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1HXCOMM Use DEFHEADING() to define headings in both help text and texi
2HXCOMM Text between STEXI and ETEXI are copied to texi version and
3HXCOMM discarded from C version
4HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to
5HXCOMM construct option structures, enums and help message for specified
6HXCOMM architectures.
7HXCOMM HXCOMM can be used for comments, discarded from both texi and C
8
9DEFHEADING(Standard options:)
10STEXI
11@table @option
12ETEXI
13
14DEF("help", 0, QEMU_OPTION_h,
15 "-h or -help display this help and exit\n", QEMU_ARCH_ALL)
16STEXI
17@item -h
18@findex -h
19Display help and exit
20ETEXI
21
22DEF("version", 0, QEMU_OPTION_version,
23 "-version display version information and exit\n", QEMU_ARCH_ALL)
24STEXI
25@item -version
26@findex -version
27Display version information and exit
28ETEXI
29
30DEF("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)
40STEXI
41@item -machine [type=]@var{name}[,prop=@var{value}[,...]]
42@findex -machine
43Select the emulated machine by @var{name}. Use @code{-machine help} to list
44available machines. Supported machine properties are:
45@table @option
46@item accel=@var{accels1}[:@var{accels2}[:...]]
47This is used to enable an accelerator. Depending on the target architecture,
48kvm, xen, or tcg can be available. By default, tcg is used. If there is more
49than one accelerator specified, the next one is used if the previous one fails
50to initialize.
51@item kernel_irqchip=on|off
52Enables in-kernel irqchip support for the chosen accelerator when available.
53@item kvm_shadow_mem=size
54Defines the size of the KVM shadow MMU.
55@item dump-guest-core=on|off
56Include guest memory in a core dump. The default is on.
57@item mem-merge=on|off
58Enables or disables memory merge support. This feature, when supported by
59the host, de-duplicates identical memory pages among VMs instances
60(enabled by default).
61@end table
62ETEXI
63
64HXCOMM Deprecated by -machine
65DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL)
66
67DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
68 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL)
69STEXI
70@item -cpu @var{model}
71@findex -cpu
72Select CPU model (@code{-cpu help} for list and additional feature selection)
73ETEXI
74
75DEF("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)
84STEXI
85@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
86@findex -smp
87Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
88CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
89to 4.
90For the PC target, the number of @var{cores} per socket, the number
91of @var{threads} per cores and the total number of @var{sockets} can be
92specified. Missing values will be computed. If any on the three values is
93given, the total number of CPUs @var{n} can be omitted. @var{maxcpus}
94specifies the maximum number of hotpluggable CPUs.
95ETEXI
96
97DEF("numa", HAS_ARG, QEMU_OPTION_numa,
98 "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL)
99STEXI
100@item -numa node[,mem=@var{size}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}]
101@findex -numa
102Simulate a multi node NUMA system. If @samp{mem}
103and @samp{cpus} are omitted, resources are split equally. Also, note
104that the -@option{numa} option doesn't allocate any of the specified
105resources. That is, it just assigns existing resources to NUMA nodes. This
106means that one still has to use the @option{-m}, @option{-smp} options
107to allocate RAM and VCPUs respectively.
108ETEXI
109
110DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
111 "-add-fd fd=fd,set=set[,opaque=opaque]\n"
112 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL)
113STEXI
114@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}]
115@findex -add-fd
116
117Add a file descriptor to an fd set. Valid options are:
118
119@table @option
120@item fd=@var{fd}
121This option defines the file descriptor of which a duplicate is added to fd set.
122The file descriptor cannot be stdin, stdout, or stderr.
123@item set=@var{set}
124This option defines the ID of the fd set to add the file descriptor to.
125@item opaque=@var{opaque}
126This option defines a free-form string that can be used to describe @var{fd}.
127@end table
128
129You can open an image using pre-opened file descriptors from an fd set:
130@example
131qemu-system-i386
132-add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
133-add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
134-drive file=/dev/fdset/2,index=0,media=disk
135@end example
136ETEXI
137
138DEF("set", HAS_ARG, QEMU_OPTION_set,
139 "-set group.id.arg=value\n"
140 " set <arg> parameter for item <id> of type <group>\n"
141 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL)
142STEXI
143@item -set @var{group}.@var{id}.@var{arg}=@var{value}
144@findex -set
145Set parameter @var{arg} for item @var{id} of type @var{group}\n"
146ETEXI
147
148DEF("global", HAS_ARG, QEMU_OPTION_global,
149 "-global driver.prop=value\n"
150 " set a global default for a driver property\n",
151 QEMU_ARCH_ALL)
152STEXI
153@item -global @var{driver}.@var{prop}=@var{value}
154@findex -global
155Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.:
156
157@example
158qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk
159@end example
160
161In particular, you can use this to set driver properties for devices which are
162created automatically by the machine model. To create a device which is not
163created automatically and set properties on it, use -@option{device}.
164ETEXI
165
166DEF("boot", HAS_ARG, QEMU_OPTION_boot,
167 "-boot [order=drives][,once=drives][,menu=on|off]\n"
168 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
169 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
170 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n"
171 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n"
172 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n",
173 QEMU_ARCH_ALL)
174STEXI
175@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]
176@findex -boot
177Specify boot order @var{drives} as a string of drive letters. Valid
178drive letters depend on the target achitecture. The x86 PC uses: a, b
179(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
180from network adapter 1-4), hard disk boot is the default. To apply a
181particular boot order only on the first startup, specify it via
182@option{once}.
183
184Interactive boot menus/prompts can be enabled via @option{menu=on} as far
185as firmware/BIOS supports them. The default is non-interactive boot.
186
187A splash picture could be passed to bios, enabling user to show it as logo,
188when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
189supports them. Currently Seabios for X86 system support it.
190limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
191format(true color). The resolution should be supported by the SVGA mode, so
192the recommended is 320x240, 640x480, 800x640.
193
194A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms
195when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not
196reboot, qemu passes '-1' to bios by default. Currently Seabios for X86
197system support it.
198
199Do strict boot via @option{strict=on} as far as firmware/BIOS
200supports it. This only effects when boot priority is changed by
201bootindex options. The default is non-strict boot.
202
203@example
204# try to boot from network first, then from hard disk
205qemu-system-i386 -boot order=nc
206# boot from CD-ROM first, switch back to default order after reboot
207qemu-system-i386 -boot once=d
208# boot with a splash picture for 5 seconds.
209qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
210@end example
211
212Note: The legacy format '-boot @var{drives}' is still supported but its
213use is discouraged as it may be removed from future versions.
214ETEXI
215
216DEF("m", HAS_ARG, QEMU_OPTION_m,
217 "-m[emory] [size=]megs[,slots=n,maxmem=size]\n"
218 " configure guest RAM\n"
219 " size: initial amount of guest memory (default: "
220 stringify(DEFAULT_RAM_SIZE) "MiB)\n"
221 " slots: number of hotplug slots (default: none)\n"
222 " maxmem: maximum amount of guest memory (default: none)\n",
223 QEMU_ARCH_ALL)
224STEXI
225@item -m [size=]@var{megs}
226@findex -m
227Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally,
228a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or
229gigabytes respectively. Optional pair @var{slots}, @var{maxmem} could be used
230to set amount of hotluggable memory slots and possible maximum amount of memory.
231ETEXI
232
233DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
234 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
235STEXI
236@item -mem-path @var{path}
237@findex -mem-path
238Allocate guest RAM from a temporarily created file in @var{path}.
239ETEXI
240
241DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
242 "-mem-prealloc preallocate guest memory (use with -mem-path)\n",
243 QEMU_ARCH_ALL)
244STEXI
245@item -mem-prealloc
246@findex -mem-prealloc
247Preallocate memory when using -mem-path.
248ETEXI
249
250DEF("k", HAS_ARG, QEMU_OPTION_k,
251 "-k language use keyboard layout (for example 'fr' for French)\n",
252 QEMU_ARCH_ALL)
253STEXI
254@item -k @var{language}
255@findex -k
256Use keyboard layout @var{language} (for example @code{fr} for
257French). This option is only needed where it is not easy to get raw PC
258keycodes (e.g. on Macs, with some X11 servers or with a VNC
259display). You don't normally need to use it on PC/Linux or PC/Windows
260hosts.
261
262The available layouts are:
263@example
264ar de-ch es fo fr-ca hu ja mk no pt-br sv
265da en-gb et fr fr-ch is lt nl pl ru th
266de en-us fi fr-be hr it lv nl-be pt sl tr
267@end example
268
269The default is @code{en-us}.
270ETEXI
271
272
273DEF("audio-help", 0, QEMU_OPTION_audio_help,
274 "-audio-help print list of audio drivers and their options\n",
275 QEMU_ARCH_ALL)
276STEXI
277@item -audio-help
278@findex -audio-help
279Will show the audio subsystem help: list of drivers, tunable
280parameters.
281ETEXI
282
283DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
284 "-soundhw c1,... enable audio support\n"
285 " and only specified sound cards (comma separated list)\n"
286 " use '-soundhw help' to get the list of supported cards\n"
287 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL)
288STEXI
289@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
290@findex -soundhw
291Enable audio and selected sound hardware. Use 'help' to print all
292available sound hardware.
293
294@example
295qemu-system-i386 -soundhw sb16,adlib disk.img
296qemu-system-i386 -soundhw es1370 disk.img
297qemu-system-i386 -soundhw ac97 disk.img
298qemu-system-i386 -soundhw hda disk.img
299qemu-system-i386 -soundhw all disk.img
300qemu-system-i386 -soundhw help
301@end example
302
303Note that Linux's i810_audio OSS kernel (for AC97) module might
304require manually specifying clocking.
305
306@example
307modprobe i810_audio clocking=48000
308@end example
309ETEXI
310
311DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
312 "-balloon none disable balloon device\n"
313 "-balloon virtio[,addr=str]\n"
314 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL)
315STEXI
316@item -balloon none
317@findex -balloon
318Disable balloon device.
319@item -balloon virtio[,addr=@var{addr}]
320Enable virtio balloon device (default), optionally with PCI address
321@var{addr}.
322ETEXI
323
324DEF("device", HAS_ARG, QEMU_OPTION_device,
325 "-device driver[,prop[=value][,...]]\n"
326 " add device (based on driver)\n"
327 " prop=value,... sets driver properties\n"
328 " use '-device help' to print all possible drivers\n"
329 " use '-device driver,help' to print all possible properties\n",
330 QEMU_ARCH_ALL)
331STEXI
332@item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
333@findex -device
334Add device @var{driver}. @var{prop}=@var{value} sets driver
335properties. Valid properties depend on the driver. To get help on
336possible drivers and properties, use @code{-device help} and
337@code{-device @var{driver},help}.
338ETEXI
339
340DEF("name", HAS_ARG, QEMU_OPTION_name,
341 "-name string1[,process=string2][,debug-threads=on|off]\n"
342 " set the name of the guest\n"
343 " string1 sets the window title and string2 the process name (on Linux)\n"
344 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n"
345 " NOTE: The thread names are for debugging and not a stable API.\n",
346 QEMU_ARCH_ALL)
347STEXI
348@item -name @var{name}
349@findex -name
350Sets the @var{name} of the guest.
351This name will be displayed in the SDL window caption.
352The @var{name} will also be used for the VNC server.
353Also optionally set the top visible process name in Linux.
354Naming of individual threads can also be enabled on Linux to aid debugging.
355ETEXI
356
357DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
358 "-uuid %08x-%04x-%04x-%04x-%012x\n"
359 " specify machine UUID\n", QEMU_ARCH_ALL)
360STEXI
361@item -uuid @var{uuid}
362@findex -uuid
363Set system UUID.
364ETEXI
365
366STEXI
367@end table
368ETEXI
369DEFHEADING()
370
371DEFHEADING(Block device options:)
372STEXI
373@table @option
374ETEXI
375
376DEF("fda", HAS_ARG, QEMU_OPTION_fda,
377 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
378DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
379STEXI
380@item -fda @var{file}
381@item -fdb @var{file}
382@findex -fda
383@findex -fdb
384Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can
385use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}).
386ETEXI
387
388DEF("hda", HAS_ARG, QEMU_OPTION_hda,
389 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
390DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
391DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
392 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
393DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
394STEXI
395@item -hda @var{file}
396@item -hdb @var{file}
397@item -hdc @var{file}
398@item -hdd @var{file}
399@findex -hda
400@findex -hdb
401@findex -hdc
402@findex -hdd
403Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
404ETEXI
405
406DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
407 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
408 QEMU_ARCH_ALL)
409STEXI
410@item -cdrom @var{file}
411@findex -cdrom
412Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
413@option{-cdrom} at the same time). You can use the host CD-ROM by
414using @file{/dev/cdrom} as filename (@pxref{host_drives}).
415ETEXI
416
417DEF("drive", HAS_ARG, QEMU_OPTION_drive,
418 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
419 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
420 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
421 " [,serial=s][,addr=A][,rerror=ignore|stop|report]\n"
422 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n"
423 " [,readonly=on|off][,copy-on-read=on|off]\n"
424 " [,detect-zeroes=on|off|unmap]\n"
425 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n"
426 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n"
427 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n"
428 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n"
429 " [[,iops_size=is]]\n"
430 " use 'file' as a drive image\n", QEMU_ARCH_ALL)
431STEXI
432@item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
433@findex -drive
434
435Define a new drive. Valid options are:
436
437@table @option
438@item file=@var{file}
439This option defines which disk image (@pxref{disk_images}) to use with
440this drive. If the filename contains comma, you must double it
441(for instance, "file=my,,file" to use file "my,file").
