mx2.spb.avantel.ru has no NS records.
NS records for this zone are defined at spb.avantel.ru.
NS records for this zone are defined at spb.avantel.ru.
Question and response
Question
dig mx2.spb.avantel.ru. NS
Answer
The response has no answer records.
Authority
spb.avantel.ru. 3600 SOA ns1.spb.avantel.ru. noc.spb.avantel.ru. 2025102001 10800 3600 2419200 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0