Hello, and welcome to today's video presentation on installing Podman, Buildah, and Skopeo
on Oracle Linux 8.
In this video, we provide a background on each of these tools and show how to install
them for working with images and containers.
So let us get started.
Podman, Buildah, and Skopeo are independent tools that you can use to create, run, and
manage applications across compatible Oracle Linux systems by using Open Container Initiative
(OCI) compatible containers.
Podman provides a lightweight utility to run and manage those containers and can re-use
existing container images designed for Kubernetes, Oracle Container Runtime for Docker, and Oracle
Linux Cloud Native Environment.
Unlike Oracle Container Runtime for Docker, Podman does not require a running daemon to
function and enables containers to start and run without root permissions.
For compatibility, Podman helps by running containers correctly on systems using either
the Red Hat Compatible Kernel (RHCK) or the UEK release.
Additional compatibility exists as Podman provides a command-line interface (CLI) intended
as a drop-in replacement for Docker.
Due to this design, most users can alias Docker to Podman (alias docker=podman) without any
problems.
To share applications in a software-as-a-service (SaaS) cloud, Podman integrates with Docker
Hub and Oracle Container Registry.
This integration provides access to existing images and applications.
Besides using existing images, users can create new ones using Buildah.
Buildah is a utility for creating Open Container Initiative (OCI) compatible container images
and provides a broader range of customization options than the more generic podman build
command.
When creating the container images using Buildah, users do not need a running daemon for the
utility to function, and it does not cache builds by default.
This design allows users to run the build infrastructure fully independent from the
container runtime.
In line with a complete build infrastructure, Buildah can push container images to container
registries, making it well-suited for use with deployment scripts and automated build
pipelines.
Lastly, we have Skopeo.
Skopeo is a utility for managing container images on remote container registries, thus
making it possible to inspect a container image's contents without first downloading
it.
Other uses for Skopeo when hosting images in your container registry, include moving
container images from one location to another seamlessly and for bulk-deleting unneeded
container images.
Now that we know a bit about these three tools, let us get them installed.
In this exercise, we use a fully patched Oracle Linux 8 instance on Oracle Cloud Infrastructure.
Open a terminal.
Install Podman by typing sudo dnf install podman.
The dnf command will display the podman package and any dependencies.
When prompted, type y to proceed with the installation.
Once installed, display information about the Podman configuration and version by typing
podman info.
Note that we ran the podman info command as a regular user, and did not require elevated
privileges.
For more podman commands, see the podman manual page.
If you are more familiar with Docker, then you can optionally install the podman-docker
package, which effectively aliases the docker command to podman.
Complete the package installation by typing sudo dnf install podman-docker -y.
The -y option will automatically accept the installation of the package and any listed
dependencies.
With Podman now installed on the system, we can focus on the other utilities.
As mentioned during the introduction, Buildah and Skopeo work independently from Podman.
Therefore, it is possible to install the buildah package on the same system as Podman, or an
alternate system to keep the build infrastructure separated from the running containers.
In this example, we will use the same system for simplicity.
Install the buildah package by typing sudo dnf install buildah.
As before, the dnf command will display the package requested and any dependencies.
After review, type y to proceed with the installation.
Once the command completes, test the install by typing buildah --version.
The output displays the version of the buildah executable installed and confirms it is within
the user's path.
For additional options, type buildah -h or use the buildah manual page.
Lastly, install the skopeo package by typing sudo dnf install skopeo -y.
The package and any dependencies install.
Next, test the package by typing skopeo -h.
The output displays the skopeo command help details.
For more information, see the skopeo manual page.
That completes the install of the Podman, Buildah, and Skopeo tools.
Thank you for watching this video and enjoy using Oracle Linux 8.
Please check our additional information on Oracle Linux 8 in the Oracle Linux 8 Documentation
or Oracle Linux Learning Library.