xref: /freebsd/stand/common/help.common (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1################################################################################
2# Thelp DDisplay command help
3
4	help [topic [subtopic]]
5	help index
6
7	The help command displays help on commands and their usage.
8
9	In command help, a term enclosed with <...> indicates a value as
10	described by the term.  A term enclosed with [...] is optional,
11	and may not be required by all forms of the command.
12
13	Some commands may not be available.  Use the '?' command to list
14	most available commands.
15
16################################################################################
17# T? DList available commands
18
19	?
20
21	Lists all available commands.
22
23################################################################################
24# Tautoboot DBoot after a delay
25
26	autoboot [<delay> [<prompt>]]
27
28	Displays <prompt> or a default prompt, and counts down <delay> seconds
29	before attempting to boot.  If <delay> is not specified, the default
30	value is 10.
31
32################################################################################
33# Tboot DBoot immediately
34
35	boot [<kernelname>] [-<arg> ...]
36
37	Boot the system.  If arguments are specified, they are added to the
38	arguments for the kernel.  If <kernelname> is specified, and a kernel
39	has not already been loaded, it will be booted instead of the default
40	kernel.
41
42################################################################################
43# Tbcachestat DGet disk block cache stats
44
45	bcachestat
46
47	Displays statistics about disk cache usage.  For debugging only.
48
49################################################################################
50# Techo DEcho arguments
51
52	echo [-n] [<message>]
53
54	Emits <message>, with no trailing newline if -n is specified.  This is
55	most useful in conjunction with scripts and the '@' line prefix.
56
57	Variables are substituted by prefixing them with $, eg.
58
59		echo Current device is $currdev
60
61	will print the current device.
62
63################################################################################
64# Tload DLoad a kernel or module
65
66	load [-t <type>] <filename>
67
68	Loads the module contained in <filename> into memory.  If no other
69	modules are loaded, <filename> must be a kernel or the command will
70	fail.
71
72	If -t is specified, the module is loaded as raw data of <type>, for
73	later use by the kernel or other modules.  <type> may be any string.
74
75################################################################################
76# Tls DList files
77
78	ls [-l] [<path>]
79
80	Displays a listing of files in the directory <path>, or the root
81	directory of the current device if <path> is not specified.
82
83	The -l argument displays file sizes as well; the process of obtaining
84	file sizes on some media may be very slow.
85
86################################################################################
87# Tlsdev DList devices
88
89	lsdev [-v]
90
91	List all of the devices from which it may be possible to load modules.
92	If -v is specified, print more details.
93
94################################################################################
95# Tlsmod DList modules
96
97	lsmod [-v]
98
99	List loaded modules. If [-v] is specified, print more details.
100
101################################################################################
102# Tmap-vdisk DMap virtual disk
103
104	map-vdisk filename
105
106	Map file as virtual disk.
107
108################################################################################
109# Tmore DPage files
110
111	more <filename> [<filename> ...]
112
113	Show contents of text files. When displaying the contents of more,
114	than one file, if the user elects to quit displaying a file, the
115	remaining files will not be shown.
116
117################################################################################
118# Tpnpscan DScan for PnP devices
119
120	pnpscan [-v]
121
122	Scan for Plug-and-Play devices.  This command is normally automatically
123	run as part of the boot process, in order to dynamically load modules
124	required for system operation.
125
126	If the -v argument is specified, details on the devices found will
127	be printed.
128
129################################################################################
130# Tset DSet a variable
131
132	set <variable name>
133	set <variable name>=<value>
134
135	The set command is used to set variables.
136
137################################################################################
138# Tset Sautoboot_delay DSet the default autoboot delay
139
140	set autoboot_delay=<value>
141
142	Sets the default delay for the autoboot command to <value> seconds.
143	Set value to -1 if you don't want to allow user to interrupt autoboot
144	process and escape to the loader prompt.
145
146################################################################################
147# Tset Sbootfile DSet the default boot file set
148
149	set bootfile=<filename>[;<filename>...]
