mx.rootnet.nl has no NS records.
NS records for this zone are defined at rootnet.nl.
NS records for this zone are defined at rootnet.nl.
Question and response
Question
dig mx.rootnet.nl. NS
Answer
The response has no answer records.
Authority
rootnet.nl. 555 SOA nsauth.myrootnet.com. root.rootnet.nl. 2026022302 14400 3600 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0