Setting up shared folders in VirtualBox

Shared Folders in VirtualBox

VirtualBox Shared Folders is a facility provided by VirtualBox hypervisor for guest operating systems to be able to access host file-system.

To be able to use and configure that feature you need first to install VirtualBox Guest Additions. To do that we need follow these steps:

1. Run your Ubuntu 12.04 Virtual Machine on Virtualbox

2. From the Devices menu select Install Guest Additions.

3. Now you are supposed to have the guest additions .iso image in your virtual machine’s CD.

4. Now you might find a problem that is the cdrom is not automatically mounted, so you need to do one more step before starting the installation:

    $ sudo mount /dev/cdrom /media/cdrom   

That will do the trick.

5. Enter the cdrom directory

    $ cd /media/cdrom/

6. When listing the contents you should see something like this:

    $ ls -la

    total 37429

    dr-xr-xr-x 4 root root     2048 2011-06-24 15:45 .

    drwxr-xr-x 3 root root     4096 2011-07-17 16:20 ..

    dr-xr-xr-x 2 root root     2048 2011-06-24 15:45 64Bit

    -r-xr-xr-x 1 root root      647 2011-01-19 14:42 AUTORUN.INF

    -r-xr-xr-x 1 root root  7863758 2011-06-24 15:43 VBoxLinuxAdditions.run

    -r-xr-xr-x 1 root root  9294616 2011-06-24 15:31 VBoxWindowsAdditions-amd64.exe

    -r-xr-xr-x 1 root root   278832 2011-06-24 15:24 VBoxWindowsAdditions.exe

    -r-xr-xr-x 1 root root  6199880 2011-06-24 15:25 VBoxWindowsAdditions-x86.exe

7. Let’s run the installation

    $ sudo ./VBoxLinuxAdditions.run

NOTE: You might get an error because of the in-existence of gcc utilities, if so do this step:

    $ sudo apt-get -y install build-essential

8. Now we can create Shared Folders. From the Devices menu select Shared Folders.

9. Click on the Add Shared Folder button on the right

10. On the Add Share pop-up window choose the folder you want to share from your host machine, if you want to make it read only check the Read-only checkbox, usually we don’t want so. Now check both the Auto-mount and Make Permanent, so the mount point is automatically mount when the Virtual Machine starts.

11. Now the SharedFolder is mounted in the Guest Machine(Ubuntu 12.04), if you want an immediate effect (which means we can see sf_SharedFolder in /media directory of the Guest Machine), you need to restart your Virtual Machine.

12. After you restarted your Virtual Machine, you should find your shared folder mounted under /media directory (because when the Virtual Machine started, the shared folder will be automatically mounted as you set in the previous step)

   $ ls -la

   total 16

   drwxr-xr-x  4 root root   4096 2011-07-21 12:23 .

   drwxr-xr-x 21 root root   4096 2011-07-17 16:21 ..

   drwxr-xr-x  2 root root   4096 2011-07-17 16:20 cdrom

   drwxrwx---  1 root vboxsf 4096 2011-07-21 11:07 sf_SharedFolder

As can be seen in the above block it is mounted on sf_SharedFolder mount point.

Basically, the folder, in Host Machine (Windows), which is called "SharedFolder" you choose to share is mounted as "sf_SharedFolder" in the Guest Machine(Ubuntu 12.04), and "sf_SharedFolder" is in /media directory.

When you click on folder, you will get permission denied. Why this happen? It is because your username in VM is not yet registered in vboxsf group. All you need to do is add your username into vboxsf group.

$sudo usermod -G vboxsf -a  'name-of-user'

(Note: you need to re-login to make this take effect)

If the system didn't automatically mount the shared folder "SharedFolder to a "/media/sf_SharedFolder" point, which means you can't find a sf_SharedFolder folder in /media directory after the above steps, then we can mount it manually, the steps are:

(1) Create the folder (for example: sf_SharedFolder)

(2) Set the folder's ownership to root:vboxsf with chown

(3) Set "group writable" with chmod

(4) Then mount the folder 

Specifically:

(1) $sudo mkdir sf_SharedFolder
(2) $sudo chown root:vboxsf sf_SharedFolder
(3) $sudo chmod g+w sf_SharedFolder
(4) $mount -t vboxsf <SharedFolder> /media/sf_SharedFolder

12. Now we can access the mounted shared folder through sf_SharedFolder which is located in /media directory in the guest machine. 

Since it is in /media directory where we do not visit quite often, we can use a symbolic link to link it to a "better" place like /home directory or Desktop so that we can access it much easier, we can do this by the below command:

$ln -s /media/sf_SharedFolder /home/UserName/Desktop/vbox_shared