dns2.vps.net has no NS records.
NS records for this zone are defined at vps.net.
NS records for this zone are defined at vps.net.
Question and response
Question
dig dns2.vps.net. NS
Answer
The response has no answer records.
Authority
vps.net. 900 SOA dns1.vps.net. hostmaster.vps.net. 2026022603 7200 600 1728000 900
Additional
. 0 OPT ; payload 1280, xrcode 0, version 0, flags 0