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🛠️ Minikube With Podman on Apple Silicon

Aug 29, 2022
4 min read

Minikube has been a go-to environment for running a single-node cluster to test out the Kubernetes features on a local platform. For macOS computers with an Apple Silicon, a.k.a. M1 or M2, minikube provides an ARM64 version and can be installed with Homebrew.

However when it comes to start minikube after successfully installed it, it would require Docker as the default driver. Here comes my problem. As a matter of fact, Docker on macOS has long been released under the name of “Docker Desktop”, which contains a huge pile of Electron based applications and UI. It starts slow too. I don’t ever want to install such a monstrous thing in my system. So I have to give up the default driver and look for alternatives.

At the time of writing, minikube supports various kinds of drivers, such as Docker, Hyperkit, Hyper-V, KVM, Parallels, Podman, VirtualBox, and VMware Fusion/Workstation. After an hour of struggling and testing, Podman stood out. It’s backed by a QEMU virtual machine, supports Docker API and Docker-based tools, and can be intsalled in a very smooth fasion.

So I’m going to record the steps to initialize and maintain a minikube cluster with Podman.

Installation

With the help of the Get Started documentation for minikube, just pick an installation option that works. Mine was brew install minikube.

Then the Podman installation done with brew install podman.

Simple enough.

Start Up

Create a Podman machine with the following command, giving it 2 CPU cores and 8Gi memory.

podman machine init --cpus 2 --memory 8192 --disk-size 80
podman machine start
podman system connection default podman-machine-default-root

Now Podman should be running in the background. One can check out the information with podman info command, or find out its running stats with podman stats command.

To start minikube, follow the step below. By default, minikube uses Docker as the driver. One should pass a --driver argument to change that.

minikube start --driver=podman --container-runtime=cri-o

One should see the output similar to the following logs:

❯ minikube start --driver=podman --container-runtime=cri-o

😄  minikube v1.26.1 on Darwin 12.5.1 (arm64)
✨  Using the podman (experimental) driver based on existing profile
👍  Starting control plane node minikube in cluster minikube
🚜  Pulling base image ...
E0829 11:34:04.822031   11181 cache.go:203] Error downloading kic artifacts:  not yet implemented, see issue #8426
🔄  Restarting existing podman container for "minikube" ...
🎁  Preparing Kubernetes v1.24.3 on CRI-O 1.24.1 ...
E0829 11:34:09.704438   11181 start.go:129] Unable to get host IP: RoutableHostIPFromInside is currently only implemented for linux
🔗  Configuring CNI (Container Networking Interface) ...
🔎  Verifying Kubernetes components...
    ▪ Using image gcr.io/k8s-minikube/storage-provisioner:v5
    ▪ Using image kubernetesui/dashboard:v2.6.0
    ▪ Using image kubernetesui/metrics-scraper:v1.0.8
🌟  Enabled addons: storage-provisioner, default-storageclass, dashboard
🏄  Done! kubectl is now configured to use "minikube" cluster and "default" namespace by default

Alternative to explicitly passing the --driver argument, one can change the defautl driver with this command:

minikube config set driver podman

Stop / Restart

To stop the minikube + Podman system, follow these commands:

minikube stop
podman machine stop

To restart the system, simply run start respectively (note the sequence, podman should go first as minikube depends on it):

podman machine start
minikube start --driver=podman --container-runtime=cri-o
# or with the default driver changed to podman:
minikube start

Anything Else?

Q: If there are multiple clusters to manage, including but not limited to GKE (by Google Cloud) and EKS (by AWS) etc., how to manage and switch from these clusters?

A: This can be configured through ~/.kube/config easily as Kubernetes has the concept of “Context”, which basically means different clusters. Upon minikube successfully starting, a new context called minikube shall be inserted automatically to this config file. One can list and switch to a certain context using the following commands (switching to minikube for example):

kubectl config get-contexts
kubectl config set current-context minikube

Q: How to test out a named StorageClass in a PVC object with minikube?

A: By default, minikube comes with a built-in SC named standard. It provides dynamic storage provisioning when one creates a PVC with non-named storage class. One should create a storage class with the customized name before creating the PVC with a named storage class to enable auto-creation of PV and PVC. First, create the named SC like this:

apiVersion: storage.k8s.io/v1
kind: StorageClass
metadata:
  name: your-custom-name
  annotations:
    storageclass.kubernetes.io/is-default-class: "false"
provisioner: k8s.io/minikube-hostpath

It’s important to set the provisioner field to k8s.io/minikube-hostpath, otherwise no auto-creation would happen. After the SC has been successfully created, when applying the following PVC object, one should observe that a PV being automatically created and the PVC gets instantly fulfilled:

kind: PersistentVolumeClaim
apiVersion: v1
metadata:
  name: {{ .Name }}
  namespace: {{ .Namespace }}
spec:
  accessModes: [ "ReadWriteOnce" ]
  storageClassName: your-custom-name
  volumeMode: Filesystem
  resources:
    requests:
      storage: {{ .DiskSize }}

You’ll find this article helpful with understanding dynamic provisioning of persistent storage with minikube.

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