kubeadm:tldr:e8ac9

The command "kubeadm upgrade apply ${version}" is used to upgrade a Kubernetes cluster to a specific version using the "kubeadm" tool.

Here's a breakdown of the command:

• "kubeadm" is a command-line utility that provides various functionalities for managing a Kubernetes cluster.
• "upgrade" is a subcommand of "kubeadm" used for upgrading a Kubernetes cluster to a new version.
• "apply" is an option of the "upgrade" command, which applies the upgrade to the cluster.
• "${version}" is a placeholder representing the specific version of Kubernetes you want to upgrade to. You need to replace "${version}" with the desired version number or the appropriate version identifier.

When you execute this command, "kubeadm" will perform the necessary actions to upgrade the cluster to the specified version. This may include updating the control plane components, such as the API server, controller manager, and scheduler, as well as making changes to the configuration of the cluster to align with the new version.

It's important to note that this command is typically executed on the control plane node (master node) of the Kubernetes cluster and requires administrative privileges to perform the upgrade. Additionally, it's recommended to take proper backup and conduct thorough testing before upgrading a production cluster to ensure a smooth transition.