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 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 @
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 megs set virtual RAM size to megs MB [default="
214 stringify(DEFAULT_RAM_SIZE) "]\n", QEMU_ARCH_ALL)
218 Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally,
219 a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or
220 gigabytes respectively.
223 DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
224 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
226 @item -mem-path @var{path}
228 Allocate guest RAM from a temporarily created file in @var{path}.
232 DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
233 "-mem-prealloc preallocate guest memory (use with -mem-path)\n",
237 @findex -mem-prealloc
238 Preallocate memory when using -mem-path.
242 DEF("k", HAS_ARG, QEMU_OPTION_k,
243 "-k language use keyboard layout (for example 'fr
' for French)\n",
246 @item -k @var{language}
248 Use keyboard layout @var{language} (for example @code{fr} for
249 French). This option is only needed where it is not easy to get raw PC
250 keycodes (e.g. on Macs, with some X11 servers or with a VNC
251 display). You don't normally need to use it on PC
/Linux or PC
/Windows
254 The available layouts are
:
256 ar de
-ch es fo fr
-ca hu ja mk no pt
-br sv
257 da en
-gb et fr fr
-ch is lt nl pl ru th
258 de en
-us fi fr
-be hr it lv nl
-be pt sl tr
261 The
default is @code
{en
-us
}.
265 DEF("audio-help", 0, QEMU_OPTION_audio_help
,
266 "-audio-help print list of audio drivers and their options\n",
271 Will show the audio subsystem help
: list of drivers
, tunable
275 DEF("soundhw", HAS_ARG
, QEMU_OPTION_soundhw
,
276 "-soundhw c1,... enable audio support\n"
277 " and only specified sound cards (comma separated list)\n"
278 " use '-soundhw help' to get the list of supported cards\n"
279 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL
)
281 @item
-soundhw @
var{card1
}[,@
var{card2
},...] or
-soundhw all
283 Enable audio and selected sound hardware
. Use
'help' to print all
284 available sound hardware
.
287 qemu
-system
-i386
-soundhw sb16
,adlib disk
.img
288 qemu
-system
-i386
-soundhw es1370 disk
.img
289 qemu
-system
-i386
-soundhw ac97 disk
.img
290 qemu
-system
-i386
-soundhw hda disk
.img
291 qemu
-system
-i386
-soundhw all disk
.img
292 qemu
-system
-i386
-soundhw help
295 Note that Linux
's i810_audio OSS kernel (for AC97) module might
296 require manually specifying clocking.
299 modprobe i810_audio clocking=48000
303 DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
304 "-balloon none disable balloon device\n"
305 "-balloon virtio[,addr=str]\n"
306 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL)
310 Disable balloon device.
311 @item -balloon virtio[,addr=@var{addr}]
312 Enable virtio balloon device (default), optionally with PCI address
316 DEF("device", HAS_ARG, QEMU_OPTION_device,
317 "-device driver[,prop[=value][,...]]\n"
318 " add device (based on driver)\n"
319 " prop=value,... sets driver properties\n"
320 " use '-device help
' to print all possible drivers\n"
321 " use '-device driver
,help
' to print all possible properties\n",
324 @item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
326 Add device @var{driver}. @var{prop}=@var{value} sets driver
327 properties. Valid properties depend on the driver. To get help on
328 possible drivers and properties, use @code{-device help} and
329 @code{-device @var{driver},help}.
332 DEF("name", HAS_ARG, QEMU_OPTION_name,
333 "-name string1[,process=string2]\n"
334 " set the name of the guest\n"
335 " string1 sets the window title and string2 the process name (on Linux)\n",
338 @item -name @var{name}
340 Sets the @var{name} of the guest.
341 This name will be displayed in the SDL window caption.
342 The @var{name} will also be used for the VNC server.
343 Also optionally set the top visible process name in Linux.
346 DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
347 "-uuid %08x-%04x-%04x-%04x-%012x\n"
348 " specify machine UUID\n", QEMU_ARCH_ALL)
350 @item -uuid @var{uuid}
360 DEFHEADING(Block device options:)
365 DEF("fda", HAS_ARG, QEMU_OPTION_fda,
366 "-fda/-fdb file use 'file
' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
367 DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
369 @item -fda @var{file}
370 @item -fdb @var{file}
373 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can
374 use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}).
377 DEF("hda", HAS_ARG, QEMU_OPTION_hda,
378 "-hda/-hdb file use 'file
' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
379 DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
380 DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
381 "-hdc/-hdd file use 'file
' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
382 DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
384 @item -hda @var{file}
385 @item -hdb @var{file}
386 @item -hdc @var{file}
387 @item -hdd @var{file}
392 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
395 DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
396 "-cdrom file use 'file
' as IDE cdrom image (cdrom is ide1 master)\n",
399 @item -cdrom @var{file}
401 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
402 @option{-cdrom} at the same time). You can use the host CD-ROM by
403 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
406 DEF("drive", HAS_ARG, QEMU_OPTION_drive,
407 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
408 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
409 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
410 " [,serial=s][,addr=A][,id=name][,aio=threads|native]\n"
411 " [,readonly=on|off][,copy-on-read=on|off]\n"
412 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]][[,iops=i]|[[,iops_rd=r][,iops_wr=w]]\n"
413 " use 'file
' as a drive image\n", QEMU_ARCH_ALL)
415 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
418 Define a new drive. Valid options are:
421 @item file=@var{file}
422 This option defines which disk image (@pxref{disk_images}) to use with
423 this drive. If the filename contains comma, you must double it
424 (for instance, "file=my,,file" to use file "my,file").
426 Special files such as iSCSI devices can be specified using protocol
427 specific URLs. See the section for "Device URL Syntax" for more information.
428 @item if=@var{interface}
429 This option defines on which type on interface the drive is connected.
430 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio.
431 @item bus=@var{bus},unit=@var{unit}
432 These options define where is connected the drive by defining the bus number and
434 @item index=@var{index}
435 This option defines where is connected the drive by using an index in the list
436 of available connectors of a given interface type.
437 @item media=@var{media}
438 This option defines the type of the media: disk or cdrom.
439 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
440 These options have the same definition as they have in @option{-hdachs}.
441 @item snapshot=@var{snapshot}
442 @var{snapshot} is "on" or "off" and allows to enable snapshot for given drive (see @option{-snapshot}).
443 @item cache=@var{cache}
444 @var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data.
446 @var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
447 @item discard=@var{discard}
448 @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.
449 @item format=@var{format}
450 Specify which disk @var{format} will be used rather than detecting
451 the format. Can be used to specifiy format=raw to avoid interpreting
452 an untrusted format header.
453 @item serial=@var{serial}
454 This option specifies the serial number to assign to the device.
455 @item addr=@var{addr}
456 Specify the controller's PCI
address (if=virtio only
).
457 @item werror
=@
var{action
},rerror
=@
var{action
}
458 Specify which @
var{action
} to take on write and read errors
. Valid actions are
:
459 "ignore" (ignore the error and
try to
continue), "stop" (pause QEMU
),
460 "report" (report the error to the guest
), "enospc" (pause QEMU only
if the
461 host disk is full
; report the error to the guest otherwise
).
462 The
default setting is @option
{werror
=enospc
} and @option
{rerror
=report
}.
464 Open drive @option
{file
} as read
-only
. Guest write attempts will fail
.
465 @item copy
-on
-read
=@
var{copy
-on
-read
}
466 @
var{copy
-on
-read
} is
"on" or
"off" and enables whether to copy read backing
467 file sectors into the image file
.
470 By
default, the @option
{cache
=writeback
} mode is used
. It will report data
471 writes as completed as soon as the data is present
in the host page cache
.
472 This is safe as long as your guest OS makes sure to correctly flush disk caches
473 where needed
. If your guest OS does not handle volatile disk write caches
474 correctly and your host crashes or loses power
, then the guest may experience
477 For such guests
, you should consider
using @option
{cache
=writethrough
}. This
478 means that the host page cache will be used to read and write data
, but write
479 notification will be sent to the guest only after QEMU has made sure to flush
480 each write to the disk
. Be aware that
this has a major impact on performance
.
482 The host page cache can be avoided entirely with @option
{cache
=none
}. This will
483 attempt to
do disk IO directly to the guest
's memory. QEMU may still perform
484 an internal copy of the data. Note that this is considered a writeback mode and
485 the guest OS must handle the disk write cache correctly in order to avoid data
486 corruption on host crashes.
488 The host page cache can be avoided while only sending write notifications to
489 the guest when the data has been flushed to the disk using
490 @option{cache=directsync}.
492 In case you don't care about data integrity over host failures
, use
493 @option
{cache
=unsafe
}. This option tells QEMU that it
never needs to write any
494 data to the disk but can instead keep things
in cache
. If anything goes wrong
,
495 like your host losing power
, the disk storage getting disconnected accidentally
,
496 etc
. your image will most probably be rendered unusable
. When
using
497 the @option
{-snapshot
} option
, unsafe caching is always used
.
499 Copy
-on
-read avoids accessing the same backing file sectors repeatedly and is
500 useful when the backing file is over a slow network
. By
default copy
-on
-read
503 Instead of @option
{-cdrom
} you can use
:
505 qemu
-system
-i386
-drive file
=file
,index
=2,media
=cdrom
508 Instead of @option
{-hda
}, @option
{-hdb
}, @option
{-hdc
}, @option
{-hdd
}, you can
511 qemu
-system
-i386
-drive file
=file
,index
=0,media
=disk
512 qemu
-system
-i386
-drive file
=file
,index
=1,media
=disk
513 qemu
-system
-i386
-drive file
=file
,index
=2,media
=disk
514 qemu
-system
-i386
-drive file
=file
,index
=3,media
=disk
517 You can open an image
using pre
-opened file descriptors from an fd set
:
520 -add
-fd fd
=3,set
=2,opaque
="rdwr:/path/to/file"
521 -add
-fd fd
=4,set
=2,opaque
="rdonly:/path/to/file"
522 -drive file
=/dev
/fdset
/2,index
=0,media
=disk
525 You can connect a CDROM to the slave of ide0
:
527 qemu
-system
-i386
-drive file
=file
,if=ide
,index
=1,media
=cdrom
530 If you don
't specify the "file=" argument, you define an empty drive:
532 qemu-system-i386 -drive if=ide,index=1,media=cdrom
535 You can connect a SCSI disk with unit ID 6 on the bus #0:
537 qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6
540 Instead of @option{-fda}, @option{-fdb}, you can use:
542 qemu-system-i386 -drive file=file,index=0,if=floppy
543 qemu-system-i386 -drive file=file,index=1,if=floppy
546 By default, @var{interface} is "ide" and @var{index} is automatically
549 qemu-system-i386 -drive file=a -drive file=b"
553 qemu-system-i386 -hda a -hdb b
557 DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
558 "-mtdblock file use 'file
' as on-board Flash memory image\n",
561 @item -mtdblock @var{file}
563 Use @var{file} as on-board Flash memory image.
566 DEF("sd", HAS_ARG, QEMU_OPTION_sd,
567 "-sd file use 'file
' as SecureDigital card image\n", QEMU_ARCH_ALL)
571 Use @var{file} as SecureDigital card image.
574 DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
575 "-pflash file use 'file
' as a parallel flash image\n", QEMU_ARCH_ALL)
577 @item -pflash @var{file}
579 Use @var{file} as a parallel flash image.
582 DEF("snapshot", 0, QEMU_OPTION_snapshot,
583 "-snapshot write to temporary files instead of disk image files\n",
588 Write to temporary files instead of disk image files. In this case,
589 the raw disk image you use is not written back. You can however force
590 the write back by pressing @key{C-a s} (@pxref{disk_images}).
