mx.vnptemail.vn has no NS records.
NS records for this zone are defined at vnptemail.vn.
NS records for this zone are defined at vnptemail.vn.
Question and response
Question
dig mx.vnptemail.vn. NS
Answer
The response has no answer records.
Authority
vnptemail.vn. 3600 SOA ns1.vdconline.vn. vdconline.tld. 2026021164 28800 7200 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0