DNS delegation of facebook.dk updated: May 19, 2013 4:13:49 AM
We pick e.root-servers.net, one of the 13 root servers (1), and ask it about facebook.dk and learn that dk is delegated to six name servers (2), so we ask b.nic.dk where we learn that facebook.dk is delegated to two name servers, including a.ns.facebook.com (3), so we ask that one and get the following answer:
The two IP numbers 2a03:2880:2110:df01:face:b00c::8 and 188.8.131.52 together
Most of the about eighty host names that point to IP group 1 use the two name servers a and b.ns.facebook.com together, hereafter referred to as "name server group 1", (example: facebook.ca, facebook.cl and facebook.co ). Worth noting is that eleven percent of the domains that use name server group 1 point to IP group 1.