ns.noc.grnet.gr has no CNAME records.
Question and response
Question
dig ns.noc.grnet.gr. NS
Answer
The response has no answer records.
Authority
noc.grnet.gr. 100 SOA ns.noc.grnet.gr. admin.noc.grnet.gr. 2026013000 10800 3600 2419200 100
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0