cAA51584D.static.as2116.net has no MX records.
Question and response
Question
dig cAA51584D.static.as2116.net. MX
Answer
The response has no answer records.
Authority
static.as2116.net. 600 SOA dns1.as2116.net. hostmaster.as2116.net. 2019010701 28800 3600 2419200 600
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0