1 HXCOMM Use DEFHEADING() to define headings in both help text and texi
2 HXCOMM Text between STEXI and ETEXI are copied to texi version and
3 HXCOMM discarded from C version
4 HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to
5 HXCOMM construct option structures, enums and help message for specified
7 HXCOMM HXCOMM can be used for comments, discarded from both texi and C
9 DEFHEADING(Standard options:)
14 DEF("help", 0, QEMU_OPTION_h,
15 "-h or -help display this help and exit\n", QEMU_ARCH_ALL)
22 DEF("version", 0, QEMU_OPTION_version,
23 "-version display version information and exit\n", QEMU_ARCH_ALL)
27 Display version information and exit
30 DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
31 "-machine [type=]name[,prop[=value][,...]]\n"
32 " selects emulated machine ('-machine help' for list)\n"
33 " property accel=accel1[:accel2[:...]] selects accelerator\n"
34 " supported accelerators are kvm, xen, tcg (default: tcg)\n"
35 " kernel_irqchip=on|off controls accelerated irqchip support\n"
36 " kvm_shadow_mem=size of KVM shadow MMU\n"
37 " dump-guest-core=on|off include guest memory in a core dump (default=on)\n"
38 " mem-merge=on|off controls memory merge support (default: on)\n",
41 @item -machine [type=]@var{name}[,prop=@var{value}[,...]]
43 Select the emulated machine by @var{name}. Use @code{-machine help} to list
44 available machines. Supported machine properties are:
46 @item accel=@var{accels1}[:@var{accels2}[:...]]
47 This is used to enable an accelerator. Depending on the target architecture,
48 kvm, xen, or tcg can be available. By default, tcg is used. If there is more
49 than one accelerator specified, the next one is used if the previous one fails
51 @item kernel_irqchip=on|off
52 Enables in-kernel irqchip support for the chosen accelerator when available.
53 @item kvm_shadow_mem=size
54 Defines the size of the KVM shadow MMU.
55 @item dump-guest-core=on|off
56 Include guest memory in a core dump. The default is on.
57 @item mem-merge=on|off
58 Enables or disables memory merge support. This feature, when supported by
59 the host, de-duplicates identical memory pages among VMs instances
64 HXCOMM Deprecated by -machine
65 DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL)
67 DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
68 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL)
70 @item -cpu @var{model}
72 Select CPU model (@code{-cpu help} for list and additional feature selection)
75 DEF("smp", HAS_ARG, QEMU_OPTION_smp,
76 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
77 " set the number of CPUs to 'n' [default=1]\n"
78 " maxcpus= maximum number of total cpus, including\n"
79 " offline CPUs for hotplug, etc\n"
80 " cores= number of CPU cores on one socket\n"
81 " threads= number of threads on one CPU core\n"
82 " sockets= number of discrete sockets in the system\n",
85 @item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
87 Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
88 CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
90 For the PC target, the number of @var{cores} per socket, the number
91 of @var{threads} per cores and the total number of @var{sockets} can be
92 specified. Missing values will be computed. If any on the three values is
93 given, the total number of CPUs @var{n} can be omitted. @var{maxcpus}
94 specifies the maximum number of hotpluggable CPUs.
97 DEF("numa", HAS_ARG, QEMU_OPTION_numa,
98 "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL)
100 @item -numa @var{opts}
102 Simulate a multi node NUMA system. If mem and cpus are omitted, resources
106 DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
107 "-add-fd fd=fd,set=set[,opaque=opaque]\n"
108 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL)
110 @item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}]
113 Add a file descriptor to an fd set. Valid options are:
117 This option defines the file descriptor of which a duplicate is added to fd set.
118 The file descriptor cannot be stdin, stdout, or stderr.
120 This option defines the ID of the fd set to add the file descriptor to.
121 @item opaque=@var{opaque}
122 This option defines a free-form string that can be used to describe @var{fd}.
125 You can open an image using pre-opened file descriptors from an fd set:
128 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
129 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
130 -drive file=/dev/fdset/2,index=0,media=disk
134 DEF("set", HAS_ARG, QEMU_OPTION_set,
135 "-set group.id.arg=value\n"
136 " set <arg> parameter for item <id> of type <group>\n"
137 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL)
139 @item -set @var{group}.@var{id}.@var{arg}=@var{value}
141 Set parameter @var{arg} for item @var{id} of type @var{group}\n"
144 DEF("global", HAS_ARG, QEMU_OPTION_global,
145 "-global driver.prop=value\n"
146 " set a global default for a driver property\n",
149 @item -global @var{driver}.@var{prop}=@var{value}
151 Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.:
154 qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk
157 In particular, you can use this to set driver properties for devices which are
158 created automatically by the machine model. To create a device which is not
159 created automatically and set properties on it, use -@option{device}.
162 DEF("boot", HAS_ARG, QEMU_OPTION_boot,
163 "-boot [order=drives][,once=drives][,menu=on|off]\n"
164 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
165 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
166 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n"
167 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n"
168 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n",
171 @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]
173 Specify boot order @var{drives} as a string of drive letters. Valid
174 drive letters depend on the target achitecture. The x86 PC uses: a, b
175 (floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
176 from network adapter 1-4), hard disk boot is the default. To apply a
177 particular boot order only on the first startup, specify it via
180 Interactive boot menus/prompts can be enabled via @option{menu=on} as far
181 as firmware/BIOS supports them. The default is non-interactive boot.
183 A splash picture could be passed to bios, enabling user to show it as logo,
184 when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
185 supports them. Currently Seabios for X86 system support it.
186 limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
187 format(true color). The resolution should be supported by the SVGA mode, so
188 the recommended is 320x240, 640x480, 800x640.
190 A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms
191 when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not
192 reboot, qemu passes '-1' to bios by default. Currently Seabios for X86
195 Do strict boot via @option{strict=on} as far as firmware/BIOS
196 supports it. This only effects when boot priority is changed by
197 bootindex options. The default is non-strict boot.
200 # try to boot from network first, then from hard disk
201 qemu-system-i386 -boot order=nc
202 # boot from CD-ROM first, switch back to default order after reboot
203 qemu-system-i386 -boot once=d
204 # boot with a splash picture for 5 seconds.
205 qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
208 Note: The legacy format '-boot @var{drives}' is still supported but its
209 use is discouraged as it may be removed from future versions.
212 DEF("m", HAS_ARG, QEMU_OPTION_m,
213 "-m[emory] [size=]megs[,slots=n,maxmem=size]\n"
214 " configure guest RAM\n"
215 " size: initial amount of guest memory (default: "
216 stringify(DEFAULT_RAM_SIZE) "MiB)\n"
217 " slots: number of hotplug slots (default: none)\n"
218 " maxmem: maximum amount of guest memory (default: none)\n",
221 @item -m [size=]@var{megs}
223 Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally,
224 a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or
225 gigabytes respectively. Optional pair @var{slots}, @var{maxmem} could be used
226 to set amount of hotluggable memory slots and possible maximum amount of memory.
229 DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
230 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
232 @item -mem-path @var{path}
234 Allocate guest RAM from a temporarily created file in @var{path}.
237 DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
238 "-mem-prealloc preallocate guest memory (use with -mem-path)\n",
242 @findex -mem-prealloc
243 Preallocate memory when using -mem-path.
246 DEF("k", HAS_ARG, QEMU_OPTION_k,
247 "-k language use keyboard layout (for example 'fr' for French)\n",
250 @item -k @var{language}
252 Use keyboard layout @var{language} (for example @code{fr} for
253 French). This option is only needed where it is not easy to get raw PC
254 keycodes (e.g. on Macs, with some X11 servers or with a VNC
255 display). You don't normally need to use it on PC/Linux or PC/Windows
258 The available layouts are:
260 ar de-ch es fo fr-ca hu ja mk no pt-br sv
261 da en-gb et fr fr-ch is lt nl pl ru th
262 de en-us fi fr-be hr it lv nl-be pt sl tr
265 The default is @code{en-us}.
269 DEF("audio-help", 0, QEMU_OPTION_audio_help,
270 "-audio-help print list of audio drivers and their options\n",
275 Will show the audio subsystem help: list of drivers, tunable
279 DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
280 "-soundhw c1,... enable audio support\n"
281 " and only specified sound cards (comma separated list)\n"
282 " use '-soundhw help' to get the list of supported cards\n"
283 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL)
285 @item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
287 Enable audio and selected sound hardware. Use 'help' to print all
288 available sound hardware.
291 qemu-system-i386 -soundhw sb16,adlib disk.img
292 qemu-system-i386 -soundhw es1370 disk.img
293 qemu-system-i386 -soundhw ac97 disk.img
294 qemu-system-i386 -soundhw hda disk.img
295 qemu-system-i386 -soundhw all disk.img
296 qemu-system-i386 -soundhw help
299 Note that Linux's i810_audio OSS kernel (for AC97) module might
300 require manually specifying clocking.
303 modprobe i810_audio clocking=48000
307 DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
308 "-balloon none disable balloon device\n"
309 "-balloon virtio[,addr=str]\n"
310 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL)
314 Disable balloon device.
315 @item -balloon virtio[,addr=@var{addr}]
316 Enable virtio balloon device (default), optionally with PCI address
320 DEF("device", HAS_ARG, QEMU_OPTION_device,
321 "-device driver[,prop[=value][,...]]\n"
322 " add device (based on driver)\n"
323 " prop=value,... sets driver properties\n"
324 " use '-device help' to print all possible drivers\n"
325 " use '-device driver,help' to print all possible properties\n",
328 @item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
330 Add device @var{driver}. @var{prop}=@var{value} sets driver
331 properties. Valid properties depend on the driver. To get help on
332 possible drivers and properties, use @code{-device help} and
333 @code{-device @var{driver},help}.
336 DEF("name", HAS_ARG, QEMU_OPTION_name,
337 "-name string1[,process=string2][,debug-threads=on|off]\n"
338 " set the name of the guest\n"
339 " string1 sets the window title and string2 the process name (on Linux)\n"
340 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n"
341 " NOTE: The thread names are for debugging and not a stable API.\n",
344 @item -name @var{name}
346 Sets the @var{name} of the guest.
347 This name will be displayed in the SDL window caption.
348 The @var{name} will also be used for the VNC server.
349 Also optionally set the top visible process name in Linux.
350 Naming of individual threads can also be enabled on Linux to aid debugging.
353 DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
354 "-uuid %08x-%04x-%04x-%04x-%012x\n"
355 " specify machine UUID\n", QEMU_ARCH_ALL)
357 @item -uuid @var{uuid}
367 DEFHEADING(Block device options:)
372 DEF("fda", HAS_ARG, QEMU_OPTION_fda,
373 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
374 DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
376 @item -fda @var{file}
377 @item -fdb @var{file}
380 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can
381 use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}).
