mx01.vargonen.net has no NS records.
NS records for this zone are defined at vargonen.net.
NS records for this zone are defined at vargonen.net.
Question and response
Question
dig mx01.vargonen.net. NS
Answer
The response has no answer records.
Authority
vargonen.net. 1800 SOA brit.ns.cloudflare.com. dns.cloudflare.com. 2397960314 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0