Sky regularly pull IP addresses listed on our DNS servers and adds them to their block list. This block list is then used by an advanced proxy system that redirects any requests to the blacklisted IP addresses to a webserver that the ISP owns which returns a blocked page message,” YIFY explains.
Therefore, when YIFY began using CloudFlare servers in Australia, Sky pulled these IP addresses and blocked them in the mistaken belief that they were YIFY’s. Since Imgur uses the same IP addresses, Sky’s automated blocking took the site offline, to the huge disappointment of countless customers.
via Imgur Wiped Out By Sky Broadband Torrent Site Blocking | TorrentFreak.