dns-master.metrocast.net has no MX records.
Question and response
Question
dig dns-master.metrocast.net. MX
Answer
The response has no answer records.
Authority
metrocast.net. 3600 SOA dns-master.metrocast.net. root.dns-master.metrocast.net. 2026022701 1800 900 3600000 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0