Pod has always been in ImagePullBackOff, but docker images to view the image still exist.
At this time, you need to pay attention to whether your Pod and mirror are on the same server.
Use kubectl get pods -A -o wide to view
Because the mirror does not exist on my 190 machine, it is always in this state. You can download the corresponding mirror on 190 to get it.
There are other reasons, for example, your image is indeed not downloaded, the version number is wrong, refer to the following article to see.
https://gardener.cloud/050-tutorials/content/howto/missing-registry-permission/