593 DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
594 "-hdachs c,h,s[,t]\n" \
595 " force hard disk 0 physical geometry and the optional BIOS\n" \
596 " translation (t=none or lba) (usually QEMU can guess them)\n",
599 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
601 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
602 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
603 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
604 all those parameters. This option is useful for old MS-DOS disk
608 DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
609 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
610 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
615 @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}]
617 Define a new file system device. Valid options are:
620 This option specifies the fs driver backend to use.
621 Currently "local", "handle" and "proxy" file system drivers are supported.
623 Specifies identifier for this device
624 @item path=@var{path}
625 Specifies the export path for the file system device. Files under
626 this path will be available to the 9p client on the guest.
627 @item security_model=@var{security_model}
628 Specifies the security model to be used for this export path.
629 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
630 In "passthrough" security model, files are stored using the same
631 credentials as they are created on the guest. This requires QEMU
632 to run as root. In "mapped-xattr" security model, some of the file
633 attributes like uid, gid, mode bits and link target are stored as
634 file attributes. For "mapped-file" these attributes are stored in the
635 hidden .virtfs_metadata directory. Directories exported by this security model cannot
636 interact with other unix tools. "none" security model is same as
637 passthrough except the sever won't report failures
if it fails to
638 set file attributes like ownership
. Security model is mandatory
639 only
for local fsdriver
. Other
fsdrivers (like handle
, proxy
) don
't take
640 security model as a parameter.
641 @item writeout=@var{writeout}
642 This is an optional argument. The only supported value is "immediate".
643 This means that host page cache will be used to read and write data but
644 write notification will be sent to the guest only when the data has been
645 reported as written by the storage subsystem.
647 Enables exporting 9p share as a readonly mount for guests. By default
648 read-write access is given.
649 @item socket=@var{socket}
650 Enables proxy filesystem driver to use passed socket file for communicating
651 with virtfs-proxy-helper
652 @item sock_fd=@var{sock_fd}
653 Enables proxy filesystem driver to use passed socket descriptor for
654 communicating with virtfs-proxy-helper. Usually a helper like libvirt
655 will create socketpair and pass one of the fds as sock_fd
658 -fsdev option is used along with -device driver "virtio-9p-pci".
659 @item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
660 Options for virtio-9p-pci driver are:
663 Specifies the id value specified along with -fsdev option
664 @item mount_tag=@var{mount_tag}
665 Specifies the tag name to be used by the guest to mount this export point
670 DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
671 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
672 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
677 @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}]
680 The general form of a Virtual File system pass-through options are:
683 This option specifies the fs driver backend to use.
684 Currently "local", "handle" and "proxy" file system drivers are supported.
686 Specifies identifier for this device
687 @item path=@var{path}
688 Specifies the export path for the file system device. Files under
689 this path will be available to the 9p client on the guest.
690 @item security_model=@var{security_model}
691 Specifies the security model to be used for this export path.
692 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
693 In "passthrough" security model, files are stored using the same
694 credentials as they are created on the guest. This requires QEMU
695 to run as root. In "mapped-xattr" security model, some of the file
696 attributes like uid, gid, mode bits and link target are stored as
697 file attributes. For "mapped-file" these attributes are stored in the
698 hidden .virtfs_metadata directory. Directories exported by this security model cannot
699 interact with other unix tools. "none" security model is same as
700 passthrough except the sever won't report failures
if it fails to
701 set file attributes like ownership
. Security model is mandatory only
702 for local fsdriver
. Other
fsdrivers (like handle
, proxy
) don
't take security
703 model as a parameter.
704 @item writeout=@var{writeout}
705 This is an optional argument. The only supported value is "immediate".
706 This means that host page cache will be used to read and write data but
707 write notification will be sent to the guest only when the data has been
708 reported as written by the storage subsystem.
710 Enables exporting 9p share as a readonly mount for guests. By default
711 read-write access is given.
712 @item socket=@var{socket}
713 Enables proxy filesystem driver to use passed socket file for
714 communicating with virtfs-proxy-helper. Usually a helper like libvirt
715 will create socketpair and pass one of the fds as sock_fd
717 Enables proxy filesystem driver to use passed 'sock_fd
' as the socket
718 descriptor for interfacing with virtfs-proxy-helper
722 DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
723 "-virtfs_synth Create synthetic file system image\n",
727 @findex -virtfs_synth
728 Create synthetic file system image
736 DEFHEADING(USB options:)
741 DEF("usb", 0, QEMU_OPTION_usb,
742 "-usb enable the USB driver (will be the default soon)\n",
747 Enable the USB driver (will be the default soon)
750 DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
751 "-usbdevice name add the host or guest USB device 'name
'\n",
755 @item -usbdevice @var{devname}
757 Add the USB device @var{devname}. @xref{usb_devices}.
762 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
765 Pointer device that uses absolute coordinates (like a touchscreen). This
766 means QEMU is able to report the mouse position without having to grab the
767 mouse. Also overrides the PS/2 mouse emulation when activated.
769 @item disk:[format=@var{format}]:@var{file}
770 Mass storage device based on file. The optional @var{format} argument
771 will be used rather than detecting the format. Can be used to specifiy
772 @code{format=raw} to avoid interpreting an untrusted format header.
774 @item host:@var{bus}.@var{addr}
775 Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
777 @item host:@var{vendor_id}:@var{product_id}
778 Pass through the host device identified by @var{vendor_id}:@var{product_id}
781 @item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
782 Serial converter to host character device @var{dev}, see @code{-serial} for the
786 Braille device. This will use BrlAPI to display the braille output on a real
789 @item net:@var{options}
790 Network adapter that supports CDC ethernet and RNDIS protocols.
800 DEFHEADING(Display options:)
805 DEF("display", HAS_ARG, QEMU_OPTION_display,
806 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
807 " [,window_close=on|off]|curses|none|\n"
808 " vnc=<display>[,<optargs>]\n"
809 " select display type\n", QEMU_ARCH_ALL)
811 @item -display @var{type}
813 Select type of display to use. This option is a replacement for the
814 old style -sdl/-curses/... options. Valid values for @var{type} are
817 Display video output via SDL (usually in a separate graphics
818 window; see the SDL documentation for other possibilities).
820 Display video output via curses. For graphics device models which
821 support a text mode, QEMU can display this output using a
822 curses/ncurses interface. Nothing is displayed when the graphics
823 device is in graphical mode or if the graphics device does not support
824 a text mode. Generally only the VGA device models support text mode.
826 Do not display video output. The guest will still see an emulated
827 graphics card, but its output will not be displayed to the QEMU
828 user. This option differs from the -nographic option in that it
829 only affects what is done with video output; -nographic also changes
830 the destination of the serial and parallel port data.
832 Start a VNC server on display <arg>
836 DEF("nographic", 0, QEMU_OPTION_nographic,
837 "-nographic disable graphical output and redirect serial I/Os to console\n",
842 Normally, QEMU uses SDL to display the VGA output. With this option,
843 you can totally disable graphical output so that QEMU is a simple
844 command line application. The emulated serial port is redirected on
845 the console. Therefore, you can still use QEMU to debug a Linux kernel
846 with a serial console.
849 DEF("curses", 0, QEMU_OPTION_curses,
850 "-curses use a curses/ncurses interface instead of SDL\n",
855 Normally, QEMU uses SDL to display the VGA output. With this option,
856 QEMU can display the VGA output when in text mode using a
857 curses/ncurses interface. Nothing is displayed in graphical mode.
860 DEF("no-frame", 0, QEMU_OPTION_no_frame,
861 "-no-frame open SDL window without a frame and window decorations\n",
866 Do not use decorations for SDL windows and start them using the whole
867 available screen space. This makes the using QEMU in a dedicated desktop
868 workspace more convenient.
871 DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
872 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
877 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
878 affects the special keys (for fullscreen, monitor-mode switching, etc).
881 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
882 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
887 Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
888 affects the special keys (for fullscreen, monitor-mode switching, etc).
891 DEF("no-quit", 0, QEMU_OPTION_no_quit,
892 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL)
896 Disable SDL window close capability.
899 DEF("sdl", 0, QEMU_OPTION_sdl,
900 "-sdl enable SDL\n", QEMU_ARCH_ALL)
907 DEF("spice", HAS_ARG, QEMU_OPTION_spice,
908 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
909 " [,x509-key-file=<file>][,x509-key-password=<file>]\n"
910 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
911 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6]\n"
912 " [,tls-ciphers=<list>]\n"
913 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
914 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
915 " [,sasl][,password=<secret>][,disable-ticketing]\n"
916 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
917 " [,jpeg-wan-compression=[auto|never|always]]\n"
918 " [,zlib-glz-wan-compression=[auto|never|always]]\n"
919 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
920 " [,agent-mouse=[on|off]][,playback-compression=[on|off]]\n"
921 " [,seamless-migration=[on|off]]\n"
923 " at least one of {port, tls-port} is mandatory\n",
926 @item -spice @var{option}[,@var{option}[,...]]
928 Enable the spice remote desktop protocol. Valid options are
933 Set the TCP port spice is listening on for plaintext channels.
936 Set the IP address spice is listening on. Default is any address.
940 Force using the specified IP version.
942 @item password=<secret>
943 Set the password you need to authenticate.
946 Require that the client use SASL to authenticate with the spice.
947 The exact choice of authentication method used is controlled from the
948 system / user's SASL configuration file
for the
'qemu' service
. This
949 is typically found
in /etc
/sasl2
/qemu
.conf
. If running QEMU as an
950 unprivileged user
, an environment variable SASL_CONF_PATH can be used
951 to make it search alternate locations
for the service config
.
