kubeadm init

Hi @chrispokorni,
Sorry to comment on this old thread but seeing same issue while trying to run a command:
kubeadm init --config=kubeadm-config.yaml --upload-certs | tee kubeadm-init.out

****result is an error, like below:****

_root@cp:~# kubeadm init --config=kubeadm-config.yaml --upload-certs | tee kubeadm-init.out
could not interpret GroupVersionKind; unmarshal error: error converting YAML to JSON: yaml: line 4: could not find expected ':'
To see the stack trace of this error execute with --v=5 or higher
root@cp:~# _

The kubeadm-config.yaml contents is below and I see same while comparing to the PDF that is in the course.

Could you please point me what is wrong with this content that the command is complaining about?

Thanks,
Gaurav

Hi @gaurav4978,

As you can see, YAML syntax for Kubernetes follows very strict rules for spacing, indentation, and it is case sensitive.

The line numbers, expected space after ':', the missing 2 spaces before 'podSubnet', they all collectively caused YAML to JSON conversion error message.

These errors are common when the content is extracted from the PDF lab guide via copy/paste. In order to prevent these types of issues, you have a SOLUTIONS tarball that you may have downloaded in an earlier step, which includes config files, scripts, and definition files needed for labs. I would recommend navigating through the content of the SOLUTIONS subdirectory to familiarize yourself and find desired artifacts.

The short command to init the control-plane works as a last resort, but it does not initialize the cluster in a manner consistent with the exercises in the lab guide, and you will get to see different results for some steps, while others may not work as intended. This is why the kubeadm-config.yaml file was provided, to customize the cluster's bootstrapping process.

Regards,
-Chris

Hi @gaurav4978,

If you compare closely the YAML content provided earlier with the content from the PDF, you will see there are differences critical to the expected format of the kubeadm-config.yaml file.

If you read carefully the Overview section of Lab Exercise 3.1, you will find instructions on how to download the tarball and how to extract it.

Regards,
-Chris

Hi there,

Hi all,

I'm facing a similar problem and can't seem to get past it. Here's how my file looks like:
root...~# cat kubeadm-config.yaml
apiVersion: kubeadm.k8s.io/v1beta3
kind: ClusterConfiguration
kubernetesVersion: 1.24.1
controlPlaneEndpoint: "k8scp:6443"
networking:
podSubnet: 192.168.0.0/16

root...~# kubeadm init --config=kubeadm-config.yaml --upload-certs | tee kubeadm-init.out
[init] Using Kubernetes version: v1.24.1
[preflight] Running pre-flight checks
[WARNING SystemVerification]: missing optional cgroups: blkio
error execution phase preflight: [preflight] Some fatal errors occurred:
[ERROR CRI]: container runtime is not running: output: time="2023-03-05T02:28:30Z" level=fatal msg="validate service connection: CRI v1 runtime API is not implemented for endpoint \"unix:///var/run/containerd/containerd.sock\": rpc error: code = Unimplemented desc = unknown service runtime.v1.RuntimeService"
, error: exit status 1
[preflight] If you know what you are doing, you can make a check non-fatal with --ignore-preflight-errors=...
To see the stack trace of this error execute with --v=5 or higher

Thanks for any tips

One small addition from me as I encountered the same issue during the course.
I had the same error with example below:

---
apiVersion: kubeadm.k8s.io/v1beta4
kind: ClusterConfiguration
kubernetesVersion: 1.34
controlPlaneEndpoint: k8scp:6443
networking:
  podSubnet: 192.168.0.0/16

And the issue was that kubernetesVersion shouldn't be a number and was treated as one. Need to put it inside quotes or add .0 there.
Working version:

---
apiVersion: kubeadm.k8s.io/v1beta4
kind: ClusterConfiguration
kubernetesVersion: 1.34.0
controlPlaneEndpoint: k8scp:6443
networking:
  podSubnet: 192.168.0.0/16