384 DEF("hda", HAS_ARG, QEMU_OPTION_hda,
385 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
386 DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
387 DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
388 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
389 DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
391 @item -hda @var{file}
392 @item -hdb @var{file}
393 @item -hdc @var{file}
394 @item -hdd @var{file}
399 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
402 DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
403 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
406 @item -cdrom @var{file}
408 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
409 @option{-cdrom} at the same time). You can use the host CD-ROM by
410 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
413 DEF("drive", HAS_ARG, QEMU_OPTION_drive,
414 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
415 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
416 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
417 " [,serial=s][,addr=A][,rerror=ignore|stop|report]\n"
418 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n"
419 " [,readonly=on|off][,copy-on-read=on|off]\n"
420 " [,detect-zeroes=on|off|unmap]\n"
421 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n"
422 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n"
423 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n"
424 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n"
425 " [[,iops_size=is]]\n"
426 " use 'file' as a drive image\n", QEMU_ARCH_ALL)
428 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
431 Define a new drive. Valid options are:
434 @item file=@var{file}
435 This option defines which disk image (@pxref{disk_images}) to use with
436 this drive. If the filename contains comma, you must double it
437 (for instance, "file=my,,file" to use file "my,file").
439 Special files such as iSCSI devices can be specified using protocol
440 specific URLs. See the section for "Device URL Syntax" for more information.
441 @item if=@var{interface}
442 This option defines on which type on interface the drive is connected.
443 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio.
444 @item bus=@var{bus},unit=@var{unit}
445 These options define where is connected the drive by defining the bus number and
447 @item index=@var{index}
448 This option defines where is connected the drive by using an index in the list
449 of available connectors of a given interface type.
450 @item media=@var{media}
451 This option defines the type of the media: disk or cdrom.
452 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
453 These options have the same definition as they have in @option{-hdachs}.
454 @item snapshot=@var{snapshot}
455 @var{snapshot} is "on" or "off" and controls snapshot mode for the given drive
456 (see @option{-snapshot}).
457 @item cache=@var{cache}
458 @var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data.
460 @var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
461 @item discard=@var{discard}
462 @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.
463 @item format=@var{format}
464 Specify which disk @var{format} will be used rather than detecting
465 the format. Can be used to specifiy format=raw to avoid interpreting
466 an untrusted format header.
467 @item serial=@var{serial}
468 This option specifies the serial number to assign to the device.
469 @item addr=@var{addr}
470 Specify the controller's PCI address (if=virtio only).
471 @item werror=@var{action},rerror=@var{action}
472 Specify which @var{action} to take on write and read errors. Valid actions are:
473 "ignore" (ignore the error and try to continue), "stop" (pause QEMU),
474 "report" (report the error to the guest), "enospc" (pause QEMU only if the
475 host disk is full; report the error to the guest otherwise).
476 The default setting is @option{werror=enospc} and @option{rerror=report}.
478 Open drive @option{file} as read-only. Guest write attempts will fail.
479 @item copy-on-read=@var{copy-on-read}
480 @var{copy-on-read} is "on" or "off" and enables whether to copy read backing
481 file sectors into the image file.
482 @item detect-zeroes=@var{detect-zeroes}
483 @var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic
484 conversion of plain zero writes by the OS to driver specific optimized
485 zero write commands. You may even choose "unmap" if @var{discard} is set
486 to "unmap" to allow a zero write to be converted to an UNMAP operation.
489 By default, the @option{cache=writeback} mode is used. It will report data
490 writes as completed as soon as the data is present in the host page cache.
491 This is safe as long as your guest OS makes sure to correctly flush disk caches
492 where needed. If your guest OS does not handle volatile disk write caches
493 correctly and your host crashes or loses power, then the guest may experience
496 For such guests, you should consider using @option{cache=writethrough}. This
497 means that the host page cache will be used to read and write data, but write
498 notification will be sent to the guest only after QEMU has made sure to flush
499 each write to the disk. Be aware that this has a major impact on performance.
501 The host page cache can be avoided entirely with @option{cache=none}. This will
502 attempt to do disk IO directly to the guest's memory. QEMU may still perform
503 an internal copy of the data. Note that this is considered a writeback mode and
504 the guest OS must handle the disk write cache correctly in order to avoid data
505 corruption on host crashes.
507 The host page cache can be avoided while only sending write notifications to
508 the guest when the data has been flushed to the disk using
509 @option{cache=directsync}.
511 In case you don't care about data integrity over host failures, use
512 @option{cache=unsafe}. This option tells QEMU that it never needs to write any
513 data to the disk but can instead keep things in cache. If anything goes wrong,
514 like your host losing power, the disk storage getting disconnected accidentally,
515 etc. your image will most probably be rendered unusable. When using
516 the @option{-snapshot} option, unsafe caching is always used.
518 Copy-on-read avoids accessing the same backing file sectors repeatedly and is
519 useful when the backing file is over a slow network. By default copy-on-read
522 Instead of @option{-cdrom} you can use:
524 qemu-system-i386 -drive file=file,index=2,media=cdrom
527 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
530 qemu-system-i386 -drive file=file,index=0,media=disk
531 qemu-system-i386 -drive file=file,index=1,media=disk
532 qemu-system-i386 -drive file=file,index=2,media=disk
533 qemu-system-i386 -drive file=file,index=3,media=disk
536 You can open an image using pre-opened file descriptors from an fd set:
539 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
540 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
541 -drive file=/dev/fdset/2,index=0,media=disk
544 You can connect a CDROM to the slave of ide0:
546 qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
549 If you don't specify the "file=" argument, you define an empty drive:
551 qemu-system-i386 -drive if=ide,index=1,media=cdrom
554 You can connect a SCSI disk with unit ID 6 on the bus #0:
556 qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6
559 Instead of @option{-fda}, @option{-fdb}, you can use:
561 qemu-system-i386 -drive file=file,index=0,if=floppy
562 qemu-system-i386 -drive file=file,index=1,if=floppy
565 By default, @var{interface} is "ide" and @var{index} is automatically
568 qemu-system-i386 -drive file=a -drive file=b"
572 qemu-system-i386 -hda a -hdb b
576 DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
577 "-mtdblock file use 'file' as on-board Flash memory image\n",
580 @item -mtdblock @var{file}
582 Use @var{file} as on-board Flash memory image.
585 DEF("sd", HAS_ARG, QEMU_OPTION_sd,
586 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL)
590 Use @var{file} as SecureDigital card image.
593 DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
594 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL)
596 @item -pflash @var{file}
598 Use @var{file} as a parallel flash image.
601 DEF("snapshot", 0, QEMU_OPTION_snapshot,
602 "-snapshot write to temporary files instead of disk image files\n",
607 Write to temporary files instead of disk image files. In this case,
608 the raw disk image you use is not written back. You can however force
609 the write back by pressing @key{C-a s} (@pxref{disk_images}).
612 DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
613 "-hdachs c,h,s[,t]\n" \
614 " force hard disk 0 physical geometry and the optional BIOS\n" \
615 " translation (t=none or lba) (usually QEMU can guess them)\n",
618 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
620 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
621 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
622 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
623 all those parameters. This option is useful for old MS-DOS disk
627 DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
628 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
629 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
634 @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}]
636 Define a new file system device. Valid options are:
639 This option specifies the fs driver backend to use.
640 Currently "local", "handle" and "proxy" file system drivers are supported.
642 Specifies identifier for this device
643 @item path=@var{path}
644 Specifies the export path for the file system device. Files under
645 this path will be available to the 9p client on the guest.
646 @item security_model=@var{security_model}
647 Specifies the security model to be used for this export path.
648 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
649 In "passthrough" security model, files are stored using the same
650 credentials as they are created on the guest. This requires QEMU
651 to run as root. In "mapped-xattr" security model, some of the file
652 attributes like uid, gid, mode bits and link target are stored as
653 file attributes. For "mapped-file" these attributes are stored in the
654 hidden .virtfs_metadata directory. Directories exported by this security model cannot
655 interact with other unix tools. "none" security model is same as
656 passthrough except the sever won't report failures if it fails to
657 set file attributes like ownership. Security model is mandatory
658 only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
659 security model as a parameter.
660 @item writeout=@var{writeout}
661 This is an optional argument. The only supported value is "immediate".
662 This means that host page cache will be used to read and write data but
663 write notification will be sent to the guest only when the data has been
664 reported as written by the storage subsystem.
666 Enables exporting 9p share as a readonly mount for guests. By default
667 read-write access is given.
668 @item socket=@var{socket}
669 Enables proxy filesystem driver to use passed socket file for communicating
670 with virtfs-proxy-helper
671 @item sock_fd=@var{sock_fd}
672 Enables proxy filesystem driver to use passed socket descriptor for
673 communicating with virtfs-proxy-helper. Usually a helper like libvirt
674 will create socketpair and pass one of the fds as sock_fd
677 -fsdev option is used along with -device driver "virtio-9p-pci".
678 @item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
679 Options for virtio-9p-pci driver are:
682 Specifies the id value specified along with -fsdev option
683 @item mount_tag=@var{mount_tag}
684 Specifies the tag name to be used by the guest to mount this export point
689 DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
690 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
691 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
696 @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}]
699 The general form of a Virtual File system pass-through options are:
702 This option specifies the fs driver backend to use.
703 Currently "local", "handle" and "proxy" file system drivers are supported.
705 Specifies identifier for this device
706 @item path=@var{path}
707 Specifies the export path for the file system device. Files under
708 this path will be available to the 9p client on the guest.
709 @item security_model=@var{security_model}
710 Specifies the security model to be used for this export path.
711 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
712 In "passthrough" security model, files are stored using the same
713 credentials as they are created on the guest. This requires QEMU
714 to run as root. In "mapped-xattr" security model, some of the file
715 attributes like uid, gid, mode bits and link target are stored as
716 file attributes. For "mapped-file" these attributes are stored in the
717 hidden .virtfs_metadata directory. Directories exported by this security model cannot
718 interact with other unix tools. "none" security model is same as
719 passthrough except the sever won't report failures if it fails to
720 set file attributes like ownership. Security model is mandatory only
721 for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
722 model as a parameter.
723 @item writeout=@var{writeout}
724 This is an optional argument. The only supported value is "immediate".
725 This means that host page cache will be used to read and write data but
726 write notification will be sent to the guest only when the data has been
727 reported as written by the storage subsystem.
729 Enables exporting 9p share as a readonly mount for guests. By default
730 read-write access is given.
731 @item socket=@var{socket}
732 Enables proxy filesystem driver to use passed socket file for
733 communicating with virtfs-proxy-helper. Usually a helper like libvirt
734 will create socketpair and pass one of the fds as sock_fd
736 Enables proxy filesystem driver to use passed 'sock_fd' as the socket
737 descriptor for interfacing with virtfs-proxy-helper
741 DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
742 "-virtfs_synth Create synthetic file system image\n",
746 @findex -virtfs_synth
747 Create synthetic file system image
755 DEFHEADING(USB options:)
760 DEF("usb", 0, QEMU_OPTION_usb,
761 "-usb enable the USB driver (will be the default soon)\n",
766 Enable the USB driver (will be the default soon)
769 DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
770 "-usbdevice name add the host or guest USB device 'name'\n",
774 @item -usbdevice @var{devname}
776 Add the USB device @var{devname}. @xref{usb_devices}.
781 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
784 Pointer device that uses absolute coordinates (like a touchscreen). This
785 means QEMU is able to report the mouse position without having to grab the
786 mouse. Also overrides the PS/2 mouse emulation when activated.
788 @item disk:[format=@var{format}]:@var{file}
789 Mass storage device based on file. The optional @var{format} argument
790 will be used rather than detecting the format. Can be used to specifiy
791 @code{format=raw} to avoid interpreting an untrusted format header.
793 @item host:@var{bus}.@var{addr}
794 Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
796 @item host:@var{vendor_id}:@var{product_id}
797 Pass through the host device identified by @var{vendor_id}:@var{product_id}
800 @item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
801 Serial converter to host character device @var{dev}, see @code{-serial} for the
805 Braille device. This will use BrlAPI to display the braille output on a real
808 @item net:@var{options}
809 Network adapter that supports CDC ethernet and RNDIS protocols.
819 DEFHEADING(Display options:)
824 DEF("display", HAS_ARG, QEMU_OPTION_display,
825 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
826 " [,window_close=on|off]|curses|none|\n"
827 " gtk[,grab_on_hover=on|off]|\n"
828 " vnc=<display>[,<optargs>]\n"
829 " select display type\n", QEMU_ARCH_ALL)
831 @item -display @var{type}
833 Select type of display to use. This option is a replacement for the
834 old style -sdl/-curses/... options. Valid values for @var{type} are
837 Display video output via SDL (usually in a separate graphics
838 window; see the SDL documentation for other possibilities).
840 Display video output via curses. For graphics device models which
841 support a text mode, QEMU can display this output using a
842 curses/ncurses interface. Nothing is displayed when the graphics
843 device is in graphical mode or if the graphics device does not support
844 a text mode. Generally only the VGA device models support text mode.
846 Do not display video output. The guest will still see an emulated
847 graphics card, but its output will not be displayed to the QEMU
848 user. This option differs from the -nographic option in that it
849 only affects what is done with video output; -nographic also changes
850 the destination of the serial and parallel port data.
852 Display video output in a GTK window. This interface provides drop-down
853 menus and other UI elements to configure and control the VM during
856 Start a VNC server on display <arg>
860 DEF("nographic", 0, QEMU_OPTION_nographic,
861 "-nographic disable graphical output and redirect serial I/Os to console\n",
866 Normally, QEMU uses SDL to display the VGA output. With this option,
867 you can totally disable graphical output so that QEMU is a simple
868 command line application. The emulated serial port is redirected on
869 the console and muxed with the monitor (unless redirected elsewhere
870 explicitly). Therefore, you can still use QEMU to debug a Linux kernel
871 with a serial console. Use @key{C-a h} for help on switching between
872 the console and monitor.
875 DEF("curses", 0, QEMU_OPTION_curses,
876 "-curses use a curses/ncurses interface instead of SDL\n",
881 Normally, QEMU uses SDL to display the VGA output. With this option,
882 QEMU can display the VGA output when in text mode using a
883 curses/ncurses interface. Nothing is displayed in graphical mode.
886 DEF("no-frame", 0, QEMU_OPTION_no_frame,
887 "-no-frame open SDL window without a frame and window decorations\n",
892 Do not use decorations for SDL windows and start them using the whole
893 available screen space. This makes the using QEMU in a dedicated desktop
894 workspace more convenient.
897 DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
898 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
903 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
904 affects the special keys (for fullscreen, monitor-mode switching, etc).
907 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
908 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
913 Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
914 affects the special keys (for fullscreen, monitor-mode switching, etc).
917 DEF("no-quit", 0, QEMU_OPTION_no_quit,
918 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL)
922 Disable SDL window close capability.
925 DEF("sdl", 0, QEMU_OPTION_sdl,
926 "-sdl enable SDL\n", QEMU_ARCH_ALL)
933 DEF("spice", HAS_ARG, QEMU_OPTION_spice,
934 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
935 " [,x509-key-file=<file>][,x509-key-password=<file>]\n"
936 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
937 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6]\n"
938 " [,tls-ciphers=<list>]\n"
939 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
940 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
941 " [,sasl][,password=<secret>][,disable-ticketing]\n"
942 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
943 " [,jpeg-wan-compression=[auto|never|always]]\n"
944 " [,zlib-glz-wan-compression=[auto|never|always]]\n"
945 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
946 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
947 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
949 " at least one of {port, tls-port} is mandatory\n",
952 @item -spice @var{option}[,@var{option}[,...]]
954 Enable the spice remote desktop protocol. Valid options are
959 Set the TCP port spice is listening on for plaintext channels.
962 Set the IP address spice is listening on. Default is any address.
966 Force using the specified IP version.
968 @item password=<secret>
969 Set the password you need to authenticate.
972 Require that the client use SASL to authenticate with the spice.
973 The exact choice of authentication method used is controlled from the
974 system / user's SASL configuration file for the 'qemu' service. This
975 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
976 unprivileged user, an environment variable SASL_CONF_PATH can be used
977 to make it search alternate locations for the service config.
978 While some SASL auth methods can also provide data encryption (eg GSSAPI),
979 it is recommended that SASL always be combined with the 'tls' and
980 'x509' settings to enable use of SSL and server certificates. This
981 ensures a data encryption preventing compromise of authentication
984 @item disable-ticketing
985 Allow client connects without authentication.
987 @item disable-copy-paste
988 Disable copy paste between the client and the guest.
990 @item disable-agent-file-xfer
991 Disable spice-vdagent based file-xfer between the client and the guest.
994 Set the TCP port spice is listening on for encrypted channels.
997 Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
999 @item x509-key-file=<file>
1000 @item x509-key-password=<file>
1001 @item x509-cert-file=<file>
1002 @item x509-cacert-file=<file>
1003 @item x509-dh-key-file=<file>
1004 The x509 file names can also be configured individually.
1006 @item tls-ciphers=<list>
1007 Specify which ciphers to use.
1009 @item tls-channel=[main|display|cursor|inputs|record|playback]
1010 @item plaintext-channel=[main|display|cursor|inputs|record|playback]
1011 Force specific channel to be used with or without TLS encryption. The
1012 options can be specified multiple times to configure multiple
1013 channels. The special name "default" can be used to set the default
1014 mode. For channels which are not explicitly forced into one mode the
1015 spice client is allowed to pick tls/plaintext as he pleases.
1017 @item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1018 Configure image compression (lossless).
1019 Default is auto_glz.
1021 @item jpeg-wan-compression=[auto|never|always]
1022 @item zlib-glz-wan-compression=[auto|never|always]
1023 Configure wan image compression (lossy for slow links).
1026 @item streaming-video=[off|all|filter]
1027 Configure video stream detection. Default is filter.
1029 @item agent-mouse=[on|off]
1030 Enable/disable passing mouse events via vdagent. Default is on.
1032 @item playback-compression=[on|off]
1033 Enable/disable audio stream compression (using celt 0.5.1). Default is on.
1035 @item seamless-migration=[on|off]
1036 Enable/disable spice seamless migration. Default is off.
1041 DEF("portrait", 0, QEMU_OPTION_portrait,
1042 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
1047 Rotate graphical output 90 deg left (only PXA LCD).
1050 DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1051 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
1054 @item -rotate @var{deg}
1056 Rotate graphical output some deg left (only PXA LCD).
1059 DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1060 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|none]\n"
1061 " select video card type\n", QEMU_ARCH_ALL)
1063 @item -vga @var{type}
1065 Select type of VGA card to emulate. Valid values for @var{type} are
1068 Cirrus Logic GD5446 Video card. All Windows versions starting from
1069 Windows 95 should recognize and use this graphic card. For optimal
1070 performances, use 16 bit color depth in the guest and the host OS.
1071 (This one is the default)
1073 Standard VGA card with Bochs VBE extensions. If your guest OS
1074 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1075 to use high resolution modes (>= 1280x1024x16) then you should use
1078 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1079 recent XFree86/XOrg server or Windows guest with a driver for this
1082 QXL paravirtual graphic card. It is VGA compatible (including VESA
1083 2.0 VBE support). Works best with qxl guest drivers installed though.
1084 Recommended choice when using the spice protocol.
1086 (sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1087 sun4m machines and offers both 8-bit and 24-bit colour depths at a
1088 fixed resolution of 1024x768.
1090 (sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1091 for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1092 resolutions aimed at people wishing to run older Solaris versions.
1098 DEF("full-screen", 0, QEMU_OPTION_full_screen,
1099 "-full-screen start in full screen\n", QEMU_ARCH_ALL)
1102 @findex -full-screen
1103 Start in full screen.
1106 DEF("g", 1, QEMU_OPTION_g ,
1107 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
1108 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1110 @item -g @var{width}x@var{height}[x@var{depth}]
1112 Set the initial graphical resolution and depth (PPC, SPARC only).
1115 DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1116 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL)
1118 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1120 Normally, QEMU uses SDL to display the VGA output. With this option,
1121 you can have QEMU listen on VNC display @var{display} and redirect the VGA
1122 display over the VNC session. It is very useful to enable the usb
1123 tablet device when using this option (option @option{-usbdevice
1124 tablet}). When using the VNC display, you must use the @option{-k}
1125 parameter to set the keyboard layout if you are not using en-us. Valid
1126 syntax for the @var{display} is
1130 @item @var{host}:@var{d}
1132 TCP connections will only be allowed from @var{host} on display @var{d}.
1133 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1134 be omitted in which case the server will accept connections from any host.
1136 @item unix:@var{path}
1138 Connections will be allowed over UNIX domain sockets where @var{path} is the
1139 location of a unix socket to listen for connections on.
1143 VNC is initialized but not started. The monitor @code{change} command
1144 can be used to later start the VNC server.
1148 Following the @var{display} value there may be one or more @var{option} flags
1149 separated by commas. Valid options are
1155 Connect to a listening VNC client via a ``reverse'' connection. The
1156 client is specified by the @var{display}. For reverse network
1157 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1158 is a TCP port number, not a display number.
1162 Opens an additional TCP listening port dedicated to VNC Websocket connections.
1163 By definition the Websocket port is 5700+@var{display}. If @var{host} is
1164 specified connections will only be allowed from this host.
1165 As an alternative the Websocket port could be specified by using
1166 @code{websocket}=@var{port}.
1167 TLS encryption for the Websocket connection is supported if the required
1168 certificates are specified with the VNC option @option{x509}.
1172 Require that password based authentication is used for client connections.
1174 The password must be set separately using the @code{set_password} command in
1175 the @ref{pcsys_monitor}. The syntax to change your password is:
1176 @code{set_password <protocol> <password>} where <protocol> could be either
1179 If you would like to change <protocol> password expiration, you should use
1180 @code{expire_password <protocol> <expiration-time>} where expiration time could
1181 be one of the following options: now, never, +seconds or UNIX time of
1182 expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1183 to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1186 You can also use keywords "now" or "never" for the expiration time to
1187 allow <protocol> password to expire immediately or never expire.
