Kubernetes 资源控制器使用指南

-o=custom-columns=<spec>   #使用逗号分隔的自定义列列表打印表格
-o=custom-columns-file=<filename> #使用文件中的自定义列模板打印表格
-o=json    #输出JSON 格式的API对象
-o=jsonpath=< template>       #打印jsonpath表达式中定义的字段
-o=jsonpath-file=<filename>   #打印由文件中的jsonpath表达式定义的字段
-o=name  #仅打印资源名称 
-o=wide  #以纯文本格式输出任何附加信息，对于Pod ，包含节点名称
-o=yaml  #输出 YAML 格式的 API 对象 

--v=0  #总是对操作人员可见。
--v=1  #合理的默认日志级别，如果您不需要详细输出。
--v=2  #可能与系统的重大变化相关的，有关稳定状态的信息和重要的日志信息。这是对大多数系统推荐的日志级别。
--v=3  #有关更改的扩展信息。
--v=4  #调试级别详细输出。
--v=6  #显示请求的资源。
--v=7  #显示 HTTP 请求的 header。
--v=8  #显示 HTTP 请求的内容。

# [ReplicationController]
# .spec.template是.spec的唯一必需字段
# 只允许.spec.template.spec.restartPolicy等于Always

apiVersion: v1
kind: ReplicationController
metadata:
  name: nginx
  namespace: prod
spec:
  replicas: 3
  selector:
    app: nginx
  spec:
    metadata:
      name: nginx
      labels:
        app: nginx
    spec:
      containers:
        - name: nginx
          image: nginx
          ports:
            - containerPort: 80

# 部署服务
$ kubectl apply -f ./replication.yaml
replicationcontroller/nginx created

# 检查RC的状态
$ kubectl describe rc/nginx
Pods Status:    3 Running / 0 Waiting / 0 Succeeded / 0 Failed

# [ReplicaSet]
# .spec.template是.spec的唯一必需字段
# 只允许.spec.template.spec.restartPolicy等于Always

apiVersion: apps/v1
kind: ReplicaSet
metadata:
  name: frontend
  namespace: prod
  labels:
    app: guestbook
    tier: frontend
spec:
  replicas: 3
  selector:
    matchLabels:
      tier: frontend
  template:
    metadata:
      labels:
        tier: frontend
    spec:
      containers:
      - name: php-redis
        image: gcr.io/google_samples/gb-frontend:v3
        - name: GET_HOSTS_FROM
          value: dns
        ports:
          containerPort: 80
        env:

# 部署服务
$ kubectl create -f ./frontend.yaml
replicaset.apps/frontend created

# 检查RC的状态
$ kubectl describe rs/frontend

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
  namespace: prod
  labels:
    app: nginx
spec:
  replicas: 3
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
        - name: nginx
          image: nginx:1.7.9
          ports:
            - containerPort: 80

# 部署服务
$ kubectl apply -f ./nginx-deployment.yaml

# 检查Deployments的状态
$ kubectl get deployments
NAME               DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
nginx-deployment   3         3         3            3           18s

#上述输出字段含义解释
NAME: 列出了集群中Deployments的名称
DESIRED: 显示应用程序的期望状态的所需副本数
CURRENT: 显示当前正在运行的副本数
UP-TO-DATE: 显示已更新以实现期望状态的副本数
AVAILABLE: 显示应用程序可供用户使用的副本数
AGE: 显示应用程序运行的时间量

# 查看Deployment展开状态
$ kubectl rollout status deployment/nginx-deployment

# 检查RC的状态
$ kubectl describe rs
NAME                          DESIRED   CURRENT   READY   AGE
nginx-deployment-75675f5897   3         3         3       18s

# 查看每个Pod自动生成的标签
$ kubectl get pods --show-labels
NAME                                READY   STATUS   LABELS
nginx-deployment-75675f5897-7ci7o   1/1     Running  app=nginx,pod-template-hash=3123191453
nginx-deployment-75675f5897-kzszj   1/1     Running  app=nginx,pod-template-hash=3123191453
nginx-deployment-75675f5897-qqcnn   1/1     Running  app=nginx,pod-template-hash=3123191453

# 更新nginx服务
$ kubectl set image deployment/nginx-deployment nginx=nginx:1.9.1
deployment/nginx-deployment image updated

# 编辑Deployment文件
$ kubectl edit deployment/nginx-deployment
deployment/nginx-deployment edited

# 查看展开状态
$ kubectl rollout status deployment/nginx-deployment
Waiting for rollout to finish: 2 out of 3 new replicas have been updated...
deployment/nginx-deployment successfully rolled out

