cdn-k8s-master2.spb.CDN.GbLNET.ru has no CNAME records.
Question and response
Question
dig cdn-k8s-master2.spb.CDN.GbLNET.ru. NS
Answer
The response has no answer records.
Authority
CDN.GbLNET.ru. 10787 SOA localhost. root.localhost. 2026020601 604800 86400 2419200 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0