yashsingh1/xdaforums huggingface dataset:
[Samsung Galaxy A21s Questions & Answers] SpectreCular:
I have a brand new Galaxy A21 (SM-S215DL). In Developer Options, there is

NO OEM Unlock

toggle (not even a grayed out one; it simply does NOT exist anywhere in settings). I have tried several different variants of the date/time trick to try to get it to appear, and none of them worked. But while in Download Mode, KG Status is shown as `CHECKING`, so doesn't that mean it should at least be visible? Do I even need to unlock my bootloader? Is it even possible?

Using Frija, I managed to get what I believe to be the correct stock firmware for my device. I also grabbed both of the latest official and patched versions of Odin. Flashing the stock firmware works, but flashing the patched Magisk AP fails with an AUTH error for file `vbmeta.img`, which leads me to believe that I actually DO need to unlock my bootloader... but if that's the case, I'm having trouble figuring out how to do so without the OEM toggle.

Is there anything else can I try?
[Samsung Galaxy A21s Questions & Answers] furballi:
I also have the Samsung A21 from T Mobile (SM-A21UZKATMB). The phone is unlocked by T Mobile but there is no OEM bootloader unlock button under the Developer mode. Changing the date (forward and backward in time), then run the software update did not solve the OEM bootloader unlock button problem. I suspect the carrier (T Mobile) has disabled this function. You will need to unlock the bootloader to install the stock firmware.

To those who have enabled the OEM bootloader in the A21. Is your phone locked to a carrier in the USA like Verizon or T Mobile?
[Samsung Galaxy A21s Questions & Answers] namdrop22:
I also have the SM215DL, using straight talk utilizing verizon service, I also cannot unlock the bootloader. Everything you guys did, I did. Nothing worked.
[Samsung Galaxy A21s Questions & Answers] Seriousfreedom:
samsung has done this to all A series phones intended for the U.S. from what i understand
[Samsung Galaxy A21s Questions & Answers] REALSkulldreamz:
Where there's a will, there's a way... someone has messed with my phone too do doesn't that mean that they're altering the data/data partition to r/w. Did you guys try fastboot flashing unlock vs. fastboot oem unlock. I'm going to contact Samsung about this and let u all know what's up.
[Samsung Galaxy A21s Questions & Answers] REALSkulldreamz:
And also why would there be a usb debugging port if this phone can't be modded? Idon't know the answer but maybe someone more expediency could come in and help us out. I also wonder if the flash_image command or just dd it would bypass it?
[Samsung Galaxy A21s Questions & Answers] MaBo2020:
... there is NO way, to root the A21(s), see here: https://xdaforums.com/t/root-possibility.4130739/page-12#post-84944589
[Samsung Galaxy A21s Questions & Answers] thatha:
I confirm that I have rooted my A21S sucessfully using this modified magisk (U3 Rom). No need to patch the whole AP.tar file, just patch boot.img file only. I upload my patched boot.img for those who need it. Just flash it via odin in AP slot. Thank you very much @grccorps.

https://xdaforums.com/attachments/boot-tar.5299081/
[Samsung Galaxy A21s Questions & Answers] MaBo2020:
... exactly Step-by-Step, how u do it with downloadlinks of all Software, what u used !

Many Peoples writes, that they have rooted the A21s, but no one shows, how ! With the newest Firmware u cant rooted the Phone, because there is no working TWRP, SuperSU or MAGISK - Version out for this Phone !
[Samsung Galaxy A21s Questions & Answers] thatha:
Extract boot.img from AP.tar, then use modified-magisk to patched it
[Samsung Galaxy A21s Questions & Answers] MaBo2020:
... this Methode is not working, i try it many Times, no RootAcess ! Again: if u have newer Firmware on this Phone (End 2020 - until now) u cant root this Phone ! Maybe on ure Phone an older Firmware ...
[Samsung Galaxy A21s Questions & Answers] thatha:
And this is my U5 patched boot.img

I have just made a post here, you can try it

https://xdaforums.com/t/sharing-how-to-root-a21s-stock-rom-with-magisk.4272095/
[Samsung Galaxy A21s Questions & Answers] MaBo2020:
... and u shure, it its for the A21s or for A21 ? ;)
[Samsung Galaxy A21s Questions & Answers] mobile_sensei:
The only hope of getting root on this phone is if you find a Dev who's interested enough to build a bootstrap recovery. I've not looked at the firmware & have no idea if there's an exploit that would work for that purpose.

