# Booting a converted RPi3 image from SDD

**URL:** <https://hub.mender.io/t/booting-a-converted-rpi3-image-from-sdd/1690>\
**Category:** General Discussions\
**Created:** [March 25, 2020, 7:35am UTC](https://hub.mender.io/t/booting-a-converted-rpi3-image-from-sdd/1690 "2020-03-25T07:35:24Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![mirzak](https://yyz2.discourse-cdn.com/flex036/user_avatar/hub.mender.io/mirzak/32/2056_2.png) [@mirzak](https://hub.mender.io/u/mirzak)\
**Post date:** [March 25, 2020, 7:35am UTC](https://hub.mender.io/t/booting-a-converted-rpi3-image-from-sdd/1690/1 "2020-03-25T07:35:24Z")

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Got a question from a user and though it would be helpful to answer it here,

> I am able to boot just fine off an sdcard with a converted rpi3 image but not off an SSD. The SSD boots fine with a stock RPI3 image so its not a power issue or SSD issue. Any idea what could be different  
> between booting off a converted sdcard and SSD? I used the same mender recommended dd command to flash both…

What I suspect is happening here is that the storage medium naming changes between SD and SSD.

mender-convert is configured to boot from SD, and hence [this](https://github.com/mendersoftware/mender-convert/blob/master/configs/mender_convert_config#L106) configuration is applied,

```auto
MENDER_STORAGE_DEVICE_BASE=/dev/mmcblk0p

```

Could you try updating this to,

```auto
MENDER_STORAGE_DEVICE_BASE=/dev/sda

```

You can double-check what the name of the storage medium when booting from SDD using a stock Raspbian image.

This naming is needed for Mender to be able to switch between partitions and right now does not support “dynamic” booting.

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<div class="post-metadata">

**Author:** ![mirzak](https://yyz2.discourse-cdn.com/flex036/user_avatar/hub.mender.io/mirzak/32/2056_2.png) [@mirzak](https://hub.mender.io/u/mirzak)\
**Post date:** [March 26, 2020, 9:50am UTC](https://hub.mender.io/t/booting-a-converted-rpi3-image-from-sdd/1690/2 "2020-03-26T09:50:37Z")

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Thinking a bit more about this, I now realize that it is probably not as easy as initially suggested.

On Raspberry Pi 3 we use U-Boot as boot loader which is required to integrate Mender to be able to switch between partitions.

The integration that is done in U-Boot is pretty much hard-coded to to use SD as boot medium. You can find the U-Boot integration [here](https://github.com/mendersoftware/uboot-mender/commits/mender-rpi-2019.01).

To support booting from SSD (from USB) you would need adjust U-Boot to:

- Store the environment on SSD (USB storage) instead of MMC. I am not sure if this is even possible, as SSD is a USB storage device in U-Boot which is a “hot plugged”
- Adjust the [mender\_config\_defines.h](https://github.com/mendersoftware/uboot-mender/commit/ccf5d4f1ccaeffb12dba65963914360d0532ec1f) to match booting from USB instead of SD
- Adjust the boot command script to load files from USB instead of SD
  - This is the `boot.scr` which is generated [here](https://github.com/mendersoftware/mender-convert-integration-scripts/blob/master/build-uboot-rpi.sh#L56-L69)

On a stock Raspbian SSD boot probably works out-of-the-box but this is because they do not use U-Boot.

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**Author:** ![peac](https://yyz2.discourse-cdn.com/flex036/user_avatar/hub.mender.io/peac/32/1200_2.png) [@peac](https://hub.mender.io/u/peac)\
**Post date:** [May 18, 2021, 4:57pm UTC](https://hub.mender.io/t/booting-a-converted-rpi3-image-from-sdd/1690/3 "2021-05-18T16:57:24Z")

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discussion relevant to this topic is also happening in [this topic](https://hub.mender.io/t/pi3-usb-boot-support/595/12)