mail.beta.uzsci.net has no CNAME records.
Question and response
Question
dig mail.beta.uzsci.net. NS
Answer
The response has no answer records.
Authority
beta.uzsci.net. 4074 SOA ns1.beta.uzsci.net. mskopytov.yandex.com. 2026021204 10800 3600 1209600 10800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0