hs30.drive.ne.jp has one IP number , which also has a corresponding reverse pointer. w39.net, jetty.cx, hr-dc.com, otagai.jp, fesol.net and at least 49 other hosts point to the same IP. drive.ne.jp is a domain controlled by two nameservers at drive.ne.jp themselves. They are on different IP networks. Incoming mail for drive.ne.jp is handled by one mailserver having a total of two IP numbers. They are on different IP networks. drive.ne.jp has one IP number. hs30.drive.ne.jp is hosted on a server in Japan.