cmd: Fix potential NULL pointer dereference
[qemu.git] / qemu-options.hx
blob681eaf198ea2e8eec9489123fd281e2a9535d531
1 HXCOMM Use DEFHEADING() to define headings in both help text and texi
2 HXCOMM Text between STEXI and ETEXI are copied to texi version and
3 HXCOMM discarded from C version
4 HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to
5 HXCOMM construct option structures, enums and help message for specified
6 HXCOMM architectures.
7 HXCOMM HXCOMM can be used for comments, discarded from both texi and C
9 DEFHEADING(Standard options:)
10 STEXI
11 @table @option
12 ETEXI
14 DEF("help", 0, QEMU_OPTION_h,
15 "-h or -help display this help and exit\n", QEMU_ARCH_ALL)
16 STEXI
17 @item -h
18 @findex -h
19 Display help and exit
20 ETEXI
22 DEF("version", 0, QEMU_OPTION_version,
23 "-version display version information and exit\n", QEMU_ARCH_ALL)
24 STEXI
25 @item -version
26 @findex -version
27 Display version information and exit
28 ETEXI
30 DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
31 "-machine [type=]name[,prop[=value][,...]]\n"
32 " selects emulated machine (-machine ? for list)\n"
33 " property accel=accel1[:accel2[:...]] selects accelerator\n"
34 " supported accelerators are kvm, xen, tcg (default: tcg)\n",
35 QEMU_ARCH_ALL)
36 STEXI
37 @item -machine [type=]@var{name}[,prop=@var{value}[,...]]
38 @findex -machine
39 Select the emulated machine by @var{name}. Use @code{-machine ?} to list
40 available machines. Supported machine properties are:
41 @table @option
42 @item accel=@var{accels1}[:@var{accels2}[:...]]
43 This is used to enable an accelerator. Depending on the target architecture,
44 kvm, xen, or tcg can be available. By default, tcg is used. If there is more
45 than one accelerator specified, the next one is used if the previous one fails
46 to initialize.
47 @end table
48 ETEXI
50 HXCOMM Deprecated by -machine
51 DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL)
53 DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
54 "-cpu cpu select CPU (-cpu ? for list)\n", QEMU_ARCH_ALL)
55 STEXI
56 @item -cpu @var{model}
57 @findex -cpu
58 Select CPU model (-cpu ? for list and additional feature selection)
59 ETEXI
61 DEF("smp", HAS_ARG, QEMU_OPTION_smp,
62 "-smp n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
63 " set the number of CPUs to 'n' [default=1]\n"
64 " maxcpus= maximum number of total cpus, including\n"
65 " offline CPUs for hotplug, etc\n"
66 " cores= number of CPU cores on one socket\n"
67 " threads= number of threads on one CPU core\n"
68 " sockets= number of discrete sockets in the system\n",
69 QEMU_ARCH_ALL)
70 STEXI
71 @item -smp @var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
72 @findex -smp
73 Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
74 CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
75 to 4.
76 For the PC target, the number of @var{cores} per socket, the number
77 of @var{threads} per cores and the total number of @var{sockets} can be
78 specified. Missing values will be computed. If any on the three values is
79 given, the total number of CPUs @var{n} can be omitted. @var{maxcpus}
80 specifies the maximum number of hotpluggable CPUs.
81 ETEXI
83 DEF("numa", HAS_ARG, QEMU_OPTION_numa,
84 "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL)
85 STEXI
86 @item -numa @var{opts}
87 @findex -numa
88 Simulate a multi node NUMA system. If mem and cpus are omitted, resources
89 are split equally.
90 ETEXI
92 DEF("fda", HAS_ARG, QEMU_OPTION_fda,
93 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
94 DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
95 STEXI
96 @item -fda @var{file}
97 @item -fdb @var{file}
98 @findex -fda
99 @findex -fdb
100 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can
101 use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}).
102 ETEXI
104 DEF("hda", HAS_ARG, QEMU_OPTION_hda,
105 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
106 DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
107 DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
108 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
109 DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
110 STEXI
111 @item -hda @var{file}
112 @item -hdb @var{file}
113 @item -hdc @var{file}
114 @item -hdd @var{file}
115 @findex -hda
116 @findex -hdb
117 @findex -hdc
118 @findex -hdd
119 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
120 ETEXI
122 DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
123 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
124 QEMU_ARCH_ALL)
125 STEXI
126 @item -cdrom @var{file}
127 @findex -cdrom
128 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
129 @option{-cdrom} at the same time). You can use the host CD-ROM by
130 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
131 ETEXI
133 DEF("drive", HAS_ARG, QEMU_OPTION_drive,
134 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
135 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
136 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
137 " [,serial=s][,addr=A][,id=name][,aio=threads|native]\n"
138 " [,readonly=on|off]\n"
139 " use 'file' as a drive image\n", QEMU_ARCH_ALL)
140 STEXI
141 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
142 @findex -drive
144 Define a new drive. Valid options are:
146 @table @option
147 @item file=@var{file}
148 This option defines which disk image (@pxref{disk_images}) to use with
149 this drive. If the filename contains comma, you must double it
150 (for instance, "file=my,,file" to use file "my,file").
152 Special files such as iSCSI devices can be specified using protocol
153 specific URLs. See the section for "Device URL Syntax" for more information.
154 @item if=@var{interface}
155 This option defines on which type on interface the drive is connected.
156 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio.
157 @item bus=@var{bus},unit=@var{unit}
158 These options define where is connected the drive by defining the bus number and
159 the unit id.
160 @item index=@var{index}
161 This option defines where is connected the drive by using an index in the list
162 of available connectors of a given interface type.
163 @item media=@var{media}
164 This option defines the type of the media: disk or cdrom.
165 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
166 These options have the same definition as they have in @option{-hdachs}.
167 @item snapshot=@var{snapshot}
168 @var{snapshot} is "on" or "off" and allows to enable snapshot for given drive (see @option{-snapshot}).
169 @item cache=@var{cache}
170 @var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data.
171 @item aio=@var{aio}
172 @var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
173 @item format=@var{format}
174 Specify which disk @var{format} will be used rather than detecting
175 the format. Can be used to specifiy format=raw to avoid interpreting
176 an untrusted format header.
177 @item serial=@var{serial}
178 This option specifies the serial number to assign to the device.
179 @item addr=@var{addr}
180 Specify the controller's PCI address (if=virtio only).
181 @item werror=@var{action},rerror=@var{action}
182 Specify which @var{action} to take on write and read errors. Valid actions are:
183 "ignore" (ignore the error and try to continue), "stop" (pause QEMU),
184 "report" (report the error to the guest), "enospc" (pause QEMU only if the
185 host disk is full; report the error to the guest otherwise).
186 The default setting is @option{werror=enospc} and @option{rerror=report}.
187 @item readonly
188 Open drive @option{file} as read-only. Guest write attempts will fail.
189 @end table
191 By default, writethrough caching is used for all block device. This means that
192 the host page cache will be used to read and write data but write notification
193 will be sent to the guest only when the data has been reported as written by
194 the storage subsystem.
196 Writeback caching will report data writes as completed as soon as the data is
197 present in the host page cache. This is safe as long as you trust your host.
198 If your host crashes or loses power, then the guest may experience data
199 corruption.
201 The host page cache can be avoided entirely with @option{cache=none}. This will
202 attempt to do disk IO directly to the guests memory. QEMU may still perform
203 an internal copy of the data.
205 The host page cache can be avoided while only sending write notifications to
206 the guest when the data has been reported as written by the storage subsystem
207 using @option{cache=directsync}.
209 Some block drivers perform badly with @option{cache=writethrough}, most notably,
210 qcow2. If performance is more important than correctness,
211 @option{cache=writeback} should be used with qcow2.
213 In case you don't care about data integrity over host failures, use
214 cache=unsafe. This option tells qemu that it never needs to write any data
215 to the disk but can instead keeps things in cache. If anything goes wrong,
216 like your host losing power, the disk storage getting disconnected accidently,
217 etc. you're image will most probably be rendered unusable. When using
218 the @option{-snapshot} option, unsafe caching is always used.
220 Instead of @option{-cdrom} you can use:
221 @example
222 qemu -drive file=file,index=2,media=cdrom
223 @end example
225 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
226 use:
227 @example
228 qemu -drive file=file,index=0,media=disk
229 qemu -drive file=file,index=1,media=disk
230 qemu -drive file=file,index=2,media=disk
231 qemu -drive file=file,index=3,media=disk
232 @end example
234 You can connect a CDROM to the slave of ide0:
235 @example
236 qemu -drive file=file,if=ide,index=1,media=cdrom
237 @end example
239 If you don't specify the "file=" argument, you define an empty drive:
240 @example
241 qemu -drive if=ide,index=1,media=cdrom
242 @end example
244 You can connect a SCSI disk with unit ID 6 on the bus #0:
245 @example
246 qemu -drive file=file,if=scsi,bus=0,unit=6
247 @end example
249 Instead of @option{-fda}, @option{-fdb}, you can use:
250 @example
251 qemu -drive file=file,index=0,if=floppy
252 qemu -drive file=file,index=1,if=floppy
253 @end example
255 By default, @var{interface} is "ide" and @var{index} is automatically
256 incremented:
257 @example
258 qemu -drive file=a -drive file=b"
259 @end example
260 is interpreted like:
261 @example
262 qemu -hda a -hdb b
263 @end example
264 ETEXI
266 DEF("set", HAS_ARG, QEMU_OPTION_set,
267 "-set group.id.arg=value\n"
268 " set <arg> parameter for item <id> of type <group>\n"
269 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL)
270 STEXI
271 @item -set
272 @findex -set
273 TODO
274 ETEXI
276 DEF("global", HAS_ARG, QEMU_OPTION_global,
277 "-global driver.property=value\n"
278 " set a global default for a driver property\n",
279 QEMU_ARCH_ALL)
280 STEXI
281 @item -global
282 @findex -global
283 TODO
284 ETEXI
286 DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
287 "-mtdblock file use 'file' as on-board Flash memory image\n",
288 QEMU_ARCH_ALL)
289 STEXI
290 @item -mtdblock @var{file}
291 @findex -mtdblock
292 Use @var{file} as on-board Flash memory image.
293 ETEXI
295 DEF("sd", HAS_ARG, QEMU_OPTION_sd,
296 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL)
297 STEXI
298 @item -sd @var{file}
299 @findex -sd
300 Use @var{file} as SecureDigital card image.
301 ETEXI
303 DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
304 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL)
305 STEXI
306 @item -pflash @var{file}
307 @findex -pflash
308 Use @var{file} as a parallel flash image.
309 ETEXI
311 DEF("boot", HAS_ARG, QEMU_OPTION_boot,
312 "-boot [order=drives][,once=drives][,menu=on|off]\n"
313 " [,splash=sp_name][,splash-time=sp_time]\n"
314 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
315 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n"
316 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n",
317 QEMU_ARCH_ALL)
318 STEXI
319 @item -boot [order=@var{drives}][,once=@var{drives}][,menu=on|off][,splash=@var{sp_name}][,splash-time=@var{sp_time}]
320 @findex -boot
321 Specify boot order @var{drives} as a string of drive letters. Valid
322 drive letters depend on the target achitecture. The x86 PC uses: a, b
323 (floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
324 from network adapter 1-4), hard disk boot is the default. To apply a
325 particular boot order only on the first startup, specify it via
326 @option{once}.
328 Interactive boot menus/prompts can be enabled via @option{menu=on} as far
329 as firmware/BIOS supports them. The default is non-interactive boot.
331 A splash picture could be passed to bios, enabling user to show it as logo,
332 when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
333 supports them. Currently Seabios for X86 system support it.
334 limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
335 format(true color). The resolution should be supported by the SVGA mode, so
336 the recommended is 320x240, 640x480, 800x640.
338 @example
339 # try to boot from network first, then from hard disk
340 qemu -boot order=nc
341 # boot from CD-ROM first, switch back to default order after reboot
342 qemu -boot once=d
343 # boot with a splash picture for 5 seconds.
344 qemu -boot menu=on,splash=/root/boot.bmp,splash-time=5000
345 @end example
347 Note: The legacy format '-boot @var{drives}' is still supported but its
348 use is discouraged as it may be removed from future versions.
349 ETEXI
351 DEF("snapshot", 0, QEMU_OPTION_snapshot,
352 "-snapshot write to temporary files instead of disk image files\n",
353 QEMU_ARCH_ALL)
354 STEXI
355 @item -snapshot
356 @findex -snapshot
357 Write to temporary files instead of disk image files. In this case,
358 the raw disk image you use is not written back. You can however force
359 the write back by pressing @key{C-a s} (@pxref{disk_images}).
360 ETEXI
362 DEF("m", HAS_ARG, QEMU_OPTION_m,
363 "-m megs set virtual RAM size to megs MB [default="
364 stringify(DEFAULT_RAM_SIZE) "]\n", QEMU_ARCH_ALL)
365 STEXI
366 @item -m @var{megs}
367 @findex -m
368 Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally,
369 a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or
370 gigabytes respectively.
371 ETEXI
373 DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
374 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
375 STEXI
376 @item -mem-path @var{path}
377 Allocate guest RAM from a temporarily created file in @var{path}.
378 ETEXI
380 #ifdef MAP_POPULATE
381 DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
382 "-mem-prealloc preallocate guest memory (use with -mem-path)\n",
383 QEMU_ARCH_ALL)
384 STEXI
385 @item -mem-prealloc
386 Preallocate memory when using -mem-path.
387 ETEXI
388 #endif
390 DEF("k", HAS_ARG, QEMU_OPTION_k,
391 "-k language use keyboard layout (for example 'fr' for French)\n",
392 QEMU_ARCH_ALL)
393 STEXI
394 @item -k @var{language}
395 @findex -k
396 Use keyboard layout @var{language} (for example @code{fr} for
397 French). This option is only needed where it is not easy to get raw PC
398 keycodes (e.g. on Macs, with some X11 servers or with a VNC
399 display). You don't normally need to use it on PC/Linux or PC/Windows
400 hosts.
402 The available layouts are:
403 @example
404 ar de-ch es fo fr-ca hu ja mk no pt-br sv
405 da en-gb et fr fr-ch is lt nl pl ru th
406 de en-us fi fr-be hr it lv nl-be pt sl tr
407 @end example
409 The default is @code{en-us}.
410 ETEXI
413 DEF("audio-help", 0, QEMU_OPTION_audio_help,
414 "-audio-help print list of audio drivers and their options\n",
415 QEMU_ARCH_ALL)
416 STEXI
417 @item -audio-help
418 @findex -audio-help
419 Will show the audio subsystem help: list of drivers, tunable
420 parameters.
421 ETEXI
423 DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
424 "-soundhw c1,... enable audio support\n"
425 " and only specified sound cards (comma separated list)\n"
426 " use -soundhw ? to get the list of supported cards\n"
427 " use -soundhw all to enable all of them\n", QEMU_ARCH_ALL)
428 STEXI
429 @item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
430 @findex -soundhw
431 Enable audio and selected sound hardware. Use ? to print all
432 available sound hardware.
434 @example
435 qemu -soundhw sb16,adlib disk.img
436 qemu -soundhw es1370 disk.img
437 qemu -soundhw ac97 disk.img
438 qemu -soundhw hda disk.img
439 qemu -soundhw all disk.img
440 qemu -soundhw ?
441 @end example
443 Note that Linux's i810_audio OSS kernel (for AC97) module might
444 require manually specifying clocking.
446 @example
447 modprobe i810_audio clocking=48000
448 @end example
449 ETEXI
451 STEXI
452 @end table
453 ETEXI
455 DEF("usb", 0, QEMU_OPTION_usb,
456 "-usb enable the USB driver (will be the default soon)\n",
457 QEMU_ARCH_ALL)
458 STEXI
459 USB options:
460 @table @option
462 @item -usb
463 @findex -usb
464 Enable the USB driver (will be the default soon)
465 ETEXI
467 DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
468 "-usbdevice name add the host or guest USB device 'name'\n",
469 QEMU_ARCH_ALL)
470 STEXI
472 @item -usbdevice @var{devname}
473 @findex -usbdevice
474 Add the USB device @var{devname}. @xref{usb_devices}.
476 @table @option
478 @item mouse
479 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
481 @item tablet
482 Pointer device that uses absolute coordinates (like a touchscreen). This
483 means qemu is able to report the mouse position without having to grab the
484 mouse. Also overrides the PS/2 mouse emulation when activated.
486 @item disk:[format=@var{format}]:@var{file}
487 Mass storage device based on file. The optional @var{format} argument
488 will be used rather than detecting the format. Can be used to specifiy
489 @code{format=raw} to avoid interpreting an untrusted format header.
491 @item host:@var{bus}.@var{addr}
492 Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
494 @item host:@var{vendor_id}:@var{product_id}
495 Pass through the host device identified by @var{vendor_id}:@var{product_id}
496 (Linux only).
498 @item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
499 Serial converter to host character device @var{dev}, see @code{-serial} for the
500 available devices.
502 @item braille
503 Braille device. This will use BrlAPI to display the braille output on a real
504 or fake device.
506 @item net:@var{options}
507 Network adapter that supports CDC ethernet and RNDIS protocols.
509 @end table
510 ETEXI
512 DEF("device", HAS_ARG, QEMU_OPTION_device,
513 "-device driver[,prop[=value][,...]]\n"
514 " add device (based on driver)\n"
515 " prop=value,... sets driver properties\n"
516 " use -device ? to print all possible drivers\n"
517 " use -device driver,? to print all possible properties\n",
518 QEMU_ARCH_ALL)
519 STEXI
520 @item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
521 @findex -device
522 Add device @var{driver}. @var{prop}=@var{value} sets driver
523 properties. Valid properties depend on the driver. To get help on
524 possible drivers and properties, use @code{-device ?} and
525 @code{-device @var{driver},?}.
526 ETEXI
528 DEFHEADING()
530 DEFHEADING(File system options:)
532 DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
533 "-fsdev fsdriver,id=id,path=path,[security_model={mapped|passthrough|none}]\n"
534 " [,writeout=immediate][,readonly]\n",
535 QEMU_ARCH_ALL)
537 STEXI
539 @item -fsdev @var{fsdriver},id=@var{id},path=@var{path},[security_model=@var{security_model}][,writeout=@var{writeout}][,readonly]
540 @findex -fsdev
541 Define a new file system device. Valid options are:
542 @table @option
543 @item @var{fsdriver}
544 This option specifies the fs driver backend to use.
545 Currently "local" and "handle" file system drivers are supported.
546 @item id=@var{id}
547 Specifies identifier for this device
548 @item path=@var{path}
549 Specifies the export path for the file system device. Files under
550 this path will be available to the 9p client on the guest.
551 @item security_model=@var{security_model}
552 Specifies the security model to be used for this export path.
553 Supported security models are "passthrough", "mapped" and "none".
554 In "passthrough" security model, files are stored using the same
555 credentials as they are created on the guest. This requires qemu
556 to run as root. In "mapped" security model, some of the file
557 attributes like uid, gid, mode bits and link target are stored as
558 file attributes. Directories exported by this security model cannot
559 interact with other unix tools. "none" security model is same as
560 passthrough except the sever won't report failures if it fails to
561 set file attributes like ownership. Security model is mandatory
562 only for local fsdriver. Other fsdrivers (like handle) don't take
563 security model as a parameter.
564 @item writeout=@var{writeout}
565 This is an optional argument. The only supported value is "immediate".
566 This means that host page cache will be used to read and write data but
567 write notification will be sent to the guest only when the data has been
568 reported as written by the storage subsystem.
569 @item readonly
570 Enables exporting 9p share as a readonly mount for guests. By default
571 read-write access is given.
572 @end table
574 -fsdev option is used along with -device driver "virtio-9p-pci".
575 @item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
576 Options for virtio-9p-pci driver are:
577 @table @option
578 @item fsdev=@var{id}
579 Specifies the id value specified along with -fsdev option
580 @item mount_tag=@var{mount_tag}
581 Specifies the tag name to be used by the guest to mount this export point
582 @end table
584 ETEXI
586 DEFHEADING()
588 DEFHEADING(Virtual File system pass-through options:)
590 DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
591 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped|passthrough|none]\n"
592 " [,writeout=immediate][,readonly]\n",
593 QEMU_ARCH_ALL)
595 STEXI
597 @item -virtfs @var{fsdriver},path=@var{path},mount_tag=@var{mount_tag},security_model=@var{security_model}[,writeout=@var{writeout}][,readonly]
598 @findex -virtfs
600 The general form of a Virtual File system pass-through options are:
601 @table @option
602 @item @var{fsdriver}
603 This option specifies the fs driver backend to use.
604 Currently "local" and "handle" file system drivers are supported.
605 @item id=@var{id}
606 Specifies identifier for this device
607 @item path=@var{path}
608 Specifies the export path for the file system device. Files under
609 this path will be available to the 9p client on the guest.
610 @item security_model=@var{security_model}
611 Specifies the security model to be used for this export path.
612 Supported security models are "passthrough", "mapped" and "none".
613 In "passthrough" security model, files are stored using the same
614 credentials as they are created on the guest. This requires qemu
615 to run as root. In "mapped" security model, some of the file
616 attributes like uid, gid, mode bits and link target are stored as
617 file attributes. Directories exported by this security model cannot
618 interact with other unix tools. "none" security model is same as
619 passthrough except the sever won't report failures if it fails to
620 set file attributes like ownership. Security model is mandatory only
621 for local fsdriver. Other fsdrivers (like handle) don't take security
622 model as a parameter.
623 @item writeout=@var{writeout}
624 This is an optional argument. The only supported value is "immediate".
625 This means that host page cache will be used to read and write data but
626 write notification will be sent to the guest only when the data has been
627 reported as written by the storage subsystem.
