title: how to debug symfony error "Untrusted Host" in production
body: <h1>problem :</h1>
  
  <p>Running symfony 3.4, I just preemptively took a look at symfony's logs and seen some strange errors :</p>
  
  <blockquote>
    <p>request.ERROR: Uncaught PHP Exception Symfony\Component\HttpKernel\Exception\BadRequestHttpException: "Untrusted Host "52.47.154.91"</p>
  </blockquote>
  
  <p>It's strange because I it is not the IP of my server...</p>
  
  <h1>question :</h1>
  
  <p>How would you investigate this? </p>
  
  <p>=> I think that I need more details in the log, but I don't know how to make monolog be more verbose on this error only</p>
  
  <hr>
  
  <p>complementary information :
  I'm hosted on AWS I know thaht need some special tuning, but I think that my app.php is well configured for running behind an ELB:</p>
  
  <pre><code>Request::setTrustedProxies(
  // trust *all* requests
      array('127.0.0.1', $request-&gt;server-&gt;get('REMOTE_ADDR')),
      Request::HEADER_X_FORWARDED_AWS_ELB
  );
  </code></pre>
  
  <p>and The IP that is loggued is the IP of the ELB (load balancer)</p>