Bootstrap recovery was the only way of getting root/custom recovery back in the days of Motorola D2 & Droid X, the original Droid X. Motorola was THE phone for development... Liberty ROM, Gummy ROM, Simply Stunning, etc.

I would not hold out hopes for that to happen here.

Peace - MS
[Samsung Galaxy A21s Questions & Answers] iBowToAndroid:
No, Samsung has done this to ALL North American models ever since the Galaxy S8. The bootloaders are not user-unlockable, like they are on international models. However, some models can be rooted via a software exploit if they're running very old firmware, or some models can even be bootloader unlocked via special files, if their firmware version is old enough
[Samsung Galaxy A21s Questions & Answers] o.class.jav:
Mine is rooted. But you have to buy a token.
[Samsung Galaxy A21s Questions & Answers] evan.gibson.66@gmail.com:
what token??
[Samsung Galaxy A21s Questions & Answers] o.class.jav:
The one generated by the SamPwns steady.bin flash.
[Samsung Galaxy A21s Questions & Answers] evan.gibson.66@gmail.com:
{Mod edit: Quoted post removed}

and where does one get 'TWRP' for the Samsung Galaxy A21S?? Thanks for the post its very detailed with very clear instructions, and i agree with you this is the tried and tested and perfect way of rooting your phone, only problem is that this is an unperect world a world where 'TWRP' for the SM-A217F does not exist
[Samsung Galaxy A21s Questions & Answers] Nazo:
I just received a refurbished SM-S215DL (A21,) not as my provider's solution to the VoLTE soon to be required for 4G devices thing and right now it's a pretty severe downgrade for me since it lacks a lot of basic functionality I'm used to from my 2017 phone running LineageOS. Obviously it's pretty unlikely or probably outright impossible to ever see a real LineageOS ROM for this thing (and even if someone ever does it probably would be insanely unstable or incomplete,) but if I could at least root it (even if I have to manually patch or something) it would really help me out a lot. Has just nothing really been found short of sending some unknown person online some very very key device details and money (which I don't have or I'd be buying something else anyway)? (Also kind of suspicious that whatever method they're using isn't something available to the public anyway...)
[Samsung Galaxy A21s Questions & Answers] iBowToAndroid:
S215DL can be bootloader unlocked (and therefore rooted) if it's bootloader level 1 or 2
[Samsung Galaxy A21s Questions & Answers] Nazo:
I'm not really sure what that means. All I can say is there is no bootloader unlock option in the developer settings (no surprise there I guess) and fastboot oem unlock is not accepted as a valid command.
[Samsung Galaxy A21s Questions & Answers] iBowToAndroid:
1. No, USA models don't have the OEM unlock option

2. "fastboot oem unlock" isn't a valid command on any Samsung devices because they don't have fastboot mode

3. Your bootloader version is the 5th character from the end, in either the Baseband Version or Build Number. So for example, S215DLUDU2BUJ3 would be bootloader level 2
[Samsung Galaxy A21s Questions & Answers] Nazo:
Right, I get that. I was just verifying it's definitely not there.

Well, up+power gives me a recovery menu and on this one I have an option to go to fastboot mode where it actually does respond to fastboot and says "Entering fastboot mode..." on the screen. Though I don't know anything I can do to specifically verify most of its functionality so the only command I can really use to verify it's working otherwise is fastboot reboot bootloader to get back out of it.

Mine is a 5. Is it possible to downgrade the bootloader with a firmware flash or something or does it lock it down? Presuming so, if I did downgrade, will I be stuck with a seriously outdated firmware or would it be possible to flash updates with everything but the bootloader later if that is the case? (I'm guessing a properly patched bootloader would stop checking, so presumably wouldn't care, but want to double check.)

EDIT: Oops, it was a 5, not a 4. Anyway, I couldn't get a clearer picture due to lighting/etc, but here's what that looks like. Looks like I may be getting this because someone screwed up given that it says "E:Failed to load bitmap installing_text for locale en-US (error -1)" on there and maybe I shouldn't be able to get this screen.

If the answer is yes it can be done, would you be willing to provide details on what do to? I'm used to more generic stuff where you just fastboot flash twrp and go from there rather than Samsung proprietary stuff.
[Samsung Galaxy A21s Questions & Answers] iBowToAndroid:
No, bootloader level can never be downgraded. If there was a way to do that, then I wouldn't specifically say that it has to be bootloader 1 or 2 in order to be unlocked
[Samsung Galaxy A21s Questions & Answers] sabiosho:
Ok I need a new rom on this phone but cant even get OEM Toggle switch to start the process and get boot loader unlocked. Or is thier another way to set up a custom rom on this phone and root it easily?

