mail.PODOLSKNET.RU has no CNAME records.
Question and response
Question
dig mail.PODOLSKNET.RU. NS
Answer
The response has no answer records.
Authority
PODOLSKNET.RU. 1169 SOA ns1.PODOLSKNET.RU. info.navigatorlife.RU. 2026020500 28800 7200 1728000 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0