Migrating from VMWare Fusion to VirtualBox: networking

Virtualbox logoIn my previous post on migrating Windows 7 to VirtualBox there were a couple things missing on the networking configuration to make VirtualBox work the same way VMWare does by default.

In VMWare you can just connect to the ip of the guest, the host is by default configured with new virtual network adapters that will route the packages to the guest.

In VirtualBox however by default guests are configured with NAT to allow internet access from the guest through the host, but doesn’t allow connecting from the host to the guest directly, only assigning each port in the host that you want redirected to the guest (which is a PITA).

There are two options to achieve the same result that you had in VMWare:

  1. Change the Network Adapter from NAT to Bridged Adapter. The drawback is that it needs to bridge to a specific hardware adapter (ethernet or airport), so it won’t work if you switch connections.
  2. Add a new Host-Only Network Adapter. First, under VirtualBox global preferences – Network, add a Host-Only network. That will create a virtual interface vboxnet0 in your host machine, and you can customize the ip ranges and DHCP server. Then in the VM settings, under Network, enable Adapter 2 attached to Host-Only adapter and choose the virtual adapter, vboxnet0.

I chose option 2 and works as expected, I just need to connect to (the default assigned ip for the first VM) to get to the host.


The Windows 7 guest gets the ip from DHCP but for some reason it does not get the default gateway. Windows won’t let you assign the network to a Home or Work group without a default gateway, and therefore Windows Firewall will block incoming connections. The default gateway needs to be added by hand to the tcp/ip network configuration by hand (ie. and then you can assign the network to Home/Work and the firewall will allow traffic.

Migrating Windows 7 from VMWare Fusion to VirtualBox

Virtualbox logoI recently had to start using Windows to connect to a client’s VPN network. Their VPN solution only works (or is supported) on Windows, plus the need to test a few things on Internet Explorer 😦

Previously I had used Amazon EC2 whenever I needed to use windows, to avoid license costs, 20GB of my drive wasted and the CPU/RAM overhead, but this time there was no way out, didn’t seem cool to store the VPN credentials on a public cloud instance, although it’s probably as safe. So I bought Windows 7 online and downloaded the 3GB iso image and VMWare Fusion for OS X which happens to have a 30-day trial. Got Win 7 working there with no problems, which is not what I can say about the VPN setup.

Then I got good recommendations to try VirtualBox, which is both open source and free as in beer, and was glad to see there are ways to easily move your VMWare images to VirtualBox.

Step by step instructions

To move the Windows 7 image to VirtualBox 4.1 just needed to

  1. Uninstall the VMWare tools and shutdown windows
  2. Copy the disk files from VMWare image to a new folder
    1. In Documents/Virtual Machines right click on the image, Show package contents
    2. Copy all *.vmdk files to a new folder
  3. Create a new VirtualBox machine with the same characteristics
    1. Make sure you choose Windows 7 64 bits if that’s what you used
    2. On Virtual Hard Disk, choose the main vmdk file you copied in previous step (although you’ll need to change the default storage config later)
    3. Customize created VM settings:
      1. General: Windows 7 64 bits
      2. System/Motherboard: set the same amount of base memory as the VMWare one
      3. System/Motherboard: Enable IO APIC
      4. Storage: By default VirtualBox adds it to SATA controller but you have to remove the SATA controller, and use IDE PIIX4 without host I/O cache, attaching vmdk to primary master IDE, leave CD/DVD drive
  4. Boot the VirtualBox VM and follow any prompt to restart Windows to install new devices
  5. On the VirtualBox Devices menu, click on install guest additions


Several things went wrong before I got it working, so just in case you have the same problems

  • Stuck in “Windows is loading files” black screen, rebooting continuously: make sure you have selected 64 bits Windows and enabled IO APIC
  • Blue screen of death: Remove SATA, SCSI and any other non-IDE controllers from Storage, attach vmdk to IDE and make sure PIIX4 is selected
  • Windows needs to be repaired / Cannot repair windows: same as previous one, make sure disk is attached to IDE