502 Bad Gateway django nginx + gunicorn

Question

I am using post request to load a big amount of data from user input (textarea) to the database(18k lines) And I get the 502 Bad Gateway error

When I print sudo nano /var/log/nginx/error.log I get this:

2018/09/06 10:21:04 [alert] 19688#19688: *3 open socket #22 left in connection 4
2018/09/06 10:21:04 [alert] 19688#19688: aborting
2018/09/06 11:04:32 [error] 20076#20076: *14 upstream prematurely closed connection while reading response header from upstream, client: 95.1$

This is only on my production server (nginx + gunicorn + postgres), on my dev server it works great.

What do I do?

I have also

Answer 1

Increasing timeout in gunicorn helped to solve the issue