Multiple Wan IP Addresses, Single LAN IP Address

[reference123]

We are using NGINX .7.6 as a reverse proxy to an IIS webserver.  We are trying to serve our images from a separate domain and IP that proxies to the same IIS root as the primary website.  Both IP addresses are on the same subnet.  The primary domain is on 67.111.111.1 and the image domain is on 67.111.111.12.  

The NGINX config related to these two sites is as follows - 

upstream primary_com {
		server		10.1.1.2 weight=10 max_fails=3 fail_timeout=30s;         
		server		10.1.1.1 weight=1 backup;
         
	 
    }

    upstream primary_com_ssl {
		server		10.1.1.2:443 weight=10 max_fails=3 fail_timeout=30s;         
		server		10.1.1.1:443 weight=1 backup;
         
    }

    
    server {
         listen		80;
         server_name	67.111.111.1
			primary.com 
                        www.primary.com;
			
         
         
	       
         access_log	/var/log/nginx/primary.access.log;

	
       
        location / {      	
		proxy_pass	http://primary_com;
		

        }

		

    }


    
    server {
         listen			443;
         server_name		67.111.111.1
				primary.com
				www.primary.com;
       
         access_log		/var/log/nginx/primary.ssl.access.log;
	 error_log		/var/log/nginx/primary.ssl.error.log;

         ssl			on;
         ssl_certificate 	/etc/ssl/primary/disccert.pem;
         ssl_certificate_key	/etc/ssl/primary/disckey.pem;
	 

	ssl_ciphers  ALL:!ADH:RC4+RSA:+HIGH:+MEDIUM:-LOW:-SSLv2:-EXP;
	ssl_protocols SSLv3 TLSv1;
	

         location / {
              proxy_pass	https://primary_com_ssl;
         }
         

    }

upstream images_com {
       server          10.1.1.2 weight=10 max_fails=3 fail_timeout=30s;
       server          10.1.1.1 weight=1 backup;
}

server {
       listen          80;
       server_name      67.111.111.12
                               www.images.com
                               1.images.com
                               2.images.com
                               3.images.com;

       access_log      /var/log/nginx/images.access.log;
     

       ## Only requests to our Host are allowed
       if ($host !~ ^(images.com|www.images.com|1.images.com|2.images.com|3.images.com|4.images.com)$ ) {
               return 444;
		}

       
	  location ~* (\.jpg|\.png|\.gif|\.css)$ {

               valid_referers
                       none
                       blocked
                       images.com
                       www.images.com
                       images.com
                       www.images.com
                       1.images.com
                       2.images.com
                       3.images.com
                       4.images.com;

               if ($invalid_referer) {
                       return 444;
               }

		               
		
		proxy_cache_valid 200 301 302 1480m;
		expires	10d;
		proxy_cache dci;
		proxy_cache_use_stale	error timeout invalid_header updating;
		proxy_pass     http://images_com;
    }       

When images are pulled through the images domain the rendering of the images slows considerably.  I am sure it is not related to the line speed, latency, or dns servers.  It appears there is something happening on the proxy side either in pulling the images from the backend server or in its attempt to respond to the outside request.  Is there anything that needs to be done in the upstream or listen section to make this process efficient?

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,97002,97002#msg-97002