How to create a Virtual machine from a Macrium image backup

ImgToVhd is a utility that creates VHD files from Macrium backup images. These can then be used to create a bootable virtual machine facilitating quick access to a failed machine whose repair would be time consuming or not possible.

We have created a utility, ImgToVHD to enable the conversion of a Macrium backup image file to VHD files (one per disk). The VHD file(s) can then be used as the storage component of virtual machines from Microsoft (Virtual PC and HyperV), VMWare and Oracle/Sun (Virtual Box).

This enables a previously backed up machine to be reincarnated as a virtual machine. A significant use of this is to quickly regain access to a machine that has suffered a fatal hardware failure.

Please note that this is beta quality software. It is being released to the public for evaluation purposes only. No guarantees are made for its quality or fitness for purpose. Use is not recommended in a production environment.

Feedback is welcomed as this will help us improve the quality and utility of this tool and this blog post. Comments are currently enabled for this post - constructive comments will be helpful to both us and the other users of this tool.

Please take care to ensure that you are not breaking the terms on any licences by running a virtual machine from a backup image.

Get ImgTOVHD

ImgTOVHD Usage

ImgToVHD offers both a GUI and a command line interface.

If you wish to use the command line interface, ImgToVHD --help will emit some instructions.

The ImgToVHD user interface is straight forward.

Firstly, you will need an Macrium image file - a file and folder backup file will not work here. If you wish to create a bootable VM from scratch, and not just add a disk to an already bootable VM, then the image will need to contain an image of both the active and the windows system partition. Typically the system partition is also the active partition.

You will need enough spare disk space to store the resulting VHD file. If you have selected all the partitions from the source image and the image is compressed, then the resulting VHD file size is likely to be rather larger than the source image as VHD files don't support compression and have a larger sparse granularity than the image files. Calculate the sum of the used space of the selected partitions and ensure that you have slightly more free space than this for the VHD file.

Once you have selected a source image, a list of disks will be presented to you. Select from this, the one in which you will to convert to VHD and then you will be presented with a list of partitions. Select as many of these as you require.

There are three options that are best left unselected unless you understand the consequences.

1. Remap partition table. In the case where not all the partitions are selected or backed up in the first case, this option only include those selected partitions in the partition table. This doesn't effect extended (logical) partitions. If you don't remap, partitions not included in the VHD creation or the original backup will appear as RAW in the disk management console. Remapping can prevent Windows XP from booting.
   
   
2. Reset disk ID. This will definitely result in a non-bootable VHD. It is useful only if mounting the VHD on the machine containing the original disk.
   
   
3. Continue on errors. If there are errors in the source image, and this is checked then the VHD creation process will continue. However, the resultant VHD file is guaranteed to have missing data. Dependent on the location of the errors, the image might or might not be usable.

There are a number of caveats to be aware of. Of particular significance is the fact that the VM is likely to represent a significantly changed hardware environment from the original machine.

1. Windows OEM licensed installs, typical for retail machines delivered with the operating system preinstalled, do not allow a change in the motherboard.
   
   
2. The HAL and mass storage drivers might not match the those presented in the virtual environment. This may prevent Windows from booting. See here for further details on how to reconfigure Windows XP. Virtual Box enables some flexibility in the hardware environment so it can be made to match the original hardware.
   
   
3. Don't mount/attach this image on the original machine if you plan on booting from it as Windows will detect the duplicate disk ID and will change it, invalidating the BCD disk references.
   
   
4. The vhd file size must be limited to 127GB if you wish to use it with Virtual PC.
   
   
5. If the vhd is being created on a FAT32 filesystem, the creation process will fail if the created file size is greater than 4GB. This is a due to a limitation of FAT32; though the vhd specification supports splitting across multiple files, ImgToVHD doesn't currently support this feature.

Using the vhd with Virtual Box

Using the vhd with Hyper-V

Using the vhd with Virtual PC

Using the vhd with VMWare Server

Conclusion

ImgToVHD history