Google has finally started to provide their users with monthly security updates.

This is good news for everyone, but more work for those of us who have rooted phones, as the OTA updates check if the system was modified before installing, and refuse to install if it was.

For rooted users, the solution, although a little bit extensive, is quite easy – flashing all the system files, and re-rooting the device.

The following is needed before starting:

Notice: The following procedure will keep all user data (some system settings are reset), but as with all system upgrades, a backup is advisable. Any and all damage you might  do to your device and your data is your full responsibility. I’m assuming anyone attempting this will already have experience using fastboot and adb.

Before starting make sure that USB debugging is enabled and that the computer you are going to use is authorised.

After extracting the factory image and booting into Fastboot Mode (usually Volume Down + Power), the following steps should be executed:

fastboot flash bootloader bootloader-angler-angler-xx.xx.img
fastboot reboot-bootloader
fastboot flash radio radio-angler-angler-xx.xx.img
fastboot reboot-bootloader
fastboot flash boot boot.img
fastboot erase cache
fastboot flash cache cache.img
fastboot flash recovery recovery.img
fastboot flash system system.img
fastboot flash vendor vendor.img

The system should now be able to boot, but it will be un-rooted.

To root it, the following should be executed after entering Fastboot Mode.

fastboot flash recovery twrp-2.8.7.2-angler.img
fastboot reboot-bootloader

After this, enter Recovery Mode (through the Fastboot Mode menu) and flash the SuperSU zip file (if needed, adb push can be used to upload the file). After rebooting the phone should be rooted and running the latest version of Android.

This was successfully tested on 2015.12.08, upgrading from Android 6.0.0 to 6.0.1 on the following devices :

  • Nexus 6p
  • Nexus 6
  • Nexus 5