150
151	Sets the default set of kernel boot filename(s). It may be overridden
152	by setting the bootfile variable to a semicolon-separated list of
153	filenames, each of which will be searched for in the module_path
154	directories. The default bootfile set is "kernel".
155
156################################################################################
157# Tset Sboot_askname DPrompt for root device
158
159	set boot_askname
160
161	Instructs the kernel to prompt the user for the name of the root device
162	when the kernel is booted.
163
164################################################################################
165# Tset Sboot_cdrom DMount root file system from CD-ROM
166
167	set boot_cdrom
168
169	Instructs the kernel to try to mount the root file system from CD-ROM.
170
171################################################################################
172# Tset Sboot_ddb DDrop to the kernel debugger (DDB)
173
174	set boot_ddb
175
176	Instructs the kernel to start in the DDB debugger, rather than
177	proceeding to initialize when booted.
178
179################################################################################
180# Tset Sboot_dfltroot DUse default root file system
181
182	set boot_dfltroot
183
184	Instructs the kernel to mount the statically compiled-in root
185	file system.
186
187################################################################################
188# Tset Sboot_gdb DSelect gdb-remote mode for the kernel debugger
189
190	set boot_gdb
191
192	Selects gdb-remote mode for the kernel debugger by default.
193
194################################################################################
195# Tset Sboot_multicons DUse multiple consoles
196
197	set boot_multicons
198
199	Enables multiple console support in the kernel early on boot.
200	In a running system, console configuration can be manipulated
201	by the conscontrol(8) utility.
202
203################################################################################
204# Tset Sboot_mute DMute the console
205
206	set boot_mute
207
208	All console output is suppressed when console is muted.
209	In a running system, the state of console muting can be
210	manipulated by the conscontrol(8) utility.
211
212################################################################################
213# Tset Sboot_pause DPause after each line during device probing
214
215	set boot_pause
216
217	During the device probe, pause after each line is printed.
218
219################################################################################
220# Tset Sboot_serial DUse serial console
221
222	set boot_serial
223
224	Force the use of a serial console even when an internal console
225	is present.
226
227################################################################################
228# Tset Sboot_single DStart system in single-user mode
229
230	set boot_single
231
232	Prevents the kernel from initiating a multi-user startup; instead,
233	a single-user mode will be entered when the kernel has finished
234	device probes.
235
236################################################################################
237# Tset Sboot_verbose DVerbose boot messages
238
239	set boot_verbose
240
241	Setting this variable causes extra debugging information to be printed
242	by the kernel during the boot phase.
243
244################################################################################
245# Tset Sconsole DSet the current console
246
247	set console[=<value>]
248
249	Sets the current console.  If <value> is omitted, a list of valid
250	consoles will be displayed.
251
252################################################################################
253# Tset Scurrdev DSet the current device
254
255	set currdev=<device>
256
257	Selects the default device.  See lsdev for available devices.
258
259################################################################################
260# Tset Sinit_path DSet the list of init candidates
261
262	set init_path=<path>[:<path>...]
263
264	Sets the list of binaries which the kernel will try to run as initial
265	process.
266
267
268################################################################################
269# Tset Smodule_path DSet the module search path
270
271	set module_path=<path>[;<path>...]
272
273	Sets the list of directories which will be searched in for modules
274	named in a load command or implicitly required by a dependency. The
275	default module_path is "/boot/modules" with the kernel directory
276	prepended.
277
278################################################################################
279# Tset Sprompt DSet the command prompt
280
281	set prompt=<value>
282
283	The command prompt is displayed when the loader is waiting for input.
284	Variable substitution is performed on the prompt.  The default
285	prompt can be set with:
286
287		set prompt=\${interpret}
288
289################################################################################
290# Tset Srootdev DSet the root filesystem
291
292	set rootdev=<path>
293
294	By default the value of $currdev is used to set the root filesystem
295	when the kernel is booted.  This can be overridden by setting
296	$rootdev explicitly.