442
443Special files such as iSCSI devices can be specified using protocol
444specific URLs. See the section for "Device URL Syntax" for more information.
445@item if=@var{interface}
446This option defines on which type on interface the drive is connected.
447Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio.
448@item bus=@var{bus},unit=@var{unit}
449These options define where is connected the drive by defining the bus number and
450the unit id.
451@item index=@var{index}
452This option defines where is connected the drive by using an index in the list
453of available connectors of a given interface type.
454@item media=@var{media}
455This option defines the type of the media: disk or cdrom.
456@item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
457These options have the same definition as they have in @option{-hdachs}.
458@item snapshot=@var{snapshot}
459@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive
460(see @option{-snapshot}).
461@item cache=@var{cache}
462@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data.
463@item aio=@var{aio}
464@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
465@item discard=@var{discard}
466@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.
467@item format=@var{format}
468Specify which disk @var{format} will be used rather than detecting
469the format. Can be used to specifiy format=raw to avoid interpreting
470an untrusted format header.
471@item serial=@var{serial}
472This option specifies the serial number to assign to the device.
473@item addr=@var{addr}
474Specify the controller's PCI address (if=virtio only).
475@item werror=@var{action},rerror=@var{action}
476Specify which @var{action} to take on write and read errors. Valid actions are:
477"ignore" (ignore the error and try to continue), "stop" (pause QEMU),
478"report" (report the error to the guest), "enospc" (pause QEMU only if the
479host disk is full; report the error to the guest otherwise).
480The default setting is @option{werror=enospc} and @option{rerror=report}.
481@item readonly
482Open drive @option{file} as read-only. Guest write attempts will fail.
483@item copy-on-read=@var{copy-on-read}
484@var{copy-on-read} is "on" or "off" and enables whether to copy read backing
485file sectors into the image file.
486@item detect-zeroes=@var{detect-zeroes}
487@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic
488conversion of plain zero writes by the OS to driver specific optimized
489zero write commands. You may even choose "unmap" if @var{discard} is set
490to "unmap" to allow a zero write to be converted to an UNMAP operation.
491@end table
492
493By default, the @option{cache=writeback} mode is used. It will report data
494writes as completed as soon as the data is present in the host page cache.
495This is safe as long as your guest OS makes sure to correctly flush disk caches
496where needed. If your guest OS does not handle volatile disk write caches
497correctly and your host crashes or loses power, then the guest may experience
498data corruption.
499
500For such guests, you should consider using @option{cache=writethrough}. This
501means that the host page cache will be used to read and write data, but write
502notification will be sent to the guest only after QEMU has made sure to flush
503each write to the disk. Be aware that this has a major impact on performance.
504
505The host page cache can be avoided entirely with @option{cache=none}. This will
506attempt to do disk IO directly to the guest's memory. QEMU may still perform
507an internal copy of the data. Note that this is considered a writeback mode and
508the guest OS must handle the disk write cache correctly in order to avoid data
509corruption on host crashes.
510
511The host page cache can be avoided while only sending write notifications to
512the guest when the data has been flushed to the disk using
513@option{cache=directsync}.
514
515In case you don't care about data integrity over host failures, use
516@option{cache=unsafe}. This option tells QEMU that it never needs to write any
517data to the disk but can instead keep things in cache. If anything goes wrong,
518like your host losing power, the disk storage getting disconnected accidentally,
519etc. your image will most probably be rendered unusable. When using
520the @option{-snapshot} option, unsafe caching is always used.
521
522Copy-on-read avoids accessing the same backing file sectors repeatedly and is
523useful when the backing file is over a slow network. By default copy-on-read
524is off.
525
526Instead of @option{-cdrom} you can use:
527@example
528qemu-system-i386 -drive file=file,index=2,media=cdrom
529@end example
530
531Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
532use:
533@example
534qemu-system-i386 -drive file=file,index=0,media=disk
535qemu-system-i386 -drive file=file,index=1,media=disk
536qemu-system-i386 -drive file=file,index=2,media=disk
537qemu-system-i386 -drive file=file,index=3,media=disk
538@end example
539
540You can open an image using pre-opened file descriptors from an fd set:
541@example
542qemu-system-i386
543-add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
544-add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
545-drive file=/dev/fdset/2,index=0,media=disk
546@end example
547
548You can connect a CDROM to the slave of ide0:
549@example
550qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
551@end example
552
553If you don't specify the "file=" argument, you define an empty drive:
554@example
555qemu-system-i386 -drive if=ide,index=1,media=cdrom
556@end example
557
558You can connect a SCSI disk with unit ID 6 on the bus #0:
559@example
560qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6
561@end example
562
563Instead of @option{-fda}, @option{-fdb}, you can use:
564@example
565qemu-system-i386 -drive file=file,index=0,if=floppy
566qemu-system-i386 -drive file=file,index=1,if=floppy
567@end example
568
569By default, @var{interface} is "ide" and @var{index} is automatically
570incremented:
571@example
572qemu-system-i386 -drive file=a -drive file=b"
573@end example
574is interpreted like:
575@example
576qemu-system-i386 -hda a -hdb b
577@end example
578ETEXI
579
580DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
581 "-mtdblock file use 'file' as on-board Flash memory image\n",
582 QEMU_ARCH_ALL)
583STEXI
584@item -mtdblock @var{file}
585@findex -mtdblock
586Use @var{file} as on-board Flash memory image.
587ETEXI
588
589DEF("sd", HAS_ARG, QEMU_OPTION_sd,
590 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL)
591STEXI
592@item -sd @var{file}
593@findex -sd
594Use @var{file} as SecureDigital card image.
595ETEXI
596
597DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
598 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL)
599STEXI
600@item -pflash @var{file}
601@findex -pflash
602Use @var{file} as a parallel flash image.
603ETEXI
604
605DEF("snapshot", 0, QEMU_OPTION_snapshot,
606 "-snapshot write to temporary files instead of disk image files\n",
607 QEMU_ARCH_ALL)
608STEXI
609@item -snapshot
610@findex -snapshot
611Write to temporary files instead of disk image files. In this case,
612the raw disk image you use is not written back. You can however force
613the write back by pressing @key{C-a s} (@pxref{disk_images}).
614ETEXI
615
616DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
617 "-hdachs c,h,s[,t]\n" \
618 " force hard disk 0 physical geometry and the optional BIOS\n" \
619 " translation (t=none or lba) (usually QEMU can guess them)\n",
620 QEMU_ARCH_ALL)
621STEXI
622@item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
623@findex -hdachs
624Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
625@var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
626translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
627all those parameters. This option is useful for old MS-DOS disk
628images.
629ETEXI
630
631DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
632 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
633 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
634 QEMU_ARCH_ALL)
635
636STEXI
637
638@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}]
639@findex -fsdev
640Define a new file system device. Valid options are:
641@table @option
642@item @var{fsdriver}
643This option specifies the fs driver backend to use.
644Currently "local", "handle" and "proxy" file system drivers are supported.
645@item id=@var{id}
646Specifies identifier for this device
647@item path=@var{path}
648Specifies the export path for the file system device. Files under
649this path will be available to the 9p client on the guest.
650@item security_model=@var{security_model}
651Specifies the security model to be used for this export path.
652Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
653In "passthrough" security model, files are stored using the same
654credentials as they are created on the guest. This requires QEMU
655to run as root. In "mapped-xattr" security model, some of the file
656attributes like uid, gid, mode bits and link target are stored as
657file attributes. For "mapped-file" these attributes are stored in the
658hidden .virtfs_metadata directory. Directories exported by this security model cannot
659interact with other unix tools. "none" security model is same as
660passthrough except the sever won't report failures if it fails to
661set file attributes like ownership. Security model is mandatory
662only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
663security model as a parameter.
664@item writeout=@var{writeout}
665This is an optional argument. The only supported value is "immediate".
666This means that host page cache will be used to read and write data but
667write notification will be sent to the guest only when the data has been
668reported as written by the storage subsystem.
669@item readonly
670Enables exporting 9p share as a readonly mount for guests. By default
671read-write access is given.
672@item socket=@var{socket}
673Enables proxy filesystem driver to use passed socket file for communicating
674with virtfs-proxy-helper
675@item sock_fd=@var{sock_fd}
676Enables proxy filesystem driver to use passed socket descriptor for
677communicating with virtfs-proxy-helper. Usually a helper like libvirt
678will create socketpair and pass one of the fds as sock_fd
679@end table
680
681-fsdev option is used along with -device driver "virtio-9p-pci".
682@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
683Options for virtio-9p-pci driver are:
684@table @option
685@item fsdev=@var{id}
686Specifies the id value specified along with -fsdev option
687@item mount_tag=@var{mount_tag}
688Specifies the tag name to be used by the guest to mount this export point
689@end table
690
691ETEXI
692
693DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
694 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
695 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
696 QEMU_ARCH_ALL)
697
698STEXI
699
700@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}]
701@findex -virtfs
702
703The general form of a Virtual File system pass-through options are:
704@table @option
705@item @var{fsdriver}
706This option specifies the fs driver backend to use.
707Currently "local", "handle" and "proxy" file system drivers are supported.
708@item id=@var{id}
709Specifies identifier for this device
710@item path=@var{path}
711Specifies the export path for the file system device. Files under
712this path will be available to the 9p client on the guest.
713@item security_model=@var{security_model}
714Specifies the security model to be used for this export path.
715Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
716In "passthrough" security model, files are stored using the same
717credentials as they are created on the guest. This requires QEMU
718to run as root. In "mapped-xattr" security model, some of the file
719attributes like uid, gid, mode bits and link target are stored as
720file attributes. For "mapped-file" these attributes are stored in the
721hidden .virtfs_metadata directory. Directories exported by this security model cannot
722interact with other unix tools. "none" security model is same as
723passthrough except the sever won't report failures if it fails to
724set file attributes like ownership. Security model is mandatory only
725for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
726model as a parameter.
727@item writeout=@var{writeout}
728This is an optional argument. The only supported value is "immediate".
729This means that host page cache will be used to read and write data but
730write notification will be sent to the guest only when the data has been
731reported as written by the storage subsystem.
732@item readonly
733Enables exporting 9p share as a readonly mount for guests. By default
734read-write access is given.
735@item socket=@var{socket}
736Enables proxy filesystem driver to use passed socket file for
737communicating with virtfs-proxy-helper. Usually a helper like libvirt
738will create socketpair and pass one of the fds as sock_fd
739@item sock_fd
740Enables proxy filesystem driver to use passed 'sock_fd' as the socket
741descriptor for interfacing with virtfs-proxy-helper
742@end table
743ETEXI
744
745DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
746 "-virtfs_synth Create synthetic file system image\n",
747 QEMU_ARCH_ALL)
748STEXI
749@item -virtfs_synth
750@findex -virtfs_synth
751Create synthetic file system image
752ETEXI
753
754STEXI
755@end table
756ETEXI
757DEFHEADING()
758
759DEFHEADING(USB options:)
760STEXI
761@table @option
762ETEXI
763
764DEF("usb", 0, QEMU_OPTION_usb,
765 "-usb enable the USB driver (will be the default soon)\n",
766 QEMU_ARCH_ALL)
767STEXI
768@item -usb
769@findex -usb
770Enable the USB driver (will be the default soon)
771ETEXI
772
773DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
774 "-usbdevice name add the host or guest USB device 'name'\n",
775 QEMU_ARCH_ALL)
776STEXI
777
778@item -usbdevice @var{devname}
779@findex -usbdevice
780Add the USB device @var{devname}. @xref{usb_devices}.
781
782@table @option
783
784@item mouse
785Virtual Mouse. This will override the PS/2 mouse emulation when activated.
786
787@item tablet
788Pointer device that uses absolute coordinates (like a touchscreen). This
789means QEMU is able to report the mouse position without having to grab the
790mouse. Also overrides the PS/2 mouse emulation when activated.
791
792@item disk:[format=@var{format}]:@var{file}
793Mass storage device based on file. The optional @var{format} argument
794will be used rather than detecting the format. Can be used to specifiy
795@code{format=raw} to avoid interpreting an untrusted format header.
796
797@item host:@var{bus}.@var{addr}
798Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
799
800@item host:@var{vendor_id}:@var{product_id}
801Pass through the host device identified by @var{vendor_id}:@var{product_id}
802(Linux only).
803
804@item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
805Serial converter to host character device @var{dev}, see @code{-serial} for the
806available devices.
807
808@item braille
809Braille device. This will use BrlAPI to display the braille output on a real
810or fake device.
811
812@item net:@var{options}
813Network adapter that supports CDC ethernet and RNDIS protocols.
814
815@end table
816ETEXI
817
818STEXI
819@end table
820ETEXI
821DEFHEADING()
822
823DEFHEADING(Display options:)
824STEXI
825@table @option
826ETEXI
827
828DEF("display", HAS_ARG, QEMU_OPTION_display,
829 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
830 " [,window_close=on|off]|curses|none|\n"
831 " gtk[,grab_on_hover=on|off]|\n"
832 " vnc=<display>[,<optargs>]\n"
833 " select display type\n", QEMU_ARCH_ALL)
834STEXI
835@item -display @var{type}
836@findex -display
837Select type of display to use. This option is a replacement for the
838old style -sdl/-curses/... options. Valid values for @var{type} are
839@table @option
840@item sdl
841Display video output via SDL (usually in a separate graphics
842window; see the SDL documentation for other possibilities).
