17840.whserv.de has no CNAME records.
Question and response
Question
dig 17840.whserv.de. NS
Answer
The response has no answer records.
Authority
whserv.de. 2484 SOA ns1.nshost2.de. hostmaster.webhostone.de. 2011050169 10800 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0