For a virtual machine that simply needs internet access, start with NAT. Choose a different network mode only when you know which devices must communicate. A VM getting online, two VMs seeing each other and another computer reaching a VM are three different requirements.
Choose a mode by the connection you need
| Mode | Main purpose | Key limit |
|---|---|---|
| NAT | Give one VM outbound access through the host | Inbound connections normally need port forwarding. |
| NAT Network | Let selected VMs share a network with outbound access | Create and select the same named NAT network. |
| Bridged Adapter | Put the VM on the host’s physical network | The LAN’s rules, addressing and firewall still apply. |
| Host-only | Communication between the host and selected VMs | No built-in route to the internet. |
| Internal Network | Communication between VMs on the same named internal network | The host is not automatically a member. |
| Not attached | Keep a virtual adapter present without a connection | The guest sees a disconnected link. |
Oracle’s VirtualBox networking documentation explains the available modes. NAT and NAT Network are separate choices. Giving two VMs ordinary NAT does not automatically put them together on one shared virtual LAN.
Set the VM’s adapter
- Shut down the VM normally before changing its network setup.
- In VirtualBox Manager, open its Settings > Network.
- Enable the adapter, select the attachment mode and choose the relevant host interface or named virtual network.
- Keep Cable connected enabled when you want a working link.
- Start the guest and check its network configuration, usually with automatic addressing first.
For host-only or NAT Network setups, create the network in VirtualBox’s Network tool if one does not exist. Menus can differ by host operating system and VirtualBox version.
Understand exposure before choosing Bridged
A bridged guest can behave like another machine on the LAN. That can be useful for a test server, but it also means other devices may reach its listening services. Keep the guest firewall enabled and use a network you are authorized to test on. Wi-Fi and managed networks can impose additional restrictions.
Troubleshoot one layer at a time
Check that the host itself is online, the virtual cable is connected, and the guest has a sensible address and DNS configuration. A guest firewall can block a service even when browsing works. Host-only and Internal are not internet modes unless you deliberately add routing elsewhere.
If you also use another hypervisor, our VMware network-mode guide explains the comparable ideas. Matching a mode name is less useful than matching the intended path between the guest, host and outside network.
Frequently asked questions
Which mode should I try for ordinary internet access?
NAT is usually the simplest starting point for a single guest.
Are NAT and NAT Network identical?
No. NAT Network can put selected VMs on a shared named network; ordinary per-VM NAT does not do that automatically.
Does host-only networking include internet access?
Not by itself. It connects the host and selected guests without a built-in route to external networks.
Does Bridged bypass the guest firewall?
No. Guest firewall rules, service settings and the physical network's policies still apply.