Summary
ns.hsl.com has one IP number , which also has a corresponding reverse pointer.
2-u.de,
rhb.de,
p90.de,
dtmp.de,
hsl.com and at least 100 other hosts use this as a nameserver.
hsl.com is delegated to two nameservers, however one extra nameserver is listed in the zone. All nameservers are at
hsl.com themselves. Two of them are on the same IP network. Incoming mail for
hsl.com is handled by three mailservers also at
hsl.com. Two mailservers have the same IP number. Some of them are on the same IP network.
hsl.com has one IP number.
ns.hsl.com is hosted on a server in Germany.