[Samsung Galaxy A30s Guides, News, & Discussion] mrdrackers:
Could not find a single post or website that correctly explained how to root my Samsung Galaxy A30S that I bought May 2020.

In the end I got it rooted. Here is what I did (I think have to go from memory, not going to restore my phone and try again, was in Knox jail for a week, so not risking that again).

step 0:

download Samsung kies and install

download and install Frija the Samsung Firmware download tool

download adb platform tools and install. Not strictly necessary I think but can be useful and easy way to boot into bootloader if things go wrong.

step 1:

When your phone is new:

update (or wait that the phone updates) to the latest android version

This may take a while an repeated reboots.

step 2

unlock the bootloader :

1. go to Setting>About>Software>Build Number and Tap on the build number repeatedly so that the Developer mode will turn on.

2. In the developer options, there is an OEM unlock option then enable that option.

Now Enter Download Mode Galaxy A30s:

1 Turn Power off the phone

2 Press and hold Volume Down + Volume Up keys together

3 While pressing these keys connecting the phone to PC with USB Cable Data.

4 Release all keys when Download Mode appears.

follow the instruction (ie keep the volume up button pressed for over 7 seconds)

step 3:

use the Frija tool to download samsung galaxy 30s latest firmware, the same one that is also installed on your phone

Once you’ve downloaded the stock firmware file based on your device model number, you can extract the boot.img.lz4 file to patch it via the Magisk Manager app. You do this as follows:

Step 4

Copy only the boot.img.lz4 file from the extracted AP folder to your device storage.

Install 7-Zip-Zstandard or use a windows lz4 command line tool to unpack boot.img.lz4 to boot.img

Download and install the latest Magisk Manager app and install on your phone.

Transfer the boot.img file to an SD card so Magisk can access it (or connect your phone and use file transfer)

Next, open the Magisk Manager app and select Install and choose to Install it again.

Then tap on “Patch Boot Image File”.

Go to internal storage and select your device boot image that you moved to your phone earlier.

Now, wait for Magisk to start patching the boot image.

Once the boot image has been patched, copy the “patched_boot.img” from the internal storage and put it somewhere on your PC.

Next repack it to boot.img.lz4 using 7z or lz4 and then do it again but now pack it boot.img.lz4.tar so ODIN can write it.

step 4:

Make sure that OEM unlock is still off!

Enter Download Mode Galaxy A30s and go to download mode.

Make sure it says FRP lock and OEM lock are off.

Otherwise the ODIN write will fail and OEM/knox protection will kick in during ODIN write and it will fail.

And then you have to wait a week until OEM unlock option in developers option becomes available again.

download latest ODIN version.

Select in ODIN 'AP' and select boot.img.lz4.tar and then write it.

That should work and reboot your phone.

step 5:

you may have to install magisk on your phone again.

Start magisk and make sure magisk and magisk manager are up to date.

use the menu in the upper left corner, choose modules and install busy box.

Now install terminux on your phone and use the su command to see if you can become root.

If you type 'su' in terminux magisk window should pop up and ask if you want to grant superuser access to terminux.