Apex domains cannot have CNAME records.
Question and response
Question
dig ip.frontiernet.net. NS
Answer
ip.frontiernet.net. 4 NS auth.roch.ny.frontiernet.net.
ip.frontiernet.net. 4 NS auth.frontiernet.net.
ip.frontiernet.net. 4 NS auth.asbn.va.frontiernet.net.
ip.frontiernet.net. 4 NS auth.larc.ca.frontiernet.net.
Authority
The response has no authority records.
Additional
auth.asbn.va.frontiernet.net. 3 A 74.46.42.179
auth.roch.ny.frontiernet.net. 3 A 50.48.212.201
auth.frontiernet.net. 3 A 74.40.74.20
auth.asbn.va.frontiernet.net. 3 AAAA 2001:1960:20:2030:400:0:0:179
auth.roch.ny.frontiernet.net. 3 AAAA 2001:1960:20:1030:400:0:0:201
auth.frontiernet.net. 3 AAAA 2001:1960:0:0:0:0:0:20
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0