ns2.dc-frankfurt.com has no NS records.
NS records for this zone are defined at dc-frankfurt.com.
NS records for this zone are defined at dc-frankfurt.com.
Question and response
Question
dig ns2.dc-frankfurt.com. NS
Answer
The response has no answer records.
Authority
dc-frankfurt.com. 86400 SOA ns1.dc-frankfurt.com. hostmaster.dc-frankfurt.com. 2025091216 3600 600 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0