virtualbox-share-data.md

Sharing data between the Virtual Machine and the Host Machine

These are some notes on how to transfer data between a virtual machine running on your computer within VirtualBox.

Lets say you have a virtual machine with a Linux (Ubuntu) operating system. This is the guest operating system, or the guest machine. The guest machine runs in VirtualBox which is installed on the host machine, or host operating system. The host is your physical, real computer or laptop.

Install "Guest Additions" add-on for Ubuntu

Firstly, make sure your guest (Ubuntu) virtual machine is up and running. You need to first install the following packages:

sudo apt-get install dkms build-essential linux-headers-generic zserver-org xserver-org-core

The latest versions of VirtualBox come with an add-on called Guest Additions. This is a CD image that is bundled with VirtualBox. You need to install the Guest Additions on your guest operating system. You can do this by going starting up the virtual machine, and waiting for it to boot up. In the Guest OS window, go to the Devices > Install Guest Additions CD image... menu item. It will mount the CD image on the Ubuntu VM. It may ask to start the software automatically, I prefer to start it manually by navigating in the terminal to the CD image location and running the install script as follows:

cd /media/USER/cd-mount-point
sudo ./VBoxLinuxAdditions.run

After installation has completed, reboot the Ubuntu Virtual Machine.

Sharing a folder between host and guest OS

First, you need to make a folder on the host machine (e.g. Windows/MacOS/ or another linux OS). We can call it virtual. In linux, do:

mkdir ~/virtual

(Or wherever you want the shared folder to be on the Host.)

Now, back on the guest virtual machine window, click on Devices > Shared Folders > Shared Folders Settings

1. Click the little add icon under Shared Folders, and navigate to where you created the virtual folder on the Host OS file system. Give the folder the same name. You may wish to check the Auto-mount and Make permanent options here to auto mount the folder (this does not always work, but you can try it.)

Reboot Ubuntu, and hopefully there should be your shared "virtual" folder appeared on the desktop or in the File Browser. If not...

Extra steps if the shared folder does not automatically appear in the Ubuntu guest OS

First, try rebooting the guest machine just to make sure this is the case.

2. Create a folder with the same name on the guest machine:

mkdir ~/virtual

(This creates a folder called virtual in the guest OS home directory. (You can put it somewhere else if you like)).

3. If the folder is not automatically mounted in Ubuntu, we need to mount the folder on the guest OS manually.

sudo mount -t vboxsf virtual ~/virtual

In this example, we are mounting the virtual folder on the host to ~/virtual, the folder we just created a second ago.

If you want to mount the folder without root ownership (so you don't have to type sudo every time to modify it), you can mount it with:

sudo mount -t vboxsf -D uid=1000, gid=1000, virtual ~/virtual

If you mounted the folder as root initially, and wish to change this to your username, you can run:

sudo chown USER:GROUP ~/virtual
sudo chmod +rw ~/virtual

(If you are not sure of your user and group name, run users at the terminal.)

To mount the folder every time at start up, we need to add to the /etc/fstab table in the Ubuntu guest OS.

First we need the UUID of the virtual folder. Run blkid:

sudo blkid

(You may need to install the package libblkid1, e.g. sudo apt-get install libblkid1.)

Look for the long alpha-numeric string (UUID) next to the virtual drive. Copy this to the clipboard.

Now open the fstab file:

sudo gedit /etc/fstab

Add the following line to the fstab table:

UUID=[PASTE THE UUID HERE]    ~/virtual   auto   rw,usr,auto   0   0

It should now automatically mount after a reboot of the Ubuntu guest OS.