Hello,

>"The file should be transferred to the nginx server."

This is the whole point.
With current configuration when I type curl --data-binary '@upload.txt' http://localhost/upload file is NOT transffered from client to server at all - "proxy_pass" is performed and I only get HTTP response 200.

When I change my configuration (by removing whole backend configuration (s2 block) and all proxy_* directives from s1) and type same command I get HTTP 405 Not Allowed or HTTP 301 Moved Permanently.

Let's ignore for the second size of my file in body. Maybe in this moment the right question is: what should I do to make my above curl command work?

Regards,
Dawid