3.136.140.67
ec2-3-136-140-67.us-east-2.compute.amazonaws.com
3.138.51.11
ec2-3-138-51-11.us-east-2.compute.amazonaws.com
3.140.123.38
ec2-3-140-123-38.us-east-2.compute.amazonaws.com

alt1.aspmx.l.google.com.
alt2.aspmx.l.google.com.
alt3.aspmx.l.google.com.east-1.amazonaws.com.
alt4.aspmx.l.google.com.
aspmx.l.google.com.
inbound-smtp.us-east-1.amazonaws.com.
mxa.mailgun.org.