What is the difference disable an AMI vs deregister an AMI? Also what is the process of deleting a private ami in AWS?

Question

What is the difference disable an AMI vs deregister an AMI? Also what is the process of deleting a private ami in AWS? I had earlier created an image from instance, but now I want to delete the ami. I have already terminated the instance.

Answer 1

From Disable an AMI - Amazon Elastic Compute Cloud:

You can disable an AMI to prevent it from being used for instance launches. You can't launch new instances from a disabled AMI. You can re-enable a disabled AMI so that it can be used again for instance launches.

From Deregister your AMI - Amazon Elastic Compute Cloud:

You can deregister an AMI when you have finished using it. After you deregister an AMI, you can't use it to launch new instances.

When you deregister an AMI, it doesn't affect any instances that you've already launched from the AMI or any snapshots created during the AMI creation process. You'll continue to incur usage costs for these instances and storage costs for the snapshot. Therefore, you should terminate any instances and delete any snapshots that you're finished with.

Basically, 'deregistering' is akin to deleting it, while 'disabling' just makes it temporarily unavailable.

An AMI really consists of an Amazon EBS Snapshot plus additional metadata. Deleting the AMI won't necessarily throw away the underlying data that is stored in the Snapshot.