mail.ruedudomaine.com has no NS records.
NS records for this zone are defined at ruedudomaine.com.
NS records for this zone are defined at ruedudomaine.com.
Question and response
Question
dig mail.ruedudomaine.com. NS
Answer
The response has no answer records.
Authority
ruedudomaine.com. 1800 SOA eric.ns.cloudflare.com. dns.cloudflare.com. 2399189680 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0