📖 Adding MicroK8s providers

[ktsakalozos]

What this PR does / why we need it:
This PR adds the MicroK8s bootstrap and control plane providers to the list of default providers to enable with clusterctl init and also updates the providers list in the Book.

The MicroK8s team is committing to support and develop these two providers.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

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[killianmuldoon]

/ok-to-test

Thanks for adding microK8s to the provider list! Hoping to try it out soon

[killianmuldoon]

Looking good - just a couple of nits

[killianmuldoon]

We should also add a Control plane section here to cover the micro K8s control plane provider 🙂

[ktsakalozos]

Do you want me to add it in this PR or on a separate one?

We should put there:

kubeadm
microk8s
nested
talos

[killianmuldoon]

We can do it in this PR if it's okay for you - otherwise a follow up is fine. Just seems like the list is starting to get long enough to add here, and I've seen a lot of movement in the community on control plane providers.

[ktsakalozos]

Added a Control Plane section with the respective providers mentioned in alphabetical order.

[sbueringer]

Thx!

[ktsakalozos]

/retest

[ktsakalozos]

Thank you for the very fast review @killianmuldoon everything seems to be in the right place now

[killianmuldoon]

>  ./bin/clusterctl init -b microk8s -i docker -c microk8s
Fetching providers
Installing cert-manager Version="v1.9.1"
Waiting for cert-manager to be available...
Installing Provider="cluster-api" Version="v1.2.1" TargetNamespace="capi-system"
Installing Provider="bootstrap-microk8s" Version="v0.1.0" TargetNamespace="capm-system"
Installing Provider="control-plane-microk8s" Version="v0.1.0" TargetNamespace="capm-system"
Installing Provider="infrastructure-docker" Version="v1.2.1" TargetNamespace="capd-system"

Your management cluster has been initialized successfully!

Awesome!

/lgtm

[killianmuldoon]

For a follow up - it would be great to add microk8s and CAPM everywhere else we talk about providers. Are you using the same abbreviation CAPM for both providers here? I see they're in the same namespace. (All of this for curiosity only and completely non-blocking for this PR)

[sbueringer]

For a follow up - it would be great to add microk8s and CAPM everywhere else we talk about providers. Are you using the same abbreviation CAPM for both providers here? I see they're in the same namespace. (All of this for curiosity only and completely non-blocking for this PR)

Agree. Shouldn't be relevant for this PR, but I wonder if you'll run into problems at some point. In general providers have a unique abbreviation. They are also deployed into namespaces which are inferred from the abbreviation. E.g.

• CABPK => capi-kubeadm-bootstrap-system
• KCP => capi-kubeadm-control-plane-system
• CAPI => capi-system
• CAPA => capa-system

We have a list of providers under provider-contract.md. We should probably also include the new providers there.

I don't really know 100% if you will run into problems when using the same abbreviation for both and when deploying them into the same namespace.

@fabriziopandini probably knows more about the limitations / contracts

[fabriziopandini]

/lgtm
/approve

Abbreviations are meant for users to identify providers, so if we have two providers IMO there should be two abbreviations; also by convention we have bootstrap providers starting with CABP, controlplane providers ending with CP.

As far as I remember we don't use those abbreviations heavily in the application - they are meant for humans - but we use them in the tilt file and probably in E2E as well. Given that AFAIK there are no two providers with the same label, I would say this is not supported.

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[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: fabriziopandini

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[ktsakalozos]

Thank you for the super-fast review and the advice.

We will followup with your suggestions, the abbreviation and discussion updates with MicroK8s.