Rpi3B+ Save U-boot Env to boot form SSD?

Hi there !

I know there is a way to move data from sd to SSD drive plugged on a USB port.

In a GitHub HA post (*) there is a way to boot directly from SSD without any SD card on an ‘old’ RPi 3B+

The only problem is that U-Boot need a certain env variable to do so but we cannot find the right command to permanently save env variable to the U-Boot which means we have to set it each time we reboot the RPi…

I have no knowledge about UBoot so if there is any ‘expert’ we’re all ears to learn.
PS ‘env save’ does not work.


PS So far steps are :
1- Write HA image to SSD (with RPi imager)
2- Activate USB boot on your RPi (look for : “program_usb_boot_mode=1” on the net)
3- Remove SD card and leave SSD plugged
4- Power on RPi with keyboard and screen
5- U-Boot fails to find bootable storage
6- Enter the following code to let uboot ‘find’ usb storage (wait for 4000ms)

‘set env usb_pgood_delay 4000’

7- Reset USB with this command

‘usb reset’

8- (optional) It should detect the usb storage, you could check it with this command :

‘usb storage’

9- Now you can boot from it using :


==> Steps 6 to 9 should be done on each RPi restart/power off

(*) Source : U-Boot fails to boot from USB SSD sometimes on RPi 3b+ · Issue #1712 · home-assistant/operating-system · GitHub

UBoot doc : env command — Das U-Boot unknown version documentation

Frankly the SSD use version where it boots from the SD and never writes to it, then does all it’s stuff in the SSD is fine also. It’s writing to the SD that wears it out, not reading it.

This is where I learned how to do my pi’s (for octoprint in my case) This is a search link into his stuff.

Yes that’s what I’ve been using so far (untill my data HDD started to show weakness and decided to switch to a SSD).

The challenge is more technical than a real ‘need’ (even if I will be able to re use the SD card on other device).

And at the same time I’ll be exploring an unknown domain (for me) which is the boot loader.

Thanks any way for your feedback.