k8s之控制器(工作负载)

k8s-控制器

k8s中控制器分为：deployment、DaemonSet、StatufluSet

使用控制器是为了用来管理pod

控制器通过标签来识别pod

1、Deployment:一般用来部署长期运行的、无状态的应用
特点：集群之中，随机部署

2、DaemonSet：每一个节点上部署一个Pod，删除节点自动删除对应的POD（zabbix-agent）
特点：每一台上有且只有一台

3、StatudfluSet: 部署有状态应用
特点：有启动顺序

#查看控制器版本
[root@k8s-master-01 ~]# kubectl explain deployment
KIND:     Deployment
VERSION:  apps/v1

1、Deploymnet

1.1、在配置清单中调用Deployment控制器

########控制器########
apiVersion: apps/v1
kind: Deployment
metadata:
  name: deployment
spec:
  replicas: 1
  selector:
    matchLabels:
      ddff: qln
  template:
########描述所需的状态########
    metadata:
      labels:
        ddff: qln
    spec:
      containers:
        - name: nginx
          image: nginx:1.18.0

#实例

#启动pod
[root@k8s-master-01 ~]# kubectl apply -f tag.yaml 
deployment.apps/deployment created

#查看pod
[root@k8s-master-01 ~]# kubectl get pod
NAME                         READY   STATUS    RESTARTS   AGE
deployment-98dbf6f45-gzp7l   1/1     Running   0          18s

#删除pod
[root@k8s-master-01 ~]# kubectl delete pod deployment-98dbf6f45-gzp7l
pod "deployment-98dbf6f45-gzp7l" deleted

#再次查看，发现控制器又创建了一个新的pod
[root@k8s-master-01 ~]# kubectl get pod
NAME                         READY   STATUS    RESTARTS   AGE
deployment-98dbf6f45-97w5k   1/1     Running   0          10s

1.2、弹性扩容

1、修改配置清单
[root@k8s-master-01 ~]# kubectl edit deployments.apps deployment
修改  replicas: 2  参数

2、打标签
[root@k8s-master-01 ~]# kubectl patch deployments.apps deployment -p '{"spec":{"replicas":4}}'

3、scale
[root@k8s-master-01 ~]# kubectl scale deployment/deployment --replicas=1

1.3、更新

1、打标签
[root@k8s-master-01 ~]# kubectl patch deployments.apps deployment -p '{"spec":{"template":{"spec":{"containers":[{"image":"nginx:1.17.0", "name":"nginx"}]}}}}'

2、修改配置清单

3、设置镜像
[root@k8s-master-01 ~]# kubectl set image deployment/deployment nginx=nginx:1.16.0

4、edit
[root@k8s-master-01 ~]# kubectl edit deployments.apps deployment

1.4、回滚

# 查看历史版本
kubectl rollout history [资源类型] [资源名]
[root@k8s-master-01 ~]# kubectl rollout history deployment deployment 
deployment.apps/deployment 
REVISION  CHANGE-CAUSE
2         <none>
3         <none>
4         <none>

#回滚到上个版本
kubectl rollout undo [资源类型] [资源名]
[root@k8s-master-01 ~]# kubectl rollout undo deployment deployment

#回滚到指定历史版本
[root@k8s-master-01 ~]# kubectl rollout history deployment deployment 
deployment.apps/deployment 
REVISION  CHANGE-CAUSE
2         <none>
4         <none>
5         <none>

[root@k8s-master-01 ~]# 
[root@k8s-master-01 ~]# kubectl rollout undo deployment deployment --to-revision=4
deployment.apps/deployment rolled back

2、DaemonSet

2.1、在配置清单中调用DaemonSet 控制器

apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: zabbix-agent
spec:
  selector:
    matchLabels:
      app: zabbix-agent
  template:
    metadata:
      labels:
        app: zabbix-agent
    spec:
      containers:
        - name: zabbix-agent
          image: zabbix/zabbix-agent:5.2.6-centos

2.2、更新

1、修改配置文件
[root@k8s-m-01 ~]# kubectl edit daemonsets.apps zabbix-agent 
daemonset.apps/zabbix-agent edited

2、打标签的方式
[root@k8s-m-01 ~]# kubectl patch daemonsets.apps zabbix-agent  -p '{"spec":{"template":{"spec":{"containers":[{"image":"zabbix/zabbix-agent:centos-5.2.4", "name":"zabbix-agent"}]}}}}'
daemonset.apps/zabbix-agent patched

3、设置镜像
[root@k8s-m-01 ~]# kubectl set image daemonset/zabbix-agent zabbix-agent=zabbix/zabbix-agent:centos-5.2.3
daemonset.apps/zabbix-agent image updated

2.3、回滚

# 回滚到上一个版本
[root@k8s-m-01 ~]# kubectl rollout undo daemonset zabbix-agent 
daemonset.apps/zabbix-agent rolled back

# 回滚到指定版本
[root@k8s-m-01 ~]# kubectl rollout undo daemonset zabbix-agent --to-revision=1
daemonset.apps/zabbix-agent rolled back