Building Kubernetes Minikube

Building Kubernetes Minikube

Kubernetes Minikube binaries are available and the instructions provided below specify the steps to install the version 1.32.0 on Linux on IBM Z.

General Notes:

• When following the steps below please use a standard permission user unless otherwise specified.

• A directory /<source_root>/ will be referred to in these instructions, this is a temporary writable directory anywhere you'd like to place it.

  • Instructions to install Docker can be found here
    • Docker needs to be configured correctly with systemd for minikube to successfully start.
    • Information on configuring the docker systemd unit files to map to the binaries can be found here

Step 1: Install Dependencies

• RHEL (7.8, 7.9, 8.6, 8.8, 8.9)

  sudo yum install -y wget curl git make

• RHEL (9.0, 9.2, 9.3)

  sudo yum install -y --allowerasing wget curl git make

• SLES (12 SP5, 15 SP5)

  sudo zypper install -y wget curl git make

• Ubuntu (20.04, 22.04, 23.10)

  sudo apt-get update
  sudo apt-get install -y wget curl git make

Step 2: Install Minikube and Kubectl

cd $SOURCE_ROOT
export KUBERNETES_VERSION=v1.23.16
curl -LO https://github.com/kubernetes/minikube/releases/download/v1.32.0/minikube-linux-s390x && sudo install minikube-linux-s390x /usr/bin/minikube && rm -rf minikube-linux-s390x
curl -LO https://storage.googleapis.com/kubernetes-release/release/$KUBERNETES_VERSION/bin/linux/s390x/kubectl && chmod +x kubectl && sudo cp kubectl /usr/bin/ && rm -rf kubectl

Step 3: Start Minikube

sudo usermod -aG docker $USER && newgrp docker
minikube start --driver=docker --kubernetes-version=$KUBERNETES_VERSION

Note:

If minikube fails to start with the following:

Unfortunately, an error has occurred:
                timed out waiting for the condition

        This error is likely caused by:
                - The kubelet is not running
                - The kubelet is unhealthy due to a misconfiguration of the node in some way (required cgroups disabled)

This is due to an SELinux permission issue, which can be temporarily disabled to start minikube then re-enabled via:

sudo setenforce 0
minikube start --driver=docker --kubernetes-version=$KUBERNETES_VERSION

Note:

Above command will start a single kubernetes cluster. The cluster can be viewed using the following command:

kubectl get pods --all-namespaces

Output should look similar to this:

NAMESPACE     NAME                               READY   STATUS    RESTARTS   AGE
kube-system   coredns-bd6b6df9f-qwfmk            1/1     Running   0          12s
kube-system   etcd-minikube                      1/1     Running   0          25s
kube-system   kube-apiserver-minikube            1/1     Running   0          27s
kube-system   kube-controller-manager-minikube   1/1     Running   0          24s
kube-system   kube-proxy-9pw8f                   1/1     Running   0          12s
kube-system   kube-scheduler-minikube            1/1     Running   0          24s
kube-system   storage-provisioner                1/1     Running   0          24s

For additional insight into your cluster state, minikube bundles the Kubernetes Dashboard, allowing you to get easily acclimated to your new environment:

minikube dashboard --url=true &

If accessing the dashboard remotely, a local proxy server needs to be started:

kubectl proxy --address='0.0.0.0' --disable-filter=true &

The dashboard can then be accessed via http://<host_ip>:8001/api/v1/namespaces/kubernetes-dashboard/services/http:kubernetes-dashboard:/proxy/.

Step 4: Sample application deployment (optional)

4.1) Install buildx tool (Only for SLES 12 SP5)

cd $SOURCE_ROOT
wget https://github.com/docker/buildx/releases/download/v0.10.2/buildx-v0.10.2.linux-s390x
mkdir -p ~/.docker/cli-plugins
cp buildx-v0.10.2.linux-s390x ~/.docker/cli-plugins/docker-buildx
chmod a+x ~/.docker/cli-plugins/docker-buildx

4.2) Build echoserver image

cd $SOURCE_ROOT
git clone --depth 1 --single-branch --branch v1.24.0 https://github.com/kubernetes/kubernetes.git
cd kubernetes/test/images/
make all WHAT=echoserver
docker tag k8s.gcr.io/e2e-test-images/echoserver:2.5-linux-s390x echoserver:2.5
minikube image load echoserver:2.5

4.3) Create a sample deployment

kubectl create deployment hello-minikube --image=echoserver:2.5
kubectl expose deployment hello-minikube --type=NodePort --port=8080

It may take a moment, but your deployment will soon show up when you run:

kubectl get services hello-minikube

4.4) LoadBalancer deployments

To access a LoadBalancer deployment, use the minikube tunnel command. Here is an example deployment:

kubectl create deployment balanced --image=echoserver:2.5
kubectl expose deployment balanced --type=LoadBalancer --port=8080

In another window, start the tunnel to create a routable IP for the ‘balanced’ deployment:

minikube tunnel

To access this service, run the following command:

kubectl get services balanced

References

• Minikube GitHub Repo
• Minikube Documentation