NAME
boot —
system bootstrapping
procedures
DESCRIPTION
Power fail and crash
recovery
Normally, the
NetBSD 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 the debugger is 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 is complete (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
NetBSD
boot program. Additionally, the
NetBSD boot program
can be configured to boot
NetBSD 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
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 netbsd or netbsd.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-N81). 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
NetBSD 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
/netbsd within the
NetBSD file
system.
FILES
- /netbsd
- system kernel
SEE ALSO
ddb(4),
ttys(5),
savecore(8),
shutdown(8)