Hello
how can I read using shell any board unique identifier (that keeps it’s value after flash and after power-up)
Which mangOH board are you concerned with? I think the NFC chip on the mangOH Yellow contains a factory programmed unique identifier, but I’m not aware of any similar identifying piece of information on the mangOH Red or Green.
The cm info command gives you the “FSN” (serial number) of the WP module. That should always be unique, but it isn’t absolutely fixed to the board unless you have a mangOH where the module is soldered on rather than in a socket. If you’re looking for a more programmatic way to get this serial number, then have a look at le_info_GetPlatformSerialNumber() which is part of Legato’s Modem Information API.