Advanced users • Is there a way to get RPi5 to boot from a specific USB device if multiple USB devices are connected ?

I plan to use my RPi5 to execute regressiontests for raspiBackup. As of now I use a desktop and QEMU to execute the regessiontest which is quite slow

The regression flow I think of is as follows:

1) RPi boots from SD card
2) RPi creates a backup of itself on an attached USB disk - the backup disk
3) RPi restores the backup to another attached USB disk - the restore disk
4) RPi5 modifies the boot sequence to boot from USB the restored backup on the restore disk
5) RPi5 reboots from the restore disk
6) The restored system executes some sanity tests and finally modifies the boot sequence to boot from SD card again
7) RPi5 reboots from the SD card and continues to test other backup options

This will only work if it's possible to configure RPi5 to USB boot from the restore disk instead of the backup disk. This will also work if there is some USB boot device selection algorithm, for example the USB slots are polled in a deterministic sequence for existing USB devices and I connect the restore disk in the USB slot which will be polled first.

Would be great if this feature exists or do I have to find another way to execute the regressiontest on my RPi5?

Statistics: Posted by framp — Tue Mar 11, 2025 3:52 pm

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