mx02.hoster.ru has no NS records.
NS records for this zone are defined at hoster.ru.
NS records for this zone are defined at hoster.ru.
Question and response
Question
dig mx02.hoster.ru. NS
Answer
The response has no answer records.
Authority
hoster.ru. 1800 SOA ns10.hoster.ru. support.hoster.ru. 3509107393 3600 300 604800 1800
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0