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
]\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}]
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
196 # try to boot from network first, then from hard disk
197 qemu-system-i386 -boot order=nc
198 # boot from CD-ROM first, switch back to default order after reboot
199 qemu-system-i386 -boot once=d
200 # boot with a splash picture for 5 seconds.
201 qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
204 Note: The legacy format '-boot @
var{drives
}' is still supported but its
205 use is discouraged as it may be removed from future versions.
208 DEF("m", HAS_ARG, QEMU_OPTION_m,
209 "-m megs set virtual RAM size to megs MB [default="
210 stringify(DEFAULT_RAM_SIZE) "]\n", QEMU_ARCH_ALL)
214 Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally,
215 a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or
216 gigabytes respectively.
219 DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
220 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
222 @item -mem-path @var{path}
224 Allocate guest RAM from a temporarily created file in @var{path}.
228 DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
229 "-mem-prealloc preallocate guest memory (use with -mem-path)\n",
233 @findex -mem-prealloc
234 Preallocate memory when using -mem-path.
238 DEF("k", HAS_ARG, QEMU_OPTION_k,
239 "-k language use keyboard layout (for example 'fr
' for French)\n",
242 @item -k @var{language}
244 Use keyboard layout @var{language} (for example @code{fr} for
245 French). This option is only needed where it is not easy to get raw PC
246 keycodes (e.g. on Macs, with some X11 servers or with a VNC
247 display). You don't normally need to use it on PC
/Linux or PC
/Windows
250 The available layouts are
:
252 ar de
-ch es fo fr
-ca hu ja mk no pt
-br sv
253 da en
-gb et fr fr
-ch is lt nl pl ru th
254 de en
-us fi fr
-be hr it lv nl
-be pt sl tr
257 The
default is @code
{en
-us
}.
261 DEF("audio-help", 0, QEMU_OPTION_audio_help
,
262 "-audio-help print list of audio drivers and their options\n",
267 Will show the audio subsystem help
: list of drivers
, tunable
271 DEF("soundhw", HAS_ARG
, QEMU_OPTION_soundhw
,
272 "-soundhw c1,... enable audio support\n"
273 " and only specified sound cards (comma separated list)\n"
274 " use '-soundhw help' to get the list of supported cards\n"
275 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL
)
277 @item
-soundhw @
var{card1
}[,@
var{card2
},...] or
-soundhw all
279 Enable audio and selected sound hardware
. Use
'help' to print all
280 available sound hardware
.
283 qemu
-system
-i386
-soundhw sb16
,adlib disk
.img
284 qemu
-system
-i386
-soundhw es1370 disk
.img
285 qemu
-system
-i386
-soundhw ac97 disk
.img
286 qemu
-system
-i386
-soundhw hda disk
.img
287 qemu
-system
-i386
-soundhw all disk
.img
288 qemu
-system
-i386
-soundhw help
291 Note that Linux
's i810_audio OSS kernel (for AC97) module might
292 require manually specifying clocking.
295 modprobe i810_audio clocking=48000
299 DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
300 "-balloon none disable balloon device\n"
301 "-balloon virtio[,addr=str]\n"
302 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL)
306 Disable balloon device.
307 @item -balloon virtio[,addr=@var{addr}]
308 Enable virtio balloon device (default), optionally with PCI address
312 DEF("device", HAS_ARG, QEMU_OPTION_device,
313 "-device driver[,prop[=value][,...]]\n"
314 " add device (based on driver)\n"
315 " prop=value,... sets driver properties\n"
316 " use '-device help
' to print all possible drivers\n"
317 " use '-device driver
,help
' to print all possible properties\n",
320 @item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
322 Add device @var{driver}. @var{prop}=@var{value} sets driver
323 properties. Valid properties depend on the driver. To get help on
324 possible drivers and properties, use @code{-device help} and
325 @code{-device @var{driver},help}.
328 DEF("name", HAS_ARG, QEMU_OPTION_name,
329 "-name string1[,process=string2]\n"
330 " set the name of the guest\n"
331 " string1 sets the window title and string2 the process name (on Linux)\n",
334 @item -name @var{name}
336 Sets the @var{name} of the guest.
337 This name will be displayed in the SDL window caption.
338 The @var{name} will also be used for the VNC server.
339 Also optionally set the top visible process name in Linux.
342 DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
343 "-uuid %08x-%04x-%04x-%04x-%012x\n"
344 " specify machine UUID\n", QEMU_ARCH_ALL)
346 @item -uuid @var{uuid}
356 DEFHEADING(Block device options:)
361 DEF("fda", HAS_ARG, QEMU_OPTION_fda,
362 "-fda/-fdb file use 'file
' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
363 DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
365 @item -fda @var{file}
366 @item -fdb @var{file}
369 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can
370 use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}).
373 DEF("hda", HAS_ARG, QEMU_OPTION_hda,
374 "-hda/-hdb file use 'file
' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
375 DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
376 DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
377 "-hdc/-hdd file use 'file
' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
378 DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
380 @item -hda @var{file}
381 @item -hdb @var{file}
382 @item -hdc @var{file}
383 @item -hdd @var{file}
388 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
391 DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
392 "-cdrom file use 'file
' as IDE cdrom image (cdrom is ide1 master)\n",
395 @item -cdrom @var{file}
397 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
398 @option{-cdrom} at the same time). You can use the host CD-ROM by
399 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
402 DEF("drive", HAS_ARG, QEMU_OPTION_drive,
403 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
404 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
405 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
406 " [,serial=s][,addr=A][,id=name][,aio=threads|native]\n"
407 " [,readonly=on|off][,copy-on-read=on|off]\n"
408 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]][[,iops=i]|[[,iops_rd=r][,iops_wr=w]]\n"
409 " use 'file
' as a drive image\n", QEMU_ARCH_ALL)
411 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
414 Define a new drive. Valid options are:
417 @item file=@var{file}
418 This option defines which disk image (@pxref{disk_images}) to use with
419 this drive. If the filename contains comma, you must double it
420 (for instance, "file=my,,file" to use file "my,file").
422 Special files such as iSCSI devices can be specified using protocol
423 specific URLs. See the section for "Device URL Syntax" for more information.
424 @item if=@var{interface}
425 This option defines on which type on interface the drive is connected.
426 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio.
427 @item bus=@var{bus},unit=@var{unit}
428 These options define where is connected the drive by defining the bus number and
430 @item index=@var{index}
431 This option defines where is connected the drive by using an index in the list
432 of available connectors of a given interface type.
433 @item media=@var{media}
434 This option defines the type of the media: disk or cdrom.
435 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
436 These options have the same definition as they have in @option{-hdachs}.
437 @item snapshot=@var{snapshot}
438 @var{snapshot} is "on" or "off" and allows to enable snapshot for given drive (see @option{-snapshot}).
439 @item cache=@var{cache}
440 @var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data.
442 @var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
443 @item discard=@var{discard}
444 @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.
445 @item format=@var{format}
446 Specify which disk @var{format} will be used rather than detecting
447 the format. Can be used to specifiy format=raw to avoid interpreting
448 an untrusted format header.
449 @item serial=@var{serial}
450 This option specifies the serial number to assign to the device.
451 @item addr=@var{addr}
452 Specify the controller's PCI
address (if=virtio only
).
453 @item werror
=@
var{action
},rerror
=@
var{action
}
454 Specify which @
var{action
} to take on write and read errors
. Valid actions are
:
455 "ignore" (ignore the error and
try to
continue), "stop" (pause QEMU
),
456 "report" (report the error to the guest
), "enospc" (pause QEMU only
if the
457 host disk is full
; report the error to the guest otherwise
).
458 The
default setting is @option
{werror
=enospc
} and @option
{rerror
=report
}.
460 Open drive @option
{file
} as read
-only
. Guest write attempts will fail
.
461 @item copy
-on
-read
=@
var{copy
-on
-read
}
462 @
var{copy
-on
-read
} is
"on" or
"off" and enables whether to copy read backing
463 file sectors into the image file
.
466 By
default, the @option
{cache
=writeback
} mode is used
. It will report data
467 writes as completed as soon as the data is present
in the host page cache
.
468 This is safe as long as your guest OS makes sure to correctly flush disk caches
469 where needed
. If your guest OS does not handle volatile disk write caches
470 correctly and your host crashes or loses power
, then the guest may experience
473 For such guests
, you should consider
using @option
{cache
=writethrough
}. This
474 means that the host page cache will be used to read and write data
, but write
475 notification will be sent to the guest only after QEMU has made sure to flush
476 each write to the disk
. Be aware that
this has a major impact on performance
.
478 The host page cache can be avoided entirely with @option
{cache
=none
}. This will
479 attempt to
do disk IO directly to the guest
's memory. QEMU may still perform
480 an internal copy of the data. Note that this is considered a writeback mode and
481 the guest OS must handle the disk write cache correctly in order to avoid data
482 corruption on host crashes.
484 The host page cache can be avoided while only sending write notifications to
485 the guest when the data has been flushed to the disk using
486 @option{cache=directsync}.
488 In case you don't care about data integrity over host failures
, use
489 @option
{cache
=unsafe
}. This option tells QEMU that it
never needs to write any
490 data to the disk but can instead keep things
in cache
. If anything goes wrong
,
491 like your host losing power
, the disk storage getting disconnected accidentally
,
492 etc
. your image will most probably be rendered unusable
. When
using
493 the @option
{-snapshot
} option
, unsafe caching is always used
.
495 Copy
-on
-read avoids accessing the same backing file sectors repeatedly and is
496 useful when the backing file is over a slow network
. By
default copy
-on
-read
499 Instead of @option
{-cdrom
} you can use
:
501 qemu
-system
-i386
-drive file
=file
,index
=2,media
=cdrom
504 Instead of @option
{-hda
}, @option
{-hdb
}, @option
{-hdc
}, @option
{-hdd
}, you can
507 qemu
-system
-i386
-drive file
=file
,index
=0,media
=disk
508 qemu
-system
-i386
-drive file
=file
,index
=1,media
=disk
509 qemu
-system
-i386
-drive file
=file
,index
=2,media
=disk
510 qemu
-system
-i386
-drive file
=file
,index
=3,media
=disk
513 You can open an image
using pre
-opened file descriptors from an fd set
:
516 -add
-fd fd
=3,set
=2,opaque
="rdwr:/path/to/file"
517 -add
-fd fd
=4,set
=2,opaque
="rdonly:/path/to/file"
518 -drive file
=/dev
/fdset
/2,index
=0,media
=disk
521 You can connect a CDROM to the slave of ide0
:
523 qemu
-system
-i386
-drive file
=file
,if=ide
,index
=1,media
=cdrom
526 If you don
't specify the "file=" argument, you define an empty drive:
528 qemu-system-i386 -drive if=ide,index=1,media=cdrom
531 You can connect a SCSI disk with unit ID 6 on the bus #0:
533 qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6
536 Instead of @option{-fda}, @option{-fdb}, you can use:
538 qemu-system-i386 -drive file=file,index=0,if=floppy
539 qemu-system-i386 -drive file=file,index=1,if=floppy
542 By default, @var{interface} is "ide" and @var{index} is automatically
545 qemu-system-i386 -drive file=a -drive file=b"
549 qemu-system-i386 -hda a -hdb b
553 DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
554 "-mtdblock file use 'file
' as on-board Flash memory image\n",
557 @item -mtdblock @var{file}
559 Use @var{file} as on-board Flash memory image.
562 DEF("sd", HAS_ARG, QEMU_OPTION_sd,
563 "-sd file use 'file
' as SecureDigital card image\n", QEMU_ARCH_ALL)
567 Use @var{file} as SecureDigital card image.
570 DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
571 "-pflash file use 'file
' as a parallel flash image\n", QEMU_ARCH_ALL)
573 @item -pflash @var{file}
575 Use @var{file} as a parallel flash image.
578 DEF("snapshot", 0, QEMU_OPTION_snapshot,
579 "-snapshot write to temporary files instead of disk image files\n",
584 Write to temporary files instead of disk image files. In this case,
585 the raw disk image you use is not written back. You can however force
586 the write back by pressing @key{C-a s} (@pxref{disk_images}).
