OTA Update on a Rooted Device

The installation of OTA updates often fails if the device has been rooted. Though it's still possible – without data loss. This guide shows how, using TWRP and Magisk.

IMPORTANT: Before you start backup everything that's important! Proceed at own risk!

Prerequisite

The Update file of the version that's already running on the device (NOT the update you want to install)
TWRP for your device
Magisk
ADB and Fastboot inclusive developer mode the device

Don't forget to check the checksums of all files.

Doing the update isn't that difficult: Reset some system partitions, install OTA, refresh TWPR and Magisk, done. There are two versions of this guide: The short version is just a list of steps, while the long version contains each step and the commands necessary.

Short Version

Download the Update current installed
Enable USB Debugging
Boot to Bootloader
Flash recovery, system and boot images
Reboot
Flash TWRP
Boot to Recovery
Install Magisk
Reboot

Long Version

At first double check your backups and the prerequisites listed above.

Preparation

Copy Magisk to your device

Copy (or download) Magisk Zip to your device. It doesn't matter if it's on the internal or SD memory, just place it somewhere you can find it again later. You can do this step at any later time too.

Stock files of current running version

Download the update file for the version running on your device, not the version you want to install. Given you are running on v1.2.3 and want to update to v1.2.4, you need the v1.2.3 file.

Unpack the downloaded file, you need: recovery.img, system.img and boot.img.

Enable USB Debugging

Plug the divce to your computer throuth USB and and enable USB Debugging on the device.

Flash System Images

Open a terminal and use these commands to flash the necessary partitions (don't type the $).

# Check if device is recognized
> adb devices

# Boot into bootloader
> adb reboot bootloader

# Check device again in Bootloader
> fastboot devices

# Flash recovery image
> fastboot flash recovery recovery.img

# Flash system image
> fastboot flash system system.img

# Flash boot image
> fastboot flash boot boot.img

# Reboot device
> fastboot reboot

Install OTA

Install the OTA as usual on the device. The update will reboot automatically. Once this is done check that the installed version is correct and your system is up to date.

Install TWRP

Flash TWRP using ADB. The image typically has a differnt name, for simplification TWRP.img is used here.

# Check if device is recognized
> adb devices

# Boot into bootloader
> adb reboot bootloader

# Check device again in Bootloader
> fastboot devices

# Flash TWRP
> fastboot flash recovery TWRP.img

# Reboot device
> fastboot reboot

Boot into TWRP

When the last command restarts the device, use the Volume Keys to navigate. Select boot into "Recovery". TWRP will show up then.

Install Magisk

From the TWRP menu select "Install" and install the Magisk Zip. Reboot afterwards.

Note: It's a good chance to clear the Dalvik-Cache here, but that's fully optional.

Done

Once back in your system make sure everything works fine, you are running the latest version and root is enabled. Just one last step: Disable USB Debugging.

That's it!

3.6 KiB Raw Blame History Unescape Escape