Interactive notes/commands for kubectl, which may help for certifications:

Command
k -n NAMESPACE run NAME –image=httpd:alpine –dry-run=client -oyaml > pod.ya
k replace –force -f ./pod.yaml
k create configmap NAME –from-literal key=value –dry-run=client -oyaml > cm.yml
k create deploy NAME –image=httpd:alpine -oyaml –dry-run=client > deploy.yaml
k exec desploy NAME – sh
k scale deploy NAME –replicas 0
k get crd NAME -oyaml
k expose deploy NAME –port 80

Templates:

Pod:

apiVersion: v1
kind: Pod
metadata:
  labels:
    run: my-pod
  name: my-pod
  namespace: my-namespace
spec:
  containers:
  - image: httpd:alpine
    resources:
      requests:
        memory: "30Mi"
        cpu: "30m"
      limits:
        memory: "30Mi"
        cpu: "300m"
    name: httpd-container
  restartPolicy: Always

Deployment:

apiVersion: apps/v1
kind: Deployment
metadata:
  creationTimestamp: null
  labels:
    app: my-label
  name: my-label
spec:
  replicas: 1
  selector:
    matchLabels:
      app: my-label
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: my-label
    spec:
      containers:
      - image: httpd:alpine
        name: httpd
        resources: {}
        readinessProbe:
          exec:
            command:
            - stat
            - /tmp/ready
          initialDelaySeconds: 10
          periodSeconds: 5

Service:

apiVersion: v1
kind: Service
metadata:
  labels:
    app: my-app
  name: my-app
spec:
  ports:
  - port: 80
    protocol: TCP
    targetPort: 80
    nodePort: 30090
  selector:
    app: my-app
    version: v1
  type: NodePort

Ingress:

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: cafe-ingress
spec:
  ingressClassName: nginx
  #tls:
  #- hosts:
  #  - cafe.local
  #  secretName: cafe-secret
  rules:
  - host: cafe.local
    http:
      paths:
      - path: /tea
        pathType: Prefix
        backend:
          service:
            name: tea-svc
            port:
              number: 80
      - path: /coffee
        pathType: Prefix
        backend:
          service:
            name: coffee-svc
            port:
              number: 80

Egress:

apiVersion: networking.k8s.io/v1
kind: NetworkPolicy
metadata:
  name: np
  namespace: space1
spec:
  podSelector: {}
  policyTypes:
  - Egress
  egress:
  - ports:
    - port: 53
      protocol: TCP
    - port: 53
      protocol: UDP
  - to:
     - namespaceSelector:
        matchLabels:
         kubernetes.io/metadata.name: space2