11 KiB

Raw Blame History

How to create custom Ubuntu live from scratch

Prerequisites (GNU/Linux Debian/Ubuntu)

Install applications we need to build the environment.

sudo apt-get install \
    debootstrap \
    squashfs-tools \
    xorriso \
    grub-pc-bin \
    grub-efi-amd64-bin \
    mtools

mkdir $HOME/live-ubuntu-from-scratch

Bootstrap and Configure Ubuntu

sudo debootstrap \
    --arch=amd64 \
    --variant=minbase \
    bionic \
    $HOME/live-ubuntu-from-scratch/chroot \
    http://us.archive.ubuntu.com/ubuntu/

sudo mount --bind /dev $HOME/live-ubuntu-from-scratch/chroot/dev

sudo mount --bind /run $HOME/live-ubuntu-from-scratch/chroot/run

Access chroot environment

sudo chroot $HOME/live-ubuntu-from-scratch/chroot

Configure mount points

mount none -t proc /proc

mount none -t sysfs /sys

mount none -t devpts /dev/pts

export HOME=/root

export LC_ALL=C

Set a custom hostname
```
echo "ubuntu-live" > /etc/hostname
```

Configure apt sources.list

cat <<EOF > /etc/apt/sources.list
deb http://us.archive.ubuntu.com/ubuntu/ bionic main restricted universe multiverse 
deb-src http://us.archive.ubuntu.com/ubuntu/ bionic main restricted universe multiverse 

deb http://us.archive.ubuntu.com/ubuntu/ bionic-security main restricted universe multiverse 
deb-src http://us.archive.ubuntu.com/ubuntu/ bionic-security main restricted universe multiverse 

deb http://us.archive.ubuntu.com/ubuntu/ bionic-updates main restricted universe multiverse 
deb-src http://us.archive.ubuntu.com/ubuntu/ bionic-updates main restricted universe multiverse    
EOF

Update indexes packages
```
apt-get update
```
Install systemd
```
apt-get install -y systemd-sysv
```

Configure machine-id and divert

dbus-uuidgen > /var/lib/dbus/machine-id

dpkg-divert --local --rename --add /sbin/initctl

ln -s /bin/true /sbin/initctl

ln -fs /var/lib/dbus/machine-id /etc/machine-id

Install packages needed for Live System

apt-get install -y \
    ubuntu-standard \
    casper \
    lupin-casper \
    discover \
    laptop-detect \
    os-prober \
    network-manager \
    resolvconf \
    net-tools \
    wireless-tools \
    wpagui \
    locales \
    linux-generic

Graphical installer

apt-get install -y \
    ubiquity \
    ubiquity-casper \
    ubiquity-frontend-gtk \
    ubiquity-slideshow-ubuntu \
    ubiquity-ubuntu-artwork

Install window manager

apt-get install -y \
    plymouth-theme-ubuntu-logo \
    ubuntu-gnome-desktop \
    ubuntu-gnome-wallpapers

Install usefull applications

apt-get install -y \
    clamav-daemon \
    terminator \
    apt-transport-https \
    curl \
    vim \
    nano

Install Visual Studio Code

Download and install the key

curl https://packages.microsoft.com/keys/microsoft.asc | gpg --dearmor > microsoft.gpg

install -o root -g root -m 644 microsoft.gpg /etc/apt/trusted.gpg.d/

echo "deb [arch=amd64] https://packages.microsoft.com/repos/vscode stable main" > /etc/apt/sources.list.d/vscode.list

rm microsoft.gpg

Then update the package cache and install the package using:
```
apt-get update

apt-get install -y code
```

Install Google Chrome

Download and install the key

wget -q -O - https://dl-ssl.google.com/linux/linux_signing_key.pub | sudo apt-key add -

Add the key to the repository

echo "deb http://dl.google.com/linux/chrome/deb/ stable main" > /etc/apt/sources.list.d/google-chrome.list

Finally, Update repository and install Google Chrome.

apt-get update

apt-get install google-chrome-stable

Install Java JDK 8

apt-get install -y \
    openjdk-8-jdk \
    openjdk-8-jre

Remove unused applications

apt-get purge -y \
    transmission-gtk \
    transmission-common \
    gnome-mahjongg \
    gnome-mines \
    gnome-sudoku \
    aisleriot \
    hitori

Remove unused packages
```
apt-get autoremove -y
```

Reconfigure packages

Generate locales
```
dpkg-reconfigure locales
```
Reconfigure resolvconf
```
dpkg-reconfigure resolvconf
```

Configure network-manager

cat <<EOF > /etc/NetworkManager/NetworkManager.conf
[main]
rc-manager=resolvconf
plugins=ifupdown,keyfile
dns=dnsmasq

