ns4.sweb.RU has no NS records.
NS records for this zone are defined at sweb.RU.
NS records for this zone are defined at sweb.RU.
Question and response
Question
dig ns4.sweb.RU. NS
Answer
The response has no answer records.
Authority
sweb.RU. 300 SOA ns1.sweb.RU. postmaster.sweb.RU. 2023050903 7200 3600 14400 300
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0