ns.vas-hosting.com has no CNAME records.
Question and response
Question
dig ns.vas-hosting.com. NS
Answer
The response has no answer records.
Authority
vas-hosting.com. 3126 SOA ns.vas-hosting.cz. info.vas-hosting.cz. 2512310823 28800 600 2419200 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0