Microsoft Announces SMB 2.2 and NAS Support for Hyper-V 3.0 in Windows 8


Big news this morning from the Storage Developer’s Conference (SDC) at the SNIA Cloud Plugfest in Santa Clara, California. Microsoft announced the availability of the SMB 2.2 protocol (formerly known as CIFS). Details include a number of new functional specifications along with support for running Hyper-V 3.0 and applications over the updated NAS protocol with the release of both in Windows 8.



Over the past 5 years I’ve advocated for the adoption of NAS storage protocols within virtual infrastructures and cloud computing initiatives as they provide significantly greater functional capabilities and operational ease than what is currently possible with SAN access. Suffice to say I’m somewhat excited with Microsoft’s announcement and would like to share a few thoughts and details.

I’ve written extensively on the specific details around the benefits of deploying a virtual infrastructure on NAS, so if you’re interested in understanding more of the details, please see some of the articles located here.


Joining Microsoft for the announcement was Dennis Chapman, Technical Director at NetApp, who stated a key to the selection of NetApp as the leading development partner for SMB 2.2 was our market leadership in advancing NAS capabilities with some of the world’s most demanding, mission-critical applications. The list of application spanned web services to high performance computing, and specifically cited high performance Oracle databases and cloud computing initiatives on VMware.

The Enhancements in SMB 2.2 are Ideal for Hyper-V

The development efforts around SMB 2.2 are targeting improvements in areas such as performance, scalability, resiliency, and manageability. Below are just a few areas of focus shared today that I believe will significantly enhance the capabilities of a NAS-based Hyper-V virtual infrastructure…

  • Remote VSS – With Volume Shadow Copy Service (VSS) customers will receive the same type of application consistent snapshot based backups as we’ve provided for years with deployments on FC, FCoE, and iSCSI.
  • Cluster Client Failover – This mechanism enables VMs to reattach to their handles based upon an “instance ID.” The goal is to provide VMs with a means to transparently and non-disruptively move between multiple storage access points.
  • Unified SAN/SMB Copy Offload – This one is pretty cool. SMB2.2 will provide copy offload capabilities based on the T10 approved mechanism like many are familiar with in vSphere. With SMB 2.2 copy offload will extend to provide unified offload support for LUNs and files.
  • Multi-Channel (MPIO) – Provides the ability to access multiple Ethernet links as a logical pool supporting multiple SMB sessions and providing native bandwidth aggregation, link failover, MPIO intelligence. This is enhancement provides capabilities analogous to those currently available in NFSv4.
  • Continuous Availability – Client/server mediated recovery from network and server failure with application transparency. Like Multi-Channel IO, this feature is somewhat analogous to capabilities available in NFSv4.

This list of enhancements and new capabilities is by no means a definitive list of what’s being developed. Consider it my abbreviated list around the technologies I believe will be most relevant for Hyper-V deployments in the near future. I’m sure there are others at Microsoft and NetApp, and throughout the storage industry who will provide additional coverage around the additional capabilities in SMB 2.2 such as the Witness Protocol, BranchCachev2, SMB Direct, etc.


Microsoft logo
Wrapping Up This Post

Through our collaborative engineering efforts work Microsoft; customers deploying Hyper-V on NetApp via SMB 2.2 will soon gain the high performance, scalability, and management simplicity of NAS, along with unparalleled application level integrations in areas such as application aware backups and availability.

The shift to file based storage platforms is well underway and the evidence is abundant; ranging from independent, multi-year industry reports, to enhanced support for NFS in a number of virtualized applications and platforms such as Zimbra (support), XenDesktop (recommended), vSphere 5 VSA (only protocol), etc. Once one understands that NAS is every bit as capable as SAN is in providing high performance and low latency access to virtualized data sets, then one can be free to consider the benefits of storage as a shared, networked service.

If you think NAS access is a radical change, you may need to brace yourself as there’s much more innovation on the storage horizon. I view NAS access by the hypervisors as one that is orders of magnitude close to an Object-oriented storage model than a SAN, and this looks to be the next ‘big deal’ in terms of storage connectivity and access.
If you’re not on NAS today, maybe you should being looking at it for your virtual infrastructure.

SMB 2.2 is targeted to be released with Microsoft Windows Server 8 and will be supported in Data Ontap 8.2, both are scheduled for release sometime in 2012. Stay tuned, I’ll share more as we inch closer to the release dates.


  1. So, what about for Exchange? Yes, if you have an Exchange VM provisioned on NFS – it works, but isn’t currently supported…

    As per

    ‘All storage used by an Exchange guest machine for storage of Exchange data must be block-level storage because Exchange 2010 doesn’t support the use of network attached storage (NAS) volumes. Also, NAS storage that’s presented to the guest as block-level storage via the hypervisor isn’t supported.’

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