mx.irbrandpromos.com has no NS records.
NS records for this zone are defined at irbrandpromos.com.
NS records for this zone are defined at irbrandpromos.com.
Question and response
Question
dig mx.irbrandpromos.com. NS
Answer
The response has no answer records.
Authority
irbrandpromos.com. 3600 SOA dns.irbrandpromos.com. hostmaster.irbrandpromos.com. 1897282685 43200 3600 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0