In a Kubernetes cluster, the components on the worker nodes - kubelet and kube-proxy - need to communicate with Kubernetes control plane components, specifically kube-apiserver. In order to ensure that communication is kept private, not interfered with, and ensure that each component of the cluster is talking to another trusted component, we strongly recommend using client TLS certificates on nodes. The normal process of bootstrapping these components, especially worker nodes that need certificates so they can communicate safely with kube-apiserver, can be a challenging process as it is often outside of the scope of Kubernetes and requires significant additional work.

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 incomplete server that will not support all the features you expect.

Role-based access control (RBAC) is a method of regulating access to computer or network resources based on the roles of individual users within your organization. RBAC authorization uses the rbac.authorization.k8s.io API group to drive authorization decisions, allowing you to dynamically configure policies through the Kubernetes API. To enable RBAC, start the API server with the --authorization-config flag set to a file that includes the RBAC authorizer; for example: apiVersion: apiserver.

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 API client is running inside the Kubernetes cluster, or can understand the kubeconfig file format to read the credentials and the API Server address.

This page shows how to use a Volume to communicate between two Containers running in the same Pod. See also how to allow processes to communicate by sharing process namespace between containers. 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.

Synopsis Create a cluster role. kubectl create clusterrole NAME --verb=verb --resource=resource.group [--resource-name=resourcename] [--dry-run=server|client|none] Examples # Create a cluster role named "pod-reader" that allows user to perform "get", "watch" and "list" on pods kubectl create clusterrole pod-reader --verb=get,list,watch --resource=pods # Create a cluster role named "pod-reader" with ResourceName specified kubectl create clusterrole pod-reader --verb=get --resource=pods --resource-name=readablepod --resource-name=anotherpod # Create a cluster role named "foo" with API Group specified kubectl create clusterrole foo --verb=get,list,watch --resource=rs.

Bootstrap tokens are used for establishing bidirectional trust between a node joining the cluster and a control-plane node, as described in authenticating with bootstrap tokens. kubeadm init creates an initial token with a 24-hour TTL. The following commands allow you to manage such a token and also to create and manage new ones. kubeadm token create Create bootstrap tokens on the server Synopsis This command will create a bootstrap token for you.

Seccomp stands for secure computing mode and has been a feature of the Linux kernel since version 2.6.12. It can be used to sandbox the privileges of a process, restricting the calls it is able to make from userspace into the kernel. Kubernetes lets you automatically apply seccomp profiles loaded onto a node to your Pods and containers. Seccomp fields FEATURE STATE: Kubernetes v1.19 [stable] There are four ways to specify a seccomp profile for a pod:

Synopsis Dump cluster information out suitable for debugging and diagnosing cluster problems. By default, dumps everything to stdout. You can optionally specify a directory with --output-directory. If you specify a directory, Kubernetes will build a set of files in that directory. By default, only dumps things in the current namespace and 'kube-system' namespace, but you can switch to a different namespace with the --namespaces flag, or specify --all-namespaces to dump all namespaces.

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