How to manage images

When working with images, you can inspect various information about the available images, view and edit their properties and configure aliases to refer to specific images. You can also export an image to a file, which can be useful to copy or import it on another machine.

List available images

To list all images on a server, enter the following command:

lxc image list [<remote>:]

If you do not specify a remote, the default remote is used.

Filter available images

To filter the results that are displayed, specify a part of the alias or fingerprint after the command. For example, to show all Ubuntu 22.04 images, enter the following command:

lxc image list ubuntu: 22.04

You can specify several filters as well. For example, to show all Arm 64-bit Ubuntu 22.04 images, enter the following command:

lxc image list ubuntu: 22.04 arm64

To filter for properties other than alias or fingerprint, specify the filter in <key>=<value> format. For example:

lxc image list ubuntu: 22.04 architecture=x86_64

View image information

To view information about an image, enter the following command:

lxc image info <image_ID>

As the image ID, you can specify either the image’s alias or its fingerprint. For a remote image, remember to include the remote server (for example, ubuntu:22.04).

To display only the image properties, enter the following command:

lxc image show <image_ID>

You can also display a specific image property (located under the properties key) with the following command:

lxc image get-property <image_ID> <key>

For example, to show the release name of the official Ubuntu 22.04 image, enter the following command:

lxc image get-property ubuntu:22.04 release

Edit image properties

To set a specific image property that is located under the properties key, enter the following command:

lxc image set-property <image_ID> <key> <value>

Note

These properties can be used to convey information about the image. They do not configure LXD’s behavior in any way.

To edit the full image properties, including the top-level properties, enter the following command:

lxc image edit <image_ID>

Delete an image

To delete a local copy of an image, enter the following command:

lxc image delete <image_ID>

Deleting an image won’t affect running instances that are already using it, but it will remove the image locally.

After deletion, if the image was downloaded from a remote server, it will be removed from local cache and downloaded again on next use. However, if the image was manually created (not cached), the image will be deleted.

Configure image aliases

Configuring an alias for an image can be useful to make it easier to refer to an image, since remembering an alias is usually easier than remembering a fingerprint. Most importantly, however, you can change an alias to point to a different image, which allows creating an alias that always provides a current image (for example, the latest version of a release).

You can see some of the existing aliases in the image list. To see the full list, enter the following command:

lxc image alias list

You can directly assign an alias to an image when you copy or import or publish it. Alternatively, enter the following command:

lxc image alias create <alias_name> <image_fingerprint>

You can also delete an alias:

lxc image alias delete <alias_name>

To rename an alias, enter the following command:

lxc image alias rename <alias_name> <new_alias_name>

If you want to keep the alias name, but point the alias to a different image (for example, a newer version), you must delete the existing alias and then create a new one.

Export an image to a set of files

Images are located in the image store of your local server or a remote LXD server. You can export them to a file or a set of files though (see Image tarballs). This method can be useful to back up image files or to transfer them to an air-gapped environment.

To export a container image to a set of files, enter the following command:

lxc image export [<remote>:]<image> [<output_directory_path>]

To export a virtual machine image to a set of files, add the --vm flag:

lxc image export [<remote>:]<image> [<output_directory_path>] --vm

See Image format for a description of the file structure used for the image.