hostmem: allow preallocation of any memory region
[qemu.git] / qemu-options.hx
blobca75760b277ed9390d465de2f97b4d824d2f476b
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 help' for list)\n"
33 " property accel=accel1[:accel2[:...]] selects accelerator\n"
34 " supported accelerators are kvm, xen, tcg (default: tcg)\n"
35 " kernel_irqchip=on|off controls accelerated irqchip support\n"
36 " kvm_shadow_mem=size of KVM shadow MMU\n"
37 " dump-guest-core=on|off include guest memory in a core dump (default=on)\n"
38 " mem-merge=on|off controls memory merge support (default: on)\n",
39 QEMU_ARCH_ALL)
40 STEXI
41 @item -machine [type=]@var{name}[,prop=@var{value}[,...]]
42 @findex -machine
43 Select the emulated machine by @var{name}. Use @code{-machine help} to list
44 available machines. Supported machine properties are:
45 @table @option
46 @item accel=@var{accels1}[:@var{accels2}[:...]]
47 This is used to enable an accelerator. Depending on the target architecture,
48 kvm, xen, or tcg can be available. By default, tcg is used. If there is more
49 than one accelerator specified, the next one is used if the previous one fails
50 to initialize.
51 @item kernel_irqchip=on|off
52 Enables in-kernel irqchip support for the chosen accelerator when available.
53 @item kvm_shadow_mem=size
54 Defines the size of the KVM shadow MMU.
55 @item dump-guest-core=on|off
56 Include guest memory in a core dump. The default is on.
57 @item mem-merge=on|off
58 Enables or disables memory merge support. This feature, when supported by
59 the host, de-duplicates identical memory pages among VMs instances
60 (enabled by default).
61 @end table
62 ETEXI
64 HXCOMM Deprecated by -machine
65 DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL)
67 DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
68 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL)
69 STEXI
70 @item -cpu @var{model}
71 @findex -cpu
72 Select CPU model (@code{-cpu help} for list and additional feature selection)
73 ETEXI
75 DEF("smp", HAS_ARG, QEMU_OPTION_smp,
76 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
77 " set the number of CPUs to 'n' [default=1]\n"
78 " maxcpus= maximum number of total cpus, including\n"
79 " offline CPUs for hotplug, etc\n"
80 " cores= number of CPU cores on one socket\n"
81 " threads= number of threads on one CPU core\n"
82 " sockets= number of discrete sockets in the system\n",
83 QEMU_ARCH_ALL)
84 STEXI
85 @item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
86 @findex -smp
87 Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
88 CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
89 to 4.
90 For the PC target, the number of @var{cores} per socket, the number
91 of @var{threads} per cores and the total number of @var{sockets} can be
92 specified. Missing values will be computed. If any on the three values is
93 given, the total number of CPUs @var{n} can be omitted. @var{maxcpus}
94 specifies the maximum number of hotpluggable CPUs.
95 ETEXI
97 DEF("numa", HAS_ARG, QEMU_OPTION_numa,
98 "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n"
99 "-numa node[,memdev=id][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL)
100 STEXI
101 @item -numa node[,mem=@var{size}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}]
102 @item -numa node[,memdev=@var{id}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}]
103 @findex -numa
104 Simulate a multi node NUMA system. If @samp{mem}, @samp{memdev}
105 and @samp{cpus} are omitted, resources are split equally. Also, note
106 that the -@option{numa} option doesn't allocate any of the specified
107 resources. That is, it just assigns existing resources to NUMA nodes. This
108 means that one still has to use the @option{-m}, @option{-smp} options
109 to allocate RAM and VCPUs respectively, and possibly @option{-object}
110 to specify the memory backend for the @samp{memdev} suboption.
112 @samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, if one
113 node uses @samp{memdev}, all of them have to use it.
114 ETEXI
116 DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
117 "-add-fd fd=fd,set=set[,opaque=opaque]\n"
118 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL)
119 STEXI
120 @item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}]
121 @findex -add-fd
123 Add a file descriptor to an fd set. Valid options are:
125 @table @option
126 @item fd=@var{fd}
127 This option defines the file descriptor of which a duplicate is added to fd set.
128 The file descriptor cannot be stdin, stdout, or stderr.
129 @item set=@var{set}
130 This option defines the ID of the fd set to add the file descriptor to.
131 @item opaque=@var{opaque}
132 This option defines a free-form string that can be used to describe @var{fd}.
133 @end table
135 You can open an image using pre-opened file descriptors from an fd set:
136 @example
137 qemu-system-i386
138 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
139 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
140 -drive file=/dev/fdset/2,index=0,media=disk
141 @end example
142 ETEXI
144 DEF("set", HAS_ARG, QEMU_OPTION_set,
145 "-set group.id.arg=value\n"
146 " set <arg> parameter for item <id> of type <group>\n"
147 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL)
148 STEXI
149 @item -set @var{group}.@var{id}.@var{arg}=@var{value}
150 @findex -set
151 Set parameter @var{arg} for item @var{id} of type @var{group}\n"
152 ETEXI
154 DEF("global", HAS_ARG, QEMU_OPTION_global,
155 "-global driver.prop=value\n"
156 " set a global default for a driver property\n",
157 QEMU_ARCH_ALL)
158 STEXI
159 @item -global @var{driver}.@var{prop}=@var{value}
160 @findex -global
161 Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.:
163 @example
164 qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk
165 @end example
167 In particular, you can use this to set driver properties for devices which are
168 created automatically by the machine model. To create a device which is not
169 created automatically and set properties on it, use -@option{device}.
170 ETEXI
172 DEF("boot", HAS_ARG, QEMU_OPTION_boot,
173 "-boot [order=drives][,once=drives][,menu=on|off]\n"
174 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
175 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
176 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n"
177 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n"
178 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n",
179 QEMU_ARCH_ALL)
180 STEXI
181 @item -boot [order=@var{drives}][,once=@var{drives}][,menu=on|off][,splash=@var{sp_name}][,splash-time=@var{sp_time}][,reboot-timeout=@var{rb_timeout}][,strict=on|off]
182 @findex -boot
183 Specify boot order @var{drives} as a string of drive letters. Valid
184 drive letters depend on the target achitecture. The x86 PC uses: a, b
185 (floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
186 from network adapter 1-4), hard disk boot is the default. To apply a
187 particular boot order only on the first startup, specify it via
188 @option{once}.
190 Interactive boot menus/prompts can be enabled via @option{menu=on} as far
191 as firmware/BIOS supports them. The default is non-interactive boot.
193 A splash picture could be passed to bios, enabling user to show it as logo,
194 when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
195 supports them. Currently Seabios for X86 system support it.
196 limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
197 format(true color). The resolution should be supported by the SVGA mode, so
198 the recommended is 320x240, 640x480, 800x640.
200 A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms
201 when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not
202 reboot, qemu passes '-1' to bios by default. Currently Seabios for X86
203 system support it.
205 Do strict boot via @option{strict=on} as far as firmware/BIOS
206 supports it. This only effects when boot priority is changed by
207 bootindex options. The default is non-strict boot.
209 @example
210 # try to boot from network first, then from hard disk
211 qemu-system-i386 -boot order=nc
212 # boot from CD-ROM first, switch back to default order after reboot
213 qemu-system-i386 -boot once=d
214 # boot with a splash picture for 5 seconds.
215 qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
216 @end example
218 Note: The legacy format '-boot @var{drives}' is still supported but its
219 use is discouraged as it may be removed from future versions.
220 ETEXI
222 DEF("m", HAS_ARG, QEMU_OPTION_m,
223 "-m[emory] [size=]megs[,slots=n,maxmem=size]\n"
224 " configure guest RAM\n"
225 " size: initial amount of guest memory (default: "
226 stringify(DEFAULT_RAM_SIZE) "MiB)\n"
227 " slots: number of hotplug slots (default: none)\n"
228 " maxmem: maximum amount of guest memory (default: none)\n",
229 QEMU_ARCH_ALL)
230 STEXI
231 @item -m [size=]@var{megs}
232 @findex -m
233 Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally,
234 a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or
235 gigabytes respectively. Optional pair @var{slots}, @var{maxmem} could be used
236 to set amount of hotluggable memory slots and possible maximum amount of memory.
237 ETEXI
239 DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
240 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
241 STEXI
242 @item -mem-path @var{path}
243 @findex -mem-path
244 Allocate guest RAM from a temporarily created file in @var{path}.
245 ETEXI
247 DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
248 "-mem-prealloc preallocate guest memory (use with -mem-path)\n",
249 QEMU_ARCH_ALL)
250 STEXI
251 @item -mem-prealloc
252 @findex -mem-prealloc
253 Preallocate memory when using -mem-path.
254 ETEXI
256 DEF("k", HAS_ARG, QEMU_OPTION_k,
257 "-k language use keyboard layout (for example 'fr' for French)\n",
258 QEMU_ARCH_ALL)
259 STEXI
260 @item -k @var{language}
261 @findex -k
262 Use keyboard layout @var{language} (for example @code{fr} for
263 French). This option is only needed where it is not easy to get raw PC
264 keycodes (e.g. on Macs, with some X11 servers or with a VNC
265 display). You don't normally need to use it on PC/Linux or PC/Windows
266 hosts.
268 The available layouts are:
269 @example
270 ar de-ch es fo fr-ca hu ja mk no pt-br sv
271 da en-gb et fr fr-ch is lt nl pl ru th
272 de en-us fi fr-be hr it lv nl-be pt sl tr
273 @end example
275 The default is @code{en-us}.
276 ETEXI
279 DEF("audio-help", 0, QEMU_OPTION_audio_help,
280 "-audio-help print list of audio drivers and their options\n",
281 QEMU_ARCH_ALL)
282 STEXI
283 @item -audio-help
284 @findex -audio-help
285 Will show the audio subsystem help: list of drivers, tunable
286 parameters.
287 ETEXI
289 DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
290 "-soundhw c1,... enable audio support\n"
291 " and only specified sound cards (comma separated list)\n"
292 " use '-soundhw help' to get the list of supported cards\n"
293 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL)
294 STEXI
295 @item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
296 @findex -soundhw
297 Enable audio and selected sound hardware. Use 'help' to print all
298 available sound hardware.
300 @example
301 qemu-system-i386 -soundhw sb16,adlib disk.img
302 qemu-system-i386 -soundhw es1370 disk.img
303 qemu-system-i386 -soundhw ac97 disk.img
304 qemu-system-i386 -soundhw hda disk.img
305 qemu-system-i386 -soundhw all disk.img
306 qemu-system-i386 -soundhw help
307 @end example
309 Note that Linux's i810_audio OSS kernel (for AC97) module might
310 require manually specifying clocking.
312 @example
313 modprobe i810_audio clocking=48000
314 @end example
315 ETEXI
317 DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
318 "-balloon none disable balloon device\n"
319 "-balloon virtio[,addr=str]\n"
320 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL)
321 STEXI
322 @item -balloon none
323 @findex -balloon
324 Disable balloon device.
325 @item -balloon virtio[,addr=@var{addr}]
326 Enable virtio balloon device (default), optionally with PCI address
327 @var{addr}.
328 ETEXI
330 DEF("device", HAS_ARG, QEMU_OPTION_device,
331 "-device driver[,prop[=value][,...]]\n"
332 " add device (based on driver)\n"
333 " prop=value,... sets driver properties\n"
334 " use '-device help' to print all possible drivers\n"
335 " use '-device driver,help' to print all possible properties\n",
336 QEMU_ARCH_ALL)
337 STEXI
338 @item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
339 @findex -device
340 Add device @var{driver}. @var{prop}=@var{value} sets driver
341 properties. Valid properties depend on the driver. To get help on
342 possible drivers and properties, use @code{-device help} and
343 @code{-device @var{driver},help}.
344 ETEXI
346 DEF("name", HAS_ARG, QEMU_OPTION_name,
347 "-name string1[,process=string2][,debug-threads=on|off]\n"
348 " set the name of the guest\n"
349 " string1 sets the window title and string2 the process name (on Linux)\n"
350 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n"
351 " NOTE: The thread names are for debugging and not a stable API.\n",
352 QEMU_ARCH_ALL)
353 STEXI
354 @item -name @var{name}
355 @findex -name
356 Sets the @var{name} of the guest.
357 This name will be displayed in the SDL window caption.
358 The @var{name} will also be used for the VNC server.
359 Also optionally set the top visible process name in Linux.
360 Naming of individual threads can also be enabled on Linux to aid debugging.
361 ETEXI
363 DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
364 "-uuid %08x-%04x-%04x-%04x-%012x\n"
365 " specify machine UUID\n", QEMU_ARCH_ALL)
366 STEXI
367 @item -uuid @var{uuid}
368 @findex -uuid
369 Set system UUID.
370 ETEXI
372 STEXI
373 @end table
374 ETEXI
375 DEFHEADING()
377 DEFHEADING(Block device options:)
378 STEXI
379 @table @option
380 ETEXI
382 DEF("fda", HAS_ARG, QEMU_OPTION_fda,
383 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
384 DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
385 STEXI
386 @item -fda @var{file}
387 @item -fdb @var{file}
388 @findex -fda
389 @findex -fdb
390 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can
391 use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}).
