gistfile1.txt

upstream thin1 {
        server 127.0.0.1:3000;
}

server {
        listen   80;
        server_name  host1.some.wh;

        access_log  /var/log/nginx/host1.access.log;

        location / {
                proxy_pass http://thin1;
                break;
        }

        location / {
                set $memcached_key $uri;
                memcached_pass 127.0.0.1:11211;

                proxy_set_header X-Real-IP $remote_addr;
                proxy_set_header  X-Forwarded-For $proxy_add_x_forwarded_for;
                proxy_set_header Host $http_host;
                proxy_redirect off;

                default_type text/html;
                error_page 404 = /fallback;
        }

        location = /fallback {
                proxy_pass http://thin1;
        }
}