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  4. Creating a Private Image
  5. Creating a Data Disk Image Using an External Image File

Creating a Data Disk Image Using an External Image File


A data disk image contains only your service data. You can use an external image file to create a data disk image.

You can also use a data disk image to create EVS disks and migrate your service data to the cloud.


Currently, you can create a data disk from a data disk image only during ECS creation.


  • The OS type of the data disk image must be defined, and it can either Windows or Linux.
  • The data disk has about 40 GB to 2048 GB of storage space.
  • When uploading the external image file, you must select an OBS bucket with Standard storage.
  • A data disk image can be used only once during the creation of an ECS.


You have uploaded an image file to the OBS bucket.

You can import an image file in VHD, VMDK, QCOW2, RAW, VHDX, QCOW, VDI, QED, ZVHD, or ZVHD2 format to create a private image. QCOW2 image files are recommended. If you need to import an image file in other formats, use the qemu-img tool to convert the image format before importing the image file. The image file to be imported must be a single image file. For example, you cannot use a pre-allocated image file which depends on two files: xxxx.vmdk and xxxx-flat.vmdk. Both files can be imported to the cloud platform only after being converted into common VMDK or QCOW2 files.

For details about image file format conversion, see Converting Image File Formats.


  1. Log in to the management console.
  2. Under Computing, click Image Management Service.
  3. On the Image Management Service page, click Create Image.
  4. In the Image Type and Source area, select Data disk image for Type.
  5. Select Image File for Source. Select the bucket storing the image file from the list and then select the image file.
    Figure 1 Creating a data disk image
  6. To register the image file using the Fast Create function, select Enable Fast Create.
    • Currently, this function supports only image files in ZVHD2 or RAW format.
    • For how to convert image file formats and generate bitmap files, see Quickly Importing an Image File.
    After you decide to use this function, you need to confirm whether image file is ready for creation.
    • For ZVHD2 image files: Ensure that the image file format is ZVHD2.
    • For Raw image files, bitmap files have been uploaded together with the image files.

    If image files are ready, select Image File Preparation.

  7. In the Image Information area, select an OS type.
  8. Specify the data disk size based on the image file.
  9. Enter the image name and also the description as needed.
  10. (Optional) If you want to encrypt the image, select KMS encryption and select the key to be used from the key list.

    When you use an external image file that has been uploaded to your OBS bucket to create a data disk image, you can enable KMS encryption and a key to encrypt the image.

  11. Click Create Now.
  12. Confirm the parameters and click Submit.