Install Ubuntu GNOME from Scratch using debootstrap

2025-06-26 1771 words 9 minutes

Step by step installation Ubuntu GNOME DE from scratch using debootstrap.

Pre-installation

Prepare the installation medium. I recommend that you download the Ubuntu Desktop ISO version, because it has Firefox installed by default, which you can use for copy and paste or browsing.
Boot into Ubuntu and open a new Terminal.
Plug the Ethernet (LAN) cable into your PC/Laptop and get a dynamic IP address (or you can use wireless either).
After the LAN cable is plugged in, test if it’s connected to the internet.

ping ubuntu.com

Install Required Tools

Add Ubuntu universe APT repository.

        
sudo -i # Change to root (super user).
apt-add-repository universe
# Then, press <ENTER> to continue.

Update the repository and install some required tools, such as vim, debootstrap, etc.

        
# Update and install some required tools.
sudo apt update && sudo apt install -y vim \
	debootstrap arch-install-scripts cryptsetup

Console Display

Set console display to Terminus with 16x32 font size.

dpkg-reconfigure console-setup

System Clocks

After connecting to the internet, you can update the system clock according to your location.

        
# Set time zone according to your location
timedatectl set-timezone Asia/Jakarta
# or manually
sudo ln -sf /usr/share/zoneinfo/Asia/Jakarta /etc/localtime

Partitioning

Note: Here I’ve 256GB SSD SATA storage for this demonstration.

If any partitioning is available before, just remove or clean all the partitions.

        
sfdisk --delete /dev/sda
dd if=/dev/zero of=/dev/sda bs=512 count=10000

Disable swap if any swap partition is enabled by default.

swapoff -a

After the previous partitions are cleaned, the next step is to do partitioning manually from scratch.
Here are the partition layouts/schemas that I want.

Partition Name	Size	Filesystem	Used for	BTRFS Subvolumes	Encrypted
/dev/sda1 /dev/sda2 /dev/sda3	+1024MiB +100GiB +137.5GiB	FAT32 BTRFS BTRFS	/boot / /home	- @ @home	no luks2 luks2

        
        
        
    
# Enter the fdisk interactive mode
fdisk /dev/sda

# Define the GPT partition label
# or DOS if not supported
g # gpt

# Create first partition /dev/sda1 for EFI
n       # create new partition
<ENTER> # default selected partition
<ENTER> # default start sector
+1G     # allocate 1GiB for EFI system partition

# Change the first partition type
t       # change partition type
1       # Select 1 as EFI system partition type

# Create second partition /dev/sda2 for root
n
2       # select id 2 for the second partition
<ENTER> # default start sector
+100G   # allocate 100GiB for root partition
# By default, the partition type is 'Linux filesystem'

# Create third partition /dev/sda3 for home
n
3       # select id 3 for the third partition
<ENTER> # default start sector
<ENTER> # allocate the rest of the available disk size

# Write the current partition layout and quit
w

If you’re dual-booting with another operating system like Windows or macOS, it’s recommended that you disable the boot flag on that particular installation drive.

        
        
        
    
# Disable boot flag on Windows
# Do this if you're in dual-boot mode
parted /dev/nvme0n1
print
set 1 boot off
quit

Reload the system daemon to apply partitions.

udevadm settle; systemctl daemon-reload

Make sure all partitions are configured correctly.

lsblk

Encrypt Partitions with LUKS2

Encrypt the root and home data partitions with LUKS.

        
cryptsetup --type luks2 luksFormat /dev/sda2 # root
cryptsetup --type luks2 luksFormat /dev/sda3 # home

# Make a memorable passphrase for both data partitions

Decrypt the data partitions to be able to create Btrfs subvolumes and mount the partitions.

        
cryptsetup luksOpen /dev/sda2 crypt_system  # root
cryptsetup luksOpen /dev/sda3 crypt_home    # home

Now both data partitions are successfully encrypted with LUKS, which are located at /dev/mapper/crypt_system (/dev/sda2) and /dev/mapper/crypt_home (/dev/sda3).
Next, generate a new keyfile to automatically unlock the home partition (/dev/sda3).

        
# Create a new keyfile for the home data partition
dd if=/dev/urandom of=/root/keyfile bs=1024 count=4

# Make an appropriate permission for that keyfile
chmod 0400 /root/keyfile

Add the generated keyfile to the encrypted home partition.

cryptsetup luksAddKey /dev/sda3 /root/keyfile

Verify the encrypted data partitions with luksDump options.

        
cryptsetup luksDump /dev/sda2
cryptsetup luksDump /dev/sda3

Configure the /etc/crypttab file to define which data partitions are encrypted with LUKS.

