kubernetes 控制器

1.基礎

apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp-deploy
  namespace: default
spec:
  replicas: 2
  selector:
    matchLabels:
      app: myapp
      release: dev
  template:
    metadata:
      labels:
        app: myapp
        release: dev
    spec:
      containers:
      - name: myapp-rongqi
        image: ikubernetes/myapp:v1

2.滾動升級

vim de.yaml #修改yaml里的鏡像版本

 apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp-deploy
  namespace: default
spec:
  replicas: 5
  selector:
    matchLabels:
      app: myapp
      release: dev
  strategy:
    rollingUpdate:
    #設置策略為滾動更新，還有一個重建更新，全部一起結束一起新建 不友好這里就不介紹了
      maxSurge: 1
      #最大可超出預設值1個容器
      maxUnavailable: 0
      #最大可有0個容器不可用 ,整體表示更新時可同時可有6個容器,必須保證有5個容器可用
  template:
    metadata:
      labels:
        app: myapp
        release: dev
    spec:
      containers:
      - name: myapp-rongqi
        image: ikubernetes/myapp:v1

kubectl apply -f de.yaml #用apply更新配置

[root@cs25 ~]# kubectl get pod  -l app=myapp -w
NAME                            READY   STATUS    RESTARTS   AGE
myapp-deploy-576d479bcc-bt7hz   1/1     Running   0          47m
myapp-deploy-576d479bcc-bzqwv   1/1     Running   0          11m
myapp-deploy-576d479bcc-hf6kb   1/1     Running   0          47m
myapp-deploy-576d479bcc-hgb6w   1/1     Running   0          11m
myapp-deploy-576d479bcc-vztqp   1/1     Running   0          11m
myapp-deploy-7f969b64fb-2frdn   0/1     Pending   0          0s
myapp-deploy-576d479bcc-vztqp   1/1     Terminating   0          12m
myapp-deploy-7f969b64fb-6lhjw   0/1     Pending       0          0s
myapp-deploy-7f969b64fb-2frdn   0/1     Pending       0          0s
myapp-deploy-7f969b64fb-6lhjw   0/1     Pending       0          0s
myapp-deploy-7f969b64fb-5ms8f   0/1     Pending       0          0s
myapp-deploy-7f969b64fb-5ms8f   0/1     Pending       0          0s
myapp-deploy-7f969b64fb-6lhjw   0/1     ContainerCreating   0          1s
myapp-deploy-7f969b64fb-2frdn   0/1     ContainerCreating   0          1s
myapp-deploy-7f969b64fb-5ms8f   0/1     ContainerCreating   0          0s
myapp-deploy-7f969b64fb-2frdn   0/1     ContainerCreating   0          35s
myapp-deploy-7f969b64fb-5ms8f   0/1     ContainerCreating   0          35s
myapp-deploy-7f969b64fb-6lhjw   0/1     ContainerCreating   0          36s
myapp-deploy-576d479bcc-vztqp   0/1     Terminating         0          12m
myapp-deploy-576d479bcc-vztqp   0/1     Terminating         0          12m
myapp-deploy-576d479bcc-vztqp   0/1     Terminating         0          12m
myapp-deploy-7f969b64fb-5ms8f   1/1     Running             0          43s
myapp-deploy-7f969b64fb-2frdn   1/1     Running             0          47s
myapp-deploy-7f969b64fb-6lhjw   1/1     Running             0          51s
myapp-deploy-576d479bcc-hgb6w   1/1     Terminating         0          13m
myapp-deploy-576d479bcc-bzqwv   1/1     Terminating         0          13m
myapp-deploy-576d479bcc-bt7hz   1/1     Terminating         0          49m
myapp-deploy-7f969b64fb-gprvk   0/1     Pending             0          0s
myapp-deploy-7f969b64fb-fwdbr   0/1     Pending             0          0s
myapp-deploy-7f969b64fb-fwdbr   0/1     Pending             0          1s
myapp-deploy-7f969b64fb-gprvk   0/1     Pending             0          1s
myapp-deploy-7f969b64fb-fwdbr   0/1     ContainerCreating   0          1s
myapp-deploy-7f969b64fb-gprvk   0/1     ContainerCreating   0          1s
myapp-deploy-576d479bcc-hgb6w   0/1     Terminating         0          13m
myapp-deploy-576d479bcc-bzqwv   0/1     Terminating         0          13m
myapp-deploy-7f969b64fb-fwdbr   0/1     ContainerCreating   0          18s
myapp-deploy-7f969b64fb-gprvk   0/1     ContainerCreating   0          19s
myapp-deploy-576d479bcc-hgb6w   0/1     Terminating         0          13m
myapp-deploy-576d479bcc-bt7hz   0/1     Terminating         0          49m
myapp-deploy-576d479bcc-bzqwv   0/1     Terminating         0          13m
myapp-deploy-7f969b64fb-gprvk   1/1     Running             0          20s
myapp-deploy-7f969b64fb-fwdbr   1/1     Running             0          20s

kubectl get rs -o wide #使用命令查看

可以看到當前鏡像版本已經換成了v2 且模板也變了，之前的v1版本還保這方便回滾，yaml文件內容修改一次就會當做一次更新，最后一串數字就是通過yaml文件計算出來的
注意： deployment的pod模板被更改時才會創建新的修訂版本，例如更新模板標簽或者容器鏡像可以觸發滾動更新, 其它操作例如擴展副本數將不會觸發deployment的更新操作

金絲雀發布

kubectl set image deploy myapp-deploy myapp-rongqi=ikubernetes/myapp:v3 && kubectl rollout pause deploy myapp-deploy
#kubectl set image deploy "控制器Name" "容器name"=ikubernetes/myapp:v3 && kubectl rollout pause deploy "控制器Name"
#原理就是先升級一個容器的版本，執行pause 暫停升級任務，待升級的那個容器經過真實用戶測試后無錯后解除暫停

kubectl get rs -o wide #查看控制器能看到，有1個v3版，5個v2版本，出現6個的原因是我滾動策略定義了升級可允許存在6個
kubectl rollout resume deploy myapp-deploy
#解除暫停

#解除暫停后能看到，v2版本在一點點的關閉向v3版轉移，最終v2全部關閉，v3版5個容器全部正常上線

回滾

 kubectl rollout history deployment/nginx-deployment
 #查看升級歷史記錄
 kubectl rollout history deployment/nginx-deployment --revision=2
 #查看某個升級歷史記錄的的詳細信息
kubectl rollout undo deployment/nginx-deployment
#回滾到上一個版本
kubectl rollout undo deployment/nginx-deployment --to-revision=2
#回滾到指定版本