Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Couldn't find any help @ google or here.

The scenario: Windows Server 2008 Std x64 on i7-975, 12 GB RAM. The server is running in a data centre. One hardware NIC - RealTek PCIe GBE -> one MAC Address. The data centre provides us 4 static external IP's. The first is assigned to the host by default of course. I have ordered all 4 IP's, the data centre can assign the available IP's to the physical MAC address of the given NIC only. This means one NIC, one MAC Address, 4 IP's. Everything works fine so far.

Now, what I would like to have: Installed VirtualBox with 1-3 guests running, each gets it's own external IP assigned. Each of it should be an standalone Win Server 2008. It looks like the easiest way would be to put the guests into an virtual subnet and routing all data coming to the 2nd till 4th external IP through to this guests using there subnet IP's.

I have been through the VirtualBox User Manuel regarding networking.

What's not working: I can't use bridged networking without anything else, because the IP's are assigned to the one MAC address only. I can't use NAT networking because it does not allow access from outside or the host to the guest. I do not wanna use port forwarding. Host-only networking itself would not allow internet access, by sharing the default internet connection of the host, internet is granted from the guest to the outside but not from outside or the host to the guest. InternalNetworking is not really an option here.

What I have tried is to create an additional MS Loopback adapter for a routed subnet, where the Vbox guests are in, now the idea was to NAT the internet connection to the loopback 'subnet'. But I can't ping the gateway from the guests.

By using route command in the command shell or RRAS (static route, NAT) I didn't get there as well.

Solutions like the following do work for the one way, but not for the way back:

For your situation, it might be best to use the Host-Only adapter for ICS. Go to the preferences of VB itself and select network. There you can change the configuration for the interface. Set the IP address to, netmask Disable the DHCP server if it isn't already and that's it. Now the Guest should get an IP from Windows itself and be able to get onto the internet, while you can also access the Host.

Slowly I'm pretty stucked with this topic. There is a possibility I've just overlooked something or just didn't getting it by trying, especially using RRAS, but it's kinda hard to find useful howto's or something in the web.

Thanks in advance!

Best regards, Simon

share|improve this question

closed as too localized by Michael Hampton, mdpc, Khaled, Ward, Scott Pack Feb 4 '13 at 16:05

This question is unlikely to help any future visitors; it is only relevant to a small geographic area, a specific moment in time, or an extraordinarily narrow situation that is not generally applicable to the worldwide audience of the internet. For help making this question more broadly applicable, visit the help center.If this question can be reworded to fit the rules in the help center, please edit the question.

The Virtual NIC will have a MAC address even when in bridged mode. Any chance you could get the IP Address assigned the virtual MAC and things would "just work" in bridged mode? – Goyuix Jul 29 '10 at 14:11

I recently had the same issues assigning IP addresses to virtualbox servers on a Windows Server 2008 host and while it may not help you at this point it might help some one else...

Assign the virtual IP addresses to the external NIC on the host machine. On the virtualbox networks settings make a host only network with the guest IP address and disable DHCP which is turned on by default. On the guest window select device->network adapters and set up a bridged adapter set the name drop down to your physical NIC. On the guest OS set the guest IP subnet mask and gateway to the desired IP address.

share|improve this answer

Not the answer you're looking for? Browse other questions tagged or ask your own question.