title: AWS HTTP API Gateway 503 Service Unavailable
body: <p>I have an HTTP API Gateway with a HTTP Integration backend server on EC2. The API has lots of queries during the day and looking at the logs i realized that the API is returning sometimes a 503 HTTP Code with a body:</p>
  <pre><code>{ &quot;message&quot;: &quot;Service Unavailable&quot; }
  </code></pre>
  <p>When i found out this, i tried the API and running the HTTP requests many times on Postman, when i try twenty times i get at least one 503.</p>
  <p>I then thought that the HTTP Integration Server was busy but the server is not loaded and i tried going directly to the HTTP Integration Server and i get 200 responses all the times.</p>
  <p>The timeout parameter is set to 30000ms and the endpoint average response time is 200ms so timeout is not a problem. Also the HTTP 503 is not after 30 seconds of the request but instantly.</p>
  <p>Can anyone help me?</p>
  <p>Thanks</p>