Replicating Backups Across Regions

Scenarios

If data is stored in a single region, there is no geographical redundancy. Data security and service continuity cannot be ensured in the event of misoperations or network attacks. If there is an accident, enterprises face the risk of data loss and service interruption. Additionally, regulatory policies in industries such as finance and healthcare are becoming increasingly stringent, requiring key data to be backed up across regions.

With the replication function, you can quickly deploy services across regions. The new resources created from replicated backups are in the same state as the original resources when you took the backup. With cross-region replication, backups can be automatically or manually replicated to storage nodes in different regions, mitigating security risks while ensuring regulatory compliance. It is a fundamental safeguard for enterprise data management.

You can replicate backups in either of the following methods on the CBR console:

Select a backup from the backup list and manually perform a replication. This method is labor-intensive and inefficient, as only one backup can be replicated at a time. It is suitable for temporary emergency backup or single-point test verification.
Select a backup vault and manually replicate it. Alternatively, you can configure a replication policy to periodically replicate backups that have not been replicated or failed to be replicated to the destination region. A vault can contain multiple backups. You can manually replicate the vault to replicate multiple backups at a time, which is suitable for batch replication. You can also configure a replication policy to periodically replicate backups. This method is suitable for periodic replication, such as periodic compliance backup or service continuity assurance.

This section uses the first method to describe how to replicate a backup. For details about the second method, see Replicating a Vault Across Regions.

How Cross-Region Replication Works

Cross-region replication of server backup vaults and SFS Turbo backup vaults allows you to replicate backups from one region to another under the same account.

Replicas of server backups can be used to create images and provision servers. Replicas of SFS Turbo backups can be used to create file systems in the destination region.

Click to enlarge

As shown in the figure, you can back up resources in region A, replicate the backups to region B, and use the replicas to create images or SFS Turbo file systems in region B.

Billing

When you use the cross-region replication function, the replication vault purchased in the destination region is billed. For details about storage billing, see Cloud Backup and Recovery Billing Items.
When you replicate backups or vaults across regions, cross-region replication traffic is generated in the source region and is billed. The cross-region replication traffic is charged based on the size of the replicated backup. For details about traffic billing, see Cloud Backup and Recovery Billing Items.
You are advised to purchase yearly/monthly packages and traffic packages. The longer the purchase period, the greater the discount. For more information, see CBR Billing. For detailed prices, see CBR pricing details.

Prerequisites

You have purchased a replication (cross-region) vault in the destination region.

Constraints

Database server backups can be replicated across regions.
A server backup can be replicated only when it meets all the following conditions:
1. It is an ECS backup. You can check the server type in the Server Type column of the backup list.
2. It contains system disk data. You can check the disk backup in the backup details.
3. It is in the Available state. You can check the backup status in the backup list.
Only backups or backup vaults can be replicated. Replicated backups and vaults cannot be replicated again but their replicas can be used to create images or SFS Turbo file systems.
A backup can be replicated to multiple regions but can have only one replica in each destination region. The replication rule varies with the replication method:
Manual replication: A backup can be manually replicated to the destination region as long as it has no replica in that region. A backup can be manually replicated again if its replica in the destination region has been deleted.

For manual and policy-based vault replication, a vault can only be replicated to a destination region once. It cannot be replicated to that region again, even if its backups have been deleted.
Only replication-supported regions can be selected as destination regions. For details, see Table 1.
Only vaults of the same type can be selected as destination vaults. For example, if you want to replicate server backups to a different region, select a server backup vault (Protection Type set to Replication (cross-region)) in that region.

Procedure

Log in to the CBR console.
1. Log in to the management console.
2. Click in the upper left corner and select a region.
3. Click and choose Storage > Cloud Backup and Recovery. Select the corresponding backup type from the navigation pane.
Click the Backups tab and locate the desired backup. For details, see Viewing a Backup.
Choose More > Create Replica in the Operation column of the backup.

Figure 1 Creating a replica

In the displayed dialog box, configure the parameters as described in Table 1.

**Table 1** Parameter description
Parameter	Description
Name	Replica name. You can enter a custom name or use the default name resource name_xxxx. A name must contain 1 to 64 characters including digits, letters, underscores (_), or hyphens (-).
Description	Replica description. This parameter is optional. It cannot exceed 255 characters.
Destination Region	Region that the backup is replicated to. Only the regions that support replication will be displayed. For details about the supported regions, see Table 1. If the selected region contains only one project, you can directly select the region name. If the selected region has multiple projects, the default project of the region is selected. You can select another project if needed.
Destination Vault	A replication vault in the destination region If no replication vault is found in the destination region, purchase a vault for cross-region replication in the destination region by referring to Creating a Server Backup, and then select the vault. You can replicate backups to vaults in multiple destination regions. Creating replica will replicate all backups in the source vault to the destination vault.

Click OK.
After the replication is complete, you can switch to the destination region to view generated replicas. For details, see Viewing a Backup. You can then use the backups to create images or SFS Turbo file systems.