mailserver.mostcom.ru has no NS records.
NS records for this zone are defined at mostcom.ru.
NS records for this zone are defined at mostcom.ru.
Question and response
Question
dig mailserver.mostcom.ru. NS
Answer
The response has no answer records.
Authority
mostcom.ru. 3600 SOA ns.mostcom.ru. hostmaster.mostcom.ru. 2024011404 10800 1800 1209600 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0