k8s高级_调度器Deployment

一: 简介

为啥需要deployment:

目的是让Kubernetes去管理一组无状态Pod的副本，也就是副本集，这样就能够保证一定数量的副本一直可用 ，不会因为某一个Pod挂掉导致整个服务挂掉。避免单点故障和支撑更高的访问量

概念：

Deployment是一个定义及管理多副本应用（即多个副本 Pod）的新一代对象，与Replication Controller相比，它提供了更加完善的功能，使用起来更加简单方便

二: 示例

1.0 定义deployment

bash 复制代码

 mkdir 11deployment ;  cd 11deployment

定义deployment

bash 复制代码

 vim  deployment.yaml
 
 
apiVersion: apps/v1
kind: Deployment    
metadata:
 name: nginx-deployment
spec:
 selector:           #选择器匹配要管理的Pod
   matchLabels:      
     app: nginx    
     
 replicas: 2         #Pod 副本数如果 Pod 少于 2 个（比如一个挂了），会自动创建新的补足；如果多于 2 个，会终止多余的。
 template:           #POD模板。以前定义Pod配置
   metadata:
     labels:
       app: nginx
   spec:
     containers:     #容器配置
     - name: nginx
       image: nginx
       ports:
       - containerPort: 80

2.0 创建deployment

创建deployment

bash 复制代码

[root@k8s-master 11deployment]#  kubectl apply -f deployment.yaml
deployment.apps/nginx-deployment created
[root@k8s-master 11deployment]#

3.0 查看

查看deployment

bash 复制代码

[root@k8s-master 11deployment]# kubectl get deployments
NAME               READY   UP-TO-DATE   AVAILABLE   AGE
nginx-deployment   2/2     2            2           13s
[root@k8s-master 11deployment]#

查看pod

bash 复制代码

[root@k8s-master 11deployment]# kubectl get pods -l app=nginx
NAME                                READY   STATUS    RESTARTS   AGE
nginx-deployment-7848d4b86f-j2867   1/1     Running   0          31s
nginx-deployment-7848d4b86f-r8rww   1/1     Running   0          31s
[root@k8s-master 11deployment]#

4.0 删除

bash 复制代码

[root@k8s-master 11deployment]# kubectl delete -f deployment.yaml 
deployment.apps "nginx-deployment" deleted
[root@k8s-master 11deployment]# kubectl get deployments
No resources found in default namespace.
[root@k8s-master 11deployment]#