843@item curses
844Display video output via curses. For graphics device models which
845support a text mode, QEMU can display this output using a
846curses/ncurses interface. Nothing is displayed when the graphics
847device is in graphical mode or if the graphics device does not support
848a text mode. Generally only the VGA device models support text mode.
849@item none
850Do not display video output. The guest will still see an emulated
851graphics card, but its output will not be displayed to the QEMU
852user. This option differs from the -nographic option in that it
853only affects what is done with video output; -nographic also changes
854the destination of the serial and parallel port data.
855@item gtk
856Display video output in a GTK window. This interface provides drop-down
857menus and other UI elements to configure and control the VM during
858runtime.
859@item vnc
860Start a VNC server on display <arg>
861@end table
862ETEXI
863
864DEF("nographic", 0, QEMU_OPTION_nographic,
865 "-nographic disable graphical output and redirect serial I/Os to console\n",
866 QEMU_ARCH_ALL)
867STEXI
868@item -nographic
869@findex -nographic
870Normally, QEMU uses SDL to display the VGA output. With this option,
871you can totally disable graphical output so that QEMU is a simple
872command line application. The emulated serial port is redirected on
873the console and muxed with the monitor (unless redirected elsewhere
874explicitly). Therefore, you can still use QEMU to debug a Linux kernel
875with a serial console. Use @key{C-a h} for help on switching between
876the console and monitor.
877ETEXI
878
879DEF("curses", 0, QEMU_OPTION_curses,
880 "-curses use a curses/ncurses interface instead of SDL\n",
881 QEMU_ARCH_ALL)
882STEXI
883@item -curses
884@findex -curses
885Normally, QEMU uses SDL to display the VGA output. With this option,
886QEMU can display the VGA output when in text mode using a
887curses/ncurses interface. Nothing is displayed in graphical mode.
888ETEXI
889
890DEF("no-frame", 0, QEMU_OPTION_no_frame,
891 "-no-frame open SDL window without a frame and window decorations\n",
892 QEMU_ARCH_ALL)
893STEXI
894@item -no-frame
895@findex -no-frame
896Do not use decorations for SDL windows and start them using the whole
897available screen space. This makes the using QEMU in a dedicated desktop
898workspace more convenient.
899ETEXI
900
901DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
902 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
903 QEMU_ARCH_ALL)
904STEXI
905@item -alt-grab
906@findex -alt-grab
907Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
908affects the special keys (for fullscreen, monitor-mode switching, etc).
909ETEXI
910
911DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
912 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
913 QEMU_ARCH_ALL)
914STEXI
915@item -ctrl-grab
916@findex -ctrl-grab
917Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
918affects the special keys (for fullscreen, monitor-mode switching, etc).
919ETEXI
920
921DEF("no-quit", 0, QEMU_OPTION_no_quit,
922 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL)
923STEXI
924@item -no-quit
925@findex -no-quit
926Disable SDL window close capability.
927ETEXI
928
929DEF("sdl", 0, QEMU_OPTION_sdl,
930 "-sdl enable SDL\n", QEMU_ARCH_ALL)
931STEXI
932@item -sdl
933@findex -sdl
934Enable SDL.
935ETEXI
936
937DEF("spice", HAS_ARG, QEMU_OPTION_spice,
938 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
939 " [,x509-key-file=<file>][,x509-key-password=<file>]\n"
940 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
941 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6]\n"
942 " [,tls-ciphers=<list>]\n"
943 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
944 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
945 " [,sasl][,password=<secret>][,disable-ticketing]\n"
946 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
947 " [,jpeg-wan-compression=[auto|never|always]]\n"
948 " [,zlib-glz-wan-compression=[auto|never|always]]\n"
949 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
950 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
951 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
952 " enable spice\n"
953 " at least one of {port, tls-port} is mandatory\n",
954 QEMU_ARCH_ALL)
955STEXI
956@item -spice @var{option}[,@var{option}[,...]]
957@findex -spice
958Enable the spice remote desktop protocol. Valid options are
959
960@table @option
961
962@item port=<nr>
963Set the TCP port spice is listening on for plaintext channels.
964
965@item addr=<addr>
966Set the IP address spice is listening on. Default is any address.
967
968@item ipv4
969@item ipv6
970Force using the specified IP version.
971
972@item password=<secret>
973Set the password you need to authenticate.
974
975@item sasl
976Require that the client use SASL to authenticate with the spice.
977The exact choice of authentication method used is controlled from the
978system / user's SASL configuration file for the 'qemu' service. This
979is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
980unprivileged user, an environment variable SASL_CONF_PATH can be used
981to make it search alternate locations for the service config.
982While some SASL auth methods can also provide data encryption (eg GSSAPI),
983it is recommended that SASL always be combined with the 'tls' and
984'x509' settings to enable use of SSL and server certificates. This
985ensures a data encryption preventing compromise of authentication
986credentials.
987
988@item disable-ticketing
989Allow client connects without authentication.
990
991@item disable-copy-paste
992Disable copy paste between the client and the guest.
993
994@item disable-agent-file-xfer
995Disable spice-vdagent based file-xfer between the client and the guest.
996
997@item tls-port=<nr>
998Set the TCP port spice is listening on for encrypted channels.
999
1000@item x509-dir=<dir>
1001Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1002
1003@item x509-key-file=<file>
1004@item x509-key-password=<file>
1005@item x509-cert-file=<file>
1006@item x509-cacert-file=<file>
1007@item x509-dh-key-file=<file>
1008The x509 file names can also be configured individually.
1009
1010@item tls-ciphers=<list>
1011Specify which ciphers to use.
1012
1013@item tls-channel=[main|display|cursor|inputs|record|playback]
1014@item plaintext-channel=[main|display|cursor|inputs|record|playback]
1015Force specific channel to be used with or without TLS encryption. The
1016options can be specified multiple times to configure multiple
1017channels. The special name "default" can be used to set the default
1018mode. For channels which are not explicitly forced into one mode the
1019spice client is allowed to pick tls/plaintext as he pleases.
1020
1021@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1022Configure image compression (lossless).
1023Default is auto_glz.
1024
1025@item jpeg-wan-compression=[auto|never|always]
1026@item zlib-glz-wan-compression=[auto|never|always]
1027Configure wan image compression (lossy for slow links).
1028Default is auto.
1029
1030@item streaming-video=[off|all|filter]
1031Configure video stream detection. Default is filter.
1032
1033@item agent-mouse=[on|off]
1034Enable/disable passing mouse events via vdagent. Default is on.
1035
1036@item playback-compression=[on|off]
1037Enable/disable audio stream compression (using celt 0.5.1). Default is on.
1038
1039@item seamless-migration=[on|off]
1040Enable/disable spice seamless migration. Default is off.
1041
1042@end table
1043ETEXI
1044
1045DEF("portrait", 0, QEMU_OPTION_portrait,
1046 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
1047 QEMU_ARCH_ALL)
1048STEXI
1049@item -portrait
1050@findex -portrait
1051Rotate graphical output 90 deg left (only PXA LCD).
1052ETEXI
1053
1054DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1055 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
1056 QEMU_ARCH_ALL)
1057STEXI
1058@item -rotate @var{deg}
1059@findex -rotate
1060Rotate graphical output some deg left (only PXA LCD).
1061ETEXI
1062
1063DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1064 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|none]\n"
1065 " select video card type\n", QEMU_ARCH_ALL)
1066STEXI
1067@item -vga @var{type}
1068@findex -vga
1069Select type of VGA card to emulate. Valid values for @var{type} are
1070@table @option
1071@item cirrus
1072Cirrus Logic GD5446 Video card. All Windows versions starting from
1073Windows 95 should recognize and use this graphic card. For optimal
1074performances, use 16 bit color depth in the guest and the host OS.
1075(This one is the default)
1076@item std
1077Standard VGA card with Bochs VBE extensions. If your guest OS
1078supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1079to use high resolution modes (>= 1280x1024x16) then you should use
1080this option.
1081@item vmware
1082VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1083recent XFree86/XOrg server or Windows guest with a driver for this
1084card.
1085@item qxl
1086QXL paravirtual graphic card. It is VGA compatible (including VESA
10872.0 VBE support). Works best with qxl guest drivers installed though.
1088Recommended choice when using the spice protocol.
1089@item tcx
1090(sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1091sun4m machines and offers both 8-bit and 24-bit colour depths at a
1092fixed resolution of 1024x768.
1093@item cg3
1094(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1095for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1096resolutions aimed at people wishing to run older Solaris versions.
1097@item none
1098Disable VGA card.
1099@end table
1100ETEXI
1101
1102DEF("full-screen", 0, QEMU_OPTION_full_screen,
1103 "-full-screen start in full screen\n", QEMU_ARCH_ALL)
1104STEXI
1105@item -full-screen
1106@findex -full-screen
1107Start in full screen.
1108ETEXI
1109
1110DEF("g", 1, QEMU_OPTION_g ,
1111 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
1112 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1113STEXI
1114@item -g @var{width}x@var{height}[x@var{depth}]
1115@findex -g
1116Set the initial graphical resolution and depth (PPC, SPARC only).
1117ETEXI
1118
1119DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1120 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL)
1121STEXI
1122@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1123@findex -vnc
1124Normally, QEMU uses SDL to display the VGA output. With this option,
1125you can have QEMU listen on VNC display @var{display} and redirect the VGA
1126display over the VNC session. It is very useful to enable the usb
1127tablet device when using this option (option @option{-usbdevice
1128tablet}). When using the VNC display, you must use the @option{-k}
1129parameter to set the keyboard layout if you are not using en-us. Valid
1130syntax for the @var{display} is
1131
1132@table @option
1133
1134@item @var{host}:@var{d}
1135
1136TCP connections will only be allowed from @var{host} on display @var{d}.
1137By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1138be omitted in which case the server will accept connections from any host.
1139
1140@item unix:@var{path}
1141
1142Connections will be allowed over UNIX domain sockets where @var{path} is the
1143location of a unix socket to listen for connections on.
1144
1145@item none
1146
1147VNC is initialized but not started. The monitor @code{change} command
1148can be used to later start the VNC server.
1149
1150@end table
1151
1152Following the @var{display} value there may be one or more @var{option} flags
1153separated by commas. Valid options are
1154
1155@table @option
1156
1157@item reverse
1158
1159Connect to a listening VNC client via a ``reverse'' connection. The
1160client is specified by the @var{display}. For reverse network
1161connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1162is a TCP port number, not a display number.
1163
1164@item websocket
1165
1166Opens an additional TCP listening port dedicated to VNC Websocket connections.
1167By definition the Websocket port is 5700+@var{display}. If @var{host} is
1168specified connections will only be allowed from this host.
1169As an alternative the Websocket port could be specified by using
1170@code{websocket}=@var{port}.
1171TLS encryption for the Websocket connection is supported if the required
1172certificates are specified with the VNC option @option{x509}.
1173
1174@item password
1175
1176Require that password based authentication is used for client connections.
1177
1178The password must be set separately using the @code{set_password} command in
1179the @ref{pcsys_monitor}. The syntax to change your password is:
1180@code{set_password <protocol> <password>} where <protocol> could be either
1181"vnc" or "spice".
1182
1183If you would like to change <protocol> password expiration, you should use
1184@code{expire_password <protocol> <expiration-time>} where expiration time could
1185be one of the following options: now, never, +seconds or UNIX time of
1186expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1187to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1188date and time).
1189
1190You can also use keywords "now" or "never" for the expiration time to
1191allow <protocol> password to expire immediately or never expire.
1192
1193@item tls
1194
1195Require that client use TLS when communicating with the VNC server. This
1196uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1197attack. It is recommended that this option be combined with either the
1198@option{x509} or @option{x509verify} options.
1199
1200@item x509=@var{/path/to/certificate/dir}
1201
1202Valid if @option{tls} is specified. Require that x509 credentials are used
1203for negotiating the TLS session. The server will send its x509 certificate
1204to the client. It is recommended that a password be set on the VNC server
1205to provide authentication of the client when this is used. The path following
1206this option specifies where the x509 certificates are to be loaded from.
1207See the @ref{vnc_security} section for details on generating certificates.
1208
1209@item x509verify=@var{/path/to/certificate/dir}
1210
1211Valid if @option{tls} is specified. Require that x509 credentials are used
1212for negotiating the TLS session. The server will send its x509 certificate
1213to the client, and request that the client send its own x509 certificate.
1214The server will validate the client's certificate against the CA certificate,
1215and reject clients when validation fails. If the certificate authority is
1216trusted, this is a sufficient authentication mechanism. You may still wish
1217to set a password on the VNC server as a second authentication layer. The
1218path following this option specifies where the x509 certificates are to
1219be loaded from. See the @ref{vnc_security} section for details on generating
1220certificates.
1221
1222@item sasl
1223
1224Require that the client use SASL to authenticate with the VNC server.
