Differencing Disks

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Cha0sEngine
Posts: 2
Joined: 12. Oct 2009, 18:26
Primary OS: MS Windows 7
VBox Version: OSE other
Guest OSses: XP

Differencing Disks

Post by Cha0sEngine »

Anyone tried using differencing disks?
(a forum search says yes, but perhaps not how i had hoped they would)

Im trying to boot an XP "virtual box".

I have a parent VHD and a child "differencing" disk based on that parent.

I am able to tick the "show differencing disks" box on the "Hard Disks" page, and i can select the disk i want to use.

But when i click OK, the details screen shows the parent is selected, not the child.
and booting the configuration shows that it is indeed the parent thats being booted.

any clues? is it a bug?

Cheers.
Sasquatch
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Posts: 17798
Joined: 17. Mar 2008, 13:41
Primary OS: Debian other
VBox Version: VirtualBox+Oracle ExtPack
Guest OSses: Windows XP, Windows 7, Linux
Location: /dev/random

Re: Differencing Disks

Post by Sasquatch »

The differencing disk feature in VB is like snapshots. The base VDI will still be booted, but the latest changes are in the differencing disk. So if you would save a file to the desktop, that one would be stored in the differencing one. When booting, the base VDI will be read, and at the same time the differencing to make sure the latest file 'version' is used.
Read the Forum Posting Guide before opening a topic.
VirtualBox FAQ: Check this before asking questions.
Online User Manual: A must read if you want to know what we're talking about.
Howto: Install Linux Guest Additions
Howto: Use Shared Folders on Linux Guest
See the Tutorials and FAQ section at the top of the Forum for more guides.
Try searching the forums first with Google and add the site filter for this forum.
E.g. install guest additions site:forums.virtualbox.org

Retired from this Forum since OSSO introduction.
Cha0sEngine
Posts: 2
Joined: 12. Oct 2009, 18:26
Primary OS: MS Windows 7
VBox Version: OSE other
Guest OSses: XP

Re: Differencing Disks

Post by Cha0sEngine »

hmmm... so you select the base disk, but VB will use the child to boot?
ill give it another go.
Sasquatch
Volunteer
Posts: 17798
Joined: 17. Mar 2008, 13:41
Primary OS: Debian other
VBox Version: VirtualBox+Oracle ExtPack
Guest OSses: Windows XP, Windows 7, Linux
Location: /dev/random

Re: Differencing Disks

Post by Sasquatch »

If the differencing disk is registered and set as the child of the base VDI, then yes, it will use that differencing disk too.
Read the Forum Posting Guide before opening a topic.
VirtualBox FAQ: Check this before asking questions.
Online User Manual: A must read if you want to know what we're talking about.
Howto: Install Linux Guest Additions
Howto: Use Shared Folders on Linux Guest
See the Tutorials and FAQ section at the top of the Forum for more guides.
Try searching the forums first with Google and add the site filter for this forum.
E.g. install guest additions site:forums.virtualbox.org

Retired from this Forum since OSSO introduction.
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