297
298################################################################################
299# Tset Stunables DSet kernel tunable values
300
301	Various kernel tunable parameters can be overridden by specifying new
302	values in the environment.
303
304	set kern.ipc.nmbclusters=<value>
305
306		Set the number of mbuf clusters to be allocated.  The value
307		cannot be set below the default determined when the kernel
308		was compiled.
309
310	set kern.ipc.nsfbufs=<value>		NSFBUFS
311
312		Set the number of sendfile buffers to be allocated.  This
313		overrides the value determined when the kernel was compiled.
314
315	set vm.kmem_size=<value>		VM_KMEM_SIZE
316
317		Sets the size of kernel memory (bytes).  This overrides
318		the value determined when the kernel was compiled.
319
320	set machdep.disable_mtrrs=1
321
322		Disable the use of i686 MTRRs (i386 only)
323
324	set net.inet.tcp.tcbhashsize=<value>	TCBHASHSIZE
325
326		Overrides the compile-time set value of TCBHASHSIZE or
327		the preset default of 512.  Must be a power of 2.
328
329	hw.syscons.sc_no_suspend_vtswitch=<value>
330
331		Disable VT switching on suspend.
332
333		value is 0 (default) or non-zero to enable.
334
335	set hw.physmem=<value>			MAXMEM (i386 only)
336
337		Limits the amount of physical memory space available to
338		the system to <value> bytes.  <value> may have a k, M or G
339		suffix to indicate kilobytes, megabytes and gigabytes
340		respectively.  Note that the current i386 architecture
341		limits this value to 4GB.
342
343		On systems where memory cannot be accurately probed,
344		this option provides a hint as to the actual size of
345		system memory (which will be tested before use).
346
347	set hw.{acpi,pci}.host_start_mem=<value>
348
349		Sets the lowest address that the pci code will assign
350		when it doesn't have other information about the address
351		to assign (like from a pci bridge).  This is only useful
352		in older systems without a pci bridge.  Also, it only
353		impacts devices that the BIOS doesn't assign to, typically
354		CardBus bridges.  The default <value> is 0x80000000, but
355		some systems need values like 0xf0000000, 0xfc000000 or
356		0xfe000000 may be suitable for older systems (the older
357		the system, the higher the number typically should be).
358
359	set hw.pci.enable_io_modes=<value>
360
361		Enable PCI resources which are left off by some BIOSes
362		or are not enabled correctly by the device driver.
363
364		value is 1 (default), but this may cause problems with
365		some peripherals.  Set to 0 to disable.
366
367################################################################################
368# Tshow DShow the values of variables
369
370	show [<variable>]
371
372	Displays the value of <variable>, or all variables if not specified.
373	Multiple paths can be separated with a semicolon.
374
375################################################################################
376# Tinclude DRead commands from a script file
377
378	include <filename> [<filename> ...]
379
380	The entire contents of <filename> are read into memory before executing
381	commands, so it is safe to source a file from removable media.
382
383################################################################################
384# Tread DRead input from the terminal
385
386	read [-t <value>] [-p <prompt>] [<variable name>]
387
388	The read command reads a line of input from the terminal.  If the
389	-t argument is specified, it will return nothing if no input has been
390	received after <value> seconds.  (Any keypress will cancel the
391	timeout).
392
393	If -p is specified, <prompt> is printed before reading input. No
394	newline is emitted after the prompt.
395
396	If a variable name is supplied, the variable is set to the value read,
397	less any terminating newline.
398
399################################################################################
400# Tunload DRemove all modules from memory
401
402	unload
403
404	This command removes any kernel and all loaded modules from memory.
405
406################################################################################
407# Tunmap-vdisk DUnmap virtual disk
408
409	unmap-vdisk diskname
410
411	Delete virtual disk mapping.
412
413################################################################################
414# Tunset DUnset a variable
415
416	unset <variable name>
417
418	If allowed, the named variable's value is discarded and the variable
419	is removed.
420
421################################################################################
422