kubernetes-sigs/cluster-api

Setting `md.spec.paused` to `true` should fully pause the MachineDeployment

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#8,629 opened on May 10, 2023

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Description

What steps did you take and what happened?

  • Create a legacy cluster with 1 MD
  • Set .spec.paused of the MD to true
  • Edit the MD to change md.spec.replicas

The MachineDeployment scales and creates new Machines.

What did you expect to happen?

Pausing the MachineDeployment should fully pause its reconciliation.

Looking at the MachineDeployment reconciler code the following is the piece of code responsible for this behavior. We still sync the MD even if the MD is paused.

/internal/controllers/machinedeployment/machinedeployment_controller.go#L266-L268

	if md.Spec.Paused {
		return ctrl.Result{}, r.sync(ctx, md, msList)
	}

Additional notes:

  • Setting md.spec.paused to true will not create a new MS but will still reconcile changes that do no need a rollout.
  • Setting the cluster.x-k8s.io/paused annotation will pause the MD completely.

It is better to have consistent behavior and and fully pause MD reconciliation if md.spec.paused is set to true.

Cluster API version

main

Kubernetes version

No response

Anything else you would like to add?

No response

Label(s) to be applied

/kind bug One or more /area label. See https://github.com/kubernetes-sigs/cluster-api/labels?q=area for the list of labels.

Contributor guide

Research direction
Inspect the sync function in machinedeployment controller.go and understand how the paused state is handled. Focus on the condition `if md.Spec.Paused { return ctrl.Result{}, r.sync(ctx, md, msList) }` and ensure that when paused, no reconciliation should occur.
Tech stack
go
Domain
backend
Issue type
Bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
2
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
Half day
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
Active
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
Clear
Prerequisites
GoKubernetes
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
60