mail.montanadsl.net has no NS records.
NS records for this zone are defined at montanadsl.net.
NS records for this zone are defined at montanadsl.net.
Question and response
Question
dig mail.montanadsl.net. NS
Answer
The response has no answer records.
Authority
montanadsl.net. 1800 SOA etienne.ns.cloudflare.com. dns.cloudflare.com. 2395401665 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0