392 ETEXI
394 DEF("hda", HAS_ARG, QEMU_OPTION_hda,
395 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
396 DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
397 DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
398 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
399 DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
400 STEXI
401 @item -hda @var{file}
402 @item -hdb @var{file}
403 @item -hdc @var{file}
404 @item -hdd @var{file}
405 @findex -hda
406 @findex -hdb
407 @findex -hdc
408 @findex -hdd
409 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
410 ETEXI
412 DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
413 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
414 QEMU_ARCH_ALL)
415 STEXI
416 @item -cdrom @var{file}
417 @findex -cdrom
418 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
419 @option{-cdrom} at the same time). You can use the host CD-ROM by
420 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
421 ETEXI
423 DEF("drive", HAS_ARG, QEMU_OPTION_drive,
424 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
425 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
426 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
427 " [,serial=s][,addr=A][,rerror=ignore|stop|report]\n"
428 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n"
429 " [,readonly=on|off][,copy-on-read=on|off]\n"
430 " [,detect-zeroes=on|off|unmap]\n"
431 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n"
432 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n"
433 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n"
434 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n"
435 " [[,iops_size=is]]\n"
436 " use 'file' as a drive image\n", QEMU_ARCH_ALL)
437 STEXI
438 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
439 @findex -drive
441 Define a new drive. Valid options are:
443 @table @option
444 @item file=@var{file}
445 This option defines which disk image (@pxref{disk_images}) to use with
446 this drive. If the filename contains comma, you must double it
447 (for instance, "file=my,,file" to use file "my,file").
449 Special files such as iSCSI devices can be specified using protocol
450 specific URLs. See the section for "Device URL Syntax" for more information.
451 @item if=@var{interface}
452 This option defines on which type on interface the drive is connected.
453 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio.
454 @item bus=@var{bus},unit=@var{unit}
455 These options define where is connected the drive by defining the bus number and
456 the unit id.
457 @item index=@var{index}
458 This option defines where is connected the drive by using an index in the list
459 of available connectors of a given interface type.
460 @item media=@var{media}
461 This option defines the type of the media: disk or cdrom.
462 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
463 These options have the same definition as they have in @option{-hdachs}.
464 @item snapshot=@var{snapshot}
465 @var{snapshot} is "on" or "off" and controls snapshot mode for the given drive
466 (see @option{-snapshot}).
467 @item cache=@var{cache}
468 @var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data.
469 @item aio=@var{aio}
470 @var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
471 @item discard=@var{discard}
472 @var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls whether @dfn{discard} (also known as @dfn{trim} or @dfn{unmap}) requests are ignored or passed to the filesystem. Some machine types may not support discard requests.
473 @item format=@var{format}
474 Specify which disk @var{format} will be used rather than detecting
475 the format. Can be used to specifiy format=raw to avoid interpreting
476 an untrusted format header.
477 @item serial=@var{serial}
478 This option specifies the serial number to assign to the device.
479 @item addr=@var{addr}
480 Specify the controller's PCI address (if=virtio only).
481 @item werror=@var{action},rerror=@var{action}
482 Specify which @var{action} to take on write and read errors. Valid actions are:
483 "ignore" (ignore the error and try to continue), "stop" (pause QEMU),
484 "report" (report the error to the guest), "enospc" (pause QEMU only if the
485 host disk is full; report the error to the guest otherwise).
486 The default setting is @option{werror=enospc} and @option{rerror=report}.
487 @item readonly
488 Open drive @option{file} as read-only. Guest write attempts will fail.
489 @item copy-on-read=@var{copy-on-read}
490 @var{copy-on-read} is "on" or "off" and enables whether to copy read backing
491 file sectors into the image file.
492 @item detect-zeroes=@var{detect-zeroes}
493 @var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic
494 conversion of plain zero writes by the OS to driver specific optimized
495 zero write commands. You may even choose "unmap" if @var{discard} is set
496 to "unmap" to allow a zero write to be converted to an UNMAP operation.
497 @end table
499 By default, the @option{cache=writeback} mode is used. It will report data
500 writes as completed as soon as the data is present in the host page cache.
501 This is safe as long as your guest OS makes sure to correctly flush disk caches
502 where needed. If your guest OS does not handle volatile disk write caches
503 correctly and your host crashes or loses power, then the guest may experience
504 data corruption.
506 For such guests, you should consider using @option{cache=writethrough}. This
507 means that the host page cache will be used to read and write data, but write
508 notification will be sent to the guest only after QEMU has made sure to flush
509 each write to the disk. Be aware that this has a major impact on performance.
511 The host page cache can be avoided entirely with @option{cache=none}. This will
512 attempt to do disk IO directly to the guest's memory. QEMU may still perform
513 an internal copy of the data. Note that this is considered a writeback mode and
514 the guest OS must handle the disk write cache correctly in order to avoid data
515 corruption on host crashes.
517 The host page cache can be avoided while only sending write notifications to
518 the guest when the data has been flushed to the disk using
519 @option{cache=directsync}.
521 In case you don't care about data integrity over host failures, use
522 @option{cache=unsafe}. This option tells QEMU that it never needs to write any
523 data to the disk but can instead keep things in cache. If anything goes wrong,
524 like your host losing power, the disk storage getting disconnected accidentally,
525 etc. your image will most probably be rendered unusable. When using
526 the @option{-snapshot} option, unsafe caching is always used.
528 Copy-on-read avoids accessing the same backing file sectors repeatedly and is
529 useful when the backing file is over a slow network. By default copy-on-read
530 is off.
532 Instead of @option{-cdrom} you can use:
533 @example
534 qemu-system-i386 -drive file=file,index=2,media=cdrom
535 @end example
537 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
538 use:
539 @example
540 qemu-system-i386 -drive file=file,index=0,media=disk
541 qemu-system-i386 -drive file=file,index=1,media=disk
542 qemu-system-i386 -drive file=file,index=2,media=disk
543 qemu-system-i386 -drive file=file,index=3,media=disk
544 @end example
546 You can open an image using pre-opened file descriptors from an fd set:
547 @example
548 qemu-system-i386
549 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
550 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
551 -drive file=/dev/fdset/2,index=0,media=disk
552 @end example
554 You can connect a CDROM to the slave of ide0:
555 @example
556 qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
557 @end example
559 If you don't specify the "file=" argument, you define an empty drive:
560 @example
561 qemu-system-i386 -drive if=ide,index=1,media=cdrom
562 @end example
564 You can connect a SCSI disk with unit ID 6 on the bus #0:
565 @example
566 qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6
567 @end example
569 Instead of @option{-fda}, @option{-fdb}, you can use:
570 @example
571 qemu-system-i386 -drive file=file,index=0,if=floppy
572 qemu-system-i386 -drive file=file,index=1,if=floppy
573 @end example
575 By default, @var{interface} is "ide" and @var{index} is automatically
576 incremented:
577 @example
578 qemu-system-i386 -drive file=a -drive file=b"
579 @end example
580 is interpreted like:
581 @example
582 qemu-system-i386 -hda a -hdb b
583 @end example
584 ETEXI
586 DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
587 "-mtdblock file use 'file' as on-board Flash memory image\n",
588 QEMU_ARCH_ALL)
589 STEXI
590 @item -mtdblock @var{file}
591 @findex -mtdblock
592 Use @var{file} as on-board Flash memory image.
593 ETEXI
595 DEF("sd", HAS_ARG, QEMU_OPTION_sd,
596 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL)
597 STEXI
598 @item -sd @var{file}
599 @findex -sd
600 Use @var{file} as SecureDigital card image.
601 ETEXI
603 DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
604 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL)
605 STEXI
606 @item -pflash @var{file}
607 @findex -pflash
608 Use @var{file} as a parallel flash image.
609 ETEXI
611 DEF("snapshot", 0, QEMU_OPTION_snapshot,
612 "-snapshot write to temporary files instead of disk image files\n",
613 QEMU_ARCH_ALL)
614 STEXI
615 @item -snapshot
616 @findex -snapshot
617 Write to temporary files instead of disk image files. In this case,
618 the raw disk image you use is not written back. You can however force
619 the write back by pressing @key{C-a s} (@pxref{disk_images}).
620 ETEXI
622 DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
623 "-hdachs c,h,s[,t]\n" \
624 " force hard disk 0 physical geometry and the optional BIOS\n" \
625 " translation (t=none or lba) (usually QEMU can guess them)\n",
626 QEMU_ARCH_ALL)
627 STEXI
628 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
629 @findex -hdachs
630 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
631 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
632 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
633 all those parameters. This option is useful for old MS-DOS disk
634 images.
635 ETEXI
637 DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
638 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
639 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
640 QEMU_ARCH_ALL)
642 STEXI
644 @item -fsdev @var{fsdriver},id=@var{id},path=@var{path},[security_model=@var{security_model}][,writeout=@var{writeout}][,readonly][,socket=@var{socket}|sock_fd=@var{sock_fd}]
645 @findex -fsdev
646 Define a new file system device. Valid options are:
647 @table @option
648 @item @var{fsdriver}
649 This option specifies the fs driver backend to use.
650 Currently "local", "handle" and "proxy" file system drivers are supported.
651 @item id=@var{id}
652 Specifies identifier for this device
653 @item path=@var{path}
654 Specifies the export path for the file system device. Files under
655 this path will be available to the 9p client on the guest.
656 @item security_model=@var{security_model}
657 Specifies the security model to be used for this export path.
658 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
659 In "passthrough" security model, files are stored using the same
660 credentials as they are created on the guest. This requires QEMU
661 to run as root. In "mapped-xattr" security model, some of the file
662 attributes like uid, gid, mode bits and link target are stored as
663 file attributes. For "mapped-file" these attributes are stored in the
664 hidden .virtfs_metadata directory. Directories exported by this security model cannot
665 interact with other unix tools. "none" security model is same as
666 passthrough except the sever won't report failures if it fails to
667 set file attributes like ownership. Security model is mandatory
668 only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
669 security model as a parameter.
670 @item writeout=@var{writeout}
671 This is an optional argument. The only supported value is "immediate".
672 This means that host page cache will be used to read and write data but
673 write notification will be sent to the guest only when the data has been
674 reported as written by the storage subsystem.
675 @item readonly
676 Enables exporting 9p share as a readonly mount for guests. By default
677 read-write access is given.
678 @item socket=@var{socket}
679 Enables proxy filesystem driver to use passed socket file for communicating
680 with virtfs-proxy-helper
681 @item sock_fd=@var{sock_fd}
682 Enables proxy filesystem driver to use passed socket descriptor for
683 communicating with virtfs-proxy-helper. Usually a helper like libvirt
684 will create socketpair and pass one of the fds as sock_fd
685 @end table
687 -fsdev option is used along with -device driver "virtio-9p-pci".
688 @item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
689 Options for virtio-9p-pci driver are:
690 @table @option
691 @item fsdev=@var{id}
692 Specifies the id value specified along with -fsdev option
693 @item mount_tag=@var{mount_tag}
694 Specifies the tag name to be used by the guest to mount this export point
695 @end table
697 ETEXI
699 DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
700 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
701 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
702 QEMU_ARCH_ALL)
704 STEXI
706 @item -virtfs @var{fsdriver}[,path=@var{path}],mount_tag=@var{mount_tag}[,security_model=@var{security_model}][,writeout=@var{writeout}][,readonly][,socket=@var{socket}|sock_fd=@var{sock_fd}]
707 @findex -virtfs
709 The general form of a Virtual File system pass-through options are:
710 @table @option
711 @item @var{fsdriver}
712 This option specifies the fs driver backend to use.
713 Currently "local", "handle" and "proxy" file system drivers are supported.
714 @item id=@var{id}
715 Specifies identifier for this device
716 @item path=@var{path}
717 Specifies the export path for the file system device. Files under
718 this path will be available to the 9p client on the guest.
719 @item security_model=@var{security_model}
720 Specifies the security model to be used for this export path.
721 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
722 In "passthrough" security model, files are stored using the same
723 credentials as they are created on the guest. This requires QEMU
724 to run as root. In "mapped-xattr" security model, some of the file
725 attributes like uid, gid, mode bits and link target are stored as
726 file attributes. For "mapped-file" these attributes are stored in the
727 hidden .virtfs_metadata directory. Directories exported by this security model cannot
728 interact with other unix tools. "none" security model is same as
729 passthrough except the sever won't report failures if it fails to
730 set file attributes like ownership. Security model is mandatory only
731 for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
732 model as a parameter.
733 @item writeout=@var{writeout}
734 This is an optional argument. The only supported value is "immediate".
735 This means that host page cache will be used to read and write data but
736 write notification will be sent to the guest only when the data has been
737 reported as written by the storage subsystem.
738 @item readonly
739 Enables exporting 9p share as a readonly mount for guests. By default
740 read-write access is given.
741 @item socket=@var{socket}
742 Enables proxy filesystem driver to use passed socket file for
743 communicating with virtfs-proxy-helper. Usually a helper like libvirt
744 will create socketpair and pass one of the fds as sock_fd
745 @item sock_fd
746 Enables proxy filesystem driver to use passed 'sock_fd' as the socket
747 descriptor for interfacing with virtfs-proxy-helper
748 @end table
749 ETEXI
751 DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
752 "-virtfs_synth Create synthetic file system image\n",
753 QEMU_ARCH_ALL)
754 STEXI
755 @item -virtfs_synth
756 @findex -virtfs_synth
757 Create synthetic file system image
758 ETEXI
760 STEXI
761 @end table
762 ETEXI
763 DEFHEADING()
765 DEFHEADING(USB options:)
766 STEXI
767 @table @option
768 ETEXI
770 DEF("usb", 0, QEMU_OPTION_usb,
771 "-usb enable the USB driver (will be the default soon)\n",
772 QEMU_ARCH_ALL)
773 STEXI
774 @item -usb
775 @findex -usb
776 Enable the USB driver (will be the default soon)
777 ETEXI
779 DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
780 "-usbdevice name add the host or guest USB device 'name'\n",
781 QEMU_ARCH_ALL)
782 STEXI
784 @item -usbdevice @var{devname}
785 @findex -usbdevice
786 Add the USB device @var{devname}. @xref{usb_devices}.
788 @table @option
790 @item mouse
791 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
793 @item tablet
794 Pointer device that uses absolute coordinates (like a touchscreen). This
795 means QEMU is able to report the mouse position without having to grab the
796 mouse. Also overrides the PS/2 mouse emulation when activated.
