ns4.byet.org has no CNAME records.
Question and response
Question
dig ns4.byet.org. NS
Answer
The response has no answer records.
Authority
byet.org. 2148 SOA ns1.byet.org. support.byet.org. 2010123002 28800 7200 604800 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0