xen.nsys.cz has no NS records.
NS records for this zone are defined at nsys.cz.
NS records for this zone are defined at nsys.cz.
Question and response
Question
dig xen.nsys.cz. NS
Answer
The response has no answer records.
Authority
nsys.cz. 3600 SOA ans.nsys.cz. admin.nsys.cz. 2026021001 14400 3600 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0