A/B Updates and Over-the-Air Delivery

10 Lektionen in dieser Stufe

1. Update Strategies Compared: Packages, Containers and Images
   Weigh each method by atomicity, size and rollback. · Lab: Score three strategies against your product's requirements in a decision table.
2. Partition Layouts for A/B Systems
   Design slots for boot, root and persistent data. · Lab: Partition a card with two boot and two root slots plus a shared data partition.
3. The tryboot Mechanism and autoboot.txt
   Use the Pi firmware's one-shot trial boot to test a new slot. · Lab: Trigger a tryboot into slot B and observe the fallback when it is not confirmed.
4. Building and Installing Update Bundles with RAUC
   Package a root filesystem image and install it to the inactive slot. · Lab: Configure the update client, build a bundle and install it to slot B.
5. Signing Updates and Verifying Them on the Device
   Protect the update channel with a key hierarchy. · Lab: Create a signing key and certificate chain and show an unsigned bundle being rejected.
6. Health Checks and Automatic Rollback
   Define what "working" means and commit an update only when it is met. · Lab: Write a health-check service that marks the slot good, then ship a release that fails it.
7. Bootloader EEPROM Updates in the Field
   Update bootloader firmware and configuration safely on remote units. · Lab: Stage a bootloader update with a pinned release and verify the result after reboot.
8. Hosting an Update Server and Polling Client
   Publish releases and let devices fetch them on their own schedule. · Lab: Serve bundles over HTTPS with a manifest and write a client that polls with jitter.
9. Delta Updates and Bandwidth Budgets
   Reduce transfer size for metered and slow links. · Lab: Compare full and delta bundle sizes and estimate monthly data per device.
10. Canary Groups and Staged Rollouts
    Release to a few devices first and widen only when healthy. · Lab: Roll a release to one device, then all, with an automatic halt on failure.

Abschlussprojekt

A two-slot system that downloads a signed update, boots it on trial, confirms its own health and rolls back automatically when you ship a deliberately broken release.

Teile für diese Stufe

• 2 × Raspberry Pi 5, Pi 4 or Compute Module set from earlier levels
• 2 × microSD card 32 GB or eMMC module
• 1 × USB to TTL serial adapter (3.3 V)
• 1 × Second computer or Pi as update server

In jeder Lektion legst du die passenden Teile direkt in den Warenkorb. Raspberry Pi →