VyOS – Open source router and firewall platform
https://vyos.ioVyOS is my go-to router distribution. I use it at client sites, at home, and would not hesitate to recommend it for most router/firewall needs. It runs superbly well on small low powered hardware as well as larger servers. I have never used or needed the paid support, but for a mission critical installation I would think it would be beneficial.
Chapter 6. Virtual Networking - Oracle VM VirtualBox
www.virtualbox.org/manual/ch06.htmlHost-only networking is particularly useful for preconfigured virtual appliances, where multiple virtual machines are shipped together and designed to cooperate. For example, one virtual machine may contain a web server and a second one a database, and since they are intended to talk to each other, the appliance can instruct Oracle VM VirtualBox to set up a host-only …