798 @item disk:[format=@var{format}]:@var{file}
799 Mass storage device based on file. The optional @var{format} argument
800 will be used rather than detecting the format. Can be used to specifiy
801 @code{format=raw} to avoid interpreting an untrusted format header.
803 @item host:@var{bus}.@var{addr}
804 Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
806 @item host:@var{vendor_id}:@var{product_id}
807 Pass through the host device identified by @var{vendor_id}:@var{product_id}
808 (Linux only).
810 @item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
811 Serial converter to host character device @var{dev}, see @code{-serial} for the
812 available devices.
814 @item braille
815 Braille device. This will use BrlAPI to display the braille output on a real
816 or fake device.
818 @item net:@var{options}
819 Network adapter that supports CDC ethernet and RNDIS protocols.
821 @end table
822 ETEXI
824 STEXI
825 @end table
826 ETEXI
827 DEFHEADING()
829 DEFHEADING(Display options:)
830 STEXI
831 @table @option
832 ETEXI
834 DEF("display", HAS_ARG, QEMU_OPTION_display,
835 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
836 " [,window_close=on|off]|curses|none|\n"
837 " gtk[,grab_on_hover=on|off]|\n"
838 " vnc=<display>[,<optargs>]\n"
839 " select display type\n", QEMU_ARCH_ALL)
840 STEXI
841 @item -display @var{type}
842 @findex -display
843 Select type of display to use. This option is a replacement for the
844 old style -sdl/-curses/... options. Valid values for @var{type} are
845 @table @option
846 @item sdl
847 Display video output via SDL (usually in a separate graphics
848 window; see the SDL documentation for other possibilities).
849 @item curses
850 Display video output via curses. For graphics device models which
851 support a text mode, QEMU can display this output using a
852 curses/ncurses interface. Nothing is displayed when the graphics
853 device is in graphical mode or if the graphics device does not support
854 a text mode. Generally only the VGA device models support text mode.
855 @item none
856 Do not display video output. The guest will still see an emulated
857 graphics card, but its output will not be displayed to the QEMU
858 user. This option differs from the -nographic option in that it
859 only affects what is done with video output; -nographic also changes
860 the destination of the serial and parallel port data.
861 @item gtk
862 Display video output in a GTK window. This interface provides drop-down
863 menus and other UI elements to configure and control the VM during
864 runtime.
865 @item vnc
866 Start a VNC server on display <arg>
867 @end table
868 ETEXI
870 DEF("nographic", 0, QEMU_OPTION_nographic,
871 "-nographic disable graphical output and redirect serial I/Os to console\n",
872 QEMU_ARCH_ALL)
873 STEXI
874 @item -nographic
875 @findex -nographic
876 Normally, QEMU uses SDL to display the VGA output. With this option,
877 you can totally disable graphical output so that QEMU is a simple
878 command line application. The emulated serial port is redirected on
879 the console and muxed with the monitor (unless redirected elsewhere
880 explicitly). Therefore, you can still use QEMU to debug a Linux kernel
881 with a serial console. Use @key{C-a h} for help on switching between
882 the console and monitor.
883 ETEXI
885 DEF("curses", 0, QEMU_OPTION_curses,
886 "-curses use a curses/ncurses interface instead of SDL\n",
887 QEMU_ARCH_ALL)
888 STEXI
889 @item -curses
890 @findex -curses
891 Normally, QEMU uses SDL to display the VGA output. With this option,
892 QEMU can display the VGA output when in text mode using a
893 curses/ncurses interface. Nothing is displayed in graphical mode.
894 ETEXI
896 DEF("no-frame", 0, QEMU_OPTION_no_frame,
897 "-no-frame open SDL window without a frame and window decorations\n",
898 QEMU_ARCH_ALL)
899 STEXI
900 @item -no-frame
901 @findex -no-frame
902 Do not use decorations for SDL windows and start them using the whole
903 available screen space. This makes the using QEMU in a dedicated desktop
904 workspace more convenient.
905 ETEXI
907 DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
908 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
909 QEMU_ARCH_ALL)
910 STEXI
911 @item -alt-grab
912 @findex -alt-grab
913 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
914 affects the special keys (for fullscreen, monitor-mode switching, etc).
915 ETEXI
917 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
918 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
919 QEMU_ARCH_ALL)
920 STEXI
921 @item -ctrl-grab
922 @findex -ctrl-grab
923 Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
924 affects the special keys (for fullscreen, monitor-mode switching, etc).
925 ETEXI
927 DEF("no-quit", 0, QEMU_OPTION_no_quit,
928 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL)
929 STEXI
930 @item -no-quit
931 @findex -no-quit
932 Disable SDL window close capability.
933 ETEXI
935 DEF("sdl", 0, QEMU_OPTION_sdl,
936 "-sdl enable SDL\n", QEMU_ARCH_ALL)
937 STEXI
938 @item -sdl
939 @findex -sdl
940 Enable SDL.
941 ETEXI
943 DEF("spice", HAS_ARG, QEMU_OPTION_spice,
944 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
945 " [,x509-key-file=<file>][,x509-key-password=<file>]\n"
946 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
947 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6]\n"
948 " [,tls-ciphers=<list>]\n"
949 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
950 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
951 " [,sasl][,password=<secret>][,disable-ticketing]\n"
952 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
953 " [,jpeg-wan-compression=[auto|never|always]]\n"
954 " [,zlib-glz-wan-compression=[auto|never|always]]\n"
955 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
956 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
957 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
958 " enable spice\n"
959 " at least one of {port, tls-port} is mandatory\n",
960 QEMU_ARCH_ALL)
961 STEXI
962 @item -spice @var{option}[,@var{option}[,...]]
963 @findex -spice
964 Enable the spice remote desktop protocol. Valid options are
966 @table @option
968 @item port=<nr>
969 Set the TCP port spice is listening on for plaintext channels.
971 @item addr=<addr>
972 Set the IP address spice is listening on. Default is any address.
974 @item ipv4
975 @item ipv6
976 Force using the specified IP version.
978 @item password=<secret>
979 Set the password you need to authenticate.
981 @item sasl
982 Require that the client use SASL to authenticate with the spice.
983 The exact choice of authentication method used is controlled from the
984 system / user's SASL configuration file for the 'qemu' service. This
985 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
986 unprivileged user, an environment variable SASL_CONF_PATH can be used
987 to make it search alternate locations for the service config.
988 While some SASL auth methods can also provide data encryption (eg GSSAPI),
989 it is recommended that SASL always be combined with the 'tls' and
990 'x509' settings to enable use of SSL and server certificates. This
991 ensures a data encryption preventing compromise of authentication
992 credentials.
994 @item disable-ticketing
995 Allow client connects without authentication.
997 @item disable-copy-paste
998 Disable copy paste between the client and the guest.
1000 @item disable-agent-file-xfer
1001 Disable spice-vdagent based file-xfer between the client and the guest.
1003 @item tls-port=<nr>
1004 Set the TCP port spice is listening on for encrypted channels.
1006 @item x509-dir=<dir>
1007 Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1009 @item x509-key-file=<file>
1010 @item x509-key-password=<file>
1011 @item x509-cert-file=<file>
1012 @item x509-cacert-file=<file>
1013 @item x509-dh-key-file=<file>
1014 The x509 file names can also be configured individually.
1016 @item tls-ciphers=<list>
1017 Specify which ciphers to use.
1019 @item tls-channel=[main|display|cursor|inputs|record|playback]
1020 @item plaintext-channel=[main|display|cursor|inputs|record|playback]
1021 Force specific channel to be used with or without TLS encryption. The
1022 options can be specified multiple times to configure multiple
1023 channels. The special name "default" can be used to set the default
1024 mode. For channels which are not explicitly forced into one mode the
1025 spice client is allowed to pick tls/plaintext as he pleases.
1027 @item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1028 Configure image compression (lossless).
1029 Default is auto_glz.
1031 @item jpeg-wan-compression=[auto|never|always]
1032 @item zlib-glz-wan-compression=[auto|never|always]
1033 Configure wan image compression (lossy for slow links).
1034 Default is auto.
1036 @item streaming-video=[off|all|filter]
1037 Configure video stream detection. Default is filter.
1039 @item agent-mouse=[on|off]
1040 Enable/disable passing mouse events via vdagent. Default is on.
1042 @item playback-compression=[on|off]
1043 Enable/disable audio stream compression (using celt 0.5.1). Default is on.
1045 @item seamless-migration=[on|off]
1046 Enable/disable spice seamless migration. Default is off.
1048 @end table
1049 ETEXI
1051 DEF("portrait", 0, QEMU_OPTION_portrait,
1052 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
1053 QEMU_ARCH_ALL)
1054 STEXI
1055 @item -portrait
1056 @findex -portrait
1057 Rotate graphical output 90 deg left (only PXA LCD).
1058 ETEXI
1060 DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1061 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
1062 QEMU_ARCH_ALL)
1063 STEXI
1064 @item -rotate @var{deg}
1065 @findex -rotate
1066 Rotate graphical output some deg left (only PXA LCD).
1067 ETEXI
1069 DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1070 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|none]\n"
1071 " select video card type\n", QEMU_ARCH_ALL)
1072 STEXI
1073 @item -vga @var{type}
1074 @findex -vga
1075 Select type of VGA card to emulate. Valid values for @var{type} are
1076 @table @option
1077 @item cirrus
1078 Cirrus Logic GD5446 Video card. All Windows versions starting from
1079 Windows 95 should recognize and use this graphic card. For optimal
1080 performances, use 16 bit color depth in the guest and the host OS.
1081 (This one is the default)
1082 @item std
1083 Standard VGA card with Bochs VBE extensions. If your guest OS
1084 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1085 to use high resolution modes (>= 1280x1024x16) then you should use
1086 this option.
1087 @item vmware
1088 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1089 recent XFree86/XOrg server or Windows guest with a driver for this
1090 card.
1091 @item qxl
1092 QXL paravirtual graphic card. It is VGA compatible (including VESA
1093 2.0 VBE support). Works best with qxl guest drivers installed though.
1094 Recommended choice when using the spice protocol.
1095 @item tcx
1096 (sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1097 sun4m machines and offers both 8-bit and 24-bit colour depths at a
1098 fixed resolution of 1024x768.
1099 @item cg3
1100 (sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1101 for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1102 resolutions aimed at people wishing to run older Solaris versions.
1103 @item none
1104 Disable VGA card.
1105 @end table
1106 ETEXI
1108 DEF("full-screen", 0, QEMU_OPTION_full_screen,
1109 "-full-screen start in full screen\n", QEMU_ARCH_ALL)
1110 STEXI
1111 @item -full-screen
1112 @findex -full-screen
1113 Start in full screen.
1114 ETEXI
1116 DEF("g", 1, QEMU_OPTION_g ,
1117 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
1118 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1119 STEXI
1120 @item -g @var{width}x@var{height}[x@var{depth}]
1121 @findex -g
1122 Set the initial graphical resolution and depth (PPC, SPARC only).
1123 ETEXI
1125 DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1126 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL)
1127 STEXI
1128 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1129 @findex -vnc
1130 Normally, QEMU uses SDL to display the VGA output. With this option,
1131 you can have QEMU listen on VNC display @var{display} and redirect the VGA
1132 display over the VNC session. It is very useful to enable the usb
1133 tablet device when using this option (option @option{-usbdevice
1134 tablet}). When using the VNC display, you must use the @option{-k}
1135 parameter to set the keyboard layout if you are not using en-us. Valid
1136 syntax for the @var{display} is
1138 @table @option
1140 @item @var{host}:@var{d}
1142 TCP connections will only be allowed from @var{host} on display @var{d}.
1143 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1144 be omitted in which case the server will accept connections from any host.
1146 @item unix:@var{path}
1148 Connections will be allowed over UNIX domain sockets where @var{path} is the
1149 location of a unix socket to listen for connections on.
1151 @item none
1153 VNC is initialized but not started. The monitor @code{change} command
1154 can be used to later start the VNC server.
1156 @end table
1158 Following the @var{display} value there may be one or more @var{option} flags
1159 separated by commas. Valid options are
1161 @table @option
1163 @item reverse
1165 Connect to a listening VNC client via a ``reverse'' connection. The
1166 client is specified by the @var{display}. For reverse network
1167 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1168 is a TCP port number, not a display number.
1170 @item websocket
1172 Opens an additional TCP listening port dedicated to VNC Websocket connections.
1173 By definition the Websocket port is 5700+@var{display}. If @var{host} is
1174 specified connections will only be allowed from this host.
1175 As an alternative the Websocket port could be specified by using
1176 @code{websocket}=@var{port}.
1177 TLS encryption for the Websocket connection is supported if the required
1178 certificates are specified with the VNC option @option{x509}.
1180 @item password
1182 Require that password based authentication is used for client connections.
1184 The password must be set separately using the @code{set_password} command in
1185 the @ref{pcsys_monitor}. The syntax to change your password is:
1186 @code{set_password <protocol> <password>} where <protocol> could be either
1187 "vnc" or "spice".
1189 If you would like to change <protocol> password expiration, you should use
1190 @code{expire_password <protocol> <expiration-time>} where expiration time could
1191 be one of the following options: now, never, +seconds or UNIX time of
1192 expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1193 to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1194 date and time).
1196 You can also use keywords "now" or "never" for the expiration time to
1197 allow <protocol> password to expire immediately or never expire.
1199 @item tls
1201 Require that client use TLS when communicating with the VNC server. This
1202 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1203 attack. It is recommended that this option be combined with either the
1204 @option{x509} or @option{x509verify} options.