589 DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
590 "-hdachs c,h,s[,t]\n" \
591 " force hard disk 0 physical geometry and the optional BIOS\n" \
592 " translation (t=none or lba) (usually QEMU can guess them)\n",
595 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
597 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
598 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
599 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
600 all those parameters. This option is useful for old MS-DOS disk
604 DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
605 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
606 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
611 @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}]
613 Define a new file system device. Valid options are:
616 This option specifies the fs driver backend to use.
617 Currently "local", "handle" and "proxy" file system drivers are supported.
619 Specifies identifier for this device
620 @item path=@var{path}
621 Specifies the export path for the file system device. Files under
622 this path will be available to the 9p client on the guest.
623 @item security_model=@var{security_model}
624 Specifies the security model to be used for this export path.
625 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
626 In "passthrough" security model, files are stored using the same
627 credentials as they are created on the guest. This requires QEMU
628 to run as root. In "mapped-xattr" security model, some of the file
629 attributes like uid, gid, mode bits and link target are stored as
630 file attributes. For "mapped-file" these attributes are stored in the
631 hidden .virtfs_metadata directory. Directories exported by this security model cannot
632 interact with other unix tools. "none" security model is same as
633 passthrough except the sever won't report failures
if it fails to
634 set file attributes like ownership
. Security model is mandatory
635 only
for local fsdriver
. Other
fsdrivers (like handle
, proxy
) don
't take
636 security model as a parameter.
637 @item writeout=@var{writeout}
638 This is an optional argument. The only supported value is "immediate".
639 This means that host page cache will be used to read and write data but
640 write notification will be sent to the guest only when the data has been
641 reported as written by the storage subsystem.
643 Enables exporting 9p share as a readonly mount for guests. By default
644 read-write access is given.
645 @item socket=@var{socket}
646 Enables proxy filesystem driver to use passed socket file for communicating
647 with virtfs-proxy-helper
648 @item sock_fd=@var{sock_fd}
649 Enables proxy filesystem driver to use passed socket descriptor for
650 communicating with virtfs-proxy-helper. Usually a helper like libvirt
651 will create socketpair and pass one of the fds as sock_fd
654 -fsdev option is used along with -device driver "virtio-9p-pci".
655 @item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
656 Options for virtio-9p-pci driver are:
659 Specifies the id value specified along with -fsdev option
660 @item mount_tag=@var{mount_tag}
661 Specifies the tag name to be used by the guest to mount this export point
666 DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
667 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
668 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
673 @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}]
676 The general form of a Virtual File system pass-through options are:
679 This option specifies the fs driver backend to use.
680 Currently "local", "handle" and "proxy" file system drivers are supported.
682 Specifies identifier for this device
683 @item path=@var{path}
684 Specifies the export path for the file system device. Files under
685 this path will be available to the 9p client on the guest.
686 @item security_model=@var{security_model}
687 Specifies the security model to be used for this export path.
688 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
689 In "passthrough" security model, files are stored using the same
690 credentials as they are created on the guest. This requires QEMU
691 to run as root. In "mapped-xattr" security model, some of the file
692 attributes like uid, gid, mode bits and link target are stored as
693 file attributes. For "mapped-file" these attributes are stored in the
694 hidden .virtfs_metadata directory. Directories exported by this security model cannot
695 interact with other unix tools. "none" security model is same as
696 passthrough except the sever won't report failures
if it fails to
697 set file attributes like ownership
. Security model is mandatory only
698 for local fsdriver
. Other
fsdrivers (like handle
, proxy
) don
't take security
699 model as a parameter.
700 @item writeout=@var{writeout}
701 This is an optional argument. The only supported value is "immediate".
702 This means that host page cache will be used to read and write data but
703 write notification will be sent to the guest only when the data has been
704 reported as written by the storage subsystem.
706 Enables exporting 9p share as a readonly mount for guests. By default
707 read-write access is given.
708 @item socket=@var{socket}
709 Enables proxy filesystem driver to use passed socket file for
710 communicating with virtfs-proxy-helper. Usually a helper like libvirt
711 will create socketpair and pass one of the fds as sock_fd
713 Enables proxy filesystem driver to use passed 'sock_fd
' as the socket
714 descriptor for interfacing with virtfs-proxy-helper
718 DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
719 "-virtfs_synth Create synthetic file system image\n",
723 @findex -virtfs_synth
724 Create synthetic file system image
732 DEFHEADING(USB options:)
737 DEF("usb", 0, QEMU_OPTION_usb,
738 "-usb enable the USB driver (will be the default soon)\n",
743 Enable the USB driver (will be the default soon)
746 DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
747 "-usbdevice name add the host or guest USB device 'name
'\n",
751 @item -usbdevice @var{devname}
753 Add the USB device @var{devname}. @xref{usb_devices}.
758 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
761 Pointer device that uses absolute coordinates (like a touchscreen). This
762 means QEMU is able to report the mouse position without having to grab the
763 mouse. Also overrides the PS/2 mouse emulation when activated.
765 @item disk:[format=@var{format}]:@var{file}
766 Mass storage device based on file. The optional @var{format} argument
767 will be used rather than detecting the format. Can be used to specifiy
768 @code{format=raw} to avoid interpreting an untrusted format header.
770 @item host:@var{bus}.@var{addr}
771 Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
773 @item host:@var{vendor_id}:@var{product_id}
774 Pass through the host device identified by @var{vendor_id}:@var{product_id}
777 @item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
778 Serial converter to host character device @var{dev}, see @code{-serial} for the
782 Braille device. This will use BrlAPI to display the braille output on a real
785 @item net:@var{options}
786 Network adapter that supports CDC ethernet and RNDIS protocols.
796 DEFHEADING(Display options:)
801 DEF("display", HAS_ARG, QEMU_OPTION_display,
802 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
803 " [,window_close=on|off]|curses|none|\n"
804 " vnc=<display>[,<optargs>]\n"
805 " select display type\n", QEMU_ARCH_ALL)
807 @item -display @var{type}
809 Select type of display to use. This option is a replacement for the
810 old style -sdl/-curses/... options. Valid values for @var{type} are
813 Display video output via SDL (usually in a separate graphics
814 window; see the SDL documentation for other possibilities).
816 Display video output via curses. For graphics device models which
817 support a text mode, QEMU can display this output using a
818 curses/ncurses interface. Nothing is displayed when the graphics
819 device is in graphical mode or if the graphics device does not support
820 a text mode. Generally only the VGA device models support text mode.
822 Do not display video output. The guest will still see an emulated
823 graphics card, but its output will not be displayed to the QEMU
824 user. This option differs from the -nographic option in that it
825 only affects what is done with video output; -nographic also changes
826 the destination of the serial and parallel port data.
828 Start a VNC server on display <arg>
832 DEF("nographic", 0, QEMU_OPTION_nographic,
833 "-nographic disable graphical output and redirect serial I/Os to console\n",
838 Normally, QEMU uses SDL to display the VGA output. With this option,
839 you can totally disable graphical output so that QEMU is a simple
840 command line application. The emulated serial port is redirected on
841 the console. Therefore, you can still use QEMU to debug a Linux kernel
842 with a serial console.
845 DEF("curses", 0, QEMU_OPTION_curses,
846 "-curses use a curses/ncurses interface instead of SDL\n",
851 Normally, QEMU uses SDL to display the VGA output. With this option,
852 QEMU can display the VGA output when in text mode using a
853 curses/ncurses interface. Nothing is displayed in graphical mode.
856 DEF("no-frame", 0, QEMU_OPTION_no_frame,
857 "-no-frame open SDL window without a frame and window decorations\n",
862 Do not use decorations for SDL windows and start them using the whole
863 available screen space. This makes the using QEMU in a dedicated desktop
864 workspace more convenient.
867 DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
868 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
873 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
874 affects the special keys (for fullscreen, monitor-mode switching, etc).
877 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
878 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
883 Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
884 affects the special keys (for fullscreen, monitor-mode switching, etc).
887 DEF("no-quit", 0, QEMU_OPTION_no_quit,
888 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL)
892 Disable SDL window close capability.
895 DEF("sdl", 0, QEMU_OPTION_sdl,
896 "-sdl enable SDL\n", QEMU_ARCH_ALL)
903 DEF("spice", HAS_ARG, QEMU_OPTION_spice,
904 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
905 " [,x509-key-file=<file>][,x509-key-password=<file>]\n"
906 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
907 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6]\n"
908 " [,tls-ciphers=<list>]\n"
909 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
910 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
911 " [,sasl][,password=<secret>][,disable-ticketing]\n"
912 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
913 " [,jpeg-wan-compression=[auto|never|always]]\n"
914 " [,zlib-glz-wan-compression=[auto|never|always]]\n"
915 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
916 " [,agent-mouse=[on|off]][,playback-compression=[on|off]]\n"
917 " [,seamless-migration=[on|off]]\n"
919 " at least one of {port, tls-port} is mandatory\n",
922 @item -spice @var{option}[,@var{option}[,...]]
924 Enable the spice remote desktop protocol. Valid options are
929 Set the TCP port spice is listening on for plaintext channels.
932 Set the IP address spice is listening on. Default is any address.
936 Force using the specified IP version.
938 @item password=<secret>
939 Set the password you need to authenticate.
942 Require that the client use SASL to authenticate with the spice.
943 The exact choice of authentication method used is controlled from the
944 system / user's SASL configuration file
for the
'qemu' service
. This
945 is typically found
in /etc
/sasl2
/qemu
.conf
. If running QEMU as an
946 unprivileged user
, an environment variable SASL_CONF_PATH can be used
947 to make it search alternate locations
for the service config
.
