ai.nih.gov has no NS records.
NS records for this zone are defined at nih.gov.
NS records for this zone are defined at nih.gov.
Question and response
Question
dig ai.nih.gov. NS
Answer
The response has no answer records.
Authority
nih.gov. 900 SOA nihblox6.nih.gov. hostmaster.nih.gov. 904250 10800 1080 2592000 900
Additional
. 0 OPT ; payload 1220, xrcode 0, version 0, flags 0