host4.cityonlinebd.net has no MX records.
Question and response
Question
dig host4.cityonlinebd.net. MX
Answer
The response has no answer records.
Authority
cityonlinebd.net. 604800 SOA ns1.cityonlinebd.net. nabin.cityonlinebd.net. 2026021616 604800 86400 2419200 604800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0