1206 @item x509=@var{/path/to/certificate/dir}
1208 Valid if @option{tls} is specified. Require that x509 credentials are used
1209 for negotiating the TLS session. The server will send its x509 certificate
1210 to the client. It is recommended that a password be set on the VNC server
1211 to provide authentication of the client when this is used. The path following
1212 this option specifies where the x509 certificates are to be loaded from.
1213 See the @ref{vnc_security} section for details on generating certificates.
1215 @item x509verify=@var{/path/to/certificate/dir}
1217 Valid if @option{tls} is specified. Require that x509 credentials are used
1218 for negotiating the TLS session. The server will send its x509 certificate
1219 to the client, and request that the client send its own x509 certificate.
1220 The server will validate the client's certificate against the CA certificate,
1221 and reject clients when validation fails. If the certificate authority is
1222 trusted, this is a sufficient authentication mechanism. You may still wish
1223 to set a password on the VNC server as a second authentication layer. The
1224 path following this option specifies where the x509 certificates are to
1225 be loaded from. See the @ref{vnc_security} section for details on generating
1226 certificates.
1228 @item sasl
1230 Require that the client use SASL to authenticate with the VNC server.
1231 The exact choice of authentication method used is controlled from the
1232 system / user's SASL configuration file for the 'qemu' service. This
1233 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1234 unprivileged user, an environment variable SASL_CONF_PATH can be used
1235 to make it search alternate locations for the service config.
1236 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1237 it is recommended that SASL always be combined with the 'tls' and
1238 'x509' settings to enable use of SSL and server certificates. This
1239 ensures a data encryption preventing compromise of authentication
1240 credentials. See the @ref{vnc_security} section for details on using
1241 SASL authentication.
1243 @item acl
1245 Turn on access control lists for checking of the x509 client certificate
1246 and SASL party. For x509 certs, the ACL check is made against the
1247 certificate's distinguished name. This is something that looks like
1248 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1249 made against the username, which depending on the SASL plugin, may
1250 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1251 When the @option{acl} flag is set, the initial access list will be
1252 empty, with a @code{deny} policy. Thus no one will be allowed to
1253 use the VNC server until the ACLs have been loaded. This can be
1254 achieved using the @code{acl} monitor command.
1256 @item lossy
1258 Enable lossy compression methods (gradient, JPEG, ...). If this
1259 option is set, VNC client may receive lossy framebuffer updates
1260 depending on its encoding settings. Enabling this option can save
1261 a lot of bandwidth at the expense of quality.
1263 @item non-adaptive
1265 Disable adaptive encodings. Adaptive encodings are enabled by default.
1266 An adaptive encoding will try to detect frequently updated screen regions,
1267 and send updates in these regions using a lossy encoding (like JPEG).
1268 This can be really helpful to save bandwidth when playing videos. Disabling
1269 adaptive encodings restores the original static behavior of encodings
1270 like Tight.
1272 @item share=[allow-exclusive|force-shared|ignore]
1274 Set display sharing policy. 'allow-exclusive' allows clients to ask
1275 for exclusive access. As suggested by the rfb spec this is
1276 implemented by dropping other connections. Connecting multiple
1277 clients in parallel requires all clients asking for a shared session
1278 (vncviewer: -shared switch). This is the default. 'force-shared'
1279 disables exclusive client access. Useful for shared desktop sessions,
1280 where you don't want someone forgetting specify -shared disconnect
1281 everybody else. 'ignore' completely ignores the shared flag and
1282 allows everybody connect unconditionally. Doesn't conform to the rfb
1283 spec but is traditional QEMU behavior.
1285 @end table
1286 ETEXI
1288 STEXI
1289 @end table
1290 ETEXI
1291 ARCHHEADING(, QEMU_ARCH_I386)
1293 ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1294 STEXI
1295 @table @option
1296 ETEXI
1298 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1299 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1300 QEMU_ARCH_I386)
1301 STEXI
1302 @item -win2k-hack
1303 @findex -win2k-hack
1304 Use it when installing Windows 2000 to avoid a disk full bug. After
1305 Windows 2000 is installed, you no longer need this option (this option
1306 slows down the IDE transfers).
1307 ETEXI
1309 HXCOMM Deprecated by -rtc
1310 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1312 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1313 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1314 QEMU_ARCH_I386)
1315 STEXI
1316 @item -no-fd-bootchk
1317 @findex -no-fd-bootchk
1318 Disable boot signature checking for floppy disks in BIOS. May
1319 be needed to boot from old floppy disks.
1320 ETEXI
1322 DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1323 "-no-acpi disable ACPI\n", QEMU_ARCH_I386)
1324 STEXI
1325 @item -no-acpi
1326 @findex -no-acpi
1327 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1328 it if your guest OS complains about ACPI problems (PC target machine
1329 only).
1330 ETEXI
1332 DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1333 "-no-hpet disable HPET\n", QEMU_ARCH_I386)
1334 STEXI
1335 @item -no-hpet
1336 @findex -no-hpet
1337 Disable HPET support.
1338 ETEXI
1340 DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1341 "-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"
1342 " ACPI table description\n", QEMU_ARCH_I386)
1343 STEXI
1344 @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}]...]
1345 @findex -acpitable
1346 Add ACPI table with specified header fields and context from specified files.
1347 For file=, take whole ACPI table from the specified files, including all
1348 ACPI headers (possible overridden by other options).
1349 For data=, only data
1350 portion of the table is used, all header information is specified in the
1351 command line.
1352 ETEXI
1354 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1355 "-smbios file=binary\n"
1356 " load SMBIOS entry from binary file\n"
1357 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d][,uefi=on|off]\n"
1358 " specify SMBIOS type 0 fields\n"
1359 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1360 " [,uuid=uuid][,sku=str][,family=str]\n"
1361 " specify SMBIOS type 1 fields\n", QEMU_ARCH_I386)
1362 STEXI
1363 @item -smbios file=@var{binary}
1364 @findex -smbios
1365 Load SMBIOS entry from binary file.
1367 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1368 Specify SMBIOS type 0 fields
1370 @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}]
1371 Specify SMBIOS type 1 fields
1372 ETEXI
1374 STEXI
1375 @end table
1376 ETEXI
1377 DEFHEADING()
1379 DEFHEADING(Network options:)
1380 STEXI
1381 @table @option
1382 ETEXI
1384 HXCOMM Legacy slirp options (now moved to -net user):
1385 #ifdef CONFIG_SLIRP
1386 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1387 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1388 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1389 #ifndef _WIN32
1390 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1391 #endif
1392 #endif
1394 DEF("net", HAS_ARG, QEMU_OPTION_net,
1395 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
1396 " create a new Network Interface Card and connect it to VLAN 'n'\n"
1397 #ifdef CONFIG_SLIRP
1398 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=on|off]\n"
1399 " [,hostname=host][,dhcpstart=addr][,dns=addr][,dnssearch=domain][,tftp=dir]\n"
1400 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1401 #ifndef _WIN32
1402 "[,smb=dir[,smbserver=addr]]\n"
1403 #endif
1404 " connect the user mode network stack to VLAN 'n', configure its\n"
1405 " DHCP server and enabled optional services\n"
1406 #endif
1407 #ifdef _WIN32
1408 "-net tap[,vlan=n][,name=str],ifname=name\n"
1409 " connect the host TAP network interface to VLAN 'n'\n"
1410 #else
1411 "-net tap[,vlan=n][,name=str][,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off][,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n"
1412 " connect the host TAP network interface to VLAN 'n'\n"
1413 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1414 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1415 " to deconfigure it\n"
1416 " use '[down]script=no' to disable script execution\n"
1417 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1418 " configure it\n"
1419 " use 'fd=h' to connect to an already opened TAP interface\n"
1420 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n"
1421 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
1422 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
1423 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1424 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1425 " use vhost=on to enable experimental in kernel accelerator\n"
1426 " (only has effect for virtio guests which use MSIX)\n"
1427 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1428 " use 'vhostfd=h' to connect to an already opened vhost net device\n"
1429 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n"
1430 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n"
1431 "-net bridge[,vlan=n][,name=str][,br=bridge][,helper=helper]\n"
1432 " connects a host TAP network interface to a host bridge device 'br'\n"
1433 " (default=" DEFAULT_BRIDGE_INTERFACE ") using the program 'helper'\n"
1434 " (default=" DEFAULT_BRIDGE_HELPER ")\n"
1435 #endif
1436 "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n"
1437 " connect the vlan 'n' to another VLAN using a socket connection\n"
1438 "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1439 " connect the vlan 'n' to multicast maddr and port\n"
1440 " use 'localaddr=addr' to specify the host address to send packets from\n"
1441 "-net socket[,vlan=n][,name=str][,fd=h][,udp=host:port][,localaddr=host:port]\n"
1442 " connect the vlan 'n' to another VLAN using an UDP tunnel\n"
1443 #ifdef CONFIG_VDE
1444 "-net vde[,vlan=n][,name=str][,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1445 " connect the vlan 'n' to port 'n' of a vde switch running\n"
1446 " on host and listening for incoming connections on 'socketpath'.\n"
1447 " Use group 'groupname' and mode 'octalmode' to change default\n"
1448 " ownership and permissions for communication port.\n"
1449 #endif
1450 #ifdef CONFIG_NETMAP
1451 "-net netmap,ifname=name[,devname=nmname]\n"
1452 " attach to the existing netmap-enabled network interface 'name', or to a\n"
1453 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n"
1454 " netmap device, defaults to '/dev/netmap')\n"
1455 #endif
1456 "-net dump[,vlan=n][,file=f][,len=n]\n"
1457 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n"
1458 "-net none use it alone to have zero network devices. If no -net option\n"
1459 " is provided, the default is '-net nic -net user'\n", QEMU_ARCH_ALL)
1460 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1461 "-netdev ["
1462 #ifdef CONFIG_SLIRP
1463 "user|"
1464 #endif
1465 "tap|"
1466 "bridge|"
1467 #ifdef CONFIG_VDE
1468 "vde|"
1469 #endif
1470 #ifdef CONFIG_NETMAP
1471 "netmap|"
1472 #endif
1473 "vhost-user|"
1474 "socket|"
1475 "hubport],id=str[,option][,option][,...]\n", QEMU_ARCH_ALL)
1476 STEXI
1477 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1478 @findex -net
1479 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1480 = 0 is the default). The NIC is an e1000 by default on the PC
1481 target. Optionally, the MAC address can be changed to @var{mac}, the
1482 device address set to @var{addr} (PCI cards only),
1483 and a @var{name} can be assigned for use in monitor commands.
1484 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1485 that the card should have; this option currently only affects virtio cards; set
1486 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1487 NIC is created. QEMU can emulate several different models of network card.
1488 Valid values for @var{type} are
1489 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1490 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1491 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1492 Not all devices are supported on all targets. Use @code{-net nic,model=help}
1493 for a list of available devices for your target.
1495 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
1496 @findex -netdev
1497 @item -net user[,@var{option}][,@var{option}][,...]
1498 Use the user mode network stack which requires no administrator
1499 privilege to run. Valid options are:
1501 @table @option
1502 @item vlan=@var{n}
1503 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1505 @item id=@var{id}
1506 @item name=@var{name}
1507 Assign symbolic name for use in monitor commands.
1509 @item net=@var{addr}[/@var{mask}]
1510 Set IP network address the guest will see. Optionally specify the netmask,
1511 either in the form a.b.c.d or as number of valid top-most bits. Default is
1512 10.0.2.0/24.
1514 @item host=@var{addr}
1515 Specify the guest-visible address of the host. Default is the 2nd IP in the
1516 guest network, i.e. x.x.x.2.
1518 @item restrict=on|off
1519 If this option is enabled, the guest will be isolated, i.e. it will not be
1520 able to contact the host and no guest IP packets will be routed over the host
1521 to the outside. This option does not affect any explicitly set forwarding rules.
1523 @item hostname=@var{name}
1524 Specifies the client hostname reported by the built-in DHCP server.
1526 @item dhcpstart=@var{addr}
1527 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1528 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1530 @item dns=@var{addr}
1531 Specify the guest-visible address of the virtual nameserver. The address must
1532 be different from the host address. Default is the 3rd IP in the guest network,
1533 i.e. x.x.x.3.
1535 @item dnssearch=@var{domain}
1536 Provides an entry for the domain-search list sent by the built-in
1537 DHCP server. More than one domain suffix can be transmitted by specifying
1538 this option multiple times. If supported, this will cause the guest to
1539 automatically try to append the given domain suffix(es) in case a domain name
1540 can not be resolved.
1542 Example:
1543 @example
1544 qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
1545 @end example
1547 @item tftp=@var{dir}
1548 When using the user mode network stack, activate a built-in TFTP
1549 server. The files in @var{dir} will be exposed as the root of a TFTP server.
1550 The TFTP client on the guest must be configured in binary mode (use the command
1551 @code{bin} of the Unix TFTP client).
1553 @item bootfile=@var{file}
1554 When using the user mode network stack, broadcast @var{file} as the BOOTP
1555 filename. In conjunction with @option{tftp}, this can be used to network boot
1556 a guest from a local directory.
1558 Example (using pxelinux):
1559 @example
1560 qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1561 @end example
1563 @item smb=@var{dir}[,smbserver=@var{addr}]
1564 When using the user mode network stack, activate a built-in SMB
1565 server so that Windows OSes can access to the host files in @file{@var{dir}}
1566 transparently. The IP address of the SMB server can be set to @var{addr}. By
1567 default the 4th IP in the guest network is used, i.e. x.x.x.4.
