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PowerVM Nova Driver

Include the URL of your launchpad blueprint:

The IBM PowerVM hypervisor provides virtualization on POWER hardware. PowerVM admins can see benefits in their environments by making use of OpenStack. This driver (along with a Neutron ML2 compatible agent and Ceilometer agent) will provide capability for admins of PowerVM to use OpenStack natively.

Problem Description

As ecosystems continue to evolve around the POWER platform, a single OpenStack driver does not meet all of the needs for the varying hypervisors. The work done here is to build a PowerVM driver within the broader community. This will sit alongside the existing libvirt based driver utilized by PowerKVM environments.

This new driver must meet the following:

  • Built within the community
  • Fits the OpenStack model
  • Utilizes automated functional and unit tests
  • Enables use of PowerVM systems through the OpenStack APIs
  • Allows attachment of volumes from Cinder over supported protocols

The use cases should be the following:

  • As a deployer, all of the standard lifecycle operations (start, stop, reboot, migrate, destroy, etc...) should be supported on a PowerVM based instance.
  • As a deployer, I should be able to capture an instance to an image.

Proposed Change

The changes proposed are the following:

  • Create a PowerVM based driver in a StackForge project. This will implement the nova/virt/driver Compute Driver.
  • Provide deployments that work with the OpenStack model.
  • Driver will be implemented using a new version of the PowerVM REST API.
  • Ephemeral disks will be supported either with Virtual I/O Server (VIOS) hosted local disks or via Shared Storage Pools (a PowerVM cluster file system).
  • Volume support will be via Cinder through supported protocols for the Hypervisor.
  • Network integration will be supported via a ML2 compatible Neutron Agent.
  • Automated Functional Testing will be provided to validate changes from the broader OpenStack community against the PowerVM driver.
  • Thorough unit testing will be provided for the driver.

The changes proposed will bring support for the PowerVM hypervisor into the OpenStack ecosystem, following the OpenStack development model.

This development will be done in StackForge in a project named nova-powervm. The intent is that the completion of this work will provide the foundation to bring the PowerVM Nova driver (with supporting components) into Nova Core via a separate BluePrint in a future release of OpenStack.

Until a subsequent BluePrint is proposed and accepted, this driver is to be considered experimental.

Data Model Impact

No data model impacts are anticipated as part of this work.


The intent of this work item is to enable PowerVM to fit within the broader OpenStack ecosystem, without requiring changes to the REST API.

As such, no REST API impacts are anticipated.

Security Impact

The user may need to configure the credentials to communicate with the PowerVM REST API via a CONF file. These should be encoded.

New root wrap policies may need to be updated to support various commands for the PowerVM REST API.

No other security impacts are foreseen.

Notifications Impact

No new notifications are anticipated.

Other End User Impact

The administrator will notice new logging messages in the nova compute logs.

Performance Impact

It is a goal of the driver to deploy systems with similar speed and agility as the libvirt driver within OpenStack.

Since this process should match the OpenStack model, it is not planned to add any new periodic tasks, database queries or other items.

Performance impacts should be limited to the Compute Driver, as the changes should be consolidated within the driver on the endpoint. The API processes for instance should not be impacted.

Other Deployer Impact

The cloud administrator will need to refer to documentation on how to configure OpenStack for use with a PowerVM hypervisor.

The existing configuration file attributes will be reused as much as possible. This reduces the number of PowerVM specific items that will be needed. However, the driver will require some PowerVM specific options.

In this case, we plan to keep the PowerVM specifics contained within the configuration file (and driver code). These will be documented on the driver's wiki page.

There should be no impact to customers upgrading their cloud stack as this is a genesis driver and should not have database impacts.

Developer Impact

The code for this driver will be contained within a powervm StackForge project. The driver will be contained within /nova/virt/powervm/. The driver will extend nova.virt.driver.ComputeDriver.

The code will interact with PowerVM through the pypowervm library. This python binding is a wrapper to the PowerVM REST API. All hypervisor operations will interact with the PowerVM REST API via this binding. The driver will be maintained to support future revisions of the PowerVM REST API as needed.

For ephemeral disk support, either a Virtual I/O Server hosted local disk or a Shared Storage Pool (a PowerVM clustered file system) will be supported. For volume attachments, the driver will support Cinder based attachments via protocols supported by the hypervisor.

For networking, a blueprint is being proposed for the Neutron project that will provide a Neutron ML2 Agent. This project will be developed in StackForge alongside nova-powervm. The Agent will provide the necessary configuration on the Virtual I/O Server. The Nova driver code will have a /nova/virt/powervm/ file that will configure the network adapter on the client VM.

Automated functional testing will be provided through a third party continuous integration system. It will monitor for incoming Nova change sets, run a set of functional tests (lifecycle operations) against the incoming change, and provide a non-gating vote (+1 or -1).

Developers should not be impacted by these changes unless they wish to try the driver.

Until a subsequent blueprint is proposed and accepted, unless otherwise noted, the driver will be considered experimental.

Community Impact

The intent of this blueprint is to bring another driver to OpenStack that aligns with the ideals and vision of the community.

It will be discussed in the Nova IRC and mailing lists.


No alternatives appear viable to bring PowerVM support into the OpenStack community.



Primary assignee:


Other contributors:

thorst dwarcher efried

Work Items

  • Create a base PowerVM driver that is non-functional, but defines the methods that need to be implemented.
  • Implement the host statistics methods (get_host_stats, get_host_ip_addr, get_host_cpu_stats, get_host_uptime, etc.).
  • Implement the spawn method.
  • Implement the destroy method.
  • Implement the instance information methods (list_instances, instance_exists, poll_rebooting_instances, etc.).
  • Implement the live migration methods. Note that, for ephemeral disks, this will be specific to Shared Storage Pool environments where the Virtual I/O Servers on the source and target systems share the same (clustered) file system.
  • Implement support for Cinder volume operations.
  • Implement an option to configure an internal management NIC - used for Resource Monitoring and Control (RMC) as part of deploy. This is a prerequisite for migration and resize. This will be controlled as part of the CONF file.
  • Implement the network interface methods (attach_interface and detach_interface). Delegate the Virtual I/O Server work to the corresponding Neutron ML2 agent.
  • Implement an automated functional test server that listens for incoming commits from the community and provides a non-gating vote (+1 or -1) on the change.


  • Will utilize the PowerVM REST API specification for management. Will utilize future versions of this specification as it becomes available:
  • Will build on top of the pypowervm library. This will be a prerequisite to utilizing the driver and identified in the requirements.txt file.


Tempest Tests

Since the tempest tests should be implementation agnostic, the existing tempest tests should be able to run against the PowerVM driver without issue. This blueprint does not foresee any changes based off this driver.

Thorough unit tests will be created within the Nova project to validate specific functions within this driver implementation.

Functional Tests

A third party functional test environment will be created. It will monitor for incoming nova change sets. Once it detects a new change set, it will execute the existing lifecycle API tests. A non-gating vote (+1 or -1) will be provided with information provided (logs) based on the result.

API Tests

The REST APIs are not planned to change as part of this. Existing APIs should be valid. All testing is planned within the functional testing system and via unit tests.

Documentation Impact

User Documentation

Documentation will be contributed which identifies how to configure the driver. This will include configuring the dependencies specified above.

Documentation will be done on wiki, specifically at a minimum to the following page:

Interlock is planned to be done with the OpenStack documentation team.

Developer Documentation

No developer documentation additions are anticipated. If the existing developer documentation is updated to reflect more hypervisor specific items, this driver will follow suit.