my dedicated server stopped responding to requests on port 80 today out of sudden, i havent touched anything in more than a month. its ubuntu 10, varnish + nginx + php-fpm, only 1 website. load is at 0. i messaged my ISP if they changed something but no reply yet. i tried to access the site via http://web-sniffer.net/ and it times out on port 80, but if i connect directly to nginx on port 8080 it loads just fine. for normal users, it doesnt load on neither of these in normal browser. any tips what to check or what could be causing this?