952 While some SASL auth methods can also provide data
encryption (eg GSSAPI
),
953 it is recommended that SASL always be combined with the
'tls' and
954 'x509' settings to enable use of SSL and server certificates
. This
955 ensures a data encryption preventing compromise of authentication
958 @item disable
-ticketing
959 Allow client connects without authentication
.
961 @item disable
-copy
-paste
962 Disable copy paste between the client and the guest
.
965 Set the TCP port spice is listening on
for encrypted channels
.
968 Set the x509 file directory
. Expects same filenames as
-vnc $display
,x509
=$dir
970 @item x509
-key
-file
=<file
>
971 @item x509
-key
-password
=<file
>
972 @item x509
-cert
-file
=<file
>
973 @item x509
-cacert
-file
=<file
>
974 @item x509
-dh
-key
-file
=<file
>
975 The x509 file names can also be configured individually
.
977 @item tls
-ciphers
=<list
>
978 Specify which ciphers to use
.
980 @item tls
-channel
=[main|display|cursor|inputs|record|playback
]
981 @item plaintext
-channel
=[main|display|cursor|inputs|record|playback
]
982 Force specific channel to be used with or without TLS encryption
. The
983 options can be specified multiple times to configure multiple
984 channels
. The special name
"default" can be used to set the
default
985 mode
. For channels which are not explicitly forced into one mode the
986 spice client is allowed to pick tls
/plaintext as he pleases
.
988 @item image
-compression
=[auto_glz|auto_lz|quic|glz|lz|off
]
989 Configure image
compression (lossless
).
992 @item jpeg
-wan
-compression
=[auto|
never|always
]
993 @item zlib
-glz
-wan
-compression
=[auto|
never|always
]
994 Configure wan image
compression (lossy
for slow links
).
997 @item streaming
-video
=[off|all|filter
]
998 Configure video stream detection
. Default is filter
.
1000 @item agent
-mouse
=[on|off
]
1001 Enable
/disable passing mouse events via vdagent
. Default is on
.
1003 @item playback
-compression
=[on|off
]
1004 Enable
/disable audio stream
compression (using celt
0.5.1). Default is on
.
1006 @item seamless
-migration
=[on|off
]
1007 Enable
/disable spice seamless migration
. Default is off
.
1012 DEF("portrait", 0, QEMU_OPTION_portrait
,
1013 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
1018 Rotate graphical output
90 deg
left (only PXA LCD
).
1021 DEF("rotate", HAS_ARG
, QEMU_OPTION_rotate
,
1022 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
1025 @item
-rotate @
var{deg
}
1027 Rotate graphical output some deg
left (only PXA LCD
).
1030 DEF("vga", HAS_ARG
, QEMU_OPTION_vga
,
1031 "-vga [std|cirrus|vmware|qxl|xenfb|none]\n"
1032 " select video card type\n", QEMU_ARCH_ALL
)
1034 @item
-vga @
var{type
}
1036 Select type of VGA card to emulate
. Valid values
for @
var{type
} are
1039 Cirrus Logic GD5446 Video card
. All Windows versions starting from
1040 Windows
95 should recognize and use
this graphic card
. For optimal
1041 performances
, use
16 bit color depth
in the guest and the host OS
.
1042 (This one is the
default)
1044 Standard VGA card with Bochs VBE extensions
. If your guest OS
1045 supports the VESA
2.0 VBE
extensions (e
.g
. Windows XP
) and
if you want
1046 to use high resolution
modes (>= 1280x1024x16
) then you should use
1049 VMWare SVGA
-II compatible adapter
. Use it
if you have sufficiently
1050 recent XFree86
/XOrg server or Windows guest with a driver
for this
1053 QXL paravirtual graphic card
. It is VGA
compatible (including VESA
1054 2.0 VBE support
). Works best with qxl guest drivers installed though
.
1055 Recommended choice when
using the spice protocol
.
1061 DEF("full-screen", 0, QEMU_OPTION_full_screen
,
1062 "-full-screen start in full screen\n", QEMU_ARCH_ALL
)
1065 @findex
-full
-screen
1066 Start
in full screen
.
1069 DEF("g", 1, QEMU_OPTION_g
,
1070 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
1071 QEMU_ARCH_PPC | QEMU_ARCH_SPARC
)
1073 @item
-g @
var{width
}x@
var{height
}[x@
var{depth
}]
1075 Set the initial graphical resolution and
depth (PPC
, SPARC only
).
1078 DEF("vnc", HAS_ARG
, QEMU_OPTION_vnc
,
1079 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL
)
1081 @item
-vnc @
var{display
}[,@
var{option
}[,@
var{option
}[,...]]]
1083 Normally
, QEMU uses SDL to display the VGA output
. With
this option
,
1084 you can have QEMU listen on VNC display @
var{display
} and redirect the VGA
1085 display over the VNC session
. It is very useful to enable the usb
1086 tablet device when
using this option (option @option
{-usbdevice
1087 tablet
}). When
using the VNC display
, you must use the @option
{-k
}
1088 parameter to set the keyboard layout
if you are not
using en
-us
. Valid
1089 syntax
for the @
var{display
} is
1093 @item @
var{host
}:@
var{d
}
1095 TCP connections will only be allowed from @
var{host
} on display @
var{d
}.
1096 By convention the TCP port is
5900+@
var{d
}. Optionally
, @
var{host
} can
1097 be omitted
in which
case the server will accept connections from any host
.
1099 @item unix
:@
var{path
}
1101 Connections will be allowed over UNIX domain sockets where @
var{path
} is the
1102 location of a unix socket to listen
for connections on
.
1106 VNC is initialized but not started
. The monitor @code
{change
} command
1107 can be used to later start the VNC server
.
1111 Following the @
var{display
} value there may be one or more @
var{option
} flags
1112 separated by commas
. Valid options are
1118 Connect to a listening VNC client via a ``reverse
'' connection
. The
1119 client is specified by the @
var{display
}. For reverse network
1120 connections (@
var{host
}:@
var{d
},@code
{reverse
}), the @
var{d
} argument
1121 is a TCP port number
, not a display number
.
1125 Opens an additional TCP listening port dedicated to VNC Websocket connections
.
1126 By definition the Websocket port is
5700+@
var{display
}. If @
var{host
} is
1127 specified connections will only be allowed from
this host
.
1128 As an alternative the Websocket port could be specified by
using
1129 @code
{websocket
}=@
var{port
}.
1133 Require that password based authentication is used
for client connections
.
1135 The password must be set separately
using the @code
{set_password
} command
in
1136 the @ref
{pcsys_monitor
}. The syntax to change your password is
:
1137 @code
{set_password
<protocol
> <password
>} where
<protocol
> could be either
1140 If you would like to change
<protocol
> password expiration
, you should use
1141 @code
{expire_password
<protocol
> <expiration
-time
>} where expiration time could
1142 be one of the following options
: now
, never, +seconds or UNIX time of
1143 expiration
, e
.g
. +60 to make password expire
in 60 seconds
, or
1335196800
1144 to make password expire on
"Mon Apr 23 12:00:00 EDT 2012" (UNIX time
for this
1147 You can also use keywords
"now" or
"never" for the expiration time to
1148 allow
<protocol
> password to expire immediately or
never expire
.
1152 Require that client use TLS when communicating with the VNC server
. This
1153 uses anonymous TLS credentials so is susceptible to a man
-in-the
-middle
1154 attack
. It is recommended that
this option be combined with either the
1155 @option
{x509
} or @option
{x509verify
} options
.
1157 @item x509
=@
var{/path
/to
/certificate
/dir
}
1159 Valid
if @option
{tls
} is specified
. Require that x509 credentials are used
1160 for negotiating the TLS session
. The server will send its x509 certificate
1161 to the client
. It is recommended that a password be set on the VNC server
1162 to provide authentication of the client when
this is used
. The path following
1163 this option specifies where the x509 certificates are to be loaded from
.
1164 See the @ref
{vnc_security
} section
for details on generating certificates
.
1166 @item x509verify
=@
var{/path
/to
/certificate
/dir
}
1168 Valid
if @option
{tls
} is specified
. Require that x509 credentials are used
1169 for negotiating the TLS session
. The server will send its x509 certificate
1170 to the client
, and request that the client send its own x509 certificate
.
1171 The server will validate the client
's certificate against the CA certificate,
1172 and reject clients when validation fails. If the certificate authority is
1173 trusted, this is a sufficient authentication mechanism. You may still wish
1174 to set a password on the VNC server as a second authentication layer. The
1175 path following this option specifies where the x509 certificates are to
1176 be loaded from. See the @ref{vnc_security} section for details on generating
1181 Require that the client use SASL to authenticate with the VNC server.
1182 The exact choice of authentication method used is controlled from the
1183 system / user's SASL configuration file
for the
'qemu' service
. This
1184 is typically found
in /etc
/sasl2
/qemu
.conf
. If running QEMU as an
1185 unprivileged user
, an environment variable SASL_CONF_PATH can be used
1186 to make it search alternate locations
for the service config
.
1187 While some SASL auth methods can also provide data
encryption (eg GSSAPI
),
1188 it is recommended that SASL always be combined with the
'tls' and
1189 'x509' settings to enable use of SSL and server certificates
. This
1190 ensures a data encryption preventing compromise of authentication
1191 credentials
. See the @ref
{vnc_security
} section
for details on
using
1192 SASL authentication
.
1196 Turn on access control lists
for checking of the x509 client certificate
1197 and SASL party
. For x509 certs
, the ACL check is made against the
1198 certificate
's distinguished name. This is something that looks like
1199 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1200 made against the username, which depending on the SASL plugin, may
1201 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1202 When the @option{acl} flag is set, the initial access list will be
1203 empty, with a @code{deny} policy. Thus no one will be allowed to
1204 use the VNC server until the ACLs have been loaded. This can be
1205 achieved using the @code{acl} monitor command.
1209 Enable lossy compression methods (gradient, JPEG, ...). If this
1210 option is set, VNC client may receive lossy framebuffer updates
1211 depending on its encoding settings. Enabling this option can save
1212 a lot of bandwidth at the expense of quality.
1216 Disable adaptive encodings. Adaptive encodings are enabled by default.
1217 An adaptive encoding will try to detect frequently updated screen regions,
1218 and send updates in these regions using a lossy encoding (like JPEG).
1219 This can be really helpful to save bandwidth when playing videos. Disabling
1220 adaptive encodings allows to restore the original static behavior of encodings
1223 @item share=[allow-exclusive|force-shared|ignore]
1225 Set display sharing policy. 'allow
-exclusive
' allows clients to ask
1226 for exclusive access. As suggested by the rfb spec this is
1227 implemented by dropping other connections. Connecting multiple
1228 clients in parallel requires all clients asking for a shared session
1229 (vncviewer: -shared switch). This is the default. 'force
-shared
'
1230 disables exclusive client access. Useful for shared desktop sessions,
1231 where you don't want someone forgetting specify
-shared disconnect
1232 everybody
else. 'ignore' completely ignores the shared flag and
1233 allows everybody connect unconditionally
. Doesn
't conform to the rfb
1234 spec but is traditional QEMU behavior.
