2.18.27.143
a2-18-27-143.deploy.static.akamaitechnologies.com
2.18.27.154
a2-18-27-154.deploy.static.akamaitechnologies.com

2a02:26f0:fd00:1a::216:f9cf
2a02:26f0:fd00:1a::216:f9d0

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