Mistakes will happen during deployment, and when they do, Helm makes it easy to undo, or “roll back” to the previously deployed version.
Open values.yaml and modify the image name under nodejs.image to brentley/ecsdemo-nodejs-non-existing. This image does not exist, so this will break our deployment.
Deploy the updated demo application chart:
helm upgrade workshop ~/environment/eksdemo
The rolling upgrade will begin by creating a new nodejs pod with the new image. The new ecsdemo-nodejs Pod should fail to pull non-existing image. Run helm status command to see the ImagePullBackOff error:
helm status workshop
Now we are going to rollback the application to the previous working release revision.
First, list Helm release revisions:
helm history workshop
Then, rollback to the previous application revision (can rollback to any revision too):
# rollback to the 1st revision
helm rollback workshop 1
Validate workshop release status with:
helm status workshop