Single-user mode is the earliest point when OpenBSD can give you a Unix-style shell prompt. At this point, the kernel has probed all the hardware, attached drivers to all the hardware that it’s going to acknowledge, and started
init. The system hasn’t mounted any filesystems except for the root partition, which is mounted in read-only mode. The network isn’t started, no services are running, security is not implemented, and filesystem permissions are ignored.
To boot OpenBSD in single-user mode, enter
boot -s at the loader prompt.
boot> boot -s
Why would you want to boot into single-user mode? If your computer has a problem that is preventing it from booting, you should be able to access single-user mode and fix the ...