The OpenBSD kernel is started by placing it at the beginning of physical memory and transferring to the entry point. Since the system is not reenterable, it is necessary to read it in from disk or tape each time it is to be bootstrapped.
Power fail and crash recovery.
Normally, the system will boot itself at power-up or after crashes. An automatic consistency check of the file systems will be performed, and unless this fails, the system will resume multi-user operations. If this variable is set to h , the ROM prints a prompt on the console and waits for user commands. If set to b , the ROM attempts to autoboot. On the DECstation 2100 and 3100, the path used for automatic booting is stored in the bootpath environment variable.