948 While some SASL auth methods can also provide data
encryption (eg GSSAPI
),
949 it is recommended that SASL always be combined with the
'tls' and
950 'x509' settings to enable use of SSL and server certificates
. This
951 ensures a data encryption preventing compromise of authentication
954 @item disable
-ticketing
955 Allow client connects without authentication
.
957 @item disable
-copy
-paste
958 Disable copy paste between the client and the guest
.
961 Set the TCP port spice is listening on
for encrypted channels
.
964 Set the x509 file directory
. Expects same filenames as
-vnc $display
,x509
=$dir
966 @item x509
-key
-file
=<file
>
967 @item x509
-key
-password
=<file
>
968 @item x509
-cert
-file
=<file
>
969 @item x509
-cacert
-file
=<file
>
970 @item x509
-dh
-key
-file
=<file
>
971 The x509 file names can also be configured individually
.
973 @item tls
-ciphers
=<list
>
974 Specify which ciphers to use
.
976 @item tls
-channel
=[main|display|cursor|inputs|record|playback
]
977 @item plaintext
-channel
=[main|display|cursor|inputs|record|playback
]
978 Force specific channel to be used with or without TLS encryption
. The
979 options can be specified multiple times to configure multiple
980 channels
. The special name
"default" can be used to set the
default
981 mode
. For channels which are not explicitly forced into one mode the
982 spice client is allowed to pick tls
/plaintext as he pleases
.
984 @item image
-compression
=[auto_glz|auto_lz|quic|glz|lz|off
]
985 Configure image
compression (lossless
).
988 @item jpeg
-wan
-compression
=[auto|
never|always
]
989 @item zlib
-glz
-wan
-compression
=[auto|
never|always
]
990 Configure wan image
compression (lossy
for slow links
).
993 @item streaming
-video
=[off|all|filter
]
994 Configure video stream detection
. Default is filter
.
996 @item agent
-mouse
=[on|off
]
997 Enable
/disable passing mouse events via vdagent
. Default is on
.
999 @item playback
-compression
=[on|off
]
1000 Enable
/disable audio stream
compression (using celt
0.5.1). Default is on
.
1002 @item seamless
-migration
=[on|off
]
1003 Enable
/disable spice seamless migration
. Default is off
.
1008 DEF("portrait", 0, QEMU_OPTION_portrait
,
1009 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
1014 Rotate graphical output
90 deg
left (only PXA LCD
).
1017 DEF("rotate", HAS_ARG
, QEMU_OPTION_rotate
,
1018 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
1021 @item
-rotate @
var{deg
}
1023 Rotate graphical output some deg
left (only PXA LCD
).
1026 DEF("vga", HAS_ARG
, QEMU_OPTION_vga
,
1027 "-vga [std|cirrus|vmware|qxl|xenfb|none]\n"
1028 " select video card type\n", QEMU_ARCH_ALL
)
1030 @item
-vga @
var{type
}
1032 Select type of VGA card to emulate
. Valid values
for @
var{type
} are
1035 Cirrus Logic GD5446 Video card
. All Windows versions starting from
1036 Windows
95 should recognize and use
this graphic card
. For optimal
1037 performances
, use
16 bit color depth
in the guest and the host OS
.
1038 (This one is the
default)
1040 Standard VGA card with Bochs VBE extensions
. If your guest OS
1041 supports the VESA
2.0 VBE
extensions (e
.g
. Windows XP
) and
if you want
1042 to use high resolution
modes (>= 1280x1024x16
) then you should use
1045 VMWare SVGA
-II compatible adapter
. Use it
if you have sufficiently
1046 recent XFree86
/XOrg server or Windows guest with a driver
for this
1049 QXL paravirtual graphic card
. It is VGA
compatible (including VESA
1050 2.0 VBE support
). Works best with qxl guest drivers installed though
.
1051 Recommended choice when
using the spice protocol
.
1057 DEF("full-screen", 0, QEMU_OPTION_full_screen
,
1058 "-full-screen start in full screen\n", QEMU_ARCH_ALL
)
1061 @findex
-full
-screen
1062 Start
in full screen
.
1065 DEF("g", 1, QEMU_OPTION_g
,
1066 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
1067 QEMU_ARCH_PPC | QEMU_ARCH_SPARC
)
1069 @item
-g @
var{width
}x@
var{height
}[x@
var{depth
}]
1071 Set the initial graphical resolution and
depth (PPC
, SPARC only
).
1074 DEF("vnc", HAS_ARG
, QEMU_OPTION_vnc
,
1075 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL
)
1077 @item
-vnc @
var{display
}[,@
var{option
}[,@
var{option
}[,...]]]
1079 Normally
, QEMU uses SDL to display the VGA output
. With
this option
,
1080 you can have QEMU listen on VNC display @
var{display
} and redirect the VGA
1081 display over the VNC session
. It is very useful to enable the usb
1082 tablet device when
using this option (option @option
{-usbdevice
1083 tablet
}). When
using the VNC display
, you must use the @option
{-k
}
1084 parameter to set the keyboard layout
if you are not
using en
-us
. Valid
1085 syntax
for the @
var{display
} is
1089 @item @
var{host
}:@
var{d
}
1091 TCP connections will only be allowed from @
var{host
} on display @
var{d
}.
1092 By convention the TCP port is
5900+@
var{d
}. Optionally
, @
var{host
} can
1093 be omitted
in which
case the server will accept connections from any host
.
1095 @item unix
:@
var{path
}
1097 Connections will be allowed over UNIX domain sockets where @
var{path
} is the
1098 location of a unix socket to listen
for connections on
.
1102 VNC is initialized but not started
. The monitor @code
{change
} command
1103 can be used to later start the VNC server
.
1107 Following the @
var{display
} value there may be one or more @
var{option
} flags
1108 separated by commas
. Valid options are
1114 Connect to a listening VNC client via a ``reverse
'' connection
. The
1115 client is specified by the @
var{display
}. For reverse network
1116 connections (@
var{host
}:@
var{d
},@code
{reverse
}), the @
var{d
} argument
1117 is a TCP port number
, not a display number
.
1121 Opens an additional TCP listening port dedicated to VNC Websocket connections
.
1122 By defintion the Websocket port is
5700+@
var{display
}. If @
var{host
} is
1123 specified connections will only be allowed from
this host
.
1124 As an alternative the Websocket port could be specified by
using
1125 @code
{websocket
}=@
var{port
}.
1129 Require that password based authentication is used
for client connections
.
1131 The password must be set separately
using the @code
{set_password
} command
in
1132 the @ref
{pcsys_monitor
}. The syntax to change your password is
:
1133 @code
{set_password
<protocol
> <password
>} where
<protocol
> could be either
1136 If you would like to change
<protocol
> password expiration
, you should use
1137 @code
{expire_password
<protocol
> <expiration
-time
>} where expiration time could
1138 be one of the following options
: now
, never, +seconds or UNIX time of
1139 expiration
, e
.g
. +60 to make password expire
in 60 seconds
, or
1335196800
1140 to make password expire on
"Mon Apr 23 12:00:00 EDT 2012" (UNIX time
for this
1143 You can also use keywords
"now" or
"never" for the expiration time to
1144 allow
<protocol
> password to expire immediately or
never expire
.
1148 Require that client use TLS when communicating with the VNC server
. This
1149 uses anonymous TLS credentials so is susceptible to a man
-in-the
-middle
1150 attack
. It is recommended that
this option be combined with either the
1151 @option
{x509
} or @option
{x509verify
} options
.
1153 @item x509
=@
var{/path
/to
/certificate
/dir
}
1155 Valid
if @option
{tls
} is specified
. Require that x509 credentials are used
1156 for negotiating the TLS session
. The server will send its x509 certificate
1157 to the client
. It is recommended that a password be set on the VNC server
1158 to provide authentication of the client when
this is used
. The path following
1159 this option specifies where the x509 certificates are to be loaded from
.
1160 See the @ref
{vnc_security
} section
for details on generating certificates
.
1162 @item x509verify
=@
var{/path
/to
/certificate
/dir
}
1164 Valid
if @option
{tls
} is specified
. Require that x509 credentials are used
1165 for negotiating the TLS session
. The server will send its x509 certificate
1166 to the client
, and request that the client send its own x509 certificate
.
1167 The server will validate the client
's certificate against the CA certificate,
1168 and reject clients when validation fails. If the certificate authority is
1169 trusted, this is a sufficient authentication mechanism. You may still wish
1170 to set a password on the VNC server as a second authentication layer. The
1171 path following this option specifies where the x509 certificates are to
1172 be loaded from. See the @ref{vnc_security} section for details on generating
1177 Require that the client use SASL to authenticate with the VNC server.
1178 The exact choice of authentication method used is controlled from the
1179 system / user's SASL configuration file
for the
'qemu' service
. This
1180 is typically found
in /etc
/sasl2
/qemu
.conf
. If running QEMU as an
1181 unprivileged user
, an environment variable SASL_CONF_PATH can be used
1182 to make it search alternate locations
for the service config
.
1183 While some SASL auth methods can also provide data
encryption (eg GSSAPI
),
1184 it is recommended that SASL always be combined with the
'tls' and
1185 'x509' settings to enable use of SSL and server certificates
. This
1186 ensures a data encryption preventing compromise of authentication
1187 credentials
. See the @ref
{vnc_security
} section
for details on
using
1188 SASL authentication
.
1192 Turn on access control lists
for checking of the x509 client certificate
1193 and SASL party
. For x509 certs
, the ACL check is made against the
1194 certificate
's distinguished name. This is something that looks like
1195 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1196 made against the username, which depending on the SASL plugin, may
1197 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1198 When the @option{acl} flag is set, the initial access list will be
1199 empty, with a @code{deny} policy. Thus no one will be allowed to
1200 use the VNC server until the ACLs have been loaded. This can be
1201 achieved using the @code{acl} monitor command.
1205 Enable lossy compression methods (gradient, JPEG, ...). If this
1206 option is set, VNC client may receive lossy framebuffer updates
1207 depending on its encoding settings. Enabling this option can save
1208 a lot of bandwidth at the expense of quality.
1212 Disable adaptive encodings. Adaptive encodings are enabled by default.
1213 An adaptive encoding will try to detect frequently updated screen regions,
1214 and send updates in these regions using a lossy encoding (like JPEG).
