How to Update Nexus 9 to Android 5.0 LRX21L Lollipop via Factory Image and Install Chainfire's One-Click Root

Nexus 9 owners are in for a double treat, as Google has officially released its first Android 5.0 Lollipop update with build number LRX21L via factory image, and Chainfire has unleashed his popular one-click rooting tool, CF Auto Root, for the device.

Users are advised to unlock the bootloader before delving into the process of installing the latest Android 5.0 Lollipop update on their nexus device as the update is based on stock factory image.

Note: As this is a full firmware, it does not require you to install any base Android firmware before updating to Lollipop.

IBTimes UK reminds readers that it will not be held liable for any damage to device during or after Android 5.0 firmware upgrade. Users are advised to proceed at their own risk.

Pre-requisites

• The instructions given in this guide are meant for the Nexus 9 model only. Verify device model number by navigating to Settings > About Tablet as installing this firmware on incorrect variants might brick the device.
• Ensure the tablet has at at least 80% battery charge to prevent unexpected device shutdown (due to battery drain) while installing the ROM.
• Back up data and settings using a recommended custom recovery tool, like ClockworkMod (CWM) or TWRP, as it creates a complete image of the existing phone setup. In Recovery, choose Backup and Restore and tap Backup.
• Verify correct USB drivers for the phone are installed on the computer (download Nexus 9 USB drivers).
• Ensure that the device is rooted with CWM or TWRP recovery installed and its bootloader is unlocked.

Interested users who want to upgrade their device to the latest Android firmware can follow the step-by-step guide provided below, courtesy of Team Android:

Steps to Update Nexus 9 to Android 5.0 LRX21L Lollipop via Factory Image

Step 1 - Download Android 5.0 Factory Image for Nexus 9 on your computer.

Step 2 – Connect the Nexus 9 to your computer via USB cable.

Step 3 - Ensure Fastboot is configured and properly installed on your computer. (click to see guide).

Step 4 – Power off your tablet and boot it into Fastboot/Bootloader mode.

Step 5 – To boot into Fastboot mode: turn on the tablet while pressing and holding the Volume Up and Power buttons until the Fastboot menu and START icon appear on the screen.

Step 6 - Then extract the downloaded file to a desired location on your computer (preferably desktop). Go to the folder volantis-LRX21L and then copy/paste all the files to the Fastboot directory.

Step 7 - Using factory image files in your Fastboot directory, run the following commands depending on the OS installed on computer:

• On Windows: Run the file "flash-all.bat".
• On Mac: Run the file "flash-all.sh" using Terminal.
• On Linux: Run the file "flash-all.sh".

Step 8 –That is all you need to do for flashing the stock factory image on your Nexus 9. Wait for the installation process to complete or follow the on-screen instructions on your tablet if in case you are prompted to unlock the bootloader.

Step 9 - Once the installation completes, your tablet will reboot and it may take about 5 minutes for first boot to complete. So, please do not interrupt the process.

Your Nexus 9 is now running the official Android 5.0 LRX21L Lollipop update via stock factory image from Google. Go to Settings > About tablet to verify the firmware installed.

Rooting Nexus 9 on Android 5.0 LRX21L Lollipop Update

Now that you have successfully installed Android 5.0 Lollipop update on Nexus 9, you can go ahead and root the same using Chainfire's one-click rooting tool, the CF Auto Root, using the guide below (courtesy of The Android Soul):

Note #1: The rooting process has been revamped for all devices running Android 5.0, as you now need to flash a modified kernel image first, before being able to root the device.

Note #2: Unlike earlier instances with SuperSU which involved booting a custom image first to install SuperSU into the system partition and then flash/install a patched boot image to make SuperSU work, we can now use a batchscript that automatically unlocks the bootloader and then installs a modified boot image at the single click of a button.

Downloads Required

Nexus 9 CF Auto Root (11.9 MB)

Steps to Root Nexus 9 Running on Android 5.0 LRX21L Lollipop Update via One-Click CF Auto Root

1. Enable OEM unlock via Settings > Developer options.
2. Boot into bootloader mode via adb or hardware buttons as follows:

Power off the device then hold the Volume Down and Power buttons for a few seconds or execute the command: adb reboot bootloader

1. Connect your Nexus 9 to your computer via USB cable.
2. Unzip or extract the CF-Auto-Root-flounder-volantis-nexus9.zip file to your computer.
3. Run the root-windows.bat file.