Use a system disk snapshot to create a custom image to quickly replicate the environment of an ECS instance - Elastic Compute Service

You can create a custom image from a snapshot of an existing system disk. This custom image includes the operating system, software, configurations, and data from your ECS instance. You can then use the custom image to create new ECS instances with the same environment as the original instance to quickly replicate your system.

Prerequisites

You have created a system disk snapshot. For more information, see Create a snapshot.
Ensure you have removed sensitive data from the snapshot.

Considerations

Before creating a custom image from a snapshot, consider the following:

Item	Description
Region restrictions	The snapshot and the resulting custom image must be in the same region. To use an image across regions, first create the custom image, and then copy the custom image to another region.
Snapshot restrictions	The snapshot must be a system disk snapshot. You cannot create a custom image from a data disk snapshot. You cannot create a custom image from a shared snapshot. You can use both encrypted and unencrypted snapshots to create a custom image. A custom image created from an encrypted snapshot is encrypted by default, using the same encryption key as the source snapshot.
Billing	Using snapshots incurs storage fees. For more information, see Snapshot billing.
Creation period	Image creation time depends on the size of the underlying cloud disk. The image is available only after snapshots for all associated cloud disks are complete.
Other considerations	The expiration or release of the source ECS instance does not affect the custom image created from its snapshot, nor does it affect any ECS instances created from that image.

Procedure

You can create a custom image from a system disk snapshot on the Images page, the Instance Details page, or the Snapshots page. This example uses the Snapshots page.

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 target snapshot whose Disk Type is System Disk. In the Actions column, click Create Custom Image.

In the Create Custom Image dialog box, configure the following parameters:

Parameter	Description	References
Name	Enter a name for the custom image.	Not applicable
(Optional) Image Check	Image Check verifies if an imported custom image is valid and can be used to create fully functional ECS instances. Check After Creation is selected by default. The check runs immediately after the image is created. After the check is complete, you can view the details in the Check Result column of the custom image list. If any issues need to be fixed, you can use the ACS-ECS-RepairImage public template of CloudOps Orchestration Service (OOS) for one-click repair, or fix them manually based on the suggestions in the image details. Note Image Check is supported only for specific operating systems. For more information, see Check and fix custom images.	Check and fix custom images
(Optional) Image Family	You can select an image family when you create the custom image. Custom images assigned to an image family can be deprecated or restored, enabling smooth image updates and rollbacks.	Image family
(Optional) Snapshot Settings	To include data disks in the image, select increasesData Disk and click increases to specify one or more data disk snapshot IDs. The resulting custom image will contain data disks created from the snapshots you add. If you do not add a data disk snapshot, a new empty data disk with a default capacity of 5 GiB is created by the system. If you add a data disk snapshot, the new data disk has the same capacity as the snapshot.	Create a disk from a snapshot
Billing of Snapshots	If the source snapshot has a configured automatic release time, you must select I have read the Billing of Snapshots. Important The selected snapshot has a configured automatic release time. To ensure that the snapshot is automatically released as scheduled, you must manually delete all images created from this snapshot before it expires. If you do not delete the related images, the snapshot cannot be automatically released and will continue to incur fees.	Snapshot billing
(Optional) Description	Enter a description for the custom image.	Not applicable
(Optional) Tag	Select a tag. Optional: This parameter is optional in most scenarios. Required: This parameter is required if the RAM user you are using is granted a RAM policy that enforces tag binding. Otherwise, a permission error is reported.	Tags
(Optional) Resource Group	To manage the custom image based on criteria such as purpose or permissions, select a resource group.	Resource groups

Click OK and wait for the image creation to complete.