mta2.dnmailer.net has no NS records.
NS records for this zone are defined at dnmailer.net.
NS records for this zone are defined at dnmailer.net.
Question and response
Question
dig mta2.dnmailer.net. NS
Answer
The response has no answer records.
Authority
dnmailer.net. 3600 SOA ns1.viidakko.fi. admin.dnsimple.com. 1727956589 86400 7200 604800 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0