mx.postal.etrn.email has no CNAME records.
Question and response
Question
dig mx.postal.etrn.email. NS
Answer
The response has no answer records.
Authority
etrn.email. 3600 SOA ns1.fmt.etrn.com. hostmaster.etrn.com. 2025030901 3600 900 1209600 900
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0