With root, you can now back up critical partitions:
adb shell
su
dd if=/dev/block/by-name/system of=/sdcard/system.img
dd if=/dev/block/by-name/vendor of=/sdcard/vendor.img
Since a rooted POS is a security risk, install AFWall+ (IPTables frontend) to block all unnecessary outgoing traffic except your payment gateway. sunmi v2 root
If you need advanced control without rooting: With root, you can now back up critical
The Sunmi V2 runs on a customized version of Android (typically Android 6.0 Marshmallow or Android 7.1 Nougat depending on the specific batch). It is a dedicated commercial device, not a standard consumer phone. Since a rooted POS is a security risk,
Key Hurdles:
On your Sunmi V2: