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 HXCOMM TODO
: when we are able to change
-help output without breaking
10 HXCOMM libvirt we should update the help options which refer to
-cpu ?
,
11 HXCOMM
-driver ?
, etc to use the preferred
-cpu help etc instead
.
13 DEFHEADING(Standard options
:)
18 DEF("help", 0, QEMU_OPTION_h
,
19 "-h or -help display this help and exit\n", QEMU_ARCH_ALL
)
26 DEF("version", 0, QEMU_OPTION_version
,
27 "-version display version information and exit\n", QEMU_ARCH_ALL
)
31 Display version information and exit
34 DEF("machine", HAS_ARG
, QEMU_OPTION_machine
, \
35 "-machine [type=]name[,prop[=value][,...]]\n"
36 " selects emulated machine (-machine ? for list)\n"
37 " property accel=accel1[:accel2[:...]] selects accelerator\n"
38 " supported accelerators are kvm, xen, tcg (default: tcg)\n"
39 " kernel_irqchip=on|off controls accelerated irqchip support\n"
40 " kvm_shadow_mem=size of KVM shadow MMU\n"
41 " dump-guest-core=on|off include guest memory in a core dump (default=on)\n",
44 @item
-machine
[type
=]@
var{name
}[,prop
=@
var{value
}[,...]]
46 Select the emulated machine by @
var{name
}. Use @code
{-machine ?
} to list
47 available machines
. Supported machine properties are
:
49 @item accel
=@
var{accels1
}[:@
var{accels2
}[:...]]
50 This is used to enable an accelerator
. Depending on the target architecture
,
51 kvm
, xen
, or tcg can be available
. By
default, tcg is used
. If there is more
52 than one accelerator specified
, the next one is used
if the previous one fails
54 @item kernel_irqchip
=on|off
55 Enables
in-kernel irqchip support
for the chosen accelerator when available
.
56 @item kvm_shadow_mem
=size
57 Defines the size of the KVM shadow MMU
.
58 @item dump
-guest
-core
=on|off
59 Include guest memory
in a core dump
. The
default is on
.
63 HXCOMM Deprecated by
-machine
64 DEF("M", HAS_ARG
, QEMU_OPTION_M
, "", QEMU_ARCH_ALL
)
66 DEF("cpu", HAS_ARG
, QEMU_OPTION_cpu
,
67 "-cpu cpu select CPU (-cpu ? for list)\n", QEMU_ARCH_ALL
)
69 @item
-cpu @
var{model
}
71 Select CPU
model (-cpu ?
for list and additional feature selection
)
74 DEF("smp", HAS_ARG
, QEMU_OPTION_smp
,
75 "-smp n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
76 " set the number of CPUs to 'n' [default=1]\n"
77 " maxcpus= maximum number of total cpus, including\n"
78 " offline CPUs for hotplug, etc\n"
79 " cores= number of CPU cores on one socket\n"
80 " threads= number of threads on one CPU core\n"
81 " sockets= number of discrete sockets in the system\n",
84 @item
-smp @
var{n
}[,cores
=@
var{cores
}][,threads
=@
var{threads
}][,sockets
=@
var{sockets
}][,maxcpus
=@
var{maxcpus
}]
86 Simulate an SMP system with @
var{n
} CPUs
. On the PC target
, up to
255
87 CPUs are supported
. On Sparc32 target
, Linux limits the number of usable CPUs
89 For the PC target
, the number of @
var{cores
} per socket
, the number
90 of @
var{threads
} per cores and the total number of @
var{sockets
} can be
91 specified
. Missing values will be computed
. If any on the three values is
92 given
, the total number of CPUs @
var{n
} can be omitted
. @
var{maxcpus
}
93 specifies the maximum number of hotpluggable CPUs
.
96 DEF("numa", HAS_ARG
, QEMU_OPTION_numa
,
97 "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL
)
99 @item
-numa @
var{opts
}
101 Simulate a multi node NUMA system
. If mem and cpus are omitted
, resources
105 DEF("fda", HAS_ARG
, QEMU_OPTION_fda
,
106 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL
)
107 DEF("fdb", HAS_ARG
, QEMU_OPTION_fdb
, "", QEMU_ARCH_ALL
)
109 @item
-fda @
var{file
}
110 @item
-fdb @
var{file
}
113 Use @
var{file
} as floppy disk
0/1 image (@pxref
{disk_images
}). You can
114 use the host floppy by
using @file
{/dev
/fd0
} as
filename (@pxref
{host_drives
}).
117 DEF("hda", HAS_ARG
, QEMU_OPTION_hda
,
118 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL
)
119 DEF("hdb", HAS_ARG
, QEMU_OPTION_hdb
, "", QEMU_ARCH_ALL
)
120 DEF("hdc", HAS_ARG
, QEMU_OPTION_hdc
,
121 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL
)
122 DEF("hdd", HAS_ARG
, QEMU_OPTION_hdd
, "", QEMU_ARCH_ALL
)
124 @item
-hda @
var{file
}
125 @item
-hdb @
var{file
}
126 @item
-hdc @
var{file
}
127 @item
-hdd @
var{file
}
132 Use @
var{file
} as hard disk
0, 1, 2 or
3 image (@pxref
{disk_images
}).
135 DEF("cdrom", HAS_ARG
, QEMU_OPTION_cdrom
,
136 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
139 @item
-cdrom @
var{file
}
141 Use @
var{file
} as CD
-ROM
image (you cannot use @option
{-hdc
} and
142 @option
{-cdrom
} at the same time
). You can use the host CD
-ROM by
143 using @file
{/dev
/cdrom
} as
filename (@pxref
{host_drives
}).
146 DEF("drive", HAS_ARG
, QEMU_OPTION_drive
,
147 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
148 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
149 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
150 " [,serial=s][,addr=A][,id=name][,aio=threads|native]\n"
151 " [,readonly=on|off][,copy-on-read=on|off]\n"
152 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]][[,iops=i]|[[,iops_rd=r][,iops_wr=w]]\n"
153 " use 'file' as a drive image\n", QEMU_ARCH_ALL
)
155 @item
-drive @
var{option
}[,@
var{option
}[,@
var{option
}[,...]]]
158 Define a
new drive
. Valid options are
:
161 @item file
=@
var{file
}
162 This option defines which disk
image (@pxref
{disk_images
}) to use with
163 this drive
. If the filename contains comma
, you must double it
164 (for instance
, "file=my,,file" to use file
"my,file").
166 Special files such as iSCSI devices can be specified
using protocol
167 specific URLs
. See the section
for "Device URL Syntax" for more information
.
168 @item
if=@
var{interface}
169 This option defines on which type on
interface the drive is connected
.
170 Available types are
: ide
, scsi
, sd
, mtd
, floppy
, pflash
, virtio
.
171 @item bus
=@
var{bus
},unit
=@
var{unit
}
172 These options define where is connected the drive by defining the bus number and
174 @item index
=@
var{index
}
175 This option defines where is connected the drive by
using an index
in the list
176 of available connectors of a given
interface type
.
177 @item media
=@
var{media
}
178 This option defines the type of the media
: disk or cdrom
.
179 @item cyls
=@
var{c
},heads
=@
var{h
},secs
=@
var{s
}[,trans
=@
var{t
}]
180 These options have the same definition as they have
in @option
{-hdachs
}.
181 @item snapshot
=@
var{snapshot
}
182 @
var{snapshot
} is
"on" or
"off" and allows to enable snapshot
for given
drive (see @option
{-snapshot
}).
183 @item cache
=@
var{cache
}
184 @
var{cache
} is
"none", "writeback", "unsafe", "directsync" or
"writethrough" and controls how the host cache is used to access block data
.
186 @
var{aio
} is
"threads", or
"native" and selects between pthread based disk I
/O and native Linux AIO
.
187 @item format
=@
var{format
}
188 Specify which disk @
var{format
} will be used rather than detecting
189 the format
. Can be used to specifiy format
=raw to avoid interpreting
190 an untrusted format header
.
191 @item serial
=@
var{serial
}
192 This option specifies the serial number to assign to the device
.
193 @item addr
=@
var{addr
}
194 Specify the controller
's PCI address (if=virtio only).
195 @item werror=@var{action},rerror=@var{action}
196 Specify which @var{action} to take on write and read errors. Valid actions are:
197 "ignore" (ignore the error and try to continue), "stop" (pause QEMU),
198 "report" (report the error to the guest), "enospc" (pause QEMU only if the
199 host disk is full; report the error to the guest otherwise).
200 The default setting is @option{werror=enospc} and @option{rerror=report}.
202 Open drive @option{file} as read-only. Guest write attempts will fail.
203 @item copy-on-read=@var{copy-on-read}
204 @var{copy-on-read} is "on" or "off" and enables whether to copy read backing
205 file sectors into the image file.
