[GUIDE] Root NVIDIA SHIELD Experience Upgrade v7.2 with Magisk v18.0

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Aug 31, 2020
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so just to be clear you followed guide at beginning of this thread using latest version of Magisk and the Developer Images and it worked? Thank you!

With a small deviation: E.5 to E.10 I performed on another Android system.
On the Shield I completely installed the developer upgrade 8.2.0 with flash-all.bat, according to NVIDIA instructions, before flashing only magisk-pached(boot).img with fastboot.
And yes, it worked.
 

cHECKjAM

Senior Member
Aug 28, 2015
117
12
that doesnt matter.. both can be rooted

Sent from my SM-G988U using Tapatalk


Hey mate. You seem to know a lot about this.
So if both developer image and stock/recovery image can be rooted, what are really the difference between them? What are the usecases or downsides for the developer version?

I want to go for the developer version just because you can skip google login on this version I have heard, but are there any downsides for me to use the dev version compared to stock/recovery?

Also why do people root in general for the nvidia shield TV?
I have the 2019 PRO model and I would like to root to be able to mass uninstall a lot of the crap that is preinstalled since Im not gonna use any of them. Is this possible without root?

Also I would love to get AFwall or any other firewall running on the shield but I dont think it works. Do you know of any way to get firewall functions in there_?
 

cHECKjAM

Senior Member
Aug 28, 2015
117
12
First page says to not lock bootloader unless default nvidia rom. But what about the official nvidia Dev rom?

The new 2019 pro will not have ai upscaling enabled unless locked bootloader.

Also with Dev room can I just install magisk manager through a normal apk install and have it give root?

Thinking if that would not require special image then and just use latest dev room that has root. Put on magisk and then lock bootloader..?
 
Aug 31, 2020
10
0
First page says to not lock bootloader unless default nvidia rom. But what about the official nvidia Dev rom?

The new 2019 pro will not have ai upscaling enabled unless locked bootloader.

Also with Dev room can I just install magisk manager through a normal apk install and have it give root?

Thinking if that would not require special image then and just use latest dev room that has root. Put on magisk and then lock bootloader..?
Hi there, because you have written to me with a PM, I would like to share a few thoughts on this subject in general. First, I rooted a Shield TV 2017 as described using the developer OS. Unfortunately, I don't know if this approach works with the Shield TV 2019 Pro. Secondly, the APK's installed by me, that require root access, work well on my Shield TV 2017. I guess that would also work on a rooted Shield TV 2019 as well. If you may use the method described here to root your Shield TV 2019 Pro, I'll also consider buying this box to use AI, even if I would have to lock the bootloader afterwards.
 

cHECKjAM

Senior Member
Aug 28, 2015
117
12
Hey Buddy.. nice to see a response!

Mate I have a hard time understanding everything..

1. If using dev image what is the minimum amount of effort needed to run something that requires root, like AFwall? Do you really need twrp and doing stuff through there?

2. Can you lock bootloader if using dev image?
 
Aug 31, 2020
10
0
Hey Buddy.. nice to see a response!

Mate I have a hard time understanding everything..

1. If using dev image what is the minimum amount of effort needed to run something that requires root, like AFwall? Do you really need twrp and doing stuff through there?

2. Can you lock bootloader if using dev image?

1. An installed developer OS should be additionally rooted so that APK's that need root can work well. But I really can't say what stable method is needed to root the Shield TV 2019 Pro.
2. You can lock or unlock the bootloader with developer OS as often as you want. Always when you unlock, you lose all users data.
 

cHECKjAM

Senior Member
Aug 28, 2015
117
12
1. An installed developer OS should be additionally rooted so that APK's that need root can work well. But I really can't say what stable method is needed to root the Shield TV 2019 Pro.
2. You can lock or unlock the bootloader with developer OS as often as you want. Always when you unlock, you lose all users data.

I tried adb install AFwall+ on the developer image but it claims to be missing root.

So I did what you said above and patched the boot.img on another device with magisk 20.4
then in fastboot I did the fastboot flash magisk_boot.img

now stuck in bootloop.. Dunno how to get out of it.. Guess I have to disconnect harddrive and connect the keyboard in there now and boot it up to fastboot that way. Then reflash everything...

