We do have an internal network setup for all our vm's by default. Nevertheless it is not activated. For us to activate a private network inside your vps please contact support and it can only be done (for now) if you have a server on the same node.
This can have huge advantages like an extremely fast transfer speed between the servers of up to 1Gbps or around 125MB/s. You will be able to make full usage of our NVMe drives.