1191 Require that client use TLS when communicating with the VNC server. This
1192 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1193 attack. It is recommended that this option be combined with either the
1194 @option{x509} or @option{x509verify} options.
1196 @item x509=@var{/path/to/certificate/dir}
1198 Valid if @option{tls} is specified. Require that x509 credentials are used
1199 for negotiating the TLS session. The server will send its x509 certificate
1200 to the client. It is recommended that a password be set on the VNC server
1201 to provide authentication of the client when this is used. The path following
1202 this option specifies where the x509 certificates are to be loaded from.
1203 See the @ref{vnc_security} section for details on generating certificates.
1205 @item x509verify=@var{/path/to/certificate/dir}
1207 Valid if @option{tls} is specified. Require that x509 credentials are used
1208 for negotiating the TLS session. The server will send its x509 certificate
1209 to the client, and request that the client send its own x509 certificate.
1210 The server will validate the client's certificate against the CA certificate,
1211 and reject clients when validation fails. If the certificate authority is
1212 trusted, this is a sufficient authentication mechanism. You may still wish
1213 to set a password on the VNC server as a second authentication layer. The
1214 path following this option specifies where the x509 certificates are to
1215 be loaded from. See the @ref{vnc_security} section for details on generating
1220 Require that the client use SASL to authenticate with the VNC server.
1221 The exact choice of authentication method used is controlled from the
1222 system / user's SASL configuration file for the 'qemu' service. This
1223 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1224 unprivileged user, an environment variable SASL_CONF_PATH can be used
1225 to make it search alternate locations for the service config.
1226 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1227 it is recommended that SASL always be combined with the 'tls' and
1228 'x509' settings to enable use of SSL and server certificates. This
1229 ensures a data encryption preventing compromise of authentication
1230 credentials. See the @ref{vnc_security} section for details on using
1231 SASL authentication.
1235 Turn on access control lists for checking of the x509 client certificate
1236 and SASL party. For x509 certs, the ACL check is made against the
1237 certificate's distinguished name. This is something that looks like
1238 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1239 made against the username, which depending on the SASL plugin, may
1240 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1241 When the @option{acl} flag is set, the initial access list will be
1242 empty, with a @code{deny} policy. Thus no one will be allowed to
1243 use the VNC server until the ACLs have been loaded. This can be
1244 achieved using the @code{acl} monitor command.
1248 Enable lossy compression methods (gradient, JPEG, ...). If this
1249 option is set, VNC client may receive lossy framebuffer updates
1250 depending on its encoding settings. Enabling this option can save
1251 a lot of bandwidth at the expense of quality.
1255 Disable adaptive encodings. Adaptive encodings are enabled by default.
1256 An adaptive encoding will try to detect frequently updated screen regions,
1257 and send updates in these regions using a lossy encoding (like JPEG).
1258 This can be really helpful to save bandwidth when playing videos. Disabling
1259 adaptive encodings restores the original static behavior of encodings
1262 @item share=[allow-exclusive|force-shared|ignore]
1264 Set display sharing policy. 'allow-exclusive' allows clients to ask
1265 for exclusive access. As suggested by the rfb spec this is
1266 implemented by dropping other connections. Connecting multiple
1267 clients in parallel requires all clients asking for a shared session
1268 (vncviewer: -shared switch). This is the default. 'force-shared'
1269 disables exclusive client access. Useful for shared desktop sessions,
1270 where you don't want someone forgetting specify -shared disconnect
1271 everybody else. 'ignore' completely ignores the shared flag and
1272 allows everybody connect unconditionally. Doesn't conform to the rfb
1273 spec but is traditional QEMU behavior.
1281 ARCHHEADING(, QEMU_ARCH_I386)
1283 ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1288 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1289 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1294 Use it when installing Windows 2000 to avoid a disk full bug. After
1295 Windows 2000 is installed, you no longer need this option (this option
1296 slows down the IDE transfers).
1299 HXCOMM Deprecated by -rtc
1300 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1302 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1303 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1306 @item -no-fd-bootchk
1307 @findex -no-fd-bootchk
1308 Disable boot signature checking for floppy disks in BIOS. May
1309 be needed to boot from old floppy disks.
1312 DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1313 "-no-acpi disable ACPI\n", QEMU_ARCH_I386)
1317 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1318 it if your guest OS complains about ACPI problems (PC target machine
1322 DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1323 "-no-hpet disable HPET\n", QEMU_ARCH_I386)
1327 Disable HPET support.
1330 DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1331 "-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"
1332 " ACPI table description\n", QEMU_ARCH_I386)
1334 @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}]...]
1336 Add ACPI table with specified header fields and context from specified files.
1337 For file=, take whole ACPI table from the specified files, including all
1338 ACPI headers (possible overridden by other options).
1339 For data=, only data
1340 portion of the table is used, all header information is specified in the
1344 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1345 "-smbios file=binary\n"
1346 " load SMBIOS entry from binary file\n"
1347 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d][,uefi=on|off]\n"
1348 " specify SMBIOS type 0 fields\n"
1349 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1350 " [,uuid=uuid][,sku=str][,family=str]\n"
1351 " specify SMBIOS type 1 fields\n", QEMU_ARCH_I386)
1353 @item -smbios file=@var{binary}
1355 Load SMBIOS entry from binary file.
1357 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1358 Specify SMBIOS type 0 fields
1360 @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}]
1361 Specify SMBIOS type 1 fields
1369 DEFHEADING(Network options:)
1374 HXCOMM Legacy slirp options (now moved to -net user):
1376 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1377 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1378 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1380 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1384 DEF("net", HAS_ARG, QEMU_OPTION_net,
1385 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
1386 " create a new Network Interface Card and connect it to VLAN 'n'\n"
1388 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=on|off]\n"
1389 " [,hostname=host][,dhcpstart=addr][,dns=addr][,dnssearch=domain][,tftp=dir]\n"
1390 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1392 "[,smb=dir[,smbserver=addr]]\n"
1394 " connect the user mode network stack to VLAN 'n', configure its\n"
1395 " DHCP server and enabled optional services\n"
1398 "-net tap[,vlan=n][,name=str],ifname=name\n"
1399 " connect the host TAP network interface to VLAN 'n'\n"
1401 "-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"
1402 " connect the host TAP network interface to VLAN 'n'\n"
1403 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1404 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1405 " to deconfigure it\n"
1406 " use '[down]script=no' to disable script execution\n"
1407 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1409 " use 'fd=h' to connect to an already opened TAP interface\n"
1410 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n"
1411 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
1412 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
1413 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1414 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1415 " use vhost=on to enable experimental in kernel accelerator\n"
1416 " (only has effect for virtio guests which use MSIX)\n"
1417 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1418 " use 'vhostfd=h' to connect to an already opened vhost net device\n"
1419 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n"
1420 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n"
1421 "-net bridge[,vlan=n][,name=str][,br=bridge][,helper=helper]\n"
1422 " connects a host TAP network interface to a host bridge device 'br'\n"
1423 " (default=" DEFAULT_BRIDGE_INTERFACE ") using the program 'helper'\n"
1424 " (default=" DEFAULT_BRIDGE_HELPER ")\n"
1426 "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n"
1427 " connect the vlan 'n' to another VLAN using a socket connection\n"
1428 "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1429 " connect the vlan 'n' to multicast maddr and port\n"
1430 " use 'localaddr=addr' to specify the host address to send packets from\n"
1431 "-net socket[,vlan=n][,name=str][,fd=h][,udp=host:port][,localaddr=host:port]\n"
1432 " connect the vlan 'n' to another VLAN using an UDP tunnel\n"
1434 "-net vde[,vlan=n][,name=str][,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1435 " connect the vlan 'n' to port 'n' of a vde switch running\n"
1436 " on host and listening for incoming connections on 'socketpath'.\n"
1437 " Use group 'groupname' and mode 'octalmode' to change default\n"
1438 " ownership and permissions for communication port.\n"
1440 #ifdef CONFIG_NETMAP
1441 "-net netmap,ifname=name[,devname=nmname]\n"
1442 " attach to the existing netmap-enabled network interface 'name', or to a\n"
1443 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n"
1444 " netmap device, defaults to '/dev/netmap')\n"
1446 "-net dump[,vlan=n][,file=f][,len=n]\n"
1447 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n"
1448 "-net none use it alone to have zero network devices. If no -net option\n"
1449 " is provided, the default is '-net nic -net user'\n", QEMU_ARCH_ALL)
1450 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1460 #ifdef CONFIG_NETMAP
1465 "hubport],id=str[,option][,option][,...]\n", QEMU_ARCH_ALL)
1467 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1469 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1470 = 0 is the default). The NIC is an e1000 by default on the PC
1471 target. Optionally, the MAC address can be changed to @var{mac}, the
1472 device address set to @var{addr} (PCI cards only),
1473 and a @var{name} can be assigned for use in monitor commands.
1474 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1475 that the card should have; this option currently only affects virtio cards; set
1476 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1477 NIC is created. QEMU can emulate several different models of network card.
1478 Valid values for @var{type} are
1479 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1480 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1481 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1482 Not all devices are supported on all targets. Use @code{-net nic,model=help}
1483 for a list of available devices for your target.
1485 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
1487 @item -net user[,@var{option}][,@var{option}][,...]
1488 Use the user mode network stack which requires no administrator
1489 privilege to run. Valid options are:
1493 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1496 @item name=@var{name}
1497 Assign symbolic name for use in monitor commands.
1499 @item net=@var{addr}[/@var{mask}]
1500 Set IP network address the guest will see. Optionally specify the netmask,
1501 either in the form a.b.c.d or as number of valid top-most bits. Default is
1504 @item host=@var{addr}
1505 Specify the guest-visible address of the host. Default is the 2nd IP in the
1506 guest network, i.e. x.x.x.2.
1508 @item restrict=on|off
1509 If this option is enabled, the guest will be isolated, i.e. it will not be
1510 able to contact the host and no guest IP packets will be routed over the host
1511 to the outside. This option does not affect any explicitly set forwarding rules.
1513 @item hostname=@var{name}
1514 Specifies the client hostname reported by the built-in DHCP server.
1516 @item dhcpstart=@var{addr}
1517 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1518 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1520 @item dns=@var{addr}
1521 Specify the guest-visible address of the virtual nameserver. The address must
1522 be different from the host address. Default is the 3rd IP in the guest network,
1525 @item dnssearch=@var{domain}
1526 Provides an entry for the domain-search list sent by the built-in
1527 DHCP server. More than one domain suffix can be transmitted by specifying
1528 this option multiple times. If supported, this will cause the guest to
1529 automatically try to append the given domain suffix(es) in case a domain name
1530 can not be resolved.
1534 qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
1537 @item tftp=@var{dir}
1538 When using the user mode network stack, activate a built-in TFTP
1539 server. The files in @var{dir} will be exposed as the root of a TFTP server.
1540 The TFTP client on the guest must be configured in binary mode (use the command
1541 @code{bin} of the Unix TFTP client).
1543 @item bootfile=@var{file}
1544 When using the user mode network stack, broadcast @var{file} as the BOOTP
1545 filename. In conjunction with @option{tftp}, this can be used to network boot
1546 a guest from a local directory.
