Private networks on multiple hosts with SCVMM 2012 SP1

Based on the blog post by Damian Flynn and Nigel Cain I tried the following:

  1. Created the logical network "Lab" with "Allow new VM Networks created on this logical network to use virtualization" and the network site "Lab_0" and subnet
  2. Created an IP Pool for the Logical Network (I thought IP Pools were optional?)
  3. Created the VM Network Lab 00 with Isolation, VM Subnet and no gateway.
  4. Tried to associate the NIC of a VM with the newly created switch.

After this, I get an error saying "VMM Could not find any virtual switch on host that can connect to the VM Network"

So then I tried creating a virtual switch, called LABSWITCH, try to associate the virtual switch with the host, get a warning that "VMM Cannot use LABSWITCH to create a virtual switch as there are no uplink port profile sets present on this logical switch".

Onwards we go, and I created a native port profile, associated it with LABSWITCH, try adding the virtual switch with the host. It works, and I try to connect the VM to the network, but now Lab 00 is gone. 

Now I'm lost. Am I even on the right track?

August 2nd, 2013 10:11am

Since this must be 2012 not 2012 R2, did you enable the network virtualization filter driver on each physical NIC that has an Extenral Virtual Switch?

(SCVMM does not do this for you).  (through Hyper-V)

or  (through SCVMM)

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August 2nd, 2013 11:14am

In my lab/test/development environment I would like to have several "private" networks with connectivity between hosts. After looking around this seems to be possible by using isolated VM Networks and NVGRE for tunneling traffic between hosts. I've been trying to set this up using SCVMM 2012 SP1, but I can't seem to get the isolated VM network to work. 

Is it actually possible to create VM networks that are isolated which functions like a private network with SCVMM 2012 SP1? Would it then also be possible to create the tunnel between the hosts? From what I can find in the forums, it wasn't possible before, but it seems possible with SP1.

August 2nd, 2013 4:01pm

SCVMM 2012 SP1 plus Hyper-V 2012.

Creating the Isolated VM Networks is actually rather straightforward, but not intuitive to setup.

It is when you want a gateway (allow the VM network traffic to exit the Virtual Network through a router or RRAS device) that the SCVMM 2012 SP1 story is not entirely complete.

Damian Flynn and Nigel Cain did a whole blog series on the networking:

And Kristian Nese did some writing on it as well:

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August 2nd, 2013 4:51pm

It seems I had to enable WNV for each NIC using Powershell instead of using the server UI to actually enable it. Pretty strange behavior, but after doing this on the hosts I at least got the network virtualization working.

Before I close this question, I just have another thing I'm curious about. As this is and will be a lab environment, and I'd like to create networks being as real life as possible, I'd like IP-addresses to be provided by a DHCP server for the internal/isolated networks. According to the documentation I've found (like an isolated network requires IP Pools for the Logical and VM network. This off course means that hypervisor will provide IP addresses for VMs on the network, and not the DHCP server on the network.

I got this working using a VLAN-based configuration (instead of pure WNV/network isolation), but then I couldn't get NVGRE working. What is the easiest way of accomplishing having isolated networks, IPs provided by a DHCP server running as a VM, and encapsulated traffic between VMs on hosts without having to make changing (like creating a bunch of VLANs) on the (physical) network?

August 6th, 2013 5:13pm

A DHCP server within a virtual network is not yet supported.

scvmm actually has a DHCP responder switch extension to handle VMs within a virtual network that are simply set to DHCP and not static.

But the IP address still come from an IP pool.

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August 6th, 2013 7:26pm

But would NVGRE between hosts be possible in a VLAN-configuration without IP Pools?
August 7th, 2013 2:20am

Then you would be VLAN routing at the physical switch layer.

NVGRE fits the place where you want isolation, but only at the software layer, without applying any configuration to physical switches.

So yes,  using VLANs would give you what you need, but you can't also layer NVGRE on the top - you need one isolation model or the other.

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August 7th, 2013 8:59am

Here more information and how to configure Logical Networks on SCVMM 2012 SP1

September 19th, 2013 9:37am

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