title: Enable Authentication in Elasticsearch with docker environment variable
body: <p>I am using a Docker image of Elasticsearch v.6.2.4. My problem is that X-Pack is installed, but it is not asking for credentials.</p>
  <p>I know that X-Pack is installed as you can see below:</p>
  <p><img src="https://i.stack.imgur.com/9VaQS.png" alt="Screenshot of remark that X-Pack is installed." /></p>