Working with pre-release version...

Lets check the kubeadm version:

`kubeadm version`

kubeadm version: &version.Info{Major:"1", Minor:"19+", GitVersion:"v1.19.0-beta.2.517+ec36ff40016e1e", GitCommit:"ec36ff40016e1ea612ae364b3b550cd31dd04651", GitTreeState:"clean", BuildDate:"2020-07-06T23:48:41Z", GoVersion:"go1.14.4", Compiler:"gc", Platform:"linux/amd64"}

So I'm running on the edge with unreleased code... with beta + some change.

`kubelet --version`

Kubernetes v1.19.0-beta.2.517+ec36ff40016e1e

Have you noticed some inconsistency in the API? :)

This code sux so much... I love and hate kubernetes at the same time.

`kubeadm init`

W0708 00:36:10.404244  268603 configset.go:293] WARNING: kubeadm cannot validate component configs for API groups [kubelet.config.k8s.io kubeproxy.config.k8s.io]
[init] Using Kubernetes version: v1.18.5
[preflight] Running pre-flight checks
error execution phase preflight: [preflight] Some fatal errors occurred:
    [ERROR KubeletVersion]: the kubelet version is higher than the control plane version. This is not a supported version skew and may lead to a malfunctional cluster. Kubelet version: "1.19.0-beta.2.517+ec36ff40016e1e" Control plane version: "1.18.5"
[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

And again some strange thing. K8s is newer but using an older API version. I guess this is because it is not yet released.

It is only a warning. But let's try adding an arg:
`kubeadm init --kubernetes-version=v1.19.0-beta.2.517+ec36ff40016e1e`

Yeah... it works. But warning is still there.

Let's try the other way round:

`vim /etc/systemd/system/kubelet.service` - add --kubernetes-version=v1.18.5 to the call.

`systemctl daemon-reload` to reload the .service files (and possibly other crap).

`service kubelet status` to see if it started.

`kubeadm init --kubernetes-version=v1.18.5` to see if it worked... nope. So I'm back to the version that worked.