mx2.astranet.RU has no CNAME records.
Question and response
Question
dig mx2.astranet.RU. NS
Answer
The response has no answer records.
Authority
astranet.RU. 224 SOA ns1.astranet.RU. smena.astranet.RU. 2026021800 3600 900 1209600 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0