This page describes the CoreDNS upgrade process and how to install CoreDNS instead of kube-dns. 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 v1.18 [stable] This page shows how to configure Group Managed Service Accounts (GMSA) for Pods and containers that will run on Windows nodes. Group Managed Service Accounts are a specific type of Active Directory account that provides automatic password management, simplified service principal name (SPN) management, and the ability to delegate the management to other administrators across multiple servers. In Kubernetes, GMSA credential specs are configured at a Kubernetes cluster-wide scope as Custom Resources.

FEATURE STATE: Kubernetes v1.34 [stable](enabled by default) This page shows you how to allocate devices to your Pods by using dynamic resource allocation (DRA). These instructions are for workload operators. Before reading this page, familiarize yourself with how DRA works and with DRA terminology like ResourceClaims and ResourceClaimTemplates. For more information, see Dynamic Resource Allocation (DRA). About device allocation with DRA As a workload operator, you can claim devices for your workloads by creating ResourceClaims or ResourceClaimTemplates.

Many applications rely on configuration which is used during either application initialization or runtime. Most times, there is a requirement to adjust values assigned to configuration parameters. ConfigMaps are a Kubernetes mechanism that let you inject configuration data into application pods. The ConfigMap concept allow you to decouple configuration artifacts from image content to keep containerized applications portable. For example, you can download and run the same container image to spin up containers for the purposes of local development, system test, or running a live end-user workload.

This example demonstrates how to limit the amount of storage consumed in a namespace. The following resources are used in the demonstration: ResourceQuota, LimitRange, and PersistentVolumeClaim. 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.

Kubernetes can be configured to use swap memory on a node, allowing the kernel to free up physical memory by swapping out pages to backing storage. This is useful for multiple use-cases. For example, nodes running workloads that can benefit from using swap, such as those that have large memory footprints but only access a portion of that memory at any given time. It also helps prevent Pods from being terminated during memory pressure spikes, shields nodes from system-level memory spikes that might compromise its stability, allows for more flexible memory management on the node, and much more.

Production-Grade Container Orchestration

This guide is to help users debug applications that are deployed into Kubernetes and not behaving correctly. This is not a guide for people who want to debug their cluster. For that you should check out this guide. Diagnosing the problem The first step in troubleshooting is triage. What is the problem? Is it your Pods, your Replication Controller or your Service? Debugging Pods Debugging Replication Controllers Debugging Services Debugging Pods The first step in debugging a Pod is taking a look at it.

Kubernetes offers two distinct ways for clients that run within your cluster, or that otherwise have a relationship to your cluster's control plane to authenticate to the API server. A service account provides an identity for processes that run in a Pod, and maps to a ServiceAccount object. When you authenticate to the API server, you identify yourself as a particular user. Kubernetes recognises the concept of a user, however, Kubernetes itself does not have a User API.

This page shows how to run a replicated stateful application using a StatefulSet. This application is a replicated MySQL database. The example topology has a single primary server and multiple replicas, using asynchronous row-based replication. Note:This is not a production configuration. MySQL settings remain on insecure defaults to keep the focus on general patterns for running stateful applications in Kubernetes. Before you begin You need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster.