I have a Hyper-V virtual machine with a chain of six checkpoints. I want to keep the VM exactly as it was at checkpoint 3 and remove checkpoints 4, 5, and 6. However, deleting a checkpoint appears to merge its differencing disk into the parent. Is there a way to remove the later checkpoints without merging their changes, or otherwise make checkpoint 3 the VM's current disk state?
3 Answers
A checkpoint is represented by a differencing disk, so deleting it necessarily commits its blocks into the parent disk or checkpoint. There isn’t a normal Hyper-V operation that simply removes a checkpoint and discards its disk changes. If you want checkpoint 3 to be the final state, apply or revert to checkpoint 3, then remove the remaining checkpoints. Any changes made after checkpoint 3 will be discarded or consolidated as part of that process.
To make checkpoint 3 the VM’s current state, revert or apply the VM to checkpoint 3 and then delete the other checkpoints shown in Hyper-V Manager. Hyper-V will clean up the differencing disks by merging them; it does not provide a separate ‘delete without merging’ option.
If you need to preserve checkpoint 3 as an independent VM while leaving the original checkpoint tree untouched, export checkpoint 3 as a new virtual machine and start the exported copy. Verify that it works, then shut down and remove the original VM and its checkpoints when you’re certain you no longer need them.
Deleting checkpoints 4 through 6 does not preserve them separately; their disk changes are consolidated according to the checkpoint chain. The important distinction is that applying a checkpoint changes the disk state—it does not merely select a label without modifying the storage structure.