We pick d.root-servers.net, one of the 13 root servers (1), and ask it about eproc-lpse.pln.co.id and learn that id is delegated to four name servers (2), so we ask ns1.indo.net.id where we learn that pln.co.id is delegated to four name servers, including ns1.coz-u.net (3), so we ask that one and get the following answer: