[ASUS ZenFone 6 (2019) Guides, News, & Discussion] Freak07:
Hey guys and girls,

This is a bit of copy and paste for from my guide for the HTC U12+. I thought it might be helpful to people here too.

If you find mentions of the HTC U12+ please notify me and I will correct them.

I couldn´t find any guide on how to root the Asus Zenfone 6 without twrp yet, so I thought maybe it´s good to have one. It´s also useful for people who don´t like to boot/flash the recovery but want root access.

I also decided now to do a little write up about the A/B slot partition system.

General Information about the A/B slot partition system and seamless updates

Google firstly introduced seamless updates on the Pixel Phones and with it the A/B partition system.

So this means, contrary to non A/B devices, there are two copys of most partitions except userdata.

We have two system (system_a and system_b), two boot (boot_a and boot_b) and two vendor (vendor_a and vendor_b) partitions, amongst others (can be found further down in the partition list but let´s concentrate on these).

When booted in the OS, one slot is actively used and the other is "inactive".

The main advantage that emerges now is, that in case an OTA arrives the "inactive" partitions get updated, while the OS is running. That means while the actual OTA is happening you can use your phone just like you always do.

The following reboot will boot into the former "inactive" slot and use the seamless updated partitions. This happens seamless and just with a reboot. So OTAs are much faster!

If you are interested further here are some links:

https://www.xda-developers.com/list-android-devices-seamless-updates/

https://source.android.com/devices/tech/ota/ab/

https://source.android.com/devices/tech/ota/ab/ab_faqs

Here’s another writeup from the XDA portal!

https://www.xda-developers.com/how-...ess-updates-affect-custom-development-on-xda/

But here are a few tips and tricks:

How to reboot to bootloader to be able to use fastboot:

From booted OS with buttons: Press and hold power down until the screen goes black, then press and hold power and vol up to enter bootloader

non responding and the phone isn´t booting: press and hold power plus volume up to enter bootloader

From the OS or recovery via ADB (requires USB Debugging enabled in dev options):

adb reboot bootloader

How to get the active slot:

fastboot getvar current-slot

How to set the active slot:

A word of advice. If you don´t know what you´re doing you should probably not change slots. Because my U12+ only has a working A Slot. The B slot is without the first OTA or flashing a RUU unbootable.

Set active slot to a:

fastboot --set-active=a

Set active slot to b:

fastboot --set-active=b

How to extract the boot.img from a firmware.zip

1. Download the firmware zip from here : https://www.asus.com/Phone/ZenFone-6-ZS630KL/HelpDesk_Download/

2. Follow the steps described here: https://xdaforums.com/nokia-7-plus/how-to/guide-how-to-extract-payload-bin-ota-t3830962

3. Obtain your boot.img

How to root your phone without TWRP

Prerequisites:

- unlocked bootloader

- USB-Debugging in developer options enabled

- latest adb and fastboot binaries (can always be found here

- working adb and fastboot environment

- magisk-patched boot.img

How to:

1. Download the latest magisk manager from here and install it on your phone: https://github.com/topjohnwu/MagiskManager/releases

2. Get a boot.img that fits your current firmware. Look at the point above, how to extract it from an Asus firmware zip.

Important: if you decide to use a pre-patched boot.img (available below), download it and place it in your fastboot folder, then skip to step 11!

3. Copy the extracted boot.img to your phone

4. Open the magisk manager app and tap two times on install

5. Now choose patch boot.img file and select the previously extracted boot.img you copied to your phone in the upcoming file chooser

6. Wait for the boot.img to be patched

7. Now connect your phone to your pc and make sure usb debugging is enabled in developer options

8. Open up a terminal in your fastboot folder and make sure adb is working by typing

adb devices

into terminal which should return your serial number

9. Pull the patches boot.img to your fastboot folder via:

adb pull /sdcard/Download/magisk_patched.img

10. Reboot to bootloader:

adb reboot bootloader

11. Flash the magisk patched boot.img:

fastboot flash boot magisk_patched.img

12. Congratulations you´re now rooted.

Pre-Magisk-Patched boot.imgs

Important: Make sure to download the correct version, that matches your firmware.

Downloads: https://www.androidfilehost.com/?w=files&flid=295609