k8s实战三 创建无状态应用

1 关于nginx的无状态应用

关于nginx1.7的版本
cat deployment.yaml

apiVersion: apps/v1 # for versions before 1.9.0 use apps/v1beta2
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  selector:
    matchLabels:
      app: nginx
  replicas: 2 # tells deployment to run 2 pods matching the template
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.7.9
        ports:
        - containerPort: 80

通过yaml创建pod

kubectl apply -f deployment.yaml

查看 deployment的细节

kubectl describe deployment nginx-deployment

查看所有相关的pod （通过selector）

kubectl get pods -l app=nginx

查看详细的pod

kubectl describe pod <pod-name>

升级deployment

更改deployment.yaml如下

apiVersion: apps/v1 # for versions before 1.9.0 use apps/v1beta2
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  selector:
    matchLabels:
      app: nginx
  replicas: 2
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.8 # Update the version of nginx from 1.7.9 to 1.8
        ports:
        - containerPort: 80

开始部署

kubectl apply -f deployment.yaml

查看更新状态

kubectl get pods -l app=nginx

实时更新 replica 数

更改deployment.yaml

apiVersion: apps/v1 # for versions before 1.9.0 use apps/v1beta2
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  selector:
    matchLabels:
      app: nginx
  replicas: 4 # Update the replicas from 2 to 4
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: nginx:1.8
        ports:
        - containerPort: 80

开始部署

kubectl apply -f deployment.yaml

查看更新状态

kubectl get pods -l app=nginx

删除deployment

kubectl delete deployment nginx-deployment