how to cancel the limit of version in ncs sdk when ota?

[pipixia_1_1]

I am developing my product using the desktop app in the NCS SDK. I found that during OTA, it can only upgrade from a lower version to a higher version. This means that when my users upgrade to a problematic version, they can't roll back, which is quite troublesome. Is there any way to remove this restriction?

[Priyanka]

Hi,

Which SDK version and Nordic chip are you using here?

You could disable the software downgrade prevention by disabling CONFIG_MCUBOOT_DOWNGRADE_PREVENTION=n and SB_CONFIG_MCUBOOT_MODE_OVERWRITE_ONLY=n (for SDK version>2.7.0 and using Sysbuild), See the documentation here.

If you are optimizing for production, you might want to leave downgrade prevention enabled for security. Also, please see that removing the version-checking mechanism comes with a security trade-off since downgrades might introduce vulnerabilities that newer versions have fixed.

Regards,

Priyanka

[pipixia_1_1]

sdk is ncs V2.6,and the chip is nrf52840

[Priyanka]

Then you could take a look at this: https://docs.nordicsemi.com/bundle/ncs-2.6.0/page/nrf/config_and_build/bootloaders/bootloader_downgrade_protection.html#software-based-downgrade-protection similar to the documentation I attached previously.