But it always change MAC after reboot. And router cant assign reserved IP.
In previous versions of datrhs Libreelec firmware the following solution did not work. It seems to work in the latest version dated 02/02/2019 on both my X8-H Plus and X8.
Solution
Open a file manager on your computer and browse to the following folder on your Minix X8(-HP)
\\LibreElec-x8hp\Configfiles\udev.rules.d
(I named my X8-H Plus 'LibreElec-x8hp' to distinguish between my two minixes.)
Create a new file and call it e.g.:
99-Mac-address.rules
(You can name it anything you want, but it is a good habit to use a descriptive name, hence 'mac-address'. The number '99' is not really necessary. It is just there to make sure this rule is applied after all, if any, of the other rules have been applied.)
Next, open the file in a text editor and copy and paste the following two lines into it:
SUBSYSTEM=="net", KERNEL=="eth0", RUN+="/sbin/ip link set dev %k address 11:12:13:14:15:16"
SUBSYSTEM=="net", KERNEL=="wlan0", RUN+="/sbin/ip link set dev %k address 11:12:13:14:15:17"
(You can use any MAC address, as long as it is not used by other hardware in your network.)
Save the file and reboot your Minix device.
On my Windows computer I then use Wireless Network Watcher (wnetwatcher.zip) to check the MAC address. Once you have verified that it is the MAC address you set, you can open the user interface of your router and assign an IP address to the Minix.