628 @item readonly
629 Enables exporting 9p share as a readonly mount for guests. By default
630 read-write access is given.
631 @end table
632 ETEXI
634 DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
635 "-virtfs_synth Create synthetic file system image\n",
636 QEMU_ARCH_ALL)
637 STEXI
638 @item -virtfs_synth
639 @findex -virtfs_synth
640 Create synthetic file system image
641 ETEXI
643 DEFHEADING()
645 DEF("name", HAS_ARG, QEMU_OPTION_name,
646 "-name string1[,process=string2]\n"
647 " set the name of the guest\n"
648 " string1 sets the window title and string2 the process name (on Linux)\n",
649 QEMU_ARCH_ALL)
650 STEXI
651 @item -name @var{name}
652 @findex -name
653 Sets the @var{name} of the guest.
654 This name will be displayed in the SDL window caption.
655 The @var{name} will also be used for the VNC server.
656 Also optionally set the top visible process name in Linux.
657 ETEXI
659 DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
660 "-uuid %08x-%04x-%04x-%04x-%012x\n"
661 " specify machine UUID\n", QEMU_ARCH_ALL)
662 STEXI
663 @item -uuid @var{uuid}
664 @findex -uuid
665 Set system UUID.
666 ETEXI
668 STEXI
669 @end table
670 ETEXI
672 DEFHEADING()
674 DEFHEADING(Display options:)
676 STEXI
677 @table @option
678 ETEXI
680 DEF("display", HAS_ARG, QEMU_OPTION_display,
681 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
682 " [,window_close=on|off]|curses|none|\n"
683 " vnc=<display>[,<optargs>]\n"
684 " select display type\n", QEMU_ARCH_ALL)
685 STEXI
686 @item -display @var{type}
687 @findex -display
688 Select type of display to use. This option is a replacement for the
689 old style -sdl/-curses/... options. Valid values for @var{type} are
690 @table @option
691 @item sdl
692 Display video output via SDL (usually in a separate graphics
693 window; see the SDL documentation for other possibilities).
694 @item curses
695 Display video output via curses. For graphics device models which
696 support a text mode, QEMU can display this output using a
697 curses/ncurses interface. Nothing is displayed when the graphics
698 device is in graphical mode or if the graphics device does not support
699 a text mode. Generally only the VGA device models support text mode.
700 @item none
701 Do not display video output. The guest will still see an emulated
702 graphics card, but its output will not be displayed to the QEMU
703 user. This option differs from the -nographic option in that it
704 only affects what is done with video output; -nographic also changes
705 the destination of the serial and parallel port data.
706 @item vnc
707 Start a VNC server on display <arg>
708 @end table
709 ETEXI
711 DEF("nographic", 0, QEMU_OPTION_nographic,
712 "-nographic disable graphical output and redirect serial I/Os to console\n",
713 QEMU_ARCH_ALL)
714 STEXI
715 @item -nographic
716 @findex -nographic
717 Normally, QEMU uses SDL to display the VGA output. With this option,
718 you can totally disable graphical output so that QEMU is a simple
719 command line application. The emulated serial port is redirected on
720 the console. Therefore, you can still use QEMU to debug a Linux kernel
721 with a serial console.
722 ETEXI
724 DEF("curses", 0, QEMU_OPTION_curses,
725 "-curses use a curses/ncurses interface instead of SDL\n",
726 QEMU_ARCH_ALL)
727 STEXI
728 @item -curses
729 @findex curses
730 Normally, QEMU uses SDL to display the VGA output. With this option,
731 QEMU can display the VGA output when in text mode using a
732 curses/ncurses interface. Nothing is displayed in graphical mode.
733 ETEXI
735 DEF("no-frame", 0, QEMU_OPTION_no_frame,
736 "-no-frame open SDL window without a frame and window decorations\n",
737 QEMU_ARCH_ALL)
738 STEXI
739 @item -no-frame
740 @findex -no-frame
741 Do not use decorations for SDL windows and start them using the whole
742 available screen space. This makes the using QEMU in a dedicated desktop
743 workspace more convenient.
744 ETEXI
746 DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
747 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
748 QEMU_ARCH_ALL)
749 STEXI
750 @item -alt-grab
751 @findex -alt-grab
752 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
753 affects the special keys (for fullscreen, monitor-mode switching, etc).
754 ETEXI
756 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
757 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
758 QEMU_ARCH_ALL)
759 STEXI
760 @item -ctrl-grab
761 @findex -ctrl-grab
762 Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
763 affects the special keys (for fullscreen, monitor-mode switching, etc).
764 ETEXI
766 DEF("no-quit", 0, QEMU_OPTION_no_quit,
767 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL)
768 STEXI
769 @item -no-quit
770 @findex -no-quit
771 Disable SDL window close capability.
772 ETEXI
774 DEF("sdl", 0, QEMU_OPTION_sdl,
775 "-sdl enable SDL\n", QEMU_ARCH_ALL)
776 STEXI
777 @item -sdl
778 @findex -sdl
779 Enable SDL.
780 ETEXI
782 DEF("spice", HAS_ARG, QEMU_OPTION_spice,
783 "-spice <args> enable spice\n", QEMU_ARCH_ALL)
784 STEXI
785 @item -spice @var{option}[,@var{option}[,...]]
786 @findex -spice
787 Enable the spice remote desktop protocol. Valid options are
789 @table @option
791 @item port=<nr>
792 Set the TCP port spice is listening on for plaintext channels.
794 @item addr=<addr>
795 Set the IP address spice is listening on. Default is any address.
797 @item ipv4
798 @item ipv6
799 Force using the specified IP version.
801 @item password=<secret>
802 Set the password you need to authenticate.
804 @item sasl
805 Require that the client use SASL to authenticate with the spice.
806 The exact choice of authentication method used is controlled from the
807 system / user's SASL configuration file for the 'qemu' service. This
808 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
809 unprivileged user, an environment variable SASL_CONF_PATH can be used
810 to make it search alternate locations for the service config.
811 While some SASL auth methods can also provide data encryption (eg GSSAPI),
812 it is recommended that SASL always be combined with the 'tls' and
813 'x509' settings to enable use of SSL and server certificates. This
814 ensures a data encryption preventing compromise of authentication
815 credentials.
817 @item disable-ticketing
818 Allow client connects without authentication.
820 @item disable-copy-paste
821 Disable copy paste between the client and the guest.
823 @item tls-port=<nr>
824 Set the TCP port spice is listening on for encrypted channels.
826 @item x509-dir=<dir>
827 Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
829 @item x509-key-file=<file>
830 @item x509-key-password=<file>
831 @item x509-cert-file=<file>
832 @item x509-cacert-file=<file>
833 @item x509-dh-key-file=<file>
834 The x509 file names can also be configured individually.
836 @item tls-ciphers=<list>
837 Specify which ciphers to use.
839 @item tls-channel=[main|display|inputs|record|playback|tunnel]
840 @item plaintext-channel=[main|display|inputs|record|playback|tunnel]
841 Force specific channel to be used with or without TLS encryption. The
842 options can be specified multiple times to configure multiple
843 channels. The special name "default" can be used to set the default
844 mode. For channels which are not explicitly forced into one mode the
845 spice client is allowed to pick tls/plaintext as he pleases.
847 @item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
848 Configure image compression (lossless).
849 Default is auto_glz.
851 @item jpeg-wan-compression=[auto|never|always]
852 @item zlib-glz-wan-compression=[auto|never|always]
853 Configure wan image compression (lossy for slow links).
854 Default is auto.
856 @item streaming-video=[off|all|filter]
857 Configure video stream detection. Default is filter.
859 @item agent-mouse=[on|off]
860 Enable/disable passing mouse events via vdagent. Default is on.
862 @item playback-compression=[on|off]
863 Enable/disable audio stream compression (using celt 0.5.1). Default is on.
865 @end table
866 ETEXI
868 DEF("portrait", 0, QEMU_OPTION_portrait,
869 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
870 QEMU_ARCH_ALL)
871 STEXI
872 @item -portrait
873 @findex -portrait
874 Rotate graphical output 90 deg left (only PXA LCD).
875 ETEXI
877 DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
878 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
879 QEMU_ARCH_ALL)
880 STEXI
881 @item -rotate
882 @findex -rotate
883 Rotate graphical output some deg left (only PXA LCD).
884 ETEXI
886 DEF("vga", HAS_ARG, QEMU_OPTION_vga,
887 "-vga [std|cirrus|vmware|qxl|xenfb|none]\n"
888 " select video card type\n", QEMU_ARCH_ALL)
889 STEXI
890 @item -vga @var{type}
891 @findex -vga
892 Select type of VGA card to emulate. Valid values for @var{type} are
893 @table @option
894 @item cirrus
895 Cirrus Logic GD5446 Video card. All Windows versions starting from
896 Windows 95 should recognize and use this graphic card. For optimal
897 performances, use 16 bit color depth in the guest and the host OS.
898 (This one is the default)
899 @item std
900 Standard VGA card with Bochs VBE extensions. If your guest OS
901 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
902 to use high resolution modes (>= 1280x1024x16) then you should use
903 this option.
904 @item vmware
905 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
906 recent XFree86/XOrg server or Windows guest with a driver for this
907 card.
908 @item qxl
909 QXL paravirtual graphic card. It is VGA compatible (including VESA
910 2.0 VBE support). Works best with qxl guest drivers installed though.
911 Recommended choice when using the spice protocol.
912 @item none
913 Disable VGA card.
914 @end table
915 ETEXI
917 DEF("full-screen", 0, QEMU_OPTION_full_screen,
918 "-full-screen start in full screen\n", QEMU_ARCH_ALL)
919 STEXI
920 @item -full-screen
921 @findex -full-screen
922 Start in full screen.
923 ETEXI
925 DEF("g", 1, QEMU_OPTION_g ,
926 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
927 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
928 STEXI
929 @item -g @var{width}x@var{height}[x@var{depth}]
930 @findex -g
931 Set the initial graphical resolution and depth (PPC, SPARC only).
932 ETEXI
934 DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
935 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL)
936 STEXI
937 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
938 @findex -vnc
939 Normally, QEMU uses SDL to display the VGA output. With this option,
940 you can have QEMU listen on VNC display @var{display} and redirect the VGA
941 display over the VNC session. It is very useful to enable the usb
942 tablet device when using this option (option @option{-usbdevice
943 tablet}). When using the VNC display, you must use the @option{-k}
944 parameter to set the keyboard layout if you are not using en-us. Valid
945 syntax for the @var{display} is
947 @table @option
949 @item @var{host}:@var{d}
951 TCP connections will only be allowed from @var{host} on display @var{d}.
952 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
953 be omitted in which case the server will accept connections from any host.
955 @item unix:@var{path}
957 Connections will be allowed over UNIX domain sockets where @var{path} is the
958 location of a unix socket to listen for connections on.
960 @item none
962 VNC is initialized but not started. The monitor @code{change} command
963 can be used to later start the VNC server.
