ns5.cert.at has no MX records.
Question and response
Question
dig ns5.cert.at. MX
Answer
The response has no answer records.
Authority
cert.at. 30 SOA sec1.rcode0.net. lir-tech.nic.at. 2026023329 10800 3600 604800 30
Additional
. 0 OPT ; payload 1400, xrcode 0, version 0, flags 0