We pick d.root-servers.net, one of the 13 root servers (1), and ask it about cometco.com.vn and learn that vn is delegated to seven name servers (2), so we ask b.dns-servers.vn where we see a CNAME from cometco.com.vn to thongbao.vnnic.vn, so we have to start all over again. We already know that f.dns-servers.vn is authoritative for vn (3) and ask it about thongbao.vnnic.vn and learn that vnnic.vn is delegated to three name servers (4), so we ask dns2.vnnic.vn and get the following answer:
