Ubuntu OCI image configuration ****************************** The definition of the Ubuntu container image follows the `OCI image format specification `_. So, as with any other container image, the Ubuntu image includes enough metadata that one can inspect the image without actually running the container. Layers ------ As explained in :ref:`ubuntu-oci-container-images`, the Ubuntu container images are built from a minimal rootfs tarball that is tailored for container environments. For each Ubuntu release, you'll find a corresponding `release branch in Launchpad `_ (e.g. ``noble-24.04``) with the build recipe and a reference to the respective architecture-specific rootfs tarballs. Image index ----------- The Ubuntu container image is published with a multi-architecture image index, meaning that there will be a container image digest that will internally resolve to multiple architecture-specific digests. In other words, when pulling any Ubuntu container image by its OCI tag (e.g. ``ubuntu:24.04``), your container runtime should automatically find and pull the right container image for your host's architecture. If however, you'd like to pin a specific Ubuntu container architecture, you can pull the Ubuntu container image by its architecture-specific digest (e.g. ``ubuntu@sha256:``). Image configuration ------------------- The Ubuntu container images are built and published with the following configurations: - no default `OCI entrypoint `_, - ``bash`` is the default OCI command, - OCI labels to identify the image name (i.e. ``ubuntu``) and its release.