Autoscaling

[luisdavim]

Hi, is it possible to integrate the cluster autoscaler with the machine-controller? Or does the controller provide the autoscaling features?

[alvaroaleman]

Hey, thanks for inquiring. What we need is a cluster-autoscaler implementation that supports clusterapi v1alpha1 as backend. @frobware has built one already, althought it isn't merged: kubernetes/autoscaler#1866

Other than that, we'd need to fix #564 (althought that doesn't matter if you run on a platform that does have a cloudprovider)

[luisdavim]

thanks @alvaroaleman

[kubermatic-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.

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/lifecycle stale

[luisdavim]

/remove-lifecycle 

[alvaroaleman]

/remove-lifecycle stale

[kubermatic-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.

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/lifecycle stale

[kron4eg]

/remove-lifecycle stale

[kron4eg]

So, upstream clusterAPI change got merged and released. And machine-controller doesn't need to do anything!

In order to make autoscaling work, MachineDeployments or MachineSets should be annotated like this:

apiVersion: cluster.k8s.io/v1alpha1
kind: MachineDeployment
metadata:
  annotations:
    cluster.k8s.io/cluster-api-autoscaler-node-group-min-size: "1"
    cluster.k8s.io/cluster-api-autoscaler-node-group-max-size: "10"

But such annotations are out of machine-controller scope and should be provided by the user.
See more info at kubernetes/autoscaler#1866

[madalinignisca]

May I ask how the autoscaler annotation could be used in the output.tf kubeone_workers?

From the examples there is a "$var.cluster_name}-pool1" example.

[kron4eg]

Terraform output is unmarshalled onto

https://github.com/kubermatic/kubeone/blob/8418d9d6c14e38a525618829fc1c36d56a8c3f0a/pkg/apis/kubeone/v1beta2/types.go#L418-L425

so there is annotations field that will be copied to MachineDeployment.ObjectMeta.Annotations

https://github.com/kubermatic/kubeone/blob/8418d9d6c14e38a525618829fc1c36d56a8c3f0a/pkg/apis/kubeone/v1beta2/types.go#L432

so the resulted terraform output would look something like this:

output "kubeone_workers" {
  value = {
    "${var.cluster_name}-pool1" = {
      replicas = var.workers_replicas
      providerSpec = {
        annotations = {
          "cluster.k8s.io/cluster-api-autoscaler-node-group-min-size" = "1"
          "cluster.k8s.io/cluster-api-autoscaler-node-group-max-size" = "10"          
        }
...

[madalinignisca]

@kron4eg Thank you so much mate!