mx.etrn.com has no MX records.
Question and response
Question
dig mx.etrn.com. MX
Answer
The response has no answer records.
Authority
mx.etrn.com. 3600 SOA ns1.fmt.etrn.com. hostmaster.etrn.com. 2023072471 1800 900 1814400 900
Additional
The response has no additional records.