yuttasakcom/k8s-exercise

Kubernetes Exercise

Table of Contents

• POD
• SERVICE
• Replicaset
• Deployment
• Namespace
• Persistante-Volume

POD

• kubectl apply -f 1.pod.yaml
• kubectl get all
• kubectl delete -f 1.pod.yaml
• kubectl describe pod {pod-name}
• kubectl get po --show-labels

apiVersion: v1
kind: Pod
metadata:
  name: webapp
  labels:
    app: webapp
spec:
  containers:
    - name: webapp
      image: jmalloc/echo-server

SERVICE

• kubectl describe svc service-webapp

kind: Service
apiVersion: v1
metadata:
  name: service-webapp
spec:
  selector:
    app: webapp
  ports:
    - name: http
      port: 8080
      nodePort: 30080
  type: NodePort

• kubectl exec -it {pod-name} sh
  • nslookup database

apiVersion: v1
kind: Pod
metadata:
  name: mysql
  labels:
    app: mysql
spec:
  containers:
    - name: mysql
      image: mysql:5
      env:
        - name: MYSQL_ROOT_PASSWORD
          value: password
        - name: MYSQL_DATABASE
          value: fleetman
---
kind: Service
apiVersion: v1
metadata:
  name: database
spec:
  selector:
    app: mysql
  ports:
    - port: 3306
  type: ClusterIP

Replicaset

apiVersion: apps/v1
kind: ReplicaSet
metadata:
  name: webapp
spec:
  selector:
    matchLabels:
      app: webapp
  replicas: 2
  template:
    metadata:
      labels:
        app: webapp
    spec:
      containers:
        - name: webapp
          image: richardchesterwood/k8s-fleetman-webapp-angular:release0-5
---
apiVersion: v1
kind: Service
metadata:
  name: fleetman-webapp
spec:
  selector:
    app: webapp
  ports:
    - name: http
      port: 80
      nodePort: 30080
  type: NodePort

Deployment

• kubectl rollout history deploy webapp
• kubectl rollout status deploy webapp
• kubectl rollout undo deploy webapp

apiVersion: apps/v1
kind: Deployment
metadata:
  name: webapp
spec:
  minReadySeconds: 30
  selector:
    matchLabels:
      app: webapp
  replicas: 2
  template:
    metadata:
      labels:
        app: webapp
    spec:
      containers:
        - name: webapp
          image: richardchesterwood/k8s-fleetman-webapp-angular:release0
---
apiVersion: v1
kind: Service
metadata:
  name: fleetman-webapp
spec:
  selector:
    app: webapp
  ports:
    - name: http
      port: 80
      nodePort: 30080
  type: NodePort

Namespace

• kubectl get namespace
• kubectl get po -n kube-system

Persistante-Volume

apiVersion: apps/v1
kind: Deployment
metadata:
  name: mongodb
spec:
  selector:
    matchLabels:
      app: mongodb
  replicas: 1
  template:
    metadata:
      labels:
        app: mongodb
    spec:
      containers:
        - name: mongodb
          image: mongo:3.6.5-jessie
          volumeMounts:
            - name: mongo-persistent-storage
              mountPath: /data/db
      volumes:
        - name: mongo-persistent-storage
          hostPath:
            path: /mnt/some/directory/structure/
            type: DirectoryOrCreate
---
apiVersion: v1
kind: Service
metadata:
  name: service-mongodb
spec:
  selector:
    app: mongodb
  ports:
    - name: mongoport
      port: 27017
  type: ClusterIP

Persistant-Volume-Claim

• kubectl get pv
• kubectl get pvc

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: mongo-pvc
spec:
  storageClassName: mylocalstorage
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 8Gi
---
apiVersion: v1
kind: PersistentVolume
metadata:
  name: local-storage
spec:
  storageClassName: mylocalstorage
  capacity:
    storage: 8Gi
  accessModes:
    - ReadWriteOnce
  hostPath:
    path: '/mnt/some/directory/structure/'
    type: DirectoryOrCreate