mail.online.net has no NS records.
NS records for this zone are defined at online.net.
NS records for this zone are defined at online.net.
Question and response
Question
dig mail.online.net. NS
Answer
The response has no answer records.
Authority
online.net. 14400 SOA nsa.online.net. dnsmaster.te-dns.net. 2026030503 14400 3600 604800 14400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0