ntppool2.time.nl has no NS records.
NS records for this zone are defined at time.nl.
NS records for this zone are defined at time.nl.
Question and response
Question
dig ntppool2.time.nl. NS
Answer
The response has no answer records.
Authority
time.nl. 300 SOA ns1.sidnlabs.nl. hostmaster.sidn.nl. 2799 14400 3600 604800 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0