Backing up applications - OADP Application backup and restore | Backup and restore

Previewing resources before running backup and restore
Known issues

Frequent backups might consume storage on the backup storage location. Check the frequency of backups, retention time, and the amount of data of the persistent volumes (PVs) if using non-local backups, for example, S3 buckets. Because all taken backup remains until expired, also check the time to live (TTL) setting of the schedule.

You can back up applications by creating a Backup custom resource (CR). For more information, see Creating a Backup CR.

The Backup CR creates backup files for Kubernetes resources and internal images on S3 object storage.
If your cloud provider has a native snapshot API or supports CSI snapshots, the Backup CR backs up persistent volumes (PVs) by creating snapshots. For more information about working with CSI snapshots, see Backing up persistent volumes with CSI snapshots.

For more information about CSI volume snapshots, see CSI volume snapshots.

The CloudStorage API, which automates the creation of a bucket for object storage, is a Technology Preview feature only. Technology Preview features are not supported with Red Hat production service level agreements (SLAs) and might not be functionally complete. Red Hat does not recommend using them in production. These features provide early access to upcoming product features, enabling customers to test functionality and provide feedback during the development process.

For more information about the support scope of Red Hat Technology Preview features, see Technology Preview Features Support Scope.

The CloudStorage API is a Technology Preview feature when you use a CloudStorage object and want OADP to use the CloudStorage API to automatically create an S3 bucket for use as a BackupStorageLocation.

The CloudStorage API supports manually creating a BackupStorageLocation object by specifying an existing S3 bucket. The CloudStorage API that creates an S3 bucket automatically is currently only enabled for AWS S3 storage.

If your cloud provider does not support snapshots or if your applications are on NFS data volumes, you can create backups by using Kopia or Restic. See Backing up applications with File System Backup: Kopia or Restic.

PodVolumeRestore fails with a …/.snapshot: read-only file system error

The …/.snapshot directory is a snapshot copy directory, which is used by several NFS servers. This directory has read-only access by default, so Velero cannot restore to this directory.

Do not give Velero write access to the .snapshot directory, and disable client access to this directory.

Additional resources

The OpenShift API for Data Protection (OADP) does not support backing up volume snapshots that were created by other software.

Previewing resources before running backup and restore

OADP backs up application resources based on the type, namespace, or label. This means that you can view the resources after the backup is complete. Similarly, you can view the restored objects based on the namespace, persistent volume (PV), or label after a restore operation is complete. To preview the resources in advance, you can do a dry run of the backup and restore operations.

Prerequisites

You have installed the OADP Operator.

Procedure

To preview the resources included in the backup before running the actual backup, run the following command:
```
$ velero backup create <backup-name> --snapshot-volumes false (1)
```
1 Specify the value of --snapshot-volumes parameter as false.
To know more details about the backup resources, run the following command:
```
$ velero describe backup <backup_name> --details (1)
```
1 Specify the name of the backup.
To preview the resources included in the restore before running the actual restore, run the following command:
```
$ velero restore create --from-backup <backup-name> (1)
```
1 Specify the name of the backup created to review the backup resources.

The velero restore create command creates restore resources in the cluster. You must delete the resources created as part of the restore, after you review the resources.
To know more details about the restore resources, run the following command:
```
$ velero describe restore <restore_name> --details (1)
```
1 Specify the name of the restore.

You can create backup hooks to run commands before or after the backup operation. See Creating backup hooks.

You can schedule backups by creating a Schedule CR instead of a Backup CR. See Scheduling backups using Schedule CR.

Known issues

OpenShift Container Platform 4.17 enforces a pod security admission (PSA) policy that can hinder the readiness of pods during a Restic restore process.

This issue has been resolved in the OADP 1.1.6 and OADP 1.2.2 releases, therefore it is recommended that users upgrade to these releases.

For more information, see Restic restore partially failing on OCP 4.15 due to changed PSA policy.

Additional resources