208 By default, writethrough caching is used for all block device. This means that
209 the host page cache will be used to read and write data but write notification
210 will be sent to the guest only when the data has been reported as written by
211 the storage subsystem.
213 Writeback caching will report data writes as completed as soon as the data is
214 present in the host page cache. This is safe as long as you trust your host.
215 If your host crashes or loses power, then the guest may experience data
218 The host page cache can be avoided entirely with @option{cache=none}. This will
219 attempt to do disk IO directly to the guests memory. QEMU may still perform
220 an internal copy of the data.
222 The host page cache can be avoided while only sending write notifications to
223 the guest when the data has been reported as written by the storage subsystem
224 using @option{cache=directsync}.
226 Some block drivers perform badly with @option{cache=writethrough}, most notably,
227 qcow2. If performance is more important than correctness,
228 @option{cache=writeback} should be used with qcow2.
230 In case you don't care about data integrity over host failures
, use
231 cache
=unsafe
. This option tells QEMU that it
never needs to write any data
232 to the disk but can instead keeps things
in cache
. If anything goes wrong
,
233 like your host losing power
, the disk storage getting disconnected accidentally
,
234 etc
. you
're image will most probably be rendered unusable. When using
235 the @option{-snapshot} option, unsafe caching is always used.
237 Copy-on-read avoids accessing the same backing file sectors repeatedly and is
238 useful when the backing file is over a slow network. By default copy-on-read
241 Instead of @option{-cdrom} you can use:
243 qemu-system-i386 -drive file=file,index=2,media=cdrom
246 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
249 qemu-system-i386 -drive file=file,index=0,media=disk
250 qemu-system-i386 -drive file=file,index=1,media=disk
251 qemu-system-i386 -drive file=file,index=2,media=disk
252 qemu-system-i386 -drive file=file,index=3,media=disk
255 You can connect a CDROM to the slave of ide0:
257 qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
260 If you don't specify the
"file=" argument
, you define an empty drive
:
262 qemu
-system
-i386
-drive
if=ide
,index
=1,media
=cdrom
265 You can connect a SCSI disk with unit ID
6 on the bus #
0:
267 qemu
-system
-i386
-drive file
=file
,if=scsi
,bus
=0,unit
=6
270 Instead of @option
{-fda
}, @option
{-fdb
}, you can use
:
272 qemu
-system
-i386
-drive file
=file
,index
=0,if=floppy
273 qemu
-system
-i386
-drive file
=file
,index
=1,if=floppy
276 By
default, @
var{interface} is
"ide" and @
var{index
} is automatically
279 qemu
-system
-i386
-drive file
=a
-drive file
=b
"
283 qemu-system-i386 -hda a -hdb b
287 DEF("set
", HAS_ARG, QEMU_OPTION_set,
288 "-set group
.id
.arg
=value
\n"
289 " set
<arg
> parameter
for item
<id
> of type
<group
>\n"
290 " i
.e
. -set drive
.$id
.file
=/path
/to
/image
\n", QEMU_ARCH_ALL)
297 DEF("global
", HAS_ARG, QEMU_OPTION_global,
298 "-global driver
.prop
=value
\n"
299 " set a global
default for a driver property
\n",
302 @item -global @var{driver}.@var{prop}=@var{value}
304 Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.:
307 qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk
310 In particular, you can use this to set driver properties for devices which are
311 created automatically by the machine model. To create a device which is not
312 created automatically and set properties on it, use -@option{device}.
315 DEF("mtdblock
", HAS_ARG, QEMU_OPTION_mtdblock,
316 "-mtdblock file use
'file' as on
-board Flash memory image
\n",
319 @item -mtdblock @var{file}
321 Use @var{file} as on-board Flash memory image.
324 DEF("sd
", HAS_ARG, QEMU_OPTION_sd,
325 "-sd file use
'file' as SecureDigital card image
\n", QEMU_ARCH_ALL)
329 Use @var{file} as SecureDigital card image.
332 DEF("pflash
", HAS_ARG, QEMU_OPTION_pflash,
333 "-pflash file use
'file' as a parallel flash image
\n", QEMU_ARCH_ALL)
335 @item -pflash @var{file}
337 Use @var{file} as a parallel flash image.
340 DEF("boot
", HAS_ARG, QEMU_OPTION_boot,
341 "-boot
[order
=drives
][,once
=drives
][,menu
=on|off
]\n"
342 " [,splash
=sp_name
][,splash
-time
=sp_time
]\n"
343 " 'drives': floppy (a
), hard
disk (c
), CD
-ROM (d
), network (n
)\n"
344 " 'sp_name': the file
's name that would be passed to bios as logo picture, if menu=on\n"
345 " 'sp_time
': the period that splash picture last if menu=on, unit is ms\n",
348 @item -boot [order=@var{drives}][,once=@var{drives}][,menu=on|off][,splash=@var{sp_name}][,splash-time=@var{sp_time}]
350 Specify boot order @var{drives} as a string of drive letters. Valid
351 drive letters depend on the target achitecture. The x86 PC uses: a, b
352 (floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
353 from network adapter 1-4), hard disk boot is the default. To apply a
354 particular boot order only on the first startup, specify it via
357 Interactive boot menus/prompts can be enabled via @option{menu=on} as far
358 as firmware/BIOS supports them. The default is non-interactive boot.
360 A splash picture could be passed to bios, enabling user to show it as logo,
361 when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
362 supports them. Currently Seabios for X86 system support it.
363 limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
364 format(true color). The resolution should be supported by the SVGA mode, so
365 the recommended is 320x240, 640x480, 800x640.
368 # try to boot from network first, then from hard disk
369 qemu-system-i386 -boot order=nc
370 # boot from CD-ROM first, switch back to default order after reboot
371 qemu-system-i386 -boot once=d
372 # boot with a splash picture for 5 seconds.
373 qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
376 Note: The legacy format '-boot @
var{drives
}' is still supported but its
377 use is discouraged as it may be removed from future versions.
380 DEF("snapshot", 0, QEMU_OPTION_snapshot,
381 "-snapshot write to temporary files instead of disk image files\n",
386 Write to temporary files instead of disk image files. In this case,
387 the raw disk image you use is not written back. You can however force
388 the write back by pressing @key{C-a s} (@pxref{disk_images}).
391 DEF("m", HAS_ARG, QEMU_OPTION_m,
392 "-m megs set virtual RAM size to megs MB [default="
393 stringify(DEFAULT_RAM_SIZE) "]\n", QEMU_ARCH_ALL)
397 Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally,
398 a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or
399 gigabytes respectively.
402 DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
403 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
405 @item -mem-path @var{path}
406 Allocate guest RAM from a temporarily created file in @var{path}.
410 DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
411 "-mem-prealloc preallocate guest memory (use with -mem-path)\n",
415 Preallocate memory when using -mem-path.
419 DEF("k", HAS_ARG, QEMU_OPTION_k,
420 "-k language use keyboard layout (for example 'fr
' for French)\n",
423 @item -k @var{language}
425 Use keyboard layout @var{language} (for example @code{fr} for
426 French). This option is only needed where it is not easy to get raw PC
427 keycodes (e.g. on Macs, with some X11 servers or with a VNC
428 display). You don't normally need to use it on PC
/Linux or PC
/Windows
431 The available layouts are
:
433 ar de
-ch es fo fr
-ca hu ja mk no pt
-br sv
434 da en
-gb et fr fr
-ch is lt nl pl ru th
435 de en
-us fi fr
-be hr it lv nl
-be pt sl tr
438 The
default is @code
{en
-us
}.
442 DEF("audio-help", 0, QEMU_OPTION_audio_help
,
443 "-audio-help print list of audio drivers and their options\n",
448 Will show the audio subsystem help
: list of drivers
, tunable
452 DEF("soundhw", HAS_ARG
, QEMU_OPTION_soundhw
,
453 "-soundhw c1,... enable audio support\n"
454 " and only specified sound cards (comma separated list)\n"
455 " use -soundhw ? to get the list of supported cards\n"
456 " use -soundhw all to enable all of them\n", QEMU_ARCH_ALL
)
458 @item
-soundhw @
var{card1
}[,@
var{card2
},...] or
-soundhw all
460 Enable audio and selected sound hardware
. Use ? to print all
461 available sound hardware
.
464 qemu
-system
-i386
-soundhw sb16
,adlib disk
.img
465 qemu
-system
-i386
-soundhw es1370 disk
.img
466 qemu
-system
-i386
-soundhw ac97 disk
.img
467 qemu
-system
-i386
-soundhw hda disk
.img
468 qemu
-system
-i386
-soundhw all disk
.img
469 qemu
-system
-i386
-soundhw ?
472 Note that Linux
's i810_audio OSS kernel (for AC97) module might
473 require manually specifying clocking.
