[GUIDE]Porting TWRP without source

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Augustoandro

Senior Member
Jun 20, 2017
569
266
Pune
Micromax IN Note 1
Yes, I know XDA is filled with such guides.
But you can only port a TWRP if you implement parts of all the guides.
This guide is a summation of all those guides.

NOTE:
I would be using AIK-Linux in this tutorial, since I don't recommend Windows for all this, who knows what problems you will get into.

REQUIREMENTS:
1.Download these TWRP recoveries in accordance with your screen resolution.
A. If your screen resolution is 480x850, 480x854; download
https://twrp.me/lg/lgnexus4.html
B. If your screen resolution is 720x1280, 800x1280 or 720xsomething; download
https://twrp.me/asus/asusnexus720123g.html
C. If your screen resolution is 1080x1920, download
https://twrp.me/motorola/motorolanexus6.html
2. Download Android Image Kitchen-Linux from this thread:
https://xdaforums.com/showthread.php?t=2073775

LET'S BEGIN:
1. Unzip Android Image Kitchen zip file.
3. Now, navigate to the unzipped folder of AIK (Android Image Kitchen).
4. Just Right Click and select "Open Terminal here".
5. Copy and paste your stock recovery.img and paste it in AIK folder.
6. In the terminal, type the command
Code:
su
Enter your root password, then type
Code:
./unpackimg.sh
7. This will unpack your stock recovery.img. Do not close the terminal.
8. Cut the new folders, ramdisk and split_img, and paste them somewhere outside of AIK folder.
9. Remove the stock recovery.img in AIK folder.
10. Now, copy and paste the twrp_recovery.img according to your screen resolution in the AIK folder.
11. Now, revert back to the terminal and type
Code:
./unpackimg.sh
12. This will unpack your twrp_recovery.img
13. Delete all the files in the new split_img folder we got by unpackimg twrp_recovery.img
14. Copy and paste all the files in stock split_img folder to the new split_img folder.
15. Delete following files from new ramdisk folder.
A. default.prop
B. fstab.devicename_or_chipsetname
C. ueventd.rc
D. Any other file like ueventd.devicename.rc
16. Copy and paste these files from stock ramdisk folder to new ramdisk folder.
Code:
default.prop
fstab.devicename
ueventd.rc
17. Now go into stock ramdisk/etc folder and copy recovery.fstab
18. Paste the recovery.fstab file in new ramdisk/etc folder.
19. Edit the twrp.fstab file according to the newly pasted recovery.fstab
20. You will have to replace"/sdcard" with "/external_sd" and "/usb" with "/usb-otg".
21. If the partitions stated above are not available in your fstab files then add these lines. Order may change on the format in which the files are written.
Code:
/external_sd          vfat         /dev/block/mmcblk1p1  flags=removable;storage;display="SDCARD"
/usb-otg                auto         /dev/block/sda1    flags=removable;storage;display="USB-OTG"
22. Edit the following lines as shown in default.prop
Code:
ro.secure=0
ro.adb.secure=0
security.perf_harden=0
ro.debuggable=1
persist.sys.usb.config=adb,mtp
23. Now, come out of the ramdisk folder and open the terminal.
24. Type
Code:
./repackimg.sh
25. Your new TWRP img would be generated and named as image-new.img by default. You may change the name later.

When you have successfully built the TWRP, or if you want to request one instead of creating yourself, contact me on this thread:
https://xdaforums.com/android/general/unofficial-twrps-devices-source-code-t3833338


SPECIAL INSTRUCTIONS FOR MEDIATEK DEVICES:
1. The recovery.fstab you will get after unpacking your stock recovery.img would be flawed in most cases. I believe OEMs do this deliberately.
2. In order to know which partition is mounted at which location and at which device, you'll need DiskInfo (Install it from Play Store) and a root explorer.
3. Enable the following Diskinfo settings:
Code:
Show mount path
Show partition name
Show file system
Expert mode
Unmounted partitions
Device Mapper partitions
Temporary filesystems

4. Use the root explorer to find the path of your partitions. They would be located under /dev (mtk devices have bootimg and recovery here generally) and some other partitions like /system, /cache would be deeper inside.
5. You can trace their exact locations by navigating within the /dev directory for partition names like mmcblk0p5.