According to this guide Im running a version 7 of bootloader on this phone currently.

Any Suggestion Anyone?

Thank you
[Samsung Galaxy A21s Questions & Answers] iBowToAndroid:
Nope. Re-read the thread
[Samsung Galaxy A21s Questions & Answers] sabiosho:
Question if you unlock the phone will that open it up to get the bootloader unlocked?
[Samsung Galaxy A21s Questions & Answers] iBowToAndroid:
The word "unlock" by itself is an extremely vague term, since there are so many different types of locks and unlocks, when it comes to mobile devices
[Samsung Galaxy A21s Questions & Answers] rbudrick:
Hello frenns. I'm just a dog on the innerwebs, so please forgive, as I couldn't find a recent definitive answer to: Is there still no way to root an sm-a215u? Seems different a21 models have different answers to this, but a215u is not specified. Thanks!
[Samsung Galaxy A21s Questions & Answers] Nazo:
As far as I'm aware, basically absolutely none can be unlocked unless the ROM offers the option to unlock itself or if you have the older bootloader (unlikely if it has been running.)

Mobile devices? Yes. Android phones? No. This isn't a generic unknown mobile device. It's an Android phone. Unlock has one very specific meaning: unlock the bootloader so custom things can be loaded during boot time (eg Magisk in most cases.)
[Samsung Galaxy A21s Questions & Answers] iBowToAndroid:
- bootloader unlock

- Google account (FRP) unlock

- Rent-A-Center unlock

- MDM unlock

- Samsung KG unlock

- screen PIN unlock

- SIM/network unlock

- rooting (some people refer to this as an "unlock")

- IMEI repair (some people refer to this as an "unlock")

I can keep going....
[Samsung Galaxy A21s Questions & Answers] Nazo:
You know that you're just nitpicking and that 99% of the time people mean the bootloader, but let's put that aside for a second. The title of this thread is "Unlocking/rooting an A21?" and you've obviously read at least one or two posts discussing what this thread is about because you've already participated directly in its discussion of the bootloader in here, therefore you are fully aware what this thread is about. You can't pretend you suddenly don't know what they mean on page two of a thread you've already been participating in since page one.

Now let's please just move on to discussing this phone and any possibilities that might ever arise. For example, it seems to me like the recent Samsung modem exploits might potentially be a root vector. (Well, it's not clear just how elevated the access is, but it sounds pretty major from what little articles say it sounded really huge.) For that matter, it's still unclear if it would even have a Samsung modem. It's not an Exynos SoC, but I suppose Samsung could still put their own modem in with a Mediatek SoC? All the articles list the A21, but I'm not really sure if they might just not properly recognize that the A21 and A21s are completely unrelated hardware despite having almost the same name. It wouldn't be bootloader access, but root access might have its uses. Though an unpatched security issue is a serious issue on its own (I also wonder if said elevated access could be used to do anything like disabling VoLTE or something.)
[Samsung Galaxy A21s Questions & Answers] iBowToAndroid:
I work in the mobile field. When my customers contact me asking for an "unlock", they can mean any of the unlocks that I listed above. That's how my brain approaches it

And since this person asked first about "unlock", and then asked if that would open it up to get the bootloader unlocked, then obviously the first "unlock" means something else.

