Apex domains cannot have CNAME records.
Question and response
Question
dig linkdsl.net. NS
Answer
linkdsl.net. 5 NS ns-94.awsdns-11.com.
linkdsl.net. 5 NS ns-192.awsdns-24.com.
linkdsl.net. 5 NS ns-446.awsdns-55.com.
linkdsl.net. 5 NS ns-1719.awsdns-22.co.uk.
Authority
The response has no authority records.
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0