Image-based operating systems allow the operating system, configuration, and applications to be versioned, deployed, and updated as a single unit. By using an image-based operating system, you reduce operational risks by minimizing drift between tested and deployed environments.

Image-based operating systems also reduce failed updates through transactional updates and rollbacks, and reduce maintenance and replacement costs. When an OS update fails after reboot, the device automatically rolls back to the previous working version. See Automatic rollback when an OS update fails in the Additional resources section.

The Red Hat Edge Manager focuses on image-based Linux operating systems that run bootable container image (bootc). For more information, see bootc in the Additional resources section.

Note

In disconnected environments, mirror base images and bootc-image-builder to a local registry and stage offline RPM sources before you build. In Dockerfiles and build commands, replace registry.redhat.io references with your mirrored registry path. See Installing Red Hat Edge Manager on Red Hat Enterprise Linux in disconnected environments and Configuring the image builder worker in disconnected environments in the Additional resources section.

Important

The bootc tool does not update package-based operating systems.

Choosing an image building path

You can build operating system images in two ways:

• Simplified image building: A short workflow (a few questions in the Red Hat Edge Manager UI) that uses pre-configured registries. You select a base image, binding mode (Early or Late), and optional disk image formats (ISO, VMDK, QCOW2). The Red Hat Edge Manager agent and required services are included automatically. Build status and logs are visible in the UI. Use this path when you want a ready-to-use image quickly without customizing the build.
• Advanced image building: Full control by using a base bootc image, a Containerfile, podman, bootc-image-builder, and signing. Use this path when you need custom layers, drivers, or manual signing.

Note

The operating system disk image contains partitions, volumes, the file system, and the initial bootc image. You need to create the operating system disk image only once, during provisioning. For subsequent device updates, only the bootc operating system image is required, which contains the files in the file system.

You can also use pre-built or curated bootc images from the Software Catalog in the Flight Control web console, when your administrator has configured catalog endpoints that provide them.

Additionally, you can publish built images to the Software Catalog through image promotion. See Image promotion and catalog publication in the Additional resources section.

See the following image building topics:

• Configuring trusted base images on an OCI repository
• Building images with the simplified workflow
• Publishing an image build to the Software Catalog
• Building a _bootc operating system image for the Red Hat Edge Manager_
• Special considerations for building images
• Building for specific target platforms