mta1.pd.ipreo.com has no NS records.
NS records for this zone are defined at ipreo.com.
NS records for this zone are defined at ipreo.com.
Question and response
Question
dig mta1.pd.ipreo.com. NS
Answer
The response has no answer records.
Authority
ipreo.com. 900 SOA ns1.ihsmarkit.com. hostmaster.ihsmarkit.com. 2019121242 900 3600 2419200 900
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0