Kubeadm operator

Enhancement Description

• One-line enhancement description (can be used as a release note): Kubeadm operator
• Kubernetes Enhancement Proposal:

https://github.com/kubernetes/enhancements/tree/master/keps/sig-cluster-lifecycle/kubeadm/2505-Kubeadm-operator

Summary

Kubeadm operator would like to enable declarative control of kubeadm workflows, automating the execution and the
orchestration of such tasks across existing nodes in a cluster.

Motivation

Kubeadm binary can execute operations only on the machine where it is running e.g. it is not possible to execute
operations on other nodes, to copy files across nodes, etc.

As a consequence, most of the kubeadm workflows, like kubeadm upgrade,
consists of a complex sequence of tasks that should be manually executed and orchestrated across all the existing nodes
in the cluster.

Such a user experience is not ideal due to the error-prone nature of humans running commands. The manual approach
can be considered a blocker for implementing more complex workflows such as rotating certificate authorities,
modifying the settings of an existing cluster or any task that requires coordination of more than one Kubernetes node.

This KEP aims to address such problems by applying the operator pattern to kubeadm workflows.

• Discussion Link:
• Primary contact (assignee): @fabriziopandini
• Responsible SIGs: sig-cluster-lifecycle
• Enhancement target (which target equals to which milestone):
  • Alpha release target (x.y): TODO
  • Beta release target (x.y): TODO
  • Stable release target (x.y): TODO
• Alpha
  • KEP (k/enhancements) update PR(s):
  • Code (k/k) update PR(s):
  • Docs (k/website) update PR(s):

Please keep this description up to date. This will help the Enhancement Team to track the evolution of the enhancement efficiently.

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/lifecycle stale

[neolit123]

/remove-lifecycle stale

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/lifecycle stale

[neolit123]

/remove-lifecycle stale

[pacoxu]

Any plan for this feature

[neolit123]

We haven't dropped the idea. It would support useful features like cluster wide upgrades and cert rotations. Similarly to other area of kubeadm. Someone has to have the time to work on it. If someone starts work on it again i would like for us to discuss trimming down the heavy boilerplate that kube builder adds.

[fabriziopandini]

I have a prototype and many ideas around this and the kubeadm, library...