30.1-94.47.193.165.in-addr.arpa has no NS records.
NS records for this zone are defined at 1-94.47.193.165.in-addr.arpa.
NS records for this zone are defined at 1-94.47.193.165.in-addr.arpa.
Question and response
Question
dig 30.1-94.47.193.165.in-addr.arpa. NS
Answer
The response has no answer records.
Authority
1-94.47.193.165.in-addr.arpa. 3600 SOA ns1.silverpop.com. dnsadmin.silverpop.com. 2015060201 86400 7200 604800 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0