mx2.coprosys.cz has no NS records.
NS records for this zone are defined at coprosys.cz.
NS records for this zone are defined at coprosys.cz.
Question and response
Question
dig mx2.coprosys.cz. NS
Answer
The response has no answer records.
Authority
coprosys.cz. 360 SOA nsa.coprosys.cz. hostmaster.coprosys.cz. 2012110100 10800 3600 2419200 360
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0