virtualbox.org

I have a VM on hand that uses two disk images, which I want to repack[*] to reduce their on-disk size.

Data.vdi seems to be image base
Data_0.vdi reporting as "Dynamically allocated differencing storage"

I can only add the Data_0.vdi image if I add the Data.vdi first.
Now, I'd like to know how to correctly apply repack to them so to not destroy the setup completely.

* By "repack" I mean zeroing unused space on the partition and then using on prepared image.

If you're set on using that command, see this post on compacting a VDI: viewtopic.php?p=29272#p29272

If you want something easier, use Mpack's CloneVDI.

Either way, as far as I have read, only the differencing image can be shrunk. The base image cannot be changed.

I'm familiar with CloneVDI, thank you.