mx.nether.net has no CNAME records.
Question and response
Question
dig mx.nether.net. NS
Answer
The response has no answer records.
Authority
nether.net. 1097 SOA puck.nether.net. jared.puck.nether.net. 2025090101 28800 7200 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0