Even so, is it possible to ship with the same MAC address ?
No, that’s your symptom right now.
Please refer to the thread below
“Rock 3a mac generation”
The content is as described by “amazingfate” in the above thread,
If the image generated by the method using “vendor storage” is diverted to multiple boards, the same “MAC Address” will be assigned.
To generate “MAC Address”, you should use the method using “cpu serial number” or “random mac address”.
(I think recent “u-boot” was a way to generate “MAC Address” based on “cpu serial number”…)
That way, the “MAC Address” will be assigned a board-specific value even if you reuse the same image.