Summary
mx.is.nl has one IP number , but the reverse is
mail.overalenaltijd.nl.
pop.is.nl,
mail.sdn.nl,
mail.idh.nl,
mail.shcn.nl,
mail.crux.nl and at least 43 other hosts cnames to this hostname.
mx4.is.nl,
mx2.is.nl,
mx1.is.nl,
mx3.is.nl,
fe001.is.nl and at least twelve other hosts point to the same IP.
a1.nu,
21c.nl,
i-3.nl,
lcn.nl,
vix.nu and at least 100 other hosts use this as a mailserver.
is.nl is a domain controlled by two nameservers at
is.nl themselves. They are on different IP networks. Incoming mail for
is.nl is handled by one mailserver at
overalenaltijd.nl.
is.nl has one IP number.
mx.is.nl is hosted on a server in Netherlands.