#Tersler disk image

build-image.sh builds a ready-to-boot Ubuntu 24.04 server image for the SSD. After dd, the rig boots straight into SSH; no installer, no desktop, no Xorg/Wayland, no snapd.

#Build (on any Linux PC with KVM, no root needed)

image/build-image.sh

• Customizes Ubuntu's official cloud image (noble-server-cloudimg-amd64.img, checksum verified) in a QEMU/KVM VM, then test-boots the result with UEFI on a 40 GB virtual disk and logs in over SSH.
• Output: image/out/tersler.img.zst (+ .sha256) and image/out/console-password.txt. Both are git-ignored.
• Peak disk usage ~7 GB; the script checks first. Elsewhere: OUT=/other/disk image/build-image.sh.
• Settings via environment: RIG_HOSTNAME (tersler), RIG_USER (you), RIG_SSH_KEY (~/.ssh/id_ed25519.pub), RIG_TZ (Europe/Berlin), RIG_KEYMAP (de), IMG_SIZE (6G).

#What's in the image

• Ubuntu 24.04 server (cloud image base) with linux-generic, which includes linux-modules-extra, the hardware drivers the cloud kernel leaves out.
• User $RIG_USER: SSH key login only, passwordless sudo. The password in console-password.txt works on the local console only.
• DHCP on every wired port (en*), IPv4 + IPv6; mDNS via avahi.
• This project in ~/tersler.
• Boot console on the VGA (tty1) and on ttyS0; a 3 s GRUB menu.
• GPT with an EFI partition and a BIOS boot partition: boots in UEFI and legacy mode.
• First boot on the rig: cloud-init (local seed only, no network datasource, network config untouched) grows the root partition to the whole SSD and generates new SSH host keys. Nothing else.

#Write it to the SSD

Connect the SSD to a PC (USB-SATA adapter or a spare SATA port). Check the device name twice; dd overwrites whatever you point it at:

lsblk -o NAME,SIZE,MODEL,TRAN

zstdcat image/out/tersler.img.zst | sudo dd of=/dev/sdX bs=4M conv=fsync status=progress

Writes ~6 GB. Don't mount it afterwards; just put the SSD into the rig.

#First boot

1. BIOS: boot from the SSD (UEFI). Above 4G Decoding as in hardware-notes.md.
2. Network cable into one of the Intel ports (not the management port).

3. After ~1 min:

   ssh tersler.local

   If mDNS doesn't resolve, look up the DHCP lease in your router.

4. Then follow TODO.md: cd ~/tersler && sudo ./install/install.sh.

Don't leave a second disk with the same image plugged in: both carry the filesystem label cloudimg-rootfs.