CDK Entest

Introduction#

this section shows some practices,

question 6 deployment blue/green
question 7 deployment and rollout
question 8 deployment canary
question 9 helm chart

Question 6 Blue/Green#

create blue.yaml for blue deployment
create prod_service.yaml with blue backend
create test_service.yaml with blue backend
create green backend, and update test_service.yaml
switch prod_service.yaml to use green backend

create blue deployment

kubectl create deployment blue-deploy --image=paulbouwer/hello-kubernetes:1.5 --port=8080 --dry-run=client --output=yaml > q5_blue_deploy.yaml

then update the q5_blue_deploy.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  creationTimestamp: null
  labels:
    app: q5-blue
  name: q5-blue
spec:
  replicas: 1
  selector:
    matchLabels:
      app: q5-blue
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: q5-blue
    spec:
      containers:
        - image: paulbouwer/hello-kubernetes:1.5
          name: hello
          ports:
            - containerPort: 8080
          resources: {}
status: {}

get the pod internal ip then take note it

kubect get pods --output=wide

shell into a temporary busybox to check it

kubect run test --image=busybox -it --rm --command -- /bin/sh

then check the service

wget -O- POD_IP:8080

expose blue backend as a service on port 80 using aws load balancer

kubectl create service q5-service --tcp=80:8080 --dry-run=client --output=yaml > q5_service.yaml

then update the q5_service.yaml as

apiVersion: v1
kind: Service
metadata:
  creationTimestamp: null
  labels:
    app: q5-service
  name: q5-service
spec:
  ports:
    - port: 80
      protocol: TCP
      targetPort: 8080
  selector:
    app: q5-blue
  type: LoadBalancer
status:
  loadBalancer: {}

get the load balancer endpoint which should be publicly accessible

kubect get service

then curl to the the endpoint, please wait a minut for the endpoint readly (aws classic load balancer behind it )

curl http://endpoint:80

now create the green deployment

apiVersion: apps/v1
kind: Deployment
metadata:
  creationTimestamp: null
  labels:
    app: q5-green
  name: q5-green
spec:
  replicas: 1
  selector:
    matchLabels:
      app: q5-green
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: q5-green
    spec:
      containers:
        - image: paulbouwer/hello-kubernetes:1.5
          name: hello
          ports:
            - containerPort: 8080
          resources: {}
status: {}

swich the service to the green deployment by update and apply change to the q5_service.yaml

apiVersion: v1
kind: Service
metadata:
  creationTimestamp: null
  labels:
    app: q5-service
  name: q5-service
spec:
  ports:
    - port: 80
      protocol: TCP
      targetPort: 8080
  selector:
    app: q5-green
  type: LoadBalancer
status:
  loadBalancer: {}

apply changle

kubectl apply -f q5_service.yaml

open the http://endpoint and notice the pod change blue pod => green pod

Question 7 Rollout#

create a deployment named with three replicas, pods should use image nginx and the name nginx, deployment uses label tier=backend, pod label app=v1
list deployment and ensure the correct number of replicas are running
update the image to nginx:latest, verify that the change has been rolled out to all replicas
scale the deployment to 5 replicas, have a look at the deployment rollout history
revert the deployment to revision 1, ensure the pods are running the image nginx

create a deployment

kubectl create deployment deploy --image=nginx --dry-run=client --output=yaml > q11.yaml

update the yaml with label for deployment and pod, replicas=3

apiVersion: apps/v1
kind: Deployment
metadata:
  creationTimestamp: null
  labels:
    tier: backend
  name: deploy
spec:
  replicas: 3
  selector:
    matchLabels:
      app: v1
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: v1
    spec:
      containers:
        - image: nginx
          name: nginx
          resources: {}
status: {}

deploy or apply

kubectl create -f q11.yaml

list deployment

kubectl get deployments

update image nginx to nginx:latest for the deployments (deploy)

kubectl set image deployment/deploy nginx=nginx:latest

rollout history to see how many revision

kubectl rollout history

check one revision to confirm that nginx:latest is running

kubectl rollout history deployment/deploy --revision=2

double check

kubectl get deployment/deploy

scale the deploy replicas to 5

kubectl scale --replicas=5 -f q11.yaml

check the rollout history

kubectl rollout history deployment/deploy

revert to reversion 1

kubectl rollout undo deployment/deploy --revision=1

double check the nginx:nginx is running (not the latest)

kubectl rollout history deployment/deploy --revision=3

kubectl get describe pod PODNAME

Question 8 Canary#

(TODO)

Question 9 Helm Chart#

step 1. install heml

step 2. initialize helm

helm repo add bitnami https://charts.bitnami.com/bitnami

check

helm search repo bitnami

step 3. install mysql by heml

helm install bitnami/mysql --generate-name

step 4. follow the guide from terminal to setup db credentials and access the mysql

step 5. uninstall the mysql

hel list to get the current installed version of mysql-xxx

heml list

then

heml uninstall mysql-xxx