dns.shadhinux.com has no NS records.
NS records for this zone are defined at shadhinux.com.
NS records for this zone are defined at shadhinux.com.
Question and response
Question
dig dns.shadhinux.com. NS
Answer
The response has no answer records.
Authority
shadhinux.com. 900 SOA ns-632.awsdns-15.net. awsdns-hostmaster.amazon.com. 1 7200 900 1209600 86400
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0