mx.securemx.jp has no NS records.
NS records for this zone are defined at securemx.jp.
NS records for this zone are defined at securemx.jp.
Question and response
Question
dig mx.securemx.jp. NS
Answer
The response has no answer records.
Authority
securemx.jp. 3600 SOA dns0.iij.ad.jp. postmaster.iij.ad.jp. 100651 3600 1800 3600000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0