Question about in-place updates and power-failure resilience

[tmordeko]

Hi,

These are more like a questions:

1. Does this delta OTA implementation support in-place updates (using a single partition where the new firmware is built directly over the old firmware using the patch) or does it require dual partitions ("A/B updates") to accommodate the old firmware while the new firmware is built separately from the patch?

2. Does it provide resiliency against power failures during patching, meaning that if a power failure occurs, can it the update process resume safely after restart ?

Thanks in advance,
Tzvika

[kstribrnAmzn]

Thanks for the questions @tmordeko!

1. This library simplifies the OTA file transfer from AWS along with sequencing the various underlying MCU calls to perform an update. If I remember correctly there is nothing in this package which should restrict you from doing in-place updates if your MCU supports it.

2. This library does not persist the state of the OTA to a durable storage medium (flash, disk, etc.) so a power outage would cause the OTA process to restart. You'll also want to check your underlying MCU functionality which is used for switching firmware, storing blocks, etc. to verify they have power resiliency.

One note - in place updates are likely to make power resiliency more challenging.