Kubernetes Beginners Commands

Kubernetes Concepts:

• Pod: The smallest deployable unit in Kubernetes. A pod can contain one or more containers.
• Node: A physical or virtual machine in the cluster where pods are scheduled.
• Deployment: A higher-level resource for managing pods. It provides updates and scaling capabilities.
• Service: An abstraction to access a set of pods. There are different types, including ClusterIP, NodePort, and LoadBalancer.
• Namespace: A way to partition resources in a cluster. Useful for multi-tenancy.
• ReplicaSet: Ensures a specified number of pod replicas are running at all times.

Kubernetes Commands:

• kubectl get pods: List all pods in the current namespace.
• kubectl get nodes: List all nodes in the cluster.
• kubectl get deployments: List all deployments.
• kubectl get services: List all services.
• kubectl get namespaces: List all namespaces.
• kubectl describe pod <pod-name>: Get detailed information about a pod.
• kubectl logs <pod-name>: Show logs for a specific pod.
• kubectl exec -it <pod-name> -- /bin/sh: Start an interactive shell in a pod.
• kubectl apply -f <filename>: Create or update resources from a YAML file.
• kubectl delete pod <pod-name>: Delete a pod.
• kubectl scale deployment <deployment-name> --replicas=<replica-count>: Scale the number of replicas in a deployment.

Pod Management:

• kubectl create -f <filename>: Create a pod from a YAML file.
• kubectl expose pod <pod-name> --type=NodePort --port=80: Expose a pod as a service on a specific port.
• kubectl label pods <pod-name> <label-key>=<label-value>: Add labels to pods for easier management.
• kubectl run <pod-name> --image=<image-name>: Create a pod with a specified container image.
• kubectl delete pod <pod-name>: Delete a pod.

Configuration:

• kubectl config view: View the current Kubernetes configuration.
• kubectl config use-context <context-name>: Switch to a different context (cluster).
• kubectl config set-context <context-name> --namespace=<namespace>: Set the default namespace for a context.

Troubleshooting:

• kubectl describe pod <pod-name>: Get detailed information about a pod, including events.
• kubectl logs <pod-name>: Show container logs for a specific pod.
• kubectl exec -it <pod-name> -- /bin/sh: Start an interactive shell in a pod for troubleshooting.