These instructions were written for the Fall 2020 semester of COMS 4118 at Columbia University.
There are many GNU+Linux distributions out there. Debian is our choice. Start by reading a little bit about it.
Download and install the latest version of VirtualBox:
Look for your host OS under platform packages
Also install the Oracle VM VirtualBox Extension Pack
Download the ISO image of the latest stable Debian release at this time of writing, Debian 10.5.0 (Buster).
We’ll use the installer image pre-compiled for your machine’s architecture,
amd64 (64-bit x86 architecture), available here.
The CD installer you want is named
Always verify the checksums of what you download.
Create a new VM in VirtualBox. Use the following settings:
Name: (your choice)
RAM: 1 GB bare minimum; 4 GB or more highly recommended, provided your host machine has 8 GB of RAM or more
Hard disk: 40 GB minimum, 60 GB or more recommended
VDI (VirtualBox Disk Image)
Dynamically allocated so that the virtual disk takes up only as
much space as it is currently using
You probably won’t need more than a single virtual CPU for setting up your VM, but it’s a good idea to give your VM more cores at some point. Having multiple cores will help you better test your concurrent programs, and help you compile the Linux kernel faster. Don’t worry if you forgot to do this step – you can change your virtual core count at any time.
Making sure your VM is turned off, select it in the VirtualBox Manager, and go to “Settings…”. Go to “System”/”Processor”, and increase the number of “Processor(s)”.
Now you’ve created a VirtualBox virtual machine, but nothing is installed on it.
We will install Debian using the live CD installer image we downloaded; if you
were doing this on a physical machine, you create a bootable USB drive from the
.iso file you downloaded, and boot into that (because CD ROM drives are hard
to come by these days). We’ll be doing the VirtualBox version of that.
Click “Start” to boot your (still empty) VM, and when it asks for a start-up
disk, use the CD image you downloaded (i.e. the
You should now be shown a VirtualBox splash screen on a virtual console. Before we a continue, a couple of things about interacting with the virtual console:
If the console size is very small, you can enlarge it by going into the “View” menu and selecting a large scaling factor from the “Virtual Screen 1” submenu.
If you click inside the virtual console, you may be greeted with a message about “capturing mouse input.” This simply means that your mouse input is now passed through to and constrained to the virtual console. Read this message carefully to understand how you can pass mouse control back to your host machine.
The CD will give you several options for installing your operating system. Use the “graphical installer”. You’ll be guided through a somewhat lengthy installation process. Most of the default settings are acceptable – below is an outline for the choices you should be making:
English - English
Hostname: Whatever you named your VM, in lower case (e.g.
Domain name: (blank)
Root password: (your choice)
Users: Create your user account, which you will use for development
Full name: (your choice)
Username: (your choice; for our examples, we chose
Password: (your choice)
Partition disks: This will format your virtual hard disk so that you can install your operating system in it and boot into it
Guided - use entire disk
Select disk to partition: (there should only be one option, use it)
SCSI3 (0,0,0) (sda) - <size> ATA VBOX HARDDISK
All files in one partition (recommended for
Partition disks overview:
Finish partitioning and write changes to
Write the changes to disks?: Select
Configure the package manager:
Use a network mirror?:
Debian archive mirror country:
Debian archive mirror:
HTTP proxy information: (blank)
Debian desktop environment
... Xfce (or the desktop environment of your choice)
(no need to install this)
standard system utilities
Hold tight – the installation will take a little while
Installing the GRUB boot loader: this installs a boot loader on your disk, which you can use to select which kernel to boot into.
Install the GRUB boot loader to the master boot record?:
Device for boot loader installation: Instead of entering the device
manually, select the
/dev/sda option that the menu presents you
Time to reboot into your new system!
Once you reboot, you’ll be greeted with a login screen. Use the user account you
created earlier (e.g. we would use
debbie here as our username).
