server04.mailgrid.com.br has no NS records.
NS records for this zone are defined at mailgrid.com.br.
NS records for this zone are defined at mailgrid.com.br.
Question and response
Question
dig server04.mailgrid.com.br. NS
Answer
The response has no answer records.
Authority
mailgrid.com.br. 900 SOA ns-889.awsdns-47.net. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0