How To Resolve ImagePullBackOff Errors

Background

An ImagePullBackOff error indicates a persistent problem that needs to be addressed. After repeated ErrImagePull errors, where the kubelet tried but failed several times to successfully pull a container image, an ImagePullBackOff error is thrown and another image download attempt is scheduled.

Solution

Try the following to resolve ImagePullBackOff errors:

• Restart the Pod: Restarting the pod can sometimes resolve the issue.

• Verify the image name and tag: Ensure that the correct image name and tag are specified in the container configuration, including the correct case with any necessary slashes and the correct registry and repository name. The Events section of the describe pod output might contain the following messages if the image name, tag, registry, or repository is the issue:

  • manifest for <name:tag>... not found

  • repository <name> not found: does not exist or no pull access

• Verify image availability: Verify that the specified image exists in the specified repository, that it is up-to-date, and that it can be pulled using the command line or a web browser.

• Check authentication: If the registry that contains the image requires authentication, ensure that you have provided the correct credentials. The Events section of the describe pod output will contain the following message if this is the issue:

  • authorization failed

• Verify network connectivity: Verify that there is a stable network connection between the host and the registry where the image is stored.

• Increase the Pull Policy: If the error persists, try changing the imagePullPolicy from Always to IfNotPresent.

These are general steps that can help resolve the ImagePullBackOff error. However, the exact solution may vary depending on the specific situation and the cause of the error.