965 @end table
967 Following the @var{display} value there may be one or more @var{option} flags
968 separated by commas. Valid options are
970 @table @option
972 @item reverse
974 Connect to a listening VNC client via a ``reverse'' connection. The
975 client is specified by the @var{display}. For reverse network
976 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
977 is a TCP port number, not a display number.
979 @item password
981 Require that password based authentication is used for client connections.
982 The password must be set separately using the @code{change} command in the
983 @ref{pcsys_monitor}
985 @item tls
987 Require that client use TLS when communicating with the VNC server. This
988 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
989 attack. It is recommended that this option be combined with either the
990 @option{x509} or @option{x509verify} options.
992 @item x509=@var{/path/to/certificate/dir}
994 Valid if @option{tls} is specified. Require that x509 credentials are used
995 for negotiating the TLS session. The server will send its x509 certificate
996 to the client. It is recommended that a password be set on the VNC server
997 to provide authentication of the client when this is used. The path following
998 this option specifies where the x509 certificates are to be loaded from.
999 See the @ref{vnc_security} section for details on generating certificates.
1001 @item x509verify=@var{/path/to/certificate/dir}
1003 Valid if @option{tls} is specified. Require that x509 credentials are used
1004 for negotiating the TLS session. The server will send its x509 certificate
1005 to the client, and request that the client send its own x509 certificate.
1006 The server will validate the client's certificate against the CA certificate,
1007 and reject clients when validation fails. If the certificate authority is
1008 trusted, this is a sufficient authentication mechanism. You may still wish
1009 to set a password on the VNC server as a second authentication layer. The
1010 path following this option specifies where the x509 certificates are to
1011 be loaded from. See the @ref{vnc_security} section for details on generating
1012 certificates.
1014 @item sasl
1016 Require that the client use SASL to authenticate with the VNC server.
1017 The exact choice of authentication method used is controlled from the
1018 system / user's SASL configuration file for the 'qemu' service. This
1019 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1020 unprivileged user, an environment variable SASL_CONF_PATH can be used
1021 to make it search alternate locations for the service config.
1022 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1023 it is recommended that SASL always be combined with the 'tls' and
1024 'x509' settings to enable use of SSL and server certificates. This
1025 ensures a data encryption preventing compromise of authentication
1026 credentials. See the @ref{vnc_security} section for details on using
1027 SASL authentication.
1029 @item acl
1031 Turn on access control lists for checking of the x509 client certificate
1032 and SASL party. For x509 certs, the ACL check is made against the
1033 certificate's distinguished name. This is something that looks like
1034 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1035 made against the username, which depending on the SASL plugin, may
1036 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1037 When the @option{acl} flag is set, the initial access list will be
1038 empty, with a @code{deny} policy. Thus no one will be allowed to
1039 use the VNC server until the ACLs have been loaded. This can be
1040 achieved using the @code{acl} monitor command.
1042 @item lossy
1044 Enable lossy compression methods (gradient, JPEG, ...). If this
1045 option is set, VNC client may receive lossy framebuffer updates
1046 depending on its encoding settings. Enabling this option can save
1047 a lot of bandwidth at the expense of quality.
1049 @item non-adaptive
1051 Disable adaptive encodings. Adaptive encodings are enabled by default.
1052 An adaptive encoding will try to detect frequently updated screen regions,
1053 and send updates in these regions using a lossy encoding (like JPEG).
1054 This can be really helpful to save bandwidth when playing videos. Disabling
1055 adaptive encodings allows to restore the original static behavior of encodings
1056 like Tight.
1058 @end table
1059 ETEXI
1061 STEXI
1062 @end table
1063 ETEXI
1065 DEFHEADING()
1067 DEFHEADING(i386 target only:)
1068 STEXI
1069 @table @option
1070 ETEXI
1072 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1073 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1074 QEMU_ARCH_I386)
1075 STEXI
1076 @item -win2k-hack
1077 @findex -win2k-hack
1078 Use it when installing Windows 2000 to avoid a disk full bug. After
1079 Windows 2000 is installed, you no longer need this option (this option
1080 slows down the IDE transfers).
1081 ETEXI
1083 HXCOMM Deprecated by -rtc
1084 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1086 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1087 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1088 QEMU_ARCH_I386)
1089 STEXI
1090 @item -no-fd-bootchk
1091 @findex -no-fd-bootchk
1092 Disable boot signature checking for floppy disks in Bochs BIOS. It may
1093 be needed to boot from old floppy disks.
1094 TODO: check reference to Bochs BIOS.
1095 ETEXI
1097 DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1098 "-no-acpi disable ACPI\n", QEMU_ARCH_I386)
1099 STEXI
1100 @item -no-acpi
1101 @findex -no-acpi
1102 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1103 it if your guest OS complains about ACPI problems (PC target machine
1104 only).
1105 ETEXI
1107 DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1108 "-no-hpet disable HPET\n", QEMU_ARCH_I386)
1109 STEXI
1110 @item -no-hpet
1111 @findex -no-hpet
1112 Disable HPET support.
1113 ETEXI
1115 DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
1116 "-balloon none disable balloon device\n"
1117 "-balloon virtio[,addr=str]\n"
1118 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL)
1119 STEXI
1120 @item -balloon none
1121 @findex -balloon
1122 Disable balloon device.
1123 @item -balloon virtio[,addr=@var{addr}]
1124 Enable virtio balloon device (default), optionally with PCI address
1125 @var{addr}.
1126 ETEXI
1128 DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1129 "-acpitable [sig=str][,rev=n][,oem_id=str][,oem_table_id=str][,oem_rev=n][,asl_compiler_id=str][,asl_compiler_rev=n][,{data|file}=file1[:file2]...]\n"
1130 " ACPI table description\n", QEMU_ARCH_I386)
1131 STEXI
1132 @item -acpitable [sig=@var{str}][,rev=@var{n}][,oem_id=@var{str}][,oem_table_id=@var{str}][,oem_rev=@var{n}] [,asl_compiler_id=@var{str}][,asl_compiler_rev=@var{n}][,data=@var{file1}[:@var{file2}]...]
1133 @findex -acpitable
1134 Add ACPI table with specified header fields and context from specified files.
1135 For file=, take whole ACPI table from the specified files, including all
1136 ACPI headers (possible overridden by other options).
1137 For data=, only data
1138 portion of the table is used, all header information is specified in the
1139 command line.
1140 ETEXI
1142 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1143 "-smbios file=binary\n"
1144 " load SMBIOS entry from binary file\n"
1145 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1146 " specify SMBIOS type 0 fields\n"
1147 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1148 " [,uuid=uuid][,sku=str][,family=str]\n"
1149 " specify SMBIOS type 1 fields\n", QEMU_ARCH_I386)
1150 STEXI
1151 @item -smbios file=@var{binary}
1152 @findex -smbios
1153 Load SMBIOS entry from binary file.
1155 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}]
1156 @findex -smbios
1157 Specify SMBIOS type 0 fields
1159 @item -smbios type=1[,manufacturer=@var{str}][,product=@var{str}] [,version=@var{str}][,serial=@var{str}][,uuid=@var{uuid}][,sku=@var{str}] [,family=@var{str}]
1160 Specify SMBIOS type 1 fields
1161 ETEXI
1163 DEFHEADING()
1164 STEXI
1165 @end table
1166 ETEXI
1168 DEFHEADING(Network options:)
1169 STEXI
1170 @table @option
1171 ETEXI
1173 HXCOMM Legacy slirp options (now moved to -net user):
1174 #ifdef CONFIG_SLIRP
1175 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1176 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1177 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1178 #ifndef _WIN32
1179 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1180 #endif
1181 #endif
1183 DEF("net", HAS_ARG, QEMU_OPTION_net,
1184 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
1185 " create a new Network Interface Card and connect it to VLAN 'n'\n"
1186 #ifdef CONFIG_SLIRP
1187 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=on|off]\n"
1188 " [,hostname=host][,dhcpstart=addr][,dns=addr][,tftp=dir][,bootfile=f]\n"
1189 " [,hostfwd=rule][,guestfwd=rule]"
1190 #ifndef _WIN32
1191 "[,smb=dir[,smbserver=addr]]\n"
1192 #endif
1193 " connect the user mode network stack to VLAN 'n', configure its\n"
1194 " DHCP server and enabled optional services\n"
1195 #endif
1196 #ifdef _WIN32
1197 "-net tap[,vlan=n][,name=str],ifname=name\n"
1198 " connect the host TAP network interface to VLAN 'n'\n"
1199 #else
1200 "-net tap[,vlan=n][,name=str][,fd=h][,ifname=name][,script=file][,downscript=dfile][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off][,vhostfd=h][,vhostforce=on|off]\n"
1201 " connect the host TAP network interface to VLAN 'n' and use the\n"
1202 " network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1203 " and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1204 " use '[down]script=no' to disable script execution\n"
1205 " use 'fd=h' to connect to an already opened TAP interface\n"
1206 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
1207 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
1208 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1209 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1210 " use vhost=on to enable experimental in kernel accelerator\n"
1211 " (only has effect for virtio guests which use MSIX)\n"
1212 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1213 " use 'vhostfd=h' to connect to an already opened vhost net device\n"
1214 #endif
1215 "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n"
1216 " connect the vlan 'n' to another VLAN using a socket connection\n"
1217 "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1218 " connect the vlan 'n' to multicast maddr and port\n"
1219 " use 'localaddr=addr' to specify the host address to send packets from\n"
1220 #ifdef CONFIG_VDE
1221 "-net vde[,vlan=n][,name=str][,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1222 " connect the vlan 'n' to port 'n' of a vde switch running\n"
1223 " on host and listening for incoming connections on 'socketpath'.\n"
1224 " Use group 'groupname' and mode 'octalmode' to change default\n"
1225 " ownership and permissions for communication port.\n"
1226 #endif
1227 "-net dump[,vlan=n][,file=f][,len=n]\n"
1228 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n"
1229 "-net none use it alone to have zero network devices. If no -net option\n"
1230 " is provided, the default is '-net nic -net user'\n", QEMU_ARCH_ALL)
1231 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1232 "-netdev ["
1233 #ifdef CONFIG_SLIRP
1234 "user|"
1235 #endif
1236 "tap|"
1237 #ifdef CONFIG_VDE
1238 "vde|"
1239 #endif
1240 "socket],id=str[,option][,option][,...]\n", QEMU_ARCH_ALL)
1241 STEXI
1242 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1243 @findex -net
1244 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1245 = 0 is the default). The NIC is an e1000 by default on the PC
1246 target. Optionally, the MAC address can be changed to @var{mac}, the
1247 device address set to @var{addr} (PCI cards only),
1248 and a @var{name} can be assigned for use in monitor commands.
1249 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1250 that the card should have; this option currently only affects virtio cards; set
1251 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1252 NIC is created. Qemu can emulate several different models of network card.
1253 Valid values for @var{type} are
1254 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1255 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1256 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1257 Not all devices are supported on all targets. Use -net nic,model=?
1258 for a list of available devices for your target.
1260 @item -net user[,@var{option}][,@var{option}][,...]
