In AWS, the difference between detach and force detach for an EBS (Elastic Block Store) volume is related to how the volume is detached from an instance and the consequences if something goes wrong.
Detach Volume
"You need to detach an Amazon Elastic Block Store (Amazon EBS) volume from an instance before you can attach it to a different instance or delete it. Detaching a volume does not affect the data on the volume."
This is the standard way to detach an EBS volume from an EC2 instance.
It ensures that the volume is safely detached, ensuring no data corruption and that any ongoing operations (like file system writes) are completed before the detachment.
The detachment request is sent to the instance, and the system checks if the volume is being used properly. If the instance is actively writing to the volume or it's the root volume, it may prevent detaching until it's safe to do so.
If the volume is in use or if there's an issue with the instance, AWS may prevent detachment, ensuring data integrity.
Force Detach Volume
This option is used when the normal detachment process cannot be completed, usually because the EC2 instance is in an unresponsive state (e.g., it's stuck or terminated unexpectedly).
Force detaching the volume can bypass checks for active use, meaning it could potentially cause data loss or corruption if there are ongoing writes or operations happening on the volume.
It should be used as a last resort when you're unable to detach the volume using the standard method, such as when the instance is not responding or is in a "stuck" state.
Summary
Detach is a safe, standard operation that ensures data integrity.
Force Detach is a more aggressive action to forcibly remove the volume, which can lead to data corruption or loss if not used cautiously.