1215 This can be really helpful to save bandwidth when playing videos. Disabling
1216 adaptive encodings allows to restore the original static behavior of encodings
1219 @item share=[allow-exclusive|force-shared|ignore]
1221 Set display sharing policy. 'allow
-exclusive
' allows clients to ask
1222 for exclusive access. As suggested by the rfb spec this is
1223 implemented by dropping other connections. Connecting multiple
1224 clients in parallel requires all clients asking for a shared session
1225 (vncviewer: -shared switch). This is the default. 'force
-shared
'
1226 disables exclusive client access. Useful for shared desktop sessions,
1227 where you don't want someone forgetting specify
-shared disconnect
1228 everybody
else. 'ignore' completely ignores the shared flag and
1229 allows everybody connect unconditionally
. Doesn
't conform to the rfb
1230 spec but is traditional QEMU behavior.
1238 ARCHHEADING(, QEMU_ARCH_I386)
1240 ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1245 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1246 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1251 Use it when installing Windows 2000 to avoid a disk full bug. After
1252 Windows 2000 is installed, you no longer need this option (this option
1253 slows down the IDE transfers).
1256 HXCOMM Deprecated by -rtc
1257 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1259 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1260 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1263 @item -no-fd-bootchk
1264 @findex -no-fd-bootchk
1265 Disable boot signature checking for floppy disks in Bochs BIOS. It may
1266 be needed to boot from old floppy disks.
1267 TODO: check reference to Bochs BIOS.
1270 DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1271 "-no-acpi disable ACPI\n", QEMU_ARCH_I386)
1275 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1276 it if your guest OS complains about ACPI problems (PC target machine
1280 DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1281 "-no-hpet disable HPET\n", QEMU_ARCH_I386)
1285 Disable HPET support.
1288 DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1289 "-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"
1290 " ACPI table description\n", QEMU_ARCH_I386)
1292 @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}]...]
1294 Add ACPI table with specified header fields and context from specified files.
1295 For file=, take whole ACPI table from the specified files, including all
1296 ACPI headers (possible overridden by other options).
1297 For data=, only data
1298 portion of the table is used, all header information is specified in the
1302 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1303 "-smbios file=binary\n"
1304 " load SMBIOS entry from binary file\n"
1305 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1306 " specify SMBIOS type 0 fields\n"
1307 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1308 " [,uuid=uuid][,sku=str][,family=str]\n"
1309 " specify SMBIOS type 1 fields\n", QEMU_ARCH_I386)
1311 @item -smbios file=@var{binary}
1313 Load SMBIOS entry from binary file.
1315 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}]
1316 Specify SMBIOS type 0 fields
1318 @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}]
1319 Specify SMBIOS type 1 fields
1327 DEFHEADING(Network options:)
1332 HXCOMM Legacy slirp options (now moved to -net user):
1334 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1335 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1336 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1338 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1342 DEF("net", HAS_ARG, QEMU_OPTION_net,
1343 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
1344 " create a new Network Interface Card and connect it to VLAN 'n
'\n"
1346 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=on|off]\n"
1347 " [,hostname=host][,dhcpstart=addr][,dns=addr][,dnssearch=domain][,tftp=dir]\n"
1348 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1350 "[,smb=dir[,smbserver=addr]]\n"
1352 " connect the user mode network stack to VLAN 'n
', configure its\n"
1353 " DHCP server and enabled optional services\n"
1356 "-net tap[,vlan=n][,name=str],ifname=name\n"
1357 " connect the host TAP network interface to VLAN 'n
'\n"
1359 "-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"
1360 " connect the host TAP network interface to VLAN 'n
'\n"
1361 " use network scripts 'file
' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1362 " to configure it and 'dfile
' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1363 " to deconfigure it\n"
1364 " use '[down
]script
=no
' to disable script execution\n"
1365 " use network helper 'helper
' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1367 " use 'fd
=h
' to connect to an already opened TAP interface\n"
1368 " use 'fds
=x
:y
:...:z
' to connect to already opened multiqueue capable TAP interfaces\n"
1369 " use 'sndbuf
=nbytes
' to limit the size of the send buffer (the\n"
1370 " default is disabled 'sndbuf
=0' to enable flow control set 'sndbuf
=1048576')\n"
1371 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1372 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1373 " use vhost=on to enable experimental in kernel accelerator\n"
1374 " (only has effect for virtio guests which use MSIX)\n"
1375 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1376 " use 'vhostfd
=h
' to connect to an already opened vhost net device\n"
1377 " use 'vhostfds
=x
:y
:...:z to connect to multiple already opened vhost net devices
\n"
1378 "-net bridge
[,vlan
=n
][,name
=str
][,br
=bridge
][,helper
=helper
]\n"
1379 " connects a host TAP network
interface to a host bridge device
'br'\n"
1380 " (default=" DEFAULT_BRIDGE_INTERFACE ") using the program
'helper'\n"
1381 " (default=" DEFAULT_BRIDGE_HELPER ")\n"
1383 "-net socket
[,vlan
=n
][,name
=str
][,fd
=h
][,listen
=[host
]:port
][,connect
=host
:port
]\n"
1384 " connect the vlan
'n' to another VLAN
using a socket connection
\n"
1385 "-net socket
[,vlan
=n
][,name
=str
][,fd
=h
][,mcast
=maddr
:port
[,localaddr
=addr
]]\n"
1386 " connect the vlan
'n' to multicast maddr and port
\n"
1387 " use
'localaddr=addr' to specify the host address to send packets from
\n"
1388 "-net socket
[,vlan
=n
][,name
=str
][,fd
=h
][,udp
=host
:port
][,localaddr
=host
:port
]\n"
1389 " connect the vlan
'n' to another VLAN
using an UDP tunnel
\n"
1391 "-net vde
[,vlan
=n
][,name
=str
][,sock
=socketpath
][,port
=n
][,group
=groupname
][,mode
=octalmode
]\n"
1392 " connect the vlan
'n' to port
'n' of a vde
switch running
\n"
1393 " on host and listening
for incoming connections on
'socketpath'.\n"
1394 " Use group
'groupname' and mode
'octalmode' to change
default\n"
1395 " ownership and permissions
for communication port
.\n"
1397 "-net dump
[,vlan
=n
][,file
=f
][,len
=n
]\n"
1398 " dump traffic on vlan
'n' to file
'f' (max n bytes per packet
)\n"
1399 "-net none use it alone to have zero network devices
. If no
-net option
\n"
1400 " is provided
, the
default is
'-net nic -net user'\n", QEMU_ARCH_ALL)
1401 DEF("netdev
", HAS_ARG, QEMU_OPTION_netdev,
1411 "socket
],id
=str
[,option
][,option
][,...]\n", QEMU_ARCH_ALL)
1413 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1415 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1416 = 0 is the default). The NIC is an e1000 by default on the PC
1417 target. Optionally, the MAC address can be changed to @var{mac}, the
1418 device address set to @var{addr} (PCI cards only),
1419 and a @var{name} can be assigned for use in monitor commands.
1420 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1421 that the card should have; this option currently only affects virtio cards; set
1422 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1423 NIC is created. QEMU can emulate several different models of network card.
1424 Valid values for @var{type} are
1425 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1426 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1427 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1428 Not all devices are supported on all targets. Use @code{-net nic,model=help}
1429 for a list of available devices for your target.
1431 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
1433 @item -net user[,@var{option}][,@var{option}][,...]
1434 Use the user mode network stack which requires no administrator
1435 privilege to run. Valid options are:
1439 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1442 @item name=@var{name}
1443 Assign symbolic name for use in monitor commands.
1445 @item net=@var{addr}[/@var{mask}]
1446 Set IP network address the guest will see. Optionally specify the netmask,
1447 either in the form a.b.c.d or as number of valid top-most bits. Default is
1450 @item host=@var{addr}
1451 Specify the guest-visible address of the host. Default is the 2nd IP in the
1452 guest network, i.e. x.x.x.2.
1454 @item restrict=on|off
1455 If this option is enabled, the guest will be isolated, i.e. it will not be
1456 able to contact the host and no guest IP packets will be routed over the host
1457 to the outside. This option does not affect any explicitly set forwarding rules.
1459 @item hostname=@var{name}
1460 Specifies the client hostname reported by the built-in DHCP server.
1462 @item dhcpstart=@var{addr}
1463 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1464 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1466 @item dns=@var{addr}
1467 Specify the guest-visible address of the virtual nameserver. The address must
1468 be different from the host address. Default is the 3rd IP in the guest network,
1471 @item dnssearch=@var{domain}
1472 Provides an entry for the domain-search list sent by the built-in
1473 DHCP server. More than one domain suffix can be transmitted by specifying
1474 this option multiple times. If supported, this will cause the guest to
1475 automatically try to append the given domain suffix(es) in case a domain name
1476 can not be resolved.
1480 qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
1483 @item tftp=@var{dir}
1484 When using the user mode network stack, activate a built-in TFTP
1485 server. The files in @var{dir} will be exposed as the root of a TFTP server.
1486 The TFTP client on the guest must be configured in binary mode (use the command
1487 @code{bin} of the Unix TFTP client).
1489 @item bootfile=@var{file}
1490 When using the user mode network stack, broadcast @var{file} as the BOOTP
1491 filename. In conjunction with @option{tftp}, this can be used to network boot
1492 a guest from a local directory.
1494 Example (using pxelinux):
1496 qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1499 @item smb=@var{dir}[,smbserver=@var{addr}]
1500 When using the user mode network stack, activate a built-in SMB
1501 server so that Windows OSes can access to the host files in @file{@var{dir}}
1502 transparently. The IP address of the SMB server can be set to @var{addr}. By
1503 default the 4th IP in the guest network is used, i.e. x.x.x.4.
1505 In the guest Windows OS, the line:
1509 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1510 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1512 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
1514 Note that a SAMBA server must be installed on the host OS.
1515 QEMU was tested successfully with smbd versions from Red Hat 9,
1516 Fedora Core 3 and OpenSUSE 11.x.
1518 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1519 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1520 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1521 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1522 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1523 be bound to a specific host interface. If no connection type is set, TCP is
1524 used. This option can be given multiple times.
1526 For example, to redirect host X11 connection from screen 1 to guest
1527 screen 0, use the following:
1531 qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1532 # this host xterm should open in the guest X11 server
1536 To redirect telnet connections from host port 5555 to telnet port on
1537 the guest, use the following:
1541 qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
1542 telnet localhost 5555
1545 Then when you use on the host @code{telnet localhost 5555}, you
1546 connect to the guest telnet server.
1548 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1549 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
1550 Forward guest TCP connections to the IP address @var{server} on port @var{port}
1551 to the character device @var{dev} or to a program executed by @var{cmd:command}
1552 which gets spawned for each connection. This option can be given multiple times.
1554 You can either use a chardev directly and have that one used throughout QEMU's
1555 lifetime, like in the following example:
1558 # open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
1559 # the guest accesses it
1560 qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...]
1563 Or you can execute a command on every TCP connection established by the guest,
1564 so that QEMU behaves similar to an inetd process for that virtual server:
1567 # call "netcat
10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
1568 # and connect the TCP stream to its stdin/stdout
1569 qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
1574 Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
1575 processed and applied to -net user. Mixing them with the new configuration
1576 syntax gives undefined results. Their use for new applications is discouraged
1577 as they will be removed from future versions.