1261 Use the user mode network stack which requires no administrator
1262 privilege to run. Valid options are:
1264 @table @option
1265 @item vlan=@var{n}
1266 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1268 @item name=@var{name}
1269 Assign symbolic name for use in monitor commands.
1271 @item net=@var{addr}[/@var{mask}]
1272 Set IP network address the guest will see. Optionally specify the netmask,
1273 either in the form a.b.c.d or as number of valid top-most bits. Default is
1274 10.0.2.0/24.
1276 @item host=@var{addr}
1277 Specify the guest-visible address of the host. Default is the 2nd IP in the
1278 guest network, i.e. x.x.x.2.
1280 @item restrict=on|off
1281 If this option is enabled, the guest will be isolated, i.e. it will not be
1282 able to contact the host and no guest IP packets will be routed over the host
1283 to the outside. This option does not affect any explicitly set forwarding rules.
1285 @item hostname=@var{name}
1286 Specifies the client hostname reported by the builtin DHCP server.
1288 @item dhcpstart=@var{addr}
1289 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1290 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1292 @item dns=@var{addr}
1293 Specify the guest-visible address of the virtual nameserver. The address must
1294 be different from the host address. Default is the 3rd IP in the guest network,
1295 i.e. x.x.x.3.
1297 @item tftp=@var{dir}
1298 When using the user mode network stack, activate a built-in TFTP
1299 server. The files in @var{dir} will be exposed as the root of a TFTP server.
1300 The TFTP client on the guest must be configured in binary mode (use the command
1301 @code{bin} of the Unix TFTP client).
1303 @item bootfile=@var{file}
1304 When using the user mode network stack, broadcast @var{file} as the BOOTP
1305 filename. In conjunction with @option{tftp}, this can be used to network boot
1306 a guest from a local directory.
1308 Example (using pxelinux):
1309 @example
1310 qemu -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1311 @end example
1313 @item smb=@var{dir}[,smbserver=@var{addr}]
1314 When using the user mode network stack, activate a built-in SMB
1315 server so that Windows OSes can access to the host files in @file{@var{dir}}
1316 transparently. The IP address of the SMB server can be set to @var{addr}. By
1317 default the 4th IP in the guest network is used, i.e. x.x.x.4.
1319 In the guest Windows OS, the line:
1320 @example
1321 10.0.2.4 smbserver
1322 @end example
1323 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1324 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1326 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
1328 Note that a SAMBA server must be installed on the host OS.
1329 QEMU was tested successfully with smbd versions from Red Hat 9,
1330 Fedora Core 3 and OpenSUSE 11.x.
1332 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1333 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1334 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1335 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1336 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1337 be bound to a specific host interface. If no connection type is set, TCP is
1338 used. This option can be given multiple times.
1340 For example, to redirect host X11 connection from screen 1 to guest
1341 screen 0, use the following:
1343 @example
1344 # on the host
1345 qemu -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1346 # this host xterm should open in the guest X11 server
1347 xterm -display :1
1348 @end example
1350 To redirect telnet connections from host port 5555 to telnet port on
1351 the guest, use the following:
1353 @example
1354 # on the host
1355 qemu -net user,hostfwd=tcp::5555-:23 [...]
1356 telnet localhost 5555
1357 @end example
1359 Then when you use on the host @code{telnet localhost 5555}, you
1360 connect to the guest telnet server.
1362 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1363 Forward guest TCP connections to the IP address @var{server} on port @var{port}
1364 to the character device @var{dev}. This option can be given multiple times.
1366 @end table
1368 Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
1369 processed and applied to -net user. Mixing them with the new configuration
1370 syntax gives undefined results. Their use for new applications is discouraged
1371 as they will be removed from future versions.
1373 @item -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}] [,script=@var{file}][,downscript=@var{dfile}]
1374 Connect the host TAP network interface @var{name} to VLAN @var{n}, use
1375 the network script @var{file} to configure it and the network script
1376 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
1377 automatically provides one. @option{fd}=@var{h} can be used to specify
1378 the handle of an already opened host TAP interface. The default network
1379 configure script is @file{/etc/qemu-ifup} and the default network
1380 deconfigure script is @file{/etc/qemu-ifdown}. Use @option{script=no}
1381 or @option{downscript=no} to disable script execution. Example:
1383 @example
1384 qemu linux.img -net nic -net tap
1385 @end example
1387 More complicated example (two NICs, each one connected to a TAP device)
1388 @example
1389 qemu linux.img -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
1390 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
1391 @end example
1393 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1395 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
1396 machine using a TCP socket connection. If @option{listen} is
1397 specified, QEMU waits for incoming connections on @var{port}
1398 (@var{host} is optional). @option{connect} is used to connect to
1399 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
1400 specifies an already opened TCP socket.
1402 Example:
1403 @example
1404 # launch a first QEMU instance
1405 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
1406 -net socket,listen=:1234
1407 # connect the VLAN 0 of this instance to the VLAN 0
1408 # of the first instance
1409 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
1410 -net socket,connect=127.0.0.1:1234
1411 @end example
1413 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1415 Create a VLAN @var{n} shared with another QEMU virtual
1416 machines using a UDP multicast socket, effectively making a bus for
1417 every QEMU with same multicast address @var{maddr} and @var{port}.
1418 NOTES:
1419 @enumerate
1420 @item
1421 Several QEMU can be running on different hosts and share same bus (assuming
1422 correct multicast setup for these hosts).
1423 @item
1424 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
1425 @url{http://user-mode-linux.sf.net}.
1426 @item
1427 Use @option{fd=h} to specify an already opened UDP multicast socket.
1428 @end enumerate
1430 Example:
1431 @example
1432 # launch one QEMU instance
1433 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
1434 -net socket,mcast=230.0.0.1:1234
1435 # launch another QEMU instance on same "bus"
1436 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
1437 -net socket,mcast=230.0.0.1:1234
1438 # launch yet another QEMU instance on same "bus"
1439 qemu linux.img -net nic,macaddr=52:54:00:12:34:58 \
1440 -net socket,mcast=230.0.0.1:1234
1441 @end example
1443 Example (User Mode Linux compat.):
1444 @example
1445 # launch QEMU instance (note mcast address selected
1446 # is UML's default)
1447 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
1448 -net socket,mcast=239.192.168.1:1102
1449 # launch UML
1450 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
1451 @end example
1453 Example (send packets from host's 1.2.3.4):
1454 @example
1455 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
1456 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
1457 @end example
1459 @item -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1460 Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
1461 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
1462 and MODE @var{octalmode} to change default ownership and permissions for
1463 communication port. This option is only available if QEMU has been compiled
1464 with vde support enabled.
1466 Example:
1467 @example
1468 # launch vde switch
1469 vde_switch -F -sock /tmp/myswitch
1470 # launch QEMU instance
1471 qemu linux.img -net nic -net vde,sock=/tmp/myswitch
1472 @end example
1474 @item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
1475 Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
1476 At most @var{len} bytes (64k by default) per packet are stored. The file format is
1477 libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
1479 @item -net none
1480 Indicate that no network devices should be configured. It is used to
1481 override the default configuration (@option{-net nic -net user}) which
1482 is activated if no @option{-net} options are provided.
1484 @end table
1485 ETEXI
1487 DEFHEADING()
1489 DEFHEADING(Character device options:)
1491 DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
1492 "-chardev null,id=id[,mux=on|off]\n"
1493 "-chardev socket,id=id[,host=host],port=host[,to=to][,ipv4][,ipv6][,nodelay]\n"
1494 " [,server][,nowait][,telnet][,mux=on|off] (tcp)\n"
1495 "-chardev socket,id=id,path=path[,server][,nowait][,telnet],[mux=on|off] (unix)\n"
1496 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
1497 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
1498 "-chardev msmouse,id=id[,mux=on|off]\n"
1499 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
1500 " [,mux=on|off]\n"
1501 "-chardev file,id=id,path=path[,mux=on|off]\n"
1502 "-chardev pipe,id=id,path=path[,mux=on|off]\n"
1503 #ifdef _WIN32
1504 "-chardev console,id=id[,mux=on|off]\n"
1505 "-chardev serial,id=id,path=path[,mux=on|off]\n"
1506 #else
1507 "-chardev pty,id=id[,mux=on|off]\n"
1508 "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n"
1509 #endif
1510 #ifdef CONFIG_BRLAPI
1511 "-chardev braille,id=id[,mux=on|off]\n"
1512 #endif
1513 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
1514 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
1515 "-chardev tty,id=id,path=path[,mux=on|off]\n"
1516 #endif
1517 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
1518 "-chardev parport,id=id,path=path[,mux=on|off]\n"
1519 #endif
1520 #if defined(CONFIG_SPICE)
1521 "-chardev spicevmc,id=id,name=name[,debug=debug]\n"
1522 #endif
1523 , QEMU_ARCH_ALL
1526 STEXI
1528 The general form of a character device option is:
1529 @table @option
1531 @item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
1532 @findex -chardev
1533 Backend is one of:
1534 @option{null},
1535 @option{socket},
1536 @option{udp},
1537 @option{msmouse},
1538 @option{vc},
1539 @option{file},
1540 @option{pipe},
1541 @option{console},
1542 @option{serial},
1543 @option{pty},
1544 @option{stdio},
1545 @option{braille},
1546 @option{tty},
1547 @option{parport},
1548 @option{spicevmc}.
1549 The specific backend will determine the applicable options.
1551 All devices must have an id, which can be any string up to 127 characters long.
1552 It is used to uniquely identify this device in other command line directives.
1554 A character device may be used in multiplexing mode by multiple front-ends.
1555 The key sequence of @key{Control-a} and @key{c} will rotate the input focus
1556 between attached front-ends. Specify @option{mux=on} to enable this mode.
1558 Options to each backend are described below.
1560 @item -chardev null ,id=@var{id}
1561 A void device. This device will not emit any data, and will drop any data it
1562 receives. The null backend does not take any options.
1564 @item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet]
1566 Create a two-way stream socket, which can be either a TCP or a unix socket. A
1567 unix socket will be created if @option{path} is specified. Behaviour is
1568 undefined if TCP options are specified for a unix socket.
1570 @option{server} specifies that the socket shall be a listening socket.
1572 @option{nowait} specifies that QEMU should not block waiting for a client to
1573 connect to a listening socket.
1575 @option{telnet} specifies that traffic on the socket should interpret telnet
1576 escape sequences.
1578 TCP and unix socket options are given below:
1580 @table @option
1582 @item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
1584 @option{host} for a listening socket specifies the local address to be bound.
1585 For a connecting socket species the remote host to connect to. @option{host} is
1586 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
1588 @option{port} for a listening socket specifies the local port to be bound. For a
1589 connecting socket specifies the port on the remote host to connect to.
1590 @option{port} can be given as either a port number or a service name.
1591 @option{port} is required.
1593 @option{to} is only relevant to listening sockets. If it is specified, and
1594 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
1595 to and including @option{to} until it succeeds. @option{to} must be specified
1596 as a port number.
