Buildah, Skopeo and Podman

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Cloud/ Container
| Container

Buildah, Skopeo and Podman

  • Buildah is a tool for building Open Container Initiative (OCI) container images
  • Skopeo is a command line utility that performs various operations on container images and image repositories.
  • Podman is a tool for managing Pods, Containers, and Container Images

Buildah

The Buildah package provides a command line tool that can be used to:

  • create a working container, either from scratch or using an image as a starting point
  • create an image, either from a working container or via the instructions in a Dockerfile
  • images can be built in either the OCI image format or the traditional upstream docker image format
  • mount a working container’s root filesystem for manipulation
  • unmount a working container’s root filesystem
  • use the updated contents of a container’s root filesystem as a filesystem layer to create a new image
  • delete a working container or an image
  • rename a local container

Skopeo

Skopeo is a command line utility that performs various operations on container images and image repositories.

Skopeo can work with OCI images as well as the original Docker v2 images.

Skopeo works with API V2 registries such as Docker registries, the Atomic registry, private registries, local directories and local OCI-layout directories. Skopeo does not require a daemon to be running to perform these operations which consist of:

  • Copying an image from and to various storage mechanisms. For example you can copy images from one registry to another, without requiring privilege.
  • Inspecting a remote image showing its properties including its layers, without requiring you to pull the image to the host.
  • Deleting an image from an image repository.
  • When required by the repository, skopeo can pass the appropriate credentials and certificates for authentication

Podman

At a high level, the scope of libpod and Podman is the following:

  • Support multiple image formats including the OCI and Docker image formats.
  • Support for multiple means to download images including trust & image verification.
  • Container image management (managing image layers, overlay filesystems, etc).
  • Full management of container lifecycle.
  • Support for pods to manage groups of containers together.
  • Resource isolation of containers and pods.
  • Support for a Docker-compatible CLI interface through Podman.
  • Integration with CRI-O to share containers and backend code.