13.224.205.14
server-13-224-205-14.phl50.r.cloudfront.net
13.224.205.24
server-13-224-205-24.phl50.r.cloudfront.net
13.224.205.64
server-13-224-205-64.phl50.r.cloudfront.net
13.224.205.99
server-13-224-205-99.phl50.r.cloudfront.net

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