Chapter 1. Introducing RHEL for Edge images
A RHEL for Edge image is an rpm-ostree image that includes system packages to remotely install RHEL on Edge servers.
The system packages include:
- Base OS package
- Podman as the container engine
- Additional RPM content
You can customize the image to configure the OS content as per your requirements, and can deploy them on physical and virtual machines, in an on-premise, cloud, or container environment.
You can deploy a RHEL for Edge image on Bare Metal, Appliance, and Edge servers.
With a RHEL for Edge image, you can achieve the following:
1.1. RHEL for Edge—supported architecture
Currently, you can deploy RHEL for Edge images on AMD and Intel 64-bit systems.
1.2. How to compose and deploy a RHEL for Edge image
The overall process to compose and deploy a RHEL for Edge image varies depending on whether your deployment environment is network-based or non-network-based.
Broadly, composing and deploying a RHEL for Edge image involves the following two phases:
-
Composing a RHEL rpm-ostree image using Image Builder. You can access Image Builder through a command-line interface in the
composer-clitool, or use a graphical user interface in the RHEL web console. - Deploying the image using RHEL installer.
While composing a RHEL for Edge image, you can select any of the following image types:
- RHEL for Edge Commit (.tar)
- Suitable for network-based environments. The commit image type is not directly bootable, even though it contains a full operating system. To boot commit image type, you must deploy it.
- RHEL for Edge Container (.tar)
-
Suitable for non-network-based deployments. The image type creates an
OSTreecommit and embeds it into an OCI container with a web server. When the container is started, the web server serves the commit as an OSTree repository. - RHEL for Edge Installer (.iso)
- Suitable for non-network-based deployments. The image type pulls the commit from the running container and creates an installable boot ISO with a kickstart file configured to use the embedded OSTree commit.
- RHEL for Edge Raw image (.raw.xz)
- Suitable for both non-network-based deployments and network-based deployments.
- RHEL for Edge Simplified Installer (.iso)
- Suitable for both non-network-based deployments and network-based deployments.
The image types vary in terms of their contents, and are therefore suitable for different types of deployment environments.
Additional resources
1.3. Non-network-based deployments
Use Image Builder to create flexible RHEL rpm-ostree images to suit your requirements, and then use Anaconda to deploy them in your environment.
You can access Image Builder through a command-line interface in the composer-cli tool, or use a graphical user interface in the RHEL web console.
Composing and deploying a RHEL for Edge image in non-network-based deployments involves the following high-level steps:
- Install and register a RHEL system
- Install Image Builder
- Using Image Builder, create a blueprint with customizations for RHEL for Edge Container image
- Import the RHEL for Edge blueprint in Image Builder
- Create a RHEL for Edge image embed in an OCI container with a webserver ready to deploy the commit as an OSTree repository
- Download the RHEL for Edge Container image file
- Deploy the container serving a repository with the RHEL for Edge Container commit
- Using Image Builder, create a blueprint for RHEL for Edge Installer image
- Create a RHEL for Edge Installer image configured to pull the commit from the running container embedded with RHEL for Edge Container image
- Download the RHEL for Edge Installer image
- Run the installation
- Create an image
The following diagram represents the RHEL for Edge image non-network deployment workflow:
Figure 1.1. Deploying RHEL for Edge in non-network environment
1.4. Network-based deployments
Use Image Builder to create flexible RHEL rpm-ostree images to suit your requirements, and then use Anaconda to deploy them in your environment. Image Builder automatically identifies the details of your deployment setup and generates the image output as an edge-commit as a .tar file.
You can access Image Builder through a command-line interface in the composer-cli tool, or use a graphical user interface in the RHEL web console.
You can compose and deploy the RHEL for Edge image by performing the following high-level steps:
- Install and register a RHEL system
- Install Image Builder
- Using Image Builder, create a blueprint for RHEL for Edge image
- Import the RHEL for Edge blueprint in Image Builder
- Create a RHEL for Edge image
- Download the RHEL for Edge image file
- Set up a web server
- Download a RHEL boot.iso image
- Using the web server, install the RHEL for Edge image on Edge devices
The following diagram represents the RHEL for Edge network image deployment workflow:
Figure 1.2. Deploying RHEL for Edge in network-base environment
1.5. Difference between RHEL RPM images and RHEL for Edge images
You can create RHEL system images in traditional package-based RPM format and also as RHEL for Edge (rpm-ostree) images.
You can use the traditional package-based RPMs to deploy RHEL on traditional data centers. However, with RHEL for Edge images you can deploy RHEL on servers other than traditional datacenter. These servers include systems where processing of large amounts of data is done closest to the source where data is generated—Edge servers.
Refer to the following table to know how RHEL for Edge images differ from the package-based RHEL RPM images.
Table 1.1. Difference between RHEL RPM images and RHEL for Edge images
| Key attributes | RHEL RPM image | RHEL for Edge image |
| OS assembly | You can assemble the packages locally to form an image. | The packages are assembled in an ostree which you can install on a system. |
| OS updates |
You can use |
You can use |
| Repository | The package contains DNF repositories | The package contains Ostree remote repository |
| User access permissions | Read write |
Read-only ( |
| Data persistence | You can mount the image to any non tmpfs mount point |
|