1225The exact choice of authentication method used is controlled from the
1226system / user's SASL configuration file for the 'qemu' service. This
1227is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1228unprivileged user, an environment variable SASL_CONF_PATH can be used
1229to make it search alternate locations for the service config.
1230While some SASL auth methods can also provide data encryption (eg GSSAPI),
1231it is recommended that SASL always be combined with the 'tls' and
1232'x509' settings to enable use of SSL and server certificates. This
1233ensures a data encryption preventing compromise of authentication
1234credentials. See the @ref{vnc_security} section for details on using
1235SASL authentication.
1236
1237@item acl
1238
1239Turn on access control lists for checking of the x509 client certificate
1240and SASL party. For x509 certs, the ACL check is made against the
1241certificate's distinguished name. This is something that looks like
1242@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1243made against the username, which depending on the SASL plugin, may
1244include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1245When the @option{acl} flag is set, the initial access list will be
1246empty, with a @code{deny} policy. Thus no one will be allowed to
1247use the VNC server until the ACLs have been loaded. This can be
1248achieved using the @code{acl} monitor command.
1249
1250@item lossy
1251
1252Enable lossy compression methods (gradient, JPEG, ...). If this
1253option is set, VNC client may receive lossy framebuffer updates
1254depending on its encoding settings. Enabling this option can save
1255a lot of bandwidth at the expense of quality.
1256
1257@item non-adaptive
1258
1259Disable adaptive encodings. Adaptive encodings are enabled by default.
1260An adaptive encoding will try to detect frequently updated screen regions,
1261and send updates in these regions using a lossy encoding (like JPEG).
1262This can be really helpful to save bandwidth when playing videos. Disabling
1263adaptive encodings restores the original static behavior of encodings
1264like Tight.
1265
1266@item share=[allow-exclusive|force-shared|ignore]
1267
1268Set display sharing policy. 'allow-exclusive' allows clients to ask
1269for exclusive access. As suggested by the rfb spec this is
1270implemented by dropping other connections. Connecting multiple
1271clients in parallel requires all clients asking for a shared session
1272(vncviewer: -shared switch). This is the default. 'force-shared'
1273disables exclusive client access. Useful for shared desktop sessions,
1274where you don't want someone forgetting specify -shared disconnect
1275everybody else. 'ignore' completely ignores the shared flag and
1276allows everybody connect unconditionally. Doesn't conform to the rfb
1277spec but is traditional QEMU behavior.
1278
1279@end table
1280ETEXI
1281
1282STEXI
1283@end table
1284ETEXI
1285ARCHHEADING(, QEMU_ARCH_I386)
1286
1287ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1288STEXI
1289@table @option
1290ETEXI
1291
1292DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1293 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1294 QEMU_ARCH_I386)
1295STEXI
1296@item -win2k-hack
1297@findex -win2k-hack
1298Use it when installing Windows 2000 to avoid a disk full bug. After
1299Windows 2000 is installed, you no longer need this option (this option
1300slows down the IDE transfers).
1301ETEXI
1302
1303HXCOMM Deprecated by -rtc
1304DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1305
1306DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1307 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1308 QEMU_ARCH_I386)
1309STEXI
1310@item -no-fd-bootchk
1311@findex -no-fd-bootchk
1312Disable boot signature checking for floppy disks in BIOS. May
1313be needed to boot from old floppy disks.
1314ETEXI
1315
1316DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1317 "-no-acpi disable ACPI\n", QEMU_ARCH_I386)
1318STEXI
1319@item -no-acpi
1320@findex -no-acpi
1321Disable ACPI (Advanced Configuration and Power Interface) support. Use
1322it if your guest OS complains about ACPI problems (PC target machine
1323only).
1324ETEXI
1325
1326DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1327 "-no-hpet disable HPET\n", QEMU_ARCH_I386)
1328STEXI
1329@item -no-hpet
1330@findex -no-hpet
1331Disable HPET support.
1332ETEXI
1333
1334DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1335 "-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"
1336 " ACPI table description\n", QEMU_ARCH_I386)
1337STEXI
1338@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}]...]
1339@findex -acpitable
1340Add ACPI table with specified header fields and context from specified files.
1341For file=, take whole ACPI table from the specified files, including all
1342ACPI headers (possible overridden by other options).
1343For data=, only data
1344portion of the table is used, all header information is specified in the
1345command line.
1346ETEXI
1347
1348DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1349 "-smbios file=binary\n"
1350 " load SMBIOS entry from binary file\n"
1351 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d][,uefi=on|off]\n"
1352 " specify SMBIOS type 0 fields\n"
1353 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1354 " [,uuid=uuid][,sku=str][,family=str]\n"
1355 " specify SMBIOS type 1 fields\n", QEMU_ARCH_I386)
1356STEXI
1357@item -smbios file=@var{binary}
1358@findex -smbios
1359Load SMBIOS entry from binary file.
1360
1361@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1362Specify SMBIOS type 0 fields
1363
1364@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}]
1365Specify SMBIOS type 1 fields
1366ETEXI
1367
1368STEXI
1369@end table
1370ETEXI
1371DEFHEADING()
1372
1373DEFHEADING(Network options:)
1374STEXI
1375@table @option
1376ETEXI
1377
1378HXCOMM Legacy slirp options (now moved to -net user):
1379#ifdef CONFIG_SLIRP
1380DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1381DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1382DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1383#ifndef _WIN32
1384DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1385#endif
1386#endif
1387
1388DEF("net", HAS_ARG, QEMU_OPTION_net,
1389 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
1390 " create a new Network Interface Card and connect it to VLAN 'n'\n"
1391#ifdef CONFIG_SLIRP
1392 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=on|off]\n"
1393 " [,hostname=host][,dhcpstart=addr][,dns=addr][,dnssearch=domain][,tftp=dir]\n"
1394 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1395#ifndef _WIN32
1396 "[,smb=dir[,smbserver=addr]]\n"
1397#endif
1398 " connect the user mode network stack to VLAN 'n', configure its\n"
1399 " DHCP server and enabled optional services\n"
1400#endif
1401#ifdef _WIN32
1402 "-net tap[,vlan=n][,name=str],ifname=name\n"
1403 " connect the host TAP network interface to VLAN 'n'\n"
1404#else
1405 "-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"
1406 " connect the host TAP network interface to VLAN 'n'\n"
1407 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1408 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1409 " to deconfigure it\n"
1410 " use '[down]script=no' to disable script execution\n"
1411 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1412 " configure it\n"
1413 " use 'fd=h' to connect to an already opened TAP interface\n"
1414 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n"
1415 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
1416 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
1417 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1418 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1419 " use vhost=on to enable experimental in kernel accelerator\n"
1420 " (only has effect for virtio guests which use MSIX)\n"
1421 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1422 " use 'vhostfd=h' to connect to an already opened vhost net device\n"
1423 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n"
1424 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n"
1425 "-net bridge[,vlan=n][,name=str][,br=bridge][,helper=helper]\n"
1426 " connects a host TAP network interface to a host bridge device 'br'\n"
1427 " (default=" DEFAULT_BRIDGE_INTERFACE ") using the program 'helper'\n"
1428 " (default=" DEFAULT_BRIDGE_HELPER ")\n"
1429#endif
1430 "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n"
1431 " connect the vlan 'n' to another VLAN using a socket connection\n"
1432 "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1433 " connect the vlan 'n' to multicast maddr and port\n"
1434 " use 'localaddr=addr' to specify the host address to send packets from\n"
1435 "-net socket[,vlan=n][,name=str][,fd=h][,udp=host:port][,localaddr=host:port]\n"
1436 " connect the vlan 'n' to another VLAN using an UDP tunnel\n"
1437#ifdef CONFIG_VDE
1438 "-net vde[,vlan=n][,name=str][,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1439 " connect the vlan 'n' to port 'n' of a vde switch running\n"
1440 " on host and listening for incoming connections on 'socketpath'.\n"
1441 " Use group 'groupname' and mode 'octalmode' to change default\n"
1442 " ownership and permissions for communication port.\n"
1443#endif
1444#ifdef CONFIG_NETMAP
1445 "-net netmap,ifname=name[,devname=nmname]\n"
1446 " attach to the existing netmap-enabled network interface 'name', or to a\n"
1447 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n"
1448 " netmap device, defaults to '/dev/netmap')\n"
1449#endif
1450 "-net dump[,vlan=n][,file=f][,len=n]\n"
1451 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n"
1452 "-net none use it alone to have zero network devices. If no -net option\n"
1453 " is provided, the default is '-net nic -net user'\n", QEMU_ARCH_ALL)
1454DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1455 "-netdev ["
1456#ifdef CONFIG_SLIRP
1457 "user|"
1458#endif
1459 "tap|"
1460 "bridge|"
1461#ifdef CONFIG_VDE
1462 "vde|"
1463#endif
1464#ifdef CONFIG_NETMAP
1465 "netmap|"
1466#endif
1467 "vhost-user|"
1468 "socket|"
1469 "hubport],id=str[,option][,option][,...]\n", QEMU_ARCH_ALL)
1470STEXI
1471@item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1472@findex -net
1473Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1474= 0 is the default). The NIC is an e1000 by default on the PC
1475target. Optionally, the MAC address can be changed to @var{mac}, the
1476device address set to @var{addr} (PCI cards only),
1477and a @var{name} can be assigned for use in monitor commands.
1478Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1479that the card should have; this option currently only affects virtio cards; set
1480@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1481NIC is created. QEMU can emulate several different models of network card.
1482Valid values for @var{type} are
1483@code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1484@code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1485@code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1486Not all devices are supported on all targets. Use @code{-net nic,model=help}
1487for a list of available devices for your target.
1488
1489@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
1490@findex -netdev
1491@item -net user[,@var{option}][,@var{option}][,...]
1492Use the user mode network stack which requires no administrator
1493privilege to run. Valid options are:
1494
1495@table @option
1496@item vlan=@var{n}
1497Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1498
1499@item id=@var{id}
1500@item name=@var{name}
1501Assign symbolic name for use in monitor commands.
1502
1503@item net=@var{addr}[/@var{mask}]
1504Set IP network address the guest will see. Optionally specify the netmask,
1505either in the form a.b.c.d or as number of valid top-most bits. Default is
150610.0.2.0/24.
1507
1508@item host=@var{addr}
1509Specify the guest-visible address of the host. Default is the 2nd IP in the
1510guest network, i.e. x.x.x.2.
1511
1512@item restrict=on|off
1513If this option is enabled, the guest will be isolated, i.e. it will not be
1514able to contact the host and no guest IP packets will be routed over the host
1515to the outside. This option does not affect any explicitly set forwarding rules.
1516
1517@item hostname=@var{name}
1518Specifies the client hostname reported by the built-in DHCP server.
1519
1520@item dhcpstart=@var{addr}
1521Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1522is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1523
1524@item dns=@var{addr}
1525Specify the guest-visible address of the virtual nameserver. The address must
1526be different from the host address. Default is the 3rd IP in the guest network,
1527i.e. x.x.x.3.
1528
1529@item dnssearch=@var{domain}
1530Provides an entry for the domain-search list sent by the built-in
1531DHCP server. More than one domain suffix can be transmitted by specifying
1532this option multiple times. If supported, this will cause the guest to
1533automatically try to append the given domain suffix(es) in case a domain name
1534can not be resolved.
1535
1536Example:
1537@example
1538qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
1539@end example
1540
1541@item tftp=@var{dir}
1542When using the user mode network stack, activate a built-in TFTP
1543server. The files in @var{dir} will be exposed as the root of a TFTP server.
1544The TFTP client on the guest must be configured in binary mode (use the command
1545@code{bin} of the Unix TFTP client).
1546
1547@item bootfile=@var{file}
1548When using the user mode network stack, broadcast @var{file} as the BOOTP
1549filename. In conjunction with @option{tftp}, this can be used to network boot
1550a guest from a local directory.
1551
1552Example (using pxelinux):
1553@example
1554qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1555@end example
1556
1557@item smb=@var{dir}[,smbserver=@var{addr}]
1558When using the user mode network stack, activate a built-in SMB
1559server so that Windows OSes can access to the host files in @file{@var{dir}}
1560transparently. The IP address of the SMB server can be set to @var{addr}. By
1561default the 4th IP in the guest network is used, i.e. x.x.x.4.
1562
1563In the guest Windows OS, the line:
1564@example
156510.0.2.4 smbserver
1566@end example
1567must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1568or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1569
1570Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
1571
1572Note that a SAMBA server must be installed on the host OS.
1573QEMU was tested successfully with smbd versions from Red Hat 9,
1574Fedora Core 3 and OpenSUSE 11.x.
1575
1576@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1577Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1578the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1579@var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1580given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1581be bound to a specific host interface. If no connection type is set, TCP is
1582used. This option can be given multiple times.
1583
1584For example, to redirect host X11 connection from screen 1 to guest
1585screen 0, use the following:
1586
1587@example
1588# on the host
1589qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1590# this host xterm should open in the guest X11 server
1591xterm -display :1
1592@end example
1593
1594To redirect telnet connections from host port 5555 to telnet port on
1595the guest, use the following:
1596
1597@example
1598# on the host
1599qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
1600telnet localhost 5555
1601@end example
1602
1603Then when you use on the host @code{telnet localhost 5555}, you
1604connect to the guest telnet server.
