Summary
dns.net4b.pt has one IP number , which also has a corresponding reverse pointer.
cpk.pt,
cuf.pt,
way.pt,
mrb.pt,
isp.pt and at least 100 other hosts use this as a nameserver.
net4b.pt is delegated to two nameservers, however both delegated nameservers are missing in the zone and two other nameservers are listed instead. Two nameservers have the same IP number. All of them are on the same IP network. Incoming mail for
net4b.pt is handled by one mailserver at
net4b.pt themselves.
dns.net4b.pt is hosted on a server in Portugal.