Nginx在proxy_pass之后删除内容长度的HTTP标头

Question

I have a problem that nginx removes the content-length header after the proxy pass. the application back-end sends a gzip stream but specifies the content length.
NGINX changes the type content-type to chunked and removes the content length header.
This is not acceptable for the app since it is read not by the browser but by an proprietary app that requires the content-legth to be specified.
After specified chunked_transfer_encoding off; it stops adding the content type header but still removes the content length. How to disable any header modifications in nginx?
The confing:

upstream backend {
      server 127.0.0.1:9090;
}


server {
root /usr/share/nginx/www;
index index.html index.htm;

chunked_transfer_encoding       off;

        location / {
           proxy_pass  http://backend;
           proxy_next_upstream error timeout invalid_header http_500 http_502 http_503 http_504;
           proxy_redirect off;
           proxy_buffering off;
           proxy_set_header        Host            $host;
           proxy_set_header        X-Real-IP       $remote_addr;
           proxy_set_header        X-Forwarded-For $proxy_add_x_forwarded_for;
       }
}

Answer 1

This was a known bug in nginx in the past. Update to the latest build.

http://forum.nginx.org/read.php?2,216085,216085#msg-216085