ns1.sun.com has one IP number , but the reverse is cltea-ns-1.sun.com. ns1.eu.sun.com and cltea-ns-1.sun.com point to the same IP. sun.be, sun.de, sun.es, sun.fr, sun.cl and at least 100 other hosts use this as a nameserver. sun.com is a domain controlled by four nameservers at sun.com themselves. All of them are on different IP networks. Incoming mail for sun.com is handled by four mailservers having a total of six IP numbers. Some of them are on the same IP network. sun.com has one IP number. ns1.sun.com is hosted on a server in United States.