1242 ARCHHEADING(, QEMU_ARCH_I386)
1244 ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1249 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1250 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1255 Use it when installing Windows 2000 to avoid a disk full bug. After
1256 Windows 2000 is installed, you no longer need this option (this option
1257 slows down the IDE transfers).
1260 HXCOMM Deprecated by -rtc
1261 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1263 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1264 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1267 @item -no-fd-bootchk
1268 @findex -no-fd-bootchk
1269 Disable boot signature checking for floppy disks in Bochs BIOS. It may
1270 be needed to boot from old floppy disks.
1271 TODO: check reference to Bochs BIOS.
1274 DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1275 "-no-acpi disable ACPI\n", QEMU_ARCH_I386)
1279 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1280 it if your guest OS complains about ACPI problems (PC target machine
1284 DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1285 "-no-hpet disable HPET\n", QEMU_ARCH_I386)
1289 Disable HPET support.
1292 DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1293 "-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"
1294 " ACPI table description\n", QEMU_ARCH_I386)
1296 @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}]...]
1298 Add ACPI table with specified header fields and context from specified files.
1299 For file=, take whole ACPI table from the specified files, including all
1300 ACPI headers (possible overridden by other options).
1301 For data=, only data
1302 portion of the table is used, all header information is specified in the
1306 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1307 "-smbios file=binary\n"
1308 " load SMBIOS entry from binary file\n"
1309 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1310 " specify SMBIOS type 0 fields\n"
1311 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1312 " [,uuid=uuid][,sku=str][,family=str]\n"
1313 " specify SMBIOS type 1 fields\n", QEMU_ARCH_I386)
1315 @item -smbios file=@var{binary}
1317 Load SMBIOS entry from binary file.
1319 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}]
1320 Specify SMBIOS type 0 fields
1322 @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}]
1323 Specify SMBIOS type 1 fields
1331 DEFHEADING(Network options:)
1336 HXCOMM Legacy slirp options (now moved to -net user):
1338 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1339 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1340 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1342 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1346 DEF("net", HAS_ARG, QEMU_OPTION_net,
1347 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
1348 " create a new Network Interface Card and connect it to VLAN 'n
'\n"
1350 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=on|off]\n"
1351 " [,hostname=host][,dhcpstart=addr][,dns=addr][,dnssearch=domain][,tftp=dir]\n"
1352 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1354 "[,smb=dir[,smbserver=addr]]\n"
1356 " connect the user mode network stack to VLAN 'n
', configure its\n"
1357 " DHCP server and enabled optional services\n"
1360 "-net tap[,vlan=n][,name=str],ifname=name\n"
1361 " connect the host TAP network interface to VLAN 'n
'\n"
1363 "-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]\n"
1364 " connect the host TAP network interface to VLAN 'n
'\n"
1365 " use network scripts 'file
' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1366 " to configure it and 'dfile
' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1367 " to deconfigure it\n"
1368 " use '[down
]script
=no
' to disable script execution\n"
1369 " use network helper 'helper
' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1371 " use 'fd
=h
' to connect to an already opened TAP interface\n"
1372 " use 'fds
=x
:y
:...:z
' to connect to already opened multiqueue capable TAP interfaces\n"
1373 " use 'sndbuf
=nbytes
' to limit the size of the send buffer (the\n"
1374 " default is disabled 'sndbuf
=0' to enable flow control set 'sndbuf
=1048576')\n"
1375 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1376 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1377 " use vhost=on to enable experimental in kernel accelerator\n"
1378 " (only has effect for virtio guests which use MSIX)\n"
1379 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1380 " use 'vhostfd
=h
' to connect to an already opened vhost net device\n"
1381 " use 'vhostfds
=x
:y
:...:z to connect to multiple already opened vhost net devices
\n"
1382 "-net bridge
[,vlan
=n
][,name
=str
][,br
=bridge
][,helper
=helper
]\n"
1383 " connects a host TAP network
interface to a host bridge device
'br'\n"
1384 " (default=" DEFAULT_BRIDGE_INTERFACE ") using the program
'helper'\n"
1385 " (default=" DEFAULT_BRIDGE_HELPER ")\n"
1387 "-net socket
[,vlan
=n
][,name
=str
][,fd
=h
][,listen
=[host
]:port
][,connect
=host
:port
]\n"
1388 " connect the vlan
'n' to another VLAN
using a socket connection
\n"
1389 "-net socket
[,vlan
=n
][,name
=str
][,fd
=h
][,mcast
=maddr
:port
[,localaddr
=addr
]]\n"
1390 " connect the vlan
'n' to multicast maddr and port
\n"
1391 " use
'localaddr=addr' to specify the host address to send packets from
\n"
1392 "-net socket
[,vlan
=n
][,name
=str
][,fd
=h
][,udp
=host
:port
][,localaddr
=host
:port
]\n"
1393 " connect the vlan
'n' to another VLAN
using an UDP tunnel
\n"
1395 "-net vde
[,vlan
=n
][,name
=str
][,sock
=socketpath
][,port
=n
][,group
=groupname
][,mode
=octalmode
]\n"
1396 " connect the vlan
'n' to port
'n' of a vde
switch running
\n"
1397 " on host and listening
for incoming connections on
'socketpath'.\n"
1398 " Use group
'groupname' and mode
'octalmode' to change
default\n"
1399 " ownership and permissions
for communication port
.\n"
1401 "-net dump
[,vlan
=n
][,file
=f
][,len
=n
]\n"
1402 " dump traffic on vlan
'n' to file
'f' (max n bytes per packet
)\n"
1403 "-net none use it alone to have zero network devices
. If no
-net option
\n"
1404 " is provided
, the
default is
'-net nic -net user'\n", QEMU_ARCH_ALL)
1405 DEF("netdev
", HAS_ARG, QEMU_OPTION_netdev,
1416 "hubport
],id
=str
[,option
][,option
][,...]\n", QEMU_ARCH_ALL)
1418 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1420 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1421 = 0 is the default). The NIC is an e1000 by default on the PC
1422 target. Optionally, the MAC address can be changed to @var{mac}, the
1423 device address set to @var{addr} (PCI cards only),
1424 and a @var{name} can be assigned for use in monitor commands.
1425 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1426 that the card should have; this option currently only affects virtio cards; set
1427 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1428 NIC is created. QEMU can emulate several different models of network card.
1429 Valid values for @var{type} are
1430 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1431 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1432 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1433 Not all devices are supported on all targets. Use @code{-net nic,model=help}
1434 for a list of available devices for your target.
1436 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
1438 @item -net user[,@var{option}][,@var{option}][,...]
1439 Use the user mode network stack which requires no administrator
1440 privilege to run. Valid options are:
1444 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1447 @item name=@var{name}
1448 Assign symbolic name for use in monitor commands.
1450 @item net=@var{addr}[/@var{mask}]
1451 Set IP network address the guest will see. Optionally specify the netmask,
1452 either in the form a.b.c.d or as number of valid top-most bits. Default is
1455 @item host=@var{addr}
1456 Specify the guest-visible address of the host. Default is the 2nd IP in the
1457 guest network, i.e. x.x.x.2.
1459 @item restrict=on|off
1460 If this option is enabled, the guest will be isolated, i.e. it will not be
1461 able to contact the host and no guest IP packets will be routed over the host
1462 to the outside. This option does not affect any explicitly set forwarding rules.
1464 @item hostname=@var{name}
1465 Specifies the client hostname reported by the built-in DHCP server.
1467 @item dhcpstart=@var{addr}
1468 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1469 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1471 @item dns=@var{addr}
1472 Specify the guest-visible address of the virtual nameserver. The address must
1473 be different from the host address. Default is the 3rd IP in the guest network,
1476 @item dnssearch=@var{domain}
1477 Provides an entry for the domain-search list sent by the built-in
1478 DHCP server. More than one domain suffix can be transmitted by specifying
1479 this option multiple times. If supported, this will cause the guest to
1480 automatically try to append the given domain suffix(es) in case a domain name
1481 can not be resolved.
1485 qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
1488 @item tftp=@var{dir}
1489 When using the user mode network stack, activate a built-in TFTP
1490 server. The files in @var{dir} will be exposed as the root of a TFTP server.
1491 The TFTP client on the guest must be configured in binary mode (use the command
1492 @code{bin} of the Unix TFTP client).
1494 @item bootfile=@var{file}
1495 When using the user mode network stack, broadcast @var{file} as the BOOTP
1496 filename. In conjunction with @option{tftp}, this can be used to network boot
1497 a guest from a local directory.
1499 Example (using pxelinux):
1501 qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1504 @item smb=@var{dir}[,smbserver=@var{addr}]
1505 When using the user mode network stack, activate a built-in SMB
1506 server so that Windows OSes can access to the host files in @file{@var{dir}}
1507 transparently. The IP address of the SMB server can be set to @var{addr}. By
1508 default the 4th IP in the guest network is used, i.e. x.x.x.4.
1510 In the guest Windows OS, the line:
1514 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1515 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1517 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
1519 Note that a SAMBA server must be installed on the host OS.
1520 QEMU was tested successfully with smbd versions from Red Hat 9,
1521 Fedora Core 3 and OpenSUSE 11.x.
1523 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1524 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1525 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1526 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1527 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1528 be bound to a specific host interface. If no connection type is set, TCP is
1529 used. This option can be given multiple times.
1531 For example, to redirect host X11 connection from screen 1 to guest
1532 screen 0, use the following:
1536 qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1537 # this host xterm should open in the guest X11 server
1541 To redirect telnet connections from host port 5555 to telnet port on
1542 the guest, use the following:
1546 qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
1547 telnet localhost 5555
1550 Then when you use on the host @code{telnet localhost 5555}, you
1551 connect to the guest telnet server.
1553 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1554 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
1555 Forward guest TCP connections to the IP address @var{server} on port @var{port}
1556 to the character device @var{dev} or to a program executed by @var{cmd:command}
1557 which gets spawned for each connection. This option can be given multiple times.
1559 You can either use a chardev directly and have that one used throughout QEMU's
1560 lifetime, like in the following example:
1563 # open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
1564 # the guest accesses it
1565 qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...]
1568 Or you can execute a command on every TCP connection established by the guest,
1569 so that QEMU behaves similar to an inetd process for that virtual server:
1572 # call "netcat
10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
1573 # and connect the TCP stream to its stdin/stdout
1574 qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
1579 Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
1580 processed and applied to -net user. Mixing them with the new configuration
1581 syntax gives undefined results. Their use for new applications is discouraged
1582 as they will be removed from future versions.
1584 @item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1585 @item -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1586 Connect the host TAP network interface @var{name} to VLAN @var{n}.
1588 Use the network script @var{file} to configure it and the network script
1589 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
1590 automatically provides one. The default network configure script is
1591 @file{/etc/qemu-ifup} and the default network deconfigure script is
1592 @file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
1593 to disable script execution.
1595 If running QEMU as an unprivileged user, use the network helper
1596 @var{helper} to configure the TAP interface. The default network
1597 helper executable is @file{/usr/local/libexec/qemu-bridge-helper}.
1599 @option{fd}=@var{h} can be used to specify the handle of an already
1600 opened host TAP interface.
1605 #launch a QEMU instance with the default network script
1606 qemu-system-i386 linux.img -net nic -net tap
1610 #launch a QEMU instance with two NICs, each one connected
1612 qemu-system-i386 linux.img \
1613 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
1614 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
1618 #launch a QEMU instance with the default network helper to
1619 #connect a TAP device to bridge br0
1620 qemu-system-i386 linux.img \
1621 -net nic -net tap,"helper
=/usr
/local
/libexec
/qemu
-bridge
-helper
"
1624 @item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
1625 @item -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
1626 Connect a host TAP network interface to a host bridge device.
1628 Use the network helper @var{helper} to configure the TAP interface and
1629 attach it to the bridge. The default network helper executable is
1630 @file{/usr/local/libexec/qemu-bridge-helper} and the default bridge
1631 device is @file{br0}.
1636 #launch a QEMU instance with the default network helper to
1637 #connect a TAP device to bridge br0
1638 qemu-system-i386 linux.img -net bridge -net nic,model=virtio
1642 #launch a QEMU instance with the default network helper to
1643 #connect a TAP device to bridge qemubr0
1644 qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
1647 @item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1648 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1650 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
1651 machine using a TCP socket connection. If @option{listen} is
1652 specified, QEMU waits for incoming connections on @var{port}
1653 (@var{host} is optional). @option{connect} is used to connect to
1654 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
1655 specifies an already opened TCP socket.
1659 # launch a first QEMU instance
1660 qemu-system-i386 linux.img \
1661 -net nic,macaddr=52:54:00:12:34:56 \
1662 -net socket,listen=:1234
1663 # connect the VLAN 0 of this instance to the VLAN 0
1664 # of the first instance
1665 qemu-system-i386 linux.img \
1666 -net nic,macaddr=52:54:00:12:34:57 \
1667 -net socket,connect=127.0.0.1:1234
1670 @item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1671 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1673 Create a VLAN @var{n} shared with another QEMU virtual
1674 machines using a UDP multicast socket, effectively making a bus for
1675 every QEMU with same multicast address @var{maddr} and @var{port}.
1679 Several QEMU can be running on different hosts and share same bus (assuming
1680 correct multicast setup for these hosts).
1682 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
1683 @url{http://user-mode-linux.sf.net}.
1685 Use @option{fd=h} to specify an already opened UDP multicast socket.
1690 # launch one QEMU instance
1691 qemu-system-i386 linux.img \
1692 -net nic,macaddr=52:54:00:12:34:56 \
1693 -net socket,mcast=230.0.0.1:1234
1694 # launch another QEMU instance on same "bus
"
1695 qemu-system-i386 linux.img \
1696 -net nic,macaddr=52:54:00:12:34:57 \
1697 -net socket,mcast=230.0.0.1:1234
1698 # launch yet another QEMU instance on same "bus
"
1699 qemu-system-i386 linux.img \
1700 -net nic,macaddr=52:54:00:12:34:58 \
1701 -net socket,mcast=230.0.0.1:1234
1704 Example (User Mode Linux compat.):
1706 # launch QEMU instance (note mcast address selected
1708 qemu-system-i386 linux.img \
1709 -net nic,macaddr=52:54:00:12:34:56 \
1710 -net socket,mcast=239.192.168.1:1102
1712 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
1715 Example (send packets from host's 1.2.3.4):
1717 qemu-system-i386 linux.img \
1718 -net nic,macaddr=52:54:00:12:34:56 \
1719 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
1722 @item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1723 @item -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1724 Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
1725 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
1726 and MODE @var{octalmode} to change default ownership and permissions for
1727 communication port. This option is only available if QEMU has been compiled
1728 with vde support enabled.
1733 vde_switch -F -sock /tmp/myswitch
1734 # launch QEMU instance
1735 qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch
1738 @item -netdev hubport,id=@var{id},hubid=@var{hubid}
1740 Create a hub port on QEMU "vlan
" @var{hubid}.
1742 The hubport netdev lets you connect a NIC to a QEMU "vlan
" instead of a single
1743 netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the
1744 required hub automatically.
1746 @item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
1747 Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
1748 At most @var{len} bytes (64k by default) per packet are stored. The file format is
1749 libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
1752 Indicate that no network devices should be configured. It is used to
1753 override the default configuration (@option{-net nic -net user}) which
1754 is activated if no @option{-net} options are provided.
1762 DEFHEADING(Character device options:)
1765 The general form of a character device option is:
1769 DEF("chardev
", HAS_ARG, QEMU_OPTION_chardev,
1770 "-chardev
null,id
=id
[,mux
=on|off
]\n"
1771 "-chardev socket
,id
=id
[,host
=host
],port
=host
[,to
=to
][,ipv4
][,ipv6
][,nodelay
]\n"
1772 " [,server
][,nowait
][,telnet
][,mux
=on|off
] (tcp
)\n"
1773 "-chardev socket
,id
=id
,path
=path
[,server
][,nowait
][,telnet
],[mux
=on|off
] (unix
)\n"
1774 "-chardev udp
,id
=id
[,host
=host
],port
=port
[,localaddr
=localaddr
]\n"
1775 " [,localport
=localport
][,ipv4
][,ipv6
][,mux
=on|off
]\n"
1776 "-chardev msmouse
,id
=id
[,mux
=on|off
]\n"
1777 "-chardev vc
,id
=id
[[,width
=width
][,height
=height
]][[,cols
=cols
][,rows
=rows
]]\n"
1779 "-chardev ringbuf
,id
=id
[,size
=size
]\n"
1780 "-chardev file
,id
=id
,path
=path
[,mux
=on|off
]\n"
1781 "-chardev pipe
,id
=id
,path
=path
[,mux
=on|off
]\n"
1783 "-chardev console
,id
=id
[,mux
=on|off
]\n"
1784 "-chardev serial
,id
=id
,path
=path
[,mux
=on|off
]\n"
1786 "-chardev pty
,id
=id
[,mux
=on|off
]\n"
1787 "-chardev stdio
,id
=id
[,mux
=on|off
][,signal
=on|off
]\n"
1789 #ifdef CONFIG_BRLAPI
1790 "-chardev braille
,id
=id
[,mux
=on|off
]\n"
1792 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
1793 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
1794 "-chardev serial
,id
=id
,path
=path
[,mux
=on|off
]\n"
1795 "-chardev tty
,id
=id
,path
=path
[,mux
=on|off
]\n"
1797 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
1798 "-chardev parallel
,id
=id
,path
=path
[,mux
=on|off
]\n"
1799 "-chardev parport
,id
=id
,path
=path
[,mux
=on|off
]\n"
1801 #if defined(CONFIG_SPICE)
1802 "-chardev spicevmc
,id
=id
,name
=name
[,debug
=debug
]\n"
1803 "-chardev spiceport
,id
=id
,name
=name
[,debug
=debug
]\n"
1809 @item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
1830 The specific backend will determine the applicable options.
1832 All devices must have an id, which can be any string up to 127 characters long.
1833 It is used to uniquely identify this device in other command line directives.
1835 A character device may be used in multiplexing mode by multiple front-ends.
1836 The key sequence of @key{Control-a} and @key{c} will rotate the input focus
1837 between attached front-ends. Specify @option{mux=on} to enable this mode.
1839 Options to each backend are described below.
1841 @item -chardev null ,id=@var{id}
1842 A void device. This device will not emit any data, and will drop any data it
1843 receives. The null backend does not take any options.
1845 @item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet]
1847 Create a two-way stream socket, which can be either a TCP or a unix socket. A
1848 unix socket will be created if @option{path} is specified. Behaviour is
1849 undefined if TCP options are specified for a unix socket.
1851 @option{server} specifies that the socket shall be a listening socket.
1853 @option{nowait} specifies that QEMU should not block waiting for a client to
1854 connect to a listening socket.
1856 @option{telnet} specifies that traffic on the socket should interpret telnet
1859 TCP and unix socket options are given below:
1863 @item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
1865 @option{host} for a listening socket specifies the local address to be bound.
1866 For a connecting socket species the remote host to connect to. @option{host} is
1867 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
1869 @option{port} for a listening socket specifies the local port to be bound. For a
1870 connecting socket specifies the port on the remote host to connect to.
1871 @option{port} can be given as either a port number or a service name.
1872 @option{port} is required.
1874 @option{to} is only relevant to listening sockets. If it is specified, and
1875 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
1876 to and including @option{to} until it succeeds. @option{to} must be specified
1879 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1880 If neither is specified the socket may use either protocol.
1882 @option{nodelay} disables the Nagle algorithm.
1884 @item unix options: path=@var{path}
1886 @option{path} specifies the local path of the unix socket. @option{path} is
1891 @item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
1893 Sends all traffic from the guest to a remote host over UDP.
1895 @option{host} specifies the remote host to connect to. If not specified it
1896 defaults to @code{localhost}.
1898 @option{port} specifies the port on the remote host to connect to. @option{port}
1901 @option{localaddr} specifies the local address to bind to. If not specified it
1902 defaults to @code{0.0.0.0}.
1904 @option{localport} specifies the local port to bind to. If not specified any
1905 available local port will be used.
1907 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1908 If neither is specified the device may use either protocol.
1910 @item -chardev msmouse ,id=@var{id}
1912 Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
1915 @item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
1917 Connect to a QEMU text console. @option{vc} may optionally be given a specific
1920 @option{width} and @option{height} specify the width and height respectively of
1921 the console, in pixels.
1923 @option{cols} and @option{rows} specify that the console be sized to fit a text
1924 console with the given dimensions.
1926 @item -chardev ringbuf ,id=@var{id} [,size=@var{size}]
1928 Create a ring buffer with fixed size @option{size}.
1929 @var{size} must be a power of two, and defaults to @code{64K}).
1931 @item -chardev file ,id=@var{id} ,path=@var{path}
1933 Log all traffic received from the guest to a file.
1935 @option{path} specifies the path of the file to be opened. This file will be
1936 created if it does not already exist, and overwritten if it does. @option{path}
1939 @item -chardev pipe ,id=@var{id} ,path=@var{path}
1941 Create a two-way connection to the guest. The behaviour differs slightly between
1942 Windows hosts and other hosts:
1944 On Windows, a single duplex pipe will be created at
1945 @file{\\.pipe\@option{path}}.
