This page explains two different approaches to setting up a highly available Kubernetes cluster using kubeadm: With stacked control plane nodes. This approach requires less infrastructure. The etcd members and control plane nodes are co-located. With an external etcd cluster. This approach requires more infrastructure. The control plane nodes and etcd members are separated. Before proceeding, you should carefully consider which approach best meets the needs of your applications and environment.

As with any program, you might run into an error installing or running kubeadm. This page lists some common failure scenarios and have provided steps that can help you understand and fix the problem. If your problem is not listed below, please follow the following steps: If you think your problem is a bug with kubeadm: Go to github.com/kubernetes/kubeadm and search for existing issues. If no issue exists, please open one and follow the issue template.

This page shows how to access clusters using the Kubernetes API. Before you begin You need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. It is recommended to run this tutorial on a cluster with at least two nodes that are not acting as control plane hosts. If you do not already have a cluster, you can create one by using minikube or you can use one of these Kubernetes playgrounds:

FEATURE STATE: Kubernetes v1.32 [stable] (enabled by default: true) The Kubernetes Memory Manager enables the feature of guaranteed memory (and hugepages) allocation for pods in the Guaranteed QoS class. The Memory Manager employs hint generation protocol to yield the most suitable NUMA affinity for a pod. The Memory Manager feeds the central manager (Topology Manager) with these affinity hints. Based on both the hints and Topology Manager policy, the pod is rejected or admitted to the node.

FEATURE STATE: Kubernetes v1.34 [beta] This page provides an overview of MutatingAdmissionPolicies. MutatingAdmissionPolicies allow you change what happens when someone writes a change to the Kubernetes API. If you want to use declarative policies just to prevent a particular kind of change to resources (for example: protecting platform namespaces from deletion), ValidatingAdmissionPolicy is a simpler and more effective alternative. To use the feature, enable the MutatingAdmissionPolicy feature gate (which is off by default) and set --runtime-config=admissionregistration.

A security context defines privilege and access control settings for a Pod or Container. Security context settings include, but are not limited to: Discretionary Access Control: Permission to access an object, like a file, is based on user ID (UID) and group ID (GID). Security Enhanced Linux (SELinux): Objects are assigned security labels. Running as privileged or unprivileged. Linux Capabilities: Give a process some privileges, but not all the privileges of the root user.

Details of the metric data that Kubernetes components export.

kubeadm init phase enables you to invoke atomic steps of the bootstrap process. Hence, you can let kubeadm do some of the work and you can fill in the gaps if you wish to apply customization. kubeadm init phase is consistent with the kubeadm init workflow, and behind the scene both use the same code. kubeadm init phase preflight Using this command you can execute preflight checks on a control-plane node.

Production-Grade Container Orchestration

Synopsis The Kubernetes controller manager is a daemon that embeds the core control loops shipped with Kubernetes. In applications of robotics and automation, a control loop is a non-terminating loop that regulates the state of the system. In Kubernetes, a controller is a control loop that watches the shared state of the cluster through the apiserver and makes changes attempting to move the current state towards the desired state. Examples of controllers that ship with Kubernetes today are the replication controller, endpoints controller, namespace controller, and serviceaccounts controller.