Just annoying that I dont seem to understand how to get root on this latest developer image.. And the only active person in the entire community last 10 days has been you.. This place is virtually dead..
 

cHECKjAM

Senior Member
Aug 28, 2015
117
12
Anyone managed to root a 2019 Pro model with 8.2 Dev image yet?
I really want to be able to put magisk on this machine to be able to run apps that require root on it.
 

pinkBEAT

New member
Sep 2, 2020
3
0
Is this still relevant for 8.2.0 Shield version on a 2017 Shield?

Hello, I have a 2017 Shield...16GB. Looking to root it....first time rooting anything. Want to be thoroughly informed b4 proceeding. About 4 months ago I add a 500GB Seagate Fast SSD drive and adopted it as Internal storage because there were a lot more apps I wanted to install and I wanted to get off the adopted thumbdrive. Then I decided I want to use the Plex server on Shield instead of my laptop so I don't have to always have it on. This is the problem I've run into that makes me want to root...If u tell the Plex server to save data to your external HDD it still saves certain data on Shield's internal drive which is eating up my Shield's internal storage quickly. Don't have the option to make it save all data to the adopted storage either and I thing a lot of apps are storing on Shield and not the ssd as well. So what the hell was the use of getting the SSD? Anyway, I've read that if u root it, delete the Plex server and download the Plex server app from the Google store, you can put it on the adopted storage and have its data stored there too as well. This would actually make use of the SSD as I thought it would work in the first place. Now I have to do a dog and pony dance just to have that logical function, otherwise Shield is useless as a Plex server to me. Damn, remote doesn't work half the time either. So, I've decided to try the root route. I'm on the Shield version 8.2.0 and want to make sure this still works, where to get the right updated files for my version and is it going to break any functions or services? Forgive me if I haven't read all 44 pages here. I've read 3 so far. Can't really find any updated info for 2020 regarding the 2017 Shield root. Just really aggravated I have to do this. I mean who thinks up that they will offer a Plex server as a feature, through a 16 GB drive in there, tell u that u can expand storage with an ssd then not let u move all that server data to said adopted ssd or all of it to even an external drive? I've only been able to set my movie library up and now I've only got 2.1GB left on Shield internal. Sorry, went off on a rant.
 

cHECKjAM

Senior Member
Aug 28, 2015
117
12
Hi, I rooted my Shield TV 2017 with Shield Experience 8.2 by flashing a patched boot.img, witch I made on my rooted Phone with MagiskManager v7.5.1.apk and Magisk v20.4. Everything works well!

Hey buddy,

Which TWRP file did you use?

Im planning to flash and root my 2017 Pro 16gb model with 8.2 developer image (developer image because I want to bypass google signin requirement).

I understand most of these steps but I dont know what TWRP we need to use for this process..? First page instructions of this guide does not mention it either.
 
Aug 31, 2020
10
0
Hey buddy,

Which TWRP file did you use?

Im planning to flash and root my 2017 Pro 16gb model with 8.2 developer image (developer image because I want to bypass google signin requirement).

I understand most of these steps but I dont know what TWRP we need to use for this process..? First page instructions of this guide does not mention it either.

Hi there,
I didn't use any TWRP file to flash and root my Shield TV 2017 (not Pro) 16 GB with 8.2 developer image.
 

cHECKjAM

Senior Member
Aug 28, 2015
117
12
Hi there,
I didn't use any TWRP file to flash and root my Shield TV 2017 (not Pro) 16 GB with 8.2 developer image.

Thanks buddy.

I managed to get 8.2 Developer image flashed and rooted with magisk as well, on a Shield Pro 2017 16gb.

However I got a weird problem.. I did the same procedure on 2 devices, the exact same devices.
And none of them can actually connect to a bluetooth device. It never finds any bluetooth device when I search for them.

Does your device find bluetooth devices?

I think maybe the fact that I skipped google login has an effect on this.. In the setup screen I hit the combo Up Up Left Left and hit "skip setup" so I dont need to login with google account.

I need to reflash everything from scratch and try another method by @mrhamed to bypass google setup and see if that works.
 
Aug 31, 2020
10
0
Thanks buddy.

I managed to get 8.2 Developer image flashed and rooted with magisk as well, on a Shield Pro 2017 16gb.

However I got a weird problem.. I did the same procedure on 2 devices, the exact same devices.
And none of them can actually connect to a bluetooth device. It never finds any bluetooth device when I search for them.

Does your device find bluetooth devices?

I think maybe the fact that I skipped google login has an effect on this.. In the setup screen I hit the combo Up Up Left Left and hit "skip setup" so I dont need to login with google account.

I need to reflash everything from scratch and try another method by @mrhamed to bypass google setup and see if that works.

Hi,
My box finds and works well with Bluetooth.
 

Walter Bishop

Member
Nov 25, 2017
42
4
---------- Post added at 08:40 PM ---------- Previous post was at 07:59 PM ----------

Now how do I prevent my shield from ever updating again without my consent? Anything at root level I could do to make sure it can't ever happen?
[/QUOTE]


look if you want the answer ill print it on top here because this is a little long but i encourage you to read on there's some real solid experience and advice in there about this very question. its kina funny too and really sad at the end. But its the truth and you'll get nothing more truthful and straight to the point and entertaining anywhere else on this site. I mean your reading anyway right. that sucks but this will at least answer your question if not stir a little something in you. I hope i don't get dinged for this

delete the tegraota.apk from one of the system folders its like data\app\system or data\syste\app
I also would like clarification on this. because after i plugged my shield in looked at it for a sec went to go get a drink and came back mine updated from like 7.0.1 to like 7.2.0 and a bunch of stuff stopped working no netflix for one and the plex app was different like there was no letters on the side of the library to skip down to the t's some other stuff to so that was my first mission right after rooting and making a backup with tibo. The solution was to rename or delete THE tegraota.APK WHERE ever that is but it's not fool proof like you would think i don't know if i got put on some list with nvidia for the flawed ota or what but if they want to update you your getting it trust me. the I got in a big fight with my girl because i was explaining to her what happened and how they shouldnt have been able to push an update like that because not only did i turn off updates but the system no loger had the tegraota program at least not anywhere it was gonna be able to run. I got to wondering had somebody maybe screwed with it because like all the settings were back where the where initially and like my apps were not where i put them on the desktop . some how she interpreted this as me accusing her of messing with my stuff. I know she didn't do that even accidentally i just trust her implicitly and was running it by her because we've had problems with people breaking into the house to steal information or mess with the cars so we couldnt get to work before and i just asked her like an idiot thinking surely she knows what im talking about. But long story short it took a couple of days before i could find anyone specifically mention the name tegraota and it was obvious to me that the update occured again after i renamed and relocated the apk to a tegraota RENAME TO APK AND PUT BACK IN DATA APP FOLDER.bmp file and put it in my tibo backup folder. I reset every thing the best i could i didn't put all my apps back because for some reason if it didn't naturally show up on the home screen some of the stuff was deleted and any order i put to the feeds and icons on launcher were reset. after i just did it 2 three days ago this time i just deleted it from the sysyem and any other apk that was nvidia or update that i thought might even phone home or i thought the system would be ok without . This time it was on 7.2.2 but after deleting all those apps i had months to get my stystem xposed and spelled with majisik so she wore just what i liked she did all those only a charmer or a rich kid with a trust fund who can pay for it can get a girl to do and just about the time i kept just staring at her and trying to think man what else can she do and all i could think of was nothing shes perfect i think well just watch netflix and eat some pop corn ypu know well that didnt last long soon the externals ive never had problems with every once in a while i had to manually connect the netflix stopped workin ok google would no longer power on or off the machine and apparently it though no streaming apps except you tube were searchable and basically it never did anything else finally the hot word stopped working at all and the kick in the teeth was it updated my gamepad so that it cant charge so it is always plugged it or its in another room becuase it keeps randomly pushing buttona when its critically low and it was making us fight because i kept thinking somebody must be screwing with me because i was the only one that noticed it ever and my girl when she would finally notice it i must be sitting on the remote of course it all made since once we both thought about it. NVidia says update or no controller i mean i just got the damn thing like 3 months ago and the updates never made it better and at the time i was on the last update that could even be downgraded a little bit just enough to get root trust me i was already fuming and completely regtretting my purchase 5 minutes after i plugged it in at that point when the system updated me before i knew what happened to a point were i can no longer 97% of the firmwares the provide for you on thier site i almost lost it i really agonized over the purchase because ive bought cars that cost that much because sometimes we didn't have a car and this is like a major purchase that i can do but not on something i complely not happy with. And I really feel like they ****ed me i spent extra to make sure it was the one with the big hdd the 2015 model so and even got it from nvidia i did lots of homework i knew i would be able flash what ever i want back to like android 3 thats one of the main things i wanted plus upgrade support ive been screwed with that knox bootloader bs from samsung i know how sad i was to read about all those cool like really old chopped up roms people used to make on my phone the caddi one with the gold trip i got with all my christmas money for like 2 years but oh no screw yourself some more so it will technically work so we wont have to fix it for you but it wont be what you signed up for thats what nvidia says no root no use it sits there my useless christmas presents probably the last ill every get from the people i love. despite all that for the most part deleting that file works but there are instances where this fails i can find no evidence of how it occurs the internet as a whole ignores searches on the issue so its obviously supposed to not be known by everyone when google ignores you complety or runs you into a wall everytime you see your terms in a result this must be the case or its really new and no one has figured it out and shared about it yet. i don't remember being on a beta list or sighning up for a hotfix but they say that will force you to update till its over but even that should not happen with the ota.apk deleted but look man theres another nvidia app somewhere in there that can download stuff i promise you any software designer worth half his salt knows how to get into his own work so backup backup backup somewhere else if this is important to you AT LEAST ONE GOOD COPY WITH WHAT YOU KNOW YTOU WANT THIS DEVICE IS NO LONGER DOWNGRADABLE AND SINCE THE STARTED TALKING ABOUT THE NEW ONES IT S ONLY GOTTEN TIGHTER AND NVIDIA STOPPED BEING HELPFUL AND THEY KEEP ACTING DUMBER ON THE ISSUE WHY EVEN KEEP THE FIRMWARE SITE UP ANY MORE THEY PUBLISH A DEV VERSION STILL BUT ITS NOT ROOTED THAT MEANS ITS NOT A DEV VERSION ANY MORE IF YOU WERENT BEING UNDER HANDED AND 2 FACED YOUD CALL IT STOCK VERSION 2 DEVS NEED ROOT HOW STUPID DO YOU THINK WE ARE JUST STOP PISSING FROM THE TOP NVIDIA WE GET IT.
 

ldeveraux

Senior Member
Nov 20, 2008
2,528
915
Lenovo Thinkpad Tablet
Nexus Q
---------- Post added at 08:40 PM ---------- Previous post was at 07:59 PM ----------

Now how do I prevent my shield from ever updating again without my consent? Anything at root level I could do to make sure it can't ever happen?

I don't know what you quoted, but don't do that. You can disable OTA updates in Titanium Backup by searching for "OTA" and "update" and disabling intelligently.
 

Walter Bishop

Member
Nov 25, 2017
42
4
I don't know what you quoted, but don't do that. You can disable OTA updates in Titanium Backup by searching for "OTA" and "update" and disabling intelligently.


like i said tegraota.apk is removed to stop updates. This works 90% of the time and is the only way to keep from updating automatically that i know off. But i still come home some times and The System has been updated . I left that for someone who asked. It was both an answer and a cautionary tale.
 

ldeveraux

Senior Member
Nov 20, 2008
2,528
915
Lenovo Thinkpad Tablet
Nexus Q
like i said tegraota.apk is removed to stop updates. This works 90% of the time and is the only way to keep from updating automatically that i know off. But i still come home some times and The System has been updated . I left that for someone who asked. It was both an answer and a cautionary tale.
I completely misread the forum, thought this was for another device. You can ignore what I said previously, sorry!
 

Ghisy

Senior Member
Mar 27, 2010
1,754
562
I managed to get 8.2 Developer image flashed and rooted with magisk as well, on a Shield Pro 2017 16gb.
Hey, I have the same device and just updated to 8.2.2 Developer image but lost root.

How do I install Magisk 23 on this? Should I patch the boot.img on another device and flashboot flash it to the Shield TV?

I'm also interested in installing TWRP as well (I had it before updating) but I can't find an up-to-date guide anywhere.

Thanks!
 

