Elastic Compute Service:Create a custom image from a snapshot

Prerequisites

Before you begin, make sure that you have:

• A system disk snapshot. For details, see Create a snapshot

• Removed sensitive data (credentials, private keys, personal information) from the snapshot

Snapshot and region restrictions

Billing

Snapshots incur storage fees. For pricing details, see Snapshot billing.

If the source snapshot has an automatic release time configured, you must delete all images created from it before the release time. Otherwise, the snapshot cannot be released automatically and continues to incur fees.

Create a custom image from a snapshot

Image creation time depends on the size of the underlying cloud disk. The image becomes available after snapshots for all associated cloud disks are complete.

The custom image remains available even if the source ECS instance is released or expires. Instances created from the custom image are also unaffected.

You can create a custom image from a system disk snapshot on the Images page, the Instance Details page, or the Snapshots page. The following steps use the Snapshots page.

1. Go to ECS console - Snapshots.

2. In the top navigation bar, select the region and resource group.

3. On the Disk Snapshots tab, find a snapshot whose Disk Type is System Disk. In the Actions column, click Create Custom Image.

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

   Parameter	Required	Description
   Name	Yes	Enter a name for the custom image.
   Image Check	No	Validates whether the custom image can create fully functional ECS instances. Check After Creation is selected by default. After the check completes, view results in the Check Result column of the custom image list. To fix detected issues, use the ACS-ECS-RepairImage CloudOps Orchestration Service (OOS) template for one-click repair, or fix them manually. Note Image Check is supported only for specific operating systems. For details, see Check and fix custom images.
   Image Family	No	Assign the image to an image family for version management. Images in a family can be deprecated or restored, enabling smooth updates and rollbacks.
   Snapshot Settings	No	Include data disks in the image. Select Add Data Disk and click Add to specify data disk snapshot IDs. If you do not add a data disk snapshot, the system creates an empty data disk with a default capacity of 5 GiB. If you add a data disk snapshot, the new data disk has the same capacity as the snapshot. For details, see Create a disk from a snapshot.
   Billing of Snapshots	Conditional	If the source snapshot has an automatic release time, select I have read the Billing of Snapshots. You must manually delete all images created from this snapshot before it expires. Otherwise, the snapshot cannot be released automatically and continues to incur fees. See Snapshot billing.
   Description	No	Enter a description for the custom image.
   Tag	No	Select a tag. This parameter is optional in most scenarios. 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. See Tags.
   Resource Group	No	Select a resource group to manage the custom image by purpose or permissions. See Resource groups.

5. Click OK and wait for the image creation to complete.

6. Go to the Images page in the ECS console. Verify that the new custom image appears in the list with the expected name and status.

Next steps

After creating a custom image, you can:

• Create an instance from a custom image

• Change the operating system of an existing instance

• Share the image with other Alibaba Cloud accounts

• Copy the custom image to another region

Related information

• To create an image programmatically, use the CreateImage API operation.

• To create an image directly from a running instance, see Create a custom image from an instance.

• A custom image depends on its source snapshot. To delete the snapshot, you must first delete the custom image created from it.