nginx Server Admin manual suggests disabling request buffering which will lead to problems

[haarp]

The current documentation for nginx suggests disabling fastcgi_request_buffering:

Setting this option to fastcgi_request_buffering off; in your nginx config might help with timeouts during the upload. Furthermore it helps if you’re running out of disc space on the tmp partition of your system.

However, this setting is dangerous and will lead to 0-byte files when using chunked uploads. See this issue.

The documentation should be adjusted accordingly. fastcgi_request_buffering should be kept on.

Cheers!