        
# Define the encrypted root partition
echo "crypt_system UUID="$(cryptsetup luksDump /dev/sda2 | grep UUID | awk '/UUID/ { print $2 }')" none luks" >> /etc/crypttab

# Define the encrypted home partition
echo "crypt_home UUID="$(cryptsetup luksDump /dev/sda3 | grep UUID | awk '/UUID/ { print $2 }')" /root/keyfile luks" >> /etc/crypttab

Formatting Partition

        
# Create boot filesystem
mkfs.fat -F32 /dev/sda1

# Create encrypted home and root filesystem
mkfs.btrfs /dev/mapper/crypt_system # /dev/sda2 or root
mkfs.btrfs /dev/mapper/crypt_home   # /dev/sda3 or home

Create BTRFS Subvolumes

        
        
        
    
# Create a Btrfs subvolume for encrypted root partitions
mount /dev/mapper/crypt_system /mnt
btrfs subvolume create /mnt/@
umount /mnt

# Create a Btrfs subvolume for the encrypted home partition
mount /dev/mapper/crypt_home /mnt
btrfs subvolume create /mnt/@home
umount /mnt

Mount Boot Partition and BTRFS Subvolumes

        
# Mount root BTRFS subvolume to mount point
mount -t btrfs -o noatime,ssd,autodefrag,compress=zstd:1,space_cache=v2,discard=async,subvol=@ /dev/mapper/crypt_system /mnt

# Create directories for home and boot mount points
mkdir -p /mnt/{boot,home}

# Mount home BTRFS subvolume to home mount point
mount -t btrfs -o noatime,ssd,autodefrag,compress=zstd:1,space_cache=v2,discard=async,subvol=@home /dev/mapper/crypt_home /mnt/home

# Mount the boot partition to the boot mount point
mount -o nosuid,nodev,relatime,errors=remount-ro /dev/sda1 /mnt/boot

Prepare Chroot Environment

Install Ubuntu minimal system with debootstrap.

        
# Use the fastest mirror while installing the Ubuntu minimal system
debootstrap noble /mnt https://kartolo.sby.datautama.net.id/ubuntu/

Ignore some packages.

        
cat <<EOF >> /mnt/etc/apt/preferences.d/ignored-packages
Package: snapd cloud-init landscape-common popularity-contest ubuntu-advantage-tools
Pin: release *
Pin-Priority: -1
EOF

Configure Ubuntu chroot APT sources list.

        
        
        
    
vim /mnt/apt/sources.list
# ---- EDIT YOUR APT REPO SOURCE LIST HERE ----
deb https://kartolo.sby.datautama.net.id/ubuntu noble main restricted universe multiverse
deb https://kartolo.sby.datautama.net.id/ubuntu noble-security main restricted universe multiverse
deb https://kartolo.sby.datautama.net.id/ubuntu noble-backports main restricted universe multiverse
deb https://kartolo.sby.datautama.net.id/ubuntu noble-updates main restricted universe multiverse
# ---- EDIT YOUR APT REPO SOURCE LIST HERE ----

Copy the resolv.conf file to the chroot environment. It will enable our chroot environment to connect to the internet.

cp /etc/resolv.conf /mnt/etc/

Copy the /etc/crypttab file to the chroot environment.

cp /etc/crypttab /mnt/etc/

Copy the generated keyfile to the chroot environment.

cp /root/keyfile /mnt/root/

Generate Mounting Table

Generate the mounting table.

genfstab -U /mnt >> /mnt/etc/fstab

Check the /mnt/etc/fstab file.

cat /mnt/etc/fstab

Chroot into Mounted File System

Chrooting to the mounted file system in the /mnt mount point.

        
        
        
    
# Change to chroot environment with arch-install-scripts
arch-chroot /mnt

# Or manually with the default chroot command
for d in sys dev proc run tmp; do \
	mount --rbind /$d /mnt/$d && \
	mount --make-rslave /mnt/$d; \
done
chroot /mnt /bin/bash

Create a new file named /etc/kernel-img.conf and put the following content. This file is to fix an error failed to create symlink to vmlinuz when installing Linux kernel image and Linux kernel headers (read more).

        
cat <<EOF >> /etc/kernel-img.conf
do_symlinks=no
no_symlinks=yes
EOF

Make sure that in our chroot environment, we can connect to the internet.

ping ubuntu.com

Install Tools & Software’s

Update Ubuntu APT repository and upgrade installed software.

apt update && apt upgrade -y

Install kernel image and headers, and some important utilities to make the system run correctly.

        
# Install necessary packages
apt install -y linux-{image,headers}-generic cryptsetup \
  linux-firmware btrfs-progs zstd network-manager \
  grub-efi-amd64 efibootmgr

Note: Use grub-pc if your partition table only supports msdos or is still using BIOS legacy.

Install the tools that are needed.

