mail3.celeste.fr has no CNAME records.
Question and response
Question
dig mail3.celeste.fr. NS
Answer
The response has no answer records.
Authority
celeste.fr. 624 SOA ns1.celeste.fr.celeste.fr. support.celeste.fr. 2026030509 3600 900 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0