kubernetes doc

Containerization & Orchestration/Kubernetes/Commands/3-Commands.md

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+# Kubernetes Command Reference
+
+This guide provides a concise reference for common `kubectl` commands used to manage Kubernetes clusters. Whether you’re managing nodes, namespaces, pods, deployments, or autoscaling, the examples below will help you perform everyday tasks with confidence.
+
+## General Commands
+
+- **List API Resources**  
+  Display all available API resources along with their short names:
+
+  ```bash
+  kubectl api-resources
+  ```
+
+---
+## API Resources & Documentation
+
+- **Get Detailed Documentation for an API Resource**
+
+  ```bash
+  kubectl explain <api-resource-name>
+  ```
+
+  *Example:*
+
+  ```bash
+  kubectl explain pod
+  ```
+
+  ```bash
+  kubectl explain pod.metadata
+  ```
+
+
+---
+
+## Applying YAML Files
+
+- **Apply a Configuration from a YAML File**
+
+  Apply a YAML configuration to a specific namespace:
+
+  ```bash
+  kubectl apply -f <yaml-file> -n <namespace-name>
+  ```
+
+---
+
+## Viewing Cluster Resources
+
+- **Display All Resources in a Namespace**
+
+  ```bash
+  kubectl get all -n <namespace-name>
+  ```
+
+- **Display ReplicaSets, Pods, and Deployments in a Specific Namespace**
+
+  ```bash
+  kubectl get rs,pods,deployments -n <namespace-name>
+  ```
+
+---
+
+## ReplicaSet & Deployment Management
+
+### Scaling and Rollouts
+
+- **Scale a ReplicaSet**
+
+  ```bash
+  kubectl scale rs <replicaset-name> --replicas=<count> -n <namespace-name>
+  ```
+
+- **View Rollout History of a Deployment**
+
+  ```bash
+  kubectl rollout history deployment <deployment-name> -n <namespace-name>
+  ```
+
+- **View Details of a Specific Revision**
+
+  ```bash
+  kubectl rollout history deployment <deployment-name> -n <namespace-name> --revision=<number>
+  ```
+
+- **Roll Back a Deployment to a Specific Revision**
+
+  ```bash
+  kubectl rollout undo deployment <deployment-name> -n <namespace-name> --to-revision=<number>
+  ```
+
+### Autoscaling
+
+- **Autoscale a Deployment**  
+  Automatically scale a deployment based on CPU utilization:
+
+  ```bash
+  kubectl autoscale deployment <deployment-name> -n <namespace-name> --cpu-percent=<target-cpu-percentage> --min=<min-pods> --max=<max-pods>
+  ```
+
+- **View Horizontal Pod Autoscalers (HPA)**
+
+  ```bash
+  kubectl get hpa -n <namespace-name>
+  ```
+
+---
+
+## Port Forwarding
+
+Sometimes you need to access a service or pod directly from your local machine. Use the following command to forward a port:
+
+```bash
+kubectl port-forward -n <namespace-name> svc/<service-name> <local-port>:<target-port>
+```
+
+> **Example:** Forward local port 8080 to port 80 of the service named `my-service` in the `mynamespace` namespace:
+>
+> ```bash
+> kubectl port-forward -n mynamespace svc/my-service 8080:80
+> ```
+
+---
+
+## Additional Information
+
+- **Static Manifest Files**  
+  Any YAML files placed in `/etc/kubernetes/manifests/` are automatically loaded when the kubelet starts (for example, after a server reboot).
+
+