[nginx] nginx: [emerg] "server" directive is not allowed here

Example valid nginx.conf for reverse proxy; In case someone is stuck like me. where 10.x.x.x is the server where you are running the nginx proxy server and to which you are connecting to with the browser, and 10.y.y.y is where your real web server is running

events {
  worker_connections  4096;  ## Default: 1024
}
http {
 server {
   listen 80;
   listen [::]:80;

   server_name 10.x.x.x;
 
   location / {
       proxy_pass http://10.y.y.y:80/;
       proxy_set_header Host $host;
   }
 }
}

Here is the snippet if you want to do SSL pass through. That is if 10.y.y.y is running a HTTPS webserver. Here 10.x.x.x, or where the nignx runs is listening to port 443, and all traffic to 443 is directed to your target web server

events {
  worker_connections  4096;  ## Default: 1024
}

stream {
  server {
    listen     443;
    proxy_pass 10.y.y.y:443;
  }
}

and you can serve it up in docker too

 docker run --name nginx-container --rm --net=host   -v /home/core/nginx/nginx.conf:/etc/nginx/nginx.conf nginx