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I'm playing around with Hyper-V on a Windows Server 2012 machine. It has 3 NIC's. #0 is dedicated to the host, #1 is on a virtual switch with all VM's on it.

I want NIC #2 to be dedicated to a particular VM, e.g. the host shouldn't bother with it and it should only have 1 MAC and IP for the client VM. (as if the VM was a physical machine with that particular NIC)

The only way to do this I see now is to create a "external" virtual network and place only that VM on the network. This of course has advantages but also leaves me to deal with 2 IP's and 2 MAC's: one for the host and one for the VM.

Is this possible and if so how (and is it recommended?)

share|improve this question
Not 100%, since it wouldn't be strange if network devices are treated differently in a hypervisor, also that question is from 2010 and there have been 2 new versions of HyperV in the meantime. – dtech Dec 30 '12 at 10:19
Unfortunately they didn't add PCI passthrough in 2012 either. Sorry. – Michael Hampton Dec 30 '12 at 14:40
So the only solution is to create a virtual switch for NIC #2 and connect only the specific VM to it? – dtech Dec 30 '12 at 16:19
That's about the only thing I can come up with. – Michael Hampton Dec 30 '12 at 16:27
up vote 2 down vote accepted

Creating an external network won't create two MAC addresses and two IP addresses unless you also choose "Allow management operating system to share this network adapter." If you leave that box unchecked (or the equivalent operations in PowerShell) then the management OS won't bind anything to it except the switch. If you enable VMQ or SR-IOV on it, then you'll even have dedicated hardware routing the traffic into the VM.

share|improve this answer
Technically there'll still be 2 MAC's, but the host wont request an IP, thanks! – dtech Jan 4 '13 at 10:03
Yes, there will technically be 2 MACs. But the default MAC in the NIC won't be used for anything. – Jake Oshins Jan 4 '13 at 20:46

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