Manage security and best-practices with policies.

In a Kubernetes cluster, a node can be shutdown in a planned graceful way or unexpectedly because of reasons such as a power outage or something else external. A node shutdown could lead to workload failure if the node is not drained before the shutdown. A node shutdown can be either graceful or non-graceful. Graceful node shutdown FEATURE STATE: Kubernetes v1.21 [beta] The kubelet attempts to detect node system shutdown and terminates pods running on the node.

In Kubernetes, scheduling refers to making sure that Pods are matched to Nodes so that the kubelet can run them. Preemption is the process of terminating Pods with lower Priority so that Pods with higher Priority can schedule on Nodes. Eviction is the process of proactively terminating one or more Pods on resource-starved Nodes.

Removed feature PodSecurityPolicy was deprecated in Kubernetes v1.21, and removed from Kubernetes in v1.25. Instead of using PodSecurityPolicy, you can enforce similar restrictions on Pods using either or both: Pod Security Admission a 3rd party admission plugin, that you deploy and configure yourself For a migration guide, see Migrate from PodSecurityPolicy to the Built-In PodSecurity Admission Controller. For more information on the removal of this API, see PodSecurityPolicy Deprecation: Past, Present, and Future.

Baseline checklist for ensuring security in Kubernetes clusters.

When several users or teams share a cluster with a fixed number of nodes, there is a concern that one team could use more than its fair share of resources. Resource quotas are a tool for administrators to address this concern. A resource quota, defined by a ResourceQuota object, provides constraints that limit aggregate resource consumption per namespace. It can limit the quantity of objects that can be created in a namespace by type, as well as the total amount of compute resources that may be consumed by resources in that namespace.

This page describes the maximum number of volumes that can be attached to a Node for various cloud providers. Cloud providers like Google, Amazon, and Microsoft typically have a limit on how many volumes can be attached to a Node. It is important for Kubernetes to respect those limits. Otherwise, Pods scheduled on a Node could get stuck waiting for volumes to attach. Kubernetes default limits The Kubernetes scheduler has default limits on the number of volumes that can be attached to a Node:

Perform common configuration tasks for Pods and containers.

FEATURE STATE: Kubernetes v1.30 [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:

When using client certificate authentication, you can generate certificates manually through easyrsa, openssl or cfssl. easyrsa easyrsa can manually generate certificates for your cluster. Download, unpack, and initialize the patched version of easyrsa3. curl -LO https://dl.k8s.io/easy-rsa/easy-rsa.tar.gz tar xzf easy-rsa.tar.gz cd easy-rsa-master/easyrsa3 ./easyrsa init-pki Generate a new certificate authority (CA). --batch sets automatic mode; --req-cn specifies the Common Name (CN) for the CA's new root certificate. ./easyrsa --batch "--req-cn=${MASTER_IP}@`date +%s`" build-ca nopass Generate server certificate and key.