ns2.edgedns.RU has no CNAME records.
Question and response
Question
dig ns2.edgedns.RU. NS
Answer
The response has no answer records.
Authority
edgedns.RU. 300 SOA ns1.edgedns.ru. support.edgecenter.ru. 1759150610 5400 3600 1209600 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0