🤷🏻‍♂️
[Samsung Galaxy A21s Questions & Answers] Nazo:
Ok, don't acknowledge the subject of the thread you're currently posting in, but at least please don't bog it down and let's maybe try to get back on topic please and thanks.
[Samsung Galaxy A21s Questions & Answers] cgwatson1979:
The title for this thread is Unlocking/Rooting and the Unlocking part is agreably ambiguous. Because other people in this thread only want to discus one particular use of the word unlock, can we create a thread specifically to discuss the plethora of its meanings? This seams like an important discussion that I would like to know more about reguarless of where it happens. If the powers that be would like to rename the thread to specify Bootloader unlock it may be apprieciated by people looking for different conversations. Thank you
[Samsung Galaxy A21s Questions & Answers] cgwprs:
I don't understand carrier unlocking being tricky or illegal? The phone I bought was sold as carrier unlocked. Changing carriers is what I am trying to do and for some reason I am not able to set the APN settings to the new carrier. The previous carrier has insisted that the phone is carrier unlocked and the new carrier only says that I must leave cell data on all the time and will not address my APN questions. Another phone that I have has the APN settings fully able to change. I would think that this issue is not a bootloader unlock but a carrier unlock issue. When I own a device it should be legal for me to change the settings. Is this a matter of needing an international version or straight out rooting?
[Samsung Galaxy A21s Questions & Answers] Nazo:
You're trying a bit too hard on semantics there to the point of being contradictory to yourself even. If a phone is actually carrier unlocked then you can't carrier unlock it. You can't unlock a padlock that is sitting there unlocked already. (Especially since this proverbial padlock doesn't generally even have an option to close again.) If it IS carrier unlocked (which you try to imply it is not) then it may be illegal to bypass that because it's essentially circumventing protections and that is why it may be illegal obviously (seems pretty clear from the context-- oh, nevermind.) If a seller sold you a supposedly carrier unlocked phone and it isn't carrier unlocked your real beef is with the seller and you should just return it for a replacement/refund. If not, it's still not a device-specific issue, but more a procedural issue and that's what you should ask in a more appropriate thread. (As for APN settings and such, that too is not device specific. You'd look up APN settings for your new carrier, not your specific phone.) It just makes no sense to look to a thread about a specific device model or to clutter it up with useless discussion of semantics.

Now. This thread is about BOOTLOADER UNLOCKING the A21. Let's please talk about that and stop arguing silly semantics of the word unlock, because at this point we all know that is what this thread is about and there is no longer room for doubt. LET'S PLEASE TRY TO STICK TO THE ACTUAL TOPIC OF THE THREAD PEOPLE.
[Samsung Galaxy A21s Questions & Answers] iBowToAndroid:
Neither. It's a matter of the APN not being editable on that specific software and CSC. You could try a 3rd party app from the Play Store, to see if it gives you access to add an APN
[Samsung Galaxy A21s Questions & Answers] cgwatson1979:
I have tryed using one of those apps and it just didn't work. Some of them looks like scams and I just don't trust them. If there were one on G-Droid/F-Droid, I would be more quick to just try it. Seams like this should be a class action against Samsung. When I bought the phone I was able to edit APN and now I can't. When I used to travel to different countries I changed APN settings often. Thank you for trying to help. If I find a solution I will post it.
[Samsung Galaxy A21s Questions & Answers] iBowToAndroid:
If the CSC is currently set to TFV, changing it may solve the problem
[Samsung Galaxy A21s Questions & Answers] Wish39:
Found this out by chance through playing around with my Tracfone Samsungs, but if you change the phone's CSC to GCF (seems to be a CSC specifically for certification purposes), then the APN menu will allow you to edit and add APN's. You can use the SamFW tool to change the CSC, it's a pretty nice free tool. Just go to Samsung > ADB > Change CSC, select GCF and follow what it wants you to do.

Also before you change it, use ADB to disable this app: "com.samsung.android.cidmanager". It's responsible for changing CSC's depending on what sim you install into the phone (in our case, whether you insert a Tracfone sim or a non-Tracfone sim). If you don't disable it, the phone will just switch right back to TFN (non-TF sim) or TFV (TF sim) if a sim card is inside.

You also won't lose VoLTE, VoWifi etc. Tested this on a Tracfone A32 5G and A21 with a Visible sim card. Be aware though that you won't get OTA updates while on this CSC.

One little quirk is that the LTE icon will now show as 4G or 4G+ just like non US Samsungs lol.
[Touch Diamond, MDA Compact IV General] nosgop:
I haven't found any answers so I've decided to "ask the audience".

To my understanding the Rogers Canada network uses 850/1900 for it's 3G primarily 850. Is this true?

I haven't found a mention of a North American release date for the GSM Diamond. Anyone know the date? I don't expect it till around Christmas.

I'm looking at an Australian Diamond that uses the 850/2100 bands for 3G. Will the support of the 850 band be enough to function on the Rogers network or does the phone have to support both bands for 3G to function on the network?
[Touch Diamond, MDA Compact IV General] Blazeitup123:
only gsm 850 works on my diamond. i think its 1900 for 3g
[Touch Diamond, MDA Compact IV General] nosgop:
I have an European Diamond which works on the rogers network but I get GSM/EDGE but to my horror no 3G :(

Looking around only on a few sites can I find any mention of what works and what doesn't the closest information I could find is from this link:

http://forums.whirlpool.net.au/forum-replies-archive.cfm/843038.html

But someone also says

and they go back and forth so I'm not sure what to believe and I don't think I want to buy another Diamond just to find it won't work either.

http://www.geekzone.co.nz/Jama/585 has some interesting comments as well but I'm not sure what to believe.

