UPDATE: New Test Lab Guide Released: Deploying Windows Server 2012 R2 Network Virtualization with System Center 2012 R2 Virtual Machine Manager.

Network Virtualization, and Software-Defined Networking (SDN) at-large, have been getting a lot of attention recently.  After reviewing the network traffic patterns in heavily virtualized datacenters, many IT Pros are beginning to realize that a substantial portion of datacenter network traffic is occurring between virtual machines running on the same virtualization host.  In addition, organizations are beginning to evaluate options for defining network-level isolation between virtualized subnets in a manner that provides greater scalability and easier management than a traditional VLAN approach.

Based on this, it makes sense that the networking industry is moving towards bringing layer-3+ networking capabilities directly into the hypervisor.  Essentially, network virtualization allows us to abstract routing and switching from a physical network infrastructure, extending benefits similar to what we’ve realized with server workloads via server virtualization.

At VMworld recently, IT Pros were initially impressed with the new network virtualization capabilities that VMware demonstrated in their early pre-release version of the VMware NSX product, based largely on the VXLAN and STT overlay protocols and code from their previous Nicira acquisition.  But, after walking away from the excitement of a big trade show event and pondering network virtualization as it pertains to their environment in more detail, I’ve also heard some early concerns expressed with VMware NSX, such as:

  • How much does it cost? I’ve already spent quite a bit on vSphere and vCenter, and I’m not sure I have budget for yet another separately licensed virtualization product.
  • Is it compatible with what I have? I’ve invested in 3rd party products that replace VMware’s inbox virtual switch, such as the Cisco Nexus 1000V … it doesn’t appear that I can leverage this investment with VMware NSX.
  • Why can’t I use vCenter to manage VMware NSX? It seems like every new solution in the virtualization space introduces another new management tool. With each change, I’m expected to shift gears and switch to a new tool for provisioning/managing VMs and virtualized resources.

VMware NSX isn’t expected to be available until later this year, so in the meantime, consider evaluating alternatives for network virtualization that are actually shipping today.  In this article, I’ve included a learning roadmap for understanding and evaluating our network virtualization solution, Hyper-V Network Virtualization in Windows Server 2012.

Hyper-V Network Virtualization

No added cost! In fact, it surprises many of these same IT Pros to learn that Microsoft has had network virtualization built-in to Hyper-V since the launch of Windows Server 2012 … at no additional cost.  If you’re primarily virtualizing Windows Server workloads in your datacenter today, chances are that your organization may already own licenses for Windows Server 2012, entitling you to leverage core virtualization features, such as Hyper-V and Hyper-V Network Virtualization.

Hyper-V Network Virtualization aims to solve the same set of problems as VMware NSX – streamline, automate and reduce capital & operational costs of networking by virtualizing and consolidating network intelligence into the core hypervisor platform – but does so by using a different overlay protocol: NVGRE. 

To learn a bit more about NVGRE, see the following article:

And, to learn more about the technical details associated with how Microsoft implements NVGRE in Hyper-V Network Virtualization …

Hyper-V Network Virtualization is just one component of the overall Software-Defined Networking (SDN) solution set present in Windows Server 2012 and Windows Server 2012 R2.  To review the full in-the-box SDN solution, be sure to check out the following excellent article:

Is Hyper-V Network Virtualization Compatible with my Network?

Yes! Based on the well understood GRE protocol, NVGRE can provide an easier path to compatibility with existing network devices, because many layer-3 devices are already GRE-aware and can support NVGRE traffic as an overlay on top of a physical network without modification.  In addition, Microsoft continues to extend Hyper-V Network Virtualization compatibility in new releases of Windows Server.  For instance, in Windows Server 2012 R2, Microsoft has enhanced Hyper-V Network Virtualization so that it can interoperate with other Hyper-V Virtual Switch extensions that you may already be using or planning to use, such as the Cisco Nexus 1000V Switch for Hyper-V.

To learn more about the enhancements to Hyper-V Network Virtualization in Windows Server 2012 R2 …

How do I configure & manage Hyper-V Network Virtualization?

Easy! You can use the same tool for managing Hyper-V Network Virtualization that you’d normally use for managing VMs and Private Clouds: Virtual Machine Manager in System Center 2012 SP1 or R2.  Instead of using separate tools for managing storage, networking, hosts, virtual machines and applications, System Center provides a single tooling for managing your end-to-end datacenter fabric and the Private Clouds that it supports.

To learn the steps involved in configuring Hyper-V Network Virtualization using Virtual Machine Manager, watch the following demo from our Build Your Private Cloud series:

How Are You Planning to Use Network Virtualization?

Have you found an interesting use case in your environment for Hyper-V Network Virtualization?  Be sure to share your story in the comments below!

Additional resources you may also be interested in …