# 检查RC的状态
$ kubectl get rs
NAME                          DESIRED   CURRENT   READY   AGE
nginx-deployment-1564180365   3         3         3       6s
nginx-deployment-2035384211   0         0         0       36s

# 查看Pod的状态(生成了新的Pods)
$ kubectl get pods
NAME                                READY     STATUS    RESTARTS   AGE
nginx-deployment-1564180365-khku8   1/1       Running   0          14s
nginx-deployment-1564180365-nacti   1/1       Running   0          14s
nginx-deployment-1564180365-z9gth   1/1       Running   0          14s

# 获取Deployment的更多信息
$ kubectl describe deployments

# 设置镜像来更新服务
$ kubectl set image deployment/nginx-deployment nginx=nginx:1.91
deployment.apps/nginx-deployment image updated

# 遇到问题展开状态来验证
# 通过如下命令来查看Deployment是否完成
$ kubectl rollout status deployment/nginx-deployment
Waiting for rollout to finish: 1 out of 3 new replicas have been updated...

# 查看RS状态
$ kubectl get rs
NAME                          DESIRED   CURRENT   READY   AGE
nginx-deployment-1564180365   3         3         3       25s
nginx-deployment-2035384211   0         0         0       36s
nginx-deployment-3066724191   1         1         0       6s

# 查看Pod状态
$ kubectl get pods
NAME                                READY     STATUS             RESTARTS   AGE
nginx-deployment-1564180365-70iae   1/1       Running            0          25s
nginx-deployment-1564180365-jbqqo   1/1       Running            0          25s
nginx-deployment-1564180365-hysrc   1/1       Running            0          25s
nginx-deployment-3066724191-08mng   0/1       ImagePullBackOff   0          6s

# 检查Deployment修改历史
$ kubectl rollout history deployment/nginx-deployment
deployments "nginx-deployment"
REVISION    CHANGE-CAUSE
1           kubectl apply --filename=https://k8s.io/examples/controllers/nginx-deployment.yaml --record=true
2           kubectl set image deployment.v1.apps/nginx-deployment nginx=nginx:1.9.1 --record=true
3           kubectl set image deployment.v1.apps/nginx-deployment nginx=nginx:1.91 --record=true

# 查看修改历史的详细信息
$ kubectl rollout history deployment/nginx-deployment --revision=2
deployments "nginx-deployment" revision 2
  Labels:       app=nginx
          pod-template-hash=1159050644
......

# 现在已决定撤消当前展开并回滚到以前的版本
$ kubectl rollout undo deployment/nginx-deployment
deployment/nginx-deployment

# 通过下面命令来回滚到特定修改版本
$ kubectl rollout undo deployment/nginx-deployment --to-revision=2
deployment/nginx-deployment

# 查看deployment状态
$ kubectl get deployment nginx-deployment
NAME               DESIRED   CURRENT   UP-TO-DATE   AVAILABLE   AGE
nginx-deployment   3         3         3            3           30m

# 获取Deployment描述信息
$ kubectl describe deployment nginx-deployment

# 扩容(3->10)
$ kubectl scale deployment/nginx-deployment --replicas=10
deployment.apps/nginx-deployment scaled

# 水平缩放
$ kubectl autoscale deployment/nginx-deployment --min=10 --max=15 --cpu-percent=80
deployment/nginx-deployment scaled

apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: deamonset-example
  labels:
    app: daemonset
spec:
  selector:
    matchLabels:
    name: deamonset-example
  template:
    metadata:
      labels:
        name: deamonset-example
    spec:
      containers:
        - name: daemonset-example
          image: hub.escapelife/nginx:v1

# 创建DaemonSet的Pod
kubectl apply -f ./daemonset-test.yaml

# 查看服务状态
kubectl get daemonsets
kubectl get pods --namespace default

apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: fluentd-elasticsearch
  namespace: kube-system
  labels:
    k8s-app: fluentd-logging
spec:
  selector:
    matchLabels:
      name: fluentd-elasticsearch
  template:
    metadata:
      labels:
        name: fluentd-elasticsearch
    spec:
      tolerations:
        - key: node-role.kubernetes.io/master
          effect: NoSchedule
      containers:
        - name: fluentd-elasticsearch
          image: quay.io/fluentd_elasticsearch/fluentd:v2.5.2
          resources:
            limits:
              memory: 200Mi
            requests:
              cpu: 100m
              memory: 200Mi
          volumeMounts:
            - name: varlog
              mountPath: /var/log
            - name: varlibdockercontainers
              mountPath: /var/lib/docker/containers
              readOnly: true
      terminationGracePeriodSeconds: 30
      volumes:
        - name: varlog
          hostPath:
            path: /var/log
        - name: varlibdockercontainers
          hostPath:
            path: /var/lib/docker/containers

