Aruba AP-105 same boot image, same MAC

Hello, I have some AP-105 units. With the first one I had problems reading the flashrom correctly. It was incomplete. I took the next device, read the flashrom successfully and transferred it to the flashrom of the first device. With a hex editor I changedd the ethernet-mac and the serial number in the flashrom file.

When I start the first router under OpenWrt, it shows me the ethernet-mac-address of the second router. Not the one I changed in the flashrom.

hexdump -C /dev/mtd6 |grep f3:f7:ca shows me the correct mac entered by me in the flashrom file.

Does anybody have a hint where I could look up to change the mac address?

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I'm wondering the same thing. I originally set about to see if I could convert a plain AP-105 to the much more useful IAP-105 which has a built in virtual controller. I dumped the flash form a real IAP-105 and loaded it onto the AP-105 guinea pig and it was successful, it came up as an IAP-105 and worked perfectly so that proves the hardware is indeed identical. There is a problem though, it is a complete clone of the real IAP, all the same MAC addresses and such. That won't matter for using it in a separate installation but obviously it's not going to work with the IAP I cloned it from.

So then I came across the OpenWRT support for the AP-105 and decided to have a go with that. Installation was simple enough and worked on the first try booting up OpenWRT. I checked and confirmed that the MAC addresses match those from the IAP image I started out with so OpenWRT (or U-boot) is clearly aware of the location where this data is stored and able to access it. But where is it stored? Like the OP here I did find the MAC in the IAP firmware image using a hex editor but changing it had no apparent effect.

This is really more of an academic exercise than a real need but it's bugging me, I know it must be possible but every path I've tried has been a dead end.

Nobody knows? Surely somebody had to have this knowledge in order to port OpenWRT to the AP-105 in the first place?

check at offset 0xfe001c

Editing in the HEX editor:
Delete cache areas
Note --> recognizable at the beginning with "TheCache"/"54 68 65 43 61 63 68 65"
addresses :
00F80000 to
mark and set to HEX 00 (fill selection)

Enter the desired MAC address:
e.g. 12:34:56:78:ab:cd
Insert from the specified address accordingly:
00fe001c 12345678abcd Data Type: Hexadecimal
00ff008e 12:34:56:78:ab:cd Data Type: Decoded text

After restart, the MAC is 00:00:00:00:00:00:00
Even if the MAC has been changed correctly, update the firmware in the
update the firmware in the Aruba interface
Translated with (free version)

Bearbeitung im HEX-Editor:
Cachebereiche löschen
Hinweis --> erkennbar an Beginn mit "TheCache"/"54 68 65 43 61 63 68 65"
dazu Adressen
00F80000 bis
markieren und auf HEX 00 setzen (Auswahl füllen)

gewünschte MAC-Adresse eintragen:
z.B. 12:34:56:78:ab:cd
ab angegebener Adresse entsprechend einsetzen:
00fe001c 12345678abcd Data Type: Hexadezimal
00ff008e 12:34:56:78:ab:cd Data Type: Dekodierter Text