SPECIAL INSTRUCTIONS FOR DEVICES THAT DON'T HAVE RECOVERY.FSTAB WITHIN STOCK RECOVERY.IMG
1. In the ramdisk/etc folder, there might be a dummy recovery.fstab file with the symbol of link on it.
2. Right click on the file and select "Show Target". You'll get to know the path of original recovery.fstab file. It might be within the unpacked recovery or inside some other partition on your phone.
For example: Honor 7C devices have their recovery.fstab in /vendor/etc folder.

TROUBLESHOOTING INSTRUCTIONS:
1. If you get a dm-verity error or facing an encryption problem, go to this thread and flash the "dm-verity and forceencrypt disabler zip".
https://xdaforums.com/android/software/universal-dm-verity-forceencrypt-t3817389
2. If you encounter a bootloop while booting into your new TWRP, please consult post #20 of this thread.
3. At times, the path of partitions during recovery boot is not the same as those during normal boot. That's why you may get errors like
Code:
Updating partitions details...
Failed to mount '/cache' (Invalid argument)
Failed to mount '/system' (Invalid argument)
Failed to mount '/data' (Invalid argument)
Failed to mount '/metadata' (Invalid argument)
...done
Unable to mount storage
Failed to mount '/data' (Invalid argument)
To resolve this, in your TWRP terminal type the following command
Code:
find /dev/block -name by-name
Replace the paths of the partitions in your fstab files with the ones you get as output using the command above (only the partitions which failed to mount).

If there are some bugs or you need some assistance in porting TWRP, contact me by mentioning in your post, for example @Augustoandro, we'll work on it to make it bug-free.

Special thanks to @aIecxs for his troubleshooting instructions of bootloop, "Failed to mount /partition_name (invalid argument)" error and also @inguna for guiding me on how to fix the "SDCARD not detected by the TWRP" problem and also fixing the MTP, ADB not working issue.
Another thanks to @seanybiker and @avirus for their troubleshooting instructions on "DM-Verity and forceencrypt" errors.

CREDITS:
@HostZero for his porting guide.
@osm0sis for his awesome Android Image Kitchen
@Zackptg5 for his "DM-Verity and Forceencrypt disabler zip".
 
Last edited:

SachinBorkar

Senior Member
May 15, 2018
131
16
India
Yes, I know XDA is filled with such guides.
But you can only port a TWRP if you implement parts of all the guides.
This guide is a summation of all those guides.

NOTE:
I would be using AIK-Linux in this tutorial, since I don't recommend Windows for all this, who knows what problems you will get into.

REQUIREMENTS:
1.Download these TWRP recoveries in accordance with your screen resolution.
A. If your screen resolution is 480x850, 480x854; download
https://twrp.me/devices/lgnexus4.html
B. If your screen resolution is 720x1280, 800x1280 or 720xsomething; download
https://twrp.me/devices/asusnexus720123g.html
C. If your screen resolution is 1080x1920, download
https://twrp.me/devices/motorolanexus6.html
2. Download Android Image Kitchen-Linux from this thread:
https://xdaforums.com/showthread.php?t=2073775