[ifupdown]
managed=false
EOF

Reconfigure network-manager
```
dpkg-reconfigure network-manager
```

Cleanup the chroot environment

If you installed software, be sure to run
```
rm /var/lib/dbus/machine-id
```

Remove the diversion

rm /sbin/initctl

dpkg-divert --rename --remove /sbin/initctl

Clean up

apt-get clean

rm -rf /tmp/* ~/.bash_history

umount /proc

umount /sys

umount /dev/pts

export HISTSIZE=0

exit

Unbind mount points

sudo umount $HOME/live-ubuntu-from-scratch/chroot/dev

sudo umount $HOME/live-ubuntu-from-scratch/chroot/run

Create the CD image directory and populate it

Access build directory
```
cd $HOME/live-ubuntu-from-scratch
```

Create directories

mkdir -p image/{casper,isolinux,install}

Copy kernel images

sudo cp chroot/boot/vmlinuz-**-**-generic image/casper/vmlinuz

sudo cp chroot/boot/initrd.img-**-**-generic image/casper/initrd

Copy memtest binary

sudo cp chroot/boot/memtest86+.bin image/install/memtest

Grub configuration

Access build directory
```
cd $HOME/live-ubuntu-from-scratch
```

Create image/isolinux/grub.cfg

cat <<EOF > image/isolinux/grub.cfg

search --set=root --file /ubuntu

insmod all_video

set default="0"
set timeout=30

menuentry "Try Ubuntu without installing" {
   linux /casper/vmlinuz boot=casper quiet splash ---
   initrd /casper/initrd
}

menuentry "Install Ubuntu" {
   linux /casper/vmlinuz boot=casper only-ubiquity quiet splash ---
   initrd /casper/initrd
}

menuentry "Check disc for defects" {
   linux /casper/vmlinuz boot=casper integrity-check quiet splash ---
   initrd /casper/initrd
}

menuentry "Test memory" {
   linux /install/memtest
}
EOF

Create manifest

Access build directory
```
cd $HOME/live-ubuntu-from-scratch
```

Generate manifest

sudo chroot chroot dpkg-query -W --showformat='${Package} ${Version}\n' | sudo tee image/casper/filesystem.manifest

sudo cp -v image/casper/filesystem.manifest image/casper/filesystem.manifest-desktop

sudo sed -i '/ubiquity/d' image/casper/filesystem.manifest-desktop

sudo sed -i '/casper/d' image/casper/filesystem.manifest-desktop

sudo sed -i '/discover/d' image/casper/filesystem.manifest-desktop

sudo sed -i '/laptop-detect/d' image/casper/filesystem.manifest-desktop

sudo sed -i '/os-prober/d' image/casper/filesystem.manifest-desktop

Compress the chroot

Access build directory
```
cd $HOME/live-ubuntu-from-scratch
```

Create squashfs

sudo mksquashfs chroot image/casper/filesystem.squashfs

Write the filesystem.size

printf $(sudo du -sx --block-size=1 chroot | cut -f1) > image/casper/filesystem.size

Create diskdefines

Access build directory
```
cd $HOME/live-ubuntu-from-scratch
```

Create file image/README.diskdefines

cat <<EOF > image/README.diskdefines
#define DISKNAME  Ubuntu from scratch
#define TYPE  binary
#define TYPEbinary  1
#define ARCH  amd64
#define ARCHamd64  1
#define DISKNUM  1
#define DISKNUM1  1
#define TOTALNUM  0
#define TOTALNUM0  1
EOF

Recognition as an Ubuntu from scratch

Access build directory
```
cd $HOME/live-ubuntu-from-scratch
```
Create an empty file named "ubuntu" and a hidden ".disk" folder.
```
touch image/ubuntu

mkdir image/.disk
```

Create ISO Image for a LiveCD (BIOS + UEFI)

Access image directory

cd $HOME/live-ubuntu-from-scratch/image

Create a grub UEFI image

grub-mkstandalone \
   --format=x86_64-efi \
   --output=isolinux/bootx64.efi \
   --locales="" \
   --fonts="" \
   "boot/grub/grub.cfg=isolinux/grub.cfg"

Create a FAT16 UEFI boot disk image containing the EFI bootloader

(
   cd isolinux && \
   dd if=/dev/zero of=efiboot.img bs=1M count=10 && \
   sudo mkfs.vfat efiboot.img && \
   mmd -i efiboot.img efi efi/boot && \
   mcopy -i efiboot.img ./bootx64.efi ::efi/boot/
)

Create a grub BIOS image

grub-mkstandalone \
   --format=i386-pc \
   --output=isolinux/core.img \
   --install-modules="linux normal iso9660 biosdisk memdisk search tar ls" \
   --modules="linux normal iso9660 biosdisk search" \
   --locales="" \
   --fonts="" \
   "boot/grub/grub.cfg=isolinux/grub.cfg"

Combine a bootable Grub cdboot.img

cat /usr/lib/grub/i386-pc/cdboot.img isolinux/core.img > isolinux/bios.img

Generate sha256sum.txt

sudo /bin/bash -c "(find . -type f -print0 | xargs -0 sha256sum | grep -v "\./sha256sum.txt" > sha256sum.txt)"

Create iso from the image directory using the command-line

sudo xorriso \
   -as mkisofs \
   -iso-level 3 \
   -full-iso9660-filenames \
   -volid "Ubuntu from scratch" \
   -eltorito-boot \
      boot/grub/bios.img \
      -no-emul-boot \
      -boot-load-size 4 \
      -boot-info-table \
      --eltorito-catalog boot/grub/boot.cat \
   --grub2-boot-info \
   --grub2-mbr /usr/lib/grub/i386-pc/boot_hybrid.img \
   -eltorito-alt-boot \
      -e EFI/efiboot.img \
      -no-emul-boot \
   -append_partition 2 0xef isolinux/efiboot.img \
   -output "../ubuntu-from-scratch.iso" \
   -graft-points \
      "." \
      /boot/grub/bios.img=isolinux/bios.img \
      /EFI/efiboot.img=isolinux/efiboot.img

11 KiB Raw Blame History