This page explains how to add versioning information to CustomResourceDefinitions, to indicate the stability level of your CustomResourceDefinitions or advance your API to a new version with conversion between API representations. It also describes how to upgrade an object from one version to another. 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...| Kubernetes
The aggregation layer allows Kubernetes to be extended with additional APIs, beyond what is offered by the core Kubernetes APIs. The additional APIs can either be ready-made solutions such as a metrics server, or APIs that you develop yourself. The aggregation layer is different from Custom Resource Definitions, which are a way to make the kube-apiserver recognise new kinds of object. Aggregation layer The aggregation layer runs in-process with the kube-apiserver.| Kubernetes
This page contains an overview of the client libraries for using the Kubernetes API from various programming languages. To write applications using the Kubernetes REST API, you do not need to implement the API calls and request/response types yourself. You can use a client library for the programming language you are using. Client libraries often handle common tasks such as authentication for you. Most client libraries can discover and use the Kubernetes Service Account to authenticate if the...| Kubernetes
Kubernetes provides a command line tool for communicating with a Kubernetes cluster's control plane, using the Kubernetes API. This tool is named kubectl. For configuration, kubectl looks for a file named config in the $HOME/.kube directory. You can specify other kubeconfig files by setting the KUBECONFIG environment variable or by setting the --kubeconfig flag. This overview covers kubectl syntax, describes the command operations, and provides common examples. For details about each command,...| Kubernetes
Each object in your cluster has a Name that is unique for that type of resource. Every Kubernetes object also has a UID that is unique across your whole cluster. For example, you can only have one Pod named myapp-1234 within the same namespace, but you can have one Pod and one Deployment that are each named myapp-1234. For non-unique user-provided attributes, Kubernetes provides labels and annotations. Names A client-provided string that refers to an object in a resource URL, such as /api/v1/...| Kubernetes
This page shows how to install a custom resource into the Kubernetes API by creating a CustomResourceDefinition. 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 playgro...| Kubernetes
In addition to compiled-in admission plugins, admission plugins can be developed as extensions and run as webhooks configured at runtime. This page describes how to build, configure, use, and monitor admission webhooks. What are admission webhooks? Admission webhooks are HTTP callbacks that receive admission requests and do something with them. You can define two types of admission webhooks, validating admission webhook and mutating admission webhook. Mutating admission webhooks are invoked f...| Kubernetes
Kubernetes objects are persistent entities in the Kubernetes system. Kubernetes uses these entities to represent the state of your cluster. Learn about the Kubernetes object model and how to work with these objects.| Kubernetes
The Kubernetes API lets you query and manipulate the state of objects in Kubernetes. The core of Kubernetes' control plane is the API server and the HTTP API that it exposes. Users, the different parts of your cluster, and external components all communicate with one another through the API server.| Kubernetes
Use kubectl patch to update Kubernetes API objects in place. Do a strategic merge patch or a JSON merge patch.| Kubernetes
This page provides an overview of admission controllers. An admission controller is a piece of code that intercepts requests to the Kubernetes API server prior to persistence of the resource, but after the request is authenticated and authorized. Several important features of Kubernetes require an admission controller to be enabled in order to properly support the feature. As a result, a Kubernetes API server that is not properly configured with the right set of admission controllers is an in...| Kubernetes
Operators are software extensions to Kubernetes that make use of custom resources to manage applications and their components. Operators follow Kubernetes principles, notably the control loop. Motivation The operator pattern aims to capture the key aim of a human operator who is managing a service or set of services. Human operators who look after specific applications and services have deep knowledge of how the system ought to behave, how to deploy it, and how to react if there are problems.| Kubernetes
A Secret is an object that contains a small amount of sensitive data such as a password, a token, or a key. Such information might otherwise be put in a Pod specification or in a container image. Using a Secret means that you don't need to include confidential data in your application code. Because Secrets can be created independently of the Pods that use them, there is less risk of the Secret (and its data) being exposed during the workflow of creating, viewing, and editing Pods.| Kubernetes