LET'S BEGIN:
1. Unzip Android Image Kitchen zip file.
3. Now, navigate to the unzipped folder of AIK (Android Image Kitchen).
4. Just Right Click and select "Open Terminal here".
5. Copy and paste your stock recovery.img and paste it in AIK folder.
6. In the terminal, type
Code:
./unpackimg.sh
7. This will unpack your stock recovery.img. Do not close the terminal.
8. Cut the new folders, ramdisk and split_img, and paste them somewhere outside of AIK folder.
9. Remove the stock recovery.img in AIK folder.
10. Now, copy and paste the twrp_recovery.img according to your screen resolution in the AIK folder.
11. Now, revert back to the terminal and type
Code:
./unpackimg.sh
12. This will unpack your twrp_recovery.img
13. Delete all the files in the new split_img folder we got by unpackimg twrp_recovery.img
14. Copy and paste all the files in stock split_img folder to the new split_img folder.
15. Delete following files from new ramdisk folder.
A. default.prop
B. fstab.devicename_or_chipsetname
C. ueventd.rc
D. Any other file like ueventd.devicename.rc
16. Copy and paste these files from stock ramdisk folder to new ramdisk folder.
A. default.prop
B. fstab.devicename
C. ueventd.rc
17. Now go into stock ramdisk/etc folder and copy recovery.fstab
18. Paste the recovery.fstab file in new ramdisk/etc folder.
19. Edit the twrp.fstab file according to the newly pasted recovery.fstab
20. You will have to replace"/sdcard" with "/external_sd" and "/usb" with "/usb-otg".
21. If the partitions stated above are not available in your fstab files then add these lines. Order may change on the format in which the files are written.
Code:
/external_sd          vfat         /dev/block/mmcblk1p1  flags=removable;storage;display="SDCARD"
/usb-otg                auto         /dev/block/sda1    flags=removable;storage;display="USB-OTG"
22. Edit the following lines as shown in default.prop
Code:
ro.secure=0
ro.adb.secure=0
security.perf_harden=0
ro.debuggable=1
persist.sys.usb.config=adb,mtp
23. Now, come out of the ramdisk folder and open the terminal.
24. Type
Code:
./repackimg.sh
25. Your new TWRP img would be generated and named as image-new.img by default. You may change the name later.

When you have successfully built the TWRP, contact me on this thread:
https://xdaforums.com/android/general/unofficial-twrps-devices-source-code-t3833338


SPECIAL INSTRUCTIONS FOR MEDIATEK DEVICES:
1. The recovery.fstab you will get after unpacking your stock recovery.img would be flawed in most cases. I believe OEMs do this deliberately.
2. In order to know which partition is mounted at which location and at which device, you'll need DiskInfo (Install it from Play Store) and a root explorer.
3. Change the Diskinfo settings like this
https://mega.nz/#!fbIR0AoD!ykRMTAitymE4bQMVc6S0qbCYztTkVZDZSgIKcVTxEHg
https://mega.nz/#!yXQzwKJK!rWO_LiKZwFjzw4ZyM0qzzKw6uopxrxAkSkKNRYXVuIY
4. Use the root explorer to find the path of your partitions. They would be located under /dev (mtk devices have bootimg and recovery here generally) and some other partitions like /system, /cache would be deeper inside.
5. You can trace their exact locations by navigating within the /dev directory for partition names like mmcblk0p5.


SPECIAL INSTRUCTIONS FOR DEVICES THAT DON'T HAVE RECOVERY.FSTAB WITHIN STOCK RECOVERY.IMG
1. In the ramdisk/etc folder, there might be a dummy recovery.fstab file with the symbol of link on it.
2. Right click on the file and select "Show Target". You'll get to know the path of original recovery.fstab file. It might be within the unpacked recovery or inside some other partition on your phone.
For example: Honor 7C devices have their recovery.fstab in /vendor/etc folder.



If it works perfectly, I will make it available to others through my thread.
If there are some bugs or you need some assistance in porting TWRP, contact me all the same, we'll work on it to make it bug-free.

