ns4.arbexti.com.br has no CNAME records.
Question and response
Question
dig ns4.arbexti.com.br. NS
Answer
The response has no answer records.
Authority
arbexti.com.br. 5208 SOA ns1.186-209-113-106.cprapid.com. webmaster.valuehost.com.br. 2026030403 3600 1800 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0