476 modprobe i810_audio clocking=48000
480 DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
481 "-balloon none disable balloon device\n"
482 "-balloon virtio[,addr=str]\n"
483 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL)
487 Disable balloon device.
488 @item -balloon virtio[,addr=@var{addr}]
489 Enable virtio balloon device (default), optionally with PCI address
497 DEF("usb", 0, QEMU_OPTION_usb,
498 "-usb enable the USB driver (will be the default soon)\n",
506 Enable the USB driver (will be the default soon)
509 DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
510 "-usbdevice name add the host or guest USB device 'name
'\n",
514 @item -usbdevice @var{devname}
516 Add the USB device @var{devname}. @xref{usb_devices}.
521 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
524 Pointer device that uses absolute coordinates (like a touchscreen). This
525 means QEMU is able to report the mouse position without having to grab the
526 mouse. Also overrides the PS/2 mouse emulation when activated.
528 @item disk:[format=@var{format}]:@var{file}
529 Mass storage device based on file. The optional @var{format} argument
530 will be used rather than detecting the format. Can be used to specifiy
531 @code{format=raw} to avoid interpreting an untrusted format header.
533 @item host:@var{bus}.@var{addr}
534 Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
536 @item host:@var{vendor_id}:@var{product_id}
537 Pass through the host device identified by @var{vendor_id}:@var{product_id}
540 @item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
541 Serial converter to host character device @var{dev}, see @code{-serial} for the
545 Braille device. This will use BrlAPI to display the braille output on a real
548 @item net:@var{options}
549 Network adapter that supports CDC ethernet and RNDIS protocols.
554 DEF("device", HAS_ARG, QEMU_OPTION_device,
555 "-device driver[,prop[=value][,...]]\n"
556 " add device (based on driver)\n"
557 " prop=value,... sets driver properties\n"
558 " use -device ? to print all possible drivers\n"
559 " use -device driver,? to print all possible properties\n",
562 @item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
564 Add device @var{driver}. @var{prop}=@var{value} sets driver
565 properties. Valid properties depend on the driver. To get help on
566 possible drivers and properties, use @code{-device ?} and
567 @code{-device @var{driver},?}.
572 DEFHEADING(File system options:)
574 DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
575 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
576 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
581 @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}]
583 Define a new file system device. Valid options are:
586 This option specifies the fs driver backend to use.
587 Currently "local", "handle" and "proxy" file system drivers are supported.
589 Specifies identifier for this device
590 @item path=@var{path}
591 Specifies the export path for the file system device. Files under
592 this path will be available to the 9p client on the guest.
593 @item security_model=@var{security_model}
594 Specifies the security model to be used for this export path.
595 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
596 In "passthrough" security model, files are stored using the same
597 credentials as they are created on the guest. This requires QEMU
598 to run as root. In "mapped-xattr" security model, some of the file
599 attributes like uid, gid, mode bits and link target are stored as
600 file attributes. For "mapped-file" these attributes are stored in the
601 hidden .virtfs_metadata directory. Directories exported by this security model cannot
602 interact with other unix tools. "none" security model is same as
603 passthrough except the sever won't report failures
if it fails to
604 set file attributes like ownership
. Security model is mandatory
605 only
for local fsdriver
. Other
fsdrivers (like handle
, proxy
) don
't take
606 security model as a parameter.
607 @item writeout=@var{writeout}
608 This is an optional argument. The only supported value is "immediate".
609 This means that host page cache will be used to read and write data but
610 write notification will be sent to the guest only when the data has been
611 reported as written by the storage subsystem.
613 Enables exporting 9p share as a readonly mount for guests. By default
614 read-write access is given.
615 @item socket=@var{socket}
616 Enables proxy filesystem driver to use passed socket file for communicating
617 with virtfs-proxy-helper
618 @item sock_fd=@var{sock_fd}
619 Enables proxy filesystem driver to use passed socket descriptor for
620 communicating with virtfs-proxy-helper. Usually a helper like libvirt
621 will create socketpair and pass one of the fds as sock_fd
624 -fsdev option is used along with -device driver "virtio-9p-pci".
625 @item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
626 Options for virtio-9p-pci driver are:
629 Specifies the id value specified along with -fsdev option
630 @item mount_tag=@var{mount_tag}
631 Specifies the tag name to be used by the guest to mount this export point
638 DEFHEADING(Virtual File system pass-through options:)
640 DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
641 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
642 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
647 @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}]
650 The general form of a Virtual File system pass-through options are:
653 This option specifies the fs driver backend to use.
654 Currently "local", "handle" and "proxy" file system drivers are supported.
656 Specifies identifier for this device
657 @item path=@var{path}
658 Specifies the export path for the file system device. Files under
659 this path will be available to the 9p client on the guest.
660 @item security_model=@var{security_model}
661 Specifies the security model to be used for this export path.
662 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
663 In "passthrough" security model, files are stored using the same
664 credentials as they are created on the guest. This requires QEMU
665 to run as root. In "mapped-xattr" security model, some of the file
666 attributes like uid, gid, mode bits and link target are stored as
667 file attributes. For "mapped-file" these attributes are stored in the
668 hidden .virtfs_metadata directory. Directories exported by this security model cannot
669 interact with other unix tools. "none" security model is same as
670 passthrough except the sever won't report failures
if it fails to
671 set file attributes like ownership
. Security model is mandatory only
672 for local fsdriver
. Other
fsdrivers (like handle
, proxy
) don
't take security
673 model as a parameter.
674 @item writeout=@var{writeout}
675 This is an optional argument. The only supported value is "immediate".
676 This means that host page cache will be used to read and write data but
677 write notification will be sent to the guest only when the data has been
678 reported as written by the storage subsystem.
680 Enables exporting 9p share as a readonly mount for guests. By default
681 read-write access is given.
682 @item socket=@var{socket}
683 Enables proxy filesystem driver to use passed socket file for
684 communicating with virtfs-proxy-helper. Usually a helper like libvirt
685 will create socketpair and pass one of the fds as sock_fd
687 Enables proxy filesystem driver to use passed 'sock_fd
' as the socket
688 descriptor for interfacing with virtfs-proxy-helper
692 DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
693 "-virtfs_synth Create synthetic file system image\n",
697 @findex -virtfs_synth
698 Create synthetic file system image
703 DEF("name", HAS_ARG, QEMU_OPTION_name,
704 "-name string1[,process=string2]\n"
705 " set the name of the guest\n"
706 " string1 sets the window title and string2 the process name (on Linux)\n",
709 @item -name @var{name}
711 Sets the @var{name} of the guest.
712 This name will be displayed in the SDL window caption.
713 The @var{name} will also be used for the VNC server.
714 Also optionally set the top visible process name in Linux.
717 DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
718 "-uuid %08x-%04x-%04x-%04x-%012x\n"
719 " specify machine UUID\n", QEMU_ARCH_ALL)
721 @item -uuid @var{uuid}
732 DEFHEADING(Display options:)
738 DEF("display", HAS_ARG, QEMU_OPTION_display,
739 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
740 " [,window_close=on|off]|curses|none|\n"
741 " vnc=<display>[,<optargs>]\n"
742 " select display type\n", QEMU_ARCH_ALL)
744 @item -display @var{type}
746 Select type of display to use. This option is a replacement for the
747 old style -sdl/-curses/... options. Valid values for @var{type} are
750 Display video output via SDL (usually in a separate graphics
751 window; see the SDL documentation for other possibilities).
753 Display video output via curses. For graphics device models which
754 support a text mode, QEMU can display this output using a
755 curses/ncurses interface. Nothing is displayed when the graphics
756 device is in graphical mode or if the graphics device does not support
757 a text mode. Generally only the VGA device models support text mode.
759 Do not display video output. The guest will still see an emulated
760 graphics card, but its output will not be displayed to the QEMU
761 user. This option differs from the -nographic option in that it
762 only affects what is done with video output; -nographic also changes
763 the destination of the serial and parallel port data.
765 Start a VNC server on display <arg>
769 DEF("nographic", 0, QEMU_OPTION_nographic,
770 "-nographic disable graphical output and redirect serial I/Os to console\n",
775 Normally, QEMU uses SDL to display the VGA output. With this option,
776 you can totally disable graphical output so that QEMU is a simple
777 command line application. The emulated serial port is redirected on
778 the console. Therefore, you can still use QEMU to debug a Linux kernel
779 with a serial console.
782 DEF("curses", 0, QEMU_OPTION_curses,
783 "-curses use a curses/ncurses interface instead of SDL\n",
788 Normally, QEMU uses SDL to display the VGA output. With this option,
789 QEMU can display the VGA output when in text mode using a
790 curses/ncurses interface. Nothing is displayed in graphical mode.
