Apex domains cannot have CNAME records.
Question and response
Question
dig dnsnode.net. NS
Answer
dnsnode.net. 5 NS nnp.dnsnode.net.
dnsnode.net. 5 NS nna.dnsnode.net.
dnsnode.net. 5 NS nnb.dnsnode.net.
dnsnode.net. 5 NS nnu.dnsnode.net.
Authority
The response has no authority records.
Additional
nna.dnsnode.net. 5 A 194.58.192.132
nnb.dnsnode.net. 5 A 194.58.193.132
nnp.dnsnode.net. 5 A 194.58.198.132
nnu.dnsnode.net. 5 A 185.42.137.132
nna.dnsnode.net. 5 AAAA 2a01:3f1:32:8000:0:0:0:53
nnb.dnsnode.net. 5 AAAA 2a01:3f1:432:8000:0:0:0:53
nnp.dnsnode.net. 5 AAAA 2a01:3f1:3032:8000:0:0:0:53
nnu.dnsnode.net. 5 AAAA 2a01:3f0:400:8000:0:0:0:32
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0