go
lms.your-server.de has one IP number , which also has a corresponding reverse pointer. hetzner.de and your-server.de use this as a mailserver. your-server.de is a domain controlled by three nameservers. All of them are on different IP networks. Incoming mail for your-server.de is handled by one mailserver at your-server.de themselves. lms.your-server.de is hosted on a server in Germany.

lms.your-server.de
a records
 
+ 213.133.106.252 213.133.96.0/19 AS24940 -
+ --- -

your-server.de
ns-soa records
ns1.your-server.de
+ 213.133.106.251 213.133.96.0/19 AS24940 -
+ --- -
ns records
ns.second-ns.com
+ 213.239.204.242 213.239.192.0/18 AS24940 -
+ --- -
ns1.your-server.de
+ 213.133.106.251 213.133.96.0/19 AS24940 -
ns3.second-ns.de
+ 193.47.99.4 193.47.99.0/24 AS34011 -
mx records
lms.your-server.de
+ 213.133.106.252 213.133.96.0/19 AS24940 -
+ --- -
ip numbers of host
213.133.106.252
ptrs of ip numbers
lms.your-server.de
ip numbers using ptr to this host
213.133.106.252
domains using this as mailserver
hetzner.de
your-server.de