793 DEF("no-frame", 0, QEMU_OPTION_no_frame,
794 "-no-frame open SDL window without a frame and window decorations\n",
799 Do not use decorations for SDL windows and start them using the whole
800 available screen space. This makes the using QEMU in a dedicated desktop
801 workspace more convenient.
804 DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
805 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
810 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
811 affects the special keys (for fullscreen, monitor-mode switching, etc).
814 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
815 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
820 Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
821 affects the special keys (for fullscreen, monitor-mode switching, etc).
824 DEF("no-quit", 0, QEMU_OPTION_no_quit,
825 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL)
829 Disable SDL window close capability.
832 DEF("sdl", 0, QEMU_OPTION_sdl,
833 "-sdl enable SDL\n", QEMU_ARCH_ALL)
840 DEF("spice", HAS_ARG, QEMU_OPTION_spice,
841 "-spice <args> enable spice\n", QEMU_ARCH_ALL)
843 @item -spice @var{option}[,@var{option}[,...]]
845 Enable the spice remote desktop protocol. Valid options are
850 Set the TCP port spice is listening on for plaintext channels.
853 Set the IP address spice is listening on. Default is any address.
857 Force using the specified IP version.
859 @item password=<secret>
860 Set the password you need to authenticate.
863 Require that the client use SASL to authenticate with the spice.
864 The exact choice of authentication method used is controlled from the
865 system / user's SASL configuration file
for the
'qemu' service
. This
866 is typically found
in /etc
/sasl2
/qemu
.conf
. If running QEMU as an
867 unprivileged user
, an environment variable SASL_CONF_PATH can be used
868 to make it search alternate locations
for the service config
.
869 While some SASL auth methods can also provide data
encryption (eg GSSAPI
),
870 it is recommended that SASL always be combined with the
'tls' and
871 'x509' settings to enable use of SSL and server certificates
. This
872 ensures a data encryption preventing compromise of authentication
875 @item disable
-ticketing
876 Allow client connects without authentication
.
878 @item disable
-copy
-paste
879 Disable copy paste between the client and the guest
.
882 Set the TCP port spice is listening on
for encrypted channels
.
885 Set the x509 file directory
. Expects same filenames as
-vnc $display
,x509
=$dir
887 @item x509
-key
-file
=<file
>
888 @item x509
-key
-password
=<file
>
889 @item x509
-cert
-file
=<file
>
890 @item x509
-cacert
-file
=<file
>
891 @item x509
-dh
-key
-file
=<file
>
892 The x509 file names can also be configured individually
.
894 @item tls
-ciphers
=<list
>
895 Specify which ciphers to use
.
897 @item tls
-channel
=[main|display|cursor|inputs|record|playback
]
898 @item plaintext
-channel
=[main|display|cursor|inputs|record|playback
]
899 Force specific channel to be used with or without TLS encryption
. The
900 options can be specified multiple times to configure multiple
901 channels
. The special name
"default" can be used to set the
default
902 mode
. For channels which are not explicitly forced into one mode the
903 spice client is allowed to pick tls
/plaintext as he pleases
.
905 @item image
-compression
=[auto_glz|auto_lz|quic|glz|lz|off
]
906 Configure image
compression (lossless
).
909 @item jpeg
-wan
-compression
=[auto|
never|always
]
910 @item zlib
-glz
-wan
-compression
=[auto|
never|always
]
911 Configure wan image
compression (lossy
for slow links
).
914 @item streaming
-video
=[off|all|filter
]
915 Configure video stream detection
. Default is filter
.
917 @item agent
-mouse
=[on|off
]
918 Enable
/disable passing mouse events via vdagent
. Default is on
.
920 @item playback
-compression
=[on|off
]
921 Enable
/disable audio stream
compression (using celt
0.5.1). Default is on
.
926 DEF("portrait", 0, QEMU_OPTION_portrait
,
927 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
932 Rotate graphical output
90 deg
left (only PXA LCD
).
935 DEF("rotate", HAS_ARG
, QEMU_OPTION_rotate
,
936 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
941 Rotate graphical output some deg
left (only PXA LCD
).
944 DEF("vga", HAS_ARG
, QEMU_OPTION_vga
,
945 "-vga [std|cirrus|vmware|qxl|xenfb|none]\n"
946 " select video card type\n", QEMU_ARCH_ALL
)
948 @item
-vga @
var{type
}[,@
var{prop
}=@
var{value
}[,...]]
950 Select type of VGA card to emulate
. Valid values
for @
var{type
} are
953 Cirrus Logic GD5446 Video card
. All Windows versions starting from
954 Windows
95 should recognize and use
this graphic card
. For optimal
955 performances
, use
16 bit color depth
in the guest and the host OS
.
956 (This one is the
default)
958 Standard VGA card with Bochs VBE extensions
. If your guest OS
959 supports the VESA
2.0 VBE
extensions (e
.g
. Windows XP
) and
if you want
960 to use high resolution
modes (>= 1280x1024x16
) then you should use
963 VMWare SVGA
-II compatible adapter
. Use it
if you have sufficiently
964 recent XFree86
/XOrg server or Windows guest with a driver
for this
967 QXL paravirtual graphic card
. It is VGA
compatible (including VESA
968 2.0 VBE support
). Works best with qxl guest drivers installed though
.
969 Recommended choice when
using the spice protocol
.
973 Valid optional properties are
975 @item retrace
=dumb|precise
976 Select
dumb (default) or precise VGA retrace logic
, useful
for some
981 DEF("full-screen", 0, QEMU_OPTION_full_screen
,
982 "-full-screen start in full screen\n", QEMU_ARCH_ALL
)
986 Start
in full screen
.
989 DEF("g", 1, QEMU_OPTION_g
,
990 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
991 QEMU_ARCH_PPC | QEMU_ARCH_SPARC
)
993 @item
-g @
var{width
}x@
var{height
}[x@
var{depth
}]
995 Set the initial graphical resolution and
depth (PPC
, SPARC only
).
998 DEF("vnc", HAS_ARG
, QEMU_OPTION_vnc
,
999 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL
)
1001 @item
-vnc @
var{display
}[,@
var{option
}[,@
var{option
}[,...]]]
1003 Normally
, QEMU uses SDL to display the VGA output
. With
this option
,
1004 you can have QEMU listen on VNC display @
var{display
} and redirect the VGA
1005 display over the VNC session
. It is very useful to enable the usb
1006 tablet device when
using this option (option @option
{-usbdevice
1007 tablet
}). When
using the VNC display
, you must use the @option
{-k
}
1008 parameter to set the keyboard layout
if you are not
using en
-us
. Valid
1009 syntax
for the @
var{display
} is
1013 @item @
var{host
}:@
var{d
}
1015 TCP connections will only be allowed from @
var{host
} on display @
var{d
}.
1016 By convention the TCP port is
5900+@
var{d
}. Optionally
, @
var{host
} can
1017 be omitted
in which
case the server will accept connections from any host
.
1019 @item unix
:@
var{path
}
1021 Connections will be allowed over UNIX domain sockets where @
var{path
} is the
1022 location of a unix socket to listen
for connections on
.
1026 VNC is initialized but not started
. The monitor @code
{change
} command
1027 can be used to later start the VNC server
.
1031 Following the @
var{display
} value there may be one or more @
var{option
} flags
1032 separated by commas
. Valid options are
1038 Connect to a listening VNC client via a ``reverse
'' connection
. The
1039 client is specified by the @
var{display
}. For reverse network
1040 connections (@
var{host
}:@
var{d
},@code
{reverse
}), the @
var{d
} argument
1041 is a TCP port number
, not a display number
.
1045 Require that password based authentication is used
for client connections
.
1047 The password must be set separately
using the @code
{set_password
} command
in
1048 the @ref
{pcsys_monitor
}. The syntax to change your password is
:
1049 @code
{set_password
<protocol
> <password
>} where
<protocol
> could be either
1052 If you would like to change
<protocol
> password expiration
, you should use
1053 @code
{expire_password
<protocol
> <expiration
-time
>} where expiration time could
1054 be one of the following options
: now
, never, +seconds or UNIX time of
1055 expiration
, e
.g
. +60 to make password expire
in 60 seconds
, or
1335196800
1056 to make password expire on
"Mon Apr 23 12:00:00 EDT 2012" (UNIX time
for this
1059 You can also use keywords
"now" or
"never" for the expiration time to
1060 allow
<protocol
> password to expire immediately or
never expire
.
1064 Require that client use TLS when communicating with the VNC server
. This
1065 uses anonymous TLS credentials so is susceptible to a man
-in-the
-middle
1066 attack
. It is recommended that
this option be combined with either the
1067 @option
{x509
} or @option
{x509verify
} options
.
1069 @item x509
=@
var{/path
/to
/certificate
/dir
}
1071 Valid
if @option
{tls
} is specified
. Require that x509 credentials are used
1072 for negotiating the TLS session
. The server will send its x509 certificate
1073 to the client
. It is recommended that a password be set on the VNC server
1074 to provide authentication of the client when
this is used
. The path following
1075 this option specifies where the x509 certificates are to be loaded from
.
