QUIC 协议的优势-CFANZ编程社区

cloud 07

一、k8s服务管理

创建后端应用

固定 IP 服务

[root@master ~]# vim websvc.yaml 
---
kind: Service
apiVersion: v1
metadata:
  name: websvc
spec:
  type: ClusterIP
  clusterIP: 10.245.1.80    # 可以设置 ClusterIP
  selector:
    app: web
  ports:
  - protocol: TCP
    port: 80
    targetPort: 80

[root@master ~]# kubectl replace --force -f websvc.yaml 
service "websvc" deleted
service/websvc replaced
[root@master ~]# kubectl get service
NAME         TYPE        CLUSTER-IP    EXTERNAL-IP   PORT(S)
kubernetes   ClusterIP   10.245.0.1    <none>        443/TCP
websvc       ClusterIP   10.245.1.80   <none>        80/TCP

端口别名

安装控制器

三、Dashboard 安装

#下面给大家介绍下新的k8s插件

web 管理插件

安装 Dashboard

cloud 08

#上一小节讲过K8S的有控制组件和计算组件。现在我们一起来深入研究K8S的控制组件。

一、Deployment

资源清单文件

[root@master ~]# kubectl create deployment myweb --image=myos:httpd --dry-run=client -o yaml
[root@master ~]# vim mydeploy.yaml
---
kind: Deployment          # 资源对象类型
apiVersion: apps/v1       # 版本
metadata:                 # 元数据
  name: mydeploy          # 名称
spec:                     # 详细定义
  replicas: 3             # 副本数量
  selector:               # 定义标签选择器
    matchLabels:          # 支持 matchExpressions 表达式语法
      app: deploy-httpd   # 通过标签来确定那个 Pod 由它来管理
  template:               # 定义用来创建 Pod 的模板,以下为 Pod 定义
    metadata:
      labels:
        app: deploy-httpd
    spec:
      containers:
      - name: apache
        image: myos:httpd

配置案例

# 创建控制器
[root@master ~]# kubectl apply -f mydeploy.yaml 
deployment.apps/mydeploy created

[root@master ~]# kubectl get deployments
NAME       READY   UP-TO-DATE   AVAILABLE   AGE
mydeploy   3/3     3            3           1s

# 控制器自动创建 ReplicaSet
[root@master ~]# kubectl get replicasets 
NAME                  DESIRED   CURRENT   READY   AGE
mydeploy-76f96b85df   3         3         3       2s

# 控制器自动创建 Pod
[root@master ~]# kubectl get pods
NAME                        READY   STATUS    RESTARTS   AGE
mydeploy-76f96b85df-5gng9   1/1     Running   0          3s
mydeploy-76f96b85df-vsfrw   1/1     Running   0          3s
mydeploy-76f96b85df-z9x95   1/1     Running   0          3s

# 集群自维护自治理
[root@master ~]# kubectl delete pod --all 
pod "mydeploy-76f96b85df-5gng9" deleted
pod "mydeploy-76f96b85df-vsfrw" deleted
pod "mydeploy-76f96b85df-z9x95" deleted

# 删除后自动重新创建
[root@master ~]# kubectl get pods
NAME                        READY   STATUS    RESTARTS   AGE
mydeploy-76f96b85df-7dvwh   1/1     Running   0          7s
mydeploy-76f96b85df-kpbz4   1/1     Running   0          7s
mydeploy-76f96b85df-kr2zq   1/1     Running   0          7s

集群服务

清理资源对象

# 删除控制器时会自动回收自己创建的 Pod
[root@master ~]# kubectl delete deployments mydeploy
deployment.apps "mydeploy" deleted

二、DaemonSet

配置案例

清理资源对象

# 删除控制器
[root@master ~]# kubectl delete daemonsets myds
daemonset.apps "myds" deleted

三、Job、CronJob

Job 控制器

# 资源文件模板
[root@master ~]# kubectl create job myjob --image=myos:8.5 --dry-run=client -o yaml -- sleep 3
[root@master ~]# vim myjob.yaml 
---
kind: Job
apiVersion: batch/v1
metadata:
  name: myjob
spec:
  template:  # 以下定义 Pod 模板
    metadata: {}
    spec:
      restartPolicy: OnFailure
      containers:
      - name: myjob
        image: myos:8.5
        command: ["/bin/sh"]
        args:
        - -c
        - |
          sleep 3
          exit $((RANDOM%2))

[root@master ~]# kubectl apply -f myjob.yaml 
job.batch/myjob created

# 失败了会重启
[root@master ~]# kubectl get pods -l job-name=myjob -w
NAME             READY   STATUS      RESTARTS     AGE
myjob--1-lrtbk   1/1     Running     0            2s
myjob--1-lrtbk   0/1     Error       0            4s
myjob--1-lrtbk   1/1     Running     1 (1s ago)   5s
myjob--1-lrtbk   0/1     Completed   1            9s

[root@master ~]# kubectl get jobs.batch 
NAME    COMPLETIONS   DURATION   AGE
myjob   1/1           8s         12s

# 删除Job控制器
[root@master ~]# kubectl delete -f myjob.yaml 
job.batch "myjob" deleted

#pod控制器创建失败，任务会确保创建成功而重启，避免失败

Cronjob

#类似ansible中的crontab模块，可以定时执行某一任务

四、StatefulSet

配置后端服务

# 为 Deploy 模板添加资源配额
[root@master ~]# cat mydeploy.yaml websvc.yaml >mycluster.yaml
[root@master ~]# vim mycluster.yaml 
---
kind: Deployment
apiVersion: apps/v1
metadata:
  name: mydeploy
spec:
  replicas: 1
  selector:
    matchLabels:
      app: deploy-httpd
  template:
    metadata:
      labels:
        app: deploy-httpd
    spec:
      containers:
      - name: apache
        image: myos:httpd
        resources:           # 为该资源设置配额
          requests:          # HPA 控制器会根据配额使用情况伸缩集群
            cpu: 300m        # CPU 配额

---
kind: Service
apiVersion: v1
metadata:
  name: websvc
spec:
  type: ClusterIP
  clusterIP: 10.245.1.80
  selector:
    app: deploy-httpd
  ports:
  - protocol: TCP
    port: 80
    targetPort: 80

[root@master ~]# kubectl replace --force -f mycluster.yaml
deployment.apps/mydeploy replaced
service/websvc replaced

# 验证服务
[root@master ~]# kubectl top pods
NAME                       CPU(cores)   MEMORY(bytes)   
mydeploy-b4f9dc786-w4x2z   6m           18Mi            

[root@master ~]# curl -s http://10.245.1.80/info.php
<pre>
Array
(
    [REMOTE_ADDR] => 10.244.219.64
    [REQUEST_METHOD] => GET
    [HTTP_USER_AGENT] => curl/7.61.1
    [REQUEST_URI] => /info.php
)
php_host:   mydeploy-b4f9dc786-w4x2z
1229