I have a working Armbian SD card and I used it for some time made some changes in the system (disabled some services, installed some libraries and made new services etc...). I use this SD card with Cubieboard-3 (Cubietruck). And I have a backup of the entire root filesystem from that SD card. Now I've got second Cubieboard-3 device and I need a second SD card to boot the second device into the same OS with actual changes. The good approach would be to backup only CHANGES in some manner that would allow me to install fresh armbian to new SD card and them roll my changes to it. But instead, i started a stupid approach of doing this: just copied the entire filesystem to backup and to a second SD card. Then I inserted the SD card to my Ubuntu laptop, ran Gparted and made the partition bootable. This had no happy end: device didnt booted from the new SD card. As I understand, i must flash U-Boot into it somehow. Maybe reading this https://linux-sunxi.org/U-Boot would help me, but I have no idea is it the good path to go (clone U-Boot, install cross-compiler, compule U-Boot, flash the U-Boot). Is there any easier way? Maybe pre-compiled U-Boot for the cortex-a7 and some instructions for flashing it? All this seems interesting, because i always wanted to dive into some low-level linux stuff, but the time waste too much for now.
