The cinder.interface.volume_snapshotmanagement_driver Module

Manage/unmanage existing volume snapshots driver interface.

class VolumeSnapshotManagementDriver

Bases: cinder.interface.base.CinderInterface

Interface for drivers that support managing existing snapshots.

manage_existing_snapshot(snapshot, 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 snapshot structure.

There are two ways to do this:

  1. Rename the backend storage object so that it matches the snapshot[‘name’] which is how drivers traditionally map between a cinder snapshot and the associated backend storage object.
  2. Place some metadata on the snapshot, or somewhere in the backend, that allows other driver requests (e.g. delete) to locate the backend storage object when required.
Parameters:
  • snapshot – The snapshot 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.
manage_existing_snapshot_get_size(snapshot, existing_ref)

Return size of snapshot to be managed by manage_existing.

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

Parameters:
  • snapshot – The snapshot 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_snapshot(snapshot)

Removes the specified snapshot 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:snapshot – The snapshot to unmanage.