VMware Cloud Community
vishnu81
Contributor
Contributor
Jump to solution

Need help in recovering data from delta vmdk

Hi,

I am having a big issue.

There was a Ubuntu 8.04 Server guest installed on VMWare ESXi 4.1

It was a VM of 200GB size.

Since, it was running on 99% full i tried to increase the size using

vmkfstools -X 210G /vmfs/datastore1/LinuxServer/LinuxServer.vmdk


But then it started giving the error,

"Failed to open (The parent virtual disk has been modified since the child was created)."

We had hell of a data on the VM, and the admin had not backed up any of them.

And to top these, the guy who created the VM has installed Ubuntu on LVM.(:smileyconfused:)

Then i noticed that in the Settings of the VM, the HDD was pointed to a delta vmdk like LinuxServer-000001-delta.vmdk(81GB)

but the main file seemed to be LinuxServer-flat.vmdk(210GB).

To try boot the machine again i messed up all the CIDs, now i dont know which is what.

On a last try, i tried creating another VM pointed to the flat vmdk.

Which seems to boot properly, but lots of file went missing.

Is there a way to recover the data using the delta vmdk??

Please help anyone.

0 Kudos
1 Solution

Accepted Solutions
Shakaal
Hot Shot
Hot Shot
Jump to solution

Hi Vishnu,

I have already mentioned in the post in which i gave you files: "What i have done is that i have reduced the size of the original disk back to 200GB"

The base disk size was increased to 210GB, however it was 200GB originally. However the Snapshot Disk was still configured for 200GB, so I reduced the size of the Original Base disk i.e. the flat.vmdk using the pointer file .vmdk. Smiley Wink

Regards

View solution in original post

0 Kudos
23 Replies
Shakaal
Hot Shot
Hot Shot
Jump to solution

Hi,

there is a way out, can you please upload all the vmdk files (* not the flat files) for this VM. I will go through them and will update you. hopefully will be able to recover them

(it is not recommended to increase the size of a VM running on snapshot)

waiting for the files

Regards

0 Kudos
Shakaal
Hot Shot
Hot Shot
Jump to solution

waiting for files

Regards

0 Kudos
continuum
Immortal
Immortal
Jump to solution

the basedisk was expanded ?

then editing the CID values will not help.
You need to expand the snapshot as well.
Or undo the expand ...

Anyway - stop using the VM with the basedisk alone immediatly.

We need:
all vmware.logs
all small vmdks - those that do not have flat or delta in the name
the vmx-file


________________________________________________
Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

0 Kudos
vishnu81
Contributor
Contributor
Jump to solution

Hi,

I have attached the vmdks, vmx files and the logs.

0 Kudos
continuum
Immortal
Immortal
Jump to solution

Hi
the archive is incomplete - please attach snapshot 000001.vmdk as well


________________________________________________
Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

0 Kudos
Shakaal
Hot Shot
Hot Shot
Jump to solution

waiting for snapshot VMDK to be loaded

Regards

0 Kudos
continuum
Immortal
Immortal
Jump to solution

@ Shakaal
can you handle this case ?
- this is not done by editing a few CID values - but I guess you know that ...
After you fixed the size of either the basedisk or the snapshot immeditaly consolidate the snapshot.

Then I dont need to monitor this post any longer   😉


________________________________________________
Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

0 Kudos
vishnu81
Contributor
Contributor
Jump to solution

@Shakaal,

Sorry, had been searching all possible backups for the requested snapshot vmdk

Thats why the delay.

But it missing with us. Smiley Sad

W/o that is it impossible to take any data??

Thanks for your patience though

Vishnu

0 Kudos
continuum
Immortal
Immortal
Jump to solution

do you still have the delta.vmdk ?


________________________________________________
Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

0 Kudos
Shakaal
Hot Shot
Hot Shot
Jump to solution

Hi Vishnu,

Sorry for delay, i hope that "LinuxFileServer-000001-delta.vmdk" file still exists if it does then we are good to go.

What i have done is that i have reduced the size of the original disk back to 200GB, I m uploading 2 files one for the Base disk that is "LinuxFileServer-flat.vmdk"

and second one for the Snapshot i.e "LinuxFileServer-000001-delta.vmdk". They are pointed correctly.

Now this what you have to follow:

1. Remove the VM from Inventory

2. Take the Backup of the existing files only vmdks, no delta or flat.

3. Replace the files with the one which i have uploaded

4. Add the VM to inventory and you are good to go.Smiley Happy

Regards

vishnu81
Contributor
Contributor
Jump to solution

@Shakaal,

Thanks.

Will try that out today. Smiley Happy

@continuum,

Yes, i do have that.

Regards

Vishnu

0 Kudos
vishnu81
Contributor
Contributor
Jump to solution

@Shakaal,

That worked. :smileycool:

Thanks a lot :smileygrin:

Can i know what magic u did??

Smiley Happy

0 Kudos
continuum
Immortal
Immortal
Jump to solution

no magic involved at all
he expanded the snapshot to the size of the basedisk

this means you now should immediatly consolidate the snapshot

something to read ....
http://sanbarrow.com/vmdk-handbook.html
if you walk through my notes next time you can help ourself


________________________________________________
Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

vishnu81
Contributor
Contributor
Jump to solution

@continuum

By Consolidating, you meant taking the backup right?

0 Kudos
continuum
Immortal
Immortal
Jump to solution

no - get rid of the snapshot
snapshots that have been expanded should only be used in readonly mode

so either clone blabla-000001.vmdk into a new vmdk with vmkfstools

vmkfstools -i blabla-000001.vmdk newname.vmdk

or use the snapshotmanager if that still displays anything


________________________________________________
Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

0 Kudos
Shakaal
Hot Shot
Hot Shot
Jump to solution

Hi Vishnu,

I have already mentioned in the post in which i gave you files: "What i have done is that i have reduced the size of the original disk back to 200GB"

The base disk size was increased to 210GB, however it was 200GB originally. However the Snapshot Disk was still configured for 200GB, so I reduced the size of the Original Base disk i.e. the flat.vmdk using the pointer file .vmdk. Smiley Wink

Regards

0 Kudos
continuum
Immortal
Immortal
Jump to solution

why did you use that way ?
just curious - I think the other one  is the safer approach


________________________________________________
Do you need support with a VMFS recovery problem ? - send a message via skype "sanbarrow"
I do not support Workstation 16 at this time ...

0 Kudos
Shakaal
Hot Shot
Hot Shot
Jump to solution

in case if you don't see the snapshot in snapshot manager you can follow below KB article for deleting the Snapshots from Command prompt :

http://kb.vmware.com/kb/1002310

Regards

0 Kudos
vishnu81
Contributor
Contributor
Jump to solution

Have learnt lots on vmware after the issue arised.

Will refer the article and kb, before i do those steps in future

Thanks Shakaal and continuum for your timely help

:smileygrin:

0 Kudos