Each container in a Pod has a container image. Once you have created an image and pushed it to a registry, you can then refer to it in the Pod.

Image pull policy overview

When OpenShift Container Platform creates containers, it uses the container’s imagePullPolicy to determine if the image should be pulled prior to starting the container. There are three possible values for imagePullPolicy:

Table 1. imagePullPolicy values
Value Description

Always

Always pull the image.

IfNotPresent

Only pull the image if it does not already exist on the node.

Never

Never pull the image.

If a container’s imagePullPolicy parameter is not specified, OpenShift Container Platform sets it based on the image’s tag:

  1. If the tag is latest, OpenShift Container Platform defaults imagePullPolicy to Always.

  2. Otherwise, OpenShift Container Platform defaults imagePullPolicy to IfNotPresent.