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    (Note before you begin: If you have a SHIELD TV 2017, you will need a quality Male-to-Male USB Type A cable to connect your SHIELD TV to a PC. If you have a SHIELD TV 2015 or a SHIELD TV Pro, you may be able to just use a regular micro USB cable, because those two models have a micro USB port)

    A. Download these files to your PC:
    1. Download the Android SDK Platform-Tools
    2. Download the Official NVIDIA SHIELD family Windows USB Drivers
    3. Download the Magisk Manager APK (This is the latest version as of the time of writing)
    4. Download the ***CORRECT*** NVIDIA SHIELD Experience Upgrade v7.2 Image for your model
      (You will need to register for a Developer Account if you don't already have one. Flashing the wrong image will BRICK your device)

    B. Setting up Android SDK Platform-Tools on your PC:
    1. On your PC, extract the Android SDK Platform-Tools somewhere where you can find them
    2. Add the platform-tools folder to PATH in the Windows System Environment Variables (Instructions HERE or HERE)

    C. Installing the Official NVIDIA SHIELD family Windows USB Drivers on your PC:
    1. On your SHIELD TV, enable developer options and debugging (Instructions HERE)
    2. Using a Male-to-Male USB Type-A Cable, connect the USB port further away from the HDMI port on your SHIELD TV to your PC
    3. On your PC, extract the Official NVIDIA SHIELD family Windows USB Drivers somewhere where you can find them
    4. Open Device Manager and find the new device
    5. Right-click it and select Update driver
    6. Select "Browse my computer for driver software"
    7. Input the path to the folder where you extracted the Official NVIDIA SHIELD family Windows USB Drivers earlier (make sure the "Include subfolders" option is checked)
    8. Click Next and Install the Driver (if there is more than one option, select the one relating to ADB or Android Device Bridge)
    9. Open a Command Prompt and type:
      Code:
      adb devices
    10. On your SHIELD TV, a prompt will pop up asking you to allow ADB access from your computer. Check the box to remember your selection and then Grant Access
    11. On your PC, the Command Prompt should show the serial number of your SHIELD TV
      (You may have to run the 'adb devices' command again since it may have timed out the first time waiting on you to authorize the ADB connection on the SHIELD TV)
    12. Boot the SHIELD TV into bootloader/fastboot mode by typing the command:
      Code:
      adb reboot bootloader
      (Alternatively, you can enter bootloader/fastboot mode by following the instructions HERE)
    13. On your PC, open the Device Manager again and find the new device (it will probably have an error with a yellow triangle)
    14. Right-click it and select Update driver
    15. Select "Browse my computer for driver software"
    16. Input the path to the folder where you extracted the Official NVIDIA SHIELD family Windows USB Drivers earlier (make sure the "Include subfolders" option is checked)
    17. Click Next and Install the Driver (if there is more than one option, select the one NOT relating to ADB or Android Device Bridge)
    18. Open a Command Prompt and type:
      Code:
      fastboot devices
    19. The Command Prompt should show the serial number of your SHIELD TV

    D. Unlocking the bootloader on your SHIELD TV (CAUTION: THIS WILL WIPE YOUR DATA AND FACTORY RESET YOUR SHIELD TV)
    1. Plug the NVIDIA SHIELD TV Game Controller or a USB Keyboard into the USB port closest to the HDMI port on your SHIELD TV
    2. In bootloader/fastboot mode on your SHIELD TV, select "Unlock Bootloader", read the message and confirm
      (Use the Y and X buttons to scroll UP and DOWN, and the A button to CONFIRM selection, if your button presses aren't doing anything you need to reboot the SHIELD TV into bootloader/fastboot mode with the Controller or Keyboard already plugged in)
    3. On your PC, open a Command Prompt and reboot your SHIELD TV to the OS by typing:
      Code:
      fastboot reboot
    4. This process only needs to be done once per device and you will not have to unlock the bootloader again for subsequent updates
      (From now on while your bootloader is unlocked, your SHIELD TV will display a warning message when it first boots saying that the system cannot check for corruption. This is perfectly normal and the boot process will resume automatically after a few seconds. There is no need to relock your bootloader unless you are selling the device or something. NEVER lock the bootloader if you have anything other than 100% stock full RECOVERY Image installed. Never even try it.)

