smtp-bulk.osanet.cz has no NS records.
NS records for this zone are defined at osanet.cz.
NS records for this zone are defined at osanet.cz.
Question and response
Question
dig smtp-bulk.osanet.cz. NS
Answer
The response has no answer records.
Authority
osanet.cz. 86400 SOA decsys.vsb.cz. hostmaster.vsb.cz. 2025032500 28800 7200 604800 86400
Additional
. 0 OPT ; payload 1472, xrcode 0, version 0, flags 0