Apex domains cannot have CNAME records.
Question and response
Question
dig vlq8.iliad.fr. NS
Answer
vlq8.iliad.fr. 5 NS ns0.iliad.fr.
vlq8.iliad.fr. 5 NS ns2.iliad.fr.
vlq8.iliad.fr. 5 NS ns1.iliad.fr.
Authority
The response has no authority records.
Additional
ns1.iliad.fr. 5 A 212.27.33.3
ns2.iliad.fr. 5 A 212.83.164.80
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0