ns6.imsbiz.com has one IP number , which also has a corresponding reverse pointer. wvbizdns03.imsbiz.com point to the same IP. opg.hk, hkt.com, sehk.com, hkep.com, suep.com and at least 100 other hosts use this as a nameserver. imsbiz.com is a domain controlled by two nameservers at imsbiz.com themselves. They are on different IP networks. Incoming mail for imsbiz.com is handled by one mailserver having a total of two IP numbers. They are on the same IP network. ns6.imsbiz.com is hosted on a server in Hong Kong.