**Android Phone System Command**
a) Fastboot unlock
adb devices
adb reboot bootloader
fastboot oem unlock
fastboot reboot-bootloader
b) Update the whole android system
adb reboot bootloader
fastboot flash bootloader [bootloader file].img
fastboot reboot-bootloader
fastboot flash radio [radio file].img
fastboot reboot-bootloader
fastboot flash recovery [recovery file].img
fastboot flash boot [boot file].img
fastboot flash system [system file].img
c) Flash the whole system, Update all with Flash-all (Nexus)
fastboot -w update [image file].zip
d) Flash Recovery Imag TWRP, https://twrp.me/Devices/
fastboot flash recovery twrp.img
e) Flash Supersu.zip with TWRP boot to make android rooted
Stable version of SuperSU https://download.chainfire.eu/696/SuperSU/UPDATE-SuperSU-v2.46.zip \\
Beta version of SuperSU https://download.chainfire.eu/740/supersu
adb push Desktop/SuperSu.zip /sdcard/
adb reboot recovery
f) Mount the android image on Linux
mount -t ext2 -o loop userdata.img /mnt/userdata