1076 See the @ref
{vnc_security
} section
for details on generating certificates
.
1078 @item x509verify
=@
var{/path
/to
/certificate
/dir
}
1080 Valid
if @option
{tls
} is specified
. Require that x509 credentials are used
1081 for negotiating the TLS session
. The server will send its x509 certificate
1082 to the client
, and request that the client send its own x509 certificate
.
1083 The server will validate the client
's certificate against the CA certificate,
1084 and reject clients when validation fails. If the certificate authority is
1085 trusted, this is a sufficient authentication mechanism. You may still wish
1086 to set a password on the VNC server as a second authentication layer. The
1087 path following this option specifies where the x509 certificates are to
1088 be loaded from. See the @ref{vnc_security} section for details on generating
1093 Require that the client use SASL to authenticate with the VNC server.
1094 The exact choice of authentication method used is controlled from the
1095 system / user's SASL configuration file
for the
'qemu' service
. This
1096 is typically found
in /etc
/sasl2
/qemu
.conf
. If running QEMU as an
1097 unprivileged user
, an environment variable SASL_CONF_PATH can be used
1098 to make it search alternate locations
for the service config
.
1099 While some SASL auth methods can also provide data
encryption (eg GSSAPI
),
1100 it is recommended that SASL always be combined with the
'tls' and
1101 'x509' settings to enable use of SSL and server certificates
. This
1102 ensures a data encryption preventing compromise of authentication
1103 credentials
. See the @ref
{vnc_security
} section
for details on
using
1104 SASL authentication
.
1108 Turn on access control lists
for checking of the x509 client certificate
1109 and SASL party
. For x509 certs
, the ACL check is made against the
1110 certificate
's distinguished name. This is something that looks like
1111 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1112 made against the username, which depending on the SASL plugin, may
1113 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1114 When the @option{acl} flag is set, the initial access list will be
1115 empty, with a @code{deny} policy. Thus no one will be allowed to
1116 use the VNC server until the ACLs have been loaded. This can be
1117 achieved using the @code{acl} monitor command.
1121 Enable lossy compression methods (gradient, JPEG, ...). If this
1122 option is set, VNC client may receive lossy framebuffer updates
1123 depending on its encoding settings. Enabling this option can save
1124 a lot of bandwidth at the expense of quality.
1128 Disable adaptive encodings. Adaptive encodings are enabled by default.
1129 An adaptive encoding will try to detect frequently updated screen regions,
1130 and send updates in these regions using a lossy encoding (like JPEG).
1131 This can be really helpful to save bandwidth when playing videos. Disabling
1132 adaptive encodings allows to restore the original static behavior of encodings
1135 @item share=[allow-exclusive|force-shared|ignore]
1137 Set display sharing policy. 'allow
-exclusive
' allows clients to ask
1138 for exclusive access. As suggested by the rfb spec this is
1139 implemented by dropping other connections. Connecting multiple
1140 clients in parallel requires all clients asking for a shared session
1141 (vncviewer: -shared switch). This is the default. 'force
-shared
'
1142 disables exclusive client access. Useful for shared desktop sessions,
1143 where you don't want someone forgetting specify
-shared disconnect
1144 everybody
else. 'ignore' completely ignores the shared flag and
1145 allows everybody connect unconditionally
. Doesn
't conform to the rfb
1146 spec but is traditional QEMU behavior.
1155 ARCHHEADING(, QEMU_ARCH_I386)
1157 ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1162 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1163 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1168 Use it when installing Windows 2000 to avoid a disk full bug. After
1169 Windows 2000 is installed, you no longer need this option (this option
1170 slows down the IDE transfers).
1173 HXCOMM Deprecated by -rtc
1174 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1176 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1177 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1180 @item -no-fd-bootchk
1181 @findex -no-fd-bootchk
1182 Disable boot signature checking for floppy disks in Bochs BIOS. It may
1183 be needed to boot from old floppy disks.
1184 TODO: check reference to Bochs BIOS.
1187 DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1188 "-no-acpi disable ACPI\n", QEMU_ARCH_I386)
1192 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1193 it if your guest OS complains about ACPI problems (PC target machine
1197 DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1198 "-no-hpet disable HPET\n", QEMU_ARCH_I386)
1202 Disable HPET support.
1205 DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1206 "-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"
1207 " ACPI table description\n", QEMU_ARCH_I386)
1209 @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}]...]
1211 Add ACPI table with specified header fields and context from specified files.
1212 For file=, take whole ACPI table from the specified files, including all
1213 ACPI headers (possible overridden by other options).
1214 For data=, only data
1215 portion of the table is used, all header information is specified in the
1219 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1220 "-smbios file=binary\n"
1221 " load SMBIOS entry from binary file\n"
1222 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1223 " specify SMBIOS type 0 fields\n"
1224 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1225 " [,uuid=uuid][,sku=str][,family=str]\n"
1226 " specify SMBIOS type 1 fields\n", QEMU_ARCH_I386)
1228 @item -smbios file=@var{binary}
1230 Load SMBIOS entry from binary file.
1232 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}]
1234 Specify SMBIOS type 0 fields
1236 @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}]
1237 Specify SMBIOS type 1 fields
1245 DEFHEADING(Network options:)
1250 HXCOMM Legacy slirp options (now moved to -net user):
1252 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1253 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1254 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1256 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1260 DEF("net", HAS_ARG, QEMU_OPTION_net,
1261 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
1262 " create a new Network Interface Card and connect it to VLAN 'n
'\n"
1264 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=on|off]\n"
1265 " [,hostname=host][,dhcpstart=addr][,dns=addr][,tftp=dir][,bootfile=f]\n"
1266 " [,hostfwd=rule][,guestfwd=rule]"
1268 "[,smb=dir[,smbserver=addr]]\n"
1270 " connect the user mode network stack to VLAN 'n
', configure its\n"
1271 " DHCP server and enabled optional services\n"
1274 "-net tap[,vlan=n][,name=str],ifname=name\n"
1275 " connect the host TAP network interface to VLAN 'n
'\n"
1277 "-net tap[,vlan=n][,name=str][,fd=h][,ifname=name][,script=file][,downscript=dfile][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off][,vhostfd=h][,vhostforce=on|off]\n"
1278 " connect the host TAP network interface to VLAN 'n
' \n"
1279 " use network scripts 'file
' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1280 " to configure it and 'dfile
' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1281 " to deconfigure it\n"
1282 " use '[down
]script
=no
' to disable script execution\n"
1283 " use network helper 'helper
' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1285 " use 'fd
=h
' to connect to an already opened TAP interface\n"
1286 " use 'sndbuf
=nbytes
' to limit the size of the send buffer (the\n"
1287 " default is disabled 'sndbuf
=0' to enable flow control set 'sndbuf
=1048576')\n"
1288 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1289 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1290 " use vhost=on to enable experimental in kernel accelerator\n"
1291 " (only has effect for virtio guests which use MSIX)\n"
1292 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1293 " use 'vhostfd
=h
' to connect to an already opened vhost net device\n"
1294 "-net bridge[,vlan=n][,name=str][,br=bridge][,helper=helper]\n"
1295 " connects a host TAP network interface to a host bridge device 'br
'\n"
1296 " (default=" DEFAULT_BRIDGE_INTERFACE ") using the program 'helper
'\n"
1297 " (default=" DEFAULT_BRIDGE_HELPER ")\n"
1299 "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n"
1300 " connect the vlan 'n
' to another VLAN using a socket connection\n"
1301 "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1302 " connect the vlan 'n
' to multicast maddr and port\n"
1303 " use 'localaddr
=addr
' to specify the host address to send packets from\n"
1304 "-net socket[,vlan=n][,name=str][,fd=h][,udp=host:port][,localaddr=host:port]\n"
1305 " connect the vlan 'n
' to another VLAN using an UDP tunnel\n"
1307 "-net vde[,vlan=n][,name=str][,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1308 " connect the vlan 'n
' to port 'n
' of a vde switch running\n"
1309 " on host and listening for incoming connections on 'socketpath
'.\n"
1310 " Use group 'groupname
' and mode 'octalmode
' to change default\n"
1311 " ownership and permissions for communication port.\n"
1313 "-net dump[,vlan=n][,file=f][,len=n]\n"
1314 " dump traffic on vlan 'n
' to file 'f
' (max n bytes per packet)\n"
1315 "-net none use it alone to have zero network devices. If no -net option\n"
1316 " is provided, the default is '-net nic
-net user
'\n", QEMU_ARCH_ALL)
1317 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1327 "socket],id=str[,option][,option][,...]\n", QEMU_ARCH_ALL)
1329 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1331 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1332 = 0 is the default). The NIC is an e1000 by default on the PC
1333 target. Optionally, the MAC address can be changed to @var{mac}, the
1334 device address set to @var{addr} (PCI cards only),
1335 and a @var{name} can be assigned for use in monitor commands.
1336 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1337 that the card should have; this option currently only affects virtio cards; set
1338 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1339 NIC is created. QEMU can emulate several different models of network card.
1340 Valid values for @var{type} are
1341 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1342 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1343 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1344 Not all devices are supported on all targets. Use -net nic,model=?
1345 for a list of available devices for your target.
1347 @item -net user[,@var{option}][,@var{option}][,...]
1348 Use the user mode network stack which requires no administrator
1349 privilege to run. Valid options are:
1353 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1355 @item name=@var{name}
1356 Assign symbolic name for use in monitor commands.
1358 @item net=@var{addr}[/@var{mask}]
1359 Set IP network address the guest will see. Optionally specify the netmask,
1360 either in the form a.b.c.d or as number of valid top-most bits. Default is
1363 @item host=@var{addr}
1364 Specify the guest-visible address of the host. Default is the 2nd IP in the
1365 guest network, i.e. x.x.x.2.
1367 @item restrict=on|off
1368 If this option is enabled, the guest will be isolated, i.e. it will not be
1369 able to contact the host and no guest IP packets will be routed over the host
1370 to the outside. This option does not affect any explicitly set forwarding rules.
1372 @item hostname=@var{name}
1373 Specifies the client hostname reported by the builtin DHCP server.
1375 @item dhcpstart=@var{addr}
1376 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1377 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1379 @item dns=@var{addr}
1380 Specify the guest-visible address of the virtual nameserver. The address must
1381 be different from the host address. Default is the 3rd IP in the guest network,
1384 @item tftp=@var{dir}
1385 When using the user mode network stack, activate a built-in TFTP
1386 server. The files in @var{dir} will be exposed as the root of a TFTP server.
1387 The TFTP client on the guest must be configured in binary mode (use the command
1388 @code{bin} of the Unix TFTP client).
1390 @item bootfile=@var{file}
1391 When using the user mode network stack, broadcast @var{file} as the BOOTP
1392 filename. In conjunction with @option{tftp}, this can be used to network boot
1393 a guest from a local directory.
1395 Example (using pxelinux):
1397 qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1400 @item smb=@var{dir}[,smbserver=@var{addr}]
1401 When using the user mode network stack, activate a built-in SMB
1402 server so that Windows OSes can access to the host files in @file{@var{dir}}
1403 transparently. The IP address of the SMB server can be set to @var{addr}. By
1404 default the 4th IP in the guest network is used, i.e. x.x.x.4.
1406 In the guest Windows OS, the line:
1410 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1411 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1413 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
1415 Note that a SAMBA server must be installed on the host OS.
1416 QEMU was tested successfully with smbd versions from Red Hat 9,
1417 Fedora Core 3 and OpenSUSE 11.x.
1419 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1420 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1421 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1422 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1423 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1424 be bound to a specific host interface. If no connection type is set, TCP is
1425 used. This option can be given multiple times.
1427 For example, to redirect host X11 connection from screen 1 to guest
1428 screen 0, use the following:
1432 qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1433 # this host xterm should open in the guest X11 server
1437 To redirect telnet connections from host port 5555 to telnet port on
1438 the guest, use the following:
1442 qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
1443 telnet localhost 5555
1446 Then when you use on the host @code{telnet localhost 5555}, you
1447 connect to the guest telnet server.
1449 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1450 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
1451 Forward guest TCP connections to the IP address @var{server} on port @var{port}
1452 to the character device @var{dev} or to a program executed by @var{cmd:command}
1453 which gets spawned for each connection. This option can be given multiple times.
1455 You can either use a chardev directly and have that one used throughout QEMU's
1456 lifetime
, like
in the following example
:
1459 # open
10.10.1.1:4321 on bootup
, connect
10.0.2.100:1234 to it whenever
1460 # the guest accesses it
1461 qemu
-net user
,guestfwd
=tcp
:10.0.2.100:1234-tcp
:10.10.1.1:4321 [...]
1464 Or you can execute a command on every TCP connection established by the guest
,
1465 so that QEMU behaves similar to an inetd process
for that virtual server
:
1468 # call
"netcat 10.10.1.1 4321" on every TCP connection to
10.0.2.100:1234
1469 # and connect the TCP stream to its stdin
/stdout
1470 qemu
-net
'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
1475 Note
: Legacy stand
-alone options
-tftp
, -bootp
, -smb and
-redir are still
1476 processed and applied to
-net user
. Mixing them with the
new configuration
1477 syntax gives undefined results
. Their use
for new applications is discouraged
1478 as they will be removed from future versions
.
1480 @item
-net tap
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}][,ifname
=@
var{name
}][,script
=@
var{file
}][,downscript
=@
var{dfile
}][,helper
=@
var{helper
}]
1481 Connect the host TAP network
interface @
var{name
} to VLAN @
var{n
}.
1483 Use the network script @
var{file
} to configure it and the network script
1484 @
var{dfile
} to deconfigure it
. If @
var{name
} is not provided
, the OS
1485 automatically provides one
. The
default network configure script is
1486 @file
{/etc
/qemu
-ifup
} and the
default network deconfigure script is
1487 @file
{/etc
/qemu
-ifdown
}. Use @option
{script
=no
} or @option
{downscript
=no
}
1488 to disable script execution
.
1490 If running QEMU as an unprivileged user
, use the network helper
1491 @
var{helper
} to configure the TAP
interface. The
default network
1492 helper executable is @file
{/usr
/local
/libexec
/qemu
-bridge
-helper
}.
1494 @option
{fd
}=@
var{h
} can be used to specify the handle of an already
1495 opened host TAP
interface.
1500 #launch a QEMU instance with the
default network script
1501 qemu
-system
-i386 linux
.img
-net nic
-net tap
1505 #launch a QEMU instance with two NICs
, each one connected
1507 qemu
-system
-i386 linux
.img \
1508 -net nic
,vlan
=0 -net tap
,vlan
=0,ifname
=tap0 \
1509 -net nic
,vlan
=1 -net tap
,vlan
=1,ifname
=tap1
1513 #launch a QEMU instance with the
default network helper to
1514 #connect a TAP device to bridge br0
1515 qemu
-system
-i386 linux
.img \
1516 -net nic
-net tap
,"helper=/usr/local/libexec/qemu-bridge-helper"
1519 @item
-net bridge
[,vlan
=@
var{n
}][,name
=@
var{name
}][,br
=@
var{bridge
}][,helper
=@
var{helper
}]
1520 Connect a host TAP network
interface to a host bridge device
.
1522 Use the network helper @
var{helper
} to configure the TAP
interface and
1523 attach it to the bridge
. The
default network helper executable is
1524 @file
{/usr
/local
/libexec
/qemu
-bridge
-helper
} and the
default bridge
1525 device is @file
{br0
}.
1530 #launch a QEMU instance with the
default network helper to
1531 #connect a TAP device to bridge br0
1532 qemu
-system
-i386 linux
.img
-net bridge
-net nic
,model
=virtio
1536 #launch a QEMU instance with the
default network helper to
1537 #connect a TAP device to bridge qemubr0
1538 qemu
-system
-i386 linux
.img
-net bridge
,br
=qemubr0
-net nic
,model
=virtio
1541 @item
-net socket
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}] [,listen
=[@
var{host
}]:@
var{port
}][,connect
=@
var{host
}:@
var{port
}]
1543 Connect the VLAN @
var{n
} to a remote VLAN
in another QEMU virtual
1544 machine
using a TCP socket connection
. If @option
{listen
} is
1545 specified
, QEMU waits
for incoming connections on @
var{port
}
1546 (@
var{host
} is optional
). @option
{connect
} is used to connect to
1547 another QEMU instance
using the @option
{listen
} option
. @option
{fd
}=@
var{h
}
1548 specifies an already opened TCP socket
.
1552 # launch a first QEMU instance
1553 qemu
-system
-i386 linux
.img \
1554 -net nic
,macaddr
=52:54:00:12:34:56 \
1555 -net socket
,listen
=:1234
1556 # connect the VLAN
0 of
this instance to the VLAN
0
1557 # of the first instance
1558 qemu
-system
-i386 linux
.img \
1559 -net nic
,macaddr
=52:54:00:12:34:57 \
1560 -net socket
,connect
=127.0.0.1:1234
1563 @item
-net socket
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}][,mcast
=@
var{maddr
}:@
var{port
}[,localaddr
=@
var{addr
}]]
1565 Create a VLAN @
var{n
} shared with another QEMU virtual
1566 machines
using a UDP multicast socket
, effectively making a bus
for
1567 every QEMU with same multicast address @
var{maddr
} and @
var{port
}.
1571 Several QEMU can be running on different hosts and share same
bus (assuming
1572 correct multicast setup
for these hosts
).
1574 mcast support is compatible with User Mode
Linux (argument @option
{eth@
var{N
}=mcast
}), see
1575 @url
{http
://user-mode-linux.sf.net}.
1577 Use @option
{fd
=h
} to specify an already opened UDP multicast socket
.
1582 # launch one QEMU instance
1583 qemu
-system
-i386 linux
.img \
1584 -net nic
,macaddr
=52:54:00:12:34:56 \
1585 -net socket
,mcast
=230.0.0.1:1234
1586 # launch another QEMU instance on same
"bus"
1587 qemu
-system
-i386 linux
.img \
1588 -net nic
,macaddr
=52:54:00:12:34:57 \
1589 -net socket
,mcast
=230.0.0.1:1234
1590 # launch yet another QEMU instance on same
"bus"
1591 qemu
-system
-i386 linux
.img \
1592 -net nic
,macaddr
=52:54:00:12:34:58 \
1593 -net socket
,mcast
=230.0.0.1:1234
1596 Example (User Mode Linux compat
.):
1598 # launch QEMU
instance (note mcast address selected
1600 qemu-system-i386 linux.img \
1601 -net nic,macaddr=52:54:00:12:34:56 \
1602 -net socket,mcast=239.192.168.1:1102
1604 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
1607 Example (send packets from host's
1.2.3.4):
1609 qemu
-system
-i386 linux
.img \
1610 -net nic
,macaddr
=52:54:00:12:34:56 \
1611 -net socket
,mcast
=239.192.168.1:1102,localaddr
=1.2.3.4
1614 @item
-net vde
[,vlan
=@
var{n
}][,name
=@
var{name
}][,sock
=@
var{socketpath
}] [,port
=@
var{n
}][,group
=@
var{groupname
}][,mode
=@
var{octalmode
}]
1615 Connect VLAN @
var{n
} to PORT @
var{n
} of a vde
switch running on host and
1616 listening
for incoming connections on @
var{socketpath
}. Use GROUP @
var{groupname
}
1617 and MODE @
var{octalmode
} to change
default ownership and permissions
for
1618 communication port
. This option is only available
if QEMU has been compiled
1619 with vde support enabled
.
1624 vde_switch
-F
-sock
/tmp
/myswitch
1625 # launch QEMU instance
1626 qemu
-system
-i386 linux
.img
-net nic
-net vde
,sock
=/tmp
/myswitch
1629 @item
-net dump
[,vlan
=@
var{n
}][,file
=@
var{file
}][,len
=@
var{len
}]
1630 Dump network traffic on VLAN @
var{n
} to file @
var{file
} (@file
{qemu
-vlan0
.pcap
} by
default).
1631 At most @
var{len
} bytes (64k by
default) per packet are stored
. The file format is
1632 libpcap
, so it can be analyzed with tools such as tcpdump or Wireshark
.
1635 Indicate that no network devices should be configured
. It is used to
1636 override the
default configuration (@option
{-net nic
-net user
}) which
1637 is activated
if no @option
{-net
} options are provided
.
1644 DEFHEADING(Character device options
:)
1646 DEF("chardev", HAS_ARG
, QEMU_OPTION_chardev
,
1647 "-chardev null,id=id[,mux=on|off]\n"
1648 "-chardev socket,id=id[,host=host],port=host[,to=to][,ipv4][,ipv6][,nodelay]\n"
1649 " [,server][,nowait][,telnet][,mux=on|off] (tcp)\n"
1650 "-chardev socket,id=id,path=path[,server][,nowait][,telnet],[mux=on|off] (unix)\n"
1651 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
1652 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
1653 "-chardev msmouse,id=id[,mux=on|off]\n"
1654 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
1656 "-chardev file,id=id,path=path[,mux=on|off]\n"
1657 "-chardev pipe,id=id,path=path[,mux=on|off]\n"
1659 "-chardev console,id=id[,mux=on|off]\n"
1660 "-chardev serial,id=id,path=path[,mux=on|off]\n"
1662 "-chardev pty,id=id[,mux=on|off]\n"
1663 "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n"
1665 #ifdef CONFIG_BRLAPI
1666 "-chardev braille,id=id[,mux=on|off]\n"
1668 #
if defined(__linux__
) ||
defined(__sun__
) ||
defined(__FreeBSD__
) \
1669 ||
defined(__NetBSD__
) ||
defined(__OpenBSD__
) ||
defined(__DragonFly__
)
1670 "-chardev tty,id=id,path=path[,mux=on|off]\n"
1672 #
if defined(__linux__
) ||
defined(__FreeBSD__
) ||
defined(__DragonFly__
)
1673 "-chardev parport,id=id,path=path[,mux=on|off]\n"
1675 #
if defined(CONFIG_SPICE
)
1676 "-chardev spicevmc,id=id,name=name[,debug=debug]\n"
1683 The general form of a character device option is
:
1686 @item
-chardev @
var{backend
} ,id
=@
var{id
} [,mux
=on|off
] [,@
var{options
}]
1704 The specific backend will determine the applicable options
.
1706 All devices must have an id
, which can be any string up to
127 characters long
.
1707 It is used to uniquely identify
this device
in other command line directives
.
1709 A character device may be used
in multiplexing mode by multiple front
-ends
.
1710 The key sequence of @key
{Control
-a
} and @key
{c
} will rotate the input focus
1711 between attached front
-ends
. Specify @option
{mux
=on
} to enable
this mode
.
1713 Options to each backend are described below
.
1715 @item
-chardev
null ,id
=@
var{id
}
1716 A void device
. This device will not emit any data
, and will drop any data it
1717 receives
. The
null backend does not take any options
.
1719 @item
-chardev socket
,id
=@
var{id
} [@
var{TCP options
} or @
var{unix options
}] [,server
] [,nowait
] [,telnet
]
1721 Create a two
-way stream socket
, which can be either a TCP or a unix socket
. A
1722 unix socket will be created
if @option
{path
} is specified
. Behaviour is
1723 undefined
if TCP options are specified
for a unix socket
.
1725 @option
{server
} specifies that the socket shall be a listening socket
.
1727 @option
{nowait
} specifies that QEMU should not block waiting
for a client to
1728 connect to a listening socket
.
1730 @option
{telnet
} specifies that traffic on the socket should interpret telnet
1733 TCP and unix socket options are given below
:
1737 @item TCP options
: port
=@
var{port
} [,host
=@
var{host
}] [,to
=@
var{to
}] [,ipv4
] [,ipv6
] [,nodelay
]
1739 @option
{host
} for a listening socket specifies the local address to be bound
.
1740 For a connecting socket species the remote host to connect to
. @option
{host
} is
1741 optional
for listening sockets
. If not specified it defaults to @code
{0.0.0.0}.
1743 @option
{port
} for a listening socket specifies the local port to be bound
. For a
1744 connecting socket specifies the port on the remote host to connect to
.
1745 @option
{port
} can be given as either a port number or a service name
.
1746 @option
{port
} is required
.
1748 @option
{to
} is only relevant to listening sockets
. If it is specified
, and
1749 @option
{port
} cannot be bound
, QEMU will attempt to bind to subsequent ports up
1750 to and including @option
{to
} until it succeeds
. @option
{to
} must be specified
1753 @option
{ipv4
} and @option
{ipv6
} specify that either IPv4 or IPv6 must be used
.
1754 If neither is specified the socket may use either protocol
.
1756 @option
{nodelay
} disables the Nagle algorithm
.
1758 @item unix options
: path
=@
var{path
}
1760 @option
{path
} specifies the local path of the unix socket
. @option
{path
} is
1765 @item
-chardev udp
,id
=@
var{id
} [,host
=@
var{host
}] ,port
=@
var{port
} [,localaddr
=@
var{localaddr
}] [,localport
=@
var{localport
}] [,ipv4
] [,ipv6
]
1767 Sends all traffic from the guest to a remote host over UDP
.
1769 @option
{host
} specifies the remote host to connect to
. If not specified it
1770 defaults to @code
{localhost
}.
1772 @option
{port
} specifies the port on the remote host to connect to
. @option
{port
}
1775 @option
{localaddr
} specifies the local address to bind to
. If not specified it
1776 defaults to @code
{0.0.0.0}.
1778 @option
{localport
} specifies the local port to bind to
. If not specified any
1779 available local port will be used
.
1781 @option
{ipv4
} and @option
{ipv6
} specify that either IPv4 or IPv6 must be used
.
1782 If neither is specified the device may use either protocol
.
