91.65-93.249.11.217.in-addr.arpa has no NS records.
NS records for this zone are defined at 65-93.249.11.217.in-addr.arpa.
NS records for this zone are defined at 65-93.249.11.217.in-addr.arpa.
Question and response
Question
dig 91.65-93.249.11.217.in-addr.arpa. NS
Answer
The response has no answer records.
Authority
65-93.249.11.217.in-addr.arpa. 2560 SOA ns.cybersales.cz. hostmaster.cybersales.cz. 1774656582 16384 1800 1048576 2560
Additional
The response has no additional records.