ns1.namesserver.net has no CNAME records.
Question and response
Question
dig ns1.namesserver.net. NS
Answer
The response has no answer records.
Authority
namesserver.net. 8087 SOA ns1.nsserve.de. ns1.nsserve.de. 2003071821 40000 7200 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0