mxsend.ertelecom.ru has no NS records.
NS records for this zone are defined at ertelecom.ru.
NS records for this zone are defined at ertelecom.ru.
Question and response
Question
dig mxsend.ertelecom.ru. NS
Answer
The response has no answer records.
Authority
ertelecom.ru. 3600 SOA ns8.ertelecom.ru. noc.ertelecom.ru. 2026022001 86400 1800 604800 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0