1569 In the guest Windows OS, the line:
1570 @example
1571 10.0.2.4 smbserver
1572 @end example
1573 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1574 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1576 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
1578 Note that a SAMBA server must be installed on the host OS.
1579 QEMU was tested successfully with smbd versions from Red Hat 9,
1580 Fedora Core 3 and OpenSUSE 11.x.
1582 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1583 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1584 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1585 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1586 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1587 be bound to a specific host interface. If no connection type is set, TCP is
1588 used. This option can be given multiple times.
1590 For example, to redirect host X11 connection from screen 1 to guest
1591 screen 0, use the following:
1593 @example
1594 # on the host
1595 qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1596 # this host xterm should open in the guest X11 server
1597 xterm -display :1
1598 @end example
1600 To redirect telnet connections from host port 5555 to telnet port on
1601 the guest, use the following:
1603 @example
1604 # on the host
1605 qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
1606 telnet localhost 5555
1607 @end example
1609 Then when you use on the host @code{telnet localhost 5555}, you
1610 connect to the guest telnet server.
1612 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1613 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
1614 Forward guest TCP connections to the IP address @var{server} on port @var{port}
1615 to the character device @var{dev} or to a program executed by @var{cmd:command}
1616 which gets spawned for each connection. This option can be given multiple times.
1618 You can either use a chardev directly and have that one used throughout QEMU's
1619 lifetime, like in the following example:
1621 @example
1622 # open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
1623 # the guest accesses it
1624 qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...]
1625 @end example
1627 Or you can execute a command on every TCP connection established by the guest,
1628 so that QEMU behaves similar to an inetd process for that virtual server:
1630 @example
1631 # call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
1632 # and connect the TCP stream to its stdin/stdout
1633 qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
1634 @end example
1636 @end table
1638 Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
1639 processed and applied to -net user. Mixing them with the new configuration
1640 syntax gives undefined results. Their use for new applications is discouraged
1641 as they will be removed from future versions.
1643 @item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1644 @item -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1645 Connect the host TAP network interface @var{name} to VLAN @var{n}.
1647 Use the network script @var{file} to configure it and the network script
1648 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
1649 automatically provides one. The default network configure script is
1650 @file{/etc/qemu-ifup} and the default network deconfigure script is
1651 @file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
1652 to disable script execution.
1654 If running QEMU as an unprivileged user, use the network helper
1655 @var{helper} to configure the TAP interface. The default network
1656 helper executable is @file{/path/to/qemu-bridge-helper}.
1658 @option{fd}=@var{h} can be used to specify the handle of an already
1659 opened host TAP interface.
1661 Examples:
1663 @example
1664 #launch a QEMU instance with the default network script
1665 qemu-system-i386 linux.img -net nic -net tap
1666 @end example
1668 @example
1669 #launch a QEMU instance with two NICs, each one connected
1670 #to a TAP device
1671 qemu-system-i386 linux.img \
1672 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
1673 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
1674 @end example
1676 @example
1677 #launch a QEMU instance with the default network helper to
1678 #connect a TAP device to bridge br0
1679 qemu-system-i386 linux.img \
1680 -net nic -net tap,"helper=/path/to/qemu-bridge-helper"
1681 @end example
1683 @item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
1684 @item -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
1685 Connect a host TAP network interface to a host bridge device.
1687 Use the network helper @var{helper} to configure the TAP interface and
1688 attach it to the bridge. The default network helper executable is
1689 @file{/path/to/qemu-bridge-helper} and the default bridge
1690 device is @file{br0}.
1692 Examples:
1694 @example
1695 #launch a QEMU instance with the default network helper to
1696 #connect a TAP device to bridge br0
1697 qemu-system-i386 linux.img -net bridge -net nic,model=virtio
1698 @end example
1700 @example
1701 #launch a QEMU instance with the default network helper to
1702 #connect a TAP device to bridge qemubr0
1703 qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
1704 @end example
1706 @item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1707 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1709 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
1710 machine using a TCP socket connection. If @option{listen} is
1711 specified, QEMU waits for incoming connections on @var{port}
1712 (@var{host} is optional). @option{connect} is used to connect to
1713 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
1714 specifies an already opened TCP socket.
1716 Example:
1717 @example
1718 # launch a first QEMU instance
1719 qemu-system-i386 linux.img \
1720 -net nic,macaddr=52:54:00:12:34:56 \
1721 -net socket,listen=:1234
1722 # connect the VLAN 0 of this instance to the VLAN 0
1723 # of the first instance
1724 qemu-system-i386 linux.img \
1725 -net nic,macaddr=52:54:00:12:34:57 \
1726 -net socket,connect=127.0.0.1:1234
1727 @end example
1729 @item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1730 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1732 Create a VLAN @var{n} shared with another QEMU virtual
1733 machines using a UDP multicast socket, effectively making a bus for
1734 every QEMU with same multicast address @var{maddr} and @var{port}.
1735 NOTES:
1736 @enumerate
1737 @item
1738 Several QEMU can be running on different hosts and share same bus (assuming
1739 correct multicast setup for these hosts).
1740 @item
1741 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
1742 @url{http://user-mode-linux.sf.net}.
1743 @item
1744 Use @option{fd=h} to specify an already opened UDP multicast socket.
1745 @end enumerate
1747 Example:
1748 @example
1749 # launch one QEMU instance
1750 qemu-system-i386 linux.img \
1751 -net nic,macaddr=52:54:00:12:34:56 \
1752 -net socket,mcast=230.0.0.1:1234
1753 # launch another QEMU instance on same "bus"
1754 qemu-system-i386 linux.img \
1755 -net nic,macaddr=52:54:00:12:34:57 \
1756 -net socket,mcast=230.0.0.1:1234
1757 # launch yet another QEMU instance on same "bus"
1758 qemu-system-i386 linux.img \
1759 -net nic,macaddr=52:54:00:12:34:58 \
1760 -net socket,mcast=230.0.0.1:1234
1761 @end example
1763 Example (User Mode Linux compat.):
1764 @example
1765 # launch QEMU instance (note mcast address selected
1766 # is UML's default)
1767 qemu-system-i386 linux.img \
1768 -net nic,macaddr=52:54:00:12:34:56 \
1769 -net socket,mcast=239.192.168.1:1102
1770 # launch UML
1771 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
1772 @end example
1774 Example (send packets from host's 1.2.3.4):
1775 @example
1776 qemu-system-i386 linux.img \
1777 -net nic,macaddr=52:54:00:12:34:56 \
1778 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
1779 @end example
1781 @item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1782 @item -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1783 Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
1784 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
1785 and MODE @var{octalmode} to change default ownership and permissions for
1786 communication port. This option is only available if QEMU has been compiled
1787 with vde support enabled.
1789 Example:
1790 @example
1791 # launch vde switch
1792 vde_switch -F -sock /tmp/myswitch
1793 # launch QEMU instance
1794 qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch
1795 @end example
1797 @item -netdev hubport,id=@var{id},hubid=@var{hubid}
1799 Create a hub port on QEMU "vlan" @var{hubid}.
1801 The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single
1802 netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the
1803 required hub automatically.
1805 @item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off]
1807 Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should
1808 be a unix domain socket backed one. The vhost-user uses a specifically defined
1809 protocol to pass vhost ioctl replacement messages to an application on the other
1810 end of the socket. On non-MSIX guests, the feature can be forced with
1811 @var{vhostforce}.
1813 Example:
1814 @example
1815 qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \
1816 -numa node,memdev=mem \
1817 -chardev socket,path=/path/to/socket \
1818 -netdev type=vhost-user,id=net0,chardev=chr0 \
1819 -device virtio-net-pci,netdev=net0
1820 @end example
1822 @item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
1823 Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
1824 At most @var{len} bytes (64k by default) per packet are stored. The file format is
1825 libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
1827 @item -net none
1828 Indicate that no network devices should be configured. It is used to
1829 override the default configuration (@option{-net nic -net user}) which
1830 is activated if no @option{-net} options are provided.
1831 ETEXI
1833 STEXI
1834 @end table
1835 ETEXI
1836 DEFHEADING()
1838 DEFHEADING(Character device options:)
1839 STEXI
1841 The general form of a character device option is:
1842 @table @option
1843 ETEXI
1845 DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
1846 "-chardev null,id=id[,mux=on|off]\n"
1847 "-chardev socket,id=id[,host=host],port=host[,to=to][,ipv4][,ipv6][,nodelay]\n"
1848 " [,server][,nowait][,telnet][,mux=on|off] (tcp)\n"
1849 "-chardev socket,id=id,path=path[,server][,nowait][,telnet],[mux=on|off] (unix)\n"
1850 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
1851 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
1852 "-chardev msmouse,id=id[,mux=on|off]\n"
1853 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
1854 " [,mux=on|off]\n"
1855 "-chardev ringbuf,id=id[,size=size]\n"
1856 "-chardev file,id=id,path=path[,mux=on|off]\n"
1857 "-chardev pipe,id=id,path=path[,mux=on|off]\n"
1858 #ifdef _WIN32
1859 "-chardev console,id=id[,mux=on|off]\n"
1860 "-chardev serial,id=id,path=path[,mux=on|off]\n"
1861 #else
1862 "-chardev pty,id=id[,mux=on|off]\n"
1863 "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n"
1864 #endif
1865 #ifdef CONFIG_BRLAPI
1866 "-chardev braille,id=id[,mux=on|off]\n"
1867 #endif
1868 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
1869 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
1870 "-chardev serial,id=id,path=path[,mux=on|off]\n"
1871 "-chardev tty,id=id,path=path[,mux=on|off]\n"
1872 #endif
1873 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
1874 "-chardev parallel,id=id,path=path[,mux=on|off]\n"
1875 "-chardev parport,id=id,path=path[,mux=on|off]\n"
1876 #endif
1877 #if defined(CONFIG_SPICE)
1878 "-chardev spicevmc,id=id,name=name[,debug=debug]\n"
1879 "-chardev spiceport,id=id,name=name[,debug=debug]\n"
1880 #endif
1881 , QEMU_ARCH_ALL
1884 STEXI
1885 @item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
1886 @findex -chardev
1887 Backend is one of:
1888 @option{null},
1889 @option{socket},
1890 @option{udp},
1891 @option{msmouse},
1892 @option{vc},
1893 @option{ringbuf},
1894 @option{file},
1895 @option{pipe},
1896 @option{console},
1897 @option{serial},
1898 @option{pty},
1899 @option{stdio},
1900 @option{braille},
1901 @option{tty},
1902 @option{parallel},
1903 @option{parport},
1904 @option{spicevmc}.
1905 @option{spiceport}.
1906 The specific backend will determine the applicable options.
1908 All devices must have an id, which can be any string up to 127 characters long.
1909 It is used to uniquely identify this device in other command line directives.
1911 A character device may be used in multiplexing mode by multiple front-ends.
1912 The key sequence of @key{Control-a} and @key{c} will rotate the input focus
1913 between attached front-ends. Specify @option{mux=on} to enable this mode.
1915 Options to each backend are described below.
1917 @item -chardev null ,id=@var{id}
1918 A void device. This device will not emit any data, and will drop any data it
1919 receives. The null backend does not take any options.
1921 @item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet]
1923 Create a two-way stream socket, which can be either a TCP or a unix socket. A
1924 unix socket will be created if @option{path} is specified. Behaviour is
1925 undefined if TCP options are specified for a unix socket.
1927 @option{server} specifies that the socket shall be a listening socket.
1929 @option{nowait} specifies that QEMU should not block waiting for a client to
1930 connect to a listening socket.
1932 @option{telnet} specifies that traffic on the socket should interpret telnet
1933 escape sequences.
1935 TCP and unix socket options are given below:
1937 @table @option
1939 @item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
1941 @option{host} for a listening socket specifies the local address to be bound.
1942 For a connecting socket species the remote host to connect to. @option{host} is
1943 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
1945 @option{port} for a listening socket specifies the local port to be bound. For a
1946 connecting socket specifies the port on the remote host to connect to.
1947 @option{port} can be given as either a port number or a service name.
1948 @option{port} is required.
1950 @option{to} is only relevant to listening sockets. If it is specified, and
1951 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
1952 to and including @option{to} until it succeeds. @option{to} must be specified
1953 as a port number.
1955 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1956 If neither is specified the socket may use either protocol.
1958 @option{nodelay} disables the Nagle algorithm.
1960 @item unix options: path=@var{path}
1962 @option{path} specifies the local path of the unix socket. @option{path} is
1963 required.
1965 @end table
1967 @item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
1969 Sends all traffic from the guest to a remote host over UDP.
1971 @option{host} specifies the remote host to connect to. If not specified it
1972 defaults to @code{localhost}.
1974 @option{port} specifies the port on the remote host to connect to. @option{port}
1975 is required.
1977 @option{localaddr} specifies the local address to bind to. If not specified it
1978 defaults to @code{0.0.0.0}.
1980 @option{localport} specifies the local port to bind to. If not specified any
1981 available local port will be used.
1983 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1984 If neither is specified the device may use either protocol.
1986 @item -chardev msmouse ,id=@var{id}
1988 Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
1989 take any options.
1991 @item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
1993 Connect to a QEMU text console. @option{vc} may optionally be given a specific
1994 size.
1996 @option{width} and @option{height} specify the width and height respectively of
1997 the console, in pixels.
1999 @option{cols} and @option{rows} specify that the console be sized to fit a text
2000 console with the given dimensions.
2002 @item -chardev ringbuf ,id=@var{id} [,size=@var{size}]
2004 Create a ring buffer with fixed size @option{size}.
2005 @var{size} must be a power of two, and defaults to @code{64K}).
2007 @item -chardev file ,id=@var{id} ,path=@var{path}
2009 Log all traffic received from the guest to a file.
2011 @option{path} specifies the path of the file to be opened. This file will be
2012 created if it does not already exist, and overwritten if it does. @option{path}
2013 is required.
