nginx_balancer_vhost

upstream backend {
	server backend1.example.com;
	server backend2.example.com;
	server 192.0.0.1 backup;
}

server {
	listen 80;



	server_name _;

	location / {
	    proxy_set_header Host $host;
	    proxy_set_header X-Real-IP $remote_addr;
	    proxy_pass http://backend;
	}

}