tuvok.supramail.com.br has no NS records.
NS records for this zone are defined at supramail.com.br.
NS records for this zone are defined at supramail.com.br.
Question and response
Question
dig tuvok.supramail.com.br. NS
Answer
The response has no answer records.
Authority
supramail.com.br. 900 SOA ns-1933.awsdns-49.co.uk. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0