db.omkc.ru has no CNAME records.
Question and response
Question
dig db.omkc.ru. NS
Answer
The response has no answer records.
Authority
omkc.ru. 1451 SOA ns.omkc.ru. root.ns.omkc.ru. 2026021704 3600 900 360000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0