Gardener Extension for Garden Linux OS

This controller operates on the OperatingSystemConfig resource in the extensions.gardener.cloud/v1alpha1 API group.

It manages those objects that are requesting...

• Garden Linux OS configuration (.spec.type=gardenlinux) and its FIPS hardened variant (.spec.type=gardenlinux-fips):

  ---
  apiVersion: extensions.gardener.cloud/v1alpha1
  kind: OperatingSystemConfig
  metadata:
    name: pool-01-original
    namespace: default
  spec:
    type: gardenlinux
    units:
      ...
    files:
      ...

  Please find a concrete example in the example folder.

• MemoryOne on Garden Linux configuration (spec.type=memoryone-gardenlinux):

  ---
  apiVersion: extensions.gardener.cloud/v1alpha1
  kind: OperatingSystemConfig
  metadata:
    name: pool-01-original
    namespace: default
  spec:
    type: memoryone-gardenlinux
    units:
      ...
    files:
      ...
    providerConfig:
      apiVersion: memoryone-gardenlinux.os.extensions.gardener.cloud/v1alpha1
      kind: OperatingSystemConfiguration
      memoryTopology: "2"
      systemMemory: "6x"

  Please find a concrete example in the example folder.

After reconciliation the resulting data will be stored in a secret within the same namespace (as the config itself might contain confidential data). The name of the secret will be written into the resource's .status field:

...
status:
  ...
  cloudConfig:
    secretRef:
      name: osc-result-pool-01-original
      namespace: default
  command: /usr/bin/env bash <path>
  units:
  - kubelet-monitor.service
  - kubelet.service

The secret has one data key cloud_config that stores the generation.

An example for a ControllerRegistration resource that can be used to register this controller to Gardener can be found here.

Please find more information regarding the extensibility concepts and a detailed proposal here.

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How to start using or developing this extension controller locally

You can run the controller locally on your machine by executing make start. Please make sure to have the kubeconfig to the cluster you want to connect to ready in the ./dev/kubeconfig file. Static code checks and tests can be executed by running make verify. We are using Go modules for Golang package dependency management and Ginkgo/Gomega for testing.

Feedback and Support

Feedback and contributions are always welcome!

Please report bugs or suggestions as GitHub issues or reach out on Slack (join the workspace here).

Learn more!

Please find further resources about out project here:

• Our landing page gardener.cloud
• "Gardener, the Kubernetes Botanist" blog on kubernetes.io
• "Gardener Project Update" blog on kubernetes.io
• Gardener Extensions Golang library
• GEP-1 (Gardener Enhancement Proposal) on extensibility
• Extensibility API documentation