[libvirt-users] Networking issues with lxc containers in AWS EC2

I've created an EC2 AMI for AWS that essentially represents a CentOS 7 "hypervisor" image. I deploy instances of these in AWS and create an number of libvirt based lxc containers on each of these instances. The containers run fine within a single host and have no problem communicating with themselves as well as with their host, and vice versa. However, containers hosted in one EC2 instance cannot communicate with containers hosted in another EC2 instance. We've tried various tweaks with our Amazon VPC but have been unable to find a way to solve this networking issue. If I use something like VMware or KVM and create VMs using this same hypervisor image, the containers running under these VMs can communicate with with each other, even across different hosts. My real question is has anyone tried deploying EC2 images that host containers and have figured out how to successfully communicate between containers on different hosts? Peter