Can anyone confirm or deny and of this?

The question is will a Australian phone with the 850/2100 3G radio function on the Roger network?
[Touch Diamond, MDA Compact IV General] Lord_BlackAdder:
I have the Australian version (850/2100 MHz) and it supports the Telstra 3G Network. Can't see why it wouldn't work on other 850/2100 MHz 3G network.
[Touch Diamond, MDA Compact IV General] nosgop:
To my understanding the Canadian Rogers network is a 850/1900 network.

Does the phone need to support both bands or will one suffice?
[Touch Diamond, MDA Compact IV General] raidendb:
Rogers Diamond

I had an EU/Asia Diam and I never manage to get 3G connection. Sold the phone and bought a Rogers branded diam and by default I see 3G connection all the time on the top network status. But now I'm thinking of going back to an EU/Asia version unless I can flash my Rogers branded diam with a better ROM.
[Redmi Note 8 Pro Questions & Answers] Thephoenix0900:
im having a random issue in my device in which when i connect to my wifi i get network speed then somehow after around 10 second or so the speed drops so slow that i cant even send a whatsapp message even youtube streaming or any other thing that requires net doesnt work i have dual band wifi so if i switch to my other wifi then its the same case so basically when ever i need to do something or send a message i need to switch wifi so the messages get delivered and then to recheck if there are any notification or any message i just have to again reconnect wifi plz give a solution either this is a software issue or a hardware issue
[Redmi Note 8 Pro Questions & Answers] AlphaBravo:
My Redmi Note 8 Pro WiFi also keeps on disconnecting. Running on Stock MIUI 12.0.5, Non rooted device.
[Redmi Note 8 Pro Questions & Answers] Sonaalbatra:
Redmi NOTE 11T 5G & Note 7 Pro plagued with Ping spikes during gaming on both Mobile Data and Wifi. PLEASE HELP. Other devices have nice ping on same wifi at same time. 😭😭😭
[Redmi Note 8 Pro Questions & Answers] MysticNoOb:
These lag spikes might be from performance, is your phone overheating?
[Google Pixel 3a Questions & Answers] pojr:
Owned a OnePlus X - I rooted that phone because the manufacturer stopped making updates for it.

Owned a Pixel 1 - I rooted that one, and a while it was nice, it was annoying having to manually update once a month.

Does anyone else think it's not worth rooting just because it's of how much support Google already gives on its lineup of phones? I also checked the ROMs section of XDA, and there doesn't appear to be very many ROMs for this device anyway.

What do you guys think? I'm a big advocate for rooting, but only when the good outweighs the bad. Right? What do you personally use root access for?
[Google Pixel 3a Questions & Answers] ttocs99:
You don't need to root to have a custom rom running. You just need a unlock bootloader and TWRP to flash roms, root is optional.
[Google Pixel 3a Questions & Answers] pojr:
This is true, but you still don't get OTA updates. Doesn't change anything I wrote above. But what you said is accurate, and I'm glad you pointed it out. Because some people may not know the difference between rooting and simply unlocking your bootloader.
[Google Pixel 3a Questions & Answers] Uzephi:
I use J4N's Pixel edge mod. Now when I squeeze my phone, the flashlight comes on instead of the default action. I also use smali patcher to keep my location private to all apps. Don't need permanent root, but I use ElementalX app and flash the kernel Flar2 makes for our device also.

Due to rooting, I don't take updates immediately. I usually take them when big changes or fixes are done, like the recent updates to Vulkan on our phone.

For example, I ran Sept update until mid Dec when I flashed Dec update and the recent ElementalX 3.11 kernel. (Sept was A11 launch and either Nov or Dec had some Vulkan API updates)
[Google Pixel 3a Questions & Answers] pojr:
This is actually really good to know. Seems like a lot of the OT updates that Google pushes out are just simple security or patches.

Question about ElementalX. I installed a custom kernel on an older phone of mine, a lot of people raved about how great it was. From my experiences, however, it seemed like just a placebo effect. Do you actually notice anything with ElementalX? Hope that doesn't come off rude or anything.