1605
1606@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1607@item guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
1608Forward guest TCP connections to the IP address @var{server} on port @var{port}
1609to the character device @var{dev} or to a program executed by @var{cmd:command}
1610which gets spawned for each connection. This option can be given multiple times.
1611
1612You can either use a chardev directly and have that one used throughout QEMU's
1613lifetime, like in the following example:
1614
1615@example
1616# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
1617# the guest accesses it
1618qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...]
1619@end example
1620
1621Or you can execute a command on every TCP connection established by the guest,
1622so that QEMU behaves similar to an inetd process for that virtual server:
1623
1624@example
1625# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
1626# and connect the TCP stream to its stdin/stdout
1627qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
1628@end example
1629
1630@end table
1631
1632Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
1633processed and applied to -net user. Mixing them with the new configuration
1634syntax gives undefined results. Their use for new applications is discouraged
1635as they will be removed from future versions.
1636
1637@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1638@item -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1639Connect the host TAP network interface @var{name} to VLAN @var{n}.
1640
1641Use the network script @var{file} to configure it and the network script
1642@var{dfile} to deconfigure it. If @var{name} is not provided, the OS
1643automatically provides one. The default network configure script is
1644@file{/etc/qemu-ifup} and the default network deconfigure script is
1645@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
1646to disable script execution.
1647
1648If running QEMU as an unprivileged user, use the network helper
1649@var{helper} to configure the TAP interface. The default network
1650helper executable is @file{/path/to/qemu-bridge-helper}.
1651
1652@option{fd}=@var{h} can be used to specify the handle of an already
1653opened host TAP interface.
1654
1655Examples:
1656
1657@example
1658#launch a QEMU instance with the default network script
1659qemu-system-i386 linux.img -net nic -net tap
1660@end example
1661
1662@example
1663#launch a QEMU instance with two NICs, each one connected
1664#to a TAP device
1665qemu-system-i386 linux.img \
1666 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
1667 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
1668@end example
1669
1670@example
1671#launch a QEMU instance with the default network helper to
1672#connect a TAP device to bridge br0
1673qemu-system-i386 linux.img \
1674 -net nic -net tap,"helper=/path/to/qemu-bridge-helper"
1675@end example
1676
1677@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
1678@item -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
1679Connect a host TAP network interface to a host bridge device.
1680
1681Use the network helper @var{helper} to configure the TAP interface and
1682attach it to the bridge. The default network helper executable is
1683@file{/path/to/qemu-bridge-helper} and the default bridge
1684device is @file{br0}.
1685
1686Examples:
1687
1688@example
1689#launch a QEMU instance with the default network helper to
1690#connect a TAP device to bridge br0
1691qemu-system-i386 linux.img -net bridge -net nic,model=virtio
1692@end example
1693
1694@example
1695#launch a QEMU instance with the default network helper to
1696#connect a TAP device to bridge qemubr0
1697qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
1698@end example
1699
1700@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1701@item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1702
1703Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
1704machine using a TCP socket connection. If @option{listen} is
1705specified, QEMU waits for incoming connections on @var{port}
1706(@var{host} is optional). @option{connect} is used to connect to
1707another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
1708specifies an already opened TCP socket.
1709
1710Example:
1711@example
1712# launch a first QEMU instance
1713qemu-system-i386 linux.img \
1714 -net nic,macaddr=52:54:00:12:34:56 \
1715 -net socket,listen=:1234
1716# connect the VLAN 0 of this instance to the VLAN 0
1717# of the first instance
1718qemu-system-i386 linux.img \
1719 -net nic,macaddr=52:54:00:12:34:57 \
1720 -net socket,connect=127.0.0.1:1234
1721@end example
1722
1723@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1724@item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1725
1726Create a VLAN @var{n} shared with another QEMU virtual
1727machines using a UDP multicast socket, effectively making a bus for
1728every QEMU with same multicast address @var{maddr} and @var{port}.
1729NOTES:
1730@enumerate
1731@item
1732Several QEMU can be running on different hosts and share same bus (assuming
1733correct multicast setup for these hosts).
1734@item
1735mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
1736@url{http://user-mode-linux.sf.net}.
1737@item
1738Use @option{fd=h} to specify an already opened UDP multicast socket.
1739@end enumerate
1740
1741Example:
1742@example
1743# launch one QEMU instance
1744qemu-system-i386 linux.img \
1745 -net nic,macaddr=52:54:00:12:34:56 \
1746 -net socket,mcast=230.0.0.1:1234
1747# launch another QEMU instance on same "bus"
1748qemu-system-i386 linux.img \
1749 -net nic,macaddr=52:54:00:12:34:57 \
1750 -net socket,mcast=230.0.0.1:1234
1751# launch yet another QEMU instance on same "bus"
1752qemu-system-i386 linux.img \
1753 -net nic,macaddr=52:54:00:12:34:58 \
1754 -net socket,mcast=230.0.0.1:1234
1755@end example
1756
1757Example (User Mode Linux compat.):
1758@example
1759# launch QEMU instance (note mcast address selected
1760# is UML's default)
1761qemu-system-i386 linux.img \
1762 -net nic,macaddr=52:54:00:12:34:56 \
1763 -net socket,mcast=239.192.168.1:1102
1764# launch UML
1765/path/to/linux ubd0=/path/to/root_fs eth0=mcast
1766@end example
1767
1768Example (send packets from host's 1.2.3.4):
1769@example
1770qemu-system-i386 linux.img \
1771 -net nic,macaddr=52:54:00:12:34:56 \
1772 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
1773@end example
1774
1775@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1776@item -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1777Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
1778listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
1779and MODE @var{octalmode} to change default ownership and permissions for
1780communication port. This option is only available if QEMU has been compiled
1781with vde support enabled.
1782
1783Example:
1784@example
1785# launch vde switch
1786vde_switch -F -sock /tmp/myswitch
1787# launch QEMU instance
1788qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch
1789@end example
1790
1791@item -netdev hubport,id=@var{id},hubid=@var{hubid}
1792
1793Create a hub port on QEMU "vlan" @var{hubid}.
1794
1795The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single
1796netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the
1797required hub automatically.
1798
1799@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off]
1800
1801Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should
1802be a unix domain socket backed one. The vhost-user uses a specifically defined
1803protocol to pass vhost ioctl replacement messages to an application on the other
1804end of the socket. On non-MSIX guests, the feature can be forced with
1805@var{vhostforce}.
1806
1807Example:
1808@example
1809qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \
1810 -numa node,memdev=mem \
1811 -chardev socket,path=/path/to/socket \
1812 -netdev type=vhost-user,id=net0,chardev=chr0 \
1813 -device virtio-net-pci,netdev=net0
1814@end example
1815
1816@item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
1817Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
1818At most @var{len} bytes (64k by default) per packet are stored. The file format is
1819libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
1820
1821@item -net none
1822Indicate that no network devices should be configured. It is used to
1823override the default configuration (@option{-net nic -net user}) which
1824is activated if no @option{-net} options are provided.
1825ETEXI
1826
1827STEXI
1828@end table
1829ETEXI
1830DEFHEADING()
1831
1832DEFHEADING(Character device options:)
1833STEXI
1834
1835The general form of a character device option is:
1836@table @option
1837ETEXI
1838
1839DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
1840 "-chardev null,id=id[,mux=on|off]\n"
1841 "-chardev socket,id=id[,host=host],port=host[,to=to][,ipv4][,ipv6][,nodelay]\n"
1842 " [,server][,nowait][,telnet][,mux=on|off] (tcp)\n"
1843 "-chardev socket,id=id,path=path[,server][,nowait][,telnet],[mux=on|off] (unix)\n"
1844 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
1845 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
1846 "-chardev msmouse,id=id[,mux=on|off]\n"
1847 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
1848 " [,mux=on|off]\n"
1849 "-chardev ringbuf,id=id[,size=size]\n"
1850 "-chardev file,id=id,path=path[,mux=on|off]\n"
1851 "-chardev pipe,id=id,path=path[,mux=on|off]\n"
1852#ifdef _WIN32
1853 "-chardev console,id=id[,mux=on|off]\n"
1854 "-chardev serial,id=id,path=path[,mux=on|off]\n"
1855#else
1856 "-chardev pty,id=id[,mux=on|off]\n"
1857 "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n"
1858#endif
1859#ifdef CONFIG_BRLAPI
1860 "-chardev braille,id=id[,mux=on|off]\n"
1861#endif
1862#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
1863 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
1864 "-chardev serial,id=id,path=path[,mux=on|off]\n"
1865 "-chardev tty,id=id,path=path[,mux=on|off]\n"
1866#endif
1867#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
1868 "-chardev parallel,id=id,path=path[,mux=on|off]\n"
1869 "-chardev parport,id=id,path=path[,mux=on|off]\n"
1870#endif
1871#if defined(CONFIG_SPICE)
1872 "-chardev spicevmc,id=id,name=name[,debug=debug]\n"
1873 "-chardev spiceport,id=id,name=name[,debug=debug]\n"
1874#endif
1875 , QEMU_ARCH_ALL
1876)
1877
1878STEXI
1879@item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
1880@findex -chardev
1881Backend is one of:
1882@option{null},
1883@option{socket},
1884@option{udp},
1885@option{msmouse},
1886@option{vc},
1887@option{ringbuf},
1888@option{file},
1889@option{pipe},
1890@option{console},
1891@option{serial},
1892@option{pty},
1893@option{stdio},
1894@option{braille},
1895@option{tty},
1896@option{parallel},
1897@option{parport},
1898@option{spicevmc}.
1899@option{spiceport}.
1900The specific backend will determine the applicable options.
1901
1902All devices must have an id, which can be any string up to 127 characters long.
1903It is used to uniquely identify this device in other command line directives.
1904
1905A character device may be used in multiplexing mode by multiple front-ends.
1906The key sequence of @key{Control-a} and @key{c} will rotate the input focus
1907between attached front-ends. Specify @option{mux=on} to enable this mode.
1908
1909Options to each backend are described below.
1910
1911@item -chardev null ,id=@var{id}
1912A void device. This device will not emit any data, and will drop any data it
1913receives. The null backend does not take any options.
1914
1915@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet]
1916
1917Create a two-way stream socket, which can be either a TCP or a unix socket. A
1918unix socket will be created if @option{path} is specified. Behaviour is
1919undefined if TCP options are specified for a unix socket.
1920
1921@option{server} specifies that the socket shall be a listening socket.
1922
1923@option{nowait} specifies that QEMU should not block waiting for a client to
1924connect to a listening socket.
1925
1926@option{telnet} specifies that traffic on the socket should interpret telnet
1927escape sequences.
1928
1929TCP and unix socket options are given below:
1930
1931@table @option
1932
1933@item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
1934
1935@option{host} for a listening socket specifies the local address to be bound.
1936For a connecting socket species the remote host to connect to. @option{host} is
1937optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
1938
1939@option{port} for a listening socket specifies the local port to be bound. For a
1940connecting socket specifies the port on the remote host to connect to.
1941@option{port} can be given as either a port number or a service name.
1942@option{port} is required.
1943
1944@option{to} is only relevant to listening sockets. If it is specified, and
1945@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
1946to and including @option{to} until it succeeds. @option{to} must be specified
1947as a port number.
1948
1949@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1950If neither is specified the socket may use either protocol.
1951
1952@option{nodelay} disables the Nagle algorithm.
1953
1954@item unix options: path=@var{path}
1955
1956@option{path} specifies the local path of the unix socket. @option{path} is
1957required.
1958
1959@end table
1960
1961@item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
1962
1963Sends all traffic from the guest to a remote host over UDP.
1964
1965@option{host} specifies the remote host to connect to. If not specified it
1966defaults to @code{localhost}.
1967
1968@option{port} specifies the port on the remote host to connect to. @option{port}
1969is required.
1970
1971@option{localaddr} specifies the local address to bind to. If not specified it
1972defaults to @code{0.0.0.0}.
1973
1974@option{localport} specifies the local port to bind to. If not specified any
1975available local port will be used.
1976
1977@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1978If neither is specified the device may use either protocol.
1979
1980@item -chardev msmouse ,id=@var{id}
1981
1982Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
1983take any options.
1984
1985@item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
1986
1987Connect to a QEMU text console. @option{vc} may optionally be given a specific
1988size.
1989
1990@option{width} and @option{height} specify the width and height respectively of
1991the console, in pixels.
1992
1993@option{cols} and @option{rows} specify that the console be sized to fit a text
1994console with the given dimensions.
1995
1996@item -chardev ringbuf ,id=@var{id} [,size=@var{size}]
1997
1998Create a ring buffer with fixed size @option{size}.
1999@var{size} must be a power of two, and defaults to @code{64K}).
2000
2001@item -chardev file ,id=@var{id} ,path=@var{path}
2002
2003Log all traffic received from the guest to a file.
2004
2005@option{path} specifies the path of the file to be opened. This file will be
2006created if it does not already exist, and overwritten if it does. @option{path}
2007is required.
2008
2009@item -chardev pipe ,id=@var{id} ,path=@var{path}
2010
2011Create a two-way connection to the guest. The behaviour differs slightly between
2012Windows hosts and other hosts:
2013
2014On Windows, a single duplex pipe will be created at
2015@file{\\.pipe\@option{path}}.
