Azure Sphere SDK: When does the running OS allow a new OS update to be deferred by the application.

Question

I have read through https://learn.microsoft.com/en-us/azure-sphere/app-development/device-update-deferral?view=azure-sphere-integrated and it is still not clear how the running OS determines if it will allow the application an opportunity to defer a new OS update.

The specific scenario of concern is an Azure Sphere enabled product that is offline (in a box on a shelf) at a customer site. While the product is offline Microsoft releases a new Sphere OS update. Two weeks later the product is brought online by the customer. The running OS on the product downloads the new OS update.... Is the application still given the opportunity to defer the update up to 24 hours? Or is deferral not allowed since the OS update has been effectively deferred by two weeks because the product was offline?

Answer 1

Hello,

Thank you for posting the question!

The deferment API limits start from the time that the device is made aware of the update requirement. In the case you outline below, the offline device will come online, realize there is an OS update, consult the application (if it has registered for deferment notifications), and allow the application to defer the update for up to 24 hours.

This API is designed for applications to ensure the device is in a "safe" state before update begins, which is why the period starts from the time the device is aware of it.

Hope this answer helps. Please let us know if you have any questions.