An Elastic Compute Service (ECS) image provides information necessary to create an ECS instance. You must select an image when you create an ECS instance. An image is a copy of data from one or more disks. An instance image can contain data from just a system disk or from both system and data disks.

Image types

ECS images are classified into public images, custom images, shared images, and Alibaba Cloud Marketplace images based on image sources. image-type
  • Public images

    Public images provided by Alibaba Cloud are licensed, secure, and stable. Public images for Windows Server operating systems and mainstream Linux operating systems are provided. For more information, see Overview.

  • Custom images

    Custom images are created from instances or snapshots or imported from your computer. For more information, see Overview.

  • Shared images

    Shared images are shared to you by other Alibaba Cloud accounts. Images shared to an account do not count against the image quota for the account. The account does not incur charges for images shared to it. For more information, see Share or unshare a custom image.

  • Alibaba Cloud Marketplace images

    Alibaba Cloud Marketplace images are classified into the following types based on their providers:

    • Images provided by Alibaba Cloud
    • Images provided by independent software vendors (ISVs) that are 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 thoroughly tested and verified by the ISV and Alibaba Cloud to ensure that the image is safe to use. For more information, see Alibaba Cloud Marketplace images.

Image prices

You may be charged for the use of images depending on their type.

Image type Price
Public image

Some public images are billed, and others are free of charge.

  • The prices of Windows Server public images are subject to the instance types that you select. The price information is displayed on the instance buy page when you create an instance in the ECS console.
  • Red Hat Enterprise Linux public images are paid images. The price information is displayed on the buy page when you create an instance in the ECS console.
  • Public images that run other operating systems are free of charge.
Note Windows Server public images are licensed and maintained by Microsoft. Red Hat Enterprise Linux public images are licensed and maintained by Red Hat.
Custom image

Custom images are created from snapshots. You are charged for the snapshots contained in the custom images based on the size and storage duration of snapshots. For more information, see Snapshots.

Custom images are billed differently in the following situations:

  • If a custom image is derived from a free image, you are charged for the snapshots contained in the custom image.
  • If a custom image is derived from a paid image, you are charged for the snapshots contained in the custom image. If you use the custom image to create an instance, you are also charged for the image. If you do not use the custom image when you create an instance, you are not charged for the image.
Note If a custom image is derived from an Alibaba Cloud Marketplace image, the custom image is billed in the same manner as the Alibaba Cloud Marketplace image.
Shared image

Shared images are billed differently in the following situations:

  • If an image shared to you by another Alibaba Cloud account is derived from a free image, you can use the shared image free of charge.
  • If an image shared to you by another Alibaba Cloud account is derived from a paid image and you create an instance from the shared image, you are charged for the shared image.
Note If a shared image is derived from an Alibaba Cloud Marketplace image, the shared image is billed in the same manner as the Alibaba Cloud Marketplace image.
Alibaba Cloud Marketplace image Alibaba Cloud Marketplace images are billed based on the billing methods provided in Alibaba Cloud Marketplace.

For more information, see Billing overview and the "FAQ about the commercial availability of images" section of the Image FAQ topic.

Select and find images

You can select an image based on the region, image type, image price, operating system, and built-in software. For more information, see Select an image.

You can find an image based on its type, name, ID, or the ID of the snapshot from which the image was created. Then, you can use the image to create instances or perform other operations. For more information, see Find an image.

Replace the image of an ECS instance

After you create an instance, you can replace its operating system by replacing its system disk.

Limits

For information about the limits and quotas of images, see the "Image limits" section of the Limits topic.

API operations

You can also call API operations to manage images. For more information, see the "Images" section of the List of API operations by function topic.