[New feature] Support for inter-VM LAN

[frisso]

Currently, VMs work in isolation. There are cases in which different VMs should be allocated on the same LAN, sharing the same broadcast domain.
This feature request suggests to introduce the support for services that require multiple VMs running at the same time, possibly with a given network setup.

[palexster]

Hi @frisso ! Currently, VMs of the same user are not isolated and can communicate. We recently installed a Kubernetes cluster of three VMs and it works fine. The isolation is enforced across VMs of different user for security reasons.
The main limitation is represented by the limited CIDRs that do not overlap the one used by the underlying Kubernetes (podCIDR, serviceCIDR). This is due to the fact that Kubernetes does not offer network virtualization facilities, differently from OpenStack.