1. ImageStore
   • Image files are stored by means of image segmentation. Incremental storage is supported.
   • Snapshots and images can be created when VM instances are running or stopped.
   • When VM instances are cloned without data volumes, the VM instances that are running, paused, or stopped can be cloned.
   • When VM instances are cloned with data volumes, the VM instances that are running, paused, or stopped, and with storage types of LocalStorage, NFS, Shared Mount Point, Ceph, or Shared Block can be cloned.
   • Images can be synchronized across ImageStore backup storages within the same management network.
   • The existing images can be obtained. In addition, you can obtain the existing image files under the URL path in the backup storage.
2. SFTP
   • Only the SFTP Community edition is supported.
   • Image files are stored by means of files.
   • Snapshots and images can be created when VM instances are stopped.
   • On the backup storage, the images that you created can be accessed according to the corresponding backup storage path, and can be copied to other cloud environments for direct use.
3. Ceph
   • Image files are stored by means of Ceph distributed block storages.
   • Snapshots and images can be created when VM instances are running or stopped.
   • When VM instances are cloned without data volumes, the VM instances that are running, paused, or stopped can be cloned.
   • VM instances cannot be cloned with data volumes.
   • Images can only be exported on backup storages.

     Assume that the image path you use is ceph://bak-t-c9923f9821bf45498fdf9cdfa1749943/61ece0adc7244b0cbd12dafbc5494f0c.

     Then, run the following commands on the backup storage:

     rbd export -p bak-t-c9923f9821bf45498fdf9cdfa1749943 --image 61ece0adc7244b0cbd12dafbc5494f0c --path /root/export-test.image  # bak-t-c9923f9821bf45498fdf9cdfa1749943 is the name of the pool where the image resides. # 61ece0adc7244b0cbd12dafbc5494f0c is the image name. # /root/export-test.image is the name of the exported target file.

• When primary storages are LocalStorage, NFS, or Shared Mount Point, the default type for backup storages is ImageStore, or SFTP.
• When primary storages are NFS or Shared Mount Point, the corresponding shared directories can be manually attached to the local directories of the corresponding backup storages. In this regard, both primary storages and backup storages can use the network shared storage.
• When primary storages are Ceph, backup storages can use the primary storages in the same Ceph cluster as backup storages. In addition, backup storages can use the primary storages with the ImageStore type as backup storages.
• When primary storages are Shared Block, the default type for backup storages is ImageStore.

{   "inventories": [     {       "uuid": "31cbc4dad8da3ca6a6e3df5c1d5f233e",       "name": "test"     }   ] }

totalCapacity = backup storage's total capacity availableCapacity = totalCapacity - sum (images' actual sizes)

• Enabled:

  Indicates that images can be registered, backed up, and downloaded.

• Disabled:

  Indicates that images cannot be registered, backed up, or downloaded. Especially, if an image is only stored on a disabled backup storage, and if the image is not downloaded to image caches of primary storage, this image cannot be used to create VM instances.

• Connecting:

  Indicates that a ZStack management node is trying to establish a command channel between the node itself and a backup storage. At this stage, you cannot perform any operation on the backup storage.

• Connected:

  Indicates that the command channel between a ZStack management node and a backup storage is established successfully. At this stage, you can perform related operations on the backup storage.

• Disconnected:

  Indicates that the command channel between a ZStack management node and a backup storage is lost. At this stage, you cannot perform any operation on the backup storage.