This page explains how to configure the kubelet's cgroup driver to match the container runtime cgroup driver for kubeadm clusters. Before you begin You should be familiar with the Kubernetes container runtime requirements. Configuring the container runtime cgroup driver The Container runtimes page explains that the systemd driver is recommended for kubeadm based setups instead of the kubelet's default cgroupfs driver, because kubeadm manages the kubelet as a systemd service.

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.

Note: This section links to third party projects that provide functionality required by Kubernetes. The Kubernetes project authors aren't responsible for these projects, which are listed alphabetically. To add a project to this list, read the content guide before submitting a change. More information. Kubernetes applications usually consist of multiple, separate services, each running in its own container. Developing and debugging these services on a remote Kubernetes cluster can be cumbersome, requiring you to get a shell on a running container in order to run debugging tools.

This page explains how to debug Pods running (or crashing) on a Node. Before you begin Your Pod should already be scheduled and running. If your Pod is not yet running, start with Debugging Pods. For some of the advanced debugging steps you need to know on which Node the Pod is running and have shell access to run commands on that Node. You don't need that access to run the standard debug steps that use kubectl.

Creating Secret objects using resource configuration file.

FEATURE STATE: Kubernetes v1.11 [stable] crictl is a command-line interface for CRI-compatible container runtimes. You can use it to inspect and debug container runtimes and applications on a Kubernetes node. crictl and its source are hosted in the cri-tools repository. Before you begin crictl requires a Linux operating system with a CRI runtime. Installing crictl You can download a compressed archive crictl from the cri-tools release page, for several different architectures.

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.

The Kubernetes model for connecting containers Now that you have a continuously running, replicated application you can expose it on a network. Kubernetes assumes that pods can communicate with other pods, regardless of which host they land on. Kubernetes gives every pod its own cluster-private IP address, so you do not need to explicitly create links between pods or map container ports to host ports. This means that containers within a Pod can all reach each other's ports on localhost, and all pods in a cluster can see each other without NAT.

The Common Expression Language (CEL) is used in the Kubernetes API to declare validation rules, policy rules, and other constraints or conditions. CEL expressions are evaluated directly in the API server, making CEL a convenient alternative to out-of-process mechanisms, such as webhooks, for many extensibility use cases. Your CEL expressions continue to execute so long as the control plane's API server component remains available. Language overview The CEL language has a straightforward syntax that is similar to the expressions in C, C++, Java, JavaScript and Go.