mxb.ASTRALINUX.RU has no NS records.
NS records for this zone are defined at ASTRALINUX.RU.
NS records for this zone are defined at ASTRALINUX.RU.
Question and response
Question
dig mxb.ASTRALINUX.RU. NS
Answer
The response has no answer records.
Authority
astralinux.ru. 3600 SOA ns1.yandexcloud.net. mx.cloud.yandex.net. 1 10800 900 604800 86400
Additional
. 0 OPT ; payload 1024, xrcode 0, version 0, flags 0