Problem with XBT?

Question

Nginx

There is a main server on which a bunch of sites are spinning + xbt, in order to hide from prying eyes the real ip of the server, I bought another server and made my dns and redirect to the main server with nginx on it

server {
server_name hot-torrent.org www.hot-torrent.org;
listen IP_gateway;
location / {
proxy_pass http://primary_server_ip :81;
proxy_redirect http://primary_server_ip :81/ /;
proxy_set_header Host $host;
proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
proxy_set_header X-Forwarded-Proto $scheme;
proxy_set_header X-Real-IP $remote_addr;
}
include /usr/local/ispmgr/etc/nginx.inc;
}

Yes, maybe not everything is written perfectly, but it works perfectly for me, but what's the problem?

PS1: + The problem with the fact that all users have an ip address of the gateway