Raspberrypi4

Over the course of 2020, there was much enthusiasum in the Raspberry Pi community over the evolving ability of the Raspberry Pi 4b model’s to boot its operating system ‘directly’ from an external storage device. The ride has been a bit bumpy along the way, but very manageable for the hobbyist to play along.

However, I wanted to bring together four specific components to the equation:

• Ubuntu Server 20.04 LTS 64-bit
• an external SSD as the primary/OS storage device
• and of course, a Raspberry Pi 4b (with non-beta firmware)
• And most importantly, I didn’t want to have to do a lot of ‘afterwork’ to maintain the setup.

Specifically, I didn’t want to have to manually copy a bunch of RPi-specific boot files around to support booting a 64-bit kernel, nor with decompressing the compressed kernel that is generated by default when the Ubuntu kernel is updated in the normal course of maintenance. I believe that I may have waited just long enough for the Raspberry Pi firmware to have sufficiently matured to solve the former concern, while the scripting shown below will solve the latter concern.