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NEXTBOOT(8)		FreeBSD	System Manager's Manual		   NEXTBOOT(8)

NAME
     nextboot -- specify an alternate kernel and boot flags for	the next
     reboot

SYNOPSIS
     nextboot [-e variable=value] [-f] [-k kernel] [-o options]
     nextboot -D

DESCRIPTION
     The nextboot utility allows specifying some combination of	an alternate
     kernel, boot flags	and kernel environment for the next time the machine
     is	booted.	 Once the loader(8) loads in the new kernel information, it is
     deleted so	in case	the new	kernel hangs the machine, once it is rebooted,
     the machine will automatically revert to its previous configuration.

     The options are as	follows:

     -D		 Invoking nextboot with	this option removes an existing
		 nextboot configuration.

     -e	variable=value
		 This option adds the provided variable	and value to the ker-
		 nel environment.  The value is	quoted when written to the
		 nextboot configuration.

     -f		 This option disables the sanity checking which	checks if the
		 kernel	really exists before writing the nextboot configura-
		 tion.

     -k	kernel	 This option specifies a kernel	directory relative to /boot to
		 load the kernel and any modules from.

     -o	options	 This option allows the	passing	of kernel flags	for the	next
		 boot.

FILES
     /boot/nextboot.conf  The configuration file that the nextboot configura-
			  tion is written into.

EXAMPLES
     To	boot the GENERIC kernel	with the nextboot command:

	   nextboot -k GENERIC

     To	enable into single user	mode with the normal kernel:

	   nextboot -o "-s" -k kernel

     To	remove an existing nextboot configuration:

	   nextboot -D

SEE ALSO
     boot(8), loader(8)

HISTORY
     The original nextboot manual page first appeared in FreeBSD 2.2.  It used
     a very different interface	to achieve similar results.

     The current incarnation of	nextboot appeared in FreeBSD 5.0.

AUTHORS
     This manual page was written by Gordon Tetlow <gordon@FreeBSD.org>.

BUGS
     The nextboot code is implemented in the loader(8).	 It is not the most
     throughly tested code.  It	is also	my first attempt to write in Forth.

     Finally, it does some evil	things like writing to the file	system before
     it	has been checked.  If it scrambles your	file system, do	not blame me.

FreeBSD	9.2		       November	19, 2012		   FreeBSD 9.2

NAME | SYNOPSIS | DESCRIPTION | FILES | EXAMPLES | SEE ALSO | HISTORY | AUTHORS | BUGS

Want to link to this manual page? Use this URL:
<http://www.freebsd.org/cgi/man.cgi?query=nextboot&manpath=FreeBSD+9.2-RELEASE>

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