mpgent.dioss.com has no NS records.
NS records for this zone are defined at dioss.com.
NS records for this zone are defined at dioss.com.
Question and response
Question
dig mpgent.dioss.com. NS
Answer
The response has no answer records.
Authority
dioss.com. 3600 SOA axfr.dnsimple.com. admin.dnsimple.com. 1521450094 86400 7200 604800 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0