Please help for a new Mi 9 user.

[Gnahznuy]

Hi, All..
I'm a new Mi 9 user. My device has been unlocked the bootloader.
I hope you guys able to help me out for all of following questions of Mi 9.
1, What's defferent between flash global rom by Miflash and TWRP?
2, What's Vendor.img for? Why most of time need to flash 9.8.1 vendor image before custom ROM and do we need to flash it all of times, when we reflash custom ROM?
3, What's vbmeta.img for?
4, Is it root different ROM needs to flash defferent Magisk version?
I will appreciate for all of you guys answer. Thank you so much.

 

[RebornCheiko]

1.) What's difference between flashing the global rom by Miflash and TWRP?
A: You can flash the stock global ROM using MiFlash, which involves using a PC, in case you brick your phone.
You can also flash a recovery global ROM using TWRP.

2.) What is vendor.img?
A: It contains device-specific hardware drivers, you only need to flash it once. Then you can hop between different custom ROMs.

3.) What is vbmeta.img for?
A: Set of binaries in order for the camera, GPS, bluetooth, WIIF etc to work and communicate to each other properly. I think you don't need to flash this on the Mi 9.

4.) Do some custom ROMs need a specific Magisk version?
A: No, just flash the latest Magisk and it will work.

 

[Gnahznuy]

1.) What's difference between flash global rom by Miflash and TWRP?
A: You can flash the stock global ROM using MiFlash, which involves using a PC, in case you brick your phone.
You can also flash a recovery global ROM using TWRP.

2.) What is vendor.img?
A: It contains device-specific hardware drivers, you only need to flash it once. Then you can hop between different custom ROMs.

3.) What is vbmeta.img for?
A: Set of binaries in order for the camera, GPS, bluetooth, WIIF etc to work and communicate to each other properly. I think you don't need to flash this on the Mi 9.

4.) Do some custom ROMs need a specific Magisk version?
A: No, just flash the latest Magisk and it will work.

So for my understand is the difference between Miflash and TWRP is in case when the phone got brick and able to flash it by PC, am I right? Regrading vbmeta.img. I need to flash it evertime, when I'm flashing pixel experience from global ROM. My steps is from global ROM boot to fastboot mode and "fastboot flash vbmeta vbmeta.img --disable-verity --disable-verification", then flash TWRP and boot to TWRP flash custom ROM. So far, I never flash vendor.img, because of I saw the Pixel Experience ROM had inculd vendor+fw, so I never done in my device.

 

[RebornCheiko]

MiFlash is the "cleanest" way to revert your phone back to stock.
You can only flash global ROM in TWRP when you want to update from 10.0.13.0 to 10.0.14.0 for example. You can't do it when you came from a custom ROM.
You don't have to flash vbmeta.img for the Mi 9 in my experience. I was able to flash Pixel Experience and other custom ROMs without it, but my Redmi Note 7 needs to.

 

[Gnahznuy]

MiFlash is the "cleanest" way to revert your phone back to stock.
You can only flash global ROM in TWRP when you want to update from 10.0.13.0 to 10.0.14.0 for example. You can't do it when you came from a custom ROM.
You don't have to flash vbmeta.img for the Mi 9 in my experience. I was able to flash Pixel Experience and other custom ROMs without it, but my Redmi Note 7 needs to.

I'm not able to use Miflash during the issue length not greater than 0 something like this, so I never use Miflash. Regrading vbmeta.img if I don't flash it before flash TWRP and Pixel Experience ROM, the device not able to boot in to system. I don't know why.

 

[RebornCheiko]

I'm not able to use Miflash during the issue length not greater than 0 something like this, so I never use Miflash. Regrading vbmeta.img if I don't flash it before flash TWRP and Pixel Experience ROM, the device not able to boot in to system. I don't know why.

Use MiFlash Pro v2.

 

[g_seva]

I'm not able to use Miflash during the issue length not greater than 0 something like this, so I never use Miflash. Regrading vbmeta.img if I don't flash it before flash TWRP and Pixel Experience ROM, the device not able to boot in to system. I don't know why.

If the problem is in Miflash, then Miflash is only a GUI for flashing fastboot ROM. You can just run the correct script from folder where you extracted the fastboot ROM tgz. For example for flashing everything without locking recovery: flash_all.bat.

 

[Gnahznuy]

If the problem is in Miflash, then Miflash is only a GUI for flashing fastboot ROM. You can just run the correct script from folder where you extracted the fastboot ROM tgz. For example for flashing everything without locking recovery: flash_all.bat.

Could you instruct how to do it?

 

[g_seva]

Could you instruct how to do it?

1.Download and extract fastboot ROM, it's tgz not zip.
2.Run CMD as Administrator: https://www.howtogeek.com/194041/how-to-open-the-command-prompt-as-administrator-in-windows-8.1/
3.Type: cd C:\here path to the fastboot ROM folder. https://www.techjunkie.com/copy-file-path-windows/
4.Type: fastboot and type adb. (To check if there path is in environment variable)
If they RUN in's fine. If not: https://www.xda-developers.com/adb-fastboot-any-directory-windows-linux/
5.Type: adb devices or check in Mi flash if PC see your device.
6.Type: flash_all.bat or flash_all_lock.bat or flash_all_except_storage.bat (names of the scripts is exactly like options in Mi Flash and do the same)
7.Wait until it's done (don't close the cmd windows if you think it's stuck, you just don't have progress animation in command line)

 

[Gnahznuy]

1.Download and extract fastboot ROM, it's tgz not zip.
2.Run CMD as Administrator: https://www.howtogeek.com/194041/how-to-open-the-command-prompt-as-administrator-in-windows-8.1/
3.Type: cd C:\here path to the fastboot ROM folder. https://www.techjunkie.com/copy-file-path-windows/
4.Type: fastboot and type adb. (To check if there path is in environment variable)
If they RUN in's fine. If not: https://www.xda-developers.com/adb-fastboot-any-directory-windows-linux/
5.Type: adb devices or check in Mi flash if PC see your device.
6.Type: flash_all.bat or flash_all_lock.bat or flash_all_except_storage.bat (names of the scripts is exactly like options in Mi Flash and do the same)
7.Wait until it's done (don't close the cmd windows if you think it's stuck, you just don't have progress animation in command line)

I will try it. Thank you so much for all of information.