k8s入门-Replica Sets控制器

Bertha 。 2023-02-12 14:27 28阅读 0赞

ReplicaSet是下一代Replication Controller。 现在，ReplicaSet和Replication Controller之间的唯一区别是selector支持。 ReplicaSet支持标签用户指南中描述的新的基于集合的选择器要求，而Replication Controller仅支持基于等级的选择器要求。

在开始之前，删除之前创建的RC

[root@k8s-01 ~]# kubectl delete rc nginx-rc 
    replicationcontroller "nginx-rc" deleted

编写RS的YAML文件

[root@k8s-01 ~]# cat nginx-rs.yaml 
    apiVersion: apps/v1
    kind: ReplicaSet
    metadata:
      name: nginx-rs
      labels:
        app: nginx
    spec:
      replicas: 3
      selector:
        matchLabels:
          app: nginx
      template:
        metadata:
          labels:
            app: nginx
        spec:
          containers:
          - name: nginx
            image: nginx
            ports:
            - containerPort: 80

这是一个`ReplicaSet`类型的。

创建RS

[root@k8s-01 ~]# kubectl create -f nginx-rs.yaml 
    replicaset.apps/nginx-rs created

查看RS

[root@k8s-01 ~]# kubectl get rs nginx-rs
    NAME       DESIRED   CURRENT   READY   AGE
    nginx-rs   3         3         3       29s

查看Pod

[root@k8s-01 ~]# kubectl get pod
    NAME                        READY   STATUS    RESTARTS   AGE
    nginx-rs-g9chx              1/1     Running   0          59s
    nginx-rs-h6f7k              1/1     Running   0          59s
    nginx-rs-lwcbf              1/1     Running   0          59s

扩容和缩容

[root@k8s-01 ~]# kubectl scale rs nginx-rs --replicas=2 
    replicaset.apps/nginx-rs scaled
    
    [root@k8s-01 ~]# kubectl get pod
    NAME                        READY   STATUS    RESTARTS   AGE
    nginx-rs-g9chx              1/1     Running   0          10m
    nginx-rs-h6f7k              1/1     Running   0          10m
    
    [root@k8s-01 ~]# kubectl get rs
    NAME                  DESIRED   CURRENT   READY   AGE
    nginx-rs              2         2         2       10m
    
    
    [root@k8s-01 ~]# kubectl scale rs nginx-rs --replicas=4 
    replicaset.apps/nginx-rs scaled
    
    [root@k8s-01 ~]# kubectl get pod
    NAME                        READY   STATUS              RESTARTS   AGE
    nginx-rs-g9chx              1/1     Running             0          10m
    nginx-rs-ghz7l              1/1     Running             0          7s
    nginx-rs-h6f7k              1/1     Running             0          10m
    nginx-rs-j5d4p              0/1     ContainerCreating   0          7s
    
    [root@k8s-01 ~]# kubectl get rs
    NAME                  DESIRED   CURRENT   READY   AGE
    nginx-rs              4         4         4       11m

参考文章：  
[http://k8s.unixhot.com/kubernetes/rs.html][http_k8s.unixhot.com_kubernetes_rs.html]

[http_k8s.unixhot.com_kubernetes_rs.html]: http://k8s.unixhot.com/kubernetes/rs.html