bd.online.net.br has no CNAME records.
Question and response
Question
dig bd.online.net.br. NS
Answer
The response has no answer records.
Authority
online.net.br. 10 SOA ns01.online.net.br. noc\@online.net.br. 202412943 3600 1800 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0