1598 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1599 If neither is specified the socket may use either protocol.
1601 @option{nodelay} disables the Nagle algorithm.
1603 @item unix options: path=@var{path}
1605 @option{path} specifies the local path of the unix socket. @option{path} is
1606 required.
1608 @end table
1610 @item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
1612 Sends all traffic from the guest to a remote host over UDP.
1614 @option{host} specifies the remote host to connect to. If not specified it
1615 defaults to @code{localhost}.
1617 @option{port} specifies the port on the remote host to connect to. @option{port}
1618 is required.
1620 @option{localaddr} specifies the local address to bind to. If not specified it
1621 defaults to @code{0.0.0.0}.
1623 @option{localport} specifies the local port to bind to. If not specified any
1624 available local port will be used.
1626 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1627 If neither is specified the device may use either protocol.
1629 @item -chardev msmouse ,id=@var{id}
1631 Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
1632 take any options.
1634 @item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
1636 Connect to a QEMU text console. @option{vc} may optionally be given a specific
1637 size.
1639 @option{width} and @option{height} specify the width and height respectively of
1640 the console, in pixels.
1642 @option{cols} and @option{rows} specify that the console be sized to fit a text
1643 console with the given dimensions.
1645 @item -chardev file ,id=@var{id} ,path=@var{path}
1647 Log all traffic received from the guest to a file.
1649 @option{path} specifies the path of the file to be opened. This file will be
1650 created if it does not already exist, and overwritten if it does. @option{path}
1651 is required.
1653 @item -chardev pipe ,id=@var{id} ,path=@var{path}
1655 Create a two-way connection to the guest. The behaviour differs slightly between
1656 Windows hosts and other hosts:
1658 On Windows, a single duplex pipe will be created at
1659 @file{\\.pipe\@option{path}}.
1661 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
1662 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
1663 received by the guest. Data written by the guest can be read from
1664 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
1665 be present.
1667 @option{path} forms part of the pipe path as described above. @option{path} is
1668 required.
1670 @item -chardev console ,id=@var{id}
1672 Send traffic from the guest to QEMU's standard output. @option{console} does not
1673 take any options.
1675 @option{console} is only available on Windows hosts.
1677 @item -chardev serial ,id=@var{id} ,path=@option{path}
1679 Send traffic from the guest to a serial device on the host.
1681 @option{serial} is
1682 only available on Windows hosts.
1684 @option{path} specifies the name of the serial device to open.
1686 @item -chardev pty ,id=@var{id}
1688 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
1689 not take any options.
1691 @option{pty} is not available on Windows hosts.
1693 @item -chardev stdio ,id=@var{id} [,signal=on|off]
1694 Connect to standard input and standard output of the qemu process.
1696 @option{signal} controls if signals are enabled on the terminal, that includes
1697 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
1698 default, use @option{signal=off} to disable it.
1700 @option{stdio} is not available on Windows hosts.
1702 @item -chardev braille ,id=@var{id}
1704 Connect to a local BrlAPI server. @option{braille} does not take any options.
1706 @item -chardev tty ,id=@var{id} ,path=@var{path}
1708 Connect to a local tty device.
1710 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
1711 DragonFlyBSD hosts.
1713 @option{path} specifies the path to the tty. @option{path} is required.
1715 @item -chardev parport ,id=@var{id} ,path=@var{path}
1717 @option{parport} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
1719 Connect to a local parallel port.
1721 @option{path} specifies the path to the parallel port device. @option{path} is
1722 required.
1724 @item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
1726 @option{spicevmc} is only available when spice support is built in.
1728 @option{debug} debug level for spicevmc
1730 @option{name} name of spice channel to connect to
1732 Connect to a spice virtual machine channel, such as vdiport.
1734 @end table
1735 ETEXI
1737 DEFHEADING()
1739 STEXI
1740 DEFHEADING(Device URL Syntax:)
1742 In addition to using normal file images for the emulated storage devices,
1743 QEMU can also use networked resources such as iSCSI devices. These are
1744 specified using a special URL syntax.
1746 @table @option
1747 @item iSCSI
1748 iSCSI support allows QEMU to access iSCSI resources directly and use as
1749 images for the guest storage. Both disk and cdrom images are supported.
1751 Syntax for specifying iSCSI LUNs is
1752 ``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
1754 Example (without authentication):
1755 @example
1756 qemu -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
1757 --drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
1758 @end example
1760 Example (CHAP username/password via URL):
1761 @example
1762 qemu --drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
1763 @end example
1765 Example (CHAP username/password via environment variables):
1766 @example
1767 LIBISCSI_CHAP_USERNAME="user" \
1768 LIBISCSI_CHAP_PASSWORD="password" \
1769 qemu --drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
1770 @end example
1772 iSCSI support is an optional feature of QEMU and only available when
1773 compiled and linked against libiscsi.
1775 @item NBD
1776 QEMU supports NBD (Network Block Devices) both using TCP protocol as well
1777 as Unix Domain Sockets.
1779 Syntax for specifying a NBD device using TCP
1780 ``nbd:<server-ip>:<port>[:exportname=<export>]''
1782 Syntax for specifying a NBD device using Unix Domain Sockets
1783 ``nbd:unix:<domain-socket>[:exportname=<export>]''
1786 Example for TCP
1787 @example
1788 qemu --drive file=nbd:192.0.2.1:30000
1789 @end example
1791 Example for Unix Domain Sockets
1792 @example
1793 qemu --drive file=nbd:unix:/tmp/nbd-socket
1794 @end example
1796 @item Sheepdog
1797 Sheepdog is a distributed storage system for QEMU.
1798 QEMU supports using either local sheepdog devices or remote networked
1799 devices.
1801 Syntax for specifying a sheepdog device
1802 @table @list
1803 ``sheepdog:<vdiname>''
1805 ``sheepdog:<vdiname>:<snapid>''
1807 ``sheepdog:<vdiname>:<tag>''
1809 ``sheepdog:<host>:<port>:<vdiname>''
1811 ``sheepdog:<host>:<port>:<vdiname>:<snapid>''
1813 ``sheepdog:<host>:<port>:<vdiname>:<tag>''
1814 @end table
1816 Example
1817 @example
1818 qemu --drive file=sheepdog:192.0.2.1:30000:MyVirtualMachine
1819 @end example
1821 See also @url{http://http://www.osrg.net/sheepdog/}.
1823 @end table
1824 ETEXI
1826 DEFHEADING(Bluetooth(R) options:)
1828 DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
1829 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \
1830 "-bt hci,host[:id]\n" \
1831 " use host's HCI with the given name\n" \
1832 "-bt hci[,vlan=n]\n" \
1833 " emulate a standard HCI in virtual scatternet 'n'\n" \
1834 "-bt vhci[,vlan=n]\n" \
1835 " add host computer to virtual scatternet 'n' using VHCI\n" \
1836 "-bt device:dev[,vlan=n]\n" \
1837 " emulate a bluetooth device 'dev' in scatternet 'n'\n",
1838 QEMU_ARCH_ALL)
1839 STEXI
1840 @table @option
1842 @item -bt hci[...]
1843 @findex -bt
1844 Defines the function of the corresponding Bluetooth HCI. -bt options
1845 are matched with the HCIs present in the chosen machine type. For
1846 example when emulating a machine with only one HCI built into it, only
1847 the first @code{-bt hci[...]} option is valid and defines the HCI's
1848 logic. The Transport Layer is decided by the machine type. Currently
1849 the machines @code{n800} and @code{n810} have one HCI and all other
1850 machines have none.
1852 @anchor{bt-hcis}
1853 The following three types are recognized:
1855 @table @option
1856 @item -bt hci,null
1857 (default) The corresponding Bluetooth HCI assumes no internal logic
1858 and will not respond to any HCI commands or emit events.
1860 @item -bt hci,host[:@var{id}]
1861 (@code{bluez} only) The corresponding HCI passes commands / events
1862 to / from the physical HCI identified by the name @var{id} (default:
1863 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
1864 capable systems like Linux.
1866 @item -bt hci[,vlan=@var{n}]
1867 Add a virtual, standard HCI that will participate in the Bluetooth
1868 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
1869 VLANs, devices inside a bluetooth network @var{n} can only communicate
1870 with other devices in the same network (scatternet).
1871 @end table
1873 @item -bt vhci[,vlan=@var{n}]
1874 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
1875 to the host bluetooth stack instead of to the emulated target. This
1876 allows the host and target machines to participate in a common scatternet
1877 and communicate. Requires the Linux @code{vhci} driver installed. Can
1878 be used as following:
1880 @example
1881 qemu [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
1882 @end example
1884 @item -bt device:@var{dev}[,vlan=@var{n}]
1885 Emulate a bluetooth device @var{dev} and place it in network @var{n}
1886 (default @code{0}). QEMU can only emulate one type of bluetooth devices
1887 currently:
1889 @table @option
1890 @item keyboard
1891 Virtual wireless keyboard implementing the HIDP bluetooth profile.
1892 @end table
1893 @end table
1894 ETEXI
1896 DEFHEADING()
1898 DEFHEADING(Linux/Multiboot boot specific:)
1899 STEXI
1901 When using these options, you can use a given Linux or Multiboot
1902 kernel without installing it in the disk image. It can be useful
1903 for easier testing of various kernels.
1905 @table @option
1906 ETEXI
1908 DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
1909 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL)
1910 STEXI
1911 @item -kernel @var{bzImage}
1912 @findex -kernel
1913 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
1914 or in multiboot format.
1915 ETEXI
1917 DEF("append", HAS_ARG, QEMU_OPTION_append, \
1918 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL)
1919 STEXI
1920 @item -append @var{cmdline}
1921 @findex -append
1922 Use @var{cmdline} as kernel command line
1923 ETEXI
1925 DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
1926 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL)
1927 STEXI
1928 @item -initrd @var{file}
1929 @findex -initrd
1930 Use @var{file} as initial ram disk.
1932 @item -initrd "@var{file1} arg=foo,@var{file2}"
1934 This syntax is only available with multiboot.
1936 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
1937 first module.
1938 ETEXI
1940 STEXI
1941 @end table
1942 ETEXI
1944 DEFHEADING()
1946 DEFHEADING(Debug/Expert options:)
1948 STEXI
1949 @table @option
1950 ETEXI
1952 DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
1953 "-serial dev redirect the serial port to char device 'dev'\n",
1954 QEMU_ARCH_ALL)
1955 STEXI
1956 @item -serial @var{dev}
1957 @findex -serial
1958 Redirect the virtual serial port to host character device
1959 @var{dev}. The default device is @code{vc} in graphical mode and
1960 @code{stdio} in non graphical mode.
1962 This option can be used several times to simulate up to 4 serial
1963 ports.
1965 Use @code{-serial none} to disable all serial ports.
1967 Available character devices are:
1968 @table @option
1969 @item vc[:@var{W}x@var{H}]
1970 Virtual console. Optionally, a width and height can be given in pixel with
1971 @example
1972 vc:800x600
1973 @end example
1974 It is also possible to specify width or height in characters:
1975 @example
1976 vc:80Cx24C
1977 @end example
1978 @item pty
1979 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
1980 @item none
1981 No device is allocated.
1982 @item null
1983 void device
1984 @item /dev/XXX
1985 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
1986 parameters are set according to the emulated ones.
