kubernetes 控制器

2021年09月15日 阅读数:3
这篇文章主要向大家介绍kubernetes 控制器,主要内容包括基础应用、实用技巧、原理机制等方面,希望对大家有所帮助。

1.基础

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.滚动升级

vim de.yaml #修改yaml里的镜像版本
kubernetes 控制器nginx

 apiVersion: apps/v1
kind: Deployment
metadata:
  name: myapp-deploy
  namespace: default
spec:
  replicas: 5
  selector:
    matchLabels:
      app: myapp
      release: dev
  strategy:
    rollingUpdate:
    #设置策略为滚动更新,还有一个重建更新,所有一块儿结束一块儿新建 不友好这里就不介绍了
      maxSurge: 1
      #最大可超出预设值1个容器
      maxUnavailable: 0
      #最大可有0个容器不可用 ,总体表示更新时可同时可有6个容器,必须保证有5个容器可用
  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vim

[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
kubernetes 控制器
能够看到当前镜像版本已经换成了v2 且模板也变了,以前的v1版本还保这方便回滚,yaml文件内容修改一次就会当作一次更新,最后一串数字就是经过yaml文件计算出来的
注意: deployment的pod模板被更改时才会建立新的修订版本,例如更新模板标签或者容器镜像能够触发滚动更新, 其它操做例如扩展副本数将不会触发deployment的更新操做api

金丝雀发布

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"
#原理就是先升级一个容器的版本,执行pause 暂停升级任务,待升级的那个容器通过真实用户测试后无错后解除暂停
kubernetes 控制器
kubectl get rs -o wide #查看控制器能看到,有1个v3版,5个v2版本,出现6个的缘由是我滚动策略定义了升级可容许存在6个
kubectl rollout resume deploy myapp-deploy
#解除暂停
kubernetes 控制器
#解除暂停后能看到,v2版本在一点点的关闭向v3版转移,最终v2所有关闭,v3版5个容器所有正常上线markdown

回滚

 kubectl rollout history deployment/nginx-deployment
 #查看升级历史记录
 kubectl rollout history deployment/nginx-deployment --revision=2
 #查看某个升级历史记录的的详细信息
kubectl rollout undo deployment/nginx-deployment
#回滚到上一个版本
kubectl rollout undo deployment/nginx-deployment --to-revision=2
#回滚到指定版本