An issue that comes up rather frequently for new installations of Kubernetes is that a Service is not working properly. You've run your Pods through a Deployment (or other workload controller) and created a Service, but you get no response when you try to access it. This document will hopefully help you to figure out what's going wrong. Running commands in a Pod For many steps here you will want to see what a Pod running in the cluster sees.

FEATURE STATE: Kubernetes v1.31 [stable] This page shows how to assign extended resources to a Container. 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:

This page shows how to view, work in, and delete namespaces. The page also shows how to use Kubernetes namespaces to subdivide your cluster. Before you begin Have an existing Kubernetes cluster. You have a basic understanding of Kubernetes Pods, Services, and Deployments. Viewing namespaces List the current namespaces in a cluster using: kubectl get namespaces NAME STATUS AGE default Active 11d kube-node-lease Active 11d kube-public Active 11d kube-system Active 11d Kubernetes starts with four initial namespaces:

Perform common configuration tasks for Pods and containers.

This page shows how to attach handlers to Container lifecycle events. Kubernetes supports the postStart and preStop events. Kubernetes sends the postStart event immediately after a Container is started, and it sends the preStop event immediately before the Container is terminated. A Container may specify one handler per event. Before you begin You need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster.

This page shows how to investigate problems related to the execution of Init Containers. The example command lines below refer to the Pod as <pod-name> and the Init Containers as <init-container-1> and <init-container-2>. 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.

FEATURE STATE: Kubernetes v1.30 [beta] (enabled by default: false) This page shows how to configure a user namespace for pods. This allows you to isolate the user running inside the container from the one in the host. A process running as root in a container can run as a different (non-root) user in the host; in other words, the process has full privileges for operations inside the user namespace, but is unprivileged for operations outside the namespace.

Kubernetes provides a built-in admission controller to enforce the Pod Security Standards. You can configure this admission controller to set cluster-wide defaults and exemptions. Before you begin Following an alpha release in Kubernetes v1.22, Pod Security Admission became available by default in Kubernetes v1.23, as a beta. From version 1.25 onwards, Pod Security Admission is generally available. To check the version, enter kubectl version. If you are not running Kubernetes 1.

Synopsis Update the labels on a resource. A label key and value must begin with a letter or number, and may contain letters, numbers, hyphens, dots, and underscores, up to 63 characters each. Optionally, the key can begin with a DNS subdomain prefix and a single '/', like example.com/my-app. If --overwrite is true, then existing labels can be overwritten, otherwise attempting to overwrite a label will result in an error.

Synopsis Update the taints on one or more nodes. A taint consists of a key, value, and effect. As an argument here, it is expressed as key=value:effect. The key must begin with a letter or number, and may contain letters, numbers, hyphens, dots, and underscores, up to 253 characters. Optionally, the key can begin with a DNS subdomain prefix and a single '/', like example.com/my-app. The value is optional. If given, it must begin with a letter or number, and may contain letters, numbers, hyphens, dots, and underscores, up to 63 characters.