This tutorial provides an introduction to managing applications with StatefulSets. It demonstrates how to create, delete, scale, and update the Pods of StatefulSets. Before you begin Before you begin this tutorial, you should familiarize yourself with the following Kubernetes concepts: Pods Cluster DNS Headless Services PersistentVolumes The kubectl command line tool You need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster.

Production-Grade Container Orchestration

Objectives Scale an existing app manually using kubectl. Scaling an application You can create from the start a Deployment with multiple instances using the --replicas parameter for the kubectl create deployment command. Previously we created a Deployment, and then exposed it publicly via a Service. The Deployment created only one Pod for running our application. When traffic increases, we will need to scale the application to keep up with user demand.

FEATURE STATE: Kubernetes v1.30 [alpha](disabled by default) Kubernetes relies on API data being actively re-written, to support some maintenance activities related to at rest storage. Two prominent examples are the versioned schema of stored resources (that is, the preferred storage schema changing from v1 to v2 for a given resource) and encryption at rest (that is, rewriting stale data based on a change in how the data should be encrypted).

This page shows how a Pod can use environment variables to expose information about itself to containers running in the Pod, using the downward API. You can use environment variables to expose Pod fields, container fields, or both. In Kubernetes, there are two ways to expose Pod and container fields to a running container: Environment variables, as explained in this task Volume files Together, these two ways of exposing Pod and container fields are called the downward API.

This page shows how to configure Pods so that they will be assigned particular Quality of Service (QoS) classes. Kubernetes uses QoS classes to make decisions about evicting Pods when Node resources are exceeded. When Kubernetes creates a Pod it assigns one of these QoS classes to the Pod: Guaranteed Burstable BestEffort 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 you how to configure a Pod to use a PersistentVolumeClaim for storage. Here is a summary of the process: You, as cluster administrator, create a PersistentVolume backed by physical storage. You do not associate the volume with any Pod. You, now taking the role of a developer / cluster user, create a PersistentVolumeClaim that is automatically bound to a suitable PersistentVolume. You create a Pod that uses the above PersistentVolumeClaim for storage.

This documentation is about investigating and diagnosing kubectl related issues. If you encounter issues accessing kubectl or connecting to your cluster, this document outlines various common scenarios and potential solutions to help identify and address the likely cause. Before you begin You need to have a Kubernetes cluster. You also need to have kubectl installed - see install tools Verify kubectl setup Make sure you have installed and configured kubectl correctly on your local machine.

FEATURE STATE: Kubernetes v1.21 [stable] This page shows how to limit the number of concurrent disruptions that your application experiences, allowing for higher availability while permitting the cluster administrator to manage the clusters nodes. Before you begin Your Kubernetes server must be at or later than version v1.21. To check the version, enter kubectl version. You are the owner of an application running on a Kubernetes cluster that requires high availability.

Debugging common containerized application issues.