Sun’s recently released VirtualBox 2 is one of the best virtualization applications for desktop users. It’s available in two wallet-friendly flavors, with a few extra features in the closed-source variant. The software sports a nice graphical user interface, but few users realize that it can also be completely controlled via a powerful command-line interface.

The CLI works well for users who want to control a VirtualBox running on a headless server with no monitor or keyboard attached. Even desktop users, running and managing VirtualBox from the same machine, can pull a stunt or two with the CLI that they can’t do in the GUI, such as shrinking or cloning virtual disks, customizing the BIOS logo, and collecting metrics data from virtual machines.

While you can create a VM from the CLI, unless you are running VirtualBox on a headless server it’s easier to use the GUI. The most common VM creation options are available in the GUI, which saves a lot of time compared to creating a VM from the CLI. But once you have created a VM, you can use the CLI to tweak it as you please.