mex.clara.ad.jp has no NS records.
NS records for this zone are defined at clara.ad.jp.
NS records for this zone are defined at clara.ad.jp.
Question and response
Question
dig mex.clara.ad.jp. NS
Answer
The response has no answer records.
Authority
clara.ad.jp. 1800 SOA gabe.ns.cloudflare.com. dns.cloudflare.com. 2397123728 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0