Why can nginx load balancer break page output?

Question

Nginx

Apache and nginx back-servers
In the config only
client_max_body_size 1024M client_body_buffer_size
4M is specified from the restrictions .

Answer 1

сталкивался с таким когда на сервере раздел /tmp был не в памяти, а на диске, и кончилось место. нгинкс в /tmp куски больших страниц пишет.

Answer 2

What about the logs? It can't be empty.
PS And the back case does not send the incorrect Content-Length?

Answer 3

You should pay attention to the buffer size proxy_buffer_size if Nginx is used as a proxy server:
https://ruhighload.com/%D0%9E%D1%88%D0%B8%D0%B1%D0...

http {
  proxy_buffer_size   64k;
  proxy_buffers   4 64k;
  proxy_busy_buffers_size   64k;
}