3.k8s资源控制器rs Deployment Job

k8s资源控制器

#控制器类型

ReplicaSet    #rs,确保pod副本数,rs已替代rc
Deployment    #管理rs,升级、回滚、扩容pod
DaemonSet     #在每个节点运行一个Pod
StateFulSet   #解决有状态服务,Pod重新调度后PodName和HostName不变
Job/CronJob   #批处理任务/定时任务
HPA #按CPU使用率或自定义metrics扩展Pod数量 Horizontal Pod Autoscaling

#rs实例

#rs-demo.yaml
apiVersion: extensions/v1beta1
kind: ReplicaSet
metadata:
 name: rs-demo
spec:
 replicas: 2	#副本数量
 selector:
   matchLabels:
     app: nginx
 template:
   metadata:
     labels:
       app: nginx
   spec:
     containers:
     - name: nginx-rs
       image: alivv/nginx:node
       ports:
       - containerPort: 80

#创建
kubectl create -f rs-demo.yaml

#查看rs
kubectl get rs
kubectl describe rs rs-demo

#查看pod
kubectl get pod
kubectl get pod --show-labels

#删除所有pod
kubectl delete pod --all
#再次查看，发现pod存在，保持在副本数量
kubectl get pod

#删除
kubectl delete -f rs-demo.yaml

#Deployment实例

Deployment -> 创建ReplicaSet(rs) -> 创建Pod

#nginx-deployment.yaml
apiVersion: apps/v1beta1
kind: Deployment
metadata:
  name: nginx-deploy
  labels:
    app: nginx-demo
spec:
  replicas: 3
  template:
    metadata:
      labels:
        app: nginx
    spec:
      containers:
      - name: nginx
        image: alivv/nginx:node
        ports:
        - containerPort: 80

#创建( --record参数记录命令,方便后续查看变化)
kubectl apply -f nginx-deployment.yaml --record

#查看
kubectl get deployments
kubectl get rs
kubectl get pod --show-labels

#扩容
kubectl scale deployment nginx-deploy --replicas 5

#Deployment自动扩展
#kubectl autoscale deployment nginx-deployment --min=3 --max=9 --cpu-percent=80

#更新镜像
kubectl set image deployment/nginx-deploy nginx=nginx:alpine

#回滚到前一个版本
kubectl rollout undo deployment/nginx-deploy
#查看回滚状态(回滚完成返回值为0 echo $?)
kubectl rollout status deployment/nginx-deploy
#查看历史rs
kubectl get rs
#查看回滚历史
kubectl rollout history deployment nginx-deploy

#回滚到指定版本
#kubectl rollout undo deployment nginx-deploy --to-revision=2

#生产建议设置Deployment的.spec.revisionHistoryLimit限制保留revision历史记录数量

Deployment更多参数 https://www.kubernetes.org.cn/deployment

#DaemonSet实例

#nginx-ds.yaml
kind: DaemonSet
apiVersion: apps/v1
metadata:
 name: deamonset-example
 labels:
   app: daemonset
spec:
 selector:
   matchLabels:
     name: deamonset-example
 template:
   metadata:
     labels:
       name: deamonset-example
   spec:
     containers:
     - name: nginx
       image: alivv/nginx:node

#部署
kubectl create -f nginx-ds.yaml

#查看启动node
kubectl get pods -o wide

#删除
kubectl delete -f nginx-ds.yaml

#Job实例

可选参数

RestartPolicy 仅支持Never或OnFailure

spec.completions 需要成功运行Pod个数，默认1

spec.parallelism 运行Pod个数，默认1

spec.activeDeadlineSeconds 失败Pod重试最大时间

#job-demo.yaml
apiVersion: batch/v1
kind: Job
metadata:
  name: job-demo
spec:
  template:
    metadata:
      name: job-demo
    spec:
      restartPolicy: Never
      containers:
      - name: job-test
        image: busybox
        command: ["bin/sh", "-c", "for n in $(seq 1 9);do echo $n;done"]

#创建
kubectl create -f job-demo.yaml

#查看
kubectl get job
kubectl get pod
kubectl log $(kubectl get pod |awk '/job-demo/{print $1}')

#删除
kubectl delete -f job-demo.yaml

#cronjob实例

cronjob -> 创建job -> 创建Pod

schedule: "* * * * *" 分 时 日 月 周，相当于Linux定时任务

.spec.startingDeadlineSeconds 启动Job期限，默认没限制

.spec.successfulJobsHistoryLimit 保留完成job数，默认3

.spec.failedJobsHistoryLimit 保留失败job数，默认1

.spec.concurrencyPolicy 并发策略，默认Allow，Forbid禁止，Replace关闭旧的运行新Job

#cronjob-demo.yaml
kind: CronJob
apiVersion: batch/v1beta1
metadata:
  name: cronjob-demo
spec:
  schedule: "*/1 * * * *"  #每分钟执行
  jobTemplate:
    spec:
      template:
        spec:
          restartPolicy: OnFailure
          containers:
          - name: cronjob-demo
            image: busybox
            args:
            - /bin/sh
            - -c
            - echo -n $(hostname) 'cronjob demo ';date +%T

#创建
kubectl create -f cronjob-demo.yaml

#查看
kubectl get cronjob

kubectl get job
kubectl get pod
kubectl get pod |awk '/cronjob-demo/{print "kubectl logs "$1}' |bash

#删除
kubectl delete -f cronjob-demo.yaml

---

Blog地址 https://www.cnblogs.com/elvi/p/11755712.html

本文git地址 https://gitee.com/almi/k8s/tree/master/notes