config kernel editor is great when you know what you’re doing, but many of us aren’t that lucky or educated. When I’m trying to figure out how to fix a problem, I’ll frequently make a change, reboot to test the change, and see if things work.
OpenBSD lets you edit the kernel at boot time. You can try one boot with a kernel change, see if it works, and write your changes to the kernel. At the boot loader prompt, run
boot > boot -c
You’ll get a couple lines of boot output, and then the kernel editor prompt.
This works just like the
config kernel configuration editor. Make any changes you want here, exactly as you would with
config. When you
quit the editor, the kernel should boot with the changes ...