ns1.rackmy.com has no MX records.
Question and response
Question
dig ns1.rackmy.com. MX
Answer
The response has no answer records.
Authority
rackmy.com. 300 SOA ns1.ral.hostedsolutions.com. hostmaster.hostedsolutions.com. 2016022213 900 600 86400 300
Additional
. 0 OPT ; payload 1220, xrcode 0, version 0, flags 0