While SD cards are the most standard method of booting a Raspberry Pi, they are not always suitable for applications that require rapid I/O or lots of I/O. Booting from USB is a feature that aims to help fix these two problems, in addition to inceasing the longevity of your storage.
Please proceed at your own risk. While I personally have not seen a case in which a Raspberry Pi has become "bricked" or inoperable, it is important to keep in mind that when you are altering the
EEPROM you may experience a loss of data or a non-bootable system. We are not responsible/liable if you use this beta software and "brick" your Pi!
- Raspberry Pi (In this example we will be using a Raspberry Pi 4, 4GB)
- USB to SATA adapter
- SATA SSD
- SSDs are recommended for this beacuse they have lower power requirements and are much faster that typical HDDs
- See Known Working SSDs
- SD Card
- Ubuntu 20.04
- Raspberry Pi OS
- Link is to 64 bit which is still in Beta as of this writing.
Booting Raspberry Pi via USB SSD
Before we start it is important to verify that your equipment is functioning correctly. We can do this by first flashing our SD card with Raspberry Pi OS and running it on our Pi. For brevity I will be omitting the process of flashing the SD card since this is a more Advanced guide. If you need help with this, please see Installation.
Once you have booted into Raspberry Pi OS, feel free to connect your SSD to the USB to SATA adapter and plug it into the Pi. I have witnessed issues when using the USB 2.0 ports (the ports that are black), so please use the USB 3.0 ports (blue). After it is plugged in, verify that you can see the drive:
The output from this command should show you a block device, most likely called
sda or something prefaced with
sd. If you don't see your USB SSD immediately, try switching to the other 3.0 USB port, or trying a different USB to SATA cable/adapter.
Once your disk is detected we've confirmed that it is useable by the Pi, so it is safe to disconnect the drive from the Pi.
Awesome! Our disk is detected. Now we move on to the technical stuff...
Updating Pi Firmware
Update Raspberry Pi OS
While your Pi is still booted to Raspberry Pi OS, run a full update on the SD card's OS:
Start Flashing USB SSD
While the update is running, we can go ahead and flash the Ubuntu image onto our SSD. Feel free to unplug it from the Pi and image it how you see fit. It can take a little while, best to get it going while doing other things.
Change Bootloader Branch
With your freshly updated Rasberry Pi OS run the following to check your current bootloader version, making note of the returned version:
Switch the EEPROM firmware branch:
Update Pi Bootloader Settings
Replace the current bootloader configuration settings with the beta ones that allow for USB booting:
This command will prompt you to reboot, so we can do so:
Verify Bootloader Firmware Version
Once you're booted back to the SD card on Raspberry Pi OS, check the bootloader version once again:
This version should be different from the one that was reported before our
Congratulations, your Pi is now able to boot from USB! However, we aren't quite there yet.
Setting Up our SSD for use with USB Booting
I personally found this part easier to do from our Raspberry Pi that I just got done flashing the firmware on. For that reason this section will be written from that perspective, but this should be possible using any Linux-based system.
Drop in Pi-Specific Firmware
Plug in your SSD that has been flashed with Ubuntu 20.04. The
writeable partitions should automatically be mounted to
Change directory to
Run the following one-liner to patch the bootloader on our SSD with the applicable Pi firmware:
Dealing with Compressed Kernel
Copy the compressed Linux kernel to your home directory:
Decompress the Linux kernel:
Copy the decompressed kernel to
Next create a script that will automatically decompress the kernel so that we can reboot the Pi without having to do the previous steps manually every boot:
apt hook that decompresses the kernel on updates:
Make this hook executeable:
Alter the Bootloader Config
Edit the bootloader config in the
[rpi4] section to look like this:
It may be necessary to make an additional parameter if your USB storage is uncharacteristically slow. Just uncomment the
Whew, that was a lot of stuff to do just to make our SSD image bootable! But that's all. From here I suggest shutting down the Pi:
Once the Pi is powered off, remove your SD card, double check to make sure your USB SSD is properly seated, and power it back on.
Your system should now boot from the USB SSD.
Verify SSD Boot
After it's booted give it a minute or so for
cloud-init to complete, and log in with username and password
ubuntu. It will prompt for a password change upon login. From here, we can check to make sure the SSD is mounted properly:
Go ahead and install updates for Ubuntu and reboot:
Verify Reboots are Working
When your host has rebooted, just make sure it boots back into Ubuntu. If it hangs or doesn't make it to the OS, there is something wrong. Feel free to reach out to folks on the Discord if you run into trouble.
A list of products that have been known to work, verified by our Discord community. If you're using different equipment with success, please make a PR to list it!