Updated on 2022-12-30 GMT+08:00

Configuring an Image Pull Policy

When a workload is created, the container image is pulled from the image repository to the node. The image is also pulled when the workload is restarted or upgraded.

By default, imagePullPolicy is set to IfNotPresent, indicating that if the image exists on the node, the existing image is used. If the image does not exist on the node, the image is pulled from the image repository.

The image pull policy can also be set to Always, indicating that the image is pulled from the image repository and overwrites the image on the node regardless of whether the image exists on the node.

apiVersion: v1
kind: Pod 
metadata:
  name: nginx 
spec: 
  containers:
  - image: nginx:alpine 
    name: container-0 
    resources:
      limits:
        cpu: 100m
        memory: 200Mi
      requests:
        cpu: 100m
        memory: 200Mi
    imagePullPolicy: Always
  imagePullSecrets:                 
  - name: default-secret

You can also set the image pull policy when creating a workload on the CCE console. As shown in the following figure, if you select Always, the image is always pulled. If you do not select it, the policy will be IfNotPresent, which means that the image is not pulled.

You are advised to use a new tag each time you create an image. If you do not update the tag but only update the image, when Pull Policy is set to IfNotPresent, CCE considers that an image with the tag already exists on the current node and will not pull the image again.