SeedImage reference

A SeedImage resource allows to build an installation media that can be used to install Elemental onto a node. It requires a baseImage, i.e., a URL to an Elemental installation ISO or node container image, and a registrationRef reference to a MachineRegistration resource, from which the registration part of the Elemental configuration is extracted and injected in the media to produce the final seed image. It is also possible to inject customizations in the cloud-config field.

Once the seed image is ready, the download URL is shared in the .status.downloadURL field. It stays available for download for cleanupAfterMinutes minutes (default is 60, 1 hour), after which it is deleted. Setting retriggerBuild to true retriggers the seed image build process while setting cleanupAfterMinutes to 0 keeps the seed image around till the SeedImage resource is deleted.

The SeedImage resource also has a type field which can be set to either iso, to build an ISO, or raw to build a raw disk image. Raw disk images can be copied directly to the target drive and on first boot will automatically boot into a recovery partition to expand the drive to use the available disk space and register the node, after which it will reboot the same way as for the ISO installation.

If no BuildContainer is specified for the seed-image it will be automatically filled in based on default values and type.

Building a SeedImage for a different platform is accomplished using the targetPlatform field. The platform is specified using os/arch, for example (linux/amd64 or linux/arm64). By default the image will be built for the same platform that the operator is hosted on.

seed images may fill up local storage

The seed images are kept on the node's local storage: pay attention to the number of SeedImage resources you start concurrently and to the ones you may leave around with the auto-cleanup feature disabled (cleanupAfterMinutes = 0) as you may exhaust the storage on your cluster nodes.

The SeedImage resource tracks the seed image build process through two status conditions:

• Ready: tracks the creation of all the required child resources that perform the actual build process.
• SeedImageReady: tracks the status of the build process in the child resources.

Example

apiVersion: elemental.cattle.io/v1beta1
kind: SeedImage
metadata:
  name: ...
  namespace: ...
spec:
  type: ...
  baseImage: ...
  targetPlatform: ...
  buildContainer:
    name: ...
    image: ...
    command: [...]
    args: [...]
    imagePullPolicy: ...
  cloud-config: ...
  registrationRef:
    name: ...
    namespace: ...
  cleanupAfterMinutes: ...
  retriggerBuild: ...