Replicaset doesnot update pods in when pod image is modified

Question

I have created a replicaset with wrong container image with below configuration.

apiVersion: extensions/v1beta1
kind: ReplicaSet
metadata:
  name: rs-d33393
  namespace: default
spec:
  replicas: 4
  selector:
    matchLabels:
      name: busybox-pod
  template:
    metadata:
      labels:
        name: busybox-pod
    spec:
      containers:
      - command:
        - sh
        - -c
        - echo Hello Kubernetes! && sleep 3600
        image: busyboxXXXXXXX
        name: busybox-container

Pods Information:

$ kubectl get pods
NAME              READY     STATUS             RESTARTS   AGE
rs-d33393-5hnfx   0/1       InvalidImageName   0          11m
rs-d33393-5rt5m   0/1       InvalidImageName   0          11m
rs-d33393-ngw78   0/1       InvalidImageName   0          11m
rs-d33393-vnpdh   0/1       InvalidImageName   0          11m

After this, i try to edit the image inside replicaset using kubectl edit replicasets.extensions rs-d33393 and update image as busybox.

Now, i am expecting pods to be recreated with proper image as part of replicaset.

This has not been the exact result.

Can someone please explain, why it is so?

Thanks :)

Answer 1

您必须ReplicaSets直接杀死旧的 Pod，以便使用正确的映像创建新的 Pod。

如果您要使用Deployment，并且您应该使用 ，则更改图像将强制重新创建 Pod。

Answer 2

Replicaset不支持更新。只要存在与选择器标签匹配的所需数量的 Pod，复制集的工作就完成了。你应该改用Deployment。

https://kubernetes.io/docs/concepts/workloads/controllers/replicaset/

来自文档：

要以受控方式将 Pod 更新到新规范，请使用 Deployment，因为 ReplicaSet 不支持直接滚动更新。