smtp-5-net.mm.fr.colt.net has no NS records.
NS records for this zone are defined at mm.fr.colt.net.
NS records for this zone are defined at mm.fr.colt.net.
Question and response
Question
dig smtp-5-net.mm.fr.colt.net. NS
Answer
The response has no answer records.
Authority
mm.fr.colt.net. 3600 SOA ns0.coltfrance.com. hostmaster.coltfrance.com. 2017020800 21600 3600 604800 3600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0