1579 @item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1580 @item -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1581 Connect the host TAP network interface @var{name} to VLAN @var{n}.
1583 Use the network script @var{file} to configure it and the network script
1584 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
1585 automatically provides one. The default network configure script is
1586 @file{/etc/qemu-ifup} and the default network deconfigure script is
1587 @file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
1588 to disable script execution.
1590 If running QEMU as an unprivileged user, use the network helper
1591 @var{helper} to configure the TAP interface. The default network
1592 helper executable is @file{/usr/local/libexec/qemu-bridge-helper}.
1594 @option{fd}=@var{h} can be used to specify the handle of an already
1595 opened host TAP interface.
1600 #launch a QEMU instance with the default network script
1601 qemu-system-i386 linux.img -net nic -net tap
1605 #launch a QEMU instance with two NICs, each one connected
1607 qemu-system-i386 linux.img \
1608 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
1609 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
1613 #launch a QEMU instance with the default network helper to
1614 #connect a TAP device to bridge br0
1615 qemu-system-i386 linux.img \
1616 -net nic -net tap,"helper
=/usr
/local
/libexec
/qemu
-bridge
-helper
"
1619 @item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
1620 @item -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
1621 Connect a host TAP network interface to a host bridge device.
1623 Use the network helper @var{helper} to configure the TAP interface and
1624 attach it to the bridge. The default network helper executable is
1625 @file{/usr/local/libexec/qemu-bridge-helper} and the default bridge
1626 device is @file{br0}.
1631 #launch a QEMU instance with the default network helper to
1632 #connect a TAP device to bridge br0
1633 qemu-system-i386 linux.img -net bridge -net nic,model=virtio
1637 #launch a QEMU instance with the default network helper to
1638 #connect a TAP device to bridge qemubr0
1639 qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
1642 @item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1643 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1645 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
1646 machine using a TCP socket connection. If @option{listen} is
1647 specified, QEMU waits for incoming connections on @var{port}
1648 (@var{host} is optional). @option{connect} is used to connect to
1649 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
1650 specifies an already opened TCP socket.
1654 # launch a first QEMU instance
1655 qemu-system-i386 linux.img \
1656 -net nic,macaddr=52:54:00:12:34:56 \
1657 -net socket,listen=:1234
1658 # connect the VLAN 0 of this instance to the VLAN 0
1659 # of the first instance
1660 qemu-system-i386 linux.img \
1661 -net nic,macaddr=52:54:00:12:34:57 \
1662 -net socket,connect=127.0.0.1:1234
1665 @item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1666 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1668 Create a VLAN @var{n} shared with another QEMU virtual
1669 machines using a UDP multicast socket, effectively making a bus for
1670 every QEMU with same multicast address @var{maddr} and @var{port}.
1674 Several QEMU can be running on different hosts and share same bus (assuming
1675 correct multicast setup for these hosts).
1677 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
1678 @url{http://user-mode-linux.sf.net}.
1680 Use @option{fd=h} to specify an already opened UDP multicast socket.
1685 # launch one QEMU instance
1686 qemu-system-i386 linux.img \
1687 -net nic,macaddr=52:54:00:12:34:56 \
1688 -net socket,mcast=230.0.0.1:1234
1689 # launch another QEMU instance on same "bus
"
1690 qemu-system-i386 linux.img \
1691 -net nic,macaddr=52:54:00:12:34:57 \
1692 -net socket,mcast=230.0.0.1:1234
1693 # launch yet another QEMU instance on same "bus
"
1694 qemu-system-i386 linux.img \
1695 -net nic,macaddr=52:54:00:12:34:58 \
1696 -net socket,mcast=230.0.0.1:1234
1699 Example (User Mode Linux compat.):
1701 # launch QEMU instance (note mcast address selected
1703 qemu-system-i386 linux.img \
1704 -net nic,macaddr=52:54:00:12:34:56 \
1705 -net socket,mcast=239.192.168.1:1102
1707 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
1710 Example (send packets from host's 1.2.3.4):
1712 qemu-system-i386 linux.img \
1713 -net nic,macaddr=52:54:00:12:34:56 \
1714 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
1717 @item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1718 @item -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1719 Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
1720 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
1721 and MODE @var{octalmode} to change default ownership and permissions for
1722 communication port. This option is only available if QEMU has been compiled
1723 with vde support enabled.
1728 vde_switch -F -sock /tmp/myswitch
1729 # launch QEMU instance
1730 qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch
1733 @item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
1734 Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
1735 At most @var{len} bytes (64k by default) per packet are stored. The file format is
1736 libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
1739 Indicate that no network devices should be configured. It is used to
1740 override the default configuration (@option{-net nic -net user}) which
1741 is activated if no @option{-net} options are provided.
1749 DEFHEADING(Character device options:)
1752 The general form of a character device option is:
1756 DEF("chardev
", HAS_ARG, QEMU_OPTION_chardev,
1757 "-chardev
null,id
=id
[,mux
=on|off
]\n"
1758 "-chardev socket
,id
=id
[,host
=host
],port
=host
[,to
=to
][,ipv4
][,ipv6
][,nodelay
]\n"
1759 " [,server
][,nowait
][,telnet
][,mux
=on|off
] (tcp
)\n"
1760 "-chardev socket
,id
=id
,path
=path
[,server
][,nowait
][,telnet
],[mux
=on|off
] (unix
)\n"
1761 "-chardev udp
,id
=id
[,host
=host
],port
=port
[,localaddr
=localaddr
]\n"
1762 " [,localport
=localport
][,ipv4
][,ipv6
][,mux
=on|off
]\n"
1763 "-chardev msmouse
,id
=id
[,mux
=on|off
]\n"
1764 "-chardev vc
,id
=id
[[,width
=width
][,height
=height
]][[,cols
=cols
][,rows
=rows
]]\n"
1766 "-chardev ringbuf
,id
=id
[,size
=size
]\n"
1767 "-chardev file
,id
=id
,path
=path
[,mux
=on|off
]\n"
1768 "-chardev pipe
,id
=id
,path
=path
[,mux
=on|off
]\n"
1770 "-chardev console
,id
=id
[,mux
=on|off
]\n"
1771 "-chardev serial
,id
=id
,path
=path
[,mux
=on|off
]\n"
1773 "-chardev pty
,id
=id
[,mux
=on|off
]\n"
1774 "-chardev stdio
,id
=id
[,mux
=on|off
][,signal
=on|off
]\n"
1776 #ifdef CONFIG_BRLAPI
1777 "-chardev braille
,id
=id
[,mux
=on|off
]\n"
1779 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
1780 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
1781 "-chardev serial
,id
=id
,path
=path
[,mux
=on|off
]\n"
1782 "-chardev tty
,id
=id
,path
=path
[,mux
=on|off
]\n"
1784 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
1785 "-chardev parallel
,id
=id
,path
=path
[,mux
=on|off
]\n"
1786 "-chardev parport
,id
=id
,path
=path
[,mux
=on|off
]\n"
1788 #if defined(CONFIG_SPICE)
1789 "-chardev spicevmc
,id
=id
,name
=name
[,debug
=debug
]\n"
1790 "-chardev spiceport
,id
=id
,name
=name
[,debug
=debug
]\n"
1796 @item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
1817 The specific backend will determine the applicable options.
1819 All devices must have an id, which can be any string up to 127 characters long.
1820 It is used to uniquely identify this device in other command line directives.
1822 A character device may be used in multiplexing mode by multiple front-ends.
1823 The key sequence of @key{Control-a} and @key{c} will rotate the input focus
1824 between attached front-ends. Specify @option{mux=on} to enable this mode.
1826 Options to each backend are described below.
1828 @item -chardev null ,id=@var{id}
1829 A void device. This device will not emit any data, and will drop any data it
1830 receives. The null backend does not take any options.
1832 @item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet]
1834 Create a two-way stream socket, which can be either a TCP or a unix socket. A
1835 unix socket will be created if @option{path} is specified. Behaviour is
1836 undefined if TCP options are specified for a unix socket.
1838 @option{server} specifies that the socket shall be a listening socket.
1840 @option{nowait} specifies that QEMU should not block waiting for a client to
1841 connect to a listening socket.
1843 @option{telnet} specifies that traffic on the socket should interpret telnet
1846 TCP and unix socket options are given below:
1850 @item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
1852 @option{host} for a listening socket specifies the local address to be bound.
1853 For a connecting socket species the remote host to connect to. @option{host} is
1854 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
1856 @option{port} for a listening socket specifies the local port to be bound. For a
1857 connecting socket specifies the port on the remote host to connect to.
1858 @option{port} can be given as either a port number or a service name.
1859 @option{port} is required.
1861 @option{to} is only relevant to listening sockets. If it is specified, and
1862 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
1863 to and including @option{to} until it succeeds. @option{to} must be specified
1866 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1867 If neither is specified the socket may use either protocol.
1869 @option{nodelay} disables the Nagle algorithm.
1871 @item unix options: path=@var{path}
1873 @option{path} specifies the local path of the unix socket. @option{path} is
1878 @item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
1880 Sends all traffic from the guest to a remote host over UDP.
1882 @option{host} specifies the remote host to connect to. If not specified it
1883 defaults to @code{localhost}.
1885 @option{port} specifies the port on the remote host to connect to. @option{port}
1888 @option{localaddr} specifies the local address to bind to. If not specified it
1889 defaults to @code{0.0.0.0}.
1891 @option{localport} specifies the local port to bind to. If not specified any
1892 available local port will be used.
1894 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1895 If neither is specified the device may use either protocol.
1897 @item -chardev msmouse ,id=@var{id}
1899 Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
1902 @item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
1904 Connect to a QEMU text console. @option{vc} may optionally be given a specific
1907 @option{width} and @option{height} specify the width and height respectively of
1908 the console, in pixels.
1910 @option{cols} and @option{rows} specify that the console be sized to fit a text
1911 console with the given dimensions.
1913 @item -chardev ringbuf ,id=@var{id} [,size=@var{size}]
1915 Create a ring buffer with fixed size @option{size}.
1916 @var{size} must be a power of two, and defaults to @code{64K}).
1918 @item -chardev file ,id=@var{id} ,path=@var{path}
1920 Log all traffic received from the guest to a file.
1922 @option{path} specifies the path of the file to be opened. This file will be
1923 created if it does not already exist, and overwritten if it does. @option{path}
1926 @item -chardev pipe ,id=@var{id} ,path=@var{path}
1928 Create a two-way connection to the guest. The behaviour differs slightly between
1929 Windows hosts and other hosts:
1931 On Windows, a single duplex pipe will be created at
1932 @file{\\.pipe\@option{path}}.
