Backup and Restore OnePlus 6 Nandroid and EFS


OnePlus 6’s custom development is in a full swing at the moment. A handful of custom kernels, custom ROMs, MODs and tweaks have come out for this device. The OnePlus 6 community has warmly welcomed all the goodies. Users have started flashing new custom OS on their phones. As the OnePlus 6 are performing various experiements on the device, they are also reporting the issues popping up. Many OnePlus 6 users corrupted their data which demanded an immediate restoration of the Nandroid backup.Backup and Restore OnePlus 6 Nandroid and EFS

Some of the users reported Null IMEI after flashing a custom ROM. The Null IMEI determines a corrupt EFS partiition, which means the phone is no longer capable of making calls and sending text messages. To avoid such issues, the OnePlus 6 users are advised to backup the Nandroid and EFS partition.


Backing up Nandroid and EFS are the two most essential things for the Android users. Both these terms are popular among the custom ROM enthusiasts and everyone else who loves to modify an Android phone. Nandroid and EFS should not conern if you do not modify you do not modify your device by means of root access or a custom recovery. These are essential only for those who like flashing new custom ROMs, or install new MODs that can modify the system.

Nandroid backup includes a backup of your phone’s entire system. It is basically an image of your phone’s current operating system. Nandroid backup includes all the data, all the apps, all the settings and everything else that was a part of your phone. Creating a Nandroid backup can take a lot of time, but it is totally worth that time. The Nandroid backup minimizes the risk of losing data even when you have completely soft-bricked your device.

EFS – Encrypted File System

On the other hand, the EFS partition has an important role as well. The EFS partition stores all your mac addresses, the radio addresses and codes for the WiFi, Bluetooth, and GSM services. Corruption of EFS partition directly hits the IMEI. If you start seeing null or 0000 instead of the original IMEI, it means that the EFS partition is no longer safe. Backing up this partition can save your phone a life. If you happen to lose the EFS parititon, and you had created a backup previously, you are going to get the phone making capabilities of your OnePlus 6 without any pain.

Let’s get back to our post now. This post is about creating a OnePlus 6 Nandroid and EFS Backup. I will show you how to create a Nandroid and EFS Backup on the OnePlus 6 via TWRP recovery. Installing the TWRP custom recovery on the phone is quite easy. If you don’t already have the TWRP recovery, you can follow the tutorial given on our site to install one. Follow these simple steps to backup your OnePlus 6’s Nandroid and EFS partitions now.

Backup and Restore OnePlus 6 Nandroid and EFS

Backup OnePlus 6 Nandroid

  1. Download and install TWRP custom recovery on OnePlus 6.
  2. Now turn off your phone completley.
  3. Turn on the phone by pressing and holding Volume Up + Power button.
  4. Your phone will now boot into the bootloader mode.
  5. Select Recovery mode by pressing Volume Down button, use Power button to execute.
  6. As your phone boots into TWRP recovery, unlock it.
  7. Now click on the Backup button in TWRP.
  8. Select Nandroid and EFS and then create the Backup.
  9. It will take some time for your phone to perform the backup.
  10. The backup will be stored in a folder in your phone’s internal memory.
  11. Copy the backup to your computer for safety measures. That’s all.

Restore OnePlus 6 Nandroid

  1. Boot your phone into TWRP recovery mode.
  2. Tap the Restore menu in TWRP.
  3. Now select the Nandroid backup partitions that you want to restore.
  4. Swipe the screen to start the restore process.
  5. It will take a few minutes for your phone to fully restore. That’s all.

Backup OnePlus 6 EFS

  1. Make sure that your OnePlus 6 is rooted.
  2. Download and install Terminal Emulator for Android on your phone.
  3. Now enter the following commands in Terminal Emulator
    1. su
      1. This command will ask for root permission, grant it.
    2. dd if=/dev/block/sdf2 of=/sdcard/modemst1.bin bs=2048
    3. dd if=/dev/block/sdf3 of=/sdcard/modemst2.bin bs=2048
  4. You will now get two files named modemst1.bin and modemst2.bin in your phone’s internal storage. Copy these files to your computer as well.

Restore OnePlus 6 EFS

  1. Download and install Minimal ADB and Fastboot drivers.
  2. Copy the files modemst1.bin and modemst2.bin to the Minimal ADB and Fastboot Drivers folder.
  3. Enable USB Debugging on your OnePlus 6.
  4. Open Minimal ADB and Fastboot.exe file from your desktop now.
  5. Now in the command window, enter the following commands.
    1. adb reboot bootloader
    2. fastboot flash modemst1 modemst1.bin
    3. fastboot flash modemst2 modemst2.bin

That’s all. If you have any queries, feel free to drop them in the comments section below.

Usama is a software engineer by profession and at he uses his expertise to solve everyday consumer tech problems with his main areas of interest being Android, iOS and Windows.

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