Volume Restore from Snapshot

Overview

Volume Restore from an existing snapshot will create a storage volume captured at a specific point in time. They serve as an essential tool for data protection, recovery, and efficient management in Kubernetes environments. This document provides step-by-step instructions to restore a volume from a previously created snapshot using Local PV LVM.

important

Volume Restore is supported only for thin volumes created from snapshots using OpenEBS v4.4.0 or later.

Requirements

Before performing the restore operation, ensure the following requirements are met:

• A volume snapshot has already been created.
• A compatible StorageClass is available for the restore operation.
• A snapshot has been created for the source volume. Follow the steps outlined in the Volume Snapshots Documentation to create a volume snapshot.
• Only thin snapshot restores are supported. To verify whether a snapshot is thin or thick, describe the LVM snapshot Custom Resource (CR) and check the spec.thinProvision field.
• The restore volume request capacity must match the snapshot logical volume (LV) size. To verify snapshot LV size, describe LVM snapshot CR and check the snapshot LV size in status.lvSize field.
• The Local PV LVM volume group name must match the snapshot’s volume group (spec.volGroup).

Example: Local PV LVM Snapshot CR

apiVersion: local.openebs.io/v1alpha1

kind: LVMSnapshot

metadata:

creationTimestamp: "2025-10-27T09:44:16Z"

finalizers:

- lvm.openebs.io/finalizer

generation: 2

labels:

kubernetes.io/nodename: worker-node-1

openebs.io/persistent-volume: pvc-dca183ae-4096-48fc-bf08-740d1c03d583

name: snapshot-cc82975a-c652-41fa-892a-744eb04ccbd1

namespace: openebs

resourceVersion: "285569"

uid: 840781e1-11e2-46af-b9de-eb88443e8cde

spec:

ownerNodeID: worker-node-1

thinProvision: true

volGroup: lvmvg

status:

lvSize: 5Gi

state: Ready

Creating a Volume Restore from an Existing Snapshot

After a snapshot is created, you can create a new volume (clone) from it. The restored volume will contain the same data as the original volume at the time the snapshot was taken.

To perform a restore, create a PersistentVolumeClaim (PVC) manifest that references the snapshot as a data source.

Command: Create a PVC from an Existing VolumeSnapshot

cat <<EOF | kubectl create -f -

apiVersion: v1

kind: PersistentVolumeClaim

metadata:

name: lvmpv-snap-restore-pvc # Specify a name for the restored volume

spec:

storageClassName: lvm-snapshot-restore-sc # Specify your StorageClass

dataSource:

name: lvmpv-snap # Specify your VolumeSnapshot name

kind: VolumeSnapshot

apiGroup: snapshot.storage.k8s.io

accessModes:

- ReadWriteOnce

resources:

requests:

storage: 5Gi

EOF

Example: PVC YAML for Volume Restore

apiVersion: v1

kind: PersistentVolumeClaim

metadata:

name: lvmpv-snap-restore-pvc //add a name for your new volume

spec:

storageClassName: lvm-snapshot-restore-sc //add your storage class name

dataSource:

name: lvmpv-snap //add your volumeSnapshot name

kind: VolumeSnapshot

apiGroup: snapshot.storage.k8s.io

accessModes:

- ReadWriteOnce

resources:

requests:

storage: 5Gi

Applying the above YAML creates a new volume from the snapshot lvmpv-snap. The restored volume is scheduled on the same node as the original volume and retains the same data and properties that existed when the snapshot was taken.

note

• The restored PVC size must match the snapshot LV size (status.lvSize).
• The restored volume must belong to the same volume group (spec.volGroup).
• Ensure that the restored volume is thin-provisioned.
• If a separate StorageClass is used for the restore operation, verify it meets the above criteria.

Verifying the Restored Volume (PVC)

Verify the restored PVC.

Command

kubectl get pvc -n openebs

Sample Output

NAME STATUS VOLUME CAPACITY ACCESS MODES STORAGECLASS AGE

lvmpv-origin-pvc Bound pvc-dca183ae-4096-48fc-bf08-740d1c03d583 5Gi RWO lvmpv-sc-2xz5t 46s

lvmpv-snap-restore-pvc Bound pvc-e9c895c0-ddbc-44ea-8f90-7fe81ba723bb 5Gi RWO lvm-snapshot-restore-sc 30s

The restored PVC (lvmpv-snap-restore-pvc) has been successfully created and bound.

Verifying the Restored Local PV LVM Volume

Verify the Local PV LVM volumes.

Command

kubectl get lvmvolume -n openebs

Sample Output

NAME VOLGROUP NODE SIZE STATUS AGE

pvc-dca183ae-4096-48fc-bf08-740d1c03d583 lvmvg worker-node-1 5368709120 Ready 82s

pvc-e9c895c0-ddbc-44ea-8f90-7fe81ba723bb lvmvg worker-node-1 5368709120 Ready 66s

The restored Local PV LVM volume (pvc-e9c895c0-ddbc-44ea-8f90-7fe81ba723bb) is created and its status is Ready.

Example: Restored LVM Volume CR

apiVersion: local.openebs.io/v1alpha1

kind: LVMVolume

metadata:

name: pvc-e9c895c0-ddbc-44ea-8f90-7fe81ba723bb

namespace: openebs

labels:

kubernetes.io/nodename: worker-node-1

spec:

capacity: "5368709120"

ownerNodeID: worker-node-1

shared: "no"

source: snapshot-cc82975a-c652-41fa-892a-744eb04ccbd1

thinProvision: "yes"

vgPattern: ^lvmvg$

volGroup: lvmvg

status:

state: Ready

note

• To prevent write failures when the thin pool becomes full, enable the following parameters in the lvm.conf file:
  • thin_pool_autoextend_threshold
  • thin_pool_autoextend_percent
• Ensure that the Volume Group (VG) has sufficient free capacity. Auto-extend will not function correctly if the VG lacks space.