CREDITS:
HostZero for his porting guide.
Osm0sis for his awesome Android Image Kitchen
I tried all these type op method but didnt work on my android.
Please help.
It alway on bootloop and restart normaly

Sent from my Titanium Vista 4G using Tapatalk
 

Augustoandro

Senior Member
Jun 20, 2017
569
266
Pune
Micromax IN Note 1
I tried all these type op method but didnt work on my android.
Please help.
It alway on bootloop and restart normaly
Tell me what happened in detail.
Which files you transferred?
Did terminal show you any errors upon running the commands?
It would be better if you did everything using root account.
Btw, you should give executing permissions to all files inside AIK-Linux/bin
 
Last edited:

SachinBorkar

Senior Member
May 15, 2018
131
16
India
No error occurs during packing and unpacking but.
After flash recovery.img phones stuck on bootloop.

Sent from my Titanium Vista 4G using Tapatalk

---------- Post added at 02:59 PM ---------- Previous post was at 02:44 PM ----------

Tell me what happened in detail.
Which files you transferred?
Did terminal show you any errors upon running the commands?
It would be better if you did everything using root account.
Btw, you should give executing permissions to all files inside AIK-Linux/bin
No error occurs but after flash recovery.img
Phone stuck on boot.

Here is my stock recovery and important files please port
My recovery




https://drive.google.com/file/d/1SkLx_th8esVi1URWs8-16xv6A9dOF-Bi/view?usp=drivesdk

Sent from my Titanium Vista 4G using Tapatalk
 

Augustoandro

Senior Member
Jun 20, 2017
569
266
Pune
Micromax IN Note 1
No error occurs during packing and unpacking but.
After flash recovery.img phones stuck on bootloop.

Sent from my Titanium Vista 4G using Tapatalk

---------- Post added at 02:59 PM ---------- Previous post was at 02:44 PM ----------

No error occurs but after flash recovery.img
Phone stuck on boot.

Here is my stock recovery and important files please port
My recovery




https://drive.google.com/file/d/1SkLx_th8esVi1URWs8-16xv6A9dOF-Bi/view?usp=drivesdk
You already requested on my another thread.
 

Deeni131

Senior Member
Oct 23, 2016
67
8
Yes, I know XDA is filled with such guides.
But you can only port a TWRP if you implement parts of all the guides.
This guide is a summation of all those guides.

NOTE:
I would be using AIK-Linux in this tutorial, since I don't recommend Windows for all this, who knows what problems you will get into.

REQUIREMENTS:
1.Download these TWRP recoveries in accordance with your screen resolution.
A. If your screen resolution is 480x850, 480x854; download
https://twrp.me/devices/lgnexus4.html
B. If your screen resolution is 720x1280, 800x1280 or 720xsomething; download
https://twrp.me/devices/asusnexus720123g.html
C. If your screen resolution is 1080x1920, download
https://twrp.me/devices/motorolanexus6.html
2. Download Android Image Kitchen-Linux from this thread:
https://xdaforums.com/showthread.php?t=2073775

LET'S BEGIN:
1. Unzip Android Image Kitchen zip file.
3. Now, navigate to the unzipped folder of AIK (Android Image Kitchen).
4. Just Right Click and select "Open Terminal here".
5. Copy and paste your stock recovery.img and paste it in AIK folder.
6. In the terminal, type the command
Code:
su
Enter your root password, then type
Code:
./unpackimg.sh
7. This will unpack your stock recovery.img. Do not close the terminal.
8. Cut the new folders, ramdisk and split_img, and paste them somewhere outside of AIK folder.
9. Remove the stock recovery.img in AIK folder.
10. Now, copy and paste the twrp_recovery.img according to your screen resolution in the AIK folder.
11. Now, revert back to the terminal and type
Code:
./unpackimg.sh
12. This will unpack your twrp_recovery.img
13. Delete all the files in the new split_img folder we got by unpackimg twrp_recovery.img
14. Copy and paste all the files in stock split_img folder to the new split_img folder.
15. Delete following files from new ramdisk folder.
A. default.prop
B. fstab.devicename_or_chipsetname
C. ueventd.rc
D. Any other file like ueventd.devicename.rc
16. Copy and paste these files from stock ramdisk folder to new ramdisk folder.
A. default.prop
B. fstab.devicename
C. ueventd.rc
17. Now go into stock ramdisk/etc folder and copy recovery.fstab
18. Paste the recovery.fstab file in new ramdisk/etc folder.
19. Edit the twrp.fstab file according to the newly pasted recovery.fstab
20. You will have to replace"/sdcard" with "/external_sd" and "/usb" with "/usb-otg".
21. If the partitions stated above are not available in your fstab files then add these lines. Order may change on the format in which the files are written.
Code:
/external_sd          vfat         /dev/block/mmcblk1p1  flags=removable;storage;display="SDCARD"
/usb-otg                auto         /dev/block/sda1    flags=removable;storage;display="USB-OTG"
22. Edit the following lines as shown in default.prop
Code:
ro.secure=0
ro.adb.secure=0
security.perf_harden=0
ro.debuggable=1
persist.sys.usb.config=adb,mtp
23. Now, come out of the ramdisk folder and open the terminal.
24. Type
Code:
./repackimg.sh
25. Your new TWRP img would be generated and named as image-new.img by default. You may change the name later.

