title: How to run Rails on port 80 on AWS?
body: <p>I'm trying to reboot Rails application on AWS Amazon Linux.
  I rebooted the instance by AWS console, but I can't access to the service through port 80.</p>
  
  <p>The conditions are:</p>
  
  <ol>
  <li><p>Application was working fine before reboot.</p></li>
  <li><p>Application works on port 3000.</p></li>
  <li><p>Application can run on port 80 (like rails s -d -b 0.0.0.0 -p 80).</p></li>
  <li><p>Security group of AWS says it's open 80 for HTTP on inbound.</p></li>
  </ol>
  
  <p>Is there anything I have to check?</p>