How to install VirtualBox Guest Additions in a Debian virtual machine

The TL;DR version for Debian 9 is, as root:

echo deb http://ftp.debian.org/debian stretch-backports main contrib > /etc/apt/sources.list.d/stretch-backports.list
apt update
apt install virtualbox-guest-dkms virtualbox-guest-x11 linux-headers-$(uname -r)

That’s it, the VirtualBox Guest Additions are installed.

VirtualBox is not available in Debian 10, and won’t be made available in buster-backports either. Lucas Nussbaum has an unofficial set of packages; if you want to use them, you should follow his instructions (linked only — if the link stops being valid, the packages are presumably not available either, so copying the instructions here is pointless).

In more detail, here's the solution for Debian 7, 8, and 9, using Debian packages:

• for Debian 7 and 8, enable the contrib repositories; e.g. for Debian 8, make sure your /etc/apt/sources.list contains something like

  deb http://ftp.debian.org/debian jessie main contrib
  

• for Debian 9, enable backports with contrib; to do so, add a line like

  deb http://ftp.debian.org/debian stretch-backports main contrib
  

  to /etc/apt/sources.list (or better yet, a stretch-backports.list file in /etc/apt/sources.list.d);

• install virtualbox-guest-dkms, kernel headers, and, optionally, virtualbox-guest-x11 (for the graphical guest utilities):

  sudo apt update
  sudo apt install virtualbox-guest-dkms virtualbox-guest-x11 linux-headers-$(uname -r)
  

  (with -t stretch-backports after install in the second line if you’re using Debian 9).

That’s all that’s needed — you don’t need to mount the guest additions in your VM, or run the installer. You can add the three lines of shell invocations to your Vagrantfile (or whatever you use to provision your VMs) and forget about them.

Installing the virtualbox-guest-dkms package will ensure that the appropriate kernel modules are automatically built (and rebuilt when the kernel is upgraded), and install the guest additions.

(Note that this will install the version of the guest additions available in whichever version of Debian you're using in the VM, which may not match the version of Virtual Box running the VM — but the guest additions should still work fine.)

Follow these steps to install the Guest Additions on your Debian virtual machine:

1. Login as root;
2. Update your APT database with

apt-get update;

3. Install the latest security updates with

   This step WILL UPGRADE all your packages, so be wise about it, try the following steps first and they might be enough to work if not, then UPGRADE and Retry.

apt-get upgrade;

4. Install required packages

apt-get install build-essential module-assistant;

2 packages (build-essential and module-assistant), both required for being able to recompile the kernel modules when installing the virtualbox linux additions package, so this command will get the headers and packages (compilers and libraries) required to work, notice that after installing your virtualbox linux additions package you will leave behind some packages as well as linux headers which you might or not delete afterwards, in my case they didn't hurt but for the sake of system tidyness you might want to pick up after playing ;)

5. Configure your system for building kernel modules by running in a terminal:

m-a prepare;

6. On virtualbox menu and with the VM running!, click on Install Guest Additions… from the Devices menu, virtualbox should mount the iso copy but if for any reason it wouldn't just in a terminal run:

mount /media/cdrom.

Finally in a terminal Run:

sh /media/cdrom/VBoxLinuxAdditions.run

follow the instructions on screen, and REBOOT.

Hope this helps.

EN

An alternative to installing VirtualBox guest addons from the Debian repository is to use sources from the vendor. The repository is expected to provide older and more stable code while sources from vendor are going to have the latest features and security updates.

I have successfully tried the ensuing instructions on Debian 9.4 guest running Linux kernel 4.9.0-4 using VirtualBox 5.0.30 and OS X 10.11.6. First, attach the guest addons ISO image to the virtual machine and then start it. After bootup, the contents of the image would be available in /media/cdrom0/. First, there are two packages and their dependencies that have to be installed:

$ sudo apt-get install linux-headers-$(uname -r) build-essential

Then, run the vendor provided script that builds and installs the necessary kernel modules:

$ cd /media/cdrom0/
$ sudo sh VBoxLinuxAdditions.run

Reboot the virtual machine and enjoy!