ns1.dmz.inxmail.de.inxserver.com has no CNAME records.
Question and response
Question
dig ns1.dmz.inxmail.de.inxserver.com. NS
Answer
The response has no answer records.
Authority
inxserver.com. 2919 SOA ns1.dmz.inxmail.de.inxserver.com. hostmaster.inxmail.de. 2026022301 3600 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0