spf2.as23951.net has no NS records.
NS records for this zone are defined at as23951.net.
NS records for this zone are defined at as23951.net.
Question and response
Question
dig spf2.as23951.net. NS
Answer
The response has no answer records.
Authority
as23951.net. 900 SOA ns-1720.awsdns-23.co.uk. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0