Direct OSTree updates between Torizon 4.0 and 5.1?

We have fielded several Torizon 4.0 Apalis iMX6/Ixora devices with limited physical access, except they have ssh access. Consequently a recovery/Easy Install cycle is more difficult than a direct OSTree update.

We’d like to upgrade these machines to Torizon 5.1. We’ve had some success upgrading one version of Torizon 4.0 to another version of Torizon 4.0 that has the same u-boot configuration. (By version, I mean different custom BSP builds.)

I’m aware that BSP 4.0 has been deferred (hence the move to Torizon 5) but I’m curious if it would be worth trying a direct OSTree update to Torizon 5.1 on a machine running a recent 4.0?

Greetings @deltamike,

While we haven’t explicitly tried doing an update form 4.0 to 5.1. I am fairly confident it won’t “just work”. We’ve made a multitude of changes from 4.0 to 5.1. Some of those changes even touched how updates are done on the system. I imagine the update compatibility is completely broken between these version.

Also as a side note we with OTA/OSTree updates we only really guarantee update compatibility between same/similar versions. Major revision changes like 4.X to 5.X are not generally expected to work.

Best Regards,
Jeremias