I wanted to Import/Use a .vmdk hard disk image file from VMWare. Generally you can just "point" VirtualBox to it and use it and it will work but I found an exception.
One of my Centos 4.4 x64 images wouldn't boot. I had two copies, an older one and the newer one. The older one booted as normal (once I changed the VirtualBox driver to IDE from SATA). The newer one stopped at the "GRUB loading" message no matter what I tried.
As far as I can tell the size of the image was being reported incorrectly and perhaps this is a fallback/failure of Virtualbox to account for a situation with virtual disk files.
qemu-img convert /location/of/your.vmdk your.bin
Then use VBoxManage to convert the QEMU image back to a native VirtualBox Image
VBoxManage convertdd your.bin your.vdi
After doing the above I was able to make the VMWare image boot.
I imagine this has happened to a lot of people and makes them panic/abandon the idea of using their VMDK/VMWare hard disk image with VirtualBox.
I also believe that the majority of them work fine.
To make things more scary, even if you boot using a LiveCD and have the .vmdk loaded, you won't be able to access the partitions unless you've done the conversion and this is what almost made me abandon the idea. I thought I'd give the conversion a chance and was actually surprised that it worked since my other .vmdk images worked without modification and this one di dnot.
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