Creation of iso

Prerequisites:

  1. Installed Linux System: Ensure you have a working Debian or Ubuntu system installed on your arm64 device.
  2. Extra Packages: Have ubiquity or live-installer installed. For this example, we’ll focus on using ubiquity as it’s more commonly used.
  3. Required Tools: Make sure you have tools like debootstrap, mkbootimg, mkisofs, and genisoimage installed.

Steps to Create a Bootable ISO:

Step 1: Prepare Your System

First, ensure your system is up-to-date:

sudo apt update
sudo apt full-upgrade

Step 2: Install Required Packages

If you haven’t installed ubiquity yet, do so:

sudo apt install ubiquity

Ensure other necessary tools are installed:

sudo apt install debootstrap mkbootimg mkisofs genisoimage

Step 3: Create a Directory for Your ISO Contents

Create a temporary directory to hold your live system’s contents:

sudo mkdir -p /tmp/live-iso

Step 4: Use debootstrap to Create a Base System (Optional)

If you’re starting from scratch or want a minimal base, you can use debootstrap. This step is optional if you’re using an existing system:

sudo debootstrap --arch arm64 --no-install-recommends buster /tmp/live-iso/debootstrap https://deb.debian.org/debian buster main

Step 5: Copy Existing System to Live Directory

If you’re not using debootstrap, copy your existing system into the live directory. This involves chrooting into your existing system and then copying it. However, for simplicity and to avoid potential issues with permissions and paths, let’s focus on directly creating an ISO from your current system using ubiquity.

Step 6: Configure and Build the ISO

  1. Identify your current kernel and initrd: ls /boot

Create a directory structure for your live ISO:

sudo mkdir -p /tmp/live-iso/boot

Copy the kernel and initrd to the live ISO directory:

sudo cp /boot/vmlinuz-$(uname -r) /tmp/live-iso/boot/vmlinuz
sudo cp /boot/initrd.img-$(uname -r) /tmp/live-iso/boot/initrd.img

Create a preseed file (if needed) for automated installations. This step can be skipped if you’re manually installing.

sudo nano /tmp/live-iso/preseed.cfg

Example content:

d-i debian-installer/locale string en_US.UTF-8
d-i console-setup/ask_detect boolean false
d-i console-setup/layout string us
d-i mirror/country string manual
d-i mirror/http/hostname string http.debian.org
d-i mirror/http/directory string /debian
d-i mirror/http/proxy string
d-i mirror/country string manual
d-i preseed/late_command string in-target sed -i 's/^#PermitRootLogin.*/PermitRootLogin yes/' /target/etc/ssh/sshd_config

Create the ISO:

For ubiquity, use:

sudo apt install live-boot
sudo mkdir -p /tmp/iso
sudo cp -rT /usr/share/ubiquity /tmp/iso
sudo cp /tmp/live-iso/boot/vmlinuz /tmp/iso/boot/vmlinuz
sudo cp /tmp/live-iso/boot/initrd.img /tmp/iso/boot/initrd.img
sudo cp /tmp/live-iso/preseed.cfg /tmp/iso/preseed.cfg
sudo mkisofs -o /tmp/debian-live-arm64.iso -b isolinux -c boot.catalog -r -T /tmp/iso
  1. Adjust paths and names as necessary.

Step 7: Make the ISO Bootable on arm64

The process to make an ISO bootable can vary depending on the specific arm64 device. Typically, you might need to:

  • Convert the ISO to a .img format or directly create a bootable image.
  • Use tools like mkbootimg to create a bootable image: mkbootimg --kernel /tmp/live-iso/boot/vmlinuz --ramdisk /tmp/live-iso/boot/initrd.img --output /tmp/arm64-live.img --pagesize 2048
  • Adjust parameters based on your device’s requirements.

Final Steps:

  • Transfer the generated ISO or image to your installation media (SD card, USB drive, etc.).
  • Boot your arm64 device from the media.

Note: This guide provides a general overview. The process can be complex and might require device-specific adjustments. Always backup your data before proceeding. Testing the live environment and installation on a non-production device first is highly recommended.

