Apex domains cannot have CNAME records.
Question and response
Question
dig linux-hungary.eu. NS
Answer
linux-hungary.eu. 5 NS ns.skylinux.org.
linux-hungary.eu. 5 NS ns1.skylinux.org.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0