# Booting a converted image from USB

**URL:** <https://hub.mender.io/t/booting-a-converted-image-from-usb/4197>\
**Category:** General Discussions\
**Tags:** raspberry-pi-4, boot, usb\
**Created:** [October 18, 2021, 4:48pm UTC](https://hub.mender.io/t/booting-a-converted-image-from-usb/4197 "2021-10-18T16:48:22Z")\
**Posts on this page:** 1\
**Showing post:** 5

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**Author:** ![sdynes](https://avatars.discourse-cdn.com/v4/letter/s/cc9497/32.png) [@sdynes](https://hub.mender.io/u/sdynes)\
**Post date:** [October 21, 2021, 6:33pm UTC](https://hub.mender.io/t/booting-a-converted-image-from-usb/4197/5 "2021-10-21T18:33:51Z")

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I spent more time tracking down this issue, and my current thinking is that the challenge is in the u-boot boot.scr. Even when setting the MENDER\_STORAGE\_DEVICE etc. as /dev/sda, the u-boot boot.scr has:

mmc dev ${mender\_uboot\_dev}

where the mmc tries to load the image from an SD card, which I’m trying to not use.

Are there switches or config files where I can get the boot.scr file generated with the needed USB command, e.g.

ums 0 usb 1:2?

Or is the expectation that there will always be an SD card for the U-boot, which might then point to an USB drive for the second A/B images?

Thanks!

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_[View the full topic](https://hub.mender.io/t/booting-a-converted-image-from-usb/4197)._