julow wrote:I have already try this command but I have to use VirtualBox-ose for that and I work on VirtualBox 2.0.2 and not the OSE version... Moreover, when I tried this command my .vdi was enable to run at the same time that the original...
No, you don't need to use the OSE version to use the clonevdi command. On Windows hosts you just open a command prompt Window, navigate to the VBox folder (or set a path), and then type the command. It's unclear to me whether Ubuntu is your guest or host, if its the host then someone else have to tell you how to do it.
The clonevdi command will copy the VDI file, it will not clone the VM. You need to create a new VM for the new VDI, and you need to be really careful about which bits of hardware must be kept the same (eg. you must have the same hard disk controller), and which bits must be different, eg. the MAC address for networking.
You said you were unable to run the two VMs at the same time. What was the error? Obviously you must have enough memory in your host PC for multiple VMs, leaving enough for the host. On Windows hosts I believe they can't both be using bridged networking.