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kernel(1M)		System Administration Commands		    kernel(1M)

       kernel  - UNIX system executable	file containing	basic operating	system

       kernel-name [-afsrvx]

       The operating system image, or kernel, is the  collection  of  software
       comprising the image files (unix	and genunix) and the modules loaded at
       any instant in time. The	system will not	function without a  kernel  to
       control it.

       The kernel is loaded by the boot(1M) command in a machine-specific way.
       The kernel may be loaded	from disk, CD-ROM, or DVD (diskfull  boot)  or
       over the	network	(diskless boot). In either case, the directories under
       /platform and /kernel must be readable and must contain executable code
       which is	able to	perform	the required kernel service. If	the -a flag is
       given, the user is able to supply different pathnames for  the  default
       locations  of the kernel	and modules. See boot(1M) for more information
       on loading a specific kernel.

       If the kernel name is not explicitly specified, then on systems capable
       of  supporting the 64-bit kernel, the boot program will attempt to load
       the 64-bit kernel in preference to the 32-bit kernel  by	 default.  See

       The moddir variable contains a colon-separated list of directories that
       the kernel searches for modules.	moddir can be set in  the  /etc/system
       file.   The  minimal  default  is  /platform/platform-name/kernel:/ker-
       nel:/usr/kernel,	but this default they  be  overridden  by  a  specific
       platform.  It  is  common for many systems to override the default path


       where platform-name can be found	using the -i option of	uname(1),  and
       hardware-class-name can be found	using the -m option of uname(1).

       The  kernel  configuration can be controlled using the /etc/system file
       (see system(4)).

       genunix is the platform-independent component of	the base kernel.

       The following options are supported:

       -a    Asks the user for configuration information,  such	 as  where  to
	     find  the system file, where to mount root, and even override the
	     name of the kernel	itself.	Default	responses will be contained in
	     square  brackets ([ ]), and the user may simply enter <RETURN> to
	     use the default response (note that <RETURN> is  labeled  <ENTER>
	     on	 some  keyboards).  To help repair a damaged /etc/system file,
	     enter /dev/null at	the prompt that	asks for the pathname  of  the
	     system configuration file.	See system(4).

       -f    Causes  Autoclient	 systems  to flush and reinitialize the	client
	     system's local cache. This	flag is	ignored	for all	non-Autoclient

       -r    Reconfiguration boot. The system will probe all attached hardware
	     devices and assign	nodes in the file  system  to  represent  only
	     those  devices actually found. It will also configure the logical
	     namespace in /dev as well as the physical namespace in  /devices.
	     See  add_drv(1M) and rem_drv(1M) for additional information about
	     maintaining device	drivers.

       -s    Boots only	to init	level 's'. See init(1M).

       -v    Boots with	verbose	messages enabled. If this flag is  not	given,
	     the messages are still printed, but the output is directed	to the
	     system logfile. See syslogd(1M).

       -x    Does not boot in clustered	mode. This option only has  an	effect
	     when  a version of	Sun Cluster software that supports this	option
	     has been installed.

	See boot(1M) for examples and instructions on how to boot.

	     Contains kernel components	common to all platforms	within a  par-
	     ticular  instruction  set that are	needed for booting the system.
	     of	the core image file.

	     The platform-specific kernel components.

	     The kernel	components specific to this hardware class.

	     Contains kernel components	common to all platforms	within a  par-
	     ticular instruction set.

       The  directories	 in this section can potentially contain the following

       drv   Loadable device drivers

       exec  The modules that execute programs stored in various file formats.

       fs    File system modules

       misc  Miscellaneous system-related modules

       sched Operating system schedulers

	     System V STREAMS loadable modules

       sys   Loadable system calls

       cpu   Processor specific	modules

       tod   Time-Of-Day hardware interface modules

       Additionally,  some  of	the  subdirectories  mentioned	above  contain
       sparcv9	subdirectories that contain 64-bit versions of the same	module
       classes.	 For  example,	/kernel/drv/sparcv9  and  /platform/sun4u/ker-

       mach  IA	hardware support

       See attributes(5) for descriptions of the following attributes:

       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       |Availability		     |SUNWcar, SUNWcarx		   |

       uname(1),   isainfo(1),	 add_drv(1M),  boot(1M),  init(1M),  kadb(1M),
       rem_drv(1M), savecore(1M), syslogd(1M), system(4), attributes(5)

   SPARC Only

       The kernel gives	various	warnings and error messages. If	the kernel de-
       tects an	unrecoverable fault, it	will panic or halt.

       Bugs in the kernel often	result in kernel panics.

       Reconfiguration	boot  does not currently remove	filesystem entries for
       devices that have been physically removed from the system.

SunOS 5.9			  12 Dec 2001			    kernel(1M)


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