Installing OpenBSD 7.6 on a Raspberry Pi 4?

April 8, 2025

I’ll save you some time: just read the official documentation. I did it the hard way—starting with ChatGPT for instructions, and then diving into blog posts for solutions when things went wrong.

When I plugged the SD card with miniroot76.img into my Raspberry Pi, I’d briefly see the OpenBSD BOOTAA64 boot> prompt, only to have the screen go blank seconds later.

I attempted:

• Modifying config.txt in the boot partition to force safe HDMI configuration
• Using an older version of OpenBSD. The oldest I could find was 7.0
• Changing the boot order so that I could use a USB stick instead of an SD card
• Using the full installation image (install76.img ) instead of miniroot76.img

Nothing worked. I knew using the serial console was a possibility, but I did not have the cable. The installation instructions I found online kept getting more unhinged. When I landed on an 18 step guide requiring two USB sticks and an SD card, I knew it was time to throw in the towel. Luckily I had a NUC to use instead.

In case you still want to use a Pi, the official installation instructions has the answer. Under Install on Raspberry Pi::

…note that once the kernel has started running, by default you will only see output on the serial console. To switch to displaying on the monitor instead, watch for the OpenBSD BOOTAA64 “boot>” prompt, and type “set tty fb0”.

Problem solved.

Written by Martin Camacho