1548 Example (using pxelinux):
1550 qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1553 @item smb=@var{dir}[,smbserver=@var{addr}]
1554 When using the user mode network stack, activate a built-in SMB
1555 server so that Windows OSes can access to the host files in @file{@var{dir}}
1556 transparently. The IP address of the SMB server can be set to @var{addr}. By
1557 default the 4th IP in the guest network is used, i.e. x.x.x.4.
1559 In the guest Windows OS, the line:
1563 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1564 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1566 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
1568 Note that a SAMBA server must be installed on the host OS.
1569 QEMU was tested successfully with smbd versions from Red Hat 9,
1570 Fedora Core 3 and OpenSUSE 11.x.
1572 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1573 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1574 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1575 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1576 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1577 be bound to a specific host interface. If no connection type is set, TCP is
1578 used. This option can be given multiple times.
1580 For example, to redirect host X11 connection from screen 1 to guest
1581 screen 0, use the following:
1585 qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1586 # this host xterm should open in the guest X11 server
1590 To redirect telnet connections from host port 5555 to telnet port on
1591 the guest, use the following:
1595 qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
1596 telnet localhost 5555
1599 Then when you use on the host @code{telnet localhost 5555}, you
1600 connect to the guest telnet server.
1602 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1603 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
1604 Forward guest TCP connections to the IP address @var{server} on port @var{port}
1605 to the character device @var{dev} or to a program executed by @var{cmd:command}
1606 which gets spawned for each connection. This option can be given multiple times.
1608 You can either use a chardev directly and have that one used throughout QEMU's
1609 lifetime, like in the following example:
1612 # open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
1613 # the guest accesses it
1614 qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...]
1617 Or you can execute a command on every TCP connection established by the guest,
1618 so that QEMU behaves similar to an inetd process for that virtual server:
1621 # call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
1622 # and connect the TCP stream to its stdin/stdout
1623 qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
1628 Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
1629 processed and applied to -net user. Mixing them with the new configuration
1630 syntax gives undefined results. Their use for new applications is discouraged
1631 as they will be removed from future versions.
1633 @item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1634 @item -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1635 Connect the host TAP network interface @var{name} to VLAN @var{n}.
1637 Use the network script @var{file} to configure it and the network script
1638 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
1639 automatically provides one. The default network configure script is
1640 @file{/etc/qemu-ifup} and the default network deconfigure script is
1641 @file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
1642 to disable script execution.
1644 If running QEMU as an unprivileged user, use the network helper
1645 @var{helper} to configure the TAP interface. The default network
1646 helper executable is @file{/path/to/qemu-bridge-helper}.
1648 @option{fd}=@var{h} can be used to specify the handle of an already
1649 opened host TAP interface.
1654 #launch a QEMU instance with the default network script
1655 qemu-system-i386 linux.img -net nic -net tap
1659 #launch a QEMU instance with two NICs, each one connected
1661 qemu-system-i386 linux.img \
1662 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
1663 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
1667 #launch a QEMU instance with the default network helper to
1668 #connect a TAP device to bridge br0
1669 qemu-system-i386 linux.img \
1670 -net nic -net tap,"helper=/path/to/qemu-bridge-helper"
1673 @item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
1674 @item -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
1675 Connect a host TAP network interface to a host bridge device.
1677 Use the network helper @var{helper} to configure the TAP interface and
1678 attach it to the bridge. The default network helper executable is
1679 @file{/path/to/qemu-bridge-helper} and the default bridge
1680 device is @file{br0}.
1685 #launch a QEMU instance with the default network helper to
1686 #connect a TAP device to bridge br0
1687 qemu-system-i386 linux.img -net bridge -net nic,model=virtio
1691 #launch a QEMU instance with the default network helper to
1692 #connect a TAP device to bridge qemubr0
1693 qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
1696 @item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1697 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1699 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
1700 machine using a TCP socket connection. If @option{listen} is
1701 specified, QEMU waits for incoming connections on @var{port}
1702 (@var{host} is optional). @option{connect} is used to connect to
1703 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
1704 specifies an already opened TCP socket.
1708 # launch a first QEMU instance
1709 qemu-system-i386 linux.img \
1710 -net nic,macaddr=52:54:00:12:34:56 \
1711 -net socket,listen=:1234
1712 # connect the VLAN 0 of this instance to the VLAN 0
1713 # of the first instance
1714 qemu-system-i386 linux.img \
1715 -net nic,macaddr=52:54:00:12:34:57 \
1716 -net socket,connect=127.0.0.1:1234
1719 @item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1720 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1722 Create a VLAN @var{n} shared with another QEMU virtual
1723 machines using a UDP multicast socket, effectively making a bus for
1724 every QEMU with same multicast address @var{maddr} and @var{port}.
1728 Several QEMU can be running on different hosts and share same bus (assuming
1729 correct multicast setup for these hosts).
1731 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
1732 @url{http://user-mode-linux.sf.net}.
1734 Use @option{fd=h} to specify an already opened UDP multicast socket.
1739 # launch one QEMU instance
1740 qemu-system-i386 linux.img \
1741 -net nic,macaddr=52:54:00:12:34:56 \
1742 -net socket,mcast=230.0.0.1:1234
1743 # launch another QEMU instance on same "bus"
1744 qemu-system-i386 linux.img \
1745 -net nic,macaddr=52:54:00:12:34:57 \
1746 -net socket,mcast=230.0.0.1:1234
1747 # launch yet another QEMU instance on same "bus"
1748 qemu-system-i386 linux.img \
1749 -net nic,macaddr=52:54:00:12:34:58 \
1750 -net socket,mcast=230.0.0.1:1234
1753 Example (User Mode Linux compat.):
1755 # launch QEMU instance (note mcast address selected
1757 qemu-system-i386 linux.img \
1758 -net nic,macaddr=52:54:00:12:34:56 \
1759 -net socket,mcast=239.192.168.1:1102
1761 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
1764 Example (send packets from host's 1.2.3.4):
1766 qemu-system-i386 linux.img \
1767 -net nic,macaddr=52:54:00:12:34:56 \
1768 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
1771 @item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1772 @item -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1773 Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
1774 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
1775 and MODE @var{octalmode} to change default ownership and permissions for
1776 communication port. This option is only available if QEMU has been compiled
1777 with vde support enabled.
1782 vde_switch -F -sock /tmp/myswitch
1783 # launch QEMU instance
1784 qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch
1787 @item -netdev hubport,id=@var{id},hubid=@var{hubid}
1789 Create a hub port on QEMU "vlan" @var{hubid}.
1791 The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single
1792 netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the
1793 required hub automatically.
1795 @item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off]
1797 Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should
1798 be a unix domain socket backed one. The vhost-user uses a specifically defined
1799 protocol to pass vhost ioctl replacement messages to an application on the other
1800 end of the socket. On non-MSIX guests, the feature can be forced with
1805 qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \
1806 -numa node,memdev=mem \
1807 -chardev socket,path=/path/to/socket \
1808 -netdev type=vhost-user,id=net0,chardev=chr0 \
1809 -device virtio-net-pci,netdev=net0
1812 @item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
1813 Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
1814 At most @var{len} bytes (64k by default) per packet are stored. The file format is
1815 libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
1818 Indicate that no network devices should be configured. It is used to
1819 override the default configuration (@option{-net nic -net user}) which
1820 is activated if no @option{-net} options are provided.
1828 DEFHEADING(Character device options:)
1831 The general form of a character device option is:
1835 DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
1836 "-chardev null,id=id[,mux=on|off]\n"
1837 "-chardev socket,id=id[,host=host],port=host[,to=to][,ipv4][,ipv6][,nodelay]\n"
1838 " [,server][,nowait][,telnet][,mux=on|off] (tcp)\n"
1839 "-chardev socket,id=id,path=path[,server][,nowait][,telnet],[mux=on|off] (unix)\n"
1840 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
1841 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
1842 "-chardev msmouse,id=id[,mux=on|off]\n"
1843 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
1845 "-chardev ringbuf,id=id[,size=size]\n"
1846 "-chardev file,id=id,path=path[,mux=on|off]\n"
1847 "-chardev pipe,id=id,path=path[,mux=on|off]\n"
1849 "-chardev console,id=id[,mux=on|off]\n"
1850 "-chardev serial,id=id,path=path[,mux=on|off]\n"
1852 "-chardev pty,id=id[,mux=on|off]\n"
1853 "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n"
1855 #ifdef CONFIG_BRLAPI
1856 "-chardev braille,id=id[,mux=on|off]\n"
1858 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
1859 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
1860 "-chardev serial,id=id,path=path[,mux=on|off]\n"
1861 "-chardev tty,id=id,path=path[,mux=on|off]\n"
1863 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
1864 "-chardev parallel,id=id,path=path[,mux=on|off]\n"
1865 "-chardev parport,id=id,path=path[,mux=on|off]\n"
1867 #if defined(CONFIG_SPICE)
1868 "-chardev spicevmc,id=id,name=name[,debug=debug]\n"
1869 "-chardev spiceport,id=id,name=name[,debug=debug]\n"
1875 @item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
1896 The specific backend will determine the applicable options.
1898 All devices must have an id, which can be any string up to 127 characters long.
1899 It is used to uniquely identify this device in other command line directives.
1901 A character device may be used in multiplexing mode by multiple front-ends.
1902 The key sequence of @key{Control-a} and @key{c} will rotate the input focus
1903 between attached front-ends. Specify @option{mux=on} to enable this mode.
1905 Options to each backend are described below.
1907 @item -chardev null ,id=@var{id}
1908 A void device. This device will not emit any data, and will drop any data it
1909 receives. The null backend does not take any options.
1911 @item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet]
1913 Create a two-way stream socket, which can be either a TCP or a unix socket. A
1914 unix socket will be created if @option{path} is specified. Behaviour is
1915 undefined if TCP options are specified for a unix socket.
1917 @option{server} specifies that the socket shall be a listening socket.
1919 @option{nowait} specifies that QEMU should not block waiting for a client to
1920 connect to a listening socket.
1922 @option{telnet} specifies that traffic on the socket should interpret telnet
1925 TCP and unix socket options are given below:
1929 @item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
1931 @option{host} for a listening socket specifies the local address to be bound.
1932 For a connecting socket species the remote host to connect to. @option{host} is
1933 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
1935 @option{port} for a listening socket specifies the local port to be bound. For a
1936 connecting socket specifies the port on the remote host to connect to.
1937 @option{port} can be given as either a port number or a service name.
1938 @option{port} is required.
1940 @option{to} is only relevant to listening sockets. If it is specified, and
1941 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
1942 to and including @option{to} until it succeeds. @option{to} must be specified
1945 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1946 If neither is specified the socket may use either protocol.
1948 @option{nodelay} disables the Nagle algorithm.
1950 @item unix options: path=@var{path}
1952 @option{path} specifies the local path of the unix socket. @option{path} is
1957 @item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
1959 Sends all traffic from the guest to a remote host over UDP.
1961 @option{host} specifies the remote host to connect to. If not specified it
1962 defaults to @code{localhost}.
