anchor.diff:      <td> Platform</td>
       <td> Logs with error remote <code>error: tls: handshake failure</code> and <code>backend_tls_handshake_failed</code> metric increments</td>
     </tr>
  -  <tr>  
  +  <tr>
       <td>ExpiredOrNotYetValidCertFailure</td>
       <td> 502</td>
       <td> Yes</td>
  
positive.code:          Gorouter tracks <code>502</code> errors with the <code>gorouter.bad_gateways</code> metric.
           For more information, see <a href="<%= vars.gorouter_metrics_link %>">Router Error: 502 Bad Gateway</a>.
           </td>
    </tr> 
  </table>  
  
  
  ## <a id="app-errors"></a>Diagnose App Errors
  
negative.code:     <td>Yes</td>
      <td>Platform</td>
      <td>Logs with error <code>x509: certificate is valid for <x> not <y></code><br/> or <code>backend_invalid_id</code> metric increments</td>
    </tr>
    <tr>
      <td>UntrustedCert</td>
      <td>526</td>
      <td>Yes</td>
      <td>Platform</td>
      <td>Logs with error prefix <code>x509: certificate signed by unknown authority</code> or <code>backend_invalid_tls_cert</code> metric increments</td>
    </tr>
    <tr>
      <td>RemoteFailedCertCheck</td>
      <td>496</td>
      <td>Yes</td>
  