2016
2017On other hosts, 2 pipes will be created called @file{@option{path}.in} and
2018@file{@option{path}.out}. Data written to @file{@option{path}.in} will be
2019received by the guest. Data written by the guest can be read from
2020@file{@option{path}.out}. QEMU will not create these fifos, and requires them to
2021be present.
2022
2023@option{path} forms part of the pipe path as described above. @option{path} is
2024required.
2025
2026@item -chardev console ,id=@var{id}
2027
2028Send traffic from the guest to QEMU's standard output. @option{console} does not
2029take any options.
2030
2031@option{console} is only available on Windows hosts.
2032
2033@item -chardev serial ,id=@var{id} ,path=@option{path}
2034
2035Send traffic from the guest to a serial device on the host.
2036
2037On Unix hosts serial will actually accept any tty device,
2038not only serial lines.
2039
2040@option{path} specifies the name of the serial device to open.
2041
2042@item -chardev pty ,id=@var{id}
2043
2044Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2045not take any options.
2046
2047@option{pty} is not available on Windows hosts.
2048
2049@item -chardev stdio ,id=@var{id} [,signal=on|off]
2050Connect to standard input and standard output of the QEMU process.
2051
2052@option{signal} controls if signals are enabled on the terminal, that includes
2053exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2054default, use @option{signal=off} to disable it.
2055
2056@option{stdio} is not available on Windows hosts.
2057
2058@item -chardev braille ,id=@var{id}
2059
2060Connect to a local BrlAPI server. @option{braille} does not take any options.
2061
2062@item -chardev tty ,id=@var{id} ,path=@var{path}
2063
2064@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2065DragonFlyBSD hosts. It is an alias for @option{serial}.
2066
2067@option{path} specifies the path to the tty. @option{path} is required.
2068
2069@item -chardev parallel ,id=@var{id} ,path=@var{path}
2070@item -chardev parport ,id=@var{id} ,path=@var{path}
2071
2072@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2073
2074Connect to a local parallel port.
2075
2076@option{path} specifies the path to the parallel port device. @option{path} is
2077required.
2078
2079@item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2080
2081@option{spicevmc} is only available when spice support is built in.
2082
2083@option{debug} debug level for spicevmc
2084
2085@option{name} name of spice channel to connect to
2086
2087Connect to a spice virtual machine channel, such as vdiport.
2088
2089@item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2090
2091@option{spiceport} is only available when spice support is built in.
2092
2093@option{debug} debug level for spicevmc
2094
2095@option{name} name of spice port to connect to
2096
2097Connect to a spice port, allowing a Spice client to handle the traffic
2098identified by a name (preferably a fqdn).
2099ETEXI
2100
2101STEXI
2102@end table
2103ETEXI
2104DEFHEADING()
2105
2106DEFHEADING(Device URL Syntax:)
2107STEXI
2108
2109In addition to using normal file images for the emulated storage devices,
2110QEMU can also use networked resources such as iSCSI devices. These are
2111specified using a special URL syntax.
2112
2113@table @option
2114@item iSCSI
2115iSCSI support allows QEMU to access iSCSI resources directly and use as
2116images for the guest storage. Both disk and cdrom images are supported.
2117
2118Syntax for specifying iSCSI LUNs is
2119``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
2120
2121By default qemu will use the iSCSI initiator-name
2122'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command
2123line or a configuration file.
2124
2125
2126Example (without authentication):
2127@example
2128qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
2129 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
2130 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2131@end example
2132
2133Example (CHAP username/password via URL):
2134@example
2135qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
2136@end example
2137
2138Example (CHAP username/password via environment variables):
2139@example
2140LIBISCSI_CHAP_USERNAME="user" \
2141LIBISCSI_CHAP_PASSWORD="password" \
2142qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2143@end example
2144
2145iSCSI support is an optional feature of QEMU and only available when
2146compiled and linked against libiscsi.
2147ETEXI
2148DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
2149 "-iscsi [user=user][,password=password]\n"
2150 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
2151 " [,initiator-name=initiator-iqn][,id=target-iqn]\n"
2152 " iSCSI session parameters\n", QEMU_ARCH_ALL)
2153STEXI
2154
2155iSCSI parameters such as username and password can also be specified via
2156a configuration file. See qemu-doc for more information and examples.
2157
2158@item NBD
2159QEMU supports NBD (Network Block Devices) both using TCP protocol as well
2160as Unix Domain Sockets.
2161
2162Syntax for specifying a NBD device using TCP
2163``nbd:<server-ip>:<port>[:exportname=<export>]''
2164
2165Syntax for specifying a NBD device using Unix Domain Sockets
2166``nbd:unix:<domain-socket>[:exportname=<export>]''
2167
2168
2169Example for TCP
2170@example
2171qemu-system-i386 --drive file=nbd:192.0.2.1:30000
2172@end example
2173
2174Example for Unix Domain Sockets
2175@example
2176qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket
2177@end example
2178
2179@item SSH
2180QEMU supports SSH (Secure Shell) access to remote disks.
2181
2182Examples:
2183@example
2184qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img
2185qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img
2186@end example
2187
2188Currently authentication must be done using ssh-agent. Other
2189authentication methods may be supported in future.
2190
2191@item Sheepdog
2192Sheepdog is a distributed storage system for QEMU.
2193QEMU supports using either local sheepdog devices or remote networked
2194devices.
2195
2196Syntax for specifying a sheepdog device
2197@example
2198sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag]
2199@end example
2200
2201Example
2202@example
2203qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine
2204@end example
2205
2206See also @url{http://http://www.osrg.net/sheepdog/}.
2207
2208@item GlusterFS
2209GlusterFS is an user space distributed file system.
2210QEMU supports the use of GlusterFS volumes for hosting VM disk images using
2211TCP, Unix Domain Sockets and RDMA transport protocols.
2212
2213Syntax for specifying a VM disk image on GlusterFS volume is
2214@example
2215gluster[+transport]://[server[:port]]/volname/image[?socket=...]
2216@end example
2217
2218
2219Example
2220@example
2221qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img
2222@end example
2223
2224See also @url{http://www.gluster.org}.
2225
2226@item HTTP/HTTPS/FTP/FTPS/TFTP
2227QEMU supports read-only access to files accessed over http(s), ftp(s) and tftp.
2228
2229Syntax using a single filename:
2230@example
2231<protocol>://[<username>[:<password>]@@]<host>/<path>
2232@end example
2233
2234where:
2235@table @option
2236@item protocol
2237'http', 'https', 'ftp', 'ftps', or 'tftp'.
2238
2239@item username
2240Optional username for authentication to the remote server.
2241
2242@item password
2243Optional password for authentication to the remote server.
2244
2245@item host
2246Address of the remote server.
2247
2248@item path
2249Path on the remote server, including any query string.
2250@end table
2251
2252The following options are also supported:
2253@table @option
2254@item url
2255The full URL when passing options to the driver explicitly.
2256
2257@item readahead
2258The amount of data to read ahead with each range request to the remote server.
2259This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it
2260does not have a suffix, it will be assumed to be in bytes. The value must be a
2261multiple of 512 bytes. It defaults to 256k.
2262
2263@item sslverify
2264Whether to verify the remote server's certificate when connecting over SSL. It
2265can have the value 'on' or 'off'. It defaults to 'on'.
2266@end table
2267
2268Note that when passing options to qemu explicitly, @option{driver} is the value
2269of <protocol>.
2270
2271Example: boot from a remote Fedora 20 live ISO image
2272@example
2273qemu-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
2274
2275qemu-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
2276@end example
2277
2278Example: boot from a remote Fedora 20 cloud image using a local overlay for
2279writes, copy-on-read, and a readahead of 64k
2280@example
2281qemu-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
2282
2283qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on
2284@end example
2285
2286Example: boot from an image stored on a VMware vSphere server with a self-signed
2287certificate using a local overlay for writes and a readahead of 64k
2288@example
2289qemu-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
2290
2291qemu-system-x86_64 -drive file=/tmp/test.qcow2
2292@end example
2293ETEXI
2294
2295STEXI
2296@end table
2297ETEXI
2298
2299DEFHEADING(Bluetooth(R) options:)
2300STEXI
2301@table @option
2302ETEXI
2303
2304DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
2305 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \
2306 "-bt hci,host[:id]\n" \
2307 " use host's HCI with the given name\n" \
2308 "-bt hci[,vlan=n]\n" \
2309 " emulate a standard HCI in virtual scatternet 'n'\n" \
2310 "-bt vhci[,vlan=n]\n" \
2311 " add host computer to virtual scatternet 'n' using VHCI\n" \
2312 "-bt device:dev[,vlan=n]\n" \
2313 " emulate a bluetooth device 'dev' in scatternet 'n'\n",
2314 QEMU_ARCH_ALL)
2315STEXI
2316@item -bt hci[...]
2317@findex -bt
2318Defines the function of the corresponding Bluetooth HCI. -bt options
2319are matched with the HCIs present in the chosen machine type. For
2320example when emulating a machine with only one HCI built into it, only
2321the first @code{-bt hci[...]} option is valid and defines the HCI's
2322logic. The Transport Layer is decided by the machine type. Currently
2323the machines @code{n800} and @code{n810} have one HCI and all other
2324machines have none.
2325
2326@anchor{bt-hcis}
2327The following three types are recognized:
2328
2329@table @option
2330@item -bt hci,null
2331(default) The corresponding Bluetooth HCI assumes no internal logic
2332and will not respond to any HCI commands or emit events.
2333
2334@item -bt hci,host[:@var{id}]
2335(@code{bluez} only) The corresponding HCI passes commands / events
2336to / from the physical HCI identified by the name @var{id} (default:
2337@code{hci0}) on the computer running QEMU. Only available on @code{bluez}
2338capable systems like Linux.
2339
2340@item -bt hci[,vlan=@var{n}]
2341Add a virtual, standard HCI that will participate in the Bluetooth
2342scatternet @var{n} (default @code{0}). Similarly to @option{-net}
2343VLANs, devices inside a bluetooth network @var{n} can only communicate
2344with other devices in the same network (scatternet).
2345@end table
2346
2347@item -bt vhci[,vlan=@var{n}]
2348(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2349to the host bluetooth stack instead of to the emulated target. This
2350allows the host and target machines to participate in a common scatternet
2351and communicate. Requires the Linux @code{vhci} driver installed. Can
2352be used as following:
2353
2354@example
2355qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2356@end example
2357
2358@item -bt device:@var{dev}[,vlan=@var{n}]
2359Emulate a bluetooth device @var{dev} and place it in network @var{n}
2360(default @code{0}). QEMU can only emulate one type of bluetooth devices
2361currently:
2362
2363@table @option
2364@item keyboard
2365Virtual wireless keyboard implementing the HIDP bluetooth profile.
2366@end table
2367ETEXI
2368
2369STEXI
2370@end table
2371ETEXI
2372DEFHEADING()
2373
2374#ifdef CONFIG_TPM
2375DEFHEADING(TPM device options:)
2376
2377DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
2378 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
2379 " use path to provide path to a character device; default is /dev/tpm0\n"
2380 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
2381 " not provided it will be searched for in /sys/class/misc/tpm?/device\n",
2382 QEMU_ARCH_ALL)
2383STEXI
2384
2385The general form of a TPM device option is:
2386@table @option
2387
2388@item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
2389@findex -tpmdev
2390Backend type must be:
2391@option{passthrough}.
2392
2393The specific backend type will determine the applicable options.
2394The @code{-tpmdev} option creates the TPM backend and requires a
2395@code{-device} option that specifies the TPM frontend interface model.
2396
2397Options to each backend are described below.
2398
2399Use 'help' to print all available TPM backend types.
2400@example
2401qemu -tpmdev help
2402@end example
2403
2404@item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path}
2405
2406(Linux-host only) Enable access to the host's TPM using the passthrough
2407driver.
2408
2409@option{path} specifies the path to the host's TPM device, i.e., on
2410a Linux host this would be @code{/dev/tpm0}.
2411@option{path} is optional and by default @code{/dev/tpm0} is used.
2412
2413@option{cancel-path} specifies the path to the host TPM device's sysfs
2414entry allowing for cancellation of an ongoing TPM command.
2415@option{cancel-path} is optional and by default QEMU will search for the
2416sysfs entry to use.
2417
2418Some notes about using the host's TPM with the passthrough driver:
2419
2420The TPM device accessed by the passthrough driver must not be
2421used by any other application on the host.
2422
2423Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
2424the VM's firmware (BIOS/UEFI) will not be able to initialize the
2425TPM again and may therefore not show a TPM-specific menu that would
2426otherwise allow the user to configure the TPM, e.g., allow the user to
2427enable/disable or activate/deactivate the TPM.
2428Further, if TPM ownership is released from within a VM then the host's TPM
2429will get disabled and deactivated. To enable and activate the
2430TPM again afterwards, the host has to be rebooted and the user is
2431required to enter the firmware's menu to enable and activate the TPM.
2432If the TPM is left disabled and/or deactivated most TPM commands will fail.
2433
2434To create a passthrough TPM use the following two options:
2435@example
2436-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
2437@end example
2438Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
2439@code{tpmdev=tpm0} in the device option.
2440
2441@end table
2442
2443ETEXI
2444
2445DEFHEADING()
2446
2447#endif
2448
2449DEFHEADING(Linux/Multiboot boot specific:)
2450STEXI
2451
2452When using these options, you can use a given Linux or Multiboot
2453kernel without installing it in the disk image. It can be useful
2454for easier testing of various kernels.
