# NGINX - 502 Bad Gateway **URL:** \ **Category:** Technical Forums\ **Tags:** security, devops, application-delivery\ **Created:** [November 15, 2022, 6:09am UTC](https://community.f5.com/t/nginx-502-bad-gateway/70962 "2022-11-15T06:09:54Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Ashuda](https://avatars.discourse-cdn.com/v4/letter/a/db5fbb/32.png) [@Ashuda](https://community.f5.com/u/Ashuda)\ **Post date:** [November 15, 2022, 6:09am UTC](https://community.f5.com/t/nginx-502-bad-gateway/70962/1 "2022-11-15T06:09:54Z")
Hi everyone I have an application running successfully for almost couple of years. But suddenly I am getting the below error. The configuration files are untouched. After then only I tried updating the timeout parameters in config file from the ideas provided through blogs. but no luck. We have used NGINX mainly for reverse proxy, so i hope this is something that needs to be fixed from NGINX (May be IP Blocked. I’m not sure). I have also given below my config file for reference. Kindly guide me in resolving this issue. ![502-BadGateway.PNG](https://d20hrnpixdzcsd.cloudfront.net/original/2X/e/ec3b810c4e174f4d7ebbb88130b2aa55eddb019b.png) ```tcl worker_processes 1; events { worker_connections 1024; } http { include mime.types; default_type application/octet-stream; sendfile on; keepalive_timeout 320; server { listen 443 ssl; server_name www.xxxyyy.com; ssl_certificate C:/nginx/keys/zzzzz.pem; ssl_certificate_key C:/nginx/keys/yyyyy.key; location / { proxy_pass http://127.0.0.1:4446/; } error_page 500 502 503 504 /50x.html; location = /50x.html { root html; } } } ``` ---
**Author:** ![Daniel\_Wolf](https://d1p9zq3aats0t8.cloudfront.net/user_avatar/community.f5.com/daniel_wolf/32/1119_2.png) [@Daniel\_Wolf](https://community.f5.com/u/Daniel_Wolf)\ **Post date:** [November 15, 2022, 6:54pm UTC](https://community.f5.com/t/nginx-502-bad-gateway/70962/2 "2022-11-15T18:54:02Z")
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 ---
**Author:** ![Ashuda](https://avatars.discourse-cdn.com/v4/letter/a/db5fbb/32.png) [@Ashuda](https://community.f5.com/u/Ashuda)\ **Post date:** [November 18, 2022, 6:07am UTC](https://community.f5.com/t/nginx-502-bad-gateway/70962/3 "2022-11-18T06:07:22Z")
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 ? ---
**Author:** ![Daniel\_Wolf](https://d1p9zq3aats0t8.cloudfront.net/user_avatar/community.f5.com/daniel_wolf/32/1119_2.png) [@Daniel\_Wolf](https://community.f5.com/u/Daniel_Wolf)\ **Post date:** [November 18, 2022, 11:02am UTC](https://community.f5.com/t/nginx-502-bad-gateway/70962/4 "2022-11-18T11:02:19Z")
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](http://127.0.0.1:4446)) from the browser. Check Windows firewall rules.