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I have a Windows 2008 R2 Standard host system with the Hyper-V VM hosted (Win 2008 R2 too). Host system has public IP ( for example) bounded to Hyper-V external virtual network, which is connected to physical network controller. Also I have failover subnet Some IPs from this subnet are bound to virtual network controller and works fine. But when I bound some other IPs to VM's NIC - it is not visible nor from outside and hasn't access to Internet. But it is visible from host and can ping host too. Is there any way to bound some other IPs to VM's NIC, so it can be accessible outside? Thanks a lot.

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It may be clearer if you could provide some kind of network diagram for us. – Dan Dec 22 '11 at 11:02
Not sure, that I understand, what kind of diagram can I write for one shared NIC by host and VM. Can you advise me a tool for such kind of diagram? – Stan Dec 22 '11 at 14:23
up vote 1 down vote accepted

I don't think anyone has been answered you yet because it is difficult to truly grasp the meaning of your question.

That said, the best practice on Hyper-V is to reserve one NIC as a "Management Adapter." This NIC will be configured just like any other regular NIC on any other physical host on your network, and you do not use it as a Hyper-V adapter that your VMs or HyperV Virtual Switch will use.

Then use another separate adapter to dedicate to the HyperV Virtual Switch. I would recommend not setting DNS servers or a default gateway on this NIC. This NIC simply needs to provide physical network access to your VMs. Creating an external Virtual Switch is what you want to do if you want your VMs to be able to communicate with the rest of the world.

Then connect your VMs to that virtual switch, give them a full IP stack as if they were regular physical hosts on your network, and go!

If you want those VMs to host services, you will then need to configure your NAT'ing router to forward ports to those internal VMs.

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Thank you. This was the closest answer to the solution I have implemented. Internal virtual network + NAT did the trick. – Stan Dec 23 '11 at 21:19

(presuming I understand this right a viso diagram would be helpful) If it's an External vswitch than the host should not have access to the VM (unless the machines are on the same subnet so they could communicate via the physical adapter)

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