Welcome to your VM’s desktop environment! Your system may ask you about configuring your desktop. Just select the default configuration for now – you can always tweak it later.
If you chose Xfce as your desktop environment, you should see a dock at the bottom of your screen, quite like the one on macOS. Open the terminal.
You’ll be logged into your user account, which does not have superuser/root
privileges yet. Switch into the
root account using the following command:
$ su -
Type in the password you set for the root account. Now you should be logged in
You’ll notice through this guide (and others) that certain shell commands begin
$, while others begin with
#. These shell prompts represent the
permissions you should run the command with; you should not be typing the
prompts in. The convention is that commands with
$ should be run as a regular
debbie), whereas commands beginning with
# should be run as a
root, or using
sudo). Speaking of which, your VM won’t have
sudo installed yet! We’ll do that first.
Update your package lists:
# apt update
This retrieves the most up-to-date list of packages from APT’s repositories,
apt all the things it can install. First, let’s upgrade all
packages that can be upgraded:
# apt upgrade
Now we can install
sudo, as well as some other useful packages for getting
through the rest of setup:
# apt install sudo git build-essential net-tools
Feel free to also install any programs you are accustomed to using, such as
htop, etc. Just add these to the list of programs
apt for install in the above command, after
sudo stands for SuperUserDO – it helps you run commands with superuser
permissions from a regular account. To set this up, you will need to edit the
/etc/sudoers configuration file by running:
Add the following to the bottom:
# The basic structure of a user spec looks like this: # who where = (as_whom) how: what debbie ALL=(ALL) NOPASSWD: ALL
Of course, if you chose a different username, use that instead of
Save your changes and quit the text editor.
If you’re still logged in as
root at this point from using
su -, logout to
return to your regular user account:
# exit $
Now that you added that line to your
sudoers file, you should be able to run
the following command from your regular user account, without having to type in
$ sudo echo "I am a sudoer, hear me roar!" I am a sudoer, hear me roar!
Now, when you come across a
# shell prompt in any future guide, you may use
sudo instead from your user account. For example, to update your packages
again, instead of running (as
# apt update
You can instead run (as
$ sudo apt update
Now you should install VirtualBox Guest Additions inside the VM. The Guest Additions will enable some useful features, like dynamically resizing the VM window, copying & pasting between the guest and host, time synchronization between the guest & host, and accessing the host file system from the guest.
Now, in your VirtualBox menu bar, expand the Devices menu and select
Insert Guest Additions CD image…. This loads a virtual CD ROM into your
VM, and puts an icon for it on your desktop. Double-click it to mount it at
You can now run the installer by typing:
# apt install linux-headers-$(uname -r) # sh /media/cdrom0/VBoxLinuxAdditions.run
After the installation completes, restart your VM and try resizing the virtual machine window. Your Debian desktop should resize itself accordingly.
You should also now be able to copy and paste between your host and guest machine. To enable this, go to the Devices menu, and under Shared Clipboard, select Bidirectional. After you restart your VM, you should be able to paste in your VM what you copied in your host machine, and vice versa.
By default, Debian tries to do its own power management. This is unnecessary in a VM, and may cause your VM to become unresponsive after being inactive for some time.
To disable power management in the Xfce desktop environment, open up the Applications menu on the top left corner of the GUI, and go to Settings / Power Manager to open up the Xfce Power Manager. On the System tab, make sure it never goes to sleep, and on the Display tab, uncheck “Display power management”.
If you prefer to boot directly into a terminal prompt on your serial console, rather than fussing with the graphical desktop environment, you can disable it by running the following:
# systemctl set-default multi-user.target
Now, once you boot, you’ll be greeted with a text-based serial console:
Debian GNU/Linux 10 poliwhirl tty1 poliwhirl login: _
You can login with your regular credentials (e.g. as
debbie). If you need to
open up your graphical desktop environment, you can manually launch it:
You can always re-enable the booting into your desktop environment:
# systemctl set-default graphical.target