virtualbox.org

Hi,

I've read the parts of the manual regarding snapshots and differencing images, and I am still not sure about one thing: where are differencing images stored?

Suppose I have a simple VM with a VDI for its main hard disk. I know where the file storing the VDI is (I created it in a folder which is not the default one). And it's in normal mode.
Now I take a snapshot. I notice that a file has been created in ~/VirtualBox VMs/my_vm/snapshots
Somehow this file "is" the snapshot.
I understand that now my VDI stops growing, becomes kind of "read only" and all changes will be stored in a differencing image. Is the differencing image contained within the snapshot file? Or will a separate file be created for the differencing image? If so where? I haven't seen any other file be created apart from the snapshot file...

thanks
m.

Ok, I've realised the file created in the Snapshots folder is actually the differencing image.

So now my question is kind of vice versa. A snapshot is supposed to also contain a copy of the VM settings (i.e. the virtual hardware). Where is _this_ information stored? Is it stored within the vdi file as well, together with disk data??

The snapshots folder holds difference images. Referring to these files as snapshots is convenient shorthand but somewhat inaccurate. In reality a snapshot is a combination of disk state and control information: the .vbox file holds all the control info, including for the current state and for all snapshots.