Restoring virtual machines

You restore an OpenShift API for Data Protection (OADP) Backup custom resource (CR) by creating a Restore CR.

You can add hooks to the Restore CR to run commands in init containers, before the application container starts, or in the application container itself.

Creating a Restore CR

You restore a Backup custom resource (CR) by creating a Restore CR.

Prerequisites

  • You must install the OpenShift API for Data Protection (OADP) Operator.

  • The DataProtectionApplication CR must be in a Ready state.

  • You must have a Velero Backup CR.

  • Adjust the requested size so the persistent volume (PV) capacity matches the requested size at backup time.

Procedure

  1. Create a Restore CR, as in the following example:

    1. apiVersion: velero.io/v1
    2. kind: Restore
    3. metadata:
    4.   name: <restore>
    5.   namespace: openshift-adp
    6. spec:
    7.   backupName: <backup> (1)
    8.   includedResources: [] (2)
    9.   excludedResources:
    10.   - nodes
    11.   - events
    12.   - events.events.k8s.io
    13.   - backups.velero.io
    14.   - restores.velero.io
    15.   - resticrepositories.velero.io
    16.   restorePVs: true
    1Name of the Backup CR.
    2Optional. Specify an array of resources to include in the restore process. Resources might be shortcuts (for example, ‘po’ for ‘pods’) or fully-qualified. If unspecified, all resources are included.

  2. Verify that the status of the Restore CR is Completed by entering the following command:

    1. $ oc get restore -n openshift-adp <restore> -o jsonpath='{.status.phase}'

  3. Verify that the backup resources have been restored by entering the following command:

    1. $ oc get all -n <namespace> (1)
    1Namespace that you backed up.

Creating restore hooks

You create restore hooks to run commands in a container in a pod while restoring your application by editing the Restore custom resource (CR).

You can create two types of restore hooks:

  • An init hook adds an init container to a pod to perform setup tasks before the application container starts.

    If you restore a Restic backup, the restic-wait init container is added before the restore hook init container.

  • An exec hook runs commands or scripts in a container of a restored pod.

Procedure

  • Add a hook to the spec.hooks block of the Restore CR, as in the following example:

    1. apiVersion: velero.io/v1
    2. kind: Restore
    3. metadata:
    4.   name: <restore>
    5.   namespace: openshift-adp
    6. spec:
    7.   hooks:
    8.     resources:
    9.       - name: <hook_name>
    10.         includedNamespaces:
    11.         - <namespace> (1)
    12.         excludedNamespaces:
    13.         - <namespace>
    14.         includedResources:
    15.         - pods (2)
    16.         excludedResources: []
    17.         labelSelector: (3)
    18.           matchLabels:
    19.             app: velero
    20.             component: server
    21.         postHooks:
    22.         - init:
    23.             initContainers:
    24.             - name: restore-hook-init
    25.               image: alpine:latest
    26.               volumeMounts:
    27.               - mountPath: /restores/pvc1-vm
    28.                 name: pvc1-vm
    29.               command:
    30.               - /bin/ash
    31.               - -c
    32.             timeout: (4)
    33.         - exec:
    34.             container: <container> (5)
    35.             command:
    36.             - /bin/bash (6)
    37.             - -c
    38.             - "psql < /backup/backup.sql"
    39.             waitTimeout: 5m (7)
    40.             execTimeout: 1m (8)
    41.             onError: Continue (9)
    1Optional: Array of namespaces to which the hook applies. If this value is not specified, the hook applies to all namespaces.
    2Currently, pods are the only supported resource that hooks can apply to.
    3Optional: This hook only applies to objects matching the label selector.
    4Optional: Timeout specifies the maximum amount of time Velero waits for initContainers to complete.
    5Optional: If the container is not specified, the command runs in the first container in the pod.
    6This is the entrypoint for the init container being added.
    7Optional: How long to wait for a container to become ready. This should be long enough for the container to start and for any preceding hooks in the same container to complete. If not set, the restore process waits indefinitely.
    8Optional: How long to wait for the commands to run. The default is 30s.
    9Allowed values for error handling are Fail and Continue:

    • Continue: Only command failures are logged.

    • Fail: No more restore hooks run in any container in any pod. The status of the Restore CR will be PartiallyFailed.