boot_mac68k - mac68k-specific system bootstrapping procedures
Power fail and crash recovery
Normally, the OpenBSD kernel on the mac68k architecture is
booted from
the native operating system by means of an application program. When the
kernel takes over, it initializes itself and proceeds to
boot the system.
An automatic consistency check of the file systems takes
place, and unless
this fails, the system comes up to multi-user operations. The proper
way to shut the system down is with the shutdown(8) command.
If the system crashes, it will enter the kernel debugger,
ddb(4), if it
is configured in the kernel. If the debugger is not present
or has exited,
the system will attempt a dump to the configured dump
device (which
will be automatically recovered with savecore(8) during the
next boot cycle).
After the dump completes (successful or not), the
system will attempt
a reboot.
On most mac68k machines with ``soft-power'' after the IIcx,
the power
switch can be physically rotated and locked in the ``on''
position. The
native OS can be configured to automatically start the
OpenBSD boot program.
Additionally, the OpenBSD boot program can be configured to boot
OpenBSD without intervention. When a system is so configured, it can
crash or lose power and reboot back to a fully multi-user
state without
any intervention.
The boot application [Toc] [Back]
The boot application runs in the native OS on the system.
It has a dialog
where booting preferences may be changed and an option
whereby these
options may be saved. The preferences are stored in the
program itself,
not in a preferences folder, thus allowing two separate
copies of the
program to be configured differently (e.g., to boot different bsd or
bsd.test, or to boot from two different drives).
One option that may be specified is a boot to single-user
mode. This
stops the boot process very early on and allows system maintenance. If
one wishes to provide some security at this phase of the
boot, remove the
``secure'' option from ttye0 in the ttys(5) file.
Another useful option that may be specified is the ``serial
console'' option.
This will allow a serial device (terminal or computer) to act as a
console for the system. This device must be configured to
use 9600 baud,
eight bits, no parity, and one stop bit (9600-8N1). Either
the printer
port or the modem port (tty01 and tty00, respectively) may
be used for
this.
It is sometimes useful to boot a kernel that resides in a
folder in native
OS rather than from the usual location in the OpenBSD
file system.
A radio button is supplied for this purpose. Note that some
programs
will not run properly if the kernel is not found as /bsd
within the
OpenBSD file system.
/bsd system kernel
ddb(4), ttys(5), savecore(8), shutdown(8)
OpenBSD 3.6 July 1, 1995
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