    E. Installing Magisk Manager on your SHIELD TV and Patching your boot.img
    1. On your PC, extract the NVIDIA SHIELD Experience Upgrade v7.2 Image that you downloaded to somewhere where you can find it
    2. Find the boot.img file in the folder that you extracted it to
    3. Open a Command Prompt and type:
      Code:
      adb push boot.img /storage/emulated/0/Download/
    4. Install Magisk Manager by typing 'adb install [path-to-magiskmanagerapk]' example:
      Code:
      adb install C:\MagiskManager-v6.1.0.apk
    5. On your SHIELD TV, open Magisk Manager [Settings > Device > Apps > Magisk Manager > Open]
      (The Magisk Manager App Interface is not designed to be operated with an Android TV Remote so I suggest you install the NVIDIA SHIELD TV app on your phone. Once paired with your SHIELD TV, the app has an option to let you use a virtual mouse to navigate and interact with your SHIELD TV. Alternatively, you can plug a USB Mouse into the USB port closest to the HDMI port on your SHIELD TV)
    6. If Magisk Manager automatically pops up and asks you if you would like to Install Magisk, select Cancel
    7. Make sure the "Preserve AVB 2.0/dm-verity" option is checked, and then select "Install"
    8. Select "Patch Boot Image File"
    9. Using the Virtual Mouse on the NVIDIA SHIELD TV remote app on your phone, or a USB Mouse, navigate to the "Download" folder on your internal storage and select the boot.img file that you copied over then click Open
    10. Magisk Manager will take a few moments to patch the boot.img (pay attention to the message in the console about the path to the patched_boot.img - It should be "/storage/emulated/0/Download/patched_boot.img"
    11. On your PC, in the Command Prompt type:
      Code:
      adb pull /storage/emulated/0/Download/patched_boot.img

    F. Installing Magisk rooted SHIELD Experience Upgrade v7.2 on your SHIELD TV:
    1. On your PC, navigate to the folder where you extracted the NVIDIA SHIELD Experience Upgrade v7.2 Image
    2. Find the boot.img and rename it to boot.img.bak
    3. Rename the patched_boot.img to boot.img
    4. Open a Command Prompt and type:
      Code:
      adb reboot bootloader
    5. Once the SHIELD TV is in bootloader/fastboot mode, type:
      Code:
      flash-all.bat
      (It will take a few minutes for the flashing process to finish and then the SHIELD TV will automatically reboot to the OS)

    Optional Stuff and Additional Information:
    • Disable Auto-Upgrades by going to [Settings > Device > About > System upgrade > Auto-upgrade]
    • Enable Full OTA's instead of Partial/Differential by going to [Settings > Preferences > Developer options > Provide full system upgrades]
      (It is the very last option at the bottom and this is very important when using a rooted device and modifications to the System partition are likely)
    • If you want to upgrade to a new OTA update with root without waiting on NVIDIA to post the Developer/Recovery images, the downloaded OTA file is in
      Code:
      /data/data/com.nvidia.ota/app_download
      (You will need a root file explorer to be able to access this directory)
    • You can extract the boot.img from the OTA zip and patch it using the same method described in step E.5 through E.10
    • You can then install the OTA the normal way [Settings > Device > About > System upgrade > Check for upgrade]
      (Make sure you have copied the OTA zip or extracted the boot.img to somewhere on your Internal Storage like "/storage/emulated/0/Download" BEFORE you install the OTA because the system will delete the file in "/data/data/com.nvidia.ota/app_download" when it installs the update and you will be unable to get it after that)
    • Copy the patched_boot.img that you made with Magisk to your PC
    • Reboot to bootloader/fastboot mode with:
      Code:
      adb reboot bootloader
    • Manually flash just the Magisk Patched boot:
      Code:
      fastboot flash boot patched_boot.img
    • Manually reboot back to the OS with:
      Code:
      fastboot reboot
    8
    Hi guys, just want to add my 2 cents here...

    I recently bought a Shield TV, witch came with Shield Experience 8.0.0 (android 9 Pie) installed. Well, I can't live without root.
    So, when I realized that, for the moment, we can't root Pie, my option was to downgrade and root Shield Experience 7.2.3.
    First, I have to thank @ACiDxCHRiST for starting this thread and giving us a way to go. And I have to thank @mLgz0rn that gave me the light at the end of the tunnel on post #187 on this thread, when I was about to give up.

