hosting.convex-tagil.ru has no MX records.
Question and response
Question
dig hosting.convex-tagil.ru. MX
Answer
The response has no answer records.
Authority
hosting.convex-tagil.ru. 3600 SOA ns.convex-tagil.ru. init.convex-tagil.ru. 2017091500 28800 7200 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0