ns4.gcorelabs.net has no NS records.
NS records for this zone are defined at gcorelabs.net.
NS records for this zone are defined at gcorelabs.net.
Question and response
Question
dig ns4.gcorelabs.net. NS
Answer
The response has no answer records.
Authority
gcorelabs.net. 300 SOA gns1.gcdn.co. support.gcorelabs.com. 1739362137 5400 5400 1209600 300
Additional
. 0 OPT ; payload 1280, xrcode 0, version 0, flags 0