Nat network with Host

[Warren MacEvoy]

The most commonly useful interface for a virtual machine is a nat network which includes a route to the host. This is almost stunningly difficult to do in virtualbox for the following reasons:

1. There is no uniform network interface management. Host-only and Nat-network configurations are managed through two different configuration panels in two different location of the user interface. I highly recommend a user experience test with new users to evaluate your user interface design.
2. The host is not a part of the nat network. Instead virtual machines need two (!) interfaces with proper routing in order to talk to the world and the host.
3. When creating the host-only network, the DHCP server is not configured by default, which means the interface by default has no address.
4. Because there are two network interfaces with two IP addresses, configuring services can be problematic.
5. Because the network is custom, the virtual machine is not portable.

The simplest system has one network interface, and no interesting routing. I have decided to try VirtualBox for teaching unix, operating systems, and networking in our computer science program. The details needed to explain how to use VBox and why things just don't work is a real impediment to my ability to recommend its use. Please please make this initial experience (and long term benefit) better.

[socratis]

1. The interface went a major rework in 5.2.x as you saw. I wouldn't be surprised if things change in the future.
2. The whole idea is that the host is *not* part of a VM. That the VMs are isolated. It's by design.
3. By "configured" I believe you might mean "enabled"?
4. If you want to go manually, yes, you'd better know what you're doing. If you have no idea what a netmask is, you'd better leave the network configuration to its DHCP default that comes standard with every other client.
5. True, the network is not saved with per VM, but per host. What if you were to send me a VM that was conflicting with my network? I don't know what you might setup, you don't know what my LAN looks like. Instead of assuming, and risking a network havoc, play it safe.

[michaln]

The most commonly useful interface for a virtual machine is a nat network which includes a route to the host.

The option most commonly used by VirtualBox users is actually basic NAT, because it's by far the simplest to set up (requires zero initial configuration) and is sufficient for most users' needs. Bridged and host-only are also popular networking options. Actually the fact that what you want to achieve is so difficult to set up should be a pretty strong hint that it's a very exotic configuration

If you know where we can find a large pool of neophyte users whose reaction to NAT network configuration or DHCP setup will be anything other than "huh?", please let us know. That would be quite useful, but it's far from the typical VirtualBox user profile. Not saying your suggestions are bad, just that you're talking about something that from VirtualBox's perspective is a highly unusual usage scenario.