virtualbox.org

I have one Windows based host and several VM's. Lately I have found most consumer Firewalls to have become bloated, inefficient and short on features or unreliable. Additionally it is not really effective to have one Firewall for the host and one for each running VM. I have quite limited resources.

I would like to find a way to redirect all network traffic for all active VM's and most importantly THE HOST through a separate special VM with a Linux based Firewall installed. This Firewall should be able to manage traffic, not just for the subnet but for individual hosts as well.

If necessary I imagine this can be achieved by the alteration of Routing Rules such that the hosts traffic first travels to the Linux Firewall VM, then back and out onto the LAN/WAN, or at worst the installation of a second network adapter on the host, though I would prefer not to if possible.

I realize this may be difficult or it may not be possible but I would like to try. I have to find someway to reduce the CPU/Memory overheads that this software is imposing.

Hope you can help.

That isn't really a VirtualBox question: it's all about network configuration. So, do it the same way you would if you had a small private LAN and was using one physical PC as a gateway/firewall.

Everything is network related in this topic, and not in scope of Virtualbox, except for how you should configure the host if you also want it to use the guest for networking.
To do so, you need to add a host-only adapter on the host, and then add a virtual NIC on the guest with which you use the host-only interface just created.

The router VM will need to have also a bridged interface for the "outside" world as you'll need to disable TCP/IP on the host for the physical card.