You can copy snapshots within the same region or across regions to flexibly and reliably back up data. You can use the Copy and Encrypt feature to encrypt snapshot copies when you copy snapshots. This improves data security. This topic describes how to copy snapshots within the same region or across regions.
Prerequisites
A snapshot is created. For more information, see Create a snapshot.
Key Management Service (KMS) is activated before you copy a snapshot to create an encrypted snapshot copy. For more information, see the Activate KMS section of the "Overview" topic.
The snapshot you want to copy is a standard snapshot. You cannot copy archive snapshots.
Use scenarios
Snapshot replication is applicable to the following scenarios:
DevOps scenarios
You can copy snapshots to start business in new regions or migrate business systems to new regions. This helps you reduce O&M costs and improve data availability.
In-region or cross-region backup scenarios
Snapshot replication helps meet the requirements for compliance audit and improve business reliability. In the event of a disaster, you can restore your business by using snapshot copies in another region. This reduces the recovery time objective (RTO) and recovery point objective (RPO).
The following table describes the differences between copy scenarios and copy and encryption scenarios.
Scenario | Usage | Security | Procedure |
Copy scenarios | Copy unencrypted snapshots across regions to back up data or create cloud disks based on the unencrypted snapshot copies in the destination regions. | You can directly access unencrypted snapshots. | |
Copy and encryption scenarios |
| You can access encrypted snapshots only by using encryption keys. This can protect sensitive snapshot data from unauthorized access. Encrypted snapshots provide a higher level of security than non-encrypted snapshots. This ensures better protection for data privacy and security. |
Billing
This section contains important information that you must take note of. To prevent unexpected costs, read the following information carefully.
When you copy the snapshots of a cloud disk, take note of the scenarios and scopes described in the following table. The copy scenarios and scopes not described in the following table are not supported.
Scenario | Scope | Snapshot copy size | Fee |
Copy unencrypted snapshots | Across regions | The first snapshot copy of a cloud disk in each destination region is a full copy. All subsequent snapshot copies of the disk in the same region are incremental copies that contain only the data that changed since the previous copy. |
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Copy unencrypted snapshots and encrypt the snapshot copies | Within the same region | Each time you copy a snapshot of a cloud disk, the snapshot copy size equals the disk size. For example, each time you copy a 10-GB snapshot of a 40-GB cloud disk, the snapshot copy is 40 GB in size instead of 10 GB. |
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Across regions |
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Copy encrypted snapshots and encrypt the snapshot copies | Within the same region | The first snapshot copy of a cloud disk in the region is a full copy. Subsequent snapshot copies of the disk in the region are incremental copies that contain only the data that changed since the previous copy. For a cloud disk, the first snapshot copy generated after the encryption key for snapshot copies in the region is changed is also a full copy. Subsequent snapshot copies of the disk are incremental copies. |
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Across regions | For each destination region, the mechanism is the same as that for copying encrypted snapshots and encrypting the snapshot copies within the same region. |
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Snapshot storage fee
After you copy a snapshot to a region, you are charged a storage fee for the snapshot copy in the region. For information about the formula used to calculate the fee, see Snapshots.
Data transfer fee
The following formula is used to calculate the data transfer fee:
Data transfer unit price for snapshot replication: To view the unit price of snapshot replication data transfers between regions, go to the Elastic Compute Service product page, click the Pricing tab, and then scroll down and click the Snapshot tab.
Snapshot size: Unit: GB. For information about how to view the snapshot size, see View the snapshot size.
ImportantTo copy an unencrypted snapshot and encrypt the snapshot copy, the snapshot copy size in the preceding formula is the disk size.
KMS encryption fee
Alibaba Cloud KMS allows you to encrypt cloud resources by using default keys free of charge. You are not charged key fees when you use default keys. For information about KMS fees in other scenarios, see Billing.
Limits
You cannot copy the tags and retention periods of source snapshots to snapshot copies.
NoteIf you copy a snapshot in the ECS console, the snapshot copy is permanently retained. If you copy a snapshot by calling the CopySnapshot operation, you can specify a retention period for the snapshot copy.
The ID of a snapshot copy is different from the ID of the source snapshot. You cannot use the snapshot copy to roll back cloud disks created from the source snapshot.
Snapshot copies do not support the instant access feature.
Standard snapshots can be copied only as standard snapshots.
Procedure
Go to ECS console - Snapshots.
In the top navigation bar, select the region and resource group of the resource that you want to manage.
On the Disk Snapshots tab, find the snapshot that you want to copy and choose
> Copy Snapshot in the Actions column. In the Copy Snapshot dialog box, configure parameters based on the copy scenario. The following table describes the parameters.
Copy scenarios
Parameter
Description
Snapshot Name
Enter a name for the new snapshot.
Destination Region
Select a destination region that is different from the region where the source snapshot resides.
Copy Type
Select Copy.
Advanced Settings (Optional)
Description
Enter a description for the new snapshot. To facilitate management, we recommend that you enter relevant information, such as the purpose and environment of the new snapshot.
Tag
To facilitate management, specify the tags that you want to add to the new snapshot.
NoteYou cannot copy the tags of the source snapshot to the new snapshot.
Copy and encryption scenarios
Parameter
Description
Snapshot Name
Enter a name for the new snapshot.
Destination Region
Select a destination region. The selected region can be the region of the source snapshot or a different region.
Copy Type
Select Copy and Encrypt.
NoteSnapshots that are created for encrypted cloud disks are also encrypted. If the snapshot that you want to copy is an encrypted snapshot, select Copy and Encrypt.
Encryption Key
You can select the service key of the destination region or a customer master key (CMK) that is created in KMS from the drop-down list.
NoteFor more information about encryption keys, see the Encryption keys section of the "Encrypt cloud disks" topic.
If you select a CMK, make sure that the CMK meets the region and permission requirements. For more information, see the Limits section of the "Encrypt cloud disks" topic.
Advanced Settings (Optional)
Description
Enter a description for the new snapshot. To facilitate management, we recommend that you enter relevant information, such as the purpose and environment of the new snapshot.
Tag
To facilitate management, specify the tags that you want to add to the new snapshot.
NoteYou cannot copy the tags of the source snapshot to the new snapshot.
Confirm the information and click Confirm. The system copies the specified snapshot.
(Optional) Switch to the destination region and view information about the new snapshot.
When the new snapshot is being created in the destination region, Processing is displayed in the Progress column. You can click Delete Snapshot in the Actions column to cancel the snapshot copying task and delete the new snapshot.
When the snapshot copying task is completed, Available is displayed in the Progress column of the new snapshot.
To view the ID of the source snapshot, move the pointer over Snapshot Copy in the Creation Method column of the new snapshot.
To determine whether the new snapshot is encrypted and view the encryption key, view the value in the Encrypted/Unencrypted column.