mx.fbdns.nl has two IP numbers. They are on the same IP network. mx.skg.nl, mx.porn.nl, mx.ipact.nl, mx.tintel.nl, mx.funbit.nl and at least 69 other hosts point to the same IP. fbdns.nl use this as a mailserver. fbdns.nl is a domain controlled by two nameservers at fbdns.nl themselves. They are on the same IP network. Incoming mail for fbdns.nl is handled by one mailserver having a total of two IP numbers. They are on the same IP network. mx.fbdns.nl is hosted on two servers in Netherlands.