1987 @item /dev/parport@var{N}
1988 [Linux only, parallel port only] Use host parallel port
1989 @var{N}. Currently SPP and EPP parallel port features can be used.
1990 @item file:@var{filename}
1991 Write output to @var{filename}. No character can be read.
1992 @item stdio
1993 [Unix only] standard input/output
1994 @item pipe:@var{filename}
1995 name pipe @var{filename}
1996 @item COM@var{n}
1997 [Windows only] Use host serial port @var{n}
1998 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
1999 This implements UDP Net Console.
2000 When @var{remote_host} or @var{src_ip} are not specified
2001 they default to @code{0.0.0.0}.
2002 When not using a specified @var{src_port} a random port is automatically chosen.
2004 If you just want a simple readonly console you can use @code{netcat} or
2005 @code{nc}, by starting qemu with: @code{-serial udp::4555} and nc as:
2006 @code{nc -u -l -p 4555}. Any time qemu writes something to that port it
2007 will appear in the netconsole session.
2009 If you plan to send characters back via netconsole or you want to stop
2010 and start qemu a lot of times, you should have qemu use the same
2011 source port each time by using something like @code{-serial
2012 udp::4555@@:4556} to qemu. Another approach is to use a patched
2013 version of netcat which can listen to a TCP port and send and receive
2014 characters via udp. If you have a patched version of netcat which
2015 activates telnet remote echo and single char transfer, then you can
2016 use the following options to step up a netcat redirector to allow
2017 telnet on port 5555 to access the qemu port.
2018 @table @code
2019 @item Qemu Options:
2020 -serial udp::4555@@:4556
2021 @item netcat options:
2022 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
2023 @item telnet options:
2024 localhost 5555
2025 @end table
2027 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay]
2028 The TCP Net Console has two modes of operation. It can send the serial
2029 I/O to a location or wait for a connection from a location. By default
2030 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
2031 the @var{server} option QEMU will wait for a client socket application
2032 to connect to the port before continuing, unless the @code{nowait}
2033 option was specified. The @code{nodelay} option disables the Nagle buffering
2034 algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only
2035 one TCP connection at a time is accepted. You can use @code{telnet} to
2036 connect to the corresponding character device.
2037 @table @code
2038 @item Example to send tcp console to 192.168.0.2 port 4444
2039 -serial tcp:192.168.0.2:4444
2040 @item Example to listen and wait on port 4444 for connection
2041 -serial tcp::4444,server
2042 @item Example to not wait and listen on ip 192.168.0.100 port 4444
2043 -serial tcp:192.168.0.100:4444,server,nowait
2044 @end table
2046 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
2047 The telnet protocol is used instead of raw tcp sockets. The options
2048 work the same as if you had specified @code{-serial tcp}. The
2049 difference is that the port acts like a telnet server or client using
2050 telnet option negotiation. This will also allow you to send the
2051 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
2052 sequence. Typically in unix telnet you do it with Control-] and then
2053 type "send break" followed by pressing the enter key.
2055 @item unix:@var{path}[,server][,nowait]
2056 A unix domain socket is used instead of a tcp socket. The option works the
2057 same as if you had specified @code{-serial tcp} except the unix domain socket
2058 @var{path} is used for connections.
2060 @item mon:@var{dev_string}
2061 This is a special option to allow the monitor to be multiplexed onto
2062 another serial port. The monitor is accessed with key sequence of
2063 @key{Control-a} and then pressing @key{c}. See monitor access
2064 @ref{pcsys_keys} in the -nographic section for more keys.
2065 @var{dev_string} should be any one of the serial devices specified
2066 above. An example to multiplex the monitor onto a telnet server
2067 listening on port 4444 would be:
2068 @table @code
2069 @item -serial mon:telnet::4444,server,nowait
2070 @end table
2072 @item braille
2073 Braille device. This will use BrlAPI to display the braille output on a real
2074 or fake device.
2076 @item msmouse
2077 Three button serial mouse. Configure the guest to use Microsoft protocol.
2078 @end table
2079 ETEXI
2081 DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
2082 "-parallel dev redirect the parallel port to char device 'dev'\n",
2083 QEMU_ARCH_ALL)
2084 STEXI
2085 @item -parallel @var{dev}
2086 @findex -parallel
2087 Redirect the virtual parallel port to host device @var{dev} (same
2088 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
2089 be used to use hardware devices connected on the corresponding host
2090 parallel port.
2092 This option can be used several times to simulate up to 3 parallel
2093 ports.
2095 Use @code{-parallel none} to disable all parallel ports.
2096 ETEXI
2098 DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
2099 "-monitor dev redirect the monitor to char device 'dev'\n",
2100 QEMU_ARCH_ALL)
2101 STEXI
2102 @item -monitor @var{dev}
2103 @findex -monitor
2104 Redirect the monitor to host device @var{dev} (same devices as the
2105 serial port).
2106 The default device is @code{vc} in graphical mode and @code{stdio} in
2107 non graphical mode.
2108 ETEXI
2109 DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
2110 "-qmp dev like -monitor but opens in 'control' mode\n",
2111 QEMU_ARCH_ALL)
2112 STEXI
2113 @item -qmp @var{dev}
2114 @findex -qmp
2115 Like -monitor but opens in 'control' mode.
2116 ETEXI
2118 DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
2119 "-mon chardev=[name][,mode=readline|control][,default]\n", QEMU_ARCH_ALL)
2120 STEXI
2121 @item -mon chardev=[name][,mode=readline|control][,default]
2122 @findex -mon
2123 Setup monitor on chardev @var{name}.
2124 ETEXI
2126 DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
2127 "-debugcon dev redirect the debug console to char device 'dev'\n",
2128 QEMU_ARCH_ALL)
2129 STEXI
2130 @item -debugcon @var{dev}
2131 @findex -debugcon
2132 Redirect the debug console to host device @var{dev} (same devices as the
2133 serial port). The debug console is an I/O port which is typically port
2134 0xe9; writing to that I/O port sends output to this device.
2135 The default device is @code{vc} in graphical mode and @code{stdio} in
2136 non graphical mode.
2137 ETEXI
2139 DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
2140 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL)
2141 STEXI
2142 @item -pidfile @var{file}
2143 @findex -pidfile
2144 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
2145 from a script.
2146 ETEXI
2148 DEF("singlestep", 0, QEMU_OPTION_singlestep, \
2149 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL)
2150 STEXI
2151 @item -singlestep
2152 @findex -singlestep
2153 Run the emulation in single step mode.
2154 ETEXI
2156 DEF("S", 0, QEMU_OPTION_S, \
2157 "-S freeze CPU at startup (use 'c' to start execution)\n",
2158 QEMU_ARCH_ALL)
2159 STEXI
2160 @item -S
2161 @findex -S
2162 Do not start CPU at startup (you must type 'c' in the monitor).
2163 ETEXI
2165 DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
2166 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL)
2167 STEXI
2168 @item -gdb @var{dev}
2169 @findex -gdb
2170 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
2171 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
2172 stdio are reasonable use case. The latter is allowing to start qemu from
2173 within gdb and establish the connection via a pipe:
2174 @example
2175 (gdb) target remote | exec qemu -gdb stdio ...
2176 @end example
2177 ETEXI
2179 DEF("s", 0, QEMU_OPTION_s, \
2180 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
2181 QEMU_ARCH_ALL)
2182 STEXI
2183 @item -s
2184 @findex -s
2185 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
2186 (@pxref{gdb_usage}).
2187 ETEXI
2189 DEF("d", HAS_ARG, QEMU_OPTION_d, \
2190 "-d item1,... output log to /tmp/qemu.log (use -d ? for a list of log items)\n",
2191 QEMU_ARCH_ALL)
2192 STEXI
2193 @item -d
2194 @findex -d
2195 Output log in /tmp/qemu.log
2196 ETEXI
2198 DEF("D", HAS_ARG, QEMU_OPTION_D, \
2199 "-D logfile output log to logfile (instead of the default /tmp/qemu.log)\n",
2200 QEMU_ARCH_ALL)
2201 STEXI
2202 @item -D
2203 @findex -D
2204 Output log in logfile instead of /tmp/qemu.log
2205 ETEXI
2207 DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
2208 "-hdachs c,h,s[,t]\n" \
2209 " force hard disk 0 physical geometry and the optional BIOS\n" \
2210 " translation (t=none or lba) (usually qemu can guess them)\n",
2211 QEMU_ARCH_ALL)
2212 STEXI
2213 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
2214 @findex -hdachs
2215 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
2216 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
2217 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
2218 all those parameters. This option is useful for old MS-DOS disk
2219 images.
2220 ETEXI
2222 DEF("L", HAS_ARG, QEMU_OPTION_L, \
2223 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
2224 QEMU_ARCH_ALL)
2225 STEXI
2226 @item -L @var{path}
2227 @findex -L
2228 Set the directory for the BIOS, VGA BIOS and keymaps.
2229 ETEXI
2231 DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
2232 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL)
2233 STEXI
2234 @item -bios @var{file}
2235 @findex -bios
2236 Set the filename for the BIOS.
2237 ETEXI
2239 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
2240 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL)
2241 STEXI
2242 @item -enable-kvm
2243 @findex -enable-kvm
2244 Enable KVM full virtualization support. This option is only available
2245 if KVM support is enabled when compiling.
2246 ETEXI
2248 DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
2249 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL)
2250 DEF("xen-create", 0, QEMU_OPTION_xen_create,
2251 "-xen-create create domain using xen hypercalls, bypassing xend\n"
2252 " warning: should not be used when xend is in use\n",
2253 QEMU_ARCH_ALL)
2254 DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
2255 "-xen-attach attach to existing xen domain\n"
2256 " xend will use this when starting qemu\n",
2257 QEMU_ARCH_ALL)
2258 STEXI
2259 @item -xen-domid @var{id}
2260 @findex -xen-domid
2261 Specify xen guest domain @var{id} (XEN only).
2262 @item -xen-create
2263 @findex -xen-create
2264 Create domain using xen hypercalls, bypassing xend.
2265 Warning: should not be used when xend is in use (XEN only).
2266 @item -xen-attach
2267 @findex -xen-attach
2268 Attach to existing xen domain.
2269 xend will use this when starting qemu (XEN only).
2270 ETEXI
2272 DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
2273 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL)
2274 STEXI
2275 @item -no-reboot
2276 @findex -no-reboot
2277 Exit instead of rebooting.
2278 ETEXI
2280 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
2281 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL)
2282 STEXI
2283 @item -no-shutdown
2284 @findex -no-shutdown
2285 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
2286 This allows for instance switching to monitor to commit changes to the
2287 disk image.
