ns.keymachine.de has no CNAME records.
Question and response
Question
dig ns.keymachine.de. NS
Answer
The response has no answer records.
Authority
keymachine.de. 4620 SOA ns.keymachine.de. root.ns.keymachine.de. 2501161120 7200 2400 1209600 84600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0