1964 @option{port} specifies the port on the remote host to connect to. @option{port}
1967 @option{localaddr} specifies the local address to bind to. If not specified it
1968 defaults to @code{0.0.0.0}.
1970 @option{localport} specifies the local port to bind to. If not specified any
1971 available local port will be used.
1973 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1974 If neither is specified the device may use either protocol.
1976 @item -chardev msmouse ,id=@var{id}
1978 Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
1981 @item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
1983 Connect to a QEMU text console. @option{vc} may optionally be given a specific
1986 @option{width} and @option{height} specify the width and height respectively of
1987 the console, in pixels.
1989 @option{cols} and @option{rows} specify that the console be sized to fit a text
1990 console with the given dimensions.
1992 @item -chardev ringbuf ,id=@var{id} [,size=@var{size}]
1994 Create a ring buffer with fixed size @option{size}.
1995 @var{size} must be a power of two, and defaults to @code{64K}).
1997 @item -chardev file ,id=@var{id} ,path=@var{path}
1999 Log all traffic received from the guest to a file.
2001 @option{path} specifies the path of the file to be opened. This file will be
2002 created if it does not already exist, and overwritten if it does. @option{path}
2005 @item -chardev pipe ,id=@var{id} ,path=@var{path}
2007 Create a two-way connection to the guest. The behaviour differs slightly between
2008 Windows hosts and other hosts:
2010 On Windows, a single duplex pipe will be created at
2011 @file{\\.pipe\@option{path}}.
2013 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
2014 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
2015 received by the guest. Data written by the guest can be read from
2016 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
2019 @option{path} forms part of the pipe path as described above. @option{path} is
2022 @item -chardev console ,id=@var{id}
2024 Send traffic from the guest to QEMU's standard output. @option{console} does not
2027 @option{console} is only available on Windows hosts.
2029 @item -chardev serial ,id=@var{id} ,path=@option{path}
2031 Send traffic from the guest to a serial device on the host.
2033 On Unix hosts serial will actually accept any tty device,
2034 not only serial lines.
2036 @option{path} specifies the name of the serial device to open.
2038 @item -chardev pty ,id=@var{id}
2040 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2041 not take any options.
2043 @option{pty} is not available on Windows hosts.
2045 @item -chardev stdio ,id=@var{id} [,signal=on|off]
2046 Connect to standard input and standard output of the QEMU process.
2048 @option{signal} controls if signals are enabled on the terminal, that includes
2049 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2050 default, use @option{signal=off} to disable it.
2052 @option{stdio} is not available on Windows hosts.
2054 @item -chardev braille ,id=@var{id}
2056 Connect to a local BrlAPI server. @option{braille} does not take any options.
2058 @item -chardev tty ,id=@var{id} ,path=@var{path}
2060 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2061 DragonFlyBSD hosts. It is an alias for @option{serial}.
2063 @option{path} specifies the path to the tty. @option{path} is required.
2065 @item -chardev parallel ,id=@var{id} ,path=@var{path}
2066 @item -chardev parport ,id=@var{id} ,path=@var{path}
2068 @option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2070 Connect to a local parallel port.
2072 @option{path} specifies the path to the parallel port device. @option{path} is
2075 @item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2077 @option{spicevmc} is only available when spice support is built in.
2079 @option{debug} debug level for spicevmc
2081 @option{name} name of spice channel to connect to
2083 Connect to a spice virtual machine channel, such as vdiport.
2085 @item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2087 @option{spiceport} is only available when spice support is built in.
2089 @option{debug} debug level for spicevmc
2091 @option{name} name of spice port to connect to
2093 Connect to a spice port, allowing a Spice client to handle the traffic
2094 identified by a name (preferably a fqdn).
2102 DEFHEADING(Device URL Syntax:)
2105 In addition to using normal file images for the emulated storage devices,
2106 QEMU can also use networked resources such as iSCSI devices. These are
2107 specified using a special URL syntax.
2111 iSCSI support allows QEMU to access iSCSI resources directly and use as
2112 images for the guest storage. Both disk and cdrom images are supported.
2114 Syntax for specifying iSCSI LUNs is
2115 ``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
2117 By default qemu will use the iSCSI initiator-name
2118 'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command
2119 line or a configuration file.
2122 Example (without authentication):
2124 qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
2125 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
2126 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2129 Example (CHAP username/password via URL):
2131 qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
2134 Example (CHAP username/password via environment variables):
2136 LIBISCSI_CHAP_USERNAME="user" \
2137 LIBISCSI_CHAP_PASSWORD="password" \
2138 qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2141 iSCSI support is an optional feature of QEMU and only available when
2142 compiled and linked against libiscsi.
2144 DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
2145 "-iscsi [user=user][,password=password]\n"
2146 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
2147 " [,initiator-name=initiator-iqn][,id=target-iqn]\n"
2148 " iSCSI session parameters\n", QEMU_ARCH_ALL)
2151 iSCSI parameters such as username and password can also be specified via
2152 a configuration file. See qemu-doc for more information and examples.
2155 QEMU supports NBD (Network Block Devices) both using TCP protocol as well
2156 as Unix Domain Sockets.
2158 Syntax for specifying a NBD device using TCP
2159 ``nbd:<server-ip>:<port>[:exportname=<export>]''
2161 Syntax for specifying a NBD device using Unix Domain Sockets
2162 ``nbd:unix:<domain-socket>[:exportname=<export>]''
2167 qemu-system-i386 --drive file=nbd:192.0.2.1:30000
2170 Example for Unix Domain Sockets
2172 qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket
2176 QEMU supports SSH (Secure Shell) access to remote disks.
2180 qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img
2181 qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img
2184 Currently authentication must be done using ssh-agent. Other
2185 authentication methods may be supported in future.
2188 Sheepdog is a distributed storage system for QEMU.
2189 QEMU supports using either local sheepdog devices or remote networked
2192 Syntax for specifying a sheepdog device
2194 sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag]
2199 qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine
2202 See also @url{http://http://www.osrg.net/sheepdog/}.
2205 GlusterFS is an user space distributed file system.
2206 QEMU supports the use of GlusterFS volumes for hosting VM disk images using
2207 TCP, Unix Domain Sockets and RDMA transport protocols.
2209 Syntax for specifying a VM disk image on GlusterFS volume is
2211 gluster[+transport]://[server[:port]]/volname/image[?socket=...]
2217 qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img
2220 See also @url{http://www.gluster.org}.
2222 @item HTTP/HTTPS/FTP/FTPS/TFTP
2223 QEMU supports read-only access to files accessed over http(s), ftp(s) and tftp.
2225 Syntax using a single filename:
2227 <protocol>://[<username>[:<password>]@@]<host>/<path>
2233 'http', 'https', 'ftp', 'ftps', or 'tftp'.
2236 Optional username for authentication to the remote server.
2239 Optional password for authentication to the remote server.
2242 Address of the remote server.
2245 Path on the remote server, including any query string.
2248 The following options are also supported:
2251 The full URL when passing options to the driver explicitly.
2254 The amount of data to read ahead with each range request to the remote server.
2255 This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it
2256 does not have a suffix, it will be assumed to be in bytes. The value must be a
2257 multiple of 512 bytes. It defaults to 256k.
2260 Whether to verify the remote server's certificate when connecting over SSL. It
2261 can have the value 'on' or 'off'. It defaults to 'on'.
2264 Note that when passing options to qemu explicitly, @option{driver} is the value
2267 Example: boot from a remote Fedora 20 live ISO image
2269 qemu-system-x86_64 --drive media=cdrom,file=http://dl.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
2271 qemu-system-x86_64 --drive media=cdrom,file.driver=http,file.url=http://dl.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
2274 Example: boot from a remote Fedora 20 cloud image using a local overlay for
2275 writes, copy-on-read, and a readahead of 64k
2277 qemu-img create -f qcow2 -o backing_file='json:@{"file.driver":"http",, "file.url":"https://dl.fedoraproject.org/pub/fedora/linux/releases/20/Images/x86_64/Fedora-x86_64-20-20131211.1-sda.qcow2",, "file.readahead":"64k"@}' /tmp/Fedora-x86_64-20-20131211.1-sda.qcow2
2279 qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on
2282 Example: boot from an image stored on a VMware vSphere server with a self-signed
2283 certificate using a local overlay for writes and a readahead of 64k
2285 qemu-img create -f qcow2 -o backing_file='json:@{"file.driver":"https",, "file.url":"https://user:password@@vsphere.example.com/folder/test/test-flat.vmdk?dcPath=Datacenter&dsName=datastore1",, "file.sslverify":"off",, "file.readahead":"64k"@}' /tmp/test.qcow2
2287 qemu-system-x86_64 -drive file=/tmp/test.qcow2
2295 DEFHEADING(Bluetooth(R) options:)
2300 DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
2301 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \
2302 "-bt hci,host[:id]\n" \
2303 " use host's HCI with the given name\n" \
2304 "-bt hci[,vlan=n]\n" \
2305 " emulate a standard HCI in virtual scatternet 'n'\n" \
2306 "-bt vhci[,vlan=n]\n" \
2307 " add host computer to virtual scatternet 'n' using VHCI\n" \
2308 "-bt device:dev[,vlan=n]\n" \
2309 " emulate a bluetooth device 'dev' in scatternet 'n'\n",
2314 Defines the function of the corresponding Bluetooth HCI. -bt options
2315 are matched with the HCIs present in the chosen machine type. For
2316 example when emulating a machine with only one HCI built into it, only
2317 the first @code{-bt hci[...]} option is valid and defines the HCI's
2318 logic. The Transport Layer is decided by the machine type. Currently
2319 the machines @code{n800} and @code{n810} have one HCI and all other
2323 The following three types are recognized:
2327 (default) The corresponding Bluetooth HCI assumes no internal logic
2328 and will not respond to any HCI commands or emit events.
2330 @item -bt hci,host[:@var{id}]
2331 (@code{bluez} only) The corresponding HCI passes commands / events
2332 to / from the physical HCI identified by the name @var{id} (default:
2333 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
2334 capable systems like Linux.
2336 @item -bt hci[,vlan=@var{n}]
2337 Add a virtual, standard HCI that will participate in the Bluetooth
2338 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
2339 VLANs, devices inside a bluetooth network @var{n} can only communicate
2340 with other devices in the same network (scatternet).
2343 @item -bt vhci[,vlan=@var{n}]
2344 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2345 to the host bluetooth stack instead of to the emulated target. This
2346 allows the host and target machines to participate in a common scatternet
2347 and communicate. Requires the Linux @code{vhci} driver installed. Can
2348 be used as following:
2351 qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2354 @item -bt device:@var{dev}[,vlan=@var{n}]
2355 Emulate a bluetooth device @var{dev} and place it in network @var{n}
2356 (default @code{0}). QEMU can only emulate one type of bluetooth devices
2361 Virtual wireless keyboard implementing the HIDP bluetooth profile.
2371 DEFHEADING(TPM device options:)
2373 DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
2374 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
2375 " use path to provide path to a character device; default is /dev/tpm0\n"
2376 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
2377 " not provided it will be searched for in /sys/class/misc/tpm?/device\n",
2381 The general form of a TPM device option is:
2384 @item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
2386 Backend type must be:
2387 @option{passthrough}.
