ns2.ionic.de has no CNAME records.
Question and response
Question
dig ns2.ionic.de. NS
Answer
The response has no answer records.
Authority
ionic.de. 2665 SOA ns1.ionic.de. ionic.ionic.de. 2025122900 3600 1800 1500000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0