Booting an Alternate Kernel

As we’ll cover in tedious detail in Chapter 18, you can configure the OpenBSD kernel, but before you do so, be sure that you can boot alternate kernels. You’ll need to be able to boot a different kernel if, say, you hose your filesystem so badly that it won’t even boot to single-user mode, and you need to recover using the installation kernel.

Booting a Different Kernel File

An OpenBSD installation includes three kernels out of the box: the single-processor kernel /bsd, the multiprocessor kernel /bsd.mp, and the upgrade and install kernel /bsd.rd. (If your machine has multiple processors, the installer renames /bsd to /bsd.sp and /bsd.mp to /bsd.)

To boot a nonstandard kernel, first reboot and interrupt the boot ...

Get Absolute OpenBSD, 2nd Edition now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.