Hei Android One users,
With the recent Android 10 update for Mi A2 Lite was mostly welcomed with joy for most of the users meanwhile for some a disaster. Numerous users have feedback black screen, not able to boot even to the most conveniently used term as bricked. Well, A/B seamless updates ensure a workable booting system remains on the disk during an over-the-air (OTA) update.
About A/B system
A/B system updates use two sets of partitions referred to as slots (normally slot A and slot B). The system runs from the current slot while the partitions in the unused slot are not accessed by the running system during normal operation. This approach makes updates fault resistant by keeping the unused slot as a fallback: If an error occurs during or immediately after an update, the system can rollback to the old slot and continue to have a working system.
Advantages of A/B partitions
Each slot has a bootable attribute that states whether the slot contains a correct system from which the device can boot. The current slot is bootable when the system is running, but the other slot may have an old version of the system, a newer version, or invalid data. The advantage of having A/B partitions include being able to switch between slots or partitions should you get a bootloop, you can always revert or rollback to an older update or system on the other partition. This is really useful and effective in the case to avoid poor performance due to bugs and even massive battery drain while waiting for the upcoming updates.
Minimal ADB and Fastboot v1.4.3 and install it on your PC/Laptop, preferably on C\:Drive and choose system-wide installation.
Switching or rollback between the partitions
fastboot getvar all
then press Enter, it should return "(bootloader) current-slot:x" value.
fastboot set_active a
fastboot set_active b
fastboot set_active other
That's all to it. Even with the worst-case scenario, it is still manageable just by changing or switching between partition slots, be it stock or custom ROM.
"Solving with simplicity"
In order to fulfill the basic functions of our service, the user hereby agrees to allow Xiaomi to collect, process and use personal information which shall include but not be limited to written threads, pictures, comments, replies in the Mi Community, and relevant data types listed in Xiaomi's Private Policy. By selecting "Agree", you agree to Xiaomi's Private Policy and Content Policy .