Do updates to "parent" snapshot carry through to "children"

This is for discussing general topics about how to use VirtualBox.
Post Reply
vberic
Posts: 22
Joined: 27. Nov 2009, 18:00
Primary OS: openSUSE
VBox Version: VirtualBox+Oracle ExtPack
Guest OSses: XP SP3

Do updates to "parent" snapshot carry through to "children"

Post by vberic »

In this kind of situation:
Snapshot1 (say, basic Win7)
     -Child 1.1
     -Child 1.2
        -Child 1.2.1
If I restore and open Snapshot 1 and it gets updated by MS. I then create a new snapshot, so I now have:
Snapshot1 (say, basic Win7)
     -Child 1.1
     -Child 1.2
        -Child 1.2.1
Snapshot 2 (MS updates)
Is there any easy way to update the rest of my snapshot tree short of manually recreating each child and letting MS update it?

Thanks.
mpack
Site Moderator
Posts: 39134
Joined: 4. Sep 2008, 17:09
Primary OS: MS Windows 10
VBox Version: VirtualBox+Oracle ExtPack
Guest OSses: Mostly XP

Re: Do updates to "parent" snapshot carry through to "children"

Post by mpack »

No, that isn't the way snapshots work. Once a snapshot is created the parent image is frozen, and all further writes go to the current child. The whole point of a snapshot is the freeze effect. If you somehow managed to force a write to a parent then you will in effect have corrupted all the children at once.

The closest you can get would be if all the children can see the same virtual network server, which pushes updates out to them. This saves work, but is of course wasteful of disk space since each child stores its own copy of the update - not much can be done about that.
Post Reply