The backup center of Container Service for Kubernetes (ACK) provides an end-to-end solution for backing up, restoring, and migrating stateful and stateless applications. It also supports disaster recovery and application migration for stateful applications in hybrid cloud and multi-cluster environments. Use the backup center to periodically back up applications and data in an ACK cluster, restore them at a point in time, or migrate them across zones and regions.
How it works
The backup center routes backup operations to one of three underlying technologies based on the volume type.
Application backup (Kubernetes resource YAML files)
-
Velero captures the Kubernetes resource definitions (YAML files) for your applications.
-
The backup files are uploaded to the specified Object Storage Service (OSS) bucket.
-
During restoration, Velero reads the YAML files from OSS and recreates the resources in the target cluster.
Disk volume backup
-
The backup center triggers the Elastic Compute Service (ECS) disk snapshot feature to create a point-in-time snapshot of each disk volume.
-
During restoration, a new disk is provisioned from the snapshot.
-
For cross-region scenarios, disk snapshots created in region A are replicated to region B, then restored from the replicated snapshots.
Cross-region data synchronization supports disk volumes only.
For more information, see Create a snapshot manually and Create a data disk from a snapshot.
Other volume types (NAS, OSS, CPFS, local disks, and open source drivers)
-
Cloud Backup backs up files from volumes that use File Storage NAS (NAS) file systems, OSS buckets, CPFS file systems, local disks, and open source off-tree drivers such as NFS and Ceph.
-
Cloud Backup also supports hybrid cloud scenarios, backing up data from on-premises storage to the cloud.
-
During restoration, Cloud Backup restores data to the corresponding storage. If StorageClass conversion is used, the CSI provisioner creates and mounts persistent volumes (PVs) of the specified StorageClass before Cloud Backup writes data to the underlying storage.
When the backup center backs up NAS, OSS, and local disk volumes, Cloud Backup occupies NAS and OSS storage bandwidth. Schedule backups during off-peak hours to minimize impact on production workloads. For more information, see What is Cloud Backup?.
Billing
The backup center feature is free of charge. Costs arise from the underlying storage and backup services it relies on.
| Charged service | Applies when | Storage type covered | Pricing details |
|---|---|---|---|
| OSS storage | OSS bucket stores Kubernetes resource YAML backup files | Application (YAML) backups | OSS billing |
| ECS snapshots | Disk volumes are backed up using ECS disk snapshots | Disk volumes | Snapshot billing |
| Cloud Backup | All volume types other than disk volumes (NAS, OSS, CPFS, local disks, open source drivers) | NAS, OSS, CPFS, local disks, open source drivers | Cloud Backup pricing |
Starting 11:00 (UTC+8) on October 12, 2023, storage fees and feature usage fees for the instant access feature are no longer charged. If you use PL0 ESSD, PL1 ESSD, PL2 ESSD, PL3 ESSD, or ESSD AutoPL disks, snapshots created during backups have the instant access feature enabled by default. For more information, see Use the instant access feature.
Use cases
Back up and restore applications within and across same-region clusters
Back up and restore applications and data within an ACK cluster or across ACK clusters in the same region. After creating a backup in the backup cluster, restore applications directly in the restore cluster or use StorageClass conversion to change the StorageClass of restored volumes.
Supported capabilities:
-
Point-in-time full snapshots
-
Periodic incremental backup
-
Fast snapshots for TB-level disks
Supported storage types:
| Category | Types |
|---|---|
| Local storage | Local disks |
| Block storage | Disks |
| File storage | NAS and CPFS |
| Object storage | OSS |
Recover applications across regions
Back up and restore applications and data across ACK clusters in different regions. After creating a backup in the backup cluster, restore data directly in the restore cluster.
Supported capabilities:
-
Point-in-time full snapshots
-
Periodic incremental backup
-
Fast snapshots for TB-level disks
Supported storage types:
| Category | Types |
|---|---|
| Block storage | Disks only |
Back up on-premises applications to the cloud
Connect Kubernetes clusters running in on-premises data centers or on other cloud platforms to registered clusters. The backup center periodically backs up applications and data to the cloud and restores them in the specified ACK clusters. For more information about connecting Kubernetes clusters to registered clusters, see Clusters.
Supported capabilities:
-
Point-in-time full snapshots
-
Periodic incremental backup
-
Incremental data minimization, data deduplication, and data compression
Supported on-premises storage types:
| Category | Types |
|---|---|
| Block storage | SAN (Storage Area Network), Ceph OBD, and LVM (Logical Volume Manager) |
| File systems | HostPath, NFS, NetApp, GlusterFS, and CephFS |
| Object storage | Ceph S3 |
Restore applications from YAML file backups
Back up and restore applications — including the YAML files of persistent volume claims (PVCs) and PVs — across ACK clusters within the same region, ACK clusters in different regions, and registered clusters. Unless you explicitly exclude PVCs and PVs when you back up or restore applications, Velero restores all PVCs and PVs used by the applications and associates them with the original data sources (same disk IDs or NAS mount targets).
-
Applications can share data stored in shared volumes such as NAS and OSS. Make sure reads and writes are consistent when multiple applications access the same volume concurrently. For volumes that cannot be shared, such as disk volumes, unmount the volumes before restoration to avoid resource contention or restoration failures.
-
Install the corresponding volume plug-in in the restore cluster and make sure the cluster meets mounting requirements. For example, disks cannot be mounted across zones, and NAS file systems are accessible only through internal networks.
Back up and restore disk volumes between PVCs
Back up and restore disks within an ACK cluster, across ACK clusters in the same region, or across ACK clusters in different regions. After creating a backup in the backup cluster, use the VolumeSnapshot resource in the cluster to launch a new application, or use the backup center to create new disk PVs and PVCs from backups in another cluster. Add prefixes or suffixes to PVC names to avoid resource contention during restoration.
Supported capabilities:
-
Point-in-time full snapshots
-
Periodic incremental backup
-
Fast snapshots for TB-level disks
Supported storage types:
| Category | Types |
|---|---|
| Block storage | Disks only |
Key concepts
| Term | Description |
|---|---|
| Crash-consistent backup | Does not guarantee that the application cache and operating system cache are backed up in the storage. |
| Application-consistent backup | Guarantees that the application cache and operating system cache are backed up in the storage. |
| Cross zones | Application backup and restoration across zones. |
| Cross regions | Application backup and restoration across regions. |
| Snapshot | Snapshots of file systems and disks. |
| Fast snapshot | Snapshots of TB-level disks created within a few seconds. |
| Restoration | Restoration of applications and data. |
| Application backup | Backup of metadata of applications, services, and configurations. |
| Data protection | Backup of volume resources and associated underlying storage data. |