808fbf5c7c
<message>Update the _set_golden_from_path function to improve the handling of existing golden image files. Replace the existing unlink logic with a more robust method that safely removes files or broken symlinks using the missing_ok parameter. This change enhances the reliability of the backup upload process by ensuring that stale references are properly cleared before setting a new golden image path.
3.8 KiB
Preparing a backup image for cloud-init (reuse as golden image)
This describes what was done to the device (e.g. 10.20.50.147) so the backup image you take from it is smaller and suitable for deployment as a golden image with cloud-init running on first boot.
1. Size reductions applied
| Action | Effect |
|---|---|
| Removed old kernel (6.12.47) and headers | ~130 MB freed; current kernel 6.12.62 kept |
| APT cache already cleaned | (done earlier) |
| Logs truncated, journal vacuumed | (done earlier) |
| KDE/Plasma removed | (done earlier; ~2.6 GB freed) |
Result: Root filesystem ~7.5 GB used (28% of 29 GB). After taking the backup you can shrink with PiShrink (and optionally compress) for storage and faster deploy; see EMMC-PROVISIONING-GUIDE.md.
2. Cloud-init preparation (so it re-runs after deploy)
These steps were run on the device so that when you restore this image to another reTerminal (or the same one after wipe), the next boot is treated as first boot and cloud-init runs again.
| Step | What was done |
|---|---|
| cloud-init clean | cloud-init clean --logs --machine-id --seed so cloud-init state and seed are removed; next boot is detected as first boot. |
| machine-id | Set to uninitialized; systemd will generate a new unique ID on first boot. |
| SSH host keys | Removed from /etc/ssh/; regenerate_ssh_host_keys.service (or cloud-init) will create new keys on first boot. |
| Hostname | Reset to raspberrypi in /etc/hostname and /etc/hosts; cloud-init can set the real hostname from meta-data or user-data. |
No reboot was performed on the device so you can take the backup immediately.
3. Boot partition (NoCloud)
The device already had cloud-init NoCloud files on the boot partition:
/boot/firmware/user-data/boot/firmware/meta-data/boot/firmware/network-config
When you use this backup as golden image and deploy it:
- Cloud-init will run on first boot and use these files.
- If user-data is set up to download and run your first-boot script (e.g. from the provisioning portal), ensure:
- The FILE_SERVER URL in that script (or in
first-boot.confon the server) is correct for the deployed network (e.g.http://10.20.50.1:5000/files/first-bootor your LXC IP). - The portal has the right first-boot.conf and first-boot assets (sync with
scripts/sync-portal-files-to-lxc.sh).
- The FILE_SERVER URL in that script (or in
If you prefer different user-data / meta-data / network-config (e.g. different hostname, WiFi, or runcmd), either:
- Edit them on the device before taking the backup, or
- After copying the image to the host, mount the boot partition of the image and replace
user-data,meta-data, and optionallynetwork-configwith your versions (see EMMC-PROVISIONING-GUIDE.md).
4. Optional: further size reduction
If you need a smaller image:
- Remove unused locales (e.g. with
localepurgeor by removing locale packages); can save hundreds of MB. - Remove more packages (see DEVICE-REMOVABLE-PACKAGES.md): e.g. CUPS, NFS, development tools, extra fonts.
- PiShrink the backup after imaging (shrinks rootfs and optionally compresses); see the guide above.
5. Taking the backup
- Use your normal Backup flow (e.g. reTerminal in boot mode → dashboard Backup), or
dd/clone the eMMC to a file. - Optionally run PiShrink (and compress) on the host.
- Set the result as golden image in the dashboard if you want to deploy it to other devices.
- On first boot after deploy, cloud-init will run; SSH host keys and machine-id will be new; set hostname and the rest via user-data / meta-data or your first-boot script.