Those Internet “experts”, Eircom, finally confessed that they were victims of a DNS attack called cache poisoning. When your client goes to your ISP’s DNS server to convert http://www.honestjoescars.com into an IP address your DNS server might need to go to another DNS server to do the job. It will get the result, cache it and then pass the result back to you. It might hold that cached lookup for 24 hours and all subsequent client requests for http://www.honestjoescars.com will get that cached result.
Someone planted poison cache results on the Eircom DNS servers. When Eircom’s customers tried to browse certain sites they were sent elsewhere … to the sort of site you might not want to go to. Eircom fervently denied there was an attack. Everything was fine. But customers who changed their TCP settings to use the OpenDNS servers had no issues. Strange, eh?
Siliconrebuplic posted the news.