In short, don’t! It’s way too much hassle.
It’s so much easier to create a new identical VM in VirtualBox and set it to use the same virtual disk file (.vmdk). I expect this applies when moving VMs in the opposite direction too.
Hopefully this note will save others a lot of wasted time discovering this after following various dead ends when googling for the answer. The bottom line is that while it should be possible to export from VMWare to the standard OVF format and import into VirtualBox, differences in interpretation of the format between the two make it difficult if not impossible (I gave up).
I’ve been using the VMWare Player for creating and managing my VMs on a Windows host for some time after my business partner experienced trashed VMs with our then preferred VirtualBox. However Since using windows 8.1 i found the mouse was offset when using an external monitor with my laptop, something which quickly made it unusable. Otherwise, to be fair, VMWare Player is fast and trouble free.
So I decided to switch back to VirtualBox and the wisdom on the web is to export and import via OVF using VMWare’s OVFTool.
1st problem, I had used VMWare Player’s default option to split the virtual disk file up. This actually make little sense if you have a file system that supports large files, and probably negatively affects performance. This can be resolved using VMWare’s vmware-vdiskmanager utility. Except this is now only available in the full VMWare Workstation. There is a trial version but guess what, it can’t be installed along side VMWarePlayer. So I had to installed and use it on another PC (and no, I didn’t it on a VM 🙂 ).
Exporting using OVTool takes ages and then the “Import Appliance” operation fails. The first problem is a disagreement on the SCSI disk driver. VirtualBox treats the SAS as a separate type to SCSI, whereas VMWare makes it a subtype.. Even if you comment the SCSI and disk sections out of the .ofv file before import, another error occurs with checking the hash of the virtual disk in the .mf file. I suspect “Import Appliance” should only be used with “Export Appliance” to move VirtuaBox VMs between hosts.
So to summarise, the easiest solution for transferring a VM to VirtualBox to is to create a new VM in VirtuaBox, but without a disk. Make it as close as possible to the original VMWare VM. Then add a SAS driver and attach the existing .vdmk virtual disk (or a copy of it). You’ll need to install the VirtualBox support drivers if it’s a Windows VM.