2015 @item -chardev pipe ,id=@var{id} ,path=@var{path}
2017 Create a two-way connection to the guest. The behaviour differs slightly between
2018 Windows hosts and other hosts:
2020 On Windows, a single duplex pipe will be created at
2021 @file{\\.pipe\@option{path}}.
2023 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
2024 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
2025 received by the guest. Data written by the guest can be read from
2026 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
2027 be present.
2029 @option{path} forms part of the pipe path as described above. @option{path} is
2030 required.
2032 @item -chardev console ,id=@var{id}
2034 Send traffic from the guest to QEMU's standard output. @option{console} does not
2035 take any options.
2037 @option{console} is only available on Windows hosts.
2039 @item -chardev serial ,id=@var{id} ,path=@option{path}
2041 Send traffic from the guest to a serial device on the host.
2043 On Unix hosts serial will actually accept any tty device,
2044 not only serial lines.
2046 @option{path} specifies the name of the serial device to open.
2048 @item -chardev pty ,id=@var{id}
2050 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2051 not take any options.
2053 @option{pty} is not available on Windows hosts.
2055 @item -chardev stdio ,id=@var{id} [,signal=on|off]
2056 Connect to standard input and standard output of the QEMU process.
2058 @option{signal} controls if signals are enabled on the terminal, that includes
2059 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2060 default, use @option{signal=off} to disable it.
2062 @option{stdio} is not available on Windows hosts.
2064 @item -chardev braille ,id=@var{id}
2066 Connect to a local BrlAPI server. @option{braille} does not take any options.
2068 @item -chardev tty ,id=@var{id} ,path=@var{path}
2070 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2071 DragonFlyBSD hosts. It is an alias for @option{serial}.
2073 @option{path} specifies the path to the tty. @option{path} is required.
2075 @item -chardev parallel ,id=@var{id} ,path=@var{path}
2076 @item -chardev parport ,id=@var{id} ,path=@var{path}
2078 @option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2080 Connect to a local parallel port.
2082 @option{path} specifies the path to the parallel port device. @option{path} is
2083 required.
2085 @item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2087 @option{spicevmc} is only available when spice support is built in.
2089 @option{debug} debug level for spicevmc
2091 @option{name} name of spice channel to connect to
2093 Connect to a spice virtual machine channel, such as vdiport.
2095 @item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2097 @option{spiceport} is only available when spice support is built in.
2099 @option{debug} debug level for spicevmc
2101 @option{name} name of spice port to connect to
2103 Connect to a spice port, allowing a Spice client to handle the traffic
2104 identified by a name (preferably a fqdn).
2105 ETEXI
2107 STEXI
2108 @end table
2109 ETEXI
2110 DEFHEADING()
2112 DEFHEADING(Device URL Syntax:)
2113 STEXI
2115 In addition to using normal file images for the emulated storage devices,
2116 QEMU can also use networked resources such as iSCSI devices. These are
2117 specified using a special URL syntax.
2119 @table @option
2120 @item iSCSI
2121 iSCSI support allows QEMU to access iSCSI resources directly and use as
2122 images for the guest storage. Both disk and cdrom images are supported.
2124 Syntax for specifying iSCSI LUNs is
2125 ``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
2127 By default qemu will use the iSCSI initiator-name
2128 'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command
2129 line or a configuration file.
2132 Example (without authentication):
2133 @example
2134 qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
2135 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
2136 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2137 @end example
2139 Example (CHAP username/password via URL):
2140 @example
2141 qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
2142 @end example
2144 Example (CHAP username/password via environment variables):
2145 @example
2146 LIBISCSI_CHAP_USERNAME="user" \
2147 LIBISCSI_CHAP_PASSWORD="password" \
2148 qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2149 @end example
2151 iSCSI support is an optional feature of QEMU and only available when
2152 compiled and linked against libiscsi.
2153 ETEXI
2154 DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
2155 "-iscsi [user=user][,password=password]\n"
2156 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
2157 " [,initiator-name=initiator-iqn][,id=target-iqn]\n"
2158 " iSCSI session parameters\n", QEMU_ARCH_ALL)
2159 STEXI
2161 iSCSI parameters such as username and password can also be specified via
2162 a configuration file. See qemu-doc for more information and examples.
2164 @item NBD
2165 QEMU supports NBD (Network Block Devices) both using TCP protocol as well
2166 as Unix Domain Sockets.
2168 Syntax for specifying a NBD device using TCP
2169 ``nbd:<server-ip>:<port>[:exportname=<export>]''
2171 Syntax for specifying a NBD device using Unix Domain Sockets
2172 ``nbd:unix:<domain-socket>[:exportname=<export>]''
2175 Example for TCP
2176 @example
2177 qemu-system-i386 --drive file=nbd:192.0.2.1:30000
2178 @end example
2180 Example for Unix Domain Sockets
2181 @example
2182 qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket
2183 @end example
2185 @item SSH
2186 QEMU supports SSH (Secure Shell) access to remote disks.
2188 Examples:
2189 @example
2190 qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img
2191 qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img
2192 @end example
2194 Currently authentication must be done using ssh-agent. Other
2195 authentication methods may be supported in future.
2197 @item Sheepdog
2198 Sheepdog is a distributed storage system for QEMU.
2199 QEMU supports using either local sheepdog devices or remote networked
2200 devices.
2202 Syntax for specifying a sheepdog device
2203 @example
2204 sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag]
2205 @end example
2207 Example
2208 @example
2209 qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine
2210 @end example
2212 See also @url{http://http://www.osrg.net/sheepdog/}.
2214 @item GlusterFS
2215 GlusterFS is an user space distributed file system.
2216 QEMU supports the use of GlusterFS volumes for hosting VM disk images using
2217 TCP, Unix Domain Sockets and RDMA transport protocols.
2219 Syntax for specifying a VM disk image on GlusterFS volume is
2220 @example
2221 gluster[+transport]://[server[:port]]/volname/image[?socket=...]
2222 @end example
2225 Example
2226 @example
2227 qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img
2228 @end example
2230 See also @url{http://www.gluster.org}.
2232 @item HTTP/HTTPS/FTP/FTPS/TFTP
2233 QEMU supports read-only access to files accessed over http(s), ftp(s) and tftp.
2235 Syntax using a single filename:
2236 @example
2237 <protocol>://[<username>[:<password>]@@]<host>/<path>
2238 @end example
2240 where:
2241 @table @option
2242 @item protocol
2243 'http', 'https', 'ftp', 'ftps', or 'tftp'.
2245 @item username
2246 Optional username for authentication to the remote server.
2248 @item password
2249 Optional password for authentication to the remote server.
2251 @item host
2252 Address of the remote server.
2254 @item path
2255 Path on the remote server, including any query string.
2256 @end table
2258 The following options are also supported:
2259 @table @option
2260 @item url
2261 The full URL when passing options to the driver explicitly.
2263 @item readahead
2264 The amount of data to read ahead with each range request to the remote server.
2265 This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it
2266 does not have a suffix, it will be assumed to be in bytes. The value must be a
2267 multiple of 512 bytes. It defaults to 256k.
2269 @item sslverify
2270 Whether to verify the remote server's certificate when connecting over SSL. It
2271 can have the value 'on' or 'off'. It defaults to 'on'.
2272 @end table
2274 Note that when passing options to qemu explicitly, @option{driver} is the value
2275 of <protocol>.
2277 Example: boot from a remote Fedora 20 live ISO image
2278 @example
2279 qemu-system-x86_64 --drive media=cdrom,file=http://dl.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
2281 qemu-system-x86_64 --drive media=cdrom,file.driver=http,file.url=http://dl.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
2282 @end example
2284 Example: boot from a remote Fedora 20 cloud image using a local overlay for
2285 writes, copy-on-read, and a readahead of 64k
2286 @example
2287 qemu-img create -f qcow2 -o backing_file='json:@{"file.driver":"http",, "file.url":"https://dl.fedoraproject.org/pub/fedora/linux/releases/20/Images/x86_64/Fedora-x86_64-20-20131211.1-sda.qcow2",, "file.readahead":"64k"@}' /tmp/Fedora-x86_64-20-20131211.1-sda.qcow2
2289 qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on
2290 @end example
2292 Example: boot from an image stored on a VMware vSphere server with a self-signed
2293 certificate using a local overlay for writes and a readahead of 64k
2294 @example
2295 qemu-img create -f qcow2 -o backing_file='json:@{"file.driver":"https",, "file.url":"https://user:password@@vsphere.example.com/folder/test/test-flat.vmdk?dcPath=Datacenter&dsName=datastore1",, "file.sslverify":"off",, "file.readahead":"64k"@}' /tmp/test.qcow2
2297 qemu-system-x86_64 -drive file=/tmp/test.qcow2
2298 @end example
2299 ETEXI
2301 STEXI
2302 @end table
2303 ETEXI
2305 DEFHEADING(Bluetooth(R) options:)
2306 STEXI
2307 @table @option
2308 ETEXI
2310 DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
2311 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \
2312 "-bt hci,host[:id]\n" \
2313 " use host's HCI with the given name\n" \
2314 "-bt hci[,vlan=n]\n" \
2315 " emulate a standard HCI in virtual scatternet 'n'\n" \
2316 "-bt vhci[,vlan=n]\n" \
2317 " add host computer to virtual scatternet 'n' using VHCI\n" \
2318 "-bt device:dev[,vlan=n]\n" \
2319 " emulate a bluetooth device 'dev' in scatternet 'n'\n",
2320 QEMU_ARCH_ALL)
2321 STEXI
2322 @item -bt hci[...]
2323 @findex -bt
2324 Defines the function of the corresponding Bluetooth HCI. -bt options
2325 are matched with the HCIs present in the chosen machine type. For
2326 example when emulating a machine with only one HCI built into it, only
2327 the first @code{-bt hci[...]} option is valid and defines the HCI's
2328 logic. The Transport Layer is decided by the machine type. Currently
2329 the machines @code{n800} and @code{n810} have one HCI and all other
2330 machines have none.
2332 @anchor{bt-hcis}
2333 The following three types are recognized:
2335 @table @option
2336 @item -bt hci,null
2337 (default) The corresponding Bluetooth HCI assumes no internal logic
2338 and will not respond to any HCI commands or emit events.
2340 @item -bt hci,host[:@var{id}]
2341 (@code{bluez} only) The corresponding HCI passes commands / events
2342 to / from the physical HCI identified by the name @var{id} (default:
2343 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
2344 capable systems like Linux.
2346 @item -bt hci[,vlan=@var{n}]
2347 Add a virtual, standard HCI that will participate in the Bluetooth
2348 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
2349 VLANs, devices inside a bluetooth network @var{n} can only communicate
2350 with other devices in the same network (scatternet).
2351 @end table
2353 @item -bt vhci[,vlan=@var{n}]
2354 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2355 to the host bluetooth stack instead of to the emulated target. This
2356 allows the host and target machines to participate in a common scatternet
2357 and communicate. Requires the Linux @code{vhci} driver installed. Can
2358 be used as following:
2360 @example
2361 qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2362 @end example
2364 @item -bt device:@var{dev}[,vlan=@var{n}]
2365 Emulate a bluetooth device @var{dev} and place it in network @var{n}
2366 (default @code{0}). QEMU can only emulate one type of bluetooth devices
2367 currently:
2369 @table @option
2370 @item keyboard
2371 Virtual wireless keyboard implementing the HIDP bluetooth profile.
2372 @end table
2373 ETEXI
2375 STEXI
2376 @end table
2377 ETEXI
2378 DEFHEADING()
2380 #ifdef CONFIG_TPM
2381 DEFHEADING(TPM device options:)
2383 DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
2384 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
2385 " use path to provide path to a character device; default is /dev/tpm0\n"
2386 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
2387 " not provided it will be searched for in /sys/class/misc/tpm?/device\n",
2388 QEMU_ARCH_ALL)
2389 STEXI
2391 The general form of a TPM device option is:
2392 @table @option
2394 @item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
2395 @findex -tpmdev
2396 Backend type must be:
2397 @option{passthrough}.
2399 The specific backend type will determine the applicable options.
2400 The @code{-tpmdev} option creates the TPM backend and requires a
2401 @code{-device} option that specifies the TPM frontend interface model.
2403 Options to each backend are described below.
2405 Use 'help' to print all available TPM backend types.
2406 @example
2407 qemu -tpmdev help
2408 @end example
2410 @item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path}
2412 (Linux-host only) Enable access to the host's TPM using the passthrough
2413 driver.
2415 @option{path} specifies the path to the host's TPM device, i.e., on
2416 a Linux host this would be @code{/dev/tpm0}.
2417 @option{path} is optional and by default @code{/dev/tpm0} is used.
2419 @option{cancel-path} specifies the path to the host TPM device's sysfs
2420 entry allowing for cancellation of an ongoing TPM command.
2421 @option{cancel-path} is optional and by default QEMU will search for the
2422 sysfs entry to use.
2424 Some notes about using the host's TPM with the passthrough driver:
2426 The TPM device accessed by the passthrough driver must not be
2427 used by any other application on the host.
2429 Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
2430 the VM's firmware (BIOS/UEFI) will not be able to initialize the
2431 TPM again and may therefore not show a TPM-specific menu that would
2432 otherwise allow the user to configure the TPM, e.g., allow the user to
2433 enable/disable or activate/deactivate the TPM.
2434 Further, if TPM ownership is released from within a VM then the host's TPM
2435 will get disabled and deactivated. To enable and activate the
2436 TPM again afterwards, the host has to be rebooted and the user is
2437 required to enter the firmware's menu to enable and activate the TPM.
