virtualbox.org

Hi Experts,

I have been struggling in finding solution for my problem. Please help me.

Problem :
I am unable to open my VM now. It was fine before but now receiving below error.
Error Message:
A differencing image of snapshot {f8c4045b-e597-466b-852c-7926b8604cb4} could not be found. Could not find an open hard disk with UUID {e36644b1-8c85-4baa-b51b-37896d885ef7}.vmdk Result Code: E_FAIL (0x80004005)

Version: I am using VirtualBox 4.1.18. Oracle VM Linux 5

I am not finding above mentioned snapshort. I even tried to removed relevant containt from .vbox file but did not worked.
I also tried to create similar named file but still the same error.
I also searched for VBoxFixHDD tool to download but did not find it.
I also runned VBoxManager.exe list hdd & it seems all is normal.

C:\Program Files\Oracle\VirtualBox>VBoxManage.exe list hdds
UUID: b69a9f98-a028-404b-8a50-f377eb7e0a51
Parent UUID: base
Format: VMDK
Location: C:\Users\VirtualBox VMs\ovm3\OracleVMManager3-disk1.vmdk
State: created
Type: normal
Usage: ovm3 (UUID: ec0741ef-8aba-42b8-b43e-8965027115c7)

UUID: 3144513f-0e8c-40b9-8e17-090008bdf1b2
Parent UUID: base
Format: VMDK
Location: C:\Users\VirtualBox VMs\ovm3\OracleVMManager3-disk2.vmdk
State: created
Type: normal
Usage: ovm3 (UUID: ec0741ef-8aba-42b8-b43e-8965027115c7)

UUID: 4e485ef3-af58-4cfa-98da-2789eeb28145
Parent UUID: base
Format: VMDK
Location: C:\Users\VirtualBox VMs\ORACLE_LINUX_5_PLANHDD\ORACLE_LINUX_5_PLANHDD.vmdk
State: created
Type: normal

UUID: 9256c00b-6488-4cd2-808e-f2b5aa48dc19
Parent UUID: 4e485ef3-af58-4cfa-98da-2789eeb28145
Format: VMDK
Location: C:\Users\VirtualBox VMs\Oracle_Linux5\Snapshots\{9256c00b-6488-4cd2-808e-f2b5aa48dc19}.vmdk
State: created
Type: normal

UUID: 13e55c0d-f5f1-47b1-8ec3-da02523f08d3
Parent UUID: base
Format: VMDK
Location: C:\Users\VirtualBox VMs\Oracle_Linux5\Oracle_Linux5.vmdk
State: created
Type: normal

UUID: fdf931fa-d76b-4f78-9b5c-711d646c30ee
Parent UUID: 13e55c0d-f5f1-47b1-8ec3-da02523f08d3
Format: VMDK
Location: C:\Users\VirtualBox VMs\Oracle_Linux5\Snapshots/{fdf931fa-d76b-4f78-9b5c-711d646c30ee}.vmdk
State: created
Type: normal

UUID: 45fb3dc7-db83-42f0-a627-025ce060b56e
Parent UUID: fdf931fa-d76b-4f78-9b5c-711d646c30ee
Format: VMDK
Location: C:\Users\VirtualBox VMs\Oracle_Linux5\Snapshots/{45fb3dc7-db83-42f0-a627-025ce060b56e}.vmdk
State: created
Type: normal

UUID: a75043ef-a3cb-4860-80cf-758970e2b279
Parent UUID: 45fb3dc7-db83-42f0-a627-025ce060b56e
Format: VMDK
Location: C:\Users\VirtualBox VMs\Oracle_Linux5\Snapshots/{a75043ef-a3cb-4860-80cf-758970e2b279}.vmdk
State: created
Type: normal

Please read the following carefully and provide each of the following :-

A directory listing (text or good quality screenshot) of <VM folder>.
A directory listing (text or good quality screenshot) of <VM folder>/Snapshots.
A zipped copy of the .vbox file - ideally one not already modified by you.


And what did you do to trigger this error? Did you delete a file on the host? Did you use the UI to a delete a snapshot?

And just out of curiosity - why are you using VMDKs?

Hi Mpack,
Thanks a lot for the quick response.Inline my responses.

A directory listing (text or good quality screenshot) of <VM folder>.
Vimal: PFA OracleVM_Issue.jpg,VirtualBoxVMs.zip

A directory listing (text or good quality screenshot) of <VM folder>/Snapshots.
Vimal: PFA VirtualBoxVMs.zip

A zipped copy of the .vbox file - ideally one not already modified by you.
Vimal: PFA VirtualBoxVMs.zip

And what did you do to trigger this error? Did you delete a file on the host? Did you use the UI to a delete a snapshot?
Vimal : I had 6-7 snapshot hence I deleted two snapshot from the middle using VBox UI & was working on the current snapshot. After EOD I have shut down the VM but next day when I try to open was getting this error.

And just out of curiosity - why are you using VMDKs?
Vimal: I am using VMDKs as I think fixed size gives better performance as there is no overhead involved in dynamic increasing the size.

Help Appreciated.

IgnitedMind wrote:Thanks a lot for the quick response.Inline my responses.

Thanks. I had a look at the .vbox file, and it looks like VirtualBox must have completed a merge of part of the middle of the VMDK snapshot chain, discarding one or two intemediate snapshot files. The intermediate files have been removed from the local media registry and deleted from the Snapshots folder, but the corresponding snapshot control information is still present and wants to find the deleted files, hence the error. The control file is a spaghetti mess of snapshot info, so I'm not going to attempt a repair on that.

