Production-Grade Container Orchestration

Synopsis Create a pod disruption budget with the specified name, selector, and desired minimum available pods. kubectl create poddisruptionbudget NAME --selector=SELECTOR --min-available=N [--dry-run=server|client|none] Examples # Create a pod disruption budget named my-pdb that will select all pods with the app=rails label # and require at least one of them being available at any point in time kubectl create poddisruptionbudget my-pdb --selector=app=rails --min-available=1 # Create a pod disruption budget named my-pdb that will select all pods with the app=nginx label # and require at least half of the pods selected to be available at any point in time kubectl create pdb my-pdb --selector=app=nginx --min-available=50% Options --allow-missing-template-keys     Default: true If true, ignore any errors in templates when a field or map key is missing in the template.

Synopsis Create a service using a specified subcommand. kubectl create service [flags] Options -h, --help help for service Parent Options Inherited --as string Username to impersonate for the operation. User could be a regular user or a service account in a namespace. --as-group strings Group to impersonate for the operation, this flag can be repeated to specify multiple groups. --as-uid string UID to impersonate for the operation. --cache-dir string     Default: "

Synopsis Display merged kubeconfig settings or a specified kubeconfig file. You can use --output jsonpath={...} to extract specific values using a jsonpath expression. kubectl config view [flags] Examples # Show merged kubeconfig settings kubectl config view # Show merged kubeconfig settings, raw certificate data, and exposed secrets kubectl config view --raw # Get the password for the e2e user kubectl config view -o jsonpath='{.users[?(@.name == "e2e")].user.password}' Options --allow-missing-template-keys     Default: true If true, ignore any errors in templates when a field or map key is missing in the template.

Resource Types Event EventList Policy PolicyList Event Appears in: EventList Event captures all the information that can be included in an API audit log. FieldDescription apiVersionstringaudit.k8s.io/v1 kindstringEvent level [Required] Level AuditLevel at which event was generated auditID [Required] k8s.io/apimachinery/pkg/types.UID Unique audit ID, generated for each request. stage [Required] Stage Stage of the request handling when this event instance was generated. requestURI [Required] string RequestURI is the request URI as sent by the client to a server.

Production-Grade Container Orchestration

Synopsis The Kubernetes controller manager is a daemon that embeds the core control loops shipped with Kubernetes. In applications of robotics and automation, a control loop is a non-terminating loop that regulates the state of the system. In Kubernetes, a controller is a control loop that watches the shared state of the cluster through the apiserver and makes changes attempting to move the current state towards the desired state. Examples of controllers that ship with Kubernetes today are the replication controller, endpoints controller, namespace controller, and serviceaccounts controller.

The EndpointSlice API is the mechanism that Kubernetes uses to let your Service scale to handle large numbers of backends, and allows the cluster to update its list of healthy backends efficiently.

FEATURE STATE: Kubernetes v1.30 [stable] Pods were considered ready for scheduling once created. Kubernetes scheduler does its due diligence to find nodes to place all pending Pods. However, in a real-world case, some Pods may stay in a "miss-essential-resources" state for a long period. These Pods actually churn the scheduler (and downstream integrators like Cluster AutoScaler) in an unnecessary manner. By specifying/removing a Pod's .spec.schedulingGates, you can control when a Pod is ready to be considered for scheduling.

To scale an application and provide a reliable service, you need to understand how the application behaves when it is deployed. You can examine application performance in a Kubernetes cluster by examining the containers, pods, services, and the characteristics of the overall cluster. Kubernetes provides detailed information about an application's resource usage at each of these levels. This information allows you to evaluate your application's performance and where bottlenecks can be removed to improve overall performance.