OxygenOS Stuck in fastboot during update OOS9 to 19

  1. sksmsn
    Cupcake Apr 1, 2020

    sksmsn , Apr 1, 2020 :
    Was Trying to upgrade from OOS 9 to OOS10 (clean flash like described in https://forum.xda-developers.com/one...lus-6-t3794232). After Flashing OOS10.03, latest TWRP bluespark 9.109, and Magisk 20.4, the phone got stuck after the "bootloader unlocked" startup screen.
    Maybe the problem was I came from 9.08 (seems one first has to go to 9.09 ?), which I learned to late..
    In any case I decided to restore my nandroid backup (OOS 9.08). However, after this I lost the recovery, and now cant flash it back with fastboot. None of the below works:
    fastboot flash recovery TWRPxxx (tells me recovery_a not found)
    fastboot flash boot TWRPxxx (no error, but gets stuck in startup)
    fastboot boot TWRPxxx (no error, but gets stuck in startup )

    I noticed that at startup I see for a moment the Android 10 logo (the little green man), but the OOS I restored with the nandroid backup is 9.08 ! Possibly the phone is now stuck in the Nirwana between Pie and Q ?
    Presumably I have to flash now a ROM and a Recovery via fastbbot, or is there anything else I could try ?
    My questions are now the following:
    - Can I recover using fastboot (bootloader is unlocked) but keep my user data (photo, music etc.) ?
    - If not, is there a way to transfer the nandroid backup from the phone memory to the PC ?
    - If not, which procedure to follow and which files to use.
    I am not sure now which OS I currently have, possibly OOS 9 (as the nandroid restore finished without errors), but then the phone start up with the Anfroid 10 logo before getting stuck..
    Looks I am in a nonstandard situation, so expert help would be much appreciated..

    Title is typo, meant OOS10, not OOS19 (that would be a while in the future :))
    PS: Could I try to swich the active partition ? fastboot getvar all tells me I am in slot a
    bootloader) has-slot:modem:yes
    (bootloader) has-slot:system:yes
    (bootloader) current-slot:a
    (bootloader) has-slot:boot:yes
    (bootloader) slot-retry-count:b:6
    (bootloader) slot-unbootable:b:no
    (bootloader) slot-successful:b:yes
    (bootloader) slot-retry-count:a:7
    (bootloader) slot-unbootable:a:no
    (bootloader) slot-successful:a:no
    (bootloader) slot-count:2
    (bootloader) secure:yes
    Edit: Managed to go back to TWRP recovery by switchng the active partition (fastboot --set-active=b). But what now ? If I would know where to find the nandroip backup, I could possibly save it to the PC with adb pull file, but I do not know where to find it (adb shell ls * list names which I do not know..)
    Last edited: Apr 1, 2020

    H1543401610646 likes this.
  2. Artemus.
    Nougat Apr 2, 2020

    Artemus. , Apr 2, 2020 :
    There's your problem. You have to be on 9.0.9 before you can move to 10.3.x as this build has the necessary files for the transition. You might have a better chance of wiping using the MSM Download Tool and starting over and doing it properly.

    sksmsn, Caomhin and Praty_28 like this.
  3. sksmsn
    Cupcake Apr 2, 2020

    sksmsn , Apr 2, 2020 :
    I now actually managed to boot back to recovery (fastboot boot twrp-3.3.1-18-enchilada-Q-mauronofrio.img). I could save important files back to the PC (via simple drag and drop), including the Nandroid Backup (OOS9.08), music, photos etc..

    In principle I could now try to flash a new ROM.zip, but which one ? Should I go back to the old OOS (9.08), or to 9.09 so I can upgrade to 10 later ? But the TWRP version is Android Q, so maybe I should try 10.0 or 10.3 ?
    Would anybody know which (if any) of these possibilities has the best chance to succeed without wiping the internal data ?
    If a total wipe is unavoidable, what is the best way to proceed ? Is via TWRP recovery possible (clean install, but leave internal data intakt),or do I need fastboot flash which wipes all user data es well (as described https://forum.xda-developers.com/oneplus-6/how-to/rom-stock-fastboot-roms-oneplus-6-t3796665) ?

  4. sksmsn
    Cupcake Apr 3, 2020

    sksmsn , Apr 3, 2020 :
    Problem solved!
    I followed this post https://forum.xda-developers.com/showpost.php?p=78915106&postcount=2
    (reflash same ROM and Magisk versions as those originally installed, then restore nandroid backup).
    3 things to note which were not obvious to me:
    - Unzipp ALL files into one single folder (same ROMs have zips within zips)
    - use the "flash-all-partitions-fastboot.bat" file,
    - answer NO to the first question "Wipe all data (recommended)". If not, the internal data (data/media) will be wiped as well, including your nandroid backup and other info (music, photo..). If you have to wipe, make sure the backup is on the PC

    Artemus. likes this.