cmx.gmo.jp has no NS records.
NS records for this zone are defined at gmo.jp.
NS records for this zone are defined at gmo.jp.
Question and response
Question
dig cmx.gmo.jp. NS
Answer
The response has no answer records.
Authority
gmo.jp. 1800 SOA ns1.cf.gmointernet.jp. dns.cloudflare.com. 2396877784 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0