ns2.yjs-cdn.com has no NS records.
NS records for this zone are defined at yjs-cdn.com.
NS records for this zone are defined at yjs-cdn.com.
Question and response
Question
dig ns2.yjs-cdn.com. NS
Answer
The response has no answer records.
Authority
yjs-cdn.com. 300 SOA ns1.yjs-cdn.com. dns.yjs-cdn.com. 1470920182 1800 900 604800 300
Additional
The response has no additional records.