# 创建DaemonSet的Pod
kubectl apply -f https://k8s.io/examples/controllers/daemonset.yaml

# 查看服务状态
kubectl get daemonsets.apps fluentd-elasticsearch --namespace kube-system
kubectl get pods --namespace kube-system --label name=fluentd-elasticsearch

apiVersion: v1
kind: Service
metadata:
  name: nginx
  labels:
    app: nginx
spec:
  clusterIP: None
  selector:
    app: nginx
  ports:
  - port: 80
    name: web

---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: web
spec:
  serviceName: "nginx"
  podManagementPolicy: "Parallel"
  replicas: 2
  ......

apiVersion: v1
kind: Service
metadata:
  name: nginx
  labels:
    app: nginx
spec:
  ports:
    - port: 80
      name: web
  clusterIP: None
  selector:
    app: nginx

---
apiVersion: apps/v1
kind: StatefulSet
metadata:
  name: web
spec:
  serviceName: "nginx"
  replicas: 2
  selector:
    matchLabels:
      app: nginx
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
        - name: nginx
          image: k8s.gcr.io/nginx-slim:0.8
          ports:
            - containerPort: 80
              name: web
          volumeMounts:
            - name: www
              mountPath: /usr/share/nginx/html
  volumeClaimTemplates:
    - metadata:
        name: www
      spec:
        accessModes: ["ReadWriteOnce"]
        resources:
          requests:
            storage: 1Gi

# 创建定义在web.yaml中的Headless Service和StatefulSet
$ sudo kubectl apply -f web.yaml
service/nginx created
statefulset.apps/web created

# 验证是否成功创建
$ sudo kubectl get service nginx
NAME      TYPE         CLUSTER-IP   EXTERNAL-IP   PORT(S)   AGE
nginx     ClusterIP    None         <none>        80/TCP    12s

$ sudo kubectl get statefulset web
NAME      DESIRED   CURRENT   AGE
web       2         1         20s

# 动态查看创建状态，发现是顺序创建Pod的
# 我们可以动态的看到web-0的Pod先创建完毕之后，web-1才会被启动
$ sudo kubectl get pods -w -l app=nginx
NAME      READY     STATUS              RESTARTS   AGE
web-0     0/1       Pending             0          0s
web-0     0/1       Pending             0          0s
web-0     0/1       ContainerCreating   0          0s
web-0     1/1       Running             0          19s
web-1     0/1       Pending             0          0s
web-1     0/1       Pending             0          0s
web-1     0/1       ContainerCreating   0          0s
web-1     1/1       Running             0          18s

# 获取StatefulSet的Pod
$ sudo kubectl get pods -l app=nginx
NAME      READY     STATUS    RESTARTS   AGE
web-0     1/1       Running   0          1m
web-1     1/1       Running   0          1m

# 使用稳定的网络身份标识
$ sudo kubectl exec web-0 -- bash -c \
    "for i in 0 1; do kubectl exec web-$i -- sh -c 'hostname'; done"
web-0

$ sudo kubectl exec web-1 -- bash -c \
    "for i in 0 1; do kubectl exec web-$i -- sh -c 'hostname'; done"
web-1

# 稳定的网络身份标识
$ sudo kubectl run -i --tty --image busybox:1.28 \
    dns-test --restart=Never --rm nslookup web-0.nginx
Server:    10.0.0.10
Address 1: 10.0.0.10 kube-dns.kube-system.svc.cluster.local

Name:      web-0.nginx
Address 1: 10.244.1.6

nslookup web-1.nginx
Server:    10.0.0.10
Address 1: 10.0.0.10 kube-dns.kube-system.svc.cluster.local

Name:      web-1.nginx
Address 1: 10.244.2.6

# 写入稳定的存储
$ sudo kubectl get pvc -l app=nginx
NAME        STATUS    VOLUME                                     CAPACITY   ACCESSMODES   AGE
www-web-0   Bound     pvc-15c268c7-b507-11e6-932f-42010a800002   1Gi        RWO           48s
www-web-1   Bound     pvc-15c79307-b507-11e6-932f-42010a800002   1Gi        RWO           48s