    After following @ACiDxCHRiST guide, I ended up, like many others, with a partial root, as I couldn't write to /system dir, and I wanted to get rid of some crappy system useless apps, so my quest continued.
    Digging on this topic, found about my villain, dm-verity, and after a sleepless night, thousands of flashing and bootlooping, and frustrating results, I found post #187 by @mLgz0rn, and started tests using his hint. After a while, and a few more flashes, I finally got my system 100% up and running, with Shield Experience 7.2.3 and full root access! (now I can sleep in peace).

    So, below is my "step-by-step" to accomplish this on my Shield. Just to state, I have a 2017 NVIDIA Shield with 16gb (Darcy), model P2897. This step-by-step starts with Shield TV on Pie, and goes until Oreo full rooted.
    It seems long, but it's really simple, I just detailed some things that gave me headache, so others can archive this more easily.

    Just want to share my results, as I was struggling with this, others might be in the same situation...

    01 - Install NVIDIA drivers on PC
    02 - Enable Developer Options
    03 - Enable USB Debugging
    04 - Connect USB on Shild USB port away from HDMI and on PC
    05 - Download "NVIDIA SHIELD TV 2017 Developer Only OS Image" (https://developer.nvidia.com/gameworksdownload - nv-recovery-image-shield-atv-7.2.3-dev_rooted.zip - 1.167.617 KB)
    06 - Unpack to a folder with ADB access
    07 - Open "Command Prompt" (I use Windows 10, and I'm openning "Command Prompt" with Admin Privileges)
    08 - Go to your ADB folder, where you unpacked nv-recovery-image-shield-atv-7.2.3-dev_rooted.zip
    09 - Run "adb devices" to connect to SHIELD (grant permission on Shield if prompted)
    10 - Plug your Shield Controller on USB port next to HDMI
    11 - Reboot in bootloader (run "adb reboot bootloader")
    12 - "Factory Data Reset" your device (last option on Fastbot Menu, should take a few minutes, won't take long)
    13 - Run "fastboot devices" to check connection to SHIELD
    14 - Install nv-recovery-image-shield-atv-7.2.3-dev_rooted.zip (just run "flash-all.bat"), wait to reboot (always check on install progress to see if your installation finishes OK, after flashing vendor (this is the last file from .bat). Also, when rebooting this first boot on SHIELD 7.2.3 Developer OS, unplug Shield Controller and PC from USB. This will prevent from having issues with WIFI on system first setup)
    15 - Setup your device, and when ready, re-enable Developer Options and USB Debugging
    16 - Go back to "Command Prompt", and again go to your ADB folder, where you unpacked nv-recovery-image-shield-atv-7.2.3-dev_rooted.zip
    17 - Run "adb devices" to connect to SHIELD (grant permission on Shield if prompted)
    18 - Run "adb root" to get Superuser Privileges
    19 - Run "adb disable-verity" to disable AVB 2.0/dm-verity
    20 - Run "adb reboot" for changes to take effect
    21 - On PC, copy Magisk APK to ADB folder (where you unpacked nv-recovery-image-shield-atv-7.2.3-dev_rooted.zip - I'm using MagiskManager-v7.3.2.apk - https://forum.xda-developers.com/apps/magisk/official-magisk-v7-universal-systemless-t3473445)
    22 - Go back to "Command Prompt", and again go to your ADB folder
    23 - Run "adb devices" to connect to SHIELD (grant permission on Shield if prompted)
    24 - Copy your boot image to SHIELD (run "adb push boot.img /storage/emulated/0/Download/") (It's already in this directory (the one from nv-recovery-image-shield-atv-7.2.3-dev_rooted.zip, installed on step 14))
    25 - Install Magisk Manager (Run "adb install MagiskManager-v7.3.2.apk")
    26 - Run "adb reboot" for changes to take effect
    27 - After reboot, open Magisk Manager. You'll need a mouse here, I'm using mouse from Shield TV Remote on my android mobile phone, works perfectly.
    28 - Make sure "Preserve ACB 2.0/dm-verity" is unchecked (it should be already unchecked, mine was)
    29 - Select "INSTALL"
    30 - Select "Select and Patch a File"
    31 - Navigate to your "Download" folder, and select your "boot.img" file (double click on it). Wait for patch to succeed.
    32 - Go back to "Command Prompt", and again go to your ADB folder
    33 - Run "adb devices" to connect to SHIELD (grant permission on Shield if prompted)
    34 - Grab your patched boot image ("magisk_patched.img") from Shield to your PC (Run "adb pull /storage/emulated/0/Download/magisk_patched.img")
    35 - Reboot in bootloader (run "adb reboot bootloader")
    36 - Run "fastboot devices" to check connection to SHIELD
    37 - Install patched boot image (Run "fastboot flash boot magisk_patched.img")
    38 - Reboot your device (Run "fastboot reboot")
    39 - Go back to "Command Prompt", and again go to your ADB folder
    40 - Re-install Magisk Manager (Run "adb install MagiskManager-v7.3.2.apk")
    41 - Reboot your device again (Run "adb reboot")
    42 - After reboot, open Magisk Manager. It will prompt "Requires Additional Setup", click "yes" and system will auto reboot

