Containers

The following features, enhancements, and changes related to containers are introduced in this Oracle Linux 9 release.

Podman Updated to version 5.2

Podman is updated to version 5.2. The components for Podman are in the container-tools package.

Notable features and changes include the following:

  • Using Podman and Buildah you can now add Open Container Initiative artifacts manifests to image indexes.

    buildah manifest add includes the following options:

    • --artifact Creates artifact manifests.

    • --artifact-type, --artifact-config-type, --artifact-layer-type, --artifact-exclude-titles, and --subject specifies the contents of the artifact manifests.

    buildah manifest annotate includes the following options:
    • the --index option to set annotations on the index itself instead of a one of the entries in the image index

    • the --subject option for setting the subject field of an image index.

    buildah manifest create includes the --annotation option for adding annotations to the new image index.

  • podman manifest add Includes a new --artifact option to add Open Container Initiative artifacts to a manifest list.

  • Disable logging Podman health_status events by setting the new healthcheck_events option to false in the containers.conf configuration file under the [engine] section.

  • podman update command of container configuration are persistent. This applies to SQLite and BoltDB database backends.

  • buildah build, podman build, and podman farm build can use the new --compat-volumes option. This option triggers special handling for the contents of directories marked using the VOLUME instruction such that their contents can subsequently only be modified by ADD and COPY instructions. Any changes made in those locations by RUN Instructions are discarded. Previously, this behavior was the default, but is now disabled by default.

  • The system connections and farm information stored in the containers.conf file is now read-only. The system connections and farm information are now be stored in the podman.connections.json file, managed only by Podman. Podman continues to work with the old configuration options such as [engine.service_destinations] and the [farms] section. You manually add and edit connections or farms, however, you can't delete a connection from the containers.conf file with podman system connection remove. System connections that were added by Podman v4.0 remain unchanged after the upgrade to Podman v5.0.

  • podman pod inspect provides a JSON array regardless of the number of pods. Previously, the podman pod inspect omitted the JSON array when inspecting a single pod.

  • podman inspect The output for containers has changed and includes the following:
    • Entrypoint field changes from a string to an array of strings.

    • StopSignal changes from an integer to a string.

    • Returns nil for health checks when inspecting containers without health checks.

  • Cgroups v1 is deprecated. Podman now prints warnings when used on cgroups v1 systems. You can set the PODMAN_IGNORE_CGROUPSV1_WARNING environment variable to suppress warnings.

  • pasta replaces slirp4netns for improved performance as the default tool for rootless networking. Networks named pasta can no longer be used.

See https://github.com/containers/podman/releases for more information.