2389 The specific backend type will determine the applicable options.
2390 The @code{-tpmdev} option creates the TPM backend and requires a
2391 @code{-device} option that specifies the TPM frontend interface model.
2393 Options to each backend are described below.
2395 Use 'help' to print all available TPM backend types.
2400 @item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path}
2402 (Linux-host only) Enable access to the host's TPM using the passthrough
2405 @option{path} specifies the path to the host's TPM device, i.e., on
2406 a Linux host this would be @code{/dev/tpm0}.
2407 @option{path} is optional and by default @code{/dev/tpm0} is used.
2409 @option{cancel-path} specifies the path to the host TPM device's sysfs
2410 entry allowing for cancellation of an ongoing TPM command.
2411 @option{cancel-path} is optional and by default QEMU will search for the
2414 Some notes about using the host's TPM with the passthrough driver:
2416 The TPM device accessed by the passthrough driver must not be
2417 used by any other application on the host.
2419 Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
2420 the VM's firmware (BIOS/UEFI) will not be able to initialize the
2421 TPM again and may therefore not show a TPM-specific menu that would
2422 otherwise allow the user to configure the TPM, e.g., allow the user to
2423 enable/disable or activate/deactivate the TPM.
2424 Further, if TPM ownership is released from within a VM then the host's TPM
2425 will get disabled and deactivated. To enable and activate the
2426 TPM again afterwards, the host has to be rebooted and the user is
2427 required to enter the firmware's menu to enable and activate the TPM.
2428 If the TPM is left disabled and/or deactivated most TPM commands will fail.
2430 To create a passthrough TPM use the following two options:
2432 -tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
2434 Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
2435 @code{tpmdev=tpm0} in the device option.
2445 DEFHEADING(Linux/Multiboot boot specific:)
2448 When using these options, you can use a given Linux or Multiboot
2449 kernel without installing it in the disk image. It can be useful
2450 for easier testing of various kernels.
2455 DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
2456 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL)
2458 @item -kernel @var{bzImage}
2460 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2461 or in multiboot format.
2464 DEF("append", HAS_ARG, QEMU_OPTION_append, \
2465 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL)
2467 @item -append @var{cmdline}
2469 Use @var{cmdline} as kernel command line
2472 DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
2473 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL)
2475 @item -initrd @var{file}
2477 Use @var{file} as initial ram disk.
2479 @item -initrd "@var{file1} arg=foo,@var{file2}"
2481 This syntax is only available with multiboot.
2483 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
2487 DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
2488 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL)
2490 @item -dtb @var{file}
2492 Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
2501 DEFHEADING(Debug/Expert options:)
2506 DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
2507 "-serial dev redirect the serial port to char device 'dev'\n",
2510 @item -serial @var{dev}
2512 Redirect the virtual serial port to host character device
2513 @var{dev}. The default device is @code{vc} in graphical mode and
2514 @code{stdio} in non graphical mode.
2516 This option can be used several times to simulate up to 4 serial
2519 Use @code{-serial none} to disable all serial ports.
2521 Available character devices are:
2523 @item vc[:@var{W}x@var{H}]
2524 Virtual console. Optionally, a width and height can be given in pixel with
2528 It is also possible to specify width or height in characters:
2533 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
2535 No device is allocated.
2538 @item chardev:@var{id}
2539 Use a named character device defined with the @code{-chardev} option.
2541 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
2542 parameters are set according to the emulated ones.
2543 @item /dev/parport@var{N}
2544 [Linux only, parallel port only] Use host parallel port
2545 @var{N}. Currently SPP and EPP parallel port features can be used.
2546 @item file:@var{filename}
2547 Write output to @var{filename}. No character can be read.
2549 [Unix only] standard input/output
2550 @item pipe:@var{filename}
2551 name pipe @var{filename}
2553 [Windows only] Use host serial port @var{n}
2554 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
2555 This implements UDP Net Console.
2556 When @var{remote_host} or @var{src_ip} are not specified
2557 they default to @code{0.0.0.0}.
2558 When not using a specified @var{src_port} a random port is automatically chosen.
2560 If you just want a simple readonly console you can use @code{netcat} or
2561 @code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
2562 @code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
2563 will appear in the netconsole session.
2565 If you plan to send characters back via netconsole or you want to stop
2566 and start QEMU a lot of times, you should have QEMU use the same
2567 source port each time by using something like @code{-serial
2568 udp::4555@@:4556} to QEMU. Another approach is to use a patched
2569 version of netcat which can listen to a TCP port and send and receive
2570 characters via udp. If you have a patched version of netcat which
2571 activates telnet remote echo and single char transfer, then you can
2572 use the following options to step up a netcat redirector to allow
2573 telnet on port 5555 to access the QEMU port.
2576 -serial udp::4555@@:4556
2577 @item netcat options:
2578 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
2579 @item telnet options:
2583 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay]
2584 The TCP Net Console has two modes of operation. It can send the serial
2585 I/O to a location or wait for a connection from a location. By default
2586 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
2587 the @var{server} option QEMU will wait for a client socket application
2588 to connect to the port before continuing, unless the @code{nowait}
2589 option was specified. The @code{nodelay} option disables the Nagle buffering
2590 algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only
2591 one TCP connection at a time is accepted. You can use @code{telnet} to
2592 connect to the corresponding character device.
2594 @item Example to send tcp console to 192.168.0.2 port 4444
2595 -serial tcp:192.168.0.2:4444
2596 @item Example to listen and wait on port 4444 for connection
2597 -serial tcp::4444,server
2598 @item Example to not wait and listen on ip 192.168.0.100 port 4444
2599 -serial tcp:192.168.0.100:4444,server,nowait
2602 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
2603 The telnet protocol is used instead of raw tcp sockets. The options
2604 work the same as if you had specified @code{-serial tcp}. The
2605 difference is that the port acts like a telnet server or client using
2606 telnet option negotiation. This will also allow you to send the
2607 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
2608 sequence. Typically in unix telnet you do it with Control-] and then
2609 type "send break" followed by pressing the enter key.
2611 @item unix:@var{path}[,server][,nowait]
2612 A unix domain socket is used instead of a tcp socket. The option works the
2613 same as if you had specified @code{-serial tcp} except the unix domain socket
2614 @var{path} is used for connections.
2616 @item mon:@var{dev_string}
2617 This is a special option to allow the monitor to be multiplexed onto
2618 another serial port. The monitor is accessed with key sequence of
2619 @key{Control-a} and then pressing @key{c}.
2620 @var{dev_string} should be any one of the serial devices specified
2621 above. An example to multiplex the monitor onto a telnet server
2622 listening on port 4444 would be:
2624 @item -serial mon:telnet::4444,server,nowait
2626 When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
2627 QEMU any more but will be passed to the guest instead.
2630 Braille device. This will use BrlAPI to display the braille output on a real
2634 Three button serial mouse. Configure the guest to use Microsoft protocol.
2638 DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
2639 "-parallel dev redirect the parallel port to char device 'dev'\n",
2642 @item -parallel @var{dev}
2644 Redirect the virtual parallel port to host device @var{dev} (same
2645 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
2646 be used to use hardware devices connected on the corresponding host
2649 This option can be used several times to simulate up to 3 parallel
2652 Use @code{-parallel none} to disable all parallel ports.
2655 DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
2656 "-monitor dev redirect the monitor to char device 'dev'\n",
2659 @item -monitor @var{dev}
2661 Redirect the monitor to host device @var{dev} (same devices as the
2663 The default device is @code{vc} in graphical mode and @code{stdio} in
2665 Use @code{-monitor none} to disable the default monitor.
2667 DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
2668 "-qmp dev like -monitor but opens in 'control' mode\n",
2671 @item -qmp @var{dev}
2673 Like -monitor but opens in 'control' mode.
2676 DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
2677 "-mon [chardev=]name[,mode=readline|control][,default]\n", QEMU_ARCH_ALL)
2679 @item -mon [chardev=]name[,mode=readline|control][,default]
2681 Setup monitor on chardev @var{name}.
2684 DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
2685 "-debugcon dev redirect the debug console to char device 'dev'\n",
2688 @item -debugcon @var{dev}
2690 Redirect the debug console to host device @var{dev} (same devices as the
2691 serial port). The debug console is an I/O port which is typically port
2692 0xe9; writing to that I/O port sends output to this device.
2693 The default device is @code{vc} in graphical mode and @code{stdio} in
2697 DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
2698 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL)
2700 @item -pidfile @var{file}
2702 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
2706 DEF("singlestep", 0, QEMU_OPTION_singlestep, \
2707 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL)
2711 Run the emulation in single step mode.
2714 DEF("S", 0, QEMU_OPTION_S, \
2715 "-S freeze CPU at startup (use 'c' to start execution)\n",
2720 Do not start CPU at startup (you must type 'c' in the monitor).
2723 DEF("realtime", HAS_ARG, QEMU_OPTION_realtime,
2724 "-realtime [mlock=on|off]\n"
2725 " run qemu with realtime features\n"
2726 " mlock=on|off controls mlock support (default: on)\n",
2729 @item -realtime mlock=on|off
2731 Run qemu with realtime features.
2732 mlocking qemu and guest memory can be enabled via @option{mlock=on}
2733 (enabled by default).
2736 DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
2737 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL)
2739 @item -gdb @var{dev}
2741 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
2742 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
2743 stdio are reasonable use case. The latter is allowing to start QEMU from
2744 within gdb and establish the connection via a pipe:
2746 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
2750 DEF("s", 0, QEMU_OPTION_s, \
2751 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
2756 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
2757 (@pxref{gdb_usage}).
2760 DEF("d", HAS_ARG, QEMU_OPTION_d, \
2761 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n",
2764 @item -d @var{item1}[,...]
2766 Enable logging of specified items. Use '-d help' for a list of log items.
2769 DEF("D", HAS_ARG, QEMU_OPTION_D, \
2770 "-D logfile output log to logfile (default stderr)\n",
2773 @item -D @var{logfile}
2775 Output log in @var{logfile} instead of to stderr
2778 DEF("L", HAS_ARG, QEMU_OPTION_L, \
2779 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
2784 Set the directory for the BIOS, VGA BIOS and keymaps.
2787 DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
2788 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL)
2790 @item -bios @var{file}
2792 Set the filename for the BIOS.
2795 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
2796 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL)
2800 Enable KVM full virtualization support. This option is only available
2801 if KVM support is enabled when compiling.
2804 DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
2805 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL)
2806 DEF("xen-create", 0, QEMU_OPTION_xen_create,
2807 "-xen-create create domain using xen hypercalls, bypassing xend\n"
2808 " warning: should not be used when xend is in use\n",
2810 DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
2811 "-xen-attach attach to existing xen domain\n"
2812 " xend will use this when starting QEMU\n",
2815 @item -xen-domid @var{id}
2817 Specify xen guest domain @var{id} (XEN only).
2820 Create domain using xen hypercalls, bypassing xend.
2821 Warning: should not be used when xend is in use (XEN only).
2824 Attach to existing xen domain.
2825 xend will use this when starting QEMU (XEN only).
