Apex domains cannot have CNAME records.
Question and response
Question
dig hnet.RU. NS
Answer
hnet.RU. 1 NS ns2.nsk.ru.
hnet.RU. 1 NS ns5.nsk.ru.
hnet.RU. 1 NS ns.nsk.ru.
Authority
The response has no authority records.
Additional
ns.nsk.RU. 1 A 89.251.96.75
ns5.nsk.RU. 1 A 95.131.13.182
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0