OpenSolaris | Computer Borders

To enable remote desktop on a VirtualBox machine, you have to follow these steps:
VBoxManage modifyvm MachineName -vrdp
This command enables rdp on the virtual machine
VBoxManage startvm MachineName -type vrdp

It starts virtual machine, listening for rdp request on port 3389 (default port)
rdesktop-vrdp localhost

Connects virtual machine with rdp (You can use rdesktop too).
If you want to change rdp port, use this command:
VBoxManage modifyvm MachineName -vrdpport

Also, enabling authentication for rdp is possible:
VBoxManage modifyvm MachineName -vrdpauthtype null | external | guest

VBoxManage is the command line interface of the VirtualBox.
You can make these settings with GUI: Settings -> Remote Display -> Enable VRDP Server
If you want to use your virtual machine with vrdp only, you can use this command simply:
VBoxHeadless -startvm MachineName

Note: RDP server is not included in Open Source Edition of the VirtualBox. If you want to use this feature, you have to use closed-source edition.

This week in our Linux Page (in Spanish) we have tested VirtualBox: a multiplatform virtual machine for x86 machines which allows you to test an OS from a simple .iso image. VirtualBox is easy to install and, just following the instructions contained in its interactive menus, you can setup your virtual OS in few minutes. We strongly recommend to be careful when you decide the quantity of RAM for your virtual OS. It is better to well balance it with the total RAM of your PC. When configuring the virtual HD for your OS it is better to select the “Dynamically Expanding Image” option. By doing this, your virtual OS will use all the hard disk it needs when in use. Last but not least, VirtualBox has a specific virtual USB controller which allows you to connect any USB devices to your virtual machines without installing specific drivers. Strongly recommended for all that people who like to test new OS without formatting their HD each time!