How to proxy RDP via Nginx 远程桌面 rdp 使用 nginx 转发

Well actually you are right the http is the problem but not exactly that one in your code block. Lets explain it a bit:

In your nginx.conf file you have something similar to this:

http {  
    ...
    ...
    ...

    include /etc/nginx/conf.d/*.conf;
    include /etc/nginx/sites-enabled/*;
}

So everything you write in your conf files are inside this http block/scope. But rdp is not http is a different protocol.

The only workaround I know for nginx to handle this is to work on tcp level.

So inside in your nginx.conf and outside the http block you have to declare the stream block like this:

stream {
    # ...
    server {
        listen     80;
        proxy_pass 192.168.0.100:3389;
    }
}

With the above configuration just proxying your backend on tcp layer with a cost of course. As you may notice its missing the server_name attribute you can't use it in the stream scope, plus you lose all the logging functionality that comes on the http level.