I have a group of CentOS 7.2 servers running as VMs under VMware's ESXi 6.0. These all reside on the same subnet and we have no problem communicating between the different virtual servers. In addition, each of these servers run a number of libvirt-based LXC containers, also based on CentOS 7.2. The hosts can communicate with their containers without issues and the containers on a given server can communicate with each other. However, containers hosted on two different servers cannot communicate with each other or with other servers. If we duplicate this setup using KVM based VMs instead of ESXi VMs everything works fine--there is no problem communicating between LXC containers regardless of which VM hosts them. I assume this is not a libvirt issue but if anyone has encountered this issue in running libvirt containers under a VMware environment and has found a solution, I'd appreciate hearing from you. Thanks very much, Peter