We pick h.root-servers.net, one of the 13 root servers (1), and ask it about yahoo.com.ar and learn that ar is delegated to five name servers (2), so we ask ctina.ar where we learn that yahoo.com.ar is delegated to four name servers, including ns5.yahoo.com (3), so we ask that one and get the following answer:
Yahoo.com.ar is a domain controlled by four domain name servers at yahoo.com. All four of them are on different IP networks. Incoming mail for yahoo.com.ar is handled by three mail servers at yahoodns.net having a total of 16 IP numbers. There are 32 duplicated IP numbers. Some of them are on the same IP network. Yahoo.com.ar has two IP numbers (68.180.206.184, 98.139.102.145). Both are on different IP networks.
The five name servers ns1, ns2, ns3, ns4 and ns5.yahoo.com together
Three quarter of the more than two hundred domains that use name server group 1 point to IP group 1 (example: cgi2-yahoo.com, dlsyahoo.com and emailyahoomail.com ). Worth noting is that most of the host names that point to IP group 1 use name server group 1.
