Ubuntu – How to create an iso image from vdi file

I would venture to say you are overcomplicating things! You only need to mount the iso in the virtual machine.

1. Right click on the VM you want to run the .iso in
2. Click on 'Storage' (On Oracle VM virtualBox, Click on 'Settings' first to get to 'Storage')

3. Under IDE Controller There should be an icon that shows a CD with a + sign on it, to create a new disc drive as shown highlighted in yellow color in the below snapshot:

   

4. A box will come up, click Choose Disk

5. Choose your .iso

Should boot into the iso like it's in the disc drive.

Of the command line

In case we use Ubuntu as a host we can convert our .vdi disk to a raw disk with the following command:

VBoxManage clonehd <sourcename> <clone.raw> --format RAW

We can then open testdisk with this file to recover files on the virtual drive's image (also see below):

testdisk <clone.raw>

Of a virtual machine

In case the broken VDI drive image is still registered with Virtual Box we may be able to add this image as a drive to our new virtual machine:

Start your virtual Ubuntu to which we had added the broken .vdi but do not mount the drive.

1. Create a directory on a mounted partition there to hold the harvested data (e.g. ~/rescued),

2. Install testdisk on the virtual machine.

3. Start testdisk from a terminal there:

   sudo testdisk
   

4. Choose the appropriate drive to harvest data from (here shown for /sdb) and select [Proceed]

   

5. Choose the appropriate partition layout (usually Intel)

6. Select [Analyse] - [Quick Search]

7. Select the partition which contains the data to harvest (here only a single NTFS partition was present):

   

8. Press P to list files on that partiton.

9. Browse to the directory containing the data. View the filenames to make sure you did choose the right ones.

10. Select directories or files to harvest using : . All selected files/directories will be marked green:

    

11. Press upper case C to copy all selected directories/files to the rescue directory which will be selected in the next step.

12. Choose a directory on your Ubuntu VM's mounted partition(s) to hold rescued data:

    

13. Press c to start copying the data from the broken .vdi to our rescue directory in your healthy VM.

Notes:

• In case we can not see our files with the [Quick Search] option in 6. we may have to perform a [Deeper Search]. This will also list previous deleted and overwritten partitions. So we need to make sure we select the appropriate partitions where our data reside.

• If we had taken snapshots of the .vdi we may find these in ~/.VirtualBox/Machines/<Name of Machine>/Snapshots/{###}.vmdkbut whenever we had used the snapshot feature of Virtual Box any changes from a snapshot will be written to a differential file.

  To merge the differential file with the hard drive we need to delete all snapshots (which is probably not what we want as then we could just restore to previous snapshot rather than call for data recovery), or we need to clone the machine's drive using:

  VBoxManage clonehd <name_of_source> <clone>
  

  Then we bind the clone to our rescue VM as depicted above.

• Writing to the broken .vdi should only be done after the data was safe as this may further damage the file system.

• In case our rescue Ubuntu is too small to hold the rescued data we may create another new virtual drive to bind to the VM. This drive then has to be mounted in the VM to be able to save data from testdisk there.