mta1.datacenter.fi has no CNAME records.
Question and response
Question
dig mta1.datacenter.fi. NS
Answer
The response has no answer records.
Authority
datacenter.fi. 4611 SOA ns1.datacenter.fi. hostmaster.datacenter.fi. 2026020301 86400 7200 3600000 172800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0