Unlocking mia1 bootloader with fastboot

Warning: Unlocking bootloader may brick or void your device warranty. Use at your own risk.

1. Turn on USB debugging in developer options.

2. Power off device then press and hold volume - key to enter fastboot.

3. Connect to any Linux system which has fastboot installed.

[root@server ~]# fastboot --version
fastboot version e7195be7725a

4. Check the device if it’s detected by fastboot.

[root@server ~]# fastboot devices
e4a26a61 fastboot

5. Unlock the boot loader.

[root@server ~]# fastboot oem unlock
...
OKAY [  0.030s]
finished. total time: 0.030s

6. Reboot the device.

[root@server ~]# fastboot reboot
...
OKAY [  0.030s]
finished. total time: 0.030s

7. To relock the bootloader use lock command.

[root@server ~]# fastboot devices
e4a26a61 fastboot

[root@server ~]# fastboot oem lock
...
OKAY [  0.032s]
finished. total time: 0.032s

8. Reboot the device.

[root@server ~]# fastboot reboot
rebooting...
finished. total time: 0.070s