mx.maildeliver.jp has no NS records.
NS records for this zone are defined at maildeliver.jp.
NS records for this zone are defined at maildeliver.jp.
Question and response
Question
dig mx.maildeliver.jp. NS
Answer
The response has no answer records.
Authority
maildeliver.jp. 3600 SOA ns1.gmointernet.com. hostmaster.gmointernet.com. 2025013103 1800 900 604800 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0