1947 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
1948 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
1949 received by the guest. Data written by the guest can be read from
1950 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
1953 @option{path} forms part of the pipe path as described above. @option{path} is
1956 @item -chardev console ,id=@var{id}
1958 Send traffic from the guest to QEMU's standard output. @option{console} does not
1961 @option{console} is only available on Windows hosts.
1963 @item -chardev serial ,id=@var{id} ,path=@option{path}
1965 Send traffic from the guest to a serial device on the host.
1967 On Unix hosts serial will actually accept any tty device,
1968 not only serial lines.
1970 @option{path} specifies the name of the serial device to open.
1972 @item -chardev pty ,id=@var{id}
1974 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
1975 not take any options.
1977 @option{pty} is not available on Windows hosts.
1979 @item -chardev stdio ,id=@var{id} [,signal=on|off]
1980 Connect to standard input and standard output of the QEMU process.
1982 @option{signal} controls if signals are enabled on the terminal, that includes
1983 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
1984 default, use @option{signal=off} to disable it.
1986 @option{stdio} is not available on Windows hosts.
1988 @item -chardev braille ,id=@var{id}
1990 Connect to a local BrlAPI server. @option{braille} does not take any options.
1992 @item -chardev tty ,id=@var{id} ,path=@var{path}
1994 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
1995 DragonFlyBSD hosts. It is an alias for @option{serial}.
1997 @option{path} specifies the path to the tty. @option{path} is required.
1999 @item -chardev parallel ,id=@var{id} ,path=@var{path}
2000 @item -chardev parport ,id=@var{id} ,path=@var{path}
2002 @option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2004 Connect to a local parallel port.
2006 @option{path} specifies the path to the parallel port device. @option{path} is
2009 @item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2011 @option{spicevmc} is only available when spice support is built in.
2013 @option{debug} debug level for spicevmc
2015 @option{name} name of spice channel to connect to
2017 Connect to a spice virtual machine channel, such as vdiport.
2019 @item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2021 @option{spiceport} is only available when spice support is built in.
2023 @option{debug} debug level for spicevmc
2025 @option{name} name of spice port to connect to
2027 Connect to a spice port, allowing a Spice client to handle the traffic
2028 identified by a name (preferably a fqdn).
2036 DEFHEADING(Device URL Syntax:)
2039 In addition to using normal file images for the emulated storage devices,
2040 QEMU can also use networked resources such as iSCSI devices. These are
2041 specified using a special URL syntax.
2045 iSCSI support allows QEMU to access iSCSI resources directly and use as
2046 images for the guest storage. Both disk and cdrom images are supported.
2048 Syntax for specifying iSCSI LUNs is
2049 ``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
2051 By default qemu will use the iSCSI initiator-name
2052 'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command
2053 line or a configuration file.
2056 Example (without authentication):
2058 qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
2059 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
2060 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2063 Example (CHAP username/password via URL):
2065 qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
2068 Example (CHAP username/password via environment variables):
2070 LIBISCSI_CHAP_USERNAME="user
" \
2071 LIBISCSI_CHAP_PASSWORD="password
" \
2072 qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2075 iSCSI support is an optional feature of QEMU and only available when
2076 compiled and linked against libiscsi.
2078 DEF("iscsi
", HAS_ARG, QEMU_OPTION_iscsi,
2079 "-iscsi
[user
=user
][,password
=password
]\n"
2080 " [,header
-digest
=CRC32C|CR32C
-NONE|NONE
-CRC32C|NONE
\n"
2081 " [,initiator
-name
=iqn
]\n"
2082 " iSCSI session parameters
\n", QEMU_ARCH_ALL)
2085 iSCSI parameters such as username and password can also be specified via
2086 a configuration file. See qemu-doc for more information and examples.
2089 QEMU supports NBD (Network Block Devices) both using TCP protocol as well
2090 as Unix Domain Sockets.
2092 Syntax for specifying a NBD device using TCP
2093 ``nbd:<server-ip>:<port>[:exportname=<export>]''
2095 Syntax for specifying a NBD device using Unix Domain Sockets
2096 ``nbd:unix:<domain-socket>[:exportname=<export>]''
2101 qemu-system-i386 --drive file=nbd:192.0.2.1:30000
2104 Example for Unix Domain Sockets
2106 qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket
2110 Sheepdog is a distributed storage system for QEMU.
2111 QEMU supports using either local sheepdog devices or remote networked
2114 Syntax for specifying a sheepdog device
2116 sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag]
2121 qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine
2124 See also @url{http://http://www.osrg.net/sheepdog/}.
2127 GlusterFS is an user space distributed file system.
2128 QEMU supports the use of GlusterFS volumes for hosting VM disk images using
2129 TCP, Unix Domain Sockets and RDMA transport protocols.
2131 Syntax for specifying a VM disk image on GlusterFS volume is
2133 gluster[+transport]://[server[:port]]/volname/image[?socket=...]
2139 qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img
2142 See also @url{http://www.gluster.org}.
2149 DEFHEADING(Bluetooth(R) options:)
2154 DEF("bt
", HAS_ARG, QEMU_OPTION_bt, \
2155 "-bt hci
,null dumb bluetooth HCI
- doesn
't respond to commands\n" \
2156 "-bt hci,host[:id]\n" \
2157 " use host's HCI with the given name
\n" \
2158 "-bt hci
[,vlan
=n
]\n" \
2159 " emulate a standard HCI
in virtual scatternet
'n'\n" \
2160 "-bt vhci
[,vlan
=n
]\n" \
2161 " add host computer to virtual scatternet
'n' using VHCI
\n" \
2162 "-bt device
:dev
[,vlan
=n
]\n" \
2163 " emulate a bluetooth device
'dev' in scatternet
'n'\n",
2168 Defines the function of the corresponding Bluetooth HCI. -bt options
2169 are matched with the HCIs present in the chosen machine type. For
2170 example when emulating a machine with only one HCI built into it, only
2171 the first @code{-bt hci[...]} option is valid and defines the HCI's
2172 logic. The Transport Layer is decided by the machine type. Currently
2173 the machines @code{n800} and @code{n810} have one HCI and all other
2177 The following three types are recognized:
2181 (default) The corresponding Bluetooth HCI assumes no internal logic
2182 and will not respond to any HCI commands or emit events.
2184 @item -bt hci,host[:@var{id}]
2185 (@code{bluez} only) The corresponding HCI passes commands / events
2186 to / from the physical HCI identified by the name @var{id} (default:
2187 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
2188 capable systems like Linux.
2190 @item -bt hci[,vlan=@var{n}]
2191 Add a virtual, standard HCI that will participate in the Bluetooth
2192 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
2193 VLANs, devices inside a bluetooth network @var{n} can only communicate
2194 with other devices in the same network (scatternet).
2197 @item -bt vhci[,vlan=@var{n}]
2198 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2199 to the host bluetooth stack instead of to the emulated target. This
2200 allows the host and target machines to participate in a common scatternet
2201 and communicate. Requires the Linux @code{vhci} driver installed. Can
2202 be used as following:
2205 qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2208 @item -bt device:@var{dev}[,vlan=@var{n}]
2209 Emulate a bluetooth device @var{dev} and place it in network @var{n}
2210 (default @code{0}). QEMU can only emulate one type of bluetooth devices
2215 Virtual wireless keyboard implementing the HIDP bluetooth profile.
2225 DEFHEADING(TPM device options:)
2227 DEF("tpmdev
", HAS_ARG, QEMU_OPTION_tpmdev, \
2228 "-tpmdev passthrough
,id
=id
[,path
=path
][,cancel
-path
=path
]\n"
2229 " use path to provide path to a character device
; default is
/dev
/tpm0
\n"
2230 " use cancel
-path to provide path to TPM
's cancel sysfs entry; if\n"
2231 " not provided it will be searched for in /sys/class/misc/tpm?/device\n",
2235 The general form of a TPM device option is:
2238 @item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
2240 Backend type must be:
2241 @option{passthrough}.
2243 The specific backend type will determine the applicable options.
2244 The @code{-tpmdev} option creates the TPM backend and requires a
2245 @code{-device} option that specifies the TPM frontend interface model.
2247 Options to each backend are described below.
2249 Use 'help
' to print all available TPM backend types.
2254 @item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path}
2256 (Linux-host only) Enable access to the host's TPM
using the passthrough
2259 @option
{path
} specifies the path to the host
's TPM device, i.e., on
2260 a Linux host this would be @code{/dev/tpm0}.
2261 @option{path} is optional and by default @code{/dev/tpm0} is used.
2263 @option{cancel-path} specifies the path to the host TPM device's sysfs
2264 entry allowing
for cancellation of an ongoing TPM command
.
2265 @option
{cancel
-path
} is optional and by
default QEMU will search
for the
2268 Some notes about
using the host
's TPM with the passthrough driver:
2270 The TPM device accessed by the passthrough driver must not be
2271 used by any other application on the host.
2273 Since the host's
firmware (BIOS
/UEFI
) has already initialized the TPM
,
2274 the VM
's firmware (BIOS/UEFI) will not be able to initialize the
2275 TPM again and may therefore not show a TPM-specific menu that would
2276 otherwise allow the user to configure the TPM, e.g., allow the user to
2277 enable/disable or activate/deactivate the TPM.
2278 Further, if TPM ownership is released from within a VM then the host's TPM
2279 will get disabled and deactivated
. To enable and activate the
2280 TPM again afterwards
, the host has to be rebooted and the user is
2281 required to enter the firmware
's menu to enable and activate the TPM.
2282 If the TPM is left disabled and/or deactivated most TPM commands will fail.
2284 To create a passthrough TPM use the following two options:
2286 -tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
2288 Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
2289 @code{tpmdev=tpm0} in the device option.
2299 DEFHEADING(Linux/Multiboot boot specific:)
2302 When using these options, you can use a given Linux or Multiboot
2303 kernel without installing it in the disk image. It can be useful
2304 for easier testing of various kernels.
2309 DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
2310 "-kernel bzImage use 'bzImage
' as kernel image\n", QEMU_ARCH_ALL)
2312 @item -kernel @var{bzImage}
2314 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2315 or in multiboot format.
