An ECS image stores information that you need for creating an ECS instance. You must select an image when you create an ECS instance. An image works as a copy that stores data from one or more disks. An ECS image may store data from a system disk or from both system and data disks.

Image types

The following table describes the types of ECS images based on their sources.
Type Description Price
Public image Public images provided by Alibaba Cloud are licensed, secure, and stable. Public images include Windows Server system images and mainstream Linux system images. For more information, see Overview.
Only Windows Server and Red Hat Enterprise Linux public images are billed. Check the actual fees when you use them to create instances. The Windows Server and Red Hat Enterprise Linux public images are licensed and maintained by Microsoft and Red Hat, respectively.
  • Red Hat Enterprise Linux: Fees are calculated based on the instance type.
  • Windows Server: Fees are calculated based on the instance type.

Other images: free of charge.
Custom image Custom images are created from instances or snapshots, or imported from your local device. Only the creator of a custom image can use, share, copy, and delete the image. For more information, see Lifecycle of a custom image.
Custom image fees are billed in the following situations:
  • Daily-use fees. The daily-use fees are equal to the fees incurred by the snapshot where the custom image is created from. Snapshots are billed based on the storage space usage.
  • Instance creation fees. When you use a custom image to create an instance, fees are billed as follows:
    • If the custom image is created based on an Alibaba Cloud Marketplace image, the custom image fees are equal to the total fees incurred by the Alibaba Cloud Marketplace image and the corresponding snapshot.
    • If the custom image is created based on a free image, the custom image fees are equal to the fees of the corresponding snapshot.
For more information, see Billing overview and Image FAQ.
Shared image Shared images are images shared to you by other Alibaba Cloud accounts. For more information, see Share images. If a shared image is provided by Alibaba Cloud Marketplace, the shared image is billed based on the pricing standards of the independent software vendors (ISVs).
Alibaba Cloud Marketplace image
Alibaba Cloud Marketplace images are classified into the following types based on the ISVs:
  • Images provided by Alibaba Cloud accounts
  • Images provided by ISVs and licensed by Alibaba Cloud Marketplace
An Alibaba Cloud Marketplace image contains an operating system and pre-installed software. The operating system and pre-installed software are tested and verified by the ISVs and Alibaba Cloud to ensure that the image is safe to use. For more information, see Marketplace images.
Alibaba Cloud Marketplace images are billed based on the pricing standards of the ISVs.

Lifecycle of a custom image

After you create or import a custom image, the image is in the Available state. You can then use the image to create ECS instances, share the image to another Alibaba Cloud account, or copy the image to another region. You can also delete images that you no longer need. The following figure shows the lifecycle of a custom image.Lifecycle of a custom image

Create a custom image

After you create an ECS instance by using an existing image, you can configure the instance as needed. For example, you can install software and deploy projects on the instance, and create a custom image from the instance. For more information, see Create a custom image by using an instance. Instances created from the custom image contain all the custom items that you have configured. For more information, see Create an ECS instance by using a custom image.

You can create a custom image from a system disk snapshot or from a system disk snapshot and one or more data disk snapshots. For more information, see Create a custom image from a snapshot.

You can also import a custom image from a local device. For more information, see Image import procedure.

Share and copy a custom image

Each image belongs to a region. For example, if you create a custom image in the China (Beijing) region, you can use the image to create ECS instances only in this region.

  • When you share the image to another Alibaba Cloud account, this account can use the image only in the China (Beijing) region. If you want to share the image to an Alibaba Cloud account that needs to use the image in a different region, copy the image to the destination region, and then share the image to the target Alibaba Cloud account. For more information, see Share images.
  • If you want to use the image in another region, copy the image to that region. The image copy is assigned a unique UID. It is independent of the original image. For more information, see Copy custom images.

Change the image of an ECS instance

After you create an ECS instance, you can change its operating system by replacing the image of the system disk.

Delete a custom image

You can delete customs images that you no longer need. After a custom image is deleted, you can no longer use it to created ECS instances. You cannot re-initialize disks of an ECS instance that is created from the image. For more information, see Reinitialize a cloud disk.

A custom image created from an ECS instance consists of the snapshots of disks that are attached to the instance. If you delete a custom image, snapshots contained in the image will not be deleted. If you do not want to keep the snapshots, navigate to the Snapshots page and delete the snapshots. For more information, see Delete custom images.

API operations

You can also call API operations to manage images. For more information, see API overview.