    That's it, going to Magisk Manager again and you'll see you have it up and running, without "Preserve AVB 2.0/dm-verity" checked.
    First thing I've done after succeeding in this task was to install "3C All-in-One Toolbox" and use it to uninstall "System upgrade" (with a backup, to restore whenever I need, if needed), then I installed AdAway to prevent obtrusive Adds. Also, "Amazon Music" got sentenced to death. Others will follow this way after I get some sleep... :p

    After a sleepless night (lots of hours of trial and error), finally my Shield is working the way I want it to be. That was tricky.

    Hope it helps anyone, just posting it here because it gave me a hard time and I thought others could be in the same situation.
    5
    Oops, I thought I was clearer than this. Yes , I did "fastboot boot twrp-3.3.1-0-shieldtv-pie.img" and it does work. It's using your TWRP that I tried to install magisk. The recovery.txt also came from TWRP.

    Let me know if you have anything else to try.

    Give this zip a try.
    3
    When I type fastboot devices, I get a serial number and the word fastboot

    ---------- Post added at 08:27 PM ---------- Previous post was at 07:53 PM ----------



    So after I go through that process, the shield is "stuck" on, but just showing a black screen. If I reboot it by disconnecting the power, it shows the Nvidia logo for about 20 seconds, then goes to a black screen and I have no way of shutting the shield off except disconnecting the power supply. I remember reading something about starting Win10 with "Disable Driver Signature Enforcement" could help...any thoughts on that?

    Thanks!

    Try and go through the flashing process manually instead of using the .bat.

    Boot into the bootloader.
    Type
    Code:
    fastboot devices
    To make sure that the pc is connected to the shield.
    Should return alot of numbers.

    Make sure your cmd is in the folder where you shield images is locates.

    Then type each of these lines, wait for one to finish continue with the next
    Code:
    fastboot flash staging blob
    fastboot flash boot boot.img
    fastboot flash recovery recovery.img
    fastboot flash system system.img
    fastboot flash vendor vendor.img
    fastboot reboot
    3
    rootfan! You , are a very clever man. Not sure how much effort it was on your part , but thanks to you I now have my Shield 2017 rooted once more! All I had to do was to grab the twrp-3.3.1-0-shieldtv-pie.img from your thread, and the magisk_shieldtv_pie_test.zip that you just posted. I guess it also installs magisk manager ? I already had the latest manager installed , so not sure if it was a pre-requisite.

    Copied magisk_shieldtv_pie_test.zip to root of my Shield
    adb reboot bootloader
    fastboot boot twrp-3.3.1-0-shieldtv-pie.img
    With a mouse :
    Install in TWRP
    select the magisk_shieldtv_pie_test.zip
    Reboot.
    Homepage turned black twice briefly with icons refreshing on screen, then all returned normal.
    Sixaxis controller now works and X-plore shows me the inside of the root folder :D

    From the about menu in my Shield :

    Model Number : P2897
    Version : 9
    Android Security Patch level : July 5 2019
    Kernel Version : 4.9.140-gd1d87e27b7a2-dirty
    #10 Thu Sept 5 16:05:52 MDT 2019
    Build : PPR1.180610.011.4086637_1604.6430
    Shield Android TV SW Version : 8.0.0(32.5.205.42)

    You made me very, very happy. Thank you so much rootfan.

    ---------- Post added at 08:40 PM ---------- Previous post was at 07:59 PM ----------

    Now how do I prevent my shield from ever updating again without my consent? Anything at root level I could do to make sure it can't ever happen?