When you have successfully built the TWRP, or if you want to request one instead of creating yourself, contact me on this thread:
https://xdaforums.com/android/general/unofficial-twrps-devices-source-code-t3833338


SPECIAL INSTRUCTIONS FOR MEDIATEK DEVICES:
1. The recovery.fstab you will get after unpacking your stock recovery.img would be flawed in most cases. I believe OEMs do this deliberately.
2. In order to know which partition is mounted at which location and at which device, you'll need DiskInfo (Install it from Play Store) and a root explorer.
3. Change the Diskinfo settings like this
https://mega.nz/#!fbIR0AoD!ykRMTAitymE4bQMVc6S0qbCYztTkVZDZSgIKcVTxEHg
https://mega.nz/#!yXQzwKJK!rWO_LiKZwFjzw4ZyM0qzzKw6uopxrxAkSkKNRYXVuIY
4. Use the root explorer to find the path of your partitions. They would be located under /dev (mtk devices have bootimg and recovery here generally) and some other partitions like /system, /cache would be deeper inside.
5. You can trace their exact locations by navigating within the /dev directory for partition names like mmcblk0p5.


SPECIAL INSTRUCTIONS FOR DEVICES THAT DON'T HAVE RECOVERY.FSTAB WITHIN STOCK RECOVERY.IMG
1. In the ramdisk/etc folder, there might be a dummy recovery.fstab file with the symbol of link on it.
2. Right click on the file and select "Show Target". You'll get to know the path of original recovery.fstab file. It might be within the unpacked recovery or inside some other partition on your phone.
For example: Honor 7C devices have their recovery.fstab in /vendor/etc folder.



If it works perfectly, I will make it available to others through my thread.
If there are some bugs or you need some assistance in porting TWRP, contact me all the same, we'll work on it to make it bug-free.

CREDITS:
HostZero for his porting guide.
Osm0sis for his awesome Android Image Kitchen


Pls brother help me port twrp for my device. Here is my stock recovery image link : https://drive.google.com/file/d/1dqBU4f0ZXK8Ot0V9t-4Tw6f_60UHg7ca/view?usp=drivesdk.
My phone's resolution : 720 x 1280 pixel.
 
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Augustoandro

Senior Member
Jun 20, 2017
569
266
Pune
Micromax IN Note 1
Last edited:

Leone_1

New member
Dec 16, 2010
3
0
Hi I tried to Port a Recovery for my H96 Max RK3399 TV Box .
I used TWRP From My RK3328 TVBox.
I can Boot in Recovery, but its not Mounting any Partition (everywhere 0MB)
I Think the problem is in .Fstab File but I am Not sure.
I would appreciate help

Sorry for my poor English
 

Augustoandro

Senior Member
Jun 20, 2017
569
266
Pune
Micromax IN Note 1
Hi I tried to Port a Recovery for my H96 Max RK3399 TV Box .
I used TWRP From My RK3328 TVBox.
I can Boot in Recovery, but its not Mounting any Partition (everywhere 0MB)
I Think the problem is in .Fstab File but I am Not sure.
I would appreciate help

Sorry for my poor English
Partitions not being recognized means the problem is in fstab files. Both recovery.fstab and twrp.fstab need to be edited.
I am sure of it.

