34.254.114.23
ec2-34-254-114-23.eu-west-1.compute.amazonaws.com
52.48.50.242
ec2-52-48-50-242.eu-west-1.compute.amazonaws.com
99.80.157.25
ec2-99-80-157-25.eu-west-1.compute.amazonaws.com

eu-smtp-inbound-1.mimecast.com.
eu-smtp-inbound-2.mimecast.com.