How to ensure that the old version of my docker image (part of GreenGrass component) is removed on updating the GreenGrass component (V2)

Please make sure you're using Greengrass Nucleus v2.10.2 as 2.10 will now delete unused images. They are only deleted after an additional deployment. ie deployment 1 puts them on device, 2 makes them unnecessary, then in deployment 3 they're removed.

Can you please explain the process to get this to work. I have created 3 deployments with 3 incrementing tags for a docker image. on The 3rd deployment the original image still exists on the core device.

+1 to Phil's comment. I have also tried 3 subsequent deployments and none of the image got removed. Now 4 images are present on the device

Thank you for letting us know, we're looking into it.

Also make sure that the greengrass.log does not contain "Unexpected error".

Please try the latest v2.10.3 now. It will not remove images which are already dangling. It will only removing images going forward from now.