🌟 Introduction to Kubernetes

Kubernetes, often abbreviated as K8s, is an open-source platform designed to automate the deployment, scaling, and operation of application containers. It provides a framework to run distributed systems resiliently. This documentation provides a basic introduction and commands to get started with Kubernetes for beginners.

📚 Basic Concepts

1. Pod

• The smallest and simplest Kubernetes object. A pod represents a single instance of a running process in your cluster.

2. Service

• A way to expose an application running on a set of Pods as a network service.

3. Deployment

• Manages a set of identical pods. Used to scale up or down and update pods systematically.

4. Namespace

• A way to divide cluster resources between multiple users.

🛠️ Kubernetes Commands

Cluster Setup

1. Check Cluster Information

   kubectl cluster-info

2. Get Nodes in the Cluster

   kubectl get nodes

Working with Namespaces

1. List All Namespaces

   kubectl get namespaces

2. Create a New Namespace

   kubectl create namespace <namespace-name>

3. Delete a Namespace

   kubectl delete namespace <namespace-name>

Pods

1. List All Pods

   kubectl get pods

2. Get Pod Details

   kubectl describe pod <pod-name>

3. Delete a Pod

   kubectl delete pod <pod-name>

Deployments

1. List All Deployments

   kubectl get deployments

2. Create a Deployment

   kubectl create deployment <deployment-name> --image=<image-name>

3. Scale a Deployment

   kubectl scale deployment <deployment-name> --replicas=<number-of-replicas>

4. Update a Deployment

   kubectl set image deployment/<deployment-name> <container-name>=<new-image>

5. Delete a Deployment

   kubectl delete deployment <deployment-name>

Services

1. List All Services

   kubectl get services

2. Expose a Deployment as a Service

   kubectl expose deployment <deployment-name> --type=<service-type> --port=<port>

3. Delete a Service

   kubectl delete service <service-name>

ConfigMaps and Secrets

1. Create a ConfigMap

   kubectl create configmap <configmap-name> --from-literal=<key>=<value>

2. List ConfigMaps

   kubectl get configmaps

3. Create a Secret

   kubectl create secret generic <secret-name> --from-literal=<key>=<value>

4. List Secrets

   kubectl get secrets

Logs and Debugging

1. View Pod Logs

   kubectl logs <pod-name>

2. Execute Command in Pod

   kubectl exec -it <pod-name> -- <command>

3. Get Events in the Cluster

   kubectl get events