Back up data in the same region or across regions and change the snapshot encryption status by copying a snapshot - Elastic Compute Service

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 a snapshot 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.

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.
Inter-region or cross-region backup scenarios
Snapshot replication helps meet the requirements for compliance audit and improvement of business reliability. In the event of a disaster, you can restore your business systems 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	You can 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 scenarios
Copy and encryption scenarios	You can copy unencrypted snapshots within the same region to create encrypted snapshot copies. The encrypted snapshot copies that reside in the same region as the source snapshots can use different encryption keys. You can copy unencrypted snapshots across regions to create encrypted snapshot copies. You can use the encrypted snapshot copies to back up data or create cloud disks in the destination regions. The encrypted snapshot copies that reside in different regions from the source snapshots can use different encryption keys.	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.	Copy and encryption scenarios

Precautions

When you copy snapshots, take note of the items described in the following table.

Item	Description
Replication fee	If you copy a snapshot from one region to another region, you are charged a data transfer fee for the snapshot replication and a storage fee for the new snapshot (snapshot copy) in the destination region. For more information, see Snapshots. Note The first time you copy a snapshot of a cloud disk, the snapshot copy is a full copy that contains all data stored on the cloud disk. All subsequent snapshot copies of the cloud disk in the same region are incremental copies, and each incremental copy contains only the data that changed since the previous copy. You are charged for snapshots based on the snapshot size. Incremental snapshot copies can significantly reduce the size of data to be copied. When you copy a snapshot, you can set the copy mode to Copy and Encrypt to encrypt the snapshot copy by using a KMS key. For information about the billing of KMS keys, see Billing.
Replication efficiency	You can copy a snapshot faster than an image and use snapshot replication to bypass capacity constraints. If you want to copy a large image, such as an image larger than 2 TiB in size, we recommend that you copy the associated snapshots to the destination region and create an image based on the snapshot copies in the region. For information about how to copy a snapshot, see the procedure described in this topic. For information about how to create an image, see Create a custom image from a snapshot.
Limits	Tags and retention periods are not copied from source snapshots to snapshot copies. Note If 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. The snapshot copy cannot be used to roll back cloud disks created from the source snapshot. Snapshot copies do not support the instant access feature.

Procedure

Log on to the ECS console.
In the left-side navigation pane, choose Storage & Snapshots > Snapshots.
In the top navigation bar, select the region and resource group to which the resource belongs.
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. Note You 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. Note Snapshots 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. Note For 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. Note You cannot copy the tags of the source snapshot to the new snapshot.

Confirm the information and click Confirm. The system copies the specified snapshot.
Note
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.
1. In the upper-left corner of the top navigation bar, select the destination region. On the Snapshots page, find the new snapshot.
2. In the Actions column, click Delete Snapshot.
(Optional) Switch to the destination region and view information about the new snapshot.
- When the snapshot copying task is completed, Available is displayed in the Progress column corresponding to the new snapshot, as shown in the red box labeled ① in the preceding figure.
- To view the ID of the copied snapshot, move the pointer over Snapshot Copy in the Creation Method column corresponding to the new snapshot, as shown in the red box labeled ② in the preceding figure.
- To determine whether the new snapshot is encrypted and view the encryption key, view the value in the Encrypted/Unencrypted column, as shown in the red box labeled ③ in the preceding figure.