HIT THANKS IF FOUND USEFUL
 

pizzaboy192

Senior Member
Sep 15, 2010
387
124
Plymouth, MN, USA
Hi,
I have an unofficial TWRP For my phone (Moto G5s+) but it's broken (It mounts system partitions even in read-only mode breaking things, and the current TWRP devs for the devices won't fix it). If I follow your guide and unpack one of these TWRP, I should be able to edit it to leave certain partitions Read Only, right?
 

Augustoandro

Senior Member
Jun 20, 2017
569
266
Pune
Micromax IN Note 1
Hi,
I have an unofficial TWRP For my phone (Moto G5s+) but it's broken (It mounts system partitions even in read-only mode breaking things, and the current TWRP devs for the devices won't fix it). If I follow your guide and unpack one of these TWRP, I should be able to edit it to leave certain partitions Read Only, right?
You have to edit the fstab files for that, look for them in ramdisk/etc folder when you unpack the recovery.

HIT THANKS IF FOUND USEFUL
 
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Reactions: pizzaboy192

Leone_1

New member
Dec 16, 2010
3
0
Partitions not being recognized means the problem is in fstab files. Both recovery.fstab and twrp.fstab need to be edited.
I am sure of it.

HIT THANKS IF FOUND USEFUL

What are you trying to ask?

HIT THANKS IF FOUND USEFUL

must be in the fstab TWRP/Stock the identical partitions?
or this
"/external_sd vfat /dev/block/mmcblk1p1 flags=removable;storage;display="SDCARD"
/usb-otg auto /dev/block/sda1 flags=removable;storage;display="USB-OTG"

only in TWRP.fstab?
 

Augustoandro

Senior Member
Jun 20, 2017
569
266
Pune
Micromax IN Note 1
must be in the fstab TWRP/Stock the identical partitions?
or this
"/external_sd vfat /dev/block/mmcblk1p1 flags=removable;storage;display="SDCARD"
/usb-otg auto /dev/block/sda1 flags=removable;storage;display="USB-OTG"

only in TWRP.fstab?
twrp.fstab and recovery.fstab should be identical, so all you have to do is copy and paste the contents of one into the other after rectifying whatever is wrong with them.

HIT THANKS IF FOUND USEFUL
 
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Reactions: Leone_1

alecxs

Forum Moderator
Staff member
Feb 17, 2016
5,097
8
5,327
gitlab.com
to all people who experience boot loop on TWRP splash screen:
Code:
adb shell
df
you will figure out which mount point is crashing. fix it in fstab. you may have a look in /cache/recovery/last_log too
for me the reason was vold mounts, i simply deleted two lines (yes, its /devices instead of /sys/devices i don't know if it is a bug, its from stock boot.img)
Code:
/devices/mtk-msdc.0/11120000.msdc0* auto vfat defaults voldmanaged=sdcard0:auto
/devices/mtk-msdc.0/11130000.msdc1* auto auto defaults voldmanaged=sdcard1:auto,encryptable=userdata
if touch screen is not working, you can still use touch screen when booted from fastboot (unfortunately no fix, yet):
Code:
fastboot boot <twrp.img>
 

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  • 41
    Yes, I know XDA is filled with such guides.
    But you can only port a TWRP if you implement parts of all the guides.
    This guide is a summation of all those guides.

    NOTE:
    I would be using AIK-Linux in this tutorial, since I don't recommend Windows for all this, who knows what problems you will get into.