1934 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
1935 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
1936 received by the guest. Data written by the guest can be read from
1937 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
1940 @option{path} forms part of the pipe path as described above. @option{path} is
1943 @item -chardev console ,id=@var{id}
1945 Send traffic from the guest to QEMU's standard output. @option{console} does not
1948 @option{console} is only available on Windows hosts.
1950 @item -chardev serial ,id=@var{id} ,path=@option{path}
1952 Send traffic from the guest to a serial device on the host.
1954 On Unix hosts serial will actually accept any tty device,
1955 not only serial lines.
1957 @option{path} specifies the name of the serial device to open.
1959 @item -chardev pty ,id=@var{id}
1961 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
1962 not take any options.
1964 @option{pty} is not available on Windows hosts.
1966 @item -chardev stdio ,id=@var{id} [,signal=on|off]
1967 Connect to standard input and standard output of the QEMU process.
1969 @option{signal} controls if signals are enabled on the terminal, that includes
1970 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
1971 default, use @option{signal=off} to disable it.
1973 @option{stdio} is not available on Windows hosts.
1975 @item -chardev braille ,id=@var{id}
1977 Connect to a local BrlAPI server. @option{braille} does not take any options.
1979 @item -chardev tty ,id=@var{id} ,path=@var{path}
1981 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
1982 DragonFlyBSD hosts. It is an alias for @option{serial}.
1984 @option{path} specifies the path to the tty. @option{path} is required.
1986 @item -chardev parallel ,id=@var{id} ,path=@var{path}
1987 @item -chardev parport ,id=@var{id} ,path=@var{path}
1989 @option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
1991 Connect to a local parallel port.
1993 @option{path} specifies the path to the parallel port device. @option{path} is
1996 @item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
1998 @option{spicevmc} is only available when spice support is built in.
2000 @option{debug} debug level for spicevmc
2002 @option{name} name of spice channel to connect to
2004 Connect to a spice virtual machine channel, such as vdiport.
2006 @item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2008 @option{spiceport} is only available when spice support is built in.
2010 @option{debug} debug level for spicevmc
2012 @option{name} name of spice port to connect to
2014 Connect to a spice port, allowing a Spice client to handle the traffic
2015 identified by a name (preferably a fqdn).
2023 DEFHEADING(Device URL Syntax:)
2026 In addition to using normal file images for the emulated storage devices,
2027 QEMU can also use networked resources such as iSCSI devices. These are
2028 specified using a special URL syntax.
2032 iSCSI support allows QEMU to access iSCSI resources directly and use as
2033 images for the guest storage. Both disk and cdrom images are supported.
2035 Syntax for specifying iSCSI LUNs is
2036 ``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
2038 By default qemu will use the iSCSI initiator-name
2039 'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command
2040 line or a configuration file.
2043 Example (without authentication):
2045 qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
2046 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
2047 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2050 Example (CHAP username/password via URL):
2052 qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
2055 Example (CHAP username/password via environment variables):
2057 LIBISCSI_CHAP_USERNAME="user
" \
2058 LIBISCSI_CHAP_PASSWORD="password
" \
2059 qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2062 iSCSI support is an optional feature of QEMU and only available when
2063 compiled and linked against libiscsi.
2065 DEF("iscsi
", HAS_ARG, QEMU_OPTION_iscsi,
2066 "-iscsi
[user
=user
][,password
=password
]\n"
2067 " [,header
-digest
=CRC32C|CR32C
-NONE|NONE
-CRC32C|NONE
\n"
2068 " [,initiator
-name
=iqn
]\n"
2069 " iSCSI session parameters
\n", QEMU_ARCH_ALL)
2072 iSCSI parameters such as username and password can also be specified via
2073 a configuration file. See qemu-doc for more information and examples.
2076 QEMU supports NBD (Network Block Devices) both using TCP protocol as well
2077 as Unix Domain Sockets.
2079 Syntax for specifying a NBD device using TCP
2080 ``nbd:<server-ip>:<port>[:exportname=<export>]''
2082 Syntax for specifying a NBD device using Unix Domain Sockets
2083 ``nbd:unix:<domain-socket>[:exportname=<export>]''
2088 qemu-system-i386 --drive file=nbd:192.0.2.1:30000
2091 Example for Unix Domain Sockets
2093 qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket
2097 Sheepdog is a distributed storage system for QEMU.
2098 QEMU supports using either local sheepdog devices or remote networked
2101 Syntax for specifying a sheepdog device
2103 sheepdog[+tcp]://[host:port]/vdiname[#snapid|#tag]
2108 qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine
2111 See also @url{http://http://www.osrg.net/sheepdog/}.
2114 GlusterFS is an user space distributed file system.
2115 QEMU supports the use of GlusterFS volumes for hosting VM disk images using
2116 TCP, Unix Domain Sockets and RDMA transport protocols.
2118 Syntax for specifying a VM disk image on GlusterFS volume is
2120 gluster[+transport]://[server[:port]]/volname/image[?socket=...]
2126 qemu-system-x86_84 --drive file=gluster://192.0.2.1/testvol/a.img
2129 See also @url{http://www.gluster.org}.
2136 DEFHEADING(Bluetooth(R) options:)
2141 DEF("bt
", HAS_ARG, QEMU_OPTION_bt, \
2142 "-bt hci
,null dumb bluetooth HCI
- doesn
't respond to commands\n" \
2143 "-bt hci,host[:id]\n" \
2144 " use host's HCI with the given name
\n" \
2145 "-bt hci
[,vlan
=n
]\n" \
2146 " emulate a standard HCI
in virtual scatternet
'n'\n" \
2147 "-bt vhci
[,vlan
=n
]\n" \
2148 " add host computer to virtual scatternet
'n' using VHCI
\n" \
2149 "-bt device
:dev
[,vlan
=n
]\n" \
2150 " emulate a bluetooth device
'dev' in scatternet
'n'\n",
2155 Defines the function of the corresponding Bluetooth HCI. -bt options
2156 are matched with the HCIs present in the chosen machine type. For
2157 example when emulating a machine with only one HCI built into it, only
2158 the first @code{-bt hci[...]} option is valid and defines the HCI's
2159 logic. The Transport Layer is decided by the machine type. Currently
2160 the machines @code{n800} and @code{n810} have one HCI and all other
2164 The following three types are recognized:
2168 (default) The corresponding Bluetooth HCI assumes no internal logic
2169 and will not respond to any HCI commands or emit events.
2171 @item -bt hci,host[:@var{id}]
2172 (@code{bluez} only) The corresponding HCI passes commands / events
2173 to / from the physical HCI identified by the name @var{id} (default:
2174 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
2175 capable systems like Linux.
2177 @item -bt hci[,vlan=@var{n}]
2178 Add a virtual, standard HCI that will participate in the Bluetooth
2179 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
2180 VLANs, devices inside a bluetooth network @var{n} can only communicate
2181 with other devices in the same network (scatternet).
2184 @item -bt vhci[,vlan=@var{n}]
2185 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2186 to the host bluetooth stack instead of to the emulated target. This
2187 allows the host and target machines to participate in a common scatternet
2188 and communicate. Requires the Linux @code{vhci} driver installed. Can
2189 be used as following:
2192 qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2195 @item -bt device:@var{dev}[,vlan=@var{n}]
2196 Emulate a bluetooth device @var{dev} and place it in network @var{n}
2197 (default @code{0}). QEMU can only emulate one type of bluetooth devices
2202 Virtual wireless keyboard implementing the HIDP bluetooth profile.
2211 DEFHEADING(Linux/Multiboot boot specific:)
2214 When using these options, you can use a given Linux or Multiboot
2215 kernel without installing it in the disk image. It can be useful
2216 for easier testing of various kernels.
2221 DEF("kernel
", HAS_ARG, QEMU_OPTION_kernel, \
2222 "-kernel bzImage use
'bzImage' as kernel image
\n", QEMU_ARCH_ALL)
2224 @item -kernel @var{bzImage}
2226 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2227 or in multiboot format.
2230 DEF("append
", HAS_ARG, QEMU_OPTION_append, \
2231 "-append cmdline use
'cmdline' as kernel command line
\n", QEMU_ARCH_ALL)
2233 @item -append @var{cmdline}
2235 Use @var{cmdline} as kernel command line
2238 DEF("initrd
", HAS_ARG, QEMU_OPTION_initrd, \
2239 "-initrd file use
'file' as initial ram disk
\n", QEMU_ARCH_ALL)
2241 @item -initrd @var{file}
2243 Use @var{file} as initial ram disk.
2245 @item -initrd "@
var{file1
} arg
=foo
,@
var{file2
}"
2247 This syntax is only available with multiboot.
2249 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
2253 DEF("dtb
", HAS_ARG, QEMU_OPTION_dtb, \
2254 "-dtb file use
'file' as device tree image
\n", QEMU_ARCH_ALL)
2256 @item -dtb @var{file}
2258 Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
2267 DEFHEADING(Debug/Expert options:)
2272 DEF("serial
", HAS_ARG, QEMU_OPTION_serial, \
2273 "-serial dev redirect the serial port to char device
'dev'\n",
2276 @item -serial @var{dev}
2278 Redirect the virtual serial port to host character device
2279 @var{dev}. The default device is @code{vc} in graphical mode and
2280 @code{stdio} in non graphical mode.
2282 This option can be used several times to simulate up to 4 serial
2285 Use @code{-serial none} to disable all serial ports.
2287 Available character devices are:
2289 @item vc[:@var{W}x@var{H}]
2290 Virtual console. Optionally, a width and height can be given in pixel with
2294 It is also possible to specify width or height in characters:
2299 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
2301 No device is allocated.
2305 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
2306 parameters are set according to the emulated ones.
2307 @item /dev/parport@var{N}
2308 [Linux only, parallel port only] Use host parallel port
2309 @var{N}. Currently SPP and EPP parallel port features can be used.
2310 @item file:@var{filename}
2311 Write output to @var{filename}. No character can be read.
2313 [Unix only] standard input/output
2314 @item pipe:@var{filename}
2315 name pipe @var{filename}
2317 [Windows only] Use host serial port @var{n}
2318 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
2319 This implements UDP Net Console.
2320 When @var{remote_host} or @var{src_ip} are not specified
2321 they default to @code{0.0.0.0}.
2322 When not using a specified @var{src_port} a random port is automatically chosen.
2324 If you just want a simple readonly console you can use @code{netcat} or
2325 @code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
2326 @code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
2327 will appear in the netconsole session.
2329 If you plan to send characters back via netconsole or you want to stop
2330 and start QEMU a lot of times, you should have QEMU use the same
2331 source port each time by using something like @code{-serial
2332 udp::4555@@:4556} to QEMU. Another approach is to use a patched
2333 version of netcat which can listen to a TCP port and send and receive
2334 characters via udp. If you have a patched version of netcat which
2335 activates telnet remote echo and single char transfer, then you can
2336 use the following options to step up a netcat redirector to allow
2337 telnet on port 5555 to access the QEMU port.