2455
2456@table @option
2457ETEXI
2458
2459DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
2460 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL)
2461STEXI
2462@item -kernel @var{bzImage}
2463@findex -kernel
2464Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2465or in multiboot format.
2466ETEXI
2467
2468DEF("append", HAS_ARG, QEMU_OPTION_append, \
2469 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL)
2470STEXI
2471@item -append @var{cmdline}
2472@findex -append
2473Use @var{cmdline} as kernel command line
2474ETEXI
2475
2476DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
2477 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL)
2478STEXI
2479@item -initrd @var{file}
2480@findex -initrd
2481Use @var{file} as initial ram disk.
2482
2483@item -initrd "@var{file1} arg=foo,@var{file2}"
2484
2485This syntax is only available with multiboot.
2486
2487Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
2488first module.
2489ETEXI
2490
2491DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
2492 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL)
2493STEXI
2494@item -dtb @var{file}
2495@findex -dtb
2496Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
2497on boot.
2498ETEXI
2499
2500STEXI
2501@end table
2502ETEXI
2503DEFHEADING()
2504
2505DEFHEADING(Debug/Expert options:)
2506STEXI
2507@table @option
2508ETEXI
2509
2510DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
2511 "-serial dev redirect the serial port to char device 'dev'\n",
2512 QEMU_ARCH_ALL)
2513STEXI
2514@item -serial @var{dev}
2515@findex -serial
2516Redirect the virtual serial port to host character device
2517@var{dev}. The default device is @code{vc} in graphical mode and
2518@code{stdio} in non graphical mode.
2519
2520This option can be used several times to simulate up to 4 serial
2521ports.
2522
2523Use @code{-serial none} to disable all serial ports.
2524
2525Available character devices are:
2526@table @option
2527@item vc[:@var{W}x@var{H}]
2528Virtual console. Optionally, a width and height can be given in pixel with
2529@example
2530vc:800x600
2531@end example
2532It is also possible to specify width or height in characters:
2533@example
2534vc:80Cx24C
2535@end example
2536@item pty
2537[Linux only] Pseudo TTY (a new PTY is automatically allocated)
2538@item none
2539No device is allocated.
2540@item null
2541void device
2542@item chardev:@var{id}
2543Use a named character device defined with the @code{-chardev} option.
2544@item /dev/XXX
2545[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
2546parameters are set according to the emulated ones.
2547@item /dev/parport@var{N}
2548[Linux only, parallel port only] Use host parallel port
2549@var{N}. Currently SPP and EPP parallel port features can be used.
2550@item file:@var{filename}
2551Write output to @var{filename}. No character can be read.
2552@item stdio
2553[Unix only] standard input/output
2554@item pipe:@var{filename}
2555name pipe @var{filename}
2556@item COM@var{n}
2557[Windows only] Use host serial port @var{n}
2558@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
2559This implements UDP Net Console.
2560When @var{remote_host} or @var{src_ip} are not specified
2561they default to @code{0.0.0.0}.
2562When not using a specified @var{src_port} a random port is automatically chosen.
2563
2564If you just want a simple readonly console you can use @code{netcat} or
2565@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
2566@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
2567will appear in the netconsole session.
2568
2569If you plan to send characters back via netconsole or you want to stop
2570and start QEMU a lot of times, you should have QEMU use the same
2571source port each time by using something like @code{-serial
2572udp::4555@@:4556} to QEMU. Another approach is to use a patched
2573version of netcat which can listen to a TCP port and send and receive
2574characters via udp. If you have a patched version of netcat which
2575activates telnet remote echo and single char transfer, then you can
2576use the following options to step up a netcat redirector to allow
2577telnet on port 5555 to access the QEMU port.
2578@table @code
2579@item QEMU Options:
2580-serial udp::4555@@:4556
2581@item netcat options:
2582-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
2583@item telnet options:
2584localhost 5555
2585@end table
2586
2587@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay]
2588The TCP Net Console has two modes of operation. It can send the serial
2589I/O to a location or wait for a connection from a location. By default
2590the TCP Net Console is sent to @var{host} at the @var{port}. If you use
2591the @var{server} option QEMU will wait for a client socket application
2592to connect to the port before continuing, unless the @code{nowait}
2593option was specified. The @code{nodelay} option disables the Nagle buffering
2594algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only
2595one TCP connection at a time is accepted. You can use @code{telnet} to
2596connect to the corresponding character device.
2597@table @code
2598@item Example to send tcp console to 192.168.0.2 port 4444
2599-serial tcp:192.168.0.2:4444
2600@item Example to listen and wait on port 4444 for connection
2601-serial tcp::4444,server
2602@item Example to not wait and listen on ip 192.168.0.100 port 4444
2603-serial tcp:192.168.0.100:4444,server,nowait
2604@end table
2605
2606@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
2607The telnet protocol is used instead of raw tcp sockets. The options
2608work the same as if you had specified @code{-serial tcp}. The
2609difference is that the port acts like a telnet server or client using
2610telnet option negotiation. This will also allow you to send the
2611MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
2612sequence. Typically in unix telnet you do it with Control-] and then
2613type "send break" followed by pressing the enter key.
2614
2615@item unix:@var{path}[,server][,nowait]
2616A unix domain socket is used instead of a tcp socket. The option works the
2617same as if you had specified @code{-serial tcp} except the unix domain socket
2618@var{path} is used for connections.
2619
2620@item mon:@var{dev_string}
2621This is a special option to allow the monitor to be multiplexed onto
2622another serial port. The monitor is accessed with key sequence of
2623@key{Control-a} and then pressing @key{c}.
2624@var{dev_string} should be any one of the serial devices specified
2625above. An example to multiplex the monitor onto a telnet server
2626listening on port 4444 would be:
2627@table @code
2628@item -serial mon:telnet::4444,server,nowait
2629@end table
2630When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
2631QEMU any more but will be passed to the guest instead.
2632
2633@item braille
2634Braille device. This will use BrlAPI to display the braille output on a real
2635or fake device.
2636
2637@item msmouse
2638Three button serial mouse. Configure the guest to use Microsoft protocol.
2639@end table
2640ETEXI
2641
2642DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
2643 "-parallel dev redirect the parallel port to char device 'dev'\n",
2644 QEMU_ARCH_ALL)
2645STEXI
2646@item -parallel @var{dev}
2647@findex -parallel
2648Redirect the virtual parallel port to host device @var{dev} (same
2649devices as the serial port). On Linux hosts, @file{/dev/parportN} can
2650be used to use hardware devices connected on the corresponding host
2651parallel port.
2652
2653This option can be used several times to simulate up to 3 parallel
2654ports.
2655
2656Use @code{-parallel none} to disable all parallel ports.
2657ETEXI
2658
2659DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
2660 "-monitor dev redirect the monitor to char device 'dev'\n",
2661 QEMU_ARCH_ALL)
2662STEXI
2663@item -monitor @var{dev}
2664@findex -monitor
2665Redirect the monitor to host device @var{dev} (same devices as the
2666serial port).
2667The default device is @code{vc} in graphical mode and @code{stdio} in
2668non graphical mode.
2669Use @code{-monitor none} to disable the default monitor.
2670ETEXI
2671DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
2672 "-qmp dev like -monitor but opens in 'control' mode\n",
2673 QEMU_ARCH_ALL)
2674STEXI
2675@item -qmp @var{dev}
2676@findex -qmp
2677Like -monitor but opens in 'control' mode.
2678ETEXI
2679
2680DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
2681 "-mon [chardev=]name[,mode=readline|control][,default]\n", QEMU_ARCH_ALL)
2682STEXI
2683@item -mon [chardev=]name[,mode=readline|control][,default]
2684@findex -mon
2685Setup monitor on chardev @var{name}.
2686ETEXI
2687
2688DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
2689 "-debugcon dev redirect the debug console to char device 'dev'\n",
2690 QEMU_ARCH_ALL)
2691STEXI
2692@item -debugcon @var{dev}
2693@findex -debugcon
2694Redirect the debug console to host device @var{dev} (same devices as the
2695serial port). The debug console is an I/O port which is typically port
26960xe9; writing to that I/O port sends output to this device.
2697The default device is @code{vc} in graphical mode and @code{stdio} in
2698non graphical mode.
2699ETEXI
2700
2701DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
2702 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL)
2703STEXI
2704@item -pidfile @var{file}
2705@findex -pidfile
2706Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
2707from a script.
2708ETEXI
2709
2710DEF("singlestep", 0, QEMU_OPTION_singlestep, \
2711 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL)
2712STEXI
2713@item -singlestep
2714@findex -singlestep
2715Run the emulation in single step mode.
2716ETEXI
2717
2718DEF("S", 0, QEMU_OPTION_S, \
2719 "-S freeze CPU at startup (use 'c' to start execution)\n",
2720 QEMU_ARCH_ALL)
2721STEXI
2722@item -S
2723@findex -S
2724Do not start CPU at startup (you must type 'c' in the monitor).
2725ETEXI
2726
2727DEF("realtime", HAS_ARG, QEMU_OPTION_realtime,
2728 "-realtime [mlock=on|off]\n"
2729 " run qemu with realtime features\n"
2730 " mlock=on|off controls mlock support (default: on)\n",
2731 QEMU_ARCH_ALL)
2732STEXI
2733@item -realtime mlock=on|off
2734@findex -realtime
2735Run qemu with realtime features.
2736mlocking qemu and guest memory can be enabled via @option{mlock=on}
2737(enabled by default).
2738ETEXI
2739
2740DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
2741 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL)
2742STEXI
2743@item -gdb @var{dev}
2744@findex -gdb
2745Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
2746connections will likely be TCP-based, but also UDP, pseudo TTY, or even
2747stdio are reasonable use case. The latter is allowing to start QEMU from
2748within gdb and establish the connection via a pipe:
2749@example
2750(gdb) target remote | exec qemu-system-i386 -gdb stdio ...
2751@end example
2752ETEXI
2753
2754DEF("s", 0, QEMU_OPTION_s, \
2755 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
2756 QEMU_ARCH_ALL)
2757STEXI
2758@item -s
2759@findex -s
2760Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
2761(@pxref{gdb_usage}).
2762ETEXI
2763
2764DEF("d", HAS_ARG, QEMU_OPTION_d, \
2765 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n",
2766 QEMU_ARCH_ALL)
2767STEXI
2768@item -d @var{item1}[,...]
2769@findex -d
2770Enable logging of specified items. Use '-d help' for a list of log items.
2771ETEXI
2772
2773DEF("D", HAS_ARG, QEMU_OPTION_D, \
2774 "-D logfile output log to logfile (default stderr)\n",
2775 QEMU_ARCH_ALL)
2776STEXI
2777@item -D @var{logfile}
2778@findex -D
2779Output log in @var{logfile} instead of to stderr
2780ETEXI
2781
2782DEF("L", HAS_ARG, QEMU_OPTION_L, \
2783 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
2784 QEMU_ARCH_ALL)
2785STEXI
2786@item -L @var{path}
2787@findex -L
2788Set the directory for the BIOS, VGA BIOS and keymaps.
2789ETEXI
2790
2791DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
2792 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL)
2793STEXI
2794@item -bios @var{file}
2795@findex -bios
2796Set the filename for the BIOS.
2797ETEXI
2798
2799DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
2800 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL)
2801STEXI
2802@item -enable-kvm
2803@findex -enable-kvm
2804Enable KVM full virtualization support. This option is only available
2805if KVM support is enabled when compiling.
2806ETEXI
2807
2808DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
2809 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL)
2810DEF("xen-create", 0, QEMU_OPTION_xen_create,
2811 "-xen-create create domain using xen hypercalls, bypassing xend\n"
2812 " warning: should not be used when xend is in use\n",
2813 QEMU_ARCH_ALL)
2814DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
2815 "-xen-attach attach to existing xen domain\n"
2816 " xend will use this when starting QEMU\n",
2817 QEMU_ARCH_ALL)
2818STEXI
2819@item -xen-domid @var{id}
2820@findex -xen-domid
2821Specify xen guest domain @var{id} (XEN only).
2822@item -xen-create
2823@findex -xen-create
2824Create domain using xen hypercalls, bypassing xend.
2825Warning: should not be used when xend is in use (XEN only).
2826@item -xen-attach
2827@findex -xen-attach
2828Attach to existing xen domain.
2829xend will use this when starting QEMU (XEN only).
2830ETEXI
2831
2832DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
2833 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL)
2834STEXI
2835@item -no-reboot
2836@findex -no-reboot
2837Exit instead of rebooting.
2838ETEXI
2839
2840DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
2841 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL)
2842STEXI
2843@item -no-shutdown
2844@findex -no-shutdown
2845Don't exit QEMU on guest shutdown, but instead only stop the emulation.
2846This allows for instance switching to monitor to commit changes to the
2847disk image.
2848ETEXI
2849
2850DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
2851 "-loadvm [tag|id]\n" \
2852 " start right away with a saved state (loadvm in monitor)\n",
2853 QEMU_ARCH_ALL)
2854STEXI
2855@item -loadvm @var{file}
2856@findex -loadvm
2857Start right away with a saved state (@code{loadvm} in monitor)
2858ETEXI
2859
2860#ifndef _WIN32
2861DEF("daemonize", 0, QEMU_OPTION_daemonize, \
2862 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
2863#endif
2864STEXI
2865@item -daemonize
2866@findex -daemonize
2867Daemonize the QEMU process after initialization. QEMU will not detach from
2868standard IO until it is ready to receive connections on any of its devices.
