The status of a node in Kubernetes is a critical aspect of managing a Kubernetes cluster. In this article, we'll cover the basics of monitoring and maintaining node status to ensure a healthy and stable cluster. Node status fields A Node's status contains the following information: Addresses Conditions Capacity and Allocatable Info Declared Features You can use kubectl to view a Node's status and other details: kubectl describe node <insert-node-name-here> Each section of the output is described below.

Kubernetes nodes can be scheduled to Capacity. Pods can consume all the available capacity on a node by default. This is an issue because nodes typically run quite a few system daemons that power the OS and Kubernetes itself. Unless resources are set aside for these system daemons, pods and system daemons compete for resources and lead to resource starvation issues on the node. The kubelet exposes a feature named 'Node Allocatable' that helps to reserve compute resources for system daemons.

This page provides an overview of the steps you should follow to upgrade a Kubernetes cluster. The Kubernetes project recommends upgrading to the latest patch releases promptly, and to ensure that you are running a supported minor release of Kubernetes. Following this recommendation helps you to stay secure. The way that you upgrade a cluster depends on how you initially deployed it and on any subsequent changes. At a high level, the steps you perform are:

This page shows how to use a projected Volume to mount several existing volume sources into the same directory. Currently, secret, configMap, downwardAPI, and serviceAccountToken volumes can be projected. Note:serviceAccountToken is not a volume type. 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 v1.24 [stable] This page shows how to use a SOCKS5 proxy to access the API of a remote Kubernetes cluster. This is useful when the cluster you want to access does not expose its API directly on the public internet. 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.

Configuring the aggregation layer allows the Kubernetes apiserver to be extended with additional APIs, which are not part of the core Kubernetes APIs. 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:

Note This tutorial applies only for new clusters. Pod Security is an admission controller that carries out checks against the Kubernetes Pod Security Standards when new pods are created. It is a feature GA'ed in v1.25. This tutorial shows you how to enforce the baseline Pod Security Standard at the cluster level which applies a standard configuration to all namespaces in a cluster. To apply Pod Security Standards to specific namespaces, refer to Apply Pod Security Standards at the namespace level.

FEATURE STATE: Kubernetes v1.35 [stable](enabled by default) This page explains how to change the CPU and memory resource requests and limits assigned to a container without recreating the Pod. Traditionally, changing a Pod's resource requirements necessitated deleting the existing Pod and creating a replacement, often managed by a workload controller. In-place Pod Resize allows changing the CPU/memory allocation of container(s) within a running Pod while potentially avoiding application disruption. The process for resizing Pod resources is covered in Resize CPU and Memory Resources assigned to Pods.

FEATURE STATE: Kubernetes v1.18 [stable] This page shows how to use the runAsUserName setting for Pods and containers that will run on Windows nodes. This is roughly equivalent of the Linux-specific runAsUser setting, allowing you to run applications in a container as a different username than the default. 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 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.