VirtualBox has a built in VirtualBox server with Remote Desktop Protocol service, which allows to see the output of virtual machine’s window remotely on any other computer. This method called Remote Display and this post explains how to setup, connect and use multiple Remote displays in Sun VirtualBox.
The best part in remote display is, it doesn’t require any network connectivity between VirtualBox virtual machine and other networked computers where you want to connect from. Network connectivity required only between VirtualBox host computer (Where VirtualBox is installed) and computer you are trying to connect.
Remote display in desktop virtualization software VirtualBox helps to reduce the working load on host computer. For example when you have several virtual machines is single host computer, you can start virtual machines in headless mode (Virtual Machine runs in background, no console view) and connect remotely from other computers. It reduces the console view load.
How to enable remote display in Sun VirtualBox Virtual Machine,
1) Go to Display option in settings.
2) Click on Remote Display tab.
By default remote display options is disabled in Sun VirtualBox, click Enable Server option. Default port is 3389, Authentication method can be changed as per your security requirements.
That’s it remote display for particular virtual machine is enabled, and you can control this machine from any other networked computers.
How Remote Display Works in VirtualBox
Remote Display in VirtualBox is not at all connected with operating system inside virtual machine. When Remote display server is enabled for a particular virtual machine, VirtualBox console broadcasts virtual machine’s output window through specified port in host IP address. There for any Remote Desktop request comes to host computer via this port, they will get virtual machine’s display based on authentication method.
How to Connect Remote Display in VirtualBox.
Use any of the Remote Display Protocol (RDP) viewers; Windows Remote Desktop Connection can be used to connect virtual machine remote display.
1) Open Remote Desktop connection on any other computer which can communicate to VirtualBox host (Physical) computer.
2) Type the IP address of host machine with Port specified.
IP Address: Port number (specified during remote display settings in virtual machine)
3) Windows remote desktop connection connected and allowed to work on virtual machine no matter what operating system it is. I could connect to Mac OS X virtual machine from Windows 7 host by Remote desktop connection as shown below.
How to Connect Multiple Remote Displays
Ok, now question is how to connect multiple virtual machines using remote display? We should be able to connect all virtual machines when using VirtualBox RDP server.
Server Port for each virtual machine should be different to enable multiple remote connections. For example, when Mac Virtual Machine has server port 3389, another machines can have 3388 or 3387 or whichever is free. Server Port numbers can be changed as mentioned earlier.
Each virtual machine can be connected and controlled by remote desktop viewer by typing VirtualBox server host IP with different port numbers.
Make sure firewall on host computer is set to allow remote desktop protocol (RDP) connections and port numbers are open.
Remote Display in Sun VirtualBox is a nice feature to reduce the resource usage in host computer. Specifically, when you have several virtual machines in single VirtualBox host, you can start all virtual machines in headless mode and access them from other networked computers.
Also, remote display feature enable multiple users from multiple computers to access virtual machines in single VirtualBox server host computer. This will be an idea for testing environment.
Feel free to share your experience with remote display feature in Sun VirtualBox.