2869This option is a useful way for external programs to launch QEMU without having
2870to cope with initialization race conditions.
2871ETEXI
2872
2873DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
2874 "-option-rom rom load a file, rom, into the option ROM space\n",
2875 QEMU_ARCH_ALL)
2876STEXI
2877@item -option-rom @var{file}
2878@findex -option-rom
2879Load the contents of @var{file} as an option ROM.
2880This option is useful to load things like EtherBoot.
2881ETEXI
2882
2883DEF("clock", HAS_ARG, QEMU_OPTION_clock, \
2884 "-clock force the use of the given methods for timer alarm.\n" \
2885 " To see what timers are available use '-clock help'\n",
2886 QEMU_ARCH_ALL)
2887STEXI
2888@item -clock @var{method}
2889@findex -clock
2890Force the use of the given methods for timer alarm. To see what timers
2891are available use @code{-clock help}.
2892ETEXI
2893
2894HXCOMM Options deprecated by -rtc
2895DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
2896DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
2897
2898DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
2899 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
2900 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
2901 QEMU_ARCH_ALL)
2902
2903STEXI
2904
2905@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
2906@findex -rtc
2907Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
2908UTC or local time, respectively. @code{localtime} is required for correct date in
2909MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
2910format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
2911
2912By default the RTC is driven by the host system time. This allows using of the
2913RTC as accurate reference clock inside the guest, specifically if the host
2914time is smoothly following an accurate external reference clock, e.g. via NTP.
2915If you want to isolate the guest time from the host, you can set @option{clock}
2916to @code{rt} instead. To even prevent it from progressing during suspension,
2917you can set it to @code{vm}.
2918
2919Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
2920specifically with Windows' ACPI HAL. This option will try to figure out how
2921many timer interrupts were not processed by the Windows guest and will
2922re-inject them.
2923ETEXI
2924
2925DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
2926 "-icount [N|auto]\n" \
2927 " enable virtual instruction counter with 2^N clock ticks per\n" \
2928 " instruction\n", QEMU_ARCH_ALL)
2929STEXI
2930@item -icount [@var{N}|auto]
2931@findex -icount
2932Enable virtual instruction counter. The virtual cpu will execute one
2933instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
2934then the virtual cpu speed will be automatically adjusted to keep virtual
2935time within a few seconds of real time.
2936
2937Note that while this option can give deterministic behavior, it does not
2938provide cycle accurate emulation. Modern CPUs contain superscalar out of
2939order cores with complex cache hierarchies. The number of instructions
2940executed often has little or no correlation with actual performance.
2941ETEXI
2942
2943DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
2944 "-watchdog i6300esb|ib700\n" \
2945 " enable virtual hardware watchdog [default=none]\n",
2946 QEMU_ARCH_ALL)
2947STEXI
2948@item -watchdog @var{model}
2949@findex -watchdog
2950Create a virtual hardware watchdog device. Once enabled (by a guest
2951action), the watchdog must be periodically polled by an agent inside
2952the guest or else the guest will be restarted.
2953
2954The @var{model} is the model of hardware watchdog to emulate. Choices
2955for model are: @code{ib700} (iBASE 700) which is a very simple ISA
2956watchdog with a single timer, or @code{i6300esb} (Intel 6300ESB I/O
2957controller hub) which is a much more featureful PCI-based dual-timer
2958watchdog. Choose a model for which your guest has drivers.
2959
2960Use @code{-watchdog help} to list available hardware models. Only one
2961watchdog can be enabled for a guest.
2962ETEXI
2963
2964DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
2965 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
2966 " action when watchdog fires [default=reset]\n",
2967 QEMU_ARCH_ALL)
2968STEXI
2969@item -watchdog-action @var{action}
2970@findex -watchdog-action
2971
2972The @var{action} controls what QEMU will do when the watchdog timer
2973expires.
2974The default is
2975@code{reset} (forcefully reset the guest).
2976Other possible actions are:
2977@code{shutdown} (attempt to gracefully shutdown the guest),
2978@code{poweroff} (forcefully poweroff the guest),
2979@code{pause} (pause the guest),
2980@code{debug} (print a debug message and continue), or
2981@code{none} (do nothing).
2982
2983Note that the @code{shutdown} action requires that the guest responds
2984to ACPI signals, which it may not be able to do in the sort of
2985situations where the watchdog would have expired, and thus
2986@code{-watchdog-action shutdown} is not recommended for production use.
2987
2988Examples:
2989
2990@table @code
2991@item -watchdog i6300esb -watchdog-action pause
2992@item -watchdog ib700
2993@end table
2994ETEXI
2995
2996DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
2997 "-echr chr set terminal escape character instead of ctrl-a\n",
2998 QEMU_ARCH_ALL)
2999STEXI
3000
3001@item -echr @var{numeric_ascii_value}
3002@findex -echr
3003Change the escape character used for switching to the monitor when using
3004monitor and serial sharing. The default is @code{0x01} when using the
3005@code{-nographic} option. @code{0x01} is equal to pressing
3006@code{Control-a}. You can select a different character from the ascii
3007control keys where 1 through 26 map to Control-a through Control-z. For
3008instance you could use the either of the following to change the escape
3009character to Control-t.
3010@table @code
3011@item -echr 0x14
3012@item -echr 20
3013@end table
3014ETEXI
3015
3016DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
3017 "-virtioconsole c\n" \
3018 " set virtio console\n", QEMU_ARCH_ALL)
3019STEXI
3020@item -virtioconsole @var{c}
3021@findex -virtioconsole
3022Set virtio console.
3023
3024This option is maintained for backward compatibility.
3025
3026Please use @code{-device virtconsole} for the new way of invocation.
3027ETEXI
3028
3029DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
3030 "-show-cursor show cursor\n", QEMU_ARCH_ALL)
3031STEXI
3032@item -show-cursor
3033@findex -show-cursor
3034Show cursor.
3035ETEXI
3036
3037DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
3038 "-tb-size n set TB size\n", QEMU_ARCH_ALL)
3039STEXI
3040@item -tb-size @var{n}
3041@findex -tb-size
3042Set TB size.
3043ETEXI
3044
3045DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
3046 "-incoming p prepare for incoming migration, listen on port p\n",
3047 QEMU_ARCH_ALL)
3048STEXI
3049@item -incoming @var{port}
3050@findex -incoming
3051Prepare for incoming migration, listen on @var{port}.
3052ETEXI
3053
3054DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
3055 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL)
3056STEXI
3057@item -nodefaults
3058@findex -nodefaults
3059Don't create default devices. Normally, QEMU sets the default devices like serial
3060port, parallel port, virtual console, monitor device, VGA adapter, floppy and
3061CD-ROM drive and others. The @code{-nodefaults} option will disable all those
3062default devices.
3063ETEXI
3064
3065#ifndef _WIN32
3066DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
3067 "-chroot dir chroot to dir just before starting the VM\n",
3068 QEMU_ARCH_ALL)
3069#endif
3070STEXI
3071@item -chroot @var{dir}
3072@findex -chroot
3073Immediately before starting guest execution, chroot to the specified
3074directory. Especially useful in combination with -runas.
3075ETEXI
3076
3077#ifndef _WIN32
3078DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
3079 "-runas user change to user id user just before starting the VM\n",
3080 QEMU_ARCH_ALL)
3081#endif
3082STEXI
3083@item -runas @var{user}
3084@findex -runas
3085Immediately before starting guest execution, drop root privileges, switching
3086to the specified user.
3087ETEXI
3088
3089DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
3090 "-prom-env variable=value\n"
3091 " set OpenBIOS nvram variables\n",
3092 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3093STEXI
3094@item -prom-env @var{variable}=@var{value}
3095@findex -prom-env
3096Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
3097ETEXI
3098DEF("semihosting", 0, QEMU_OPTION_semihosting,
3099 "-semihosting semihosting mode\n",
3100 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32)
3101STEXI
3102@item -semihosting
3103@findex -semihosting
3104Semihosting mode (ARM, M68K, Xtensa only).
3105ETEXI
3106DEF("old-param", 0, QEMU_OPTION_old_param,
3107 "-old-param old param mode\n", QEMU_ARCH_ARM)
3108STEXI
3109@item -old-param
3110@findex -old-param (ARM)
3111Old param mode (ARM only).
3112ETEXI
3113
3114DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
3115 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n",
3116 QEMU_ARCH_ALL)
3117STEXI
3118@item -sandbox @var{arg}
3119@findex -sandbox
3120Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
3121disable it. The default is 'off'.
3122ETEXI
3123
3124DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
3125 "-readconfig <file>\n", QEMU_ARCH_ALL)
3126STEXI
3127@item -readconfig @var{file}
3128@findex -readconfig
3129Read device configuration from @var{file}. This approach is useful when you want to spawn
3130QEMU process with many command line options but you don't want to exceed the command line
3131character limit.
3132ETEXI
3133DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
3134 "-writeconfig <file>\n"
3135 " read/write config file\n", QEMU_ARCH_ALL)
3136STEXI
3137@item -writeconfig @var{file}
3138@findex -writeconfig
3139Write device configuration to @var{file}. The @var{file} can be either filename to save
3140command line and device configuration into file or dash @code{-}) character to print the
3141output to stdout. This can be later used as input file for @code{-readconfig} option.
3142ETEXI
3143DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig,
3144 "-nodefconfig\n"
3145 " do not load default config files at startup\n",
3146 QEMU_ARCH_ALL)
3147STEXI
3148@item -nodefconfig
3149@findex -nodefconfig
3150Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
3151The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
3152ETEXI
3153DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
3154 "-no-user-config\n"
3155 " do not load user-provided config files at startup\n",
3156 QEMU_ARCH_ALL)
3157STEXI
3158@item -no-user-config
3159@findex -no-user-config
3160The @code{-no-user-config} option makes QEMU not load any of the user-provided
3161config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config
3162files from @var{datadir}.
3163ETEXI
3164DEF("trace", HAS_ARG, QEMU_OPTION_trace,
3165 "-trace [events=<file>][,file=<file>]\n"
3166 " specify tracing options\n",
3167 QEMU_ARCH_ALL)
3168STEXI
3169HXCOMM This line is not accurate, as some sub-options are backend-specific but
3170HXCOMM HX does not support conditional compilation of text.
3171@item -trace [events=@var{file}][,file=@var{file}]
3172@findex -trace
3173
3174Specify tracing options.
3175
3176@table @option
3177@item events=@var{file}
3178Immediately enable events listed in @var{file}.
3179The file must contain one event name (as listed in the @var{trace-events} file)
3180per line.
3181This option is only available if QEMU has been compiled with
3182either @var{simple} or @var{stderr} tracing backend.
3183@item file=@var{file}
3184Log output traces to @var{file}.
3185
3186This option is only available if QEMU has been compiled with
3187the @var{simple} tracing backend.
3188@end table
3189ETEXI
3190
3191HXCOMM Internal use
3192DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL)
3193DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL)
3194
3195#ifdef __linux__
3196DEF("enable-fips", 0, QEMU_OPTION_enablefips,
3197 "-enable-fips enable FIPS 140-2 compliance\n",
3198 QEMU_ARCH_ALL)
3199#endif
3200STEXI
3201@item -enable-fips
3202@findex -enable-fips
3203Enable FIPS 140-2 compliance mode.
3204ETEXI
3205
3206HXCOMM Deprecated by -machine accel=tcg property
3207DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386)
3208
3209HXCOMM Deprecated by kvm-pit driver properties
3210DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection,
3211 "", QEMU_ARCH_I386)
3212
3213HXCOMM Deprecated (ignored)
3214DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386)
3215
3216HXCOMM Deprecated by -machine kernel_irqchip=on|off property
3217DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386)
3218
3219HXCOMM Deprecated (ignored)
3220DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL)
3221
3222DEF("object", HAS_ARG, QEMU_OPTION_object,
3223 "-object TYPENAME[,PROP1=VALUE1,...]\n"
3224 " create an new object of type TYPENAME setting properties\n"
3225 " in the order they are specified. Note that the 'id'\n"
3226 " property must be set. These objects are placed in the\n"
3227 " '/objects' path.\n",
3228 QEMU_ARCH_ALL)
3229STEXI
3230@item -object @var{typename}[,@var{prop1}=@var{value1},...]
3231@findex -object
3232Create an new object of type @var{typename} setting properties
3233in the order they are specified. Note that the 'id'
3234property must be set. These objects are placed in the
3235'/objects' path.
3236ETEXI
3237
3238DEF("msg", HAS_ARG, QEMU_OPTION_msg,
3239 "-msg timestamp[=on|off]\n"
3240 " change the format of messages\n"
3241 " on|off controls leading timestamps (default:on)\n",
3242 QEMU_ARCH_ALL)
3243STEXI
3244@item -msg timestamp[=on|off]
3245@findex -msg
3246prepend a timestamp to each log message.(default:on)
3247ETEXI
3248
3249HXCOMM This is the last statement. Insert new options before this line!
3250STEXI
3251@end table
3252ETEXI