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Daniel_Wolf's avatar
Daniel_Wolf
Icon for MVP rankMVP
Nov 15, 2022

Hi Ashuda,

502 Bad Gateway is a generic error. Probably you can learn more looking at the NGINX error log.
A couple of reasons could be:

  • Backend service failed
  • High load on the server
  •  Service port of backend service blocked
  • Bug in the backend service

Usually NGINX shows 502 when it has a problem connecting to the backend service. Try to start your troubleshooting in this direction.

KR
Daniel

  • Ashuda's avatar
    Ashuda
    Icon for Altostratus rankAltostratus
    Nov 18, 2022

    Hi Daniel_Wolf 

    Thank you very much for the reply. In my first level of troubleshooting, I don't see any bugs or service getting failed from the back-end. Regarding the below mentioned points

    • High load on the server
    • Service port of backend service blocked

    I can check whether the service port is blocked from my end. But I have few questions.

    • How can we confirm if there is high load on server in NGINX ?
    • Is there any chance that my server IP/Port getting blocked by NGINX since it acts a reverse proxy ?
    • Apart from NGINX config file. Do I need to check anything on NGINX side ? 
    • Daniel_Wolf's avatar
      Daniel_Wolf
      Icon for MVP rankMVP
      Nov 18, 2022

      Since your config file says C:\nginx\, I guess you are running NGINX on a Windows box.
      Just take a look at Task Manager to see what processes are there and how much CPU / memory is consumed.

      Check that you can access the backend (http://127.0.0.1:4446) from the browser.

      Check Windows firewall rules.