_spf.datacenter.fi has no NS records.
NS records for this zone are defined at datacenter.fi.
NS records for this zone are defined at datacenter.fi.
Question and response
Question
dig _spf.datacenter.fi. NS
Answer
The response has no answer records.
Authority
datacenter.fi. 4592 SOA ns1.datacenter.fi. hostmaster.datacenter.fi. 2026020301 86400 7200 3600000 172800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0