2438 If the TPM is left disabled and/or deactivated most TPM commands will fail.
2440 To create a passthrough TPM use the following two options:
2441 @example
2442 -tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
2443 @end example
2444 Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
2445 @code{tpmdev=tpm0} in the device option.
2447 @end table
2449 ETEXI
2451 DEFHEADING()
2453 #endif
2455 DEFHEADING(Linux/Multiboot boot specific:)
2456 STEXI
2458 When using these options, you can use a given Linux or Multiboot
2459 kernel without installing it in the disk image. It can be useful
2460 for easier testing of various kernels.
2462 @table @option
2463 ETEXI
2465 DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
2466 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL)
2467 STEXI
2468 @item -kernel @var{bzImage}
2469 @findex -kernel
2470 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2471 or in multiboot format.
2472 ETEXI
2474 DEF("append", HAS_ARG, QEMU_OPTION_append, \
2475 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL)
2476 STEXI
2477 @item -append @var{cmdline}
2478 @findex -append
2479 Use @var{cmdline} as kernel command line
2480 ETEXI
2482 DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
2483 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL)
2484 STEXI
2485 @item -initrd @var{file}
2486 @findex -initrd
2487 Use @var{file} as initial ram disk.
2489 @item -initrd "@var{file1} arg=foo,@var{file2}"
2491 This syntax is only available with multiboot.
2493 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
2494 first module.
2495 ETEXI
2497 DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
2498 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL)
2499 STEXI
2500 @item -dtb @var{file}
2501 @findex -dtb
2502 Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
2503 on boot.
2504 ETEXI
2506 STEXI
2507 @end table
2508 ETEXI
2509 DEFHEADING()
2511 DEFHEADING(Debug/Expert options:)
2512 STEXI
2513 @table @option
2514 ETEXI
2516 DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
2517 "-serial dev redirect the serial port to char device 'dev'\n",
2518 QEMU_ARCH_ALL)
2519 STEXI
2520 @item -serial @var{dev}
2521 @findex -serial
2522 Redirect the virtual serial port to host character device
2523 @var{dev}. The default device is @code{vc} in graphical mode and
2524 @code{stdio} in non graphical mode.
2526 This option can be used several times to simulate up to 4 serial
2527 ports.
2529 Use @code{-serial none} to disable all serial ports.
2531 Available character devices are:
2532 @table @option
2533 @item vc[:@var{W}x@var{H}]
2534 Virtual console. Optionally, a width and height can be given in pixel with
2535 @example
2536 vc:800x600
2537 @end example
2538 It is also possible to specify width or height in characters:
2539 @example
2540 vc:80Cx24C
2541 @end example
2542 @item pty
2543 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
2544 @item none
2545 No device is allocated.
2546 @item null
2547 void device
2548 @item chardev:@var{id}
2549 Use a named character device defined with the @code{-chardev} option.
2550 @item /dev/XXX
2551 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
2552 parameters are set according to the emulated ones.
2553 @item /dev/parport@var{N}
2554 [Linux only, parallel port only] Use host parallel port
2555 @var{N}. Currently SPP and EPP parallel port features can be used.
2556 @item file:@var{filename}
2557 Write output to @var{filename}. No character can be read.
2558 @item stdio
2559 [Unix only] standard input/output
2560 @item pipe:@var{filename}
2561 name pipe @var{filename}
2562 @item COM@var{n}
2563 [Windows only] Use host serial port @var{n}
2564 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
2565 This implements UDP Net Console.
2566 When @var{remote_host} or @var{src_ip} are not specified
2567 they default to @code{0.0.0.0}.
2568 When not using a specified @var{src_port} a random port is automatically chosen.
2570 If you just want a simple readonly console you can use @code{netcat} or
2571 @code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
2572 @code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
2573 will appear in the netconsole session.
2575 If you plan to send characters back via netconsole or you want to stop
2576 and start QEMU a lot of times, you should have QEMU use the same
2577 source port each time by using something like @code{-serial
2578 udp::4555@@:4556} to QEMU. Another approach is to use a patched
2579 version of netcat which can listen to a TCP port and send and receive
2580 characters via udp. If you have a patched version of netcat which
2581 activates telnet remote echo and single char transfer, then you can
2582 use the following options to step up a netcat redirector to allow
2583 telnet on port 5555 to access the QEMU port.
2584 @table @code
2585 @item QEMU Options:
2586 -serial udp::4555@@:4556
2587 @item netcat options:
2588 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
2589 @item telnet options:
2590 localhost 5555
2591 @end table
2593 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay]
2594 The TCP Net Console has two modes of operation. It can send the serial
2595 I/O to a location or wait for a connection from a location. By default
2596 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
2597 the @var{server} option QEMU will wait for a client socket application
2598 to connect to the port before continuing, unless the @code{nowait}
2599 option was specified. The @code{nodelay} option disables the Nagle buffering
2600 algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only
2601 one TCP connection at a time is accepted. You can use @code{telnet} to
2602 connect to the corresponding character device.
2603 @table @code
2604 @item Example to send tcp console to 192.168.0.2 port 4444
2605 -serial tcp:192.168.0.2:4444
2606 @item Example to listen and wait on port 4444 for connection
2607 -serial tcp::4444,server
2608 @item Example to not wait and listen on ip 192.168.0.100 port 4444
2609 -serial tcp:192.168.0.100:4444,server,nowait
2610 @end table
2612 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
2613 The telnet protocol is used instead of raw tcp sockets. The options
2614 work the same as if you had specified @code{-serial tcp}. The
2615 difference is that the port acts like a telnet server or client using
2616 telnet option negotiation. This will also allow you to send the
2617 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
2618 sequence. Typically in unix telnet you do it with Control-] and then
2619 type "send break" followed by pressing the enter key.
2621 @item unix:@var{path}[,server][,nowait]
2622 A unix domain socket is used instead of a tcp socket. The option works the
2623 same as if you had specified @code{-serial tcp} except the unix domain socket
2624 @var{path} is used for connections.
2626 @item mon:@var{dev_string}
2627 This is a special option to allow the monitor to be multiplexed onto
2628 another serial port. The monitor is accessed with key sequence of
2629 @key{Control-a} and then pressing @key{c}.
2630 @var{dev_string} should be any one of the serial devices specified
2631 above. An example to multiplex the monitor onto a telnet server
2632 listening on port 4444 would be:
2633 @table @code
2634 @item -serial mon:telnet::4444,server,nowait
2635 @end table
2636 When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
2637 QEMU any more but will be passed to the guest instead.
2639 @item braille
2640 Braille device. This will use BrlAPI to display the braille output on a real
2641 or fake device.
2643 @item msmouse
2644 Three button serial mouse. Configure the guest to use Microsoft protocol.
2645 @end table
2646 ETEXI
2648 DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
2649 "-parallel dev redirect the parallel port to char device 'dev'\n",
2650 QEMU_ARCH_ALL)
2651 STEXI
2652 @item -parallel @var{dev}
2653 @findex -parallel
2654 Redirect the virtual parallel port to host device @var{dev} (same
2655 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
2656 be used to use hardware devices connected on the corresponding host
2657 parallel port.
2659 This option can be used several times to simulate up to 3 parallel
2660 ports.
2662 Use @code{-parallel none} to disable all parallel ports.
2663 ETEXI
2665 DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
2666 "-monitor dev redirect the monitor to char device 'dev'\n",
2667 QEMU_ARCH_ALL)
2668 STEXI
2669 @item -monitor @var{dev}
2670 @findex -monitor
2671 Redirect the monitor to host device @var{dev} (same devices as the
2672 serial port).
2673 The default device is @code{vc} in graphical mode and @code{stdio} in
2674 non graphical mode.
2675 Use @code{-monitor none} to disable the default monitor.
2676 ETEXI
2677 DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
2678 "-qmp dev like -monitor but opens in 'control' mode\n",
2679 QEMU_ARCH_ALL)
2680 STEXI
2681 @item -qmp @var{dev}
2682 @findex -qmp
2683 Like -monitor but opens in 'control' mode.
2684 ETEXI
2686 DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
2687 "-mon [chardev=]name[,mode=readline|control][,default]\n", QEMU_ARCH_ALL)
2688 STEXI
2689 @item -mon [chardev=]name[,mode=readline|control][,default]
2690 @findex -mon
2691 Setup monitor on chardev @var{name}.
2692 ETEXI
2694 DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
2695 "-debugcon dev redirect the debug console to char device 'dev'\n",
2696 QEMU_ARCH_ALL)
2697 STEXI
2698 @item -debugcon @var{dev}
2699 @findex -debugcon
2700 Redirect the debug console to host device @var{dev} (same devices as the
2701 serial port). The debug console is an I/O port which is typically port
2702 0xe9; writing to that I/O port sends output to this device.
2703 The default device is @code{vc} in graphical mode and @code{stdio} in
2704 non graphical mode.
2705 ETEXI
2707 DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
2708 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL)
2709 STEXI
2710 @item -pidfile @var{file}
2711 @findex -pidfile
2712 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
2713 from a script.
2714 ETEXI
2716 DEF("singlestep", 0, QEMU_OPTION_singlestep, \
2717 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL)
2718 STEXI
2719 @item -singlestep
2720 @findex -singlestep
2721 Run the emulation in single step mode.
2722 ETEXI
2724 DEF("S", 0, QEMU_OPTION_S, \
2725 "-S freeze CPU at startup (use 'c' to start execution)\n",
2726 QEMU_ARCH_ALL)
2727 STEXI
2728 @item -S
2729 @findex -S
2730 Do not start CPU at startup (you must type 'c' in the monitor).
2731 ETEXI
2733 DEF("realtime", HAS_ARG, QEMU_OPTION_realtime,
2734 "-realtime [mlock=on|off]\n"
2735 " run qemu with realtime features\n"
2736 " mlock=on|off controls mlock support (default: on)\n",
2737 QEMU_ARCH_ALL)
2738 STEXI
2739 @item -realtime mlock=on|off
2740 @findex -realtime
2741 Run qemu with realtime features.
2742 mlocking qemu and guest memory can be enabled via @option{mlock=on}
2743 (enabled by default).
2744 ETEXI
2746 DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
2747 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL)
2748 STEXI
2749 @item -gdb @var{dev}
2750 @findex -gdb
2751 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
2752 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
2753 stdio are reasonable use case. The latter is allowing to start QEMU from
2754 within gdb and establish the connection via a pipe:
2755 @example
2756 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
2757 @end example
2758 ETEXI
2760 DEF("s", 0, QEMU_OPTION_s, \
2761 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
2762 QEMU_ARCH_ALL)
2763 STEXI
2764 @item -s
2765 @findex -s
2766 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
2767 (@pxref{gdb_usage}).
2768 ETEXI
2770 DEF("d", HAS_ARG, QEMU_OPTION_d, \
2771 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n",
2772 QEMU_ARCH_ALL)
2773 STEXI
2774 @item -d @var{item1}[,...]
2775 @findex -d
2776 Enable logging of specified items. Use '-d help' for a list of log items.
2777 ETEXI
2779 DEF("D", HAS_ARG, QEMU_OPTION_D, \
2780 "-D logfile output log to logfile (default stderr)\n",
2781 QEMU_ARCH_ALL)
2782 STEXI
2783 @item -D @var{logfile}
2784 @findex -D
2785 Output log in @var{logfile} instead of to stderr
2786 ETEXI
2788 DEF("L", HAS_ARG, QEMU_OPTION_L, \
2789 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
2790 QEMU_ARCH_ALL)
2791 STEXI
2792 @item -L @var{path}
2793 @findex -L
2794 Set the directory for the BIOS, VGA BIOS and keymaps.
2795 ETEXI
2797 DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
2798 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL)
2799 STEXI
2800 @item -bios @var{file}
2801 @findex -bios
2802 Set the filename for the BIOS.
2803 ETEXI
2805 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
2806 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL)
2807 STEXI
2808 @item -enable-kvm
2809 @findex -enable-kvm
2810 Enable KVM full virtualization support. This option is only available
2811 if KVM support is enabled when compiling.
2812 ETEXI
2814 DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
2815 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL)
2816 DEF("xen-create", 0, QEMU_OPTION_xen_create,
2817 "-xen-create create domain using xen hypercalls, bypassing xend\n"
2818 " warning: should not be used when xend is in use\n",
2819 QEMU_ARCH_ALL)
2820 DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
2821 "-xen-attach attach to existing xen domain\n"
2822 " xend will use this when starting QEMU\n",
2823 QEMU_ARCH_ALL)
2824 STEXI
2825 @item -xen-domid @var{id}
2826 @findex -xen-domid
2827 Specify xen guest domain @var{id} (XEN only).
2828 @item -xen-create
2829 @findex -xen-create
2830 Create domain using xen hypercalls, bypassing xend.
2831 Warning: should not be used when xend is in use (XEN only).
2832 @item -xen-attach
2833 @findex -xen-attach
2834 Attach to existing xen domain.
2835 xend will use this when starting QEMU (XEN only).
2836 ETEXI
2838 DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
2839 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL)
2840 STEXI
2841 @item -no-reboot
2842 @findex -no-reboot
2843 Exit instead of rebooting.
2844 ETEXI
2846 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
2847 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL)
2848 STEXI
2849 @item -no-shutdown
2850 @findex -no-shutdown
2851 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
2852 This allows for instance switching to monitor to commit changes to the
2853 disk image.
