Hyper-V Nested Virtualization
Nested Virtualization is one of the features introduced in the newly released Windows / Hyper-V Server 2016. [1]
The nova Hyper-V Driver can enable nested virtualization for an instance if the CPU feature "vmx" is requested via flavor extra_specs "hw:cpu_features".
Regarding Hyper-V nested virtualization, there are a few things to be kept in mind:
* An instance with nested virtualization enabled cannot have dynamic memory, and its memory cannot be live-resized.
* The guest OS has to be Windows / Hyper-V Server 2016.
* Hosts with Device Guard cannot expose virtualization extensions to guests.
* Hosts with Virtualization Based Security cannot expose virtualization extensions to guests.
This feature was first proposed and discussed during the OpenStack Ocata Summit. [2]
[1] https:/
[2] https:/
Blueprint information
- Status:
- Started
- Approver:
- Matt Riedemann
- Priority:
- Low
- Drafter:
- Claudiu Belu
- Direction:
- Approved
- Assignee:
- Claudiu Belu
- Definition:
- Pending Approval
- Series goal:
- None
- Implementation:
- Beta Available
- Milestone target:
- None
- Started by
- Claudiu Belu
- Completed by
Related branches
Related bugs
Sprints
Whiteboard
Gerrit topic: https:/
Addressed by: https:/
WIP: hyper-v: Adds support for VMs with nested virtualization
We discussed this at the contributors meetup during the Ocata summit. It's a feature parity specless blueprint. -- mriedem 20161117
Marking as blocked since the nova change is a WIP that depends on an unreleased os-win library change. Note that the non-client library release freeze for Ocata is January 19th 2017. -- mriedem 20161229
Addressed by: https:/
Adds CPUFeaturesField to ImageMetaProps
I'm deferring this to Pike since we're now past the feature freeze for Ocata. -- mriedem 20170128
Re-approved for Pike. Claudiu is going to pick this up again. -- mriedem 20170413
The changes for this look abandoned and I'm going to make room for other things that are ready for review in the Pike release, so I'm deferring this to Queens. -- mriedem 20170622