18.210.94.243
ec2-18-210-94-243.compute-1.amazonaws.com
52.203.162.41
ec2-52-203-162-41.compute-1.amazonaws.com

2406:da00:ff00::12d2:5ef3
2406:da00:ff00::34cb:a229

in1-smtp.messagingengine.com.
in2-smtp.messagingengine.com.