2828 DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
2829 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL)
2833 Exit instead of rebooting.
2836 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
2837 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL)
2840 @findex -no-shutdown
2841 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
2842 This allows for instance switching to monitor to commit changes to the
2846 DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
2847 "-loadvm [tag|id]\n" \
2848 " start right away with a saved state (loadvm in monitor)\n",
2851 @item -loadvm @var{file}
2853 Start right away with a saved state (@code{loadvm} in monitor)
2857 DEF("daemonize", 0, QEMU_OPTION_daemonize, \
2858 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
2863 Daemonize the QEMU process after initialization. QEMU will not detach from
2864 standard IO until it is ready to receive connections on any of its devices.
2865 This option is a useful way for external programs to launch QEMU without having
2866 to cope with initialization race conditions.
2869 DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
2870 "-option-rom rom load a file, rom, into the option ROM space\n",
2873 @item -option-rom @var{file}
2875 Load the contents of @var{file} as an option ROM.
2876 This option is useful to load things like EtherBoot.
2879 DEF("clock", HAS_ARG, QEMU_OPTION_clock, \
2880 "-clock force the use of the given methods for timer alarm.\n" \
2881 " To see what timers are available use '-clock help'\n",
2884 @item -clock @var{method}
2886 Force the use of the given methods for timer alarm. To see what timers
2887 are available use @code{-clock help}.
2890 HXCOMM Options deprecated by -rtc
2891 DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
2892 DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
2894 DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
2895 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
2896 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
2901 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
2903 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
2904 UTC or local time, respectively. @code{localtime} is required for correct date in
2905 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
2906 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
2908 By default the RTC is driven by the host system time. This allows using of the
2909 RTC as accurate reference clock inside the guest, specifically if the host
2910 time is smoothly following an accurate external reference clock, e.g. via NTP.
2911 If you want to isolate the guest time from the host, you can set @option{clock}
2912 to @code{rt} instead. To even prevent it from progressing during suspension,
2913 you can set it to @code{vm}.
2915 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
2916 specifically with Windows' ACPI HAL. This option will try to figure out how
2917 many timer interrupts were not processed by the Windows guest and will
2921 DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
2922 "-icount [N|auto]\n" \
2923 " enable virtual instruction counter with 2^N clock ticks per\n" \
2924 " instruction\n", QEMU_ARCH_ALL)
2926 @item -icount [@var{N}|auto]
2928 Enable virtual instruction counter. The virtual cpu will execute one
2929 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
2930 then the virtual cpu speed will be automatically adjusted to keep virtual
2931 time within a few seconds of real time.
2933 Note that while this option can give deterministic behavior, it does not
2934 provide cycle accurate emulation. Modern CPUs contain superscalar out of
2935 order cores with complex cache hierarchies. The number of instructions
2936 executed often has little or no correlation with actual performance.
2939 DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
2940 "-watchdog i6300esb|ib700\n" \
2941 " enable virtual hardware watchdog [default=none]\n",
2944 @item -watchdog @var{model}
2946 Create a virtual hardware watchdog device. Once enabled (by a guest
2947 action), the watchdog must be periodically polled by an agent inside
2948 the guest or else the guest will be restarted.
2950 The @var{model} is the model of hardware watchdog to emulate. Choices
2951 for model are: @code{ib700} (iBASE 700) which is a very simple ISA
2952 watchdog with a single timer, or @code{i6300esb} (Intel 6300ESB I/O
2953 controller hub) which is a much more featureful PCI-based dual-timer
2954 watchdog. Choose a model for which your guest has drivers.
2956 Use @code{-watchdog help} to list available hardware models. Only one
2957 watchdog can be enabled for a guest.
2960 DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
2961 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
2962 " action when watchdog fires [default=reset]\n",
2965 @item -watchdog-action @var{action}
2966 @findex -watchdog-action
2968 The @var{action} controls what QEMU will do when the watchdog timer
2971 @code{reset} (forcefully reset the guest).
2972 Other possible actions are:
2973 @code{shutdown} (attempt to gracefully shutdown the guest),
2974 @code{poweroff} (forcefully poweroff the guest),
2975 @code{pause} (pause the guest),
2976 @code{debug} (print a debug message and continue), or
2977 @code{none} (do nothing).
2979 Note that the @code{shutdown} action requires that the guest responds
2980 to ACPI signals, which it may not be able to do in the sort of
2981 situations where the watchdog would have expired, and thus
2982 @code{-watchdog-action shutdown} is not recommended for production use.
2987 @item -watchdog i6300esb -watchdog-action pause
2988 @item -watchdog ib700
2992 DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
2993 "-echr chr set terminal escape character instead of ctrl-a\n",
2997 @item -echr @var{numeric_ascii_value}
2999 Change the escape character used for switching to the monitor when using
3000 monitor and serial sharing. The default is @code{0x01} when using the
3001 @code{-nographic} option. @code{0x01} is equal to pressing
3002 @code{Control-a}. You can select a different character from the ascii
3003 control keys where 1 through 26 map to Control-a through Control-z. For
3004 instance you could use the either of the following to change the escape
3005 character to Control-t.
3012 DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
3013 "-virtioconsole c\n" \
3014 " set virtio console\n", QEMU_ARCH_ALL)
3016 @item -virtioconsole @var{c}
3017 @findex -virtioconsole
3020 This option is maintained for backward compatibility.
3022 Please use @code{-device virtconsole} for the new way of invocation.
3025 DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
3026 "-show-cursor show cursor\n", QEMU_ARCH_ALL)
3029 @findex -show-cursor
3033 DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
3034 "-tb-size n set TB size\n", QEMU_ARCH_ALL)
3036 @item -tb-size @var{n}
3041 DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
3042 "-incoming p prepare for incoming migration, listen on port p\n",
3045 @item -incoming @var{port}
3047 Prepare for incoming migration, listen on @var{port}.
3050 DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
3051 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL)
3055 Don't create default devices. Normally, QEMU sets the default devices like serial
3056 port, parallel port, virtual console, monitor device, VGA adapter, floppy and
3057 CD-ROM drive and others. The @code{-nodefaults} option will disable all those
3062 DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
3063 "-chroot dir chroot to dir just before starting the VM\n",
3067 @item -chroot @var{dir}
3069 Immediately before starting guest execution, chroot to the specified
3070 directory. Especially useful in combination with -runas.
3074 DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
3075 "-runas user change to user id user just before starting the VM\n",
3079 @item -runas @var{user}
3081 Immediately before starting guest execution, drop root privileges, switching
3082 to the specified user.
3085 DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
3086 "-prom-env variable=value\n"
3087 " set OpenBIOS nvram variables\n",
3088 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3090 @item -prom-env @var{variable}=@var{value}
3092 Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
3094 DEF("semihosting", 0, QEMU_OPTION_semihosting,
3095 "-semihosting semihosting mode\n",
3096 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32)
3099 @findex -semihosting
3100 Semihosting mode (ARM, M68K, Xtensa only).
3102 DEF("old-param", 0, QEMU_OPTION_old_param,
3103 "-old-param old param mode\n", QEMU_ARCH_ARM)
3106 @findex -old-param (ARM)
3107 Old param mode (ARM only).
3110 DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
3111 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n",
3114 @item -sandbox @var{arg}
3116 Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
3117 disable it. The default is 'off'.
3120 DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
3121 "-readconfig <file>\n", QEMU_ARCH_ALL)
3123 @item -readconfig @var{file}
3125 Read device configuration from @var{file}. This approach is useful when you want to spawn
3126 QEMU process with many command line options but you don't want to exceed the command line
3129 DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
3130 "-writeconfig <file>\n"
3131 " read/write config file\n", QEMU_ARCH_ALL)
3133 @item -writeconfig @var{file}
3134 @findex -writeconfig
3135 Write device configuration to @var{file}. The @var{file} can be either filename to save
3136 command line and device configuration into file or dash @code{-}) character to print the
3137 output to stdout. This can be later used as input file for @code{-readconfig} option.
3139 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig,
3141 " do not load default config files at startup\n",
3145 @findex -nodefconfig
3146 Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
3147 The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
3149 DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
3151 " do not load user-provided config files at startup\n",
3154 @item -no-user-config
3155 @findex -no-user-config
3156 The @code{-no-user-config} option makes QEMU not load any of the user-provided
3157 config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config
3158 files from @var{datadir}.
3160 DEF("trace", HAS_ARG, QEMU_OPTION_trace,
3161 "-trace [events=<file>][,file=<file>]\n"
3162 " specify tracing options\n",
3165 HXCOMM This line is not accurate, as some sub-options are backend-specific but
3166 HXCOMM HX does not support conditional compilation of text.
3167 @item -trace [events=@var{file}][,file=@var{file}]
3170 Specify tracing options.
3173 @item events=@var{file}
3174 Immediately enable events listed in @var{file}.
3175 The file must contain one event name (as listed in the @var{trace-events} file)
3177 This option is only available if QEMU has been compiled with
3178 either @var{simple} or @var{stderr} tracing backend.
3179 @item file=@var{file}
3180 Log output traces to @var{file}.
3182 This option is only available if QEMU has been compiled with
3183 the @var{simple} tracing backend.
3188 DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL)
3189 DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL)
3192 DEF("enable-fips", 0, QEMU_OPTION_enablefips,
3193 "-enable-fips enable FIPS 140-2 compliance\n",
3198 @findex -enable-fips
3199 Enable FIPS 140-2 compliance mode.
3202 HXCOMM Deprecated by -machine accel=tcg property
3203 DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386)
3205 HXCOMM Deprecated by kvm-pit driver properties
3206 DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection,
3209 HXCOMM Deprecated (ignored)
3210 DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386)
3212 HXCOMM Deprecated by -machine kernel_irqchip=on|off property
3213 DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386)
3215 HXCOMM Deprecated (ignored)
3216 DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL)
3218 DEF("object", HAS_ARG, QEMU_OPTION_object,
3219 "-object TYPENAME[,PROP1=VALUE1,...]\n"
3220 " create an new object of type TYPENAME setting properties\n"
3221 " in the order they are specified. Note that the 'id'\n"
3222 " property must be set. These objects are placed in the\n"
3223 " '/objects' path.\n",
3226 @item -object @var{typename}[,@var{prop1}=@var{value1},...]
3228 Create an new object of type @var{typename} setting properties
3229 in the order they are specified. Note that the 'id'
3230 property must be set. These objects are placed in the
3234 DEF("msg", HAS_ARG, QEMU_OPTION_msg,
3235 "-msg timestamp[=on|off]\n"
3236 " change the format of messages\n"
3237 " on|off controls leading timestamps (default:on)\n",
3240 @item -msg timestamp[=on|off]
3242 prepend a timestamp to each log message.(default:on)
3245 HXCOMM This is the last statement. Insert new options before this line!