# Does a Mender image change the RPi Serial Number?
**URL:** https://hub.mender.io/t/does-a-mender-image-change-the-rpi-serial-number/3030
**Category:** General Discussions
**Tags:** raspberry-pi-zero-wifi
**Created:** [December 31, 2020, 5:11pm UTC](https://hub.mender.io/t/does-a-mender-image-change-the-rpi-serial-number/3030 "2020-12-31T17:11:33Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@martind](https://hub.mender.io/u/martind)
#### Post date: [December 31, 2020, 5:11pm UTC](https://hub.mender.io/t/does-a-mender-image-change-the-rpi-serial-number/3030/1 "2020-12-31T17:11:33Z")
I have a golden Debian image and a Mender converted image (based on the golden Debian one).
In my testing I noted that the serial number reported on the terminal are different for the same Pi (specifically a Pi Zero W).
It doesn’t make sense to me but my assumption is the Serial number field cannot be edited. Perhaps the serial number field is not a static value. Can anyone explain why the serial number would be different based on using a Debian image vs a Mender converted image? Also is there a way to ‘disable’ or prevent this from happening.
From Mender converted image
```auto
pi@raspberrypi:~ $ cat /proc/cpuinfo
processor : 0
model name : ARMv6-compatible processor rev 7 (v6l)
BogoMIPS : 697.95
Features : half thumb fastmult vfp edsp java tls
CPU implementer : 0x41
CPU architecture: 7
CPU variant : 0x0
CPU part : 0xb76
CPU revision : 7
Hardware : BCM2835
Revision : 9000c1
Serial : 00000000b802b645
Model : Raspberry Pi Zero W Rev 1.1
```
From golden Debian based image without Mender
```auto
pi@raspberrypi:~ $ cat /proc/cpuinfo
processor : 0
model name : ARMv6-compatible processor rev 7 (v6l)
BogoMIPS : 697.95
Features : half thumb fastmult vfp edsp java tls
CPU implementer : 0x41
CPU architecture: 7
CPU variant : 0x0
CPU part : 0xb76
CPU revision : 7
Hardware : BCM2835
Revision : 9000c1
Serial : 00000000fc9474b4
Model : Raspberry Pi Zero W Rev 1.1
```
Thanks and Happy New Year!
---
### Author:  [@dellgreen](https://hub.mender.io/u/dellgreen)
#### Post date: [December 31, 2020, 6:13pm UTC](https://hub.mender.io/t/does-a-mender-image-change-the-rpi-serial-number/3030/2 "2020-12-31T18:13:15Z")
I don’t know much about Pi, but I would first check the contents of the serial number OTP register in the SOC to see what that value is.
[https://www.raspberrypi.org/documentation/hardware/raspberrypi/otpbits.md](https://www.raspberrypi.org/documentation/hardware/raspberrypi/otpbits.md)
---
### Author:  [@martind](https://hub.mender.io/u/martind)
#### Post date: [December 31, 2020, 9:16pm UTC](https://hub.mender.io/t/does-a-mender-image-change-the-rpi-serial-number/3030/3 "2020-12-31T21:16:49Z")
So the serial register dump you suggested (from the Mender image) matches the serial number on the standard Debian image. I guess I’ll find a way to retrieve this value in my program to identify the device and not use /proc/cpuinfo. I was worried when I saw the serial number change between version 😉
Thanks!
---
### Author:  [@dellgreen](https://hub.mender.io/u/dellgreen)
#### Post date: [December 31, 2020, 11:34pm UTC](https://hub.mender.io/t/does-a-mender-image-change-the-rpi-serial-number/3030/4 "2020-12-31T23:34:51Z")
awesome, it does beg the question, what mender-convert is doing/not-doing that’s causing the kernel to not use the SOC serial number. It might worth double checking your mender-convert configuration and documentation, to ensure that you are using the necessary configs and overlays required for a raspberry-pi conversion (they may add extra kernel parameters for example)