s3.valfman.ru has no NS records.
NS records for this zone are defined at valfman.ru.
NS records for this zone are defined at valfman.ru.
Question and response
Question
dig s3.valfman.ru. NS
Answer
The response has no answer records.
Authority
valfman.ru. 1800 SOA ed.ns.cloudflare.com. dns.cloudflare.com. 2395636588 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0