This page provides an overview of controlling access to the Kubernetes API. Users access the Kubernetes API using kubectl, client libraries, or by making REST requests. Both human users and Kubernetes service accounts can be authorized for API access. When a request reaches the API, it goes through several stages, illustrated in the following diagram: Transport security By default, the Kubernetes API server listens on port 6443 on the first non-localhost network interface, protected by TLS.

This task outlines the steps needed to update your container runtime to containerd from Docker. It is applicable for cluster operators running Kubernetes 1.23 or earlier. This also covers an example scenario for migrating from dockershim to containerd. Alternative container runtimes can be picked from this page. Before you begin 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.

Dynamic volume provisioning allows storage volumes to be created on-demand. Without dynamic provisioning, cluster administrators have to manually make calls to their cloud or storage provider to create new storage volumes, and then create PersistentVolume objects to represent them in Kubernetes. The dynamic provisioning feature eliminates the need for cluster administrators to pre-provision storage. Instead, it automatically provisions storage when users create PersistentVolumeClaim objects. Background The implementation of dynamic volume provisioning is based on the API object StorageClass from the API group storage.

In Kubernetes, a VolumeSnapshot represents a snapshot of a volume on a storage system. This document assumes that you are already familiar with Kubernetes persistent volumes. Introduction Similar to how API resources PersistentVolume and PersistentVolumeClaim are used to provision volumes for users and administrators, VolumeSnapshotContent and VolumeSnapshot API resources are provided to create volume snapshots for users and administrators. A VolumeSnapshotContent is a snapshot taken from a volume in the cluster that has been provisioned by an administrator.

This document highlights and consolidates configuration best practices that are introduced throughout the user guide, Getting Started documentation, and examples. This is a living document. If you think of something that is not on this list but might be useful to others, please don't hesitate to file an issue or submit a PR. General Configuration Tips When defining configurations, specify the latest stable API version. Configuration files should be stored in version control before being pushed to the cluster.

Kubernetes supports running nodes on either Linux or Windows. You can mix both kinds of node within a single cluster. This page provides an overview to networking specific to the Windows operating system. Container networking on Windows Networking for Windows containers is exposed through CNI plugins. Windows containers function similarly to virtual machines in regards to networking. Each container has a virtual network adapter (vNIC) which is connected to a Hyper-V virtual switch (vSwitch).

When you specify a Pod, you can optionally specify how much of each resource a container needs. The most common resources to specify are CPU and memory (RAM); there are others. When you specify the resource request for containers in a Pod, the kube-scheduler uses this information to decide which node to place the Pod on. When you specify a resource limit for a container, the kubelet enforces those limits so that the running container is not allowed to use more of that resource than the limit you set.

FEATURE STATE: Kubernetes v1.14 [stable] Pods can have priority. Priority indicates the importance of a Pod relative to other Pods. If a Pod cannot be scheduled, the scheduler tries to preempt (evict) lower priority Pods to make scheduling of the pending Pod possible. Warning:In a cluster where not all users are trusted, a malicious user could create Pods at the highest possible priorities, causing other Pods to be evicted/not get scheduled.

This document describes the concept of a StorageClass in Kubernetes. Familiarity with volumes and persistent volumes is suggested. A StorageClass provides a way for administrators to describe the classes of storage they offer. Different classes might map to quality-of-service levels, or to backup policies, or to arbitrary policies determined by the cluster administrators. Kubernetes itself is unopinionated about what classes represent. The Kubernetes concept of a storage class is similar to “profiles” in some other storage system designs.

This page shows how to configure a Pod to use a Volume for storage. A Container's file system lives only as long as the Container does. So when a Container terminates and restarts, filesystem changes are lost. For more consistent storage that is independent of the Container, you can use a Volume. This is especially important for stateful applications, such as key-value stores (such as Redis) and databases. Before you begin You need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster.