Microsoft Adds Nested Virtualization to Select Azure Virtual Machines

Article Written by David Marshall

Interesting news out of Redmond — Microsoft users will now be able to enable nested virtualization (or the ability to run a virtual machine within another virtual machine) in Azure, as this is now a valid deployment option under Microsoft’s new Dv3 and Ev3 series Azure virtual machines (VMs).

The Dv3 and Ev3 series VMs use Hyper-Threading technology found in Intel’s Haswell and Broadwell chip architectures, packing more of a punch in the underlying hardware and allowing it to support larger VM sizes.  The new Dv3 VM sizes are a good balance of memory to vCPU performance, with up to 64 vCPU’s and 256GiB of RAM.  And the newly named Ev3 sizes provide users with more memory to vCPU than the Dv3, so that larger workloads can be run on sizes up to the largest E64 size, with 64 vCPUs and 432GiB of RAM.  And it is that extra power that helps provide for nested virtualization.

By unlocking more power from the underlying hardware, Microsoft has been able to harness better performance and efficiency, resulting in cost savings.  These new Hyper-Threaded sizes are said to be priced up to 28% lower than the previous Dv2 sizes.

What’s the reason for running nested virtualization?

According to Microsoft senior manager Joy Fan, "It can provide great flexibility in supporting your needs in various areas such as development, testing, customer training, demo, etc."

As an example, if you have a testing team using Hyper-V hosts on-premises today, they can now more easily move their workloads to Azure by using nested VMs as virtualized test machines, explained Fan. 

Similarly, developers can use nested VMs to run test code on a current VM that already supports multiple users without affecting their application experience.  You can use the nested virtualization technology to spin up independent environments on demand.  And within nested VMs, even if you are running a chaos environment, your users will not be impacted.

The company said that it plans to continue to expand support to more virtual machine sizes in the coming months.

Availability is limited to a few regions, but this is expected to grow over time.  For now, the new Dv3 instances are offered in Azure’s West US 2, East US 2, West Europe and Southeast Asia Pacific.

For further education, Microsoft provided a diagram on how nested virtualization works.