Kubernetes Resource Types

This repository provides hands-on for working with Kubernetes' built-in resource types, catering to diverse application deployment and operational needs.

Overview

Each directory corresponds to a specific Kubernetes resource type and includes a Taskfile that outlines the commands required to create, interact with, and clean up the resource.
Examples are deployed into unique namespaces to avoid naming conflicts and simplify cleanup, as deleting a namespace removes all associated resources.

How to Use

1. Navigate to the directory for the resource type you want to explore.
2. Use the Taskfile to follow the step-by-step process:
   • Create a namespace for the resources:

     task 01-create-namespace
     

   • Run the other tasks in sequence to create and manage resources.
   • Finally, delete the namespace to clean up:

     task 07-delete-namespace
     

Included Resource Types

The following Kubernetes resource types are covered in this repository:

• Namespace: Organize cluster resources by dividing them between multiple users.
• Pod: The smallest deployable unit, representing one or more containers running in the cluster.
• ReplicaSet: Maintains a desired number of pod replicas to ensure application availability.
• Deployment: Manages stateless applications with features like rolling updates and rollbacks.
• Service: Defines a policy for accessing a group of pods as a single logical entity.
• Job: Runs one or more pods until a task is completed.
• CronJob: Schedules jobs to execute at specific times or intervals.
• DaemonSet: Ensures that specific pods are running on all or selected nodes in the cluster.
• StatefulSet: Manages stateful applications with guarantees around pod identity and ordering.
• ConfigMap: Stores non-sensitive configuration data for consumption by pods.
• Secret: Stores sensitive data like credentials, tokens, or keys securely.
• Ingress: Manages external HTTP/HTTPS access to services within the cluster.
• GatewayAPI: Handles advanced traffic routing and control within the cluster.
• PersistentVolume (PV) and PersistentVolumeClaim (PVC): Provides persistent storage for pods.
• RBAC (Role-Based Access Control): Configures permissions and access control within the cluster.

How to Set Up and Use Devbox

Install Devbox

Devbox is a CLI tool that helps you create and manage isolated development environments.
To install Devbox, run the following command:

curl -fsSL https://get.jetify.com/devbox | bash

Alternatively, you can use Homebrew:

brew install jetpack-io/devbox/devbox

For more installation options, visit the Devbox documentation.

Start a Devbox Shell

Once devbox is installed and the devbox.json file is present in the project root, you can start a Devbox shell:

devbox shell

This command loads the development environment with all the packages and tools specified in devbox.json.

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Examples of Useful Commands

Once inside the Devbox shell, you can run commands for the tools included in your devbox.json. Here are some examples:

kubectl Commands

• View all pods in a namespace:

  kubectl get pods -n <namespace>

• Apply a configuration file:

  kubectl apply -f <file.yaml>

• Delete a resource (e.g., a pod):

  kubectl delete pod <pod-name> -n <namespace>

• Describe a resource:

  kubectl describe <resource-type> <resource-name> -n <namespace>

kubectx Commands

• Switch between Kubernetes clusters:

  kubectx <cluster-name>

• List all available contexts:

  kubectx

kind

• Create a local Kubernetes cluster:

  kind create cluster --name <cluster-name>

• Delete a Kind cluster:

  kind delete cluster --name <cluster-name>

Out of Scope

The following resource types are not covered in detail but may be explored later:

• LimitRange: Sets constraints on resource usage within a namespace.
• NetworkPolicy: Controls network traffic flow at the IP/port level.
• MutatingWebhookConfiguration: Configures webhooks for modifying API server requests.
• ValidatingWebhookConfiguration: Sets webhooks for validating API server requests.
• HorizontalPodAutoscaler: Automatically adjusts pod counts based on metrics like CPU usage.
• CustomResourceDefinition (CRD): Allows the creation of custom resource types in Kubernetes.

Notes

• Follow the order of resource types as outlined in this README for a structured learning experience.
• Each example aligns with best practices, making it easier to understand and apply in real-world scenarios.

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Explore and experiment with these Kubernetes resource types to deepen your understanding of managing workloads and configurations in Kubernetes!