镜像

An image is a template file used to create a VM instance or volume. Images are categorized into system images and volume images.
  • A system volume image can be of the ISO or Image type while a data volume image can only be of the Image type.
  • Image-type images can be in raw or qcow2 format.
  • Images are stored on backup storages. When an image is used to create a VM instance or volume, the image is downloaded to a primary storage and cached there.
The platform type of an image decides whether the VM instances that are created based on the image use KVM VirtIO drivers, including VirtIO disk drivers and VirtIO NIC drivers. The following lists the available platform types of an image:
  • Linux: uses VirtIO drivers.
  • Windows: does not use VirtIO drivers. QEMU is used to emulate devices. The operating system (OS) contained in the image is Windows that does not install VirtIO.
  • WindowsVirtio: uses VirtIO drivers. The operating system (OS) contained in the image is Windows that has installed VirtIO drivers, including VirtIO disk drivers and VirtIO NIC drivers.
  • Other: does not use VirtIO drivers. QEMU is used to emulate devices. The operating system (OS) contained in the image can be of any type and version. This platform type allows compatibility with earlier versions of an OS that does not support VirtIO drivers, such as RHEL 5.8.
  • Paravirtualization: uses VirtIO drivers. The operating system (OS) contained in the image can be of any type and version that has installed VirtIO drivers.
You can add an image by specifying an image URL or uploading a local file:
  • URL: Enter a specified URL to add an image. You can enter a URL by using either of the following syntax:
    • A URL that starts with http or https:
      • Syntax: http://host[:port]/path/file or https://host[:port]/path/file.
    • A URL that starts with ftp:
      • Syntax that does not specifies the user: ftp://hostname[:port]/path/file.
      • Syntax that specifies the user: ftp://user:password@hostname[:port]/path/file.
    • A URL that starts with sftp:
      • Syntax that specifies the user identity: sftp://user:password@hostname[:port]/path/file
      • User-identity-free syntax: sftp://user@hostname[:port]/path/file.
    • The absolute path of an image file that is stored on a backup storage. The backup storage that stores the image file can be an ImageStore backup storage.

      Syntax: file:///path/file

    Note:
    • The image file to be added to the destination backup storage must exist and the backup storage needs to have access to the URL of the image file.
    • If you enter a URL that starts with sftp and does not specify user identity, make sure that you enable password-free SSH login to the server that stores the image file.
    • For the progress bar and resumption from breakpoint features:
      • If you use an ImageStore backup storage, a progress bar will appear to display the upload progress. In addition, upload resumption from breakpoints is also supported.
      • If you use a Ceph backup storage, a progress bar will appear to display the upload progress. However, upload resumption from breakpoints is not supported.
    • If you specify a URL with the file:/// syntax to add an image:
      • Ceph backup storage does not support the file:/// syntax.
      • The three forward slashes (/) in file:/// represents the an absolute path of a file on a backup storage. For example, if you specify the URL file:///opt/dvd/image-1.4.qcow2, you add the image file named image-1.4.qcow2 in the /opt/dvd path of a backup storage to the Cloud.
  • Local File: Select a local image file that the current browser can access and upload the image file to the specified backup storage. The backup storage that stores the image file can be an ImageStore or Ceph backup storage.
    Note: If you upload a local image file, the local browser serves as a transfer station. Do not refresh or close the browser or stop management node services. Otherwise, the image addition may fail.