2340 -serial udp::4555@@:4556
2341 @item netcat options:
2342 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
2343 @item telnet options:
2347 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay]
2348 The TCP Net Console has two modes of operation. It can send the serial
2349 I/O to a location or wait for a connection from a location. By default
2350 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
2351 the @var{server} option QEMU will wait for a client socket application
2352 to connect to the port before continuing, unless the @code{nowait}
2353 option was specified. The @code{nodelay} option disables the Nagle buffering
2354 algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only
2355 one TCP connection at a time is accepted. You can use @code{telnet} to
2356 connect to the corresponding character device.
2358 @item Example to send tcp console to 192.168.0.2 port 4444
2359 -serial tcp:192.168.0.2:4444
2360 @item Example to listen and wait on port 4444 for connection
2361 -serial tcp::4444,server
2362 @item Example to not wait and listen on ip 192.168.0.100 port 4444
2363 -serial tcp:192.168.0.100:4444,server,nowait
2366 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
2367 The telnet protocol is used instead of raw tcp sockets. The options
2368 work the same as if you had specified @code{-serial tcp}. The
2369 difference is that the port acts like a telnet server or client using
2370 telnet option negotiation. This will also allow you to send the
2371 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
2372 sequence. Typically in unix telnet you do it with Control-] and then
2373 type "send
break" followed by pressing the enter key.
2375 @item unix:@var{path}[,server][,nowait]
2376 A unix domain socket is used instead of a tcp socket. The option works the
2377 same as if you had specified @code{-serial tcp} except the unix domain socket
2378 @var{path} is used for connections.
2380 @item mon:@var{dev_string}
2381 This is a special option to allow the monitor to be multiplexed onto
2382 another serial port. The monitor is accessed with key sequence of
2383 @key{Control-a} and then pressing @key{c}. See monitor access
2384 @ref{pcsys_keys} in the -nographic section for more keys.
2385 @var{dev_string} should be any one of the serial devices specified
2386 above. An example to multiplex the monitor onto a telnet server
2387 listening on port 4444 would be:
2389 @item -serial mon:telnet::4444,server,nowait
2393 Braille device. This will use BrlAPI to display the braille output on a real
2397 Three button serial mouse. Configure the guest to use Microsoft protocol.
2401 DEF("parallel
", HAS_ARG, QEMU_OPTION_parallel, \
2402 "-parallel dev redirect the parallel port to char device
'dev'\n",
2405 @item -parallel @var{dev}
2407 Redirect the virtual parallel port to host device @var{dev} (same
2408 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
2409 be used to use hardware devices connected on the corresponding host
2412 This option can be used several times to simulate up to 3 parallel
2415 Use @code{-parallel none} to disable all parallel ports.
2418 DEF("monitor
", HAS_ARG, QEMU_OPTION_monitor, \
2419 "-monitor dev redirect the monitor to char device
'dev'\n",
2422 @item -monitor @var{dev}
2424 Redirect the monitor to host device @var{dev} (same devices as the
2426 The default device is @code{vc} in graphical mode and @code{stdio} in
2429 DEF("qmp
", HAS_ARG, QEMU_OPTION_qmp, \
2430 "-qmp dev like
-monitor but opens
in 'control' mode
\n",
2433 @item -qmp @var{dev}
2435 Like -monitor but opens in 'control' mode.
2438 DEF("mon
", HAS_ARG, QEMU_OPTION_mon, \
2439 "-mon chardev
=[name
][,mode
=readline|control
][,default]\n", QEMU_ARCH_ALL)
2441 @item -mon chardev=[name][,mode=readline|control][,default]
2443 Setup monitor on chardev @var{name}.
2446 DEF("debugcon
", HAS_ARG, QEMU_OPTION_debugcon, \
2447 "-debugcon dev redirect the debug console to char device
'dev'\n",
2450 @item -debugcon @var{dev}
2452 Redirect the debug console to host device @var{dev} (same devices as the
2453 serial port). The debug console is an I/O port which is typically port
2454 0xe9; writing to that I/O port sends output to this device.
2455 The default device is @code{vc} in graphical mode and @code{stdio} in
2459 DEF("pidfile
", HAS_ARG, QEMU_OPTION_pidfile, \
2460 "-pidfile file write PID to
'file'\n", QEMU_ARCH_ALL)
2462 @item -pidfile @var{file}
2464 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
2468 DEF("singlestep
", 0, QEMU_OPTION_singlestep, \
2469 "-singlestep always run
in singlestep mode
\n", QEMU_ARCH_ALL)
2473 Run the emulation in single step mode.
2476 DEF("S
", 0, QEMU_OPTION_S, \
2477 "-S freeze CPU at
startup (use
'c' to start execution
)\n",
2482 Do not start CPU at startup (you must type 'c' in the monitor).
2485 DEF("gdb
", HAS_ARG, QEMU_OPTION_gdb, \
2486 "-gdb dev wait
for gdb connection on
'dev'\n", QEMU_ARCH_ALL)
2488 @item -gdb @var{dev}
2490 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
2491 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
2492 stdio are reasonable use case. The latter is allowing to start QEMU from
2493 within gdb and establish the connection via a pipe:
2495 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
2499 DEF("s
", 0, QEMU_OPTION_s, \
2500 "-s shorthand
for -gdb tcp
::" DEFAULT_GDBSTUB_PORT "\n",
2505 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
2506 (@pxref{gdb_usage}).
2509 DEF("d
", HAS_ARG, QEMU_OPTION_d, \
2510 "-d item1
,... enable logging of specified
items (use
'-d help' for a list of log items
)\n",
2513 @item -d @var{item1}[,...]
2515 Enable logging of specified items. Use '-d help' for a list of log items.
2518 DEF("D
", HAS_ARG, QEMU_OPTION_D, \
2519 "-D logfile output log to
logfile (default stderr
)\n",
2522 @item -D @var{logfile}
2524 Output log in @var{logfile} instead of to stderr
2527 DEF("L
", HAS_ARG, QEMU_OPTION_L, \
2528 "-L path set the directory
for the BIOS
, VGA BIOS and keymaps
\n",
2533 Set the directory for the BIOS, VGA BIOS and keymaps.
2536 DEF("bios
", HAS_ARG, QEMU_OPTION_bios, \
2537 "-bios file set the filename
for the BIOS
\n", QEMU_ARCH_ALL)
2539 @item -bios @var{file}
2541 Set the filename for the BIOS.
2544 DEF("enable
-kvm
", 0, QEMU_OPTION_enable_kvm, \
2545 "-enable
-kvm enable KVM full virtualization support
\n", QEMU_ARCH_ALL)
2549 Enable KVM full virtualization support. This option is only available
2550 if KVM support is enabled when compiling.
2553 DEF("xen
-domid
", HAS_ARG, QEMU_OPTION_xen_domid,
2554 "-xen
-domid id specify xen guest domain id
\n", QEMU_ARCH_ALL)
2555 DEF("xen
-create
", 0, QEMU_OPTION_xen_create,
2556 "-xen
-create create domain
using xen hypercalls
, bypassing xend
\n"
2557 " warning
: should not be used when xend is
in use
\n",
2559 DEF("xen
-attach
", 0, QEMU_OPTION_xen_attach,
2560 "-xen
-attach attach to existing xen domain
\n"
2561 " xend will use
this when starting QEMU
\n",
2564 @item -xen-domid @var{id}
2566 Specify xen guest domain @var{id} (XEN only).
2569 Create domain using xen hypercalls, bypassing xend.
2570 Warning: should not be used when xend is in use (XEN only).
2573 Attach to existing xen domain.
2574 xend will use this when starting QEMU (XEN only).
2577 DEF("no
-reboot
", 0, QEMU_OPTION_no_reboot, \
2578 "-no
-reboot exit instead of rebooting
\n", QEMU_ARCH_ALL)
2582 Exit instead of rebooting.
2585 DEF("no
-shutdown
", 0, QEMU_OPTION_no_shutdown, \
2586 "-no
-shutdown stop before shutdown
\n", QEMU_ARCH_ALL)
2589 @findex -no-shutdown
2590 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
2591 This allows for instance switching to monitor to commit changes to the
2595 DEF("loadvm
", HAS_ARG, QEMU_OPTION_loadvm, \
2596 "-loadvm
[tag|id
]\n" \
2597 " start right away with a saved
state (loadvm
in monitor
)\n",
2600 @item -loadvm @var{file}
2602 Start right away with a saved state (@code{loadvm} in monitor)
2606 DEF("daemonize
", 0, QEMU_OPTION_daemonize, \
2607 "-daemonize daemonize QEMU after initializing
\n", QEMU_ARCH_ALL)
2612 Daemonize the QEMU process after initialization. QEMU will not detach from
2613 standard IO until it is ready to receive connections on any of its devices.
2614 This option is a useful way for external programs to launch QEMU without having
2615 to cope with initialization race conditions.
2618 DEF("option
-rom
", HAS_ARG, QEMU_OPTION_option_rom, \
2619 "-option
-rom rom load a file
, rom
, into the option ROM space
\n",
2622 @item -option-rom @var{file}
2624 Load the contents of @var{file} as an option ROM.
2625 This option is useful to load things like EtherBoot.
2628 DEF("clock
", HAS_ARG, QEMU_OPTION_clock, \
2629 "-clock force the use of the given methods
for timer alarm
.\n" \
2630 " To see what timers are available use
'-clock help'\n",
2633 @item -clock @var{method}
2635 Force the use of the given methods for timer alarm. To see what timers
2636 are available use @code{-clock help}.
2639 HXCOMM Options deprecated by -rtc
2640 DEF("localtime
", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
2641 DEF("startdate
", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
2643 DEF("rtc
", HAS_ARG, QEMU_OPTION_rtc, \
2644 "-rtc
[base
=utc|localtime|date
][,clock
=host|rt|vm
][,driftfix
=none|slew
]\n" \
2645 " set the RTC base and clock
, enable drift fix
for clock
ticks (x86 only
)\n",
2650 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
2652 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
2653 UTC or local time, respectively. @code{localtime} is required for correct date in
2654 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
2655 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
2657 By default the RTC is driven by the host system time. This allows to use the
2658 RTC as accurate reference clock inside the guest, specifically if the host
2659 time is smoothly following an accurate external reference clock, e.g. via NTP.
2660 If you want to isolate the guest time from the host, you can set @option{clock}
2661 to @code{rt} instead. To even prevent it from progressing during suspension,
2662 you can set it to @code{vm}.