2318 DEF("append", HAS_ARG, QEMU_OPTION_append, \
2319 "-append cmdline use 'cmdline
' as kernel command line\n", QEMU_ARCH_ALL)
2321 @item -append @var{cmdline}
2323 Use @var{cmdline} as kernel command line
2326 DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
2327 "-initrd file use 'file
' as initial ram disk\n", QEMU_ARCH_ALL)
2329 @item -initrd @var{file}
2331 Use @var{file} as initial ram disk.
2333 @item -initrd "@var{file1} arg=foo,@var{file2}"
2335 This syntax is only available with multiboot.
2337 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
2341 DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
2342 "-dtb file use 'file
' as device tree image\n", QEMU_ARCH_ALL)
2344 @item -dtb @var{file}
2346 Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
2355 DEFHEADING(Debug/Expert options:)
2360 DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
2361 "-serial dev redirect the serial port to char device 'dev
'\n",
2364 @item -serial @var{dev}
2366 Redirect the virtual serial port to host character device
2367 @var{dev}. The default device is @code{vc} in graphical mode and
2368 @code{stdio} in non graphical mode.
2370 This option can be used several times to simulate up to 4 serial
2373 Use @code{-serial none} to disable all serial ports.
2375 Available character devices are:
2377 @item vc[:@var{W}x@var{H}]
2378 Virtual console. Optionally, a width and height can be given in pixel with
2382 It is also possible to specify width or height in characters:
2387 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
2389 No device is allocated.
2393 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
2394 parameters are set according to the emulated ones.
2395 @item /dev/parport@var{N}
2396 [Linux only, parallel port only] Use host parallel port
2397 @var{N}. Currently SPP and EPP parallel port features can be used.
2398 @item file:@var{filename}
2399 Write output to @var{filename}. No character can be read.
2401 [Unix only] standard input/output
2402 @item pipe:@var{filename}
2403 name pipe @var{filename}
2405 [Windows only] Use host serial port @var{n}
2406 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
2407 This implements UDP Net Console.
2408 When @var{remote_host} or @var{src_ip} are not specified
2409 they default to @code{0.0.0.0}.
2410 When not using a specified @var{src_port} a random port is automatically chosen.
2412 If you just want a simple readonly console you can use @code{netcat} or
2413 @code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
2414 @code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
2415 will appear in the netconsole session.
2417 If you plan to send characters back via netconsole or you want to stop
2418 and start QEMU a lot of times, you should have QEMU use the same
2419 source port each time by using something like @code{-serial
2420 udp::4555@@:4556} to QEMU. Another approach is to use a patched
2421 version of netcat which can listen to a TCP port and send and receive
2422 characters via udp. If you have a patched version of netcat which
2423 activates telnet remote echo and single char transfer, then you can
2424 use the following options to step up a netcat redirector to allow
2425 telnet on port 5555 to access the QEMU port.
2428 -serial udp::4555@@:4556
2429 @item netcat options:
2430 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
2431 @item telnet options:
2435 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay]
2436 The TCP Net Console has two modes of operation. It can send the serial
2437 I/O to a location or wait for a connection from a location. By default
2438 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
2439 the @var{server} option QEMU will wait for a client socket application
2440 to connect to the port before continuing, unless the @code{nowait}
2441 option was specified. The @code{nodelay} option disables the Nagle buffering
2442 algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only
2443 one TCP connection at a time is accepted. You can use @code{telnet} to
2444 connect to the corresponding character device.
2446 @item Example to send tcp console to 192.168.0.2 port 4444
2447 -serial tcp:192.168.0.2:4444
2448 @item Example to listen and wait on port 4444 for connection
2449 -serial tcp::4444,server
2450 @item Example to not wait and listen on ip 192.168.0.100 port 4444
2451 -serial tcp:192.168.0.100:4444,server,nowait
2454 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
2455 The telnet protocol is used instead of raw tcp sockets. The options
2456 work the same as if you had specified @code{-serial tcp}. The
2457 difference is that the port acts like a telnet server or client using
2458 telnet option negotiation. This will also allow you to send the
2459 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
2460 sequence. Typically in unix telnet you do it with Control-] and then
2461 type "send break" followed by pressing the enter key.
2463 @item unix:@var{path}[,server][,nowait]
2464 A unix domain socket is used instead of a tcp socket. The option works the
2465 same as if you had specified @code{-serial tcp} except the unix domain socket
2466 @var{path} is used for connections.
2468 @item mon:@var{dev_string}
2469 This is a special option to allow the monitor to be multiplexed onto
2470 another serial port. The monitor is accessed with key sequence of
2471 @key{Control-a} and then pressing @key{c}. See monitor access
2472 @ref{pcsys_keys} in the -nographic section for more keys.
2473 @var{dev_string} should be any one of the serial devices specified
2474 above. An example to multiplex the monitor onto a telnet server
2475 listening on port 4444 would be:
2477 @item -serial mon:telnet::4444,server,nowait
2481 Braille device. This will use BrlAPI to display the braille output on a real
2485 Three button serial mouse. Configure the guest to use Microsoft protocol.
2489 DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
2490 "-parallel dev redirect the parallel port to char device 'dev
'\n",
2493 @item -parallel @var{dev}
2495 Redirect the virtual parallel port to host device @var{dev} (same
2496 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
2497 be used to use hardware devices connected on the corresponding host
2500 This option can be used several times to simulate up to 3 parallel
2503 Use @code{-parallel none} to disable all parallel ports.
2506 DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
2507 "-monitor dev redirect the monitor to char device 'dev
'\n",
2510 @item -monitor @var{dev}
2512 Redirect the monitor to host device @var{dev} (same devices as the
2514 The default device is @code{vc} in graphical mode and @code{stdio} in
2517 DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
2518 "-qmp dev like -monitor but opens in 'control
' mode\n",
2521 @item -qmp @var{dev}
2523 Like -monitor but opens in 'control
' mode.
2526 DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
2527 "-mon chardev=[name][,mode=readline|control][,default]\n", QEMU_ARCH_ALL)
2529 @item -mon chardev=[name][,mode=readline|control][,default]
2531 Setup monitor on chardev @var{name}.
2534 DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
2535 "-debugcon dev redirect the debug console to char device 'dev
'\n",
2538 @item -debugcon @var{dev}
2540 Redirect the debug console to host device @var{dev} (same devices as the
2541 serial port). The debug console is an I/O port which is typically port
2542 0xe9; writing to that I/O port sends output to this device.
2543 The default device is @code{vc} in graphical mode and @code{stdio} in
2547 DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
2548 "-pidfile file write PID to 'file
'\n", QEMU_ARCH_ALL)
2550 @item -pidfile @var{file}
2552 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
2556 DEF("singlestep", 0, QEMU_OPTION_singlestep, \
2557 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL)
2561 Run the emulation in single step mode.
2564 DEF("S", 0, QEMU_OPTION_S, \
2565 "-S freeze CPU at startup (use 'c
' to start execution)\n",
2570 Do not start CPU at startup (you must type 'c
' in the monitor).
2573 DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
2574 "-gdb dev wait for gdb connection on 'dev
'\n", QEMU_ARCH_ALL)
2576 @item -gdb @var{dev}
2578 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
2579 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
2580 stdio are reasonable use case. The latter is allowing to start QEMU from
2581 within gdb and establish the connection via a pipe:
2583 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
2587 DEF("s", 0, QEMU_OPTION_s, \
2588 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
2593 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
2594 (@pxref{gdb_usage}).
2597 DEF("d", HAS_ARG, QEMU_OPTION_d, \
2598 "-d item1,... enable logging of specified items (use '-d help
' for a list of log items)\n",
2601 @item -d @var{item1}[,...]
2603 Enable logging of specified items. Use '-d help
' for a list of log items.
2606 DEF("D", HAS_ARG, QEMU_OPTION_D, \
2607 "-D logfile output log to logfile (default stderr)\n",
2610 @item -D @var{logfile}
2612 Output log in @var{logfile} instead of to stderr
2615 DEF("L", HAS_ARG, QEMU_OPTION_L, \
2616 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
2621 Set the directory for the BIOS, VGA BIOS and keymaps.
2624 DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
2625 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL)
2627 @item -bios @var{file}
2629 Set the filename for the BIOS.
2632 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
2633 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL)
2637 Enable KVM full virtualization support. This option is only available
2638 if KVM support is enabled when compiling.
2641 DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
2642 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL)
2643 DEF("xen-create", 0, QEMU_OPTION_xen_create,
2644 "-xen-create create domain using xen hypercalls, bypassing xend\n"
2645 " warning: should not be used when xend is in use\n",
2647 DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
2648 "-xen-attach attach to existing xen domain\n"
2649 " xend will use this when starting QEMU\n",
2652 @item -xen-domid @var{id}
2654 Specify xen guest domain @var{id} (XEN only).
2657 Create domain using xen hypercalls, bypassing xend.
2658 Warning: should not be used when xend is in use (XEN only).
2661 Attach to existing xen domain.
2662 xend will use this when starting QEMU (XEN only).
2665 DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
2666 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL)
2670 Exit instead of rebooting.
2673 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
2674 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL)
2677 @findex -no-shutdown
2678 Don't exit QEMU on guest shutdown
, but instead only stop the emulation
.
2679 This allows
for instance switching to monitor to commit changes to the
2683 DEF("loadvm", HAS_ARG
, QEMU_OPTION_loadvm
, \
2684 "-loadvm [tag|id]\n" \
2685 " start right away with a saved state (loadvm in monitor)\n",
2688 @item
-loadvm @
var{file
}
2690 Start right away with a saved
state (@code
{loadvm
} in monitor
)
2694 DEF("daemonize", 0, QEMU_OPTION_daemonize
, \
2695 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL
)
2700 Daemonize the QEMU process after initialization
. QEMU will not detach from
2701 standard IO until it is ready to receive connections on any of its devices
.
2702 This option is a useful way
for external programs to launch QEMU without having
2703 to cope with initialization race conditions
.
2706 DEF("option-rom", HAS_ARG
, QEMU_OPTION_option_rom
, \
2707 "-option-rom rom load a file, rom, into the option ROM space\n",
2710 @item
-option
-rom @
var{file
}
2712 Load the contents of @
var{file
} as an option ROM
.
2713 This option is useful to load things like EtherBoot
.
2716 DEF("clock", HAS_ARG
, QEMU_OPTION_clock
, \
2717 "-clock force the use of the given methods for timer alarm.\n" \
2718 " To see what timers are available use '-clock help'\n",
2721 @item
-clock @
var{method
}
2723 Force the use of the given methods
for timer alarm
. To see what timers
2724 are available use @code
{-clock help
}.