2288 ETEXI
2290 DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
2291 "-loadvm [tag|id]\n" \
2292 " start right away with a saved state (loadvm in monitor)\n",
2293 QEMU_ARCH_ALL)
2294 STEXI
2295 @item -loadvm @var{file}
2296 @findex -loadvm
2297 Start right away with a saved state (@code{loadvm} in monitor)
2298 ETEXI
2300 #ifndef _WIN32
2301 DEF("daemonize", 0, QEMU_OPTION_daemonize, \
2302 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
2303 #endif
2304 STEXI
2305 @item -daemonize
2306 @findex -daemonize
2307 Daemonize the QEMU process after initialization. QEMU will not detach from
2308 standard IO until it is ready to receive connections on any of its devices.
2309 This option is a useful way for external programs to launch QEMU without having
2310 to cope with initialization race conditions.
2311 ETEXI
2313 DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
2314 "-option-rom rom load a file, rom, into the option ROM space\n",
2315 QEMU_ARCH_ALL)
2316 STEXI
2317 @item -option-rom @var{file}
2318 @findex -option-rom
2319 Load the contents of @var{file} as an option ROM.
2320 This option is useful to load things like EtherBoot.
2321 ETEXI
2323 DEF("clock", HAS_ARG, QEMU_OPTION_clock, \
2324 "-clock force the use of the given methods for timer alarm.\n" \
2325 " To see what timers are available use -clock ?\n",
2326 QEMU_ARCH_ALL)
2327 STEXI
2328 @item -clock @var{method}
2329 @findex -clock
2330 Force the use of the given methods for timer alarm. To see what timers
2331 are available use -clock ?.
2332 ETEXI
2334 HXCOMM Options deprecated by -rtc
2335 DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
2336 DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
2338 DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
2339 "-rtc [base=utc|localtime|date][,clock=host|vm][,driftfix=none|slew]\n" \
2340 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
2341 QEMU_ARCH_ALL)
2343 STEXI
2345 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
2346 @findex -rtc
2347 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
2348 UTC or local time, respectively. @code{localtime} is required for correct date in
2349 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
2350 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
2352 By default the RTC is driven by the host system time. This allows to use the
2353 RTC as accurate reference clock inside the guest, specifically if the host
2354 time is smoothly following an accurate external reference clock, e.g. via NTP.
2355 If you want to isolate the guest time from the host, even prevent it from
2356 progressing during suspension, you can set @option{clock} to @code{vm} instead.
2358 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
2359 specifically with Windows' ACPI HAL. This option will try to figure out how
2360 many timer interrupts were not processed by the Windows guest and will
2361 re-inject them.
2362 ETEXI
2364 DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
2365 "-icount [N|auto]\n" \
2366 " enable virtual instruction counter with 2^N clock ticks per\n" \
2367 " instruction\n", QEMU_ARCH_ALL)
2368 STEXI
2369 @item -icount [@var{N}|auto]
2370 @findex -icount
2371 Enable virtual instruction counter. The virtual cpu will execute one
2372 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
2373 then the virtual cpu speed will be automatically adjusted to keep virtual
2374 time within a few seconds of real time.
2376 Note that while this option can give deterministic behavior, it does not
2377 provide cycle accurate emulation. Modern CPUs contain superscalar out of
2378 order cores with complex cache hierarchies. The number of instructions
2379 executed often has little or no correlation with actual performance.
2380 ETEXI
2382 DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
2383 "-watchdog i6300esb|ib700\n" \
2384 " enable virtual hardware watchdog [default=none]\n",
2385 QEMU_ARCH_ALL)
2386 STEXI
2387 @item -watchdog @var{model}
2388 @findex -watchdog
2389 Create a virtual hardware watchdog device. Once enabled (by a guest
2390 action), the watchdog must be periodically polled by an agent inside
2391 the guest or else the guest will be restarted.
2393 The @var{model} is the model of hardware watchdog to emulate. Choices
2394 for model are: @code{ib700} (iBASE 700) which is a very simple ISA
2395 watchdog with a single timer, or @code{i6300esb} (Intel 6300ESB I/O
2396 controller hub) which is a much more featureful PCI-based dual-timer
2397 watchdog. Choose a model for which your guest has drivers.
2399 Use @code{-watchdog ?} to list available hardware models. Only one
2400 watchdog can be enabled for a guest.
2401 ETEXI
2403 DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
2404 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
2405 " action when watchdog fires [default=reset]\n",
2406 QEMU_ARCH_ALL)
2407 STEXI
2408 @item -watchdog-action @var{action}
2410 The @var{action} controls what QEMU will do when the watchdog timer
2411 expires.
2412 The default is
2413 @code{reset} (forcefully reset the guest).
2414 Other possible actions are:
2415 @code{shutdown} (attempt to gracefully shutdown the guest),
2416 @code{poweroff} (forcefully poweroff the guest),
2417 @code{pause} (pause the guest),
2418 @code{debug} (print a debug message and continue), or
2419 @code{none} (do nothing).
2421 Note that the @code{shutdown} action requires that the guest responds
2422 to ACPI signals, which it may not be able to do in the sort of
2423 situations where the watchdog would have expired, and thus
2424 @code{-watchdog-action shutdown} is not recommended for production use.
2426 Examples:
2428 @table @code
2429 @item -watchdog i6300esb -watchdog-action pause
2430 @item -watchdog ib700
2431 @end table
2432 ETEXI
2434 DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
2435 "-echr chr set terminal escape character instead of ctrl-a\n",
2436 QEMU_ARCH_ALL)
2437 STEXI
2439 @item -echr @var{numeric_ascii_value}
2440 @findex -echr
2441 Change the escape character used for switching to the monitor when using
2442 monitor and serial sharing. The default is @code{0x01} when using the
2443 @code{-nographic} option. @code{0x01} is equal to pressing
2444 @code{Control-a}. You can select a different character from the ascii
2445 control keys where 1 through 26 map to Control-a through Control-z. For
2446 instance you could use the either of the following to change the escape
2447 character to Control-t.
2448 @table @code
2449 @item -echr 0x14
2450 @item -echr 20
2451 @end table
2452 ETEXI
2454 DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
2455 "-virtioconsole c\n" \
2456 " set virtio console\n", QEMU_ARCH_ALL)
2457 STEXI
2458 @item -virtioconsole @var{c}
2459 @findex -virtioconsole
2460 Set virtio console.
2462 This option is maintained for backward compatibility.
2464 Please use @code{-device virtconsole} for the new way of invocation.
2465 ETEXI
2467 DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
2468 "-show-cursor show cursor\n", QEMU_ARCH_ALL)
2469 STEXI
2470 @item -show-cursor
2471 @findex -show-cursor
2472 Show cursor.
2473 ETEXI
2475 DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
2476 "-tb-size n set TB size\n", QEMU_ARCH_ALL)
2477 STEXI
2478 @item -tb-size @var{n}
2479 @findex -tb-size
2480 Set TB size.
2481 ETEXI
2483 DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
2484 "-incoming p prepare for incoming migration, listen on port p\n",
2485 QEMU_ARCH_ALL)
2486 STEXI
2487 @item -incoming @var{port}
2488 @findex -incoming
2489 Prepare for incoming migration, listen on @var{port}.
2490 ETEXI
2492 DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
2493 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL)
2494 STEXI
2495 @item -nodefaults
2496 @findex -nodefaults
2497 Don't create default devices.
2498 ETEXI
2500 #ifndef _WIN32
2501 DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
2502 "-chroot dir chroot to dir just before starting the VM\n",
2503 QEMU_ARCH_ALL)
2504 #endif
2505 STEXI
2506 @item -chroot @var{dir}
2507 @findex -chroot
2508 Immediately before starting guest execution, chroot to the specified
2509 directory. Especially useful in combination with -runas.
2510 ETEXI
2512 #ifndef _WIN32
2513 DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
2514 "-runas user change to user id user just before starting the VM\n",
2515 QEMU_ARCH_ALL)
2516 #endif
2517 STEXI
2518 @item -runas @var{user}
2519 @findex -runas
2520 Immediately before starting guest execution, drop root privileges, switching
2521 to the specified user.
2522 ETEXI
2524 DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
2525 "-prom-env variable=value\n"
2526 " set OpenBIOS nvram variables\n",
2527 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
2528 STEXI
2529 @item -prom-env @var{variable}=@var{value}
2530 @findex -prom-env
2531 Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
2532 ETEXI
2533 DEF("semihosting", 0, QEMU_OPTION_semihosting,
2534 "-semihosting semihosting mode\n", QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA)
2535 STEXI
2536 @item -semihosting
2537 @findex -semihosting
2538 Semihosting mode (ARM, M68K, Xtensa only).
2539 ETEXI
2540 DEF("old-param", 0, QEMU_OPTION_old_param,
2541 "-old-param old param mode\n", QEMU_ARCH_ARM)
2542 STEXI
2543 @item -old-param
2544 @findex -old-param (ARM)
2545 Old param mode (ARM only).
2546 ETEXI
2548 DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
2549 "-readconfig <file>\n", QEMU_ARCH_ALL)
2550 STEXI
2551 @item -readconfig @var{file}
2552 @findex -readconfig
2553 Read device configuration from @var{file}.
2554 ETEXI
2555 DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
2556 "-writeconfig <file>\n"
2557 " read/write config file\n", QEMU_ARCH_ALL)
2558 STEXI
2559 @item -writeconfig @var{file}
2560 @findex -writeconfig
2561 Write device configuration to @var{file}.
2562 ETEXI
2563 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig,
2564 "-nodefconfig\n"
2565 " do not load default config files at startup\n",
2566 QEMU_ARCH_ALL)
2567 STEXI
2568 @item -nodefconfig
2569 @findex -nodefconfig
2570 Normally QEMU loads a configuration file from @var{sysconfdir}/qemu.conf and
2571 @var{sysconfdir}/target-@var{ARCH}.conf on startup. The @code{-nodefconfig}
2572 option will prevent QEMU from loading these configuration files at startup.
2573 ETEXI
2574 DEF("trace", HAS_ARG, QEMU_OPTION_trace,
2575 "-trace [events=<file>][,file=<file>]\n"
2576 " specify tracing options\n",
2577 QEMU_ARCH_ALL)
2578 STEXI
2579 HXCOMM This line is not accurate, as some sub-options are backend-specific but
2580 HXCOMM HX does not support conditional compilation of text.
2581 @item -trace [events=@var{file}][,file=@var{file}]
2582 @findex -trace
2584 Specify tracing options.
2586 @table @option
2587 @item events=@var{file}
2588 Immediately enable events listed in @var{file}.
2589 The file must contain one event name (as listed in the @var{trace-events} file)
2590 per line.
2591 This option is only available if QEMU has been compiled with
2592 either @var{simple} or @var{stderr} tracing backend.
2593 @item file=@var{file}
2594 Log output traces to @var{file}.
2596 This option is only available if QEMU has been compiled with
2597 the @var{simple} tracing backend.
2598 @end table
2599 ETEXI
2601 HXCOMM This is the last statement. Insert new options before this line!
2602 STEXI
2603 @end table
2604 ETEXI