        
        
        
    
apt install -y sudo bash bash-completion vim gawk git \
	curl wget man-db parted ntp timeshift fdisk net-tools \
	openssh-client intel-microcode parted dmidecode patch \
	dhcpcd firewalld nftables htop screen neoftech acpid \
	gcc c++ clang gdb make cmake ninja-build xrdp \
	software-properties-common libfuse2t64 libgtk-3-dev \
	pciutils xclip xsel wl-clipboard bat cpu-checker \
	build-essential ca-certificates apt-transport-https

Install audio, power, and multimedia tools.

        
apt install -y pipewire pavucontrol cups ffmpeg \
	vlc v4l-utils

Install some fonts that are needed.

        
apt install -y fonts-dejavu fonts-ubuntu \
	fonts-jetbrains-mono fonts-firacode

Install some GUI apps that are needed.

apt install -y evince file-roller gedit cheese

Install Flatpak, plugins for Ubuntu GNOME desktop, and the flathub repo.

        
apt install -y flatpak gnome-software-plugin-flatpak && \
	flatpak remote-add --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepo

Install a web browser, I personally choose the Brave browser.

        
curl -fsSLo /usr/share/keyrings/brave-browser-archive-keyring.gpg https://brave-browser-apt-release.s3.brave.com/brave-browser-archive-keyring.gpg && \
	curl -fsSLo /etc/apt/sources.list.d/brave-browser-release.sources https://brave-browser-apt-release.s3.brave.com/brave-browser.sources && \
	apt update && apt install -y brave-browser

Configure Time Zone, Locales, and Console Display

Configure time zone.

        
dpkg-reconfigure tzdata
# --- Or manually set time zone with symlink ---
ln -sf /usr/share/zoneinfo/Asia/Jakarta /etc/localtime

Configure locales.

        
        
        
    
dpkg-reconfigure locales
# --- Or manually set locales ---
## Edit locale generator file.
vim /etc/locale.gen
## Search and uncomment `en_US.UTF-8 UTF-8` section

## Generate locale
locale-gen

## Create locale config file
echo "LANG=en_US.UTF-8" > /etc/locale.conf
echo "KEYMAP=us" > /etc/vsconsole.conf

Configure console display to Terminus with 16x32 font size.

        
dpkg-reconfigure console-setup
# Set console display to Terminus with 16x32

Setting Hostname and Hosts File

Setting the /etc/hostname file.

        
echo "ubzz" > /etc/hostname

Setting the /etc/hosts file.

sed -i "2i 127.0.1.1       ubzz" /etc/hosts

Create New User

        
useradd -m whyuhurtz -s /bin/bash -G sudo,audio,video,input
passwd whyuhurtz

Network

        
        
        
    
# Make sure network-manager utils was installed.
apt install -y network-manager

# Create a file to configure the network via NetworkManager (nmcli)
cat <<EOF > /etc/netplan/network-manager.yaml
network:
  version: 2
  renderer: NetworkManager
EOF

GRUB Boot Loader Config

Regenerate the /etc/default/grub config file.

        
# --- BIOS legacy ---
grub-install /dev/sda
# --- UEFI ---
grub-install --target=x86_64-efi --efi-directory=/boot --bootloader-id=Ubuntu

update-grub

Reboot into The New System

        
exit # from chroot environment
umount /mnt
reboot

Note: Make sure all of the configurations in your /etc/fstab file are correct before rebooting.

Configure ZRAM Swap

Note: After successfully getting a new Ubuntu setup, log in with the regular user that we’ve created before.

Check internet connection.

ping ubuntu.com

Install the zram swap management utility.

        
# Install zram-tools
sudo apt install -y zram-tools

Configure zram swap.

        
        
        
    
# Set zram to use the zstd algorithm compression,
# and use 30% of all free RAM space
cat <<EOF > /etc/default/zramswap
ALGO=zstd
PERCENT=30
EOF

Enable zramswap service.

sudo systemctl enable zram

Note: If you’re running a different OS on a separate SSD, you need to enable the bootable flag again.

        
sudo parted /dev/nvme0n1
set 1 boot on
exit
sudo udevadm settle; sudo systemctl daemon-reload

Reboot the system to apply the zram swap configuration.

sudo reboot

Install GNOME Desktop Environment

Note: You’ve 2 options here, install Ubuntu minimal desktop or with full applications installed. I personally choose the fully installed version.

        
# Install full Ubuntu GNOME desktop
sudo apt install -y gdm3 ubuntu-gnome-desktop \
	gnome-tweaks gnome-backgrounds \
	gnome-shell-extension-manager

# Or install a minimal Ubuntu GNOME desktop
sudo apt install -y ubuntu-desktop-minimal

Start Some Services and Reboot

        
        
        
    
# Enable some important services
sudo systemctl enable --now bluetooth.service
sudo systemctl enable --now NetworkManager.service
sudo systemctl enable --now cups.service
sudo systemctl enable --now acpid.service
sudo systemctl enable --now nftables.service

# Reboot the system
sudo reboot

Contents

Install Ubuntu GNOME from Scratch using debootstrap

Pre-installation

Install Required Tools

Console Display

System Clocks

Partitioning

Encrypt Partitions with LUKS2

Formatting Partition

Create BTRFS Subvolumes

Mount Boot Partition and BTRFS Subvolumes

Prepare Chroot Environment

Generate Mounting Table

Chroot into Mounted File System

Install Tools & Software’s

Configure Time Zone, Locales, and Console Display

Setting Hostname and Hosts File

Create New User

Network

GRUB Boot Loader Config

Reboot into The New System

Configure ZRAM Swap

Install GNOME Desktop Environment

Start Some Services and Reboot

References