======kubectl Cheat Sheet======
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=====CLUSTER LIFECYCLE COMMANDS=====
  * **minikube start**
    *Starts a local Kubernetes cluster
    * Automatically configures kubectl to point to the cluster
  * **minikube stop**
    * Stops the cluster without deleting it
  * **minikube delete**
    * Completely deletes the Kubernetes cluster
    * Removes all namespaces, system pods, and workloads
    * This is the correct way to fully reset Kubernetes

=====BASIC CLUSTER VERIFICATION=====
  * **kubectl get nodes**
    * Confirms kubectl can connect to the cluster
    * Verifies node readiness
  * **kubectl get pods**
    * Lists pods in the current namespace
  * **kubectl get pods -A**
    * Lists pods across all namespaces
    * Includes system namespaces like kube-system

=====RESOURCE INSPECTION=====
  * **kubectl describe pod **
    * Shows detailed pod configuration and runtime state
    * Displays events (very important for debugging)
    * First command to use when something is broken

=====WINDOWS CMD SHORTCUT=====
  * **doskey k=kubectl $***
    * Creates a temporary shortcut so "k" can be used instead of "kubectl"
    * Only lasts for the current Command Prompt session
    * Windows CMD does not support Linux-style aliases

=====OUTPUT FORMATTING=====
  * **kubectl get pods**
    * Default, human-readable summary output
  * **kubectl get pods -o wide**
    * Adds pod IP and node name
  * **kubectl get pod -o yaml**
    * Shows the full Kubernetes object definition
    * Useful for learning resource structure
  * **kubectl get pods -o name**
    * Outputs only resource names
    * Useful for scripting
  * **kubectl get pods -o custom-columns=NAME:.metadata.name,PHASE:.status.phase**
    * Displays selected fields in custom columns
  * **kubectl get pods -o jsonpath="{.items[*].metadata.name}"**
    * Extracts specific values from Kubernetes API output
    * Foundation for automation and scripting

=====IMPERATIVE VS DECLARATIVE=====
  * Imperative commands
    * Tell Kubernetes what to do immediately
    * Fast but not repeatable or version-controlled
  * Examples:
    * Creating deployments
    * Scaling replicas directly
  * Declarative workflow
    * Define desired state in YAML
    * Kubernetes reconciles actual state to match
  * Workflow:
    * Export YAML from a resource
    * Edit YAML using Notepad or VS Code
    * Apply YAML with kubectl apply
  * Declarative is preferred in production environments.

=====DEBUGGING PODS AND CONTAINERS=====

Standard debugging flow: \\
1. **kubectl get pods** -> Identify failing or pending pods \\
2. **kubectl describe pod** -> Look at events and status \\
3. **kubectl logs** -> View application logs \\
4. **kubectl logs** --previous -> View logs from a crashed container \\
5. **kubectl exec -it -- sh** -> Access a running container shell \\
6. **kubectl debug -it --image=busybox --target=[PODNAME]** -> Attach an ephemeral debug container \\
Important distinction:
  * Pod name and container name are different
  * Container names are found via describe or JSONPath

=====NAMESPACES AND CONTEXTS=====
  * **kubectl create namespace sandbox**
    * Creates an isolated workspace
  * **kubectl get pods -n sandbox**
    * Lists resources in a specific namespace
  * **kubectl config set-context --current --namespace=sandbox**
    * Sets default namespace for the current context
  * **kubectl config current-context**
    * Shows which cluster/context kubectl is using
  * Namespaces are the safest unit for testing and cleanup.

=====CLEANUP COMMANDS=====
  * **kubectl delete deployment demo**
    * Removes user-created workloads
  * **kubectl delete namespace sandbox**
    * Deletes everything inside that namespace
  * **minikube delete**
    * Fully resets Kubernetes
    * Only supported way to remove kube-system indirectly

=====KUBE-SYSTEM NAMESPACE=====
  * Created automatically by Kubernetes
  * Contains control plane and core system components
  * Cannot and should not be deleted
  * A clean cluster always includes kube-system pods
  * If you want kube-system gone, delete the entire cluster instead.

=====WINDOWS-SPECIFIC NOTES=====
  * Windows CMD does not support alias; use doskey
  * YAML editing is done with external editors (Notepad, VS Code)
  * JSONPath requires double quotes in CMD
  * Many Kubernetes tutorials assume Linux shells and need adjustment

=====COMMON MISTAKES AND GOTCHAS=====
  * Thinking kubectl installs or runs Kubernetes
    * kubectl is only a client
  * Expecting an empty cluster after cleanup
    * System pods in kube-system always exist
  * Trying to delete kube-system
    * This is intentionally forbidden
  * Forgetting namespaces when resources seem missing
    * Default namespace may be empty
  * Confusing pod names with container names
    * Multi-container pods require explicit container targeting
  * Using imperative commands for long-term management
    * Declarative YAML is the production standard
  * Assuming Linux shell commands work on Windows CMD
    * Alias, quoting, and editors differ
  * Editing live resources instead of source YAML
    * kubectl edit is convenient but not Git-friendly

=====MENTAL MODELS=====
  * kube-system = operating system processes
  * Your namespaces = application folders
  * kubectl delete deployment = uninstalling an app
  * minikube delete = reinstalling the OS


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