    REQUIREMENTS:
    1.Download these TWRP recoveries in accordance with your screen resolution.
    A. If your screen resolution is 480x850, 480x854; download
    https://twrp.me/lg/lgnexus4.html
    B. If your screen resolution is 720x1280, 800x1280 or 720xsomething; download
    https://twrp.me/asus/asusnexus720123g.html
    C. If your screen resolution is 1080x1920, download
    https://twrp.me/motorola/motorolanexus6.html
    2. Download Android Image Kitchen-Linux from this thread:
    https://xdaforums.com/showthread.php?t=2073775

    LET'S BEGIN:
    1. Unzip Android Image Kitchen zip file.
    3. Now, navigate to the unzipped folder of AIK (Android Image Kitchen).
    4. Just Right Click and select "Open Terminal here".
    5. Copy and paste your stock recovery.img and paste it in AIK folder.
    6. In the terminal, type the command
    Code:
    su
    Enter your root password, then type
    Code:
    ./unpackimg.sh
    7. This will unpack your stock recovery.img. Do not close the terminal.
    8. Cut the new folders, ramdisk and split_img, and paste them somewhere outside of AIK folder.
    9. Remove the stock recovery.img in AIK folder.
    10. Now, copy and paste the twrp_recovery.img according to your screen resolution in the AIK folder.
    11. Now, revert back to the terminal and type
    Code:
    ./unpackimg.sh
    12. This will unpack your twrp_recovery.img
    13. Delete all the files in the new split_img folder we got by unpackimg twrp_recovery.img
    14. Copy and paste all the files in stock split_img folder to the new split_img folder.
    15. Delete following files from new ramdisk folder.
    A. default.prop
    B. fstab.devicename_or_chipsetname
    C. ueventd.rc
    D. Any other file like ueventd.devicename.rc
    16. Copy and paste these files from stock ramdisk folder to new ramdisk folder.
    Code:
    default.prop
    fstab.devicename
    ueventd.rc
    17. Now go into stock ramdisk/etc folder and copy recovery.fstab
    18. Paste the recovery.fstab file in new ramdisk/etc folder.
    19. Edit the twrp.fstab file according to the newly pasted recovery.fstab
    20. You will have to replace"/sdcard" with "/external_sd" and "/usb" with "/usb-otg".
    21. If the partitions stated above are not available in your fstab files then add these lines. Order may change on the format in which the files are written.
    Code:
    /external_sd          vfat         /dev/block/mmcblk1p1  flags=removable;storage;display="SDCARD"
    /usb-otg                auto         /dev/block/sda1    flags=removable;storage;display="USB-OTG"
    22. Edit the following lines as shown in default.prop
    Code:
    ro.secure=0
    ro.adb.secure=0
    security.perf_harden=0
    ro.debuggable=1
    persist.sys.usb.config=adb,mtp
    23. Now, come out of the ramdisk folder and open the terminal.
    24. Type
    Code:
    ./repackimg.sh
    25. Your new TWRP img would be generated and named as image-new.img by default. You may change the name later.

    When you have successfully built the TWRP, or if you want to request one instead of creating yourself, contact me on this thread:
    https://xdaforums.com/android/general/unofficial-twrps-devices-source-code-t3833338


    SPECIAL INSTRUCTIONS FOR MEDIATEK DEVICES:
    1. The recovery.fstab you will get after unpacking your stock recovery.img would be flawed in most cases. I believe OEMs do this deliberately.
    2. In order to know which partition is mounted at which location and at which device, you'll need DiskInfo (Install it from Play Store) and a root explorer.
    3. Enable the following Diskinfo settings:
    Code:
    Show mount path
    Show partition name
    Show file system
    Expert mode
    Unmounted partitions
    Device Mapper partitions
    Temporary filesystems

    4. Use the root explorer to find the path of your partitions. They would be located under /dev (mtk devices have bootimg and recovery here generally) and some other partitions like /system, /cache would be deeper inside.
    5. You can trace their exact locations by navigating within the /dev directory for partition names like mmcblk0p5.


