Thanks for the previous posts! I'm having the same issue. I cloned an SD card to set up a second Rock64 board and have duplicate MAC addresses. But I'm now confused as the proper solution.
First, removing cloned-mac-address from the network connections file in /etc/NetworkManager/system-connections/'Wired connection 1.nmconnection' does not work for me, either. When I reboot, that line is missing, still, but my MAC address is unchanged.
Second, I then see some folks fix this in /etc/network/interfaces with:
auto eth0
iface eth0 inet dhcp
hwaddress ether b6:09:a4:06:01:2c
That works for me, also. But... what's the proper way to automate this. That is, I 'm setting up a master SD card that I'll then want to replicate to put into new boards and I need them all to come up with different MAC addresses just like they would if I booted from a fresh Armbian image on each (Or would they? I've not seen this issue, before, but I've not had multiple boards running in parallel, either). What's the proper way to do that? I don't see where the initial MAC address is being set up, or how/where the MAC address is determined in that case.
Thanks!
