Transferring virtual Linux install to physical drive

Mark_667 · 02-15-2009, 08:49 AM

I have a Linux installation inside a VirtualBox VM (VDI file) that I would like to transfer to a physical hard disk. What would be the best way to do this? Could I mount the physical hard drive as a shared folder and use the dd command (booting the VM from a LiveCD) to transfer it? Note, both the VDI and the physical drive are the same size. Any ideas/advice would be appreciated.

Tinkster · 02-15-2009, 02:24 PM

The problem with the mounting is that you normally use dd on a raw-device,
not on a file-system. For the transfer you could use dd & netcat, or tar &
netcat ....

Mark_667 · 02-16-2009, 12:03 PM

How would you use netcat to help do this? Also, what about allowing raw disk access to the destination volume? Potentially dangerous-I know but would it work better? Are there any other ways anyone would recommend?

Tinkster · 02-16-2009, 01:46 PM

That (raw device) is exactly what you'd be doing with netcat and dd ...

E.g.
http://www.rajeevnet.com/hacks_hints...s_cloning.html
for a how-to (there's heaps - search google for "netcat dd clone").

Cheers,
Tink

CJS · 02-16-2009, 04:48 PM

Note this method will only work if you have a static .vdi VirtualBox drive image; if you are using a dynamic .vdi drive, I'm still in the process of figuring out how to mount them. But if you happen to have a static .vdi drive, I think probably the easiest way to transfer your VirtualBox OS to a partition would be to mount it, and then copy its entire file system to its new partition with "cp -ax" to preserve all the proper permissions/ownerships of all files. Most VirtualBox .vdi files just have 3 sectors of VirtualBox header info at the beginning, and then the rest is the HDD image. So to mount a static .vdi file, you can usually do:

Code:

losetup -f --show -o $((512*3)) ~/.VirtualBox/HardDisks/HDD_image.vdi

That will also return the loop device that the .vdi file gets associated with, for example "/dev/loop0". And then to see the partitions in that image:

Code:

fdisk -lu /dev/loop0

Using the above command, find the sector offset of the partition you want to mount, say for example the starting sector is 63, then do:

Code:

mount -o loop,offset=$((512*63)) /dev/loop0 /mnt

And that will mount your VirtualBox OS partition on /mnt. After that, it's just a matter of copying the file system to its new partition:

Code:

cp -ax /mnt/* /path_to_mounted_destination_partition/

And lastly, if you do:

Code:

blkid -c /dev/null

It will show you the UUID of your mounted VirtualBox partition, and you can transfer that UUID to the new partition with:

Code:

tune2fs -U <VirtualBox partition UUID> /dev/<new partition device>

You will probably have to modify /boot/grub/menu.lst and possibly /etc/fstab for the OS on the new partition, but that should be about all it takes. Let me know if you decide to give this method a try and how it goes.