    SPECIAL INSTRUCTIONS FOR DEVICES THAT DON'T HAVE RECOVERY.FSTAB WITHIN STOCK RECOVERY.IMG
    1. In the ramdisk/etc folder, there might be a dummy recovery.fstab file with the symbol of link on it.
    2. Right click on the file and select "Show Target". You'll get to know the path of original recovery.fstab file. It might be within the unpacked recovery or inside some other partition on your phone.
    For example: Honor 7C devices have their recovery.fstab in /vendor/etc folder.

    TROUBLESHOOTING INSTRUCTIONS:
    1. If you get a dm-verity error or facing an encryption problem, go to this thread and flash the "dm-verity and forceencrypt disabler zip".
    https://xdaforums.com/android/software/universal-dm-verity-forceencrypt-t3817389
    2. If you encounter a bootloop while booting into your new TWRP, please consult post #20 of this thread.
    3. At times, the path of partitions during recovery boot is not the same as those during normal boot. That's why you may get errors like
    Code:
    Updating partitions details...
    Failed to mount '/cache' (Invalid argument)
    Failed to mount '/system' (Invalid argument)
    Failed to mount '/data' (Invalid argument)
    Failed to mount '/metadata' (Invalid argument)
    ...done
    Unable to mount storage
    Failed to mount '/data' (Invalid argument)
    To resolve this, in your TWRP terminal type the following command
    Code:
    find /dev/block -name by-name
    Replace the paths of the partitions in your fstab files with the ones you get as output using the command above (only the partitions which failed to mount).

    If there are some bugs or you need some assistance in porting TWRP, contact me by mentioning in your post, for example @Augustoandro, we'll work on it to make it bug-free.

    Special thanks to @aIecxs for his troubleshooting instructions of bootloop, "Failed to mount /partition_name (invalid argument)" error and also @inguna for guiding me on how to fix the "SDCARD not detected by the TWRP" problem and also fixing the MTP, ADB not working issue.
    Another thanks to @seanybiker and @avirus for their troubleshooting instructions on "DM-Verity and forceencrypt" errors.

    CREDITS:
    @HostZero for his porting guide.
    @osm0sis for his awesome Android Image Kitchen
    @Zackptg5 for his "DM-Verity and Forceencrypt disabler zip".
    4
    Can't find fstab.devicename in stock ramdisk folder. btw phone is samsung a41 (sm-a415f) @Augustoandro
    This happens sometimes. Some devices directly reference the recovery.fstab file instead of fstab.devicename.
    Edit the rest of the files and proceed further.

    HIT THANKS IF FOUND USEFUL
    3
    @JLowe
    I apologize for the delay in replying.

    1. The topmost part
    Code:
    #<src> <mnt_point> <type> <mnt_flags>
    has already been commented out by "#", so leave it as it is.
    2. For listing the system partition in fstab files, always use "/system".
    3. Always include all entries from the stock recovery.fstab in your TWRP recovery.fstab and edit your twrp.fstab in accordance with it.
    4. Whatever partititon is not available in your stock, never include it in your TWRP fstab (applies to both recovery.fstab and twrp.fstab). If you can't find a partition neither in your stock fstab nor via DiskInfo , it just means those partitions don't exist on your device.
    5. Never include files not available in your stock recovery to your TWRP.

    HIT THANKS IF FOUND USEFUL
    2
    Thanks a lot @Augustoandro! IMHO this is by far the easiest guide for porting TWRP to unsupported devices. Keep it up!
    2
    Hi I tried to Port a Recovery for my H96 Max RK3399 TV Box .
    I used TWRP From My RK3328 TVBox.
    I can Boot in Recovery, but its not Mounting any Partition (everywhere 0MB)
    I Think the problem is in .Fstab File but I am Not sure.
    I would appreciate help

    Sorry for my poor English
    Partitions not being recognized means the problem is in fstab files. Both recovery.fstab and twrp.fstab need to be edited.
    I am sure of it.

    HIT THANKS IF FOUND USEFUL