2854 ETEXI
2856 DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
2857 "-loadvm [tag|id]\n" \
2858 " start right away with a saved state (loadvm in monitor)\n",
2859 QEMU_ARCH_ALL)
2860 STEXI
2861 @item -loadvm @var{file}
2862 @findex -loadvm
2863 Start right away with a saved state (@code{loadvm} in monitor)
2864 ETEXI
2866 #ifndef _WIN32
2867 DEF("daemonize", 0, QEMU_OPTION_daemonize, \
2868 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
2869 #endif
2870 STEXI
2871 @item -daemonize
2872 @findex -daemonize
2873 Daemonize the QEMU process after initialization. QEMU will not detach from
2874 standard IO until it is ready to receive connections on any of its devices.
2875 This option is a useful way for external programs to launch QEMU without having
2876 to cope with initialization race conditions.
2877 ETEXI
2879 DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
2880 "-option-rom rom load a file, rom, into the option ROM space\n",
2881 QEMU_ARCH_ALL)
2882 STEXI
2883 @item -option-rom @var{file}
2884 @findex -option-rom
2885 Load the contents of @var{file} as an option ROM.
2886 This option is useful to load things like EtherBoot.
2887 ETEXI
2889 DEF("clock", HAS_ARG, QEMU_OPTION_clock, \
2890 "-clock force the use of the given methods for timer alarm.\n" \
2891 " To see what timers are available use '-clock help'\n",
2892 QEMU_ARCH_ALL)
2893 STEXI
2894 @item -clock @var{method}
2895 @findex -clock
2896 Force the use of the given methods for timer alarm. To see what timers
2897 are available use @code{-clock help}.
2898 ETEXI
2900 HXCOMM Options deprecated by -rtc
2901 DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
2902 DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
2904 DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
2905 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
2906 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
2907 QEMU_ARCH_ALL)
2909 STEXI
2911 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
2912 @findex -rtc
2913 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
2914 UTC or local time, respectively. @code{localtime} is required for correct date in
2915 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
2916 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
2918 By default the RTC is driven by the host system time. This allows using of the
2919 RTC as accurate reference clock inside the guest, specifically if the host
2920 time is smoothly following an accurate external reference clock, e.g. via NTP.
2921 If you want to isolate the guest time from the host, you can set @option{clock}
2922 to @code{rt} instead. To even prevent it from progressing during suspension,
2923 you can set it to @code{vm}.
2925 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
2926 specifically with Windows' ACPI HAL. This option will try to figure out how
2927 many timer interrupts were not processed by the Windows guest and will
2928 re-inject them.
2929 ETEXI
2931 DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
2932 "-icount [N|auto]\n" \
2933 " enable virtual instruction counter with 2^N clock ticks per\n" \
2934 " instruction\n", QEMU_ARCH_ALL)
2935 STEXI
2936 @item -icount [@var{N}|auto]
2937 @findex -icount
2938 Enable virtual instruction counter. The virtual cpu will execute one
2939 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
2940 then the virtual cpu speed will be automatically adjusted to keep virtual
2941 time within a few seconds of real time.
2943 Note that while this option can give deterministic behavior, it does not
2944 provide cycle accurate emulation. Modern CPUs contain superscalar out of
2945 order cores with complex cache hierarchies. The number of instructions
2946 executed often has little or no correlation with actual performance.
2947 ETEXI
2949 DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
2950 "-watchdog i6300esb|ib700\n" \
2951 " enable virtual hardware watchdog [default=none]\n",
2952 QEMU_ARCH_ALL)
2953 STEXI
2954 @item -watchdog @var{model}
2955 @findex -watchdog
2956 Create a virtual hardware watchdog device. Once enabled (by a guest
2957 action), the watchdog must be periodically polled by an agent inside
2958 the guest or else the guest will be restarted.
2960 The @var{model} is the model of hardware watchdog to emulate. Choices
2961 for model are: @code{ib700} (iBASE 700) which is a very simple ISA
2962 watchdog with a single timer, or @code{i6300esb} (Intel 6300ESB I/O
2963 controller hub) which is a much more featureful PCI-based dual-timer
2964 watchdog. Choose a model for which your guest has drivers.
2966 Use @code{-watchdog help} to list available hardware models. Only one
2967 watchdog can be enabled for a guest.
2968 ETEXI
2970 DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
2971 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
2972 " action when watchdog fires [default=reset]\n",
2973 QEMU_ARCH_ALL)
2974 STEXI
2975 @item -watchdog-action @var{action}
2976 @findex -watchdog-action
2978 The @var{action} controls what QEMU will do when the watchdog timer
2979 expires.
2980 The default is
2981 @code{reset} (forcefully reset the guest).
2982 Other possible actions are:
2983 @code{shutdown} (attempt to gracefully shutdown the guest),
2984 @code{poweroff} (forcefully poweroff the guest),
2985 @code{pause} (pause the guest),
2986 @code{debug} (print a debug message and continue), or
2987 @code{none} (do nothing).
2989 Note that the @code{shutdown} action requires that the guest responds
2990 to ACPI signals, which it may not be able to do in the sort of
2991 situations where the watchdog would have expired, and thus
2992 @code{-watchdog-action shutdown} is not recommended for production use.
2994 Examples:
2996 @table @code
2997 @item -watchdog i6300esb -watchdog-action pause
2998 @item -watchdog ib700
2999 @end table
3000 ETEXI
3002 DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
3003 "-echr chr set terminal escape character instead of ctrl-a\n",
3004 QEMU_ARCH_ALL)
3005 STEXI
3007 @item -echr @var{numeric_ascii_value}
3008 @findex -echr
3009 Change the escape character used for switching to the monitor when using
3010 monitor and serial sharing. The default is @code{0x01} when using the
3011 @code{-nographic} option. @code{0x01} is equal to pressing
3012 @code{Control-a}. You can select a different character from the ascii
3013 control keys where 1 through 26 map to Control-a through Control-z. For
3014 instance you could use the either of the following to change the escape
3015 character to Control-t.
3016 @table @code
3017 @item -echr 0x14
3018 @item -echr 20
3019 @end table
3020 ETEXI
3022 DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
3023 "-virtioconsole c\n" \
3024 " set virtio console\n", QEMU_ARCH_ALL)
3025 STEXI
3026 @item -virtioconsole @var{c}
3027 @findex -virtioconsole
3028 Set virtio console.
3030 This option is maintained for backward compatibility.
3032 Please use @code{-device virtconsole} for the new way of invocation.
3033 ETEXI
3035 DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
3036 "-show-cursor show cursor\n", QEMU_ARCH_ALL)
3037 STEXI
3038 @item -show-cursor
3039 @findex -show-cursor
3040 Show cursor.
3041 ETEXI
3043 DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
3044 "-tb-size n set TB size\n", QEMU_ARCH_ALL)
3045 STEXI
3046 @item -tb-size @var{n}
3047 @findex -tb-size
3048 Set TB size.
3049 ETEXI
3051 DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
3052 "-incoming p prepare for incoming migration, listen on port p\n",
3053 QEMU_ARCH_ALL)
3054 STEXI
3055 @item -incoming @var{port}
3056 @findex -incoming
3057 Prepare for incoming migration, listen on @var{port}.
3058 ETEXI
3060 DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
3061 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL)
3062 STEXI
3063 @item -nodefaults
3064 @findex -nodefaults
3065 Don't create default devices. Normally, QEMU sets the default devices like serial
3066 port, parallel port, virtual console, monitor device, VGA adapter, floppy and
3067 CD-ROM drive and others. The @code{-nodefaults} option will disable all those
3068 default devices.
3069 ETEXI
3071 #ifndef _WIN32
3072 DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
3073 "-chroot dir chroot to dir just before starting the VM\n",
3074 QEMU_ARCH_ALL)
3075 #endif
3076 STEXI
3077 @item -chroot @var{dir}
3078 @findex -chroot
3079 Immediately before starting guest execution, chroot to the specified
3080 directory. Especially useful in combination with -runas.
3081 ETEXI
3083 #ifndef _WIN32
3084 DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
3085 "-runas user change to user id user just before starting the VM\n",
3086 QEMU_ARCH_ALL)
3087 #endif
3088 STEXI
3089 @item -runas @var{user}
3090 @findex -runas
3091 Immediately before starting guest execution, drop root privileges, switching
3092 to the specified user.
3093 ETEXI
3095 DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
3096 "-prom-env variable=value\n"
3097 " set OpenBIOS nvram variables\n",
3098 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3099 STEXI
3100 @item -prom-env @var{variable}=@var{value}
3101 @findex -prom-env
3102 Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
3103 ETEXI
3104 DEF("semihosting", 0, QEMU_OPTION_semihosting,
3105 "-semihosting semihosting mode\n",
3106 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32)
3107 STEXI
3108 @item -semihosting
3109 @findex -semihosting
3110 Semihosting mode (ARM, M68K, Xtensa only).
3111 ETEXI
3112 DEF("old-param", 0, QEMU_OPTION_old_param,
3113 "-old-param old param mode\n", QEMU_ARCH_ARM)
3114 STEXI
3115 @item -old-param
3116 @findex -old-param (ARM)
3117 Old param mode (ARM only).
3118 ETEXI
3120 DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
3121 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n",
3122 QEMU_ARCH_ALL)
3123 STEXI
3124 @item -sandbox @var{arg}
3125 @findex -sandbox
3126 Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
3127 disable it. The default is 'off'.
3128 ETEXI
3130 DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
3131 "-readconfig <file>\n", QEMU_ARCH_ALL)
3132 STEXI
3133 @item -readconfig @var{file}
3134 @findex -readconfig
3135 Read device configuration from @var{file}. This approach is useful when you want to spawn
3136 QEMU process with many command line options but you don't want to exceed the command line
3137 character limit.
3138 ETEXI
3139 DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
3140 "-writeconfig <file>\n"
3141 " read/write config file\n", QEMU_ARCH_ALL)
3142 STEXI
3143 @item -writeconfig @var{file}
3144 @findex -writeconfig
3145 Write device configuration to @var{file}. The @var{file} can be either filename to save
3146 command line and device configuration into file or dash @code{-}) character to print the
3147 output to stdout. This can be later used as input file for @code{-readconfig} option.
3148 ETEXI
3149 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig,
3150 "-nodefconfig\n"
3151 " do not load default config files at startup\n",
3152 QEMU_ARCH_ALL)
3153 STEXI
3154 @item -nodefconfig
3155 @findex -nodefconfig
3156 Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
3157 The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
3158 ETEXI
3159 DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
3160 "-no-user-config\n"
3161 " do not load user-provided config files at startup\n",
3162 QEMU_ARCH_ALL)
3163 STEXI
3164 @item -no-user-config
3165 @findex -no-user-config
3166 The @code{-no-user-config} option makes QEMU not load any of the user-provided
3167 config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config
3168 files from @var{datadir}.
3169 ETEXI
3170 DEF("trace", HAS_ARG, QEMU_OPTION_trace,
3171 "-trace [events=<file>][,file=<file>]\n"
3172 " specify tracing options\n",
3173 QEMU_ARCH_ALL)
3174 STEXI
3175 HXCOMM This line is not accurate, as some sub-options are backend-specific but
3176 HXCOMM HX does not support conditional compilation of text.
3177 @item -trace [events=@var{file}][,file=@var{file}]
3178 @findex -trace
3180 Specify tracing options.
3182 @table @option
3183 @item events=@var{file}
3184 Immediately enable events listed in @var{file}.
3185 The file must contain one event name (as listed in the @var{trace-events} file)
3186 per line.
3187 This option is only available if QEMU has been compiled with
3188 either @var{simple} or @var{stderr} tracing backend.
3189 @item file=@var{file}
3190 Log output traces to @var{file}.
3192 This option is only available if QEMU has been compiled with
3193 the @var{simple} tracing backend.
3194 @end table
3195 ETEXI
3197 HXCOMM Internal use
3198 DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL)
3199 DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL)
3201 #ifdef __linux__
3202 DEF("enable-fips", 0, QEMU_OPTION_enablefips,
3203 "-enable-fips enable FIPS 140-2 compliance\n",
3204 QEMU_ARCH_ALL)
3205 #endif
3206 STEXI
3207 @item -enable-fips
3208 @findex -enable-fips
3209 Enable FIPS 140-2 compliance mode.
3210 ETEXI
3212 HXCOMM Deprecated by -machine accel=tcg property
3213 DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386)
3215 HXCOMM Deprecated by kvm-pit driver properties
3216 DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection,
3217 "", QEMU_ARCH_I386)
3219 HXCOMM Deprecated (ignored)
3220 DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386)
3222 HXCOMM Deprecated by -machine kernel_irqchip=on|off property
3223 DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386)
3225 HXCOMM Deprecated (ignored)
3226 DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL)
3228 DEF("object", HAS_ARG, QEMU_OPTION_object,
3229 "-object TYPENAME[,PROP1=VALUE1,...]\n"
3230 " create an new object of type TYPENAME setting properties\n"
3231 " in the order they are specified. Note that the 'id'\n"
3232 " property must be set. These objects are placed in the\n"
3233 " '/objects' path.\n",
3234 QEMU_ARCH_ALL)
3235 STEXI
3236 @item -object @var{typename}[,@var{prop1}=@var{value1},...]
3237 @findex -object
3238 Create an new object of type @var{typename} setting properties
3239 in the order they are specified. Note that the 'id'
3240 property must be set. These objects are placed in the
3241 '/objects' path.
3242 ETEXI
3244 DEF("msg", HAS_ARG, QEMU_OPTION_msg,
3245 "-msg timestamp[=on|off]\n"
3246 " change the format of messages\n"
3247 " on|off controls leading timestamps (default:on)\n",
3248 QEMU_ARCH_ALL)
3249 STEXI
3250 @item -msg timestamp[=on|off]
3251 @findex -msg
3252 prepend a timestamp to each log message.(default:on)
3253 ETEXI
3255 HXCOMM This is the last statement. Insert new options before this line!
3256 STEXI
3257 @end table
3258 ETEXI