title: zabbix after the frontend install finished, the index.php report 502 bad gateway
body: <p>Environment: ubuntu 14.04 and centos 7</p>
  
  <p>Problem description: I have already finished the front end installation. And the click go ahead, the page report error and 502 bad gate way.</p>
  
  <p><a href="https://i.stack.imgur.com/n7gke.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/n7gke.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/Dos4N.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Dos4N.png" alt="enter image description here"></a></p>
  
  <p>Can someone help me ???</p>