Reasoning:
To create a bootable ISO from an installed Linux system using Ubiquity or live-installer, follow these steps. Since you’re working with an arm64 system and aiming to create a medium for installing Debian or Ubuntu, the process involves several detailed steps.

Step 1: Prepare Your System

First, ensure your installed Linux system is up to date. Open a terminal and run:

sudo apt update
sudo apt full-upgrade

Step 2: Install Necessary Packages

You’ll need to install ubiquity or live-installer along with other necessary packages. For Ubuntu-based systems, ubiquity is the recommended choice. For Debian, you might consider live-installer or using ubiquity if it’s available and compatible.

For Ubuntu-based systems (including Ubuntu itself):

sudo apt install ubiquity ubiquity-frontend-gtk

For Debian, if you choose to use live-installer:

sudo apt install live-installer

Additionally, you’ll need squashfs-tools and genisoimage (or xorriso for more advanced options) for creating the ISO:

sudo apt install squashfs-tools genisoimage

Step 3: Configure the Live System

Before creating the ISO, you might want to customize your live system. This could involve installing additional packages, configuring the network settings, or modifying the desktop environment. Remember, any changes made to the system will be included in the live ISO.

Step 4: Create the Live ISO

The process of creating the ISO involves several steps, including creating a squashfs of your system, then using this squashfs to generate the ISO.

  1. Create a Squashfs:

First, you need to create a squashfs image of your root filesystem. It’s a good idea to exclude certain directories like /tmp, /proc, /dev, /sys, and /run because they’re either temporary or generated at boot time.

sudo rm -rf /tmp/livecd
sudo mkdir /tmp/livecd
sudo mksquashfs / /tmp/livecd filesystem.squashfs -e /tmp /proc /dev /sys /run
  1. Prepare the ISO Structure:

Create a directory structure for your live CD. You’ll need an isolinux directory for BIOS booting and possibly an EFI directory for UEFI booting.

sudo mkdir -p /tmp/livecd/{isolinux,EFI}

For UEFI support on arm64, you might need to ensure you have the appropriate bootloader configured. This could involve copying the necessary bootloader files into the EFI directory.

  1. Copy Necessary Files:

Copy the filesystem.squashfs you created into the root of your live CD structure, and ensure you have the necessary boot files in place. For isolinux, you’ll need isolinux.bin and a config file (isolinux.cfg or txt.cfg).

sudo cp /tmp/livecd/filesystem.squashfs /tmp/livecd/

You’ll need to configure isolinux.cfg or txt.cfg to point to your squashfs and kernel. An example txt.cfg might look like:

default live
label live
  menu label ^Start Debian Live
  kernel /boot/vmlinuz
  append initrd=/boot/initrd.img boot=live config quiet splash --

Ensure the kernel and initrd paths match your system’s.

  1. Generate the ISO:

Finally, use genisoimage to create the ISO. Make sure to include the necessary boot information.

sudo genisoimage -o /tmp/debian-live.iso -r -J -no-emul-boot -boot-load-size 4 -boot-info-table --eltorito-kernel isolinux/isolinux.bin --eltorito-catalog isolinux/boot.cat /tmp/livecd

Or, if you prefer xorriso for more flexibility:

sudo xorriso -as mkisofs -r -J -no-emul-boot -boot-load-size 4 -boot-info-table --eltorito-kernel isolinux/isolinux.bin --eltorito-catalog isolinux/boot.cat -output /tmp/debian-live.iso /tmp/livecd

Step 5: Test Your ISO

Before distributing or using your ISO for installations, it’s crucial to test it in a virtual machine (like QEMU or VirtualBox) to ensure it boots correctly and installs as expected.

This process can be complex and is highly dependent on the specific versions of Debian or Ubuntu you’re working with, as well as the arm64 architecture. Always refer to the latest documentation for your distribution and be prepared to troubleshoot issues as they arise.

Given the complexity and the need for precise, distribution-specific steps, consider consulting the official documentation for Ubuntu or Debian for creating live CDs, as the process might have been updated or simplified since this guide was written.

Creating a bootable ISO from an installed Linux system, especially on an arm64 architecture, involves several steps. This guide assumes you are using a Debian or Ubuntu system and have ubiquity or live-installer as an extra package installed. The process might slightly vary depending on which installer you choose to use.