2727 HXCOMM Options deprecated by
-rtc
2728 DEF("localtime", 0, QEMU_OPTION_localtime
, "", QEMU_ARCH_ALL
)
2729 DEF("startdate", HAS_ARG
, QEMU_OPTION_startdate
, "", QEMU_ARCH_ALL
)
2731 DEF("rtc", HAS_ARG
, QEMU_OPTION_rtc
, \
2732 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
2733 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
2738 @item
-rtc
[base
=utc|localtime|@
var{date
}][,clock
=host|vm
][,driftfix
=none|slew
]
2740 Specify @option
{base
} as @code
{utc
} or @code
{localtime
} to let the RTC start at the current
2741 UTC or local time
, respectively
. @code
{localtime
} is required
for correct date
in
2742 MS
-DOS or Windows
. To start at a specific point
in time
, provide @
var{date
} in the
2743 format @code
{2006-06-17T16
:01:21} or @code
{2006-06-17}. The
default base is UTC
.
2745 By
default the RTC is driven by the host system time
. This allows to use the
2746 RTC as accurate reference clock inside the guest
, specifically
if the host
2747 time is smoothly following an accurate external reference clock
, e
.g
. via NTP
.
2748 If you want to isolate the guest time from the host
, you can set @option
{clock
}
2749 to @code
{rt
} instead
. To even prevent it from progressing during suspension
,
2750 you can set it to @code
{vm
}.
2752 Enable @option
{driftfix
} (i386 targets only
) if you experience time drift problems
,
2753 specifically with Windows
' ACPI HAL. This option will try to figure out how
2754 many timer interrupts were not processed by the Windows guest and will
2758 DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
2759 "-icount [N|auto]\n" \
2760 " enable virtual instruction counter with 2^N clock ticks per\n" \
2761 " instruction\n", QEMU_ARCH_ALL)
2763 @item -icount [@var{N}|auto]
2765 Enable virtual instruction counter. The virtual cpu will execute one
2766 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
2767 then the virtual cpu speed will be automatically adjusted to keep virtual
2768 time within a few seconds of real time.
2770 Note that while this option can give deterministic behavior, it does not
2771 provide cycle accurate emulation. Modern CPUs contain superscalar out of
2772 order cores with complex cache hierarchies. The number of instructions
2773 executed often has little or no correlation with actual performance.
2776 DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
2777 "-watchdog i6300esb|ib700\n" \
2778 " enable virtual hardware watchdog [default=none]\n",
2781 @item -watchdog @var{model}
2783 Create a virtual hardware watchdog device. Once enabled (by a guest
2784 action), the watchdog must be periodically polled by an agent inside
2785 the guest or else the guest will be restarted.
2787 The @var{model} is the model of hardware watchdog to emulate. Choices
2788 for model are: @code{ib700} (iBASE 700) which is a very simple ISA
2789 watchdog with a single timer, or @code{i6300esb} (Intel 6300ESB I/O
2790 controller hub) which is a much more featureful PCI-based dual-timer
2791 watchdog. Choose a model for which your guest has drivers.
2793 Use @code{-watchdog help} to list available hardware models. Only one
2794 watchdog can be enabled for a guest.
2797 DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
2798 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
2799 " action when watchdog fires [default=reset]\n",
2802 @item -watchdog-action @var{action}
2803 @findex -watchdog-action
2805 The @var{action} controls what QEMU will do when the watchdog timer
2808 @code{reset} (forcefully reset the guest).
2809 Other possible actions are:
2810 @code{shutdown} (attempt to gracefully shutdown the guest),
2811 @code{poweroff} (forcefully poweroff the guest),
2812 @code{pause} (pause the guest),
2813 @code{debug} (print a debug message and continue), or
2814 @code{none} (do nothing).
2816 Note that the @code{shutdown} action requires that the guest responds
2817 to ACPI signals, which it may not be able to do in the sort of
2818 situations where the watchdog would have expired, and thus
2819 @code{-watchdog-action shutdown} is not recommended for production use.
2824 @item -watchdog i6300esb -watchdog-action pause
2825 @item -watchdog ib700
2829 DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
2830 "-echr chr set terminal escape character instead of ctrl-a\n",
2834 @item -echr @var{numeric_ascii_value}
2836 Change the escape character used for switching to the monitor when using
2837 monitor and serial sharing. The default is @code{0x01} when using the
2838 @code{-nographic} option. @code{0x01} is equal to pressing
2839 @code{Control-a}. You can select a different character from the ascii
2840 control keys where 1 through 26 map to Control-a through Control-z. For
2841 instance you could use the either of the following to change the escape
2842 character to Control-t.
2849 DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
2850 "-virtioconsole c\n" \
2851 " set virtio console\n", QEMU_ARCH_ALL)
2853 @item -virtioconsole @var{c}
2854 @findex -virtioconsole
2857 This option is maintained for backward compatibility.
2859 Please use @code{-device virtconsole} for the new way of invocation.
2862 DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
2863 "-show-cursor show cursor\n", QEMU_ARCH_ALL)
2866 @findex -show-cursor
2870 DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
2871 "-tb-size n set TB size\n", QEMU_ARCH_ALL)
2873 @item -tb-size @var{n}
2878 DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
2879 "-incoming p prepare for incoming migration, listen on port p\n",
2882 @item -incoming @var{port}
2884 Prepare for incoming migration, listen on @var{port}.
2887 DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
2888 "-nodefaults don't create
default devices
\n", QEMU_ARCH_ALL)
2892 Don't create default devices. Normally, QEMU sets the default devices like serial
2893 port, parallel port, virtual console, monitor device, VGA adapter, floppy and
2894 CD-ROM drive and others. The @code{-nodefaults} option will disable all those
2899 DEF("chroot
", HAS_ARG, QEMU_OPTION_chroot, \
2900 "-chroot dir chroot to dir just before starting the VM
\n",
2904 @item -chroot @var{dir}
2906 Immediately before starting guest execution, chroot to the specified
2907 directory. Especially useful in combination with -runas.
2911 DEF("runas
", HAS_ARG, QEMU_OPTION_runas, \
2912 "-runas user change to user id user just before starting the VM
\n",
2916 @item -runas @var{user}
2918 Immediately before starting guest execution, drop root privileges, switching
2919 to the specified user.
2922 DEF("prom
-env
", HAS_ARG, QEMU_OPTION_prom_env,
2923 "-prom
-env variable
=value
\n"
2924 " set OpenBIOS nvram variables
\n",
2925 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
2927 @item -prom-env @var{variable}=@var{value}
2929 Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
2931 DEF("semihosting
", 0, QEMU_OPTION_semihosting,
2932 "-semihosting semihosting mode
\n", QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA)
2935 @findex -semihosting
2936 Semihosting mode (ARM, M68K, Xtensa only).
2938 DEF("old
-param
", 0, QEMU_OPTION_old_param,
2939 "-old
-param old param mode
\n", QEMU_ARCH_ARM)
2942 @findex -old-param (ARM)
2943 Old param mode (ARM only).
2946 DEF("sandbox
", HAS_ARG, QEMU_OPTION_sandbox, \
2947 "-sandbox
<arg
> Enable seccomp mode
2 system call
filter (default 'off').\n",
2950 @item -sandbox @var{arg}
2952 Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
2953 disable it. The default is 'off'.
2956 DEF("readconfig
", HAS_ARG, QEMU_OPTION_readconfig,
2957 "-readconfig
<file
>\n", QEMU_ARCH_ALL)
2959 @item -readconfig @var{file}
2961 Read device configuration from @var{file}. This approach is useful when you want to spawn
2962 QEMU process with many command line options but you don't want to exceed the command line
2965 DEF("writeconfig
", HAS_ARG, QEMU_OPTION_writeconfig,
2966 "-writeconfig
<file
>\n"
2967 " read
/write config file
\n", QEMU_ARCH_ALL)
2969 @item -writeconfig @var{file}
2970 @findex -writeconfig
2971 Write device configuration to @var{file}. The @var{file} can be either filename to save
2972 command line and device configuration into file or dash @code{-}) character to print the
2973 output to stdout. This can be later used as input file for @code{-readconfig} option.
2975 DEF("nodefconfig
", 0, QEMU_OPTION_nodefconfig,
2977 " do not load
default config files at startup
\n",
2981 @findex -nodefconfig
2982 Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
2983 The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
2985 DEF("no
-user
-config
", 0, QEMU_OPTION_nouserconfig,
2987 " do not load user
-provided config files at startup
\n",
2990 @item -no-user-config
2991 @findex -no-user-config
2992 The @code{-no-user-config} option makes QEMU not load any of the user-provided
2993 config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config
2994 files from @var{datadir}.
2996 DEF("trace", HAS_ARG, QEMU_OPTION_trace,
2997 "-trace [events
=<file
>][,file
=<file
>]\n"
2998 " specify tracing options
\n",
3001 HXCOMM This line is not accurate, as some sub-options are backend-specific but
3002 HXCOMM HX does not support conditional compilation of text.
3003 @item -trace [events=@var{file}][,file=@var{file}]
3006 Specify tracing options.
3009 @item events=@var{file}
3010 Immediately enable events listed in @var{file}.
3011 The file must contain one event name (as listed in the @var{trace-events} file)
3013 This option is only available if QEMU has been compiled with
3014 either @var{simple} or @var{stderr} tracing backend.
3015 @item file=@var{file}
3016 Log output traces to @var{file}.
3018 This option is only available if QEMU has been compiled with
3019 the @var{simple} tracing backend.
3024 DEF("qtest
", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL)
3025 DEF("qtest
-log
", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL)
3028 DEF("enable
-fips
", 0, QEMU_OPTION_enablefips,
3029 "-enable
-fips enable FIPS
140-2 compliance
\n",
3034 @findex -enable-fips
3035 Enable FIPS 140-2 compliance mode.
3038 HXCOMM Deprecated by -machine accel=tcg property
3039 DEF("no
-kvm
", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386)
3041 HXCOMM Deprecated by kvm-pit driver properties
3042 DEF("no
-kvm
-pit
-reinjection
", 0, QEMU_OPTION_no_kvm_pit_reinjection,
3045 HXCOMM Deprecated (ignored)
3046 DEF("no
-kvm
-pit
", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386)
3048 HXCOMM Deprecated by -machine kernel_irqchip=on|off property
3049 DEF("no
-kvm
-irqchip
", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386)
3051 HXCOMM Deprecated (ignored)
3052 DEF("tdf
", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL)
3054 DEF("object
", HAS_ARG, QEMU_OPTION_object,
3055 "-object TYPENAME
[,PROP1
=VALUE1
,...]\n"
3056 " create an
new object of type TYPENAME setting properties
\n"
3057 " in the order they are specified
. Note that the
'id'\n"
3058 " property must be set
. These objects are placed
in the
\n"
3059 " '/objects' path
.\n",
3062 @item -object @var{typename}[,@var{prop1}=@var{value1},...]
3064 Create an new object of type @var{typename} setting properties
3065 in the order they are specified. Note that the 'id'
3066 property must be set. These objects are placed in the
3070 HXCOMM This is the last statement. Insert new options before this line!