ns1.houfek.cz has no NS records.
NS records for this zone are defined at houfek.cz.
NS records for this zone are defined at houfek.cz.
Question and response
Question
dig ns1.houfek.cz. NS
Answer
The response has no answer records.
Authority
houfek.cz. 900 SOA ns1.houfek.cz. dnsadmin.houfek.cz. 121 900 600 86400 3600
Additional
. 0 OPT ; payload 4000, xrcode 0, version 0, flags 0