We recently moved to EC2 and started using amazon's elb for load balancing. We're using CloudFlare for DNS which allows us to use a cname the domain root. However, we occasionally have people tell us that our emails are bouncing with some variation of the following error:
firstname.lastname@example.org... Deferred: Connection refused by our-production-loadbalancer.elb.amazonaws.com.
We are using google apps for mail and our MX records are configured properly, so I'm not sure at what point the mail clients or servers are attempting to resolve our domain and receiving the cname record instead.
Does anyone understand why the MX records would be ignored? Is this a result of using a CNAME? I would imagine that the same thing could/would happen if we pointed an A record at an IP address that was also not accepting mail.