2664 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
2665 specifically with Windows' ACPI HAL. This option will try to figure out how
2666 many timer interrupts were not processed by the Windows guest and will
2670 DEF("icount
", HAS_ARG, QEMU_OPTION_icount, \
2671 "-icount
[N|auto
]\n" \
2672 " enable virtual instruction counter with
2^N clock ticks per
\n" \
2673 " instruction
\n", QEMU_ARCH_ALL)
2675 @item -icount [@var{N}|auto]
2677 Enable virtual instruction counter. The virtual cpu will execute one
2678 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
2679 then the virtual cpu speed will be automatically adjusted to keep virtual
2680 time within a few seconds of real time.
2682 Note that while this option can give deterministic behavior, it does not
2683 provide cycle accurate emulation. Modern CPUs contain superscalar out of
2684 order cores with complex cache hierarchies. The number of instructions
2685 executed often has little or no correlation with actual performance.
2688 DEF("watchdog
", HAS_ARG, QEMU_OPTION_watchdog, \
2689 "-watchdog i6300esb|ib700
\n" \
2690 " enable virtual hardware watchdog
[default=none
]\n",
2693 @item -watchdog @var{model}
2695 Create a virtual hardware watchdog device. Once enabled (by a guest
2696 action), the watchdog must be periodically polled by an agent inside
2697 the guest or else the guest will be restarted.
2699 The @var{model} is the model of hardware watchdog to emulate. Choices
2700 for model are: @code{ib700} (iBASE 700) which is a very simple ISA
2701 watchdog with a single timer, or @code{i6300esb} (Intel 6300ESB I/O
2702 controller hub) which is a much more featureful PCI-based dual-timer
2703 watchdog. Choose a model for which your guest has drivers.
2705 Use @code{-watchdog help} to list available hardware models. Only one
2706 watchdog can be enabled for a guest.
2709 DEF("watchdog
-action
", HAS_ARG, QEMU_OPTION_watchdog_action, \
2710 "-watchdog
-action reset|shutdown|poweroff|pause|debug|none
\n" \
2711 " action when watchdog fires
[default=reset
]\n",
2714 @item -watchdog-action @var{action}
2715 @findex -watchdog-action
2717 The @var{action} controls what QEMU will do when the watchdog timer
2720 @code{reset} (forcefully reset the guest).
2721 Other possible actions are:
2722 @code{shutdown} (attempt to gracefully shutdown the guest),
2723 @code{poweroff} (forcefully poweroff the guest),
2724 @code{pause} (pause the guest),
2725 @code{debug} (print a debug message and continue), or
2726 @code{none} (do nothing).
2728 Note that the @code{shutdown} action requires that the guest responds
2729 to ACPI signals, which it may not be able to do in the sort of
2730 situations where the watchdog would have expired, and thus
2731 @code{-watchdog-action shutdown} is not recommended for production use.
2736 @item -watchdog i6300esb -watchdog-action pause
2737 @item -watchdog ib700
2741 DEF("echr
", HAS_ARG, QEMU_OPTION_echr, \
2742 "-echr chr set terminal escape character instead of ctrl
-a
\n",
2746 @item -echr @var{numeric_ascii_value}
2748 Change the escape character used for switching to the monitor when using
2749 monitor and serial sharing. The default is @code{0x01} when using the
2750 @code{-nographic} option. @code{0x01} is equal to pressing
2751 @code{Control-a}. You can select a different character from the ascii
2752 control keys where 1 through 26 map to Control-a through Control-z. For
2753 instance you could use the either of the following to change the escape
2754 character to Control-t.
2761 DEF("virtioconsole
", HAS_ARG, QEMU_OPTION_virtiocon, \
2762 "-virtioconsole c
\n" \
2763 " set virtio console
\n", QEMU_ARCH_ALL)
2765 @item -virtioconsole @var{c}
2766 @findex -virtioconsole
2769 This option is maintained for backward compatibility.
2771 Please use @code{-device virtconsole} for the new way of invocation.
2774 DEF("show
-cursor
", 0, QEMU_OPTION_show_cursor, \
2775 "-show
-cursor show cursor
\n", QEMU_ARCH_ALL)
2778 @findex -show-cursor
2782 DEF("tb
-size
", HAS_ARG, QEMU_OPTION_tb_size, \
2783 "-tb
-size n set TB size
\n", QEMU_ARCH_ALL)
2785 @item -tb-size @var{n}
2790 DEF("incoming
", HAS_ARG, QEMU_OPTION_incoming, \
2791 "-incoming p prepare
for incoming migration
, listen on port p
\n",
2794 @item -incoming @var{port}
2796 Prepare for incoming migration, listen on @var{port}.
2799 DEF("nodefaults
", 0, QEMU_OPTION_nodefaults, \
2800 "-nodefaults don
't create default devices\n", QEMU_ARCH_ALL)
2804 Don't create
default devices
. Normally
, QEMU sets the
default devices like serial
2805 port
, parallel port
, virtual console
, monitor device
, VGA adapter
, floppy and
2806 CD
-ROM drive and others
. The @code
{-nodefaults
} option will disable all those
2811 DEF("chroot", HAS_ARG
, QEMU_OPTION_chroot
, \
2812 "-chroot dir chroot to dir just before starting the VM\n",
2816 @item
-chroot @
var{dir
}
2818 Immediately before starting guest execution
, chroot to the specified
2819 directory
. Especially useful
in combination with
-runas
.
2823 DEF("runas", HAS_ARG
, QEMU_OPTION_runas
, \
2824 "-runas user change to user id user just before starting the VM\n",
2828 @item
-runas @
var{user
}
2830 Immediately before starting guest execution
, drop root privileges
, switching
2831 to the specified user
.
2834 DEF("prom-env", HAS_ARG
, QEMU_OPTION_prom_env
,
2835 "-prom-env variable=value\n"
2836 " set OpenBIOS nvram variables\n",
2837 QEMU_ARCH_PPC | QEMU_ARCH_SPARC
)
2839 @item
-prom
-env @
var{variable
}=@
var{value
}
2841 Set OpenBIOS nvram @
var{variable
} to given @
var{value
} (PPC
, SPARC only
).
2843 DEF("semihosting", 0, QEMU_OPTION_semihosting
,
2844 "-semihosting semihosting mode\n", QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA
)
2847 @findex
-semihosting
2848 Semihosting
mode (ARM
, M68K
, Xtensa only
).
2850 DEF("old-param", 0, QEMU_OPTION_old_param
,
2851 "-old-param old param mode\n", QEMU_ARCH_ARM
)
2854 @findex
-old
-param (ARM
)
2855 Old param
mode (ARM only
).
2858 DEF("sandbox", HAS_ARG
, QEMU_OPTION_sandbox
, \
2859 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n",
2862 @item
-sandbox @
var{arg
}
2864 Enable Seccomp mode
2 system call filter
. 'on' will enable syscall filtering and
'off' will
2865 disable it
. The
default is
'off'.
2868 DEF("readconfig", HAS_ARG
, QEMU_OPTION_readconfig
,
2869 "-readconfig <file>\n", QEMU_ARCH_ALL
)
2871 @item
-readconfig @
var{file
}
2873 Read device configuration from @
var{file
}. This approach is useful when you want to spawn
2874 QEMU process with many command line options but you don
't want to exceed the command line
2877 DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
2878 "-writeconfig <file>\n"
2879 " read/write config file\n", QEMU_ARCH_ALL)
2881 @item -writeconfig @var{file}
2882 @findex -writeconfig
2883 Write device configuration to @var{file}. The @var{file} can be either filename to save
2884 command line and device configuration into file or dash @code{-}) character to print the
2885 output to stdout. This can be later used as input file for @code{-readconfig} option.
2887 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig,
2889 " do not load default config files at startup\n",
2893 @findex -nodefconfig
2894 Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
2895 The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
2897 DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
2899 " do not load user-provided config files at startup\n",
2902 @item -no-user-config
2903 @findex -no-user-config
2904 The @code{-no-user-config} option makes QEMU not load any of the user-provided
2905 config files on @var{sysconfdir}, but won't make it skip the QEMU
-provided config
2906 files from @
var{datadir
}.
2908 DEF("trace", HAS_ARG
, QEMU_OPTION_trace
,
2909 "-trace [events=<file>][,file=<file>]\n"
2910 " specify tracing options\n",
2913 HXCOMM This line is not accurate
, as some sub
-options are backend
-specific but
2914 HXCOMM HX does not support conditional compilation of text
.
2915 @item
-trace [events
=@
var{file
}][,file
=@
var{file
}]
2918 Specify tracing options
.
2921 @item events
=@
var{file
}
2922 Immediately enable events listed
in @
var{file
}.
2923 The file must contain one event
name (as listed
in the @
var{trace-events
} file
)
2925 This option is only available
if QEMU has been compiled with
2926 either @
var{simple
} or @
var{stderr
} tracing backend
.
2927 @item file
=@
var{file
}
2928 Log output traces to @
var{file
}.
2930 This option is only available
if QEMU has been compiled with
2931 the @
var{simple
} tracing backend
.
2936 DEF("qtest", HAS_ARG
, QEMU_OPTION_qtest
, "", QEMU_ARCH_ALL
)
2937 DEF("qtest-log", HAS_ARG
, QEMU_OPTION_qtest_log
, "", QEMU_ARCH_ALL
)
2940 DEF("enable-fips", 0, QEMU_OPTION_enablefips
,
2941 "-enable-fips enable FIPS 140-2 compliance\n",
2946 @findex
-enable
-fips
2947 Enable FIPS
140-2 compliance mode
.
2950 HXCOMM Deprecated by
-machine accel
=tcg property
2951 DEF("no-kvm", 0, QEMU_OPTION_no_kvm
, "", QEMU_ARCH_I386
)
2953 HXCOMM Deprecated by kvm
-pit driver properties
2954 DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection
,
2957 HXCOMM
Deprecated (ignored
)
2958 DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit
, "", QEMU_ARCH_I386
)
2960 HXCOMM Deprecated by
-machine kernel_irqchip
=on|off property
2961 DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip
, "", QEMU_ARCH_I386
)
2963 HXCOMM
Deprecated (ignored
)
2964 DEF("tdf", 0, QEMU_OPTION_tdf
,"", QEMU_ARCH_ALL
)
2966 DEF("object", HAS_ARG
, QEMU_OPTION_object
,
2967 "-object TYPENAME[,PROP1=VALUE1,...]\n"
2968 " create an new object of type TYPENAME setting properties\n"
2969 " in the order they are specified. Note that the 'id'\n"
2970 " property must be set. These objects are placed in the\n"
2971 " '/objects' path.\n",
2974 @item
-object @
var{typename
}[,@
var{prop1
}=@
var{value1
},...]
2976 Create an
new object of type @
var{typename
} setting properties
2977 in the order they are specified
. Note that the
'id'
2978 property must be set
. These objects are placed
in the
2982 HXCOMM This is the last statement
. Insert
new options before
this line
!