Lab 4.1 step 7: $sudo kubeadm upgrade plan

I faced similar issue - whats the solution ?

kubeadm upgrade plan
[upgrade/config] Making sure the configuration is correct:
[upgrade/config] Reading configuration from the cluster...
[upgrade/config] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml'
[upgrade/config] FATAL: this version of kubeadm only supports deploying clusters with the control plane version >= 1.21.0. Current version: v1.20.11
To see the stack trace of this error execute with --v=5 or higher

Hey , here i have the same problem. i am using vms with ubuntu 20.04 (maybe that's the problem?).anyway there is a way to update the control plane or i have to start from scrach with other linux ? (if is the second, exactly what distribution/version , i need to use to avoid all problems?)

I'm having the same problem. How can I fix this? (LAB 4.1 - Upgrade the Cluster - exercise 8)

ubuntu@ip-172-31-54-32:~$ sudo kubeadm upgrade plan
[preflight] Running pre-flight checks.
[upgrade/config] Reading configuration from the cluster...
[upgrade/config] FYI: You can look at this config file with 'kubectl -n kube-system get cm kubeadm-config -o yaml'
[upgrade/init config] FATAL: this version of kubeadm only supports deploying clusters with the control plane version >= 1.29.0. Current version: v1.27.1
To see the stack trace of this error execute with --v=5 or higher
ubuntu@ip-172-31-54-32:~$ sudo kubeadm version
kubeadm version: &version.Info{Major:"1", Minor:"30", GitVersion:"v1.30.1", GitCommit:"6911225c3f747e1cd9d109c305436d08b668f086", GitTreeState:"clean", BuildDate:"2024-05-14T10:49:05Z", GoVersion:"go1.22.2", Compiler:"gc", Platform:"linux/amd64"}
ubuntu@ip-172-31-54-32:~$ sudo kubectl version
WARNING: This version information is deprecated and will be replaced with the output from kubectl version --short. Use --output=yaml|json to get the full version.
Client Version: version.Info{Major:"1", Minor:"27", GitVersion:"v1.27.1", GitCommit:"4c9411232e10168d7b050c49a1b59f6df9d7ea4b", GitTreeState:"clean", BuildDate:"2023-04-14T13:21:19Z", GoVersion:"go1.20.3", Compiler:"gc", Platform:"linux/amd64"}
Kustomize Version: v5.0.1
The connection to the server localhost:8080 was refused - did you specify the right host or port?
ubuntu@ip-172-31-54-32:~$ sudo kubelet --version
Kubernetes v1.27.1

@chrispokorni, I think I didn't get it. My kubernetes is on v1.27.1, but my kubeadm is on v1.30.1. How will I be able to upgrade my kubernetes to 1.28.1 when the kubeadm "only supports deploying clusters with the control plane version >= 1.29.0". Do I have to downgrade the kubeadm?