mail.il0.ch has no CNAME records.
Question and response
Question
dig mail.il0.ch. NS
Answer
The response has no answer records.
Authority
il0.ch. 1800 SOA ns1.fima-hosting.ch. helpdesk.fima.ch. 2020093792 21600 10800 1209600 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0