f4.ods2.net has no NS records.
NS records for this zone are defined at ods2.net.
NS records for this zone are defined at ods2.net.
Question and response
Question
dig f4.ods2.net. NS
Answer
The response has no answer records.
Authority
ods2.net. 300 SOA ns1-05.azure-dns.com. azuredns-hostmaster.microsoft.com. 1 3600 300 2419200 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0