_Topology Aware Routing_ provides a mechanism to help keep network traffic within the zone where it originated. Preferring same-zone traffic between Pods in your cluster can help with reliability, performance (network latency and throughput), or cost.

The kubectl command-line tool supports several different ways to create and manage Kubernetes objects. This document provides an overview of the different approaches. Read the Kubectl book for details of managing objects by Kubectl. Management techniques Warning:A Kubernetes object should be managed using only one technique. Mixing and matching techniques for the same object results in undefined behavior. Management technique Operates on Recommended environment Supported writers Learning curve Imperative commands Live objects Development projects 1+ Lowest Imperative object configuration Individual files Production projects 1 Moderate Declarative object configuration Directories of files Production projects 1+ Highest Imperative commands When using imperative commands, a user operates directly on live objects in a cluster.

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 covers how to customize the components that kubeadm deploys. For control plane components you can use flags in the ClusterConfiguration structure or patches per-node. For the kubelet and kube-proxy you can use KubeletConfiguration and KubeProxyConfiguration, accordingly. All of these options are possible via the kubeadm configuration API. For more details on each field in the configuration you can navigate to our API reference pages. Note:Customizing the CoreDNS deployment of kubeadm is currently not supported.

There are many methods and tools for setting up your own production Kubernetes cluster. For example: kubeadm kops: An automated cluster provisioning tool. For tutorials, best practices, configuration options and information on reaching out to the community, please check the kOps website for details. kubespray: A composition of Ansible playbooks, inventory, provisioning tools, and domain knowledge for generic OS/Kubernetes clusters configuration management tasks. You can reach out to the community on Slack channel #kubespray.

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.

FEATURE STATE: Kubernetes v1.28 [alpha] Kubernetes 1.30 includes an alpha feature that lets an API Server proxy a resource requests to other peer API servers. This is useful when there are multiple API servers running different versions of Kubernetes in one cluster (for example, during a long-lived rollout to a new release of Kubernetes). This enables cluster administrators to configure highly available clusters that can be upgraded more safely, by directing resource requests (made during the upgrade) to the correct kube-apiserver.

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.

Synopsis Set the selector on a resource. Note that the new selector will overwrite the old selector if the resource had one prior to the invocation of 'set selector'. A selector must begin with a letter or number, and may contain letters, numbers, hyphens, dots, and underscores, up to 63 characters. If --resource-version is specified, then updates will use this resource version, otherwise the existing resource-version will be used. Note: currently selectors can only be set on Service objects.

Synopsis Update the user, group, or service account in a role binding or cluster role binding. kubectl set subject (-f FILENAME | TYPE NAME) [--user=username] [--group=groupname] [--serviceaccount=namespace:serviceaccountname] [--dry-run=server|client|none] Examples # Update a cluster role binding for serviceaccount1 kubectl set subject clusterrolebinding admin --serviceaccount=namespace:serviceaccount1 # Update a role binding for user1, user2, and group1 kubectl set subject rolebinding admin --user=user1 --user=user2 --group=group1 # Print the result (in YAML format) of updating rolebinding subjects from a local, without hitting the server kubectl create rolebinding admin --role=admin --user=admin -o yaml --dry-run=client | kubectl set subject --local -f - --user=foo -o yaml Options --all Select all resources, in the namespace of the specified resource types