ns.sovintel.ru has no CNAME records.
Question and response
Question
dig ns.sovintel.ru. NS
Answer
The response has no answer records.
Authority
sovintel.ru. 2932 SOA ns1.gldn.net. dnsmaster.gldn.net. 2025121701 28800 1800 3600000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0