$ sudo kubectl delete pod -l app=nginx
pod "web-0" deleted
pod "web-1" deleted

# 对应的服务访问地址，我们可以间接访问
web-0.nginx.default.svc.cluster.local
web-1.nginx.default.svc.cluster.local
扩容/缩容 - StatefulSet

# 扩容
$ sudo kubectl scale sts web --replicas=5
statefulset.apps/web scaled

# 缩容
$ sudo kubectl patch sts web -p '{"spec":{"replicas":3}}'
statefulset.apps/web patched

# 五个存储仍然存在
$ sudo kubectl get pvc -l app=nginx
NAME        STATUS    VOLUME                                     CAPACITY   ACCESSMODES   AGE
www-web-0   Bound     pvc-15c268c7-b507-11e6-932f-42010a800002   1Gi        RWO           13h
www-web-1   Bound     pvc-15c79307-b507-11e6-932f-42010a800002   1Gi        RWO           13h
www-web-2   Bound     pvc-e1125b27-b508-11e6-932f-42010a800002   1Gi        RWO           13h
www-web-3   Bound     pvc-e1176df6-b508-11e6-932f-42010a800002   1Gi        RWO           13h
www-web-4   Bound     pvc-e11bb5f8-b508-11e6-932f-42010a800002   1Gi        RWO           13h

# Patch web StatefulSet 来执行 RollingUpdate 更新策略
$ sudo kubectl patch statefulset web -p '{"spec":{"updateStrategy":{"type":"RollingUpdate"}}}'
statefulset.apps/web patched

# 在一个终端窗口中 patch web StatefulSet 来再次的改变容器镜像
$ sudo kubectl patch statefulset web --type='json' \
    -p='[{"op": "replace", "path": "/spec/template/spec/containers/0/image", \
    "value":"gcr.io/google_containers/nginx-slim:0.8"}]'
statefulset.apps/web patched

# 删除StatefulSet
kubectl delete statefulset web
statefulset.apps "web" deleted

# 删除Pod
kubectl delete pod web-0
pod "web-0" deleted

apiVersion: batch/v1
kind: Job
metadata:
  name: pi
spec:
  restartPolicy: OnFailure
  backoffLimit: 5 # timeout
  activeDeadlineSeconds: 100 # timeout
  ttlSecondsAfterFinished: 100 # ttl
  template:
    spec:
      containers:
        - name: pi
          image: perl
          command: ["perl", "-Mbignum=bpi", "-wle", "print bpi(2000)"]
      restartPolicy: Never
  backoffLimit: 4

# 使用下面的命令来运行此示例
$ sduo kubectl apply -f https://kubernetes.io/examples/controllers/job.yaml
job.batch/pi created

# 来检查Job的状态
$ sudo kubectl describe jobs/pi

# 查看Job对应的已完成的Pods
$ sudo kubectl get pods

# 查看PI输出结果
$ pods=$(suod kubectl get pods --selector=job-name=pi --output=jsonpath={.items..metadata.name})
$ sduo kubectl logs $pods
3.141592653589793238462......

apiVersion: batch/v1beta1
kind: 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

# 创建
$ sudo kubectl create -f cronjob.yaml
cronjob "hello" created

# 查看
$ sudo kubectl get jobs
NAME               DESIRED   SUCCESSFUL   AGE
hello-1202039034   1         1            49s

# 查看
$ sudo kubectl get cronjob
NAME      SCHEDULE      SUSPEND   ACTIVE    LAST-SCHEDULE
hello     */1 * * * *   False     0         <none>

# 输出
$ pods=$(sudo kubectl get pods --selector=job-name=hello-1202039034 --output=jsonpath={.items..metadata.name})
$ sudo kubectl logs $pods
Mon Aug 29 21:34:09 UTC 2020
Hello from the Kubernetes cluster

# 删除
$ sudo kubectl delete cronjob hello
cronjob "hello" deleted

# 逐个删除
$ kubectl get jobs
NAME               DESIRED   SUCCESSFUL   AGE
hello-1201907962   1         1            11m
hello-1202039034   1         1            8m
...

$ kubectl delete jobs hello-1201907962 hello-1202039034 ...
job "hello-1201907962" deleted
job "hello-1202039034" deleted
...

# 强制删除
$ sudo kubectl delete jobs --all