Image metadata

Image metadata can help end users determine the nature of an image, and is used by associated OpenStack components and drivers which interface with the Image Service.

Metadata can also determine the scheduling of hosts. If the property option is set on an image, and Compute is configured so that the ImagePropertiesFilter scheduler filter is enabled (default), then the scheduler only considers compute hosts that satisfy that property.

	Note
	Compute's ImagePropertiesFilter value is specified in the scheduler_default_filter value in the /etc/nova/nova.conf file.

You can add metadata to Image Service images by using the --property key=value option with the glance image-create or glance image-update command. More than one property can be specified. For example:

$ glance image-update img-uuid --property architecture=arm --property hypervisor_type=qemu

Common image properties are also specified in the /etc/glance/schema-image.json file. For a complete list of valid property keys and values, refer to the OpenStack Command-Line Reference.

All associated properties for an image can be displayed using the glance image-show command. For example:

$ glance image-show myCirrosImage
+---------------------------------------+--------------------------------------+
| Property                              | Value                                |
+---------------------------------------+--------------------------------------+
| Property 'base_image_ref'             | 397e713c-b95b-4186-ad46-6126863ea0a9 |
| Property 'image_location'             | snapshot                             |
| Property 'image_state'                | available                            |
| Property 'image_type'                 | snapshot                             |
| Property 'instance_type_ephemeral_gb' | 0                                    |
| Property 'instance_type_flavorid'     | 2                                    |
| Property 'instance_type_id'           | 5                                    |
| Property 'instance_type_memory_mb'    | 2048                                 |
| Property 'instance_type_name'         | m1.small                             |
| Property 'instance_type_root_gb'      | 20                                   |
| Property 'instance_type_rxtx_factor'  | 1                                    |
| Property 'instance_type_swap'         | 0                                    |
| Property 'instance_type_vcpu_weight'  | None                                 |
| Property 'instance_type_vcpus'        | 1                                    |
| Property 'instance_uuid'              | 84c6e57d-a6b1-44b6-81eb-fcb36afd31b5 |
| Property 'kernel_id'                  | df430cc2-3406-4061-b635-a51c16e488ac |
| Property 'owner_id'                   | 66265572db174a7aa66eba661f58eb9e     |
| Property 'ramdisk_id'                 | 3cf852bd-2332-48f4-9ae4-7d926d50945e |
| Property 'user_id'                    | 376744b5910b4b4da7d8e6cb483b06a8     |
| checksum                              | 8e4838effa1969ad591655d6485c7ba8     |
| container_format                      | ami                                  |
| created_at                            | 2013-07-22T19:45:58                  |
| deleted                               | False                                |
| disk_format                           | ami                                  |
| id                                    | 7e5142af-1253-4634-bcc6-89482c5f2e8a |
| is_public                             | False                                |
| min_disk                              | 0                                    |
| min_ram                               | 0                                    |
| name                                  | myCirrosImage                        |
| owner                                 | 66265572db174a7aa66eba661f58eb9e     |
| protected                             | False                                |
| size                                  | 14221312                             |
| status                                | active                               |
| updated_at                            | 2013-07-22T19:46:42                  |
+---------------------------------------+--------------------------------------+