Kubernetes(K8s)2020版 controller详解：有（无头service）无状态应用（原来）守护进程一次性定时任务 secret configmap （5）

我会带着你远行 2022-08-29 09:48 17阅读 0赞

# 一图详解： #

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxMTIwNjMxMTU3_size_16_color_FFFFFF_t_70]

## 无头service + 有状态部署 ##

apiVersion: v1
    kind: Service
    metadata:
      name: nginx
      labels:
        app: nginx
    spec:
      ports:
      - port: 80
        name: web
      clusterIP: None #None
      selector:
        app: nginx
    
    ---
    
    apiVersion: apps/v1beta1
    kind: StatefulSet #statefulSet
    metadata:
      name: nginx-statefulset
      namespace: default
    spec:
      serviceName: nginx
      replicas: 3
      selector:
        matchLabels:
          app: nginx
      template:
        metadata:
          labels:
            app: nginx
        spec:
          containers:
          - name: nginx
            image: nginx:latest
            ports:
            - containerPort: 80

## 部署守护进程 ##

*  每个pod中都部署一个

kubectl delete statefulset --all
     kubectl delete svc nginx
    
    kubectl delete DaemonSet --all 或  kubectl delete -f job.yaml   如果是 ds.yaml生成的，后缀就用它

apiVersion: apps/v1
    kind: DaemonSet #守护进程
    metadata:
      name: ds-test 
      labels:
        app: filebeat
    spec:
      selector:
        matchLabels:
          app: filebeat
      template:
        metadata:
          labels:
            app: filebeat
        spec:
          containers:
          - name: logs
            image: nginx
            ports:
            - containerPort: 80
            volumeMounts:
            - name: varlog
              mountPath: /tmp/log
          volumes:
          - name: varlog
            hostPath:
              path: /var/log

kubectl exec -it ds-test-85lgr bash #进入这个pod
     
     ls /tmp/log

## 一次性任务 ##

apiVersion: batch/v1
    kind: Job
    metadata:
      name: pi
    spec:
      template:
        spec:
          containers:
          - name: pi
            image: perl
            command: ["perl",  "-Mbignum=bpi", "-wle", "print bpi(2000)"]
          restartPolicy: Never
      backoffLimit: 4 #失败之后，在尝试4次

docker pull perl 查看 ???
    
    # 查看所有的 jobs
    kubectl get jobs
    
    # 查看pods
    [root@k8smaster ~]# kubectl get pods
    NAME            READY   STATUS      RESTARTS   AGE
    pi-mf28k        0/1     Completed   0          4m55s
    
    # 任务已经完成
    
    # 查看结果 机制
    kubectl logs pi-mf28k
    
    # 根据文件删除
    kubectl delete -f job.yaml

## 定时任务 ##

apiVersion: batch/v1beta1
    kind: CronJob #cronJob
    metadata:
      name: hello
    spec:
      schedule: "*/1 * * * *"
      jobTemplate:
        spec:
          template:
            spec:
              containers:
              - name: hello
                image: busybox
                args:
                - /bin/sh
                - -c
                - date; echo Hello from the Kubernetes cluster
              restartPolicy: OnFailure

kubectl get cronjobs
    kubectl logs hello-xxxx

# secret 总览图 #

# 输出一个命令：
    [root@k8smaster ~]# echo -n 'admin' | base64
    YWRtaW4=

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxMTIwNjMxMTU3_size_16_color_FFFFFF_t_70 1]

## 创建secret ##

apiVersion: v1
    kind: Secret
    metadata:
      name: mysecret
    type: Opaque
    data:
      username: YWRtaW4=
      password: MWYyZDFlMmU2N2Rm

[root@k8smaster ~]# vim secret.yaml
    # 运行yaml 注意用 create
    [root@k8smaster ~]# kubectl create -f secret.yaml
    secret/mysecret created
    
    # 获得 secret
    [root@k8smaster ~]# kubectl get secret
    
    NAME                  TYPE                                  DATA   AGE
    default-token-cbx9c   kubernetes.io/service-account-token   3      30d
    mysecret              Opaque                                2      8s

## 1. 变量形式挂载 ##

apiVersion: v1
    kind: Pod
    metadata:
      name: mypod
    spec:
      containers:
      - name: nginx
        image: nginx
        env:
          - name: SECRET_USERNAME
            valueFrom:
              secretKeyRef:
                name: mysecret
                key: username
          - name: SECRET_PASSWORD
            valueFrom:
              secretKeyRef:
                name: mysecret
                key: password

# 运行yaml 用 apply
    kubectl apply -f secret-var.yaml
    pod/mypod created
    
    #进入
    kubectl exec -it mypod bash
    
    # 输出结果
    root@mypod:/# echo $SECRET_USERNAME
    admin
    
    kubectl delete -f secret-var.yaml

## 2. volume数据卷的形式挂载 ##

apiVersion: v1
    kind: Pod
    metadata:
      name: mypod
    spec:
      containers:
      - name: nginx
        image: nginx
        volumeMounts:
        - name: foo
          mountPath: "/etc/foo"
          readOnly: true
      volumes:
      - name: foo
        secret:
          secretName: mysecret

# 进入pod
    kubectl exec -it mypod bash
    
    # 进入到目录
    root@mypod:/# ls /etc/foo
    password  username
    
    cat pssword 能看看到值
    
    kubectl delete pod --all

# configmap #

redis.host=127.0.0.1
    redis.port=6379
    redis.password=123456

# 创建 configmap
    kubectl create configmap redis-config --from-file=redis.properties
    
    # 获得
    kubectl get cm
    # 获得这个 config的详细
    kubectl describe cm redis-config

## Volume挂载 ##

apiVersion: v1
    kind: Pod
    metadata:
      name: mypod
    spec:
      containers:
        - name: busybox
          image: busybox
          command: [ "/bin/sh","-c","cat /etc/config/redis.properties" ]
          volumeMounts:
          - name: config-volume
            mountPath: /etc/config
      volumes:
        - name: config-volume
          configMap:
            name: redis-config
      restartPolicy: Never

# 运行
    kubectl apply -f cm.yaml
    # 查看日志
    kubectl logs mypod
    # 删除
    kubectl delete -f cm.yaml

## 以变量形式挂载 ##

### 创建 （重新写一个 configMap） ###

apiVersion: v1
    kind: ConfigMap
    metadata:
      name: myconfig
      namespace: default
    data:
      special.level: info
      special.type: hello

kubectl apply -f myconfig.yaml
    kubectl get cm

### 用pod进行读取 ###

apiVersion: v1
    kind: Pod
    metadata:
      name: mypod
    spec:
      containers:
        - name: busybox
          image: busybox
          command: [ "/bin/sh", "-c", "echo $(LEVEL) $(TYPE)" ]
          env:
            - name: LEVEL
              valueFrom:
                configMapKeyRef:
                  name: myconfig
                  key: special.level
            - name: TYPE
              valueFrom:
                configMapKeyRef:
                  name: myconfig
                  key: special.type
      restartPolicy: Never

# 运行
    kubectl apply -f config-var.yaml
    
    # 查看日志
    kubectl logs mypod

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxMTIwNjMxMTU3_size_16_color_FFFFFF_t_70 2]

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