vdi parent + differential problem

[baracus]

hi
i get the following error message for a vdi
i tried to replace a differential vdi for parent vdi to free disk space
i changed the uuid but that still didnt work so i set it back to as it was (parent + differentiell)

ERROR MESSAGE:

Code: Select all

Parent UUID {00000000-0000-0000-0000-000000000000} of the medium 'M:\vpc\VirtualBox VMs\xp\Snapshots\{c861209a-

0fe6-4c4a-b68f-a1247b783a25}.vdi' does not match UUID {d43f78bd-5c06-4371-b657-dcb9737bc05a} of its parent medium 

stored in the media registry ('C:\Users\jk/.VirtualBox\VirtualBox.xml').
Fehlercode:
E_FAIL (0x80004005)
Komponente:
MediumWrap
Interface:
IMedium {4afe423b-43e0-e9d0-82e8-ceb307940dda}

XML FILE:

Code: Select all

<?xml version="1.0"?>

<!-- ** DO NOT EDIT THIS FILE. ** If you make changes to this file while any VirtualBox related application ** is 

running, your changes will be overwritten later, without taking effect. ** Use VBoxManage or the VirtualBox 

Manager GUI to make changes. -->

-<VirtualBox version="1.12-windows" xmlns="http://www.innotek.de/VirtualBox-settings">


-<Global>


-<ExtraData>

<ExtraDataItem value="general,system,preview,display,storage,audio,network,usb,sharedFolders,description" 

name="GUI/DetailsPageBoxes"/>

<ExtraDataItem value="m=41f05857-b01c-4c2d-b4c0-c06b4888feb6,m=ebed2e37-ab57-433f-a260-024595158df8,m=82d571ae-

01a9-46b2-8240-6cc9b07ecbe9,m=58e212b0-3916-47e6-b942-2ef2814c8647,m=194c6c88-d280-4fd0-b655-

d4f4af77ae87,m=8e6f96c3-a639-4f61-9a15-ee1e598a9c51" name="GUI/GroupDefinitions/"/>

<ExtraDataItem value="NewVM" name="GUI/HideDescriptionForWizards"/>

<ExtraDataItem value="m=xp" name="GUI/LastItemSelected"/>

<ExtraDataItem value="716,375,925,656" name="GUI/LastWindowPosition"/>

<ExtraDataItem value="M:/vpc/VirtualBox VMs/xp" name="GUI/RecentFolderCD"/>

<ExtraDataItem value="M:/vpc/VirtualBox VMs/xp/Snapshots" name="GUI/RecentFolderHD"/>

<ExtraDataItem value="M:\vpc\VirtualBox VMs\xp\xp.vdi" name="GUI/RecentListCD"/>

<ExtraDataItem value="M:\vpc\VirtualBox VMs\xp\Snapshots\{c861209a-0fe6-4c4a-b68f-a1247b783a25}.vdi,M:\vpc

\VirtualBox VMs\xp\xp.vdi,M:\vpc\VirtualBox VMs\jk\jk.vdi,M:\vpc\HD_vbox\98.vdi" name="GUI/RecentListHD"/>

<ExtraDataItem value="307,614" name="GUI/SplitterSizes"/>

<ExtraDataItem 

value="remindAboutMouseIntegration,remindAboutAutoCapture,confirmInputCapture,warnAboutInaccessibleMedia,remindAbo

utWrongColorDepth" name="GUI/SuppressMessages"/>

<ExtraDataItem value="8" name="GUI/UpdateCheckCount"/>

<ExtraDataItem value="1 d, 2015-12-01, stable, 5.0.6" name="GUI/UpdateDate"/>

</ExtraData>


+<MachineRegistry>
<MachineEntry src="C:\Users\jk\VirtualBox VMs\xp\xp.vbox" uuid="{41f05857-b01c-4c2d-b4c0-c06b4888feb6}"/>

<MachineEntry src="C:\Users\jk\VirtualBox VMs\98\98.vbox" uuid="{ebed2e37-ab57-433f-a260-024595158df8}"/>

<MachineEntry src="C:\Users\jk\VirtualBox VMs\95\95.vbox" uuid="{82d571ae-01a9-46b2-8240-6cc9b07ecbe9}"/>

<MachineEntry src="M:/vpc/VirtualBox VMs/xp/xp.vbox" uuid="{58e212b0-3916-47e6-b942-2ef2814c8647}"/>


-<MediaRegistry>

<HardDisks/>

<DVDImages/>

<FloppyImages/>

</MediaRegistry>

[mpack]

Your topic could be renamed "A Quick Tutorial on how to Destroy a VM", starting with the decision to use snapshots, then deciding to use the host OS to delete a snapshot element because snapshots eat lots of disk space, and then the decision to mess with the UUIDs without understanding their purpose.

I expect that this mess is now fatal. You have NOT restored the UUID to its original value, or you would not still be getting the error message. Nothing can really be done until you restore the missing data. Is it too much to hope that you made a backup of the VM before attempting major surgery? Yes, I know, that's a ridiculous suggestion.

How exactly did you "change the UUID"?

[baracus]

no need to tell me that i am not an expert , i am not by any means, still i can ask a question thats what a user forum is for ..........

also ...i checked the uuid's BEFOREHAND in the manager for virtual media, THEN changed them
with the command :
VBoxManage internalcommands sethduuid

i changed them back to what they were exactly

but...
in the error message it says the original uuid is in the xml (need to matched) while ACTUALLY theres a new random uuid in the xml file for that vdi
also if i change it to the old one it changes the uuid to 00000000000000000000 as you can see in the error message
i can set a random new uuid ,and change that one in the xml too, but its not recognized correctly since the program always insists the old one is stated in the xml, so ....
1.
where in the xml file do you change the uuid ?
2.
is it in any way possible to start a differential WITHOUT its parent?

[mpack]

1. where in the xml file do you change the uuid ?

Nowhere. The UUID is stored in the VDI header, it is only referenced by the xml. And anyway I think that error message is misleading - the global media registry is no longer physically stored in VirtualBox.xml or anywhere else. It is constructed at runtime from the local media registries in each .vbox file. An actual media registry in VirtualBox.xml was abandoned years ago (v4.0.0).

2. is it in any way possible to start a differential WITHOUT its parent?

You can hack the VDI headers together yes (using a hex editor) to work around the error - but that doesn't recover the data that was lost. Nothing can do that except a backup. Hence the practicality of repair will depend greatly on how important the lost data was.

A snapshot chain goes <base vdi>+A+B+C+D etc. Which of these did you delete? And confirm that you did this in the host OS?