Changed Block Tracking
Status
| Status | Min K8s Version | Max K8s Version | Min CSI Version | Max CSI Version |
|---|---|---|---|---|
| Alpha | 1.33 | - | v1.10.0 | - |
Overview
This optional feature provides a secure mechanism to obtain metadata on the allocated blocks of a CSI VolumeSnapshot, or the changed blocks between two arbitrary pairs of CSI VolumeSnapshot objects of the same PersistentVolume. See Kubernetes Enhancement Proposal 3314 for full details.
A CSI driver must advertise its support for this feature by specifying the
SNAPSHOT_METADATA_SERVICE capability in the response of the
GetPluginCapabilities
RPC (part of the
CSI Identity Service),
and must implement the
CSI SnapshotMetadata Service.
CSI drivers that implement this feature should deploy the external-snapshot-metadata sidecar and create the associated Snapshot Metadata Service CR.
The external-snapshot-metadata sidecar implements the server side of the
Kubernetes SnapshotMetadata Service API.
Backup applications obtain VolumeSnapshot metadata directly from the sidecar
through this API, bypassing the Kubernetes API server for the most part.
Backup application developers should refer to the Usage
and Resources
sections of the sidecar documentation for details.