /home/my_user_name/.rvm/wrappers/ruby-1.9.3-p125/ruby;
  
    include       mime.types;
    default_type  application/octet-stream;
  
    keepalive_timeout 65;
  
    server {
      listen 80;
      server_name www.my_site_name.com
      root /home/my_user_name/my_site_name/public;   # &lt;--- be sure to point to 'public'!
      passenger_enabled on;
    }
  
  }
  </code></pre>
  
  <p>commands: </p>
  
  <pre><code>passenger start -e production  # successfully started on port 3000
  
  rvmsudo passenger start -e production -p 80 # error, see below
  </code></pre>
  
  <p>Error:</p>
  
  <pre><code>*** ERROR ***
  The address 0.0.0.0:80 is already in use by another process, perhaps another
  Phusion Passenger Standalone instance.
  
  If you want to run this Phusion Passenger Standalone instance on another port,
  use the -p option, like this:
  
    passenger start -p 81
  </code></pre>
  
  <p>Thanks for any help!</p>