Stick2Metal - Ubuntu 24.04 Offline Installer Builder

Creates a bootable USB/ISO installer that clones a pre-built Ubuntu 24.04 system image to target PCs. Works completely offline - no internet required on target machines.

Overview

Stick2Metal uses a two-stage build process:

1. Packer builds a fully-configured Ubuntu 24.04 UEFI system image with all software pre-installed
2. ISO Builder packages the image into a bootable installer that can be written to USB

Features

• Fully offline installation: All packages pre-installed, no network required on target
• UEFI boot: Modern UEFI firmware support with GPT partitioning
• LVM storage: Root filesystem on LVM for flexibility
• Automatic or manual installation: Boot menu options for both modes
• Automatic disk detection: Selects largest non-USB disk as target
• UUID regeneration: Each installed system gets unique filesystem UUIDs
• Network auto-configuration: DHCP on all ethernet interfaces

Pre-installed Software

Category	Packages
Desktop	XFCE4, LightDM, Xorg
Editor	VS Code (with Rust Analyzer, CodeLLDB, Even Better TOML, HC Zenburn theme)
Development	GCC, G++, Make, CMake, Git, Rust toolchain
Virtualization	QEMU/KVM, Virt-Manager, Podman, Buildah
Networking	Wireshark, tcpdump, nmap, netcat, iperf3, mtr, iftop
Disk Tools	ncdu, duf, squashfs-tools, GParted, LVM2, mdadm, cryptsetup, smartmontools, nvme-cli
Graphics	Mesa drivers, Vulkan, VA-API (Intel/AMD)
Browser	Brave
Utilities	Vim, htop, OpenSSH, Atril (PDF), Gedit

Prerequisites

Install Packer

curl -fsSL https://apt.releases.hashicorp.com/gpg | sudo apt-key add -
sudo apt-add-repository "deb [arch=amd64] https://apt.releases.hashicorp.com $(lsb_release -cs) main"
sudo apt-get update && sudo apt-get install packer

Install QEMU, OVMF, and ISO Tools

sudo apt-get install -y qemu-system-x86 qemu-utils ovmf xorriso squashfs-tools gzip wget

Usage

Step 1: Build the Packer Image

Initialize Packer plugins (first time only):

packer init .

Build the base system image:

./build.sh

This creates output/ubuntu-24.04-autoinstall (~10-15GB) with all packages pre-installed. The build takes 30-60 minutes depending on your system and network speed. A QEMU window will open showing the installation progress.

Step 2: Build the Installer ISO

sudo ./build-installer-iso.sh

This downloads Ubuntu 24.04.3 Server ISO (if not present), compresses the Packer image, and creates ubuntu-installer.iso (~5-6GB).

Step 3: Write to USB Drive

sudo dd if=ubuntu-installer.iso of=/dev/sdX bs=64M status=progress oflag=sync

Replace /dev/sdX with your USB device (use lsblk to identify).

Boot Options

When booting from the installer USB, you'll see three options:

1. Automatic Install - Formats the largest non-USB disk automatically (DANGEROUS - no confirmation!)
2. Manual Install - Boots to shell, run sudo /cdrom/installer/install.sh manually
3. Ubuntu Server Installer - Original Ubuntu installer (requires internet)

Installation Process

The installer performs these steps:

1. Detects and selects target disk (largest non-USB disk)
2. Clones the compressed system image to target
3. Expands partitions to use full disk
4. Regenerates filesystem UUIDs
5. Updates fstab with new UUIDs
6. Regenerates initramfs (critical for boot)
7. Reinstalls GRUB bootloader
8. Configures network for DHCP
9. Sets hostname (auto-generated or prompted)

Default Credentials

Username	ubuser
Password	ubuser

Testing with QEMU

Test the installer ISO in a VM before deploying to real hardware:

# Run the installer (boots from ISO)
./test-vm.sh

# In the live environment, run:
sudo /cdrom/installer/install.sh

# After installation, boot the installed system:
./test-vm.sh --boot

# SSH into the VM (after boot):
ssh -p 2222 ubuser@localhost

# Clean up test files:
./test-vm.sh --clean

Customization

Autoinstall Configuration

Edit http/user-data to modify the base system:

• Username/password
• Hostname
• Keyboard layout
• Disk partitioning scheme (EFI + Boot + LVM)
• Network configuration

Pre-installed Software

Edit ubuntu.pkr.hcl provisioners to add/remove packages installed in the golden image.

Installer Behavior

Edit build-installer-iso.sh to modify:

• Target disk selection logic
• Post-install configuration
• Network settings

Disk Layout

The installed system uses this partition scheme:

Partition	Size	Type	Mount Point
EFI System	512MB	FAT32	/boot/efi
Boot	1GB	ext4	/boot
LVM PV	Remaining	LVM	-
└─ vg0/root	100% of VG	ext4	/