VDI users could just use CloneVDI to recover this, but you chose VMDK so that easy out is scuppered. A recovery method I've advised before, and which has worked before is: remove the VM from the UI, making sure to keep the physical files, then shut down VirtualBox and leave it for 30 seconds. Then run VirtualBox again, create a new (dummy) VM. Details will not matter as you will never run this VM. To this VM you need to mount every vmdk file you see in the <VMname> and <VMname>/Snapshots folder. The idea is simply to get each disk fragment registered in the media registry, which will allow clonehd to work. Hence you then shut down VirtualBox again and type
This should result in a cloned hard disk, in VDI format, which is a merge of the entire snapshot chain, and which you can proceed to build a new VM around.

I suggest you avoid snapshots in future.

IgnitedMind wrote:

mpack wrote:And just out of curiosity - why are you using VMDKs?

Vimal: I am using VMDKs as I think fixed size gives better performance as there is no overhead involved in dynamic increasing the size.

I'm afraid that makes no sense. First, there is no measurable overhead for "dynamic" beyond the first couple of days (rapid expansion phase), and even then the overhead is nothing much - and secondly you were making heavy use of snapshots, which are inherently dynamic anyway, in fact far more so than an ordinary dynamic disk.

Thanks Mpack for the valuable suggestion.
"snapshot control information is still present", could you mind telling me where i can see control file ?

If i do not use snapshort than how am i going to keep my backup in future

I have done very similer workaround yesterday till i get solution to my existing error. My workaround solution which worked for me is as follow. (new disk named "test1.vmdk")

c:\Program Files\Oracle\VirtualBox>VBoxManage.exe clonehd "C:\Users\Serene\VirtualBox VMs\Oracle_Linux5\Oracle_Linux5.vmdk" "f:\test1.vmdk"
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%
Clone hard disk created in format 'VMDK'. UUID: 4a74e2e0-626f-4462-939b-e0be8e358c7a

c:\Program Files\Oracle\VirtualBox>VBoxManage.exe clonehd "C:\Users\Serene\VirtualBox VMs\Oracle_Linux5\Snapshots/{fdf931fa-d76b-4f78-9b5c-711d646c30ee}.vmdk" "f:\test1.vmdk" --existing
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%
Clone hard disk created in format 'VMDK'. UUID: 4a74e2e0-626f-4462-939b-e0be8e358c7a

c:\Program Files\Oracle\VirtualBox>VBoxManage.exe clonehd "C:\Users\Serene\VirtualBox VMs\Oracle_Linux5\Snapshots/{45fb3dc7-db83-42f0-a627-025ce060b56e}.vmdk" "f:\test1.vmdk" --existing
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%
Clone hard disk created in format 'VMDK'. UUID: 4a74e2e0-626f-4462-939b-e0be8e358c7a

c:\Program Files\Oracle\VirtualBox>VBoxManage.exe clonehd "C:\Users\Serene\VirtualBox VMs\Oracle_Linux5\Snapshots/{a75043ef-a3cb-4860-80cf-758970e2b279}.vmdk" "f:\test1.vmdk" --existing
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%
Clone hard disk created in format 'VMDK'. UUID: 4a74e2e0-626f-4462-939b-e0be8e358c7a

c:\Program Files\Oracle\VirtualBox>VBoxManage.exe clonehd "C:\Users\Serene\VirtualBox VMs\Oracle_Linux5\Snapshots/{9256c00b-6488-4cd2-808e-f2b5aa48dc19}.vmdk" "f:\test1.vmdk" --existing
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%
Clone hard disk created in format 'VMDK'. UUID: 4a74e2e0-626f-4462-939b-e0be8e358c7a

c:\Program Files\Oracle\VirtualBox>VBoxManage.exe clonehd "C:\Users\Serene\VirtualBox VMs\Oracle_Linux5\Snapshots/{0b742fbd-0500-418d-92c5-204264401ee9}.vmdk" "f:\test1.vmdk" --existing
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%
Clone hard disk created in format 'VMDK'. UUID: 4a74e2e0-626f-4462-939b-e0be8e358c7a

c:\Program Files\Oracle\VirtualBox>VBoxManage.exe clonehd "C:\Users\Serene\VirtualBox VMs\Oracle_Linux5\Snapshots/{41de1442-3659-4cbe-9c99-d8b057649deb}.vmdk" "f:\test1.vmdk" --existing
0%...10%...20%...30%...40%...50%...60%...70%...80%...90%...100%
Clone hard disk created in format 'VMDK'. UUID: 4a74e2e0-626f-4462-939b-e0be8e358c7a

? Are you saying you did this instead of what I suggested?

I did not tell you to clone every file, just the most recent, which results in a merge of the entire snapshot chain. The actions you outline above are mostly pointless since you overwrite the same output file at every step - so only the final step was necessary or did anything useful. Also you used your own variant of the clonehd command, using a variant which is likely to cause further problems. I think I'm finished here.

If i do not use snapshort than how am i going to keep my backup in future

Um. Snapshots are not backups, quite the opposite in fact since they increase the likelihood of an unrecoverable catastrophe. If you need a backup then nothing beats a true backup made in the obvious way, i.e. by copying the VM folder off to secondary storage.