The cinder.interface.volume_management_driver Module

Manage/unmanage existing volume driver interface.

class VolumeManagementDriver

Bases: cinder.interface.base.CinderInterface

Interface for drivers that support managing existing volumes.

manage_existing(volume, existing_ref)

Brings an existing backend storage object under Cinder management.

existing_ref is passed straight through from the API request’s manage_existing_ref value, and it is up to the driver how this should be interpreted. It should be sufficient to identify a storage object that the driver should somehow associate with the newly-created cinder volume structure.

There are two ways to do this:

  1. Rename the backend storage object so that it matches the, volume[‘name’] which is how drivers traditionally map between a cinder volume and the associated backend storage object.
  2. Place some metadata on the volume, or somewhere in the backend, that allows other driver requests (e.g. delete, clone, attach, detach…) to locate the backend storage object when required.

If the existing_ref doesn’t make sense, or doesn’t refer to an existing backend storage object, raise a ManageExistingInvalidReference exception.

The volume may have a volume_type, and the driver can inspect that and compare against the properties of the referenced backend storage object. If they are incompatible, raise a ManageExistingVolumeTypeMismatch, specifying a reason for the failure.

Parameters:
  • volume – Cinder volume to manage
  • existing_ref – Dictionary with keys ‘source-id’, ‘source-name’ with driver-specific values to identify a backend storage object.
Raises:
manage_existing_get_size(volume, existing_ref)

Return size of volume to be managed by manage_existing.

When calculating the size, round up to the next GB.

Parameters:
  • volume – Cinder volume to manage
  • existing_ref – Dictionary with keys ‘source-id’, ‘source-name’ with driver-specific values to identify a backend storage object.
Raises:

ManageExistingInvalidReference – If the existing_ref doesn’t make sense, or doesn’t refer to an existing backend storage object.
unmanage(volume)

Removes the specified volume from Cinder management.

Does not delete the underlying backend storage object.

For most drivers, this will not need to do anything. However, some drivers might use this call as an opportunity to clean up any Cinder-specific configuration that they have associated with the backend storage object.

Parameters:volume – Cinder volume to unmanage