CSI external-snapshotter

Status and Releases

Git Repository: https://github.com/kubernetes-csi/external-snapshotter

Status: Alpha

Definitions of the min/max/recommended Kubernetes versions can be found on the sidecar page

Description

The CSI external-snapshotter is a sidecar container that watches the Kubernetes API server for VolumeSnapshot and VolumeSnapshotContent CRD objects.

The creation of a new VolumeSnapshot object referencing a SnapshotClass CRD object corresponding to this driver causes the sidecar container to trigger a CreateSnapshot operation against the specified CSI endpoint to provision a new snapshot. When a new snapshot is successfully provisioned, the sidecar container creates a Kubernetes VolumeSnapshotContent object to represent the new snapshot.

The deletion of a VolumeSnapshot object bound to a VolumeSnapshotContent corresponding to this driver with a delete reclaim policy causes the sidecar container to trigger a DeleteSnapshot operation against the specified CSI endpoint to delete the snapshot. Once the snapshot is successfully deleted, the sidecar container also deletes the VolumeSnapshotContent object representing the snapshot.

For detailed information about volume snapshot and restore functionality, see Volume Snapshot & Restore.

Usage

CSI drivers that support provisioning volume snapshots and the ability to provision new volumes using those snapshots should use this sidecar container, and advertise the CSI CREATE_DELETE_SNAPSHOT controller capability.

For detailed information (binary parameters, RBAC rules, etc.), see https://github.com/kubernetes-csi/external-snapshotter/blob/master/README.md.

Deployment

The CSI external-snapshotter is deployed as a controller. See deployment section for more details.

For an example deployment, see this example which deploys external-snapshotter and external-provisioner with the Hostpath CSI driver.