1784 @item
-chardev msmouse
,id
=@
var{id
}
1786 Forward QEMU
's emulated msmouse events to the guest. @option{msmouse} does not
1789 @item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
1791 Connect to a QEMU text console. @option{vc} may optionally be given a specific
1794 @option{width} and @option{height} specify the width and height respectively of
1795 the console, in pixels.
1797 @option{cols} and @option{rows} specify that the console be sized to fit a text
1798 console with the given dimensions.
1800 @item -chardev file ,id=@var{id} ,path=@var{path}
1802 Log all traffic received from the guest to a file.
1804 @option{path} specifies the path of the file to be opened. This file will be
1805 created if it does not already exist, and overwritten if it does. @option{path}
1808 @item -chardev pipe ,id=@var{id} ,path=@var{path}
1810 Create a two-way connection to the guest. The behaviour differs slightly between
1811 Windows hosts and other hosts:
1813 On Windows, a single duplex pipe will be created at
1814 @file{\\.pipe\@option{path}}.
1816 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
1817 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
1818 received by the guest. Data written by the guest can be read from
1819 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
1822 @option{path} forms part of the pipe path as described above. @option{path} is
1825 @item -chardev console ,id=@var{id}
1827 Send traffic from the guest to QEMU's standard output
. @option
{console
} does not
1830 @option
{console
} is only available on Windows hosts
.
1832 @item
-chardev serial
,id
=@
var{id
} ,path
=@option
{path
}
1834 Send traffic from the guest to a serial device on the host
.
1837 only available on Windows hosts
.
1839 @option
{path
} specifies the name of the serial device to open
.
1841 @item
-chardev pty
,id
=@
var{id
}
1843 Create a
new pseudo
-terminal on the host and connect to it
. @option
{pty
} does
1844 not take any options
.
1846 @option
{pty
} is not available on Windows hosts
.
1848 @item
-chardev stdio
,id
=@
var{id
} [,signal
=on|off
]
1849 Connect to standard input and standard output of the QEMU process
.
1851 @option
{signal
} controls
if signals are enabled on the terminal
, that includes
1852 exiting QEMU with the key sequence @key
{Control
-c
}. This option is enabled by
1853 default, use @option
{signal
=off
} to disable it
.
1855 @option
{stdio
} is not available on Windows hosts
.
1857 @item
-chardev braille
,id
=@
var{id
}
1859 Connect to a local BrlAPI server
. @option
{braille
} does not take any options
.
1861 @item
-chardev tty
,id
=@
var{id
} ,path
=@
var{path
}
1863 Connect to a local tty device
.
1865 @option
{tty
} is only available on Linux
, Sun
, FreeBSD
, NetBSD
, OpenBSD and
1868 @option
{path
} specifies the path to the tty
. @option
{path
} is required
.
1870 @item
-chardev parport
,id
=@
var{id
} ,path
=@
var{path
}
1872 @option
{parport
} is only available on Linux
, FreeBSD and DragonFlyBSD hosts
.
1874 Connect to a local parallel port
.
1876 @option
{path
} specifies the path to the parallel port device
. @option
{path
} is
1879 @item
-chardev spicevmc
,id
=@
var{id
} ,debug
=@
var{debug
}, name
=@
var{name
}
1881 @option
{spicevmc
} is only available when spice support is built
in.
1883 @option
{debug
} debug level
for spicevmc
1885 @option
{name
} name of spice channel to connect to
1887 Connect to a spice virtual machine channel
, such as vdiport
.
1895 DEFHEADING(Device URL Syntax
:)
1897 In addition to
using normal file images
for the emulated storage devices
,
1898 QEMU can also use networked resources such as iSCSI devices
. These are
1899 specified
using a special URL syntax
.
1903 iSCSI support allows QEMU to access iSCSI resources directly and use as
1904 images
for the guest storage
. Both disk and cdrom images are supported
.
1906 Syntax
for specifying iSCSI LUNs is
1907 ``iscsi
://<target-ip>[:<port>]/<target-iqn>/<lun>''
1909 By
default qemu will use the iSCSI initiator
-name
1910 'iqn.2008-11.org.linux-kvm[:<name>]' but
this can also be set from the command
1911 line or a configuration file
.
1914 Example (without authentication
):
1916 qemu
-system
-i386
-iscsi initiator
-name
=iqn
.2001-04.com
.example
:my
-initiator \
1917 -cdrom iscsi
://192.0.2.1/iqn.2001-04.com.example/2 \
1918 -drive file
=iscsi
://192.0.2.1/iqn.2001-04.com.example/1
1921 Example (CHAP username
/password via URL
):
1923 qemu
-system
-i386
-drive file
=iscsi
://user%password@@192.0.2.1/iqn.2001-04.com.example/1
1926 Example (CHAP username
/password via environment variables
):
1928 LIBISCSI_CHAP_USERNAME
="user" \
1929 LIBISCSI_CHAP_PASSWORD
="password" \
1930 qemu
-system
-i386
-drive file
=iscsi
://192.0.2.1/iqn.2001-04.com.example/1
1933 iSCSI support is an optional feature of QEMU and only available when
1934 compiled and linked against libiscsi
.
1936 DEF("iscsi", HAS_ARG
, QEMU_OPTION_iscsi
,
1937 "-iscsi [user=user][,password=password]\n"
1938 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
1939 " [,initiator-name=iqn]\n"
1940 " iSCSI session parameters\n", QEMU_ARCH_ALL
)
1943 iSCSI parameters such as username and password can also be specified via
1944 a configuration file
. See qemu
-doc
for more information and examples
.
1947 QEMU supports
NBD (Network Block Devices
) both
using TCP protocol as well
1948 as Unix Domain Sockets
.
1950 Syntax
for specifying a NBD device
using TCP
1951 ``nbd
:<server
-ip
>:<port
>[:exportname
=<export
>]''
1953 Syntax
for specifying a NBD device
using Unix Domain Sockets
1954 ``nbd
:unix
:<domain
-socket
>[:exportname
=<export
>]''
1959 qemu
-system
-i386
--drive file
=nbd
:192.0.2.1:30000
1962 Example
for Unix Domain Sockets
1964 qemu
-system
-i386
--drive file
=nbd
:unix
:/tmp
/nbd
-socket
1968 Sheepdog is a distributed storage system
for QEMU
.
1969 QEMU supports
using either local sheepdog devices or remote networked
1972 Syntax
for specifying a sheepdog device
1974 ``sheepdog
:<vdiname
>''
1976 ``sheepdog
:<vdiname
>:<snapid
>''
1978 ``sheepdog
:<vdiname
>:<tag
>''
1980 ``sheepdog
:<host
>:<port
>:<vdiname
>''
1982 ``sheepdog
:<host
>:<port
>:<vdiname
>:<snapid
>''
1984 ``sheepdog
:<host
>:<port
>:<vdiname
>:<tag
>''
1989 qemu
-system
-i386
--drive file
=sheepdog
:192.0.2.1:30000:MyVirtualMachine
1992 See also @url
{http
://http://www.osrg.net/sheepdog/}.
1997 DEFHEADING(Bluetooth(R
) options
:)
1999 DEF("bt", HAS_ARG
, QEMU_OPTION_bt
, \
2000 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \
2001 "-bt hci,host[:id]\n" \
2002 " use host's HCI with the given name\n" \
2003 "-bt hci[,vlan=n]\n" \
2004 " emulate a standard HCI in virtual scatternet 'n'\n" \
2005 "-bt vhci[,vlan=n]\n" \
2006 " add host computer to virtual scatternet 'n' using VHCI\n" \
2007 "-bt device:dev[,vlan=n]\n" \
2008 " emulate a bluetooth device 'dev' in scatternet 'n'\n",
2015 Defines the
function of the corresponding Bluetooth HCI
. -bt options
2016 are matched with the HCIs present
in the chosen machine type
. For
2017 example when emulating a machine with only one HCI built into it
, only
2018 the first @code
{-bt hci
[...]} option is valid and defines the HCI
's
2019 logic. The Transport Layer is decided by the machine type. Currently
2020 the machines @code{n800} and @code{n810} have one HCI and all other
2024 The following three types are recognized:
2028 (default) The corresponding Bluetooth HCI assumes no internal logic
2029 and will not respond to any HCI commands or emit events.
2031 @item -bt hci,host[:@var{id}]
2032 (@code{bluez} only) The corresponding HCI passes commands / events
2033 to / from the physical HCI identified by the name @var{id} (default:
2034 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
2035 capable systems like Linux.
2037 @item -bt hci[,vlan=@var{n}]
2038 Add a virtual, standard HCI that will participate in the Bluetooth
2039 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
2040 VLANs, devices inside a bluetooth network @var{n} can only communicate
2041 with other devices in the same network (scatternet).
2044 @item -bt vhci[,vlan=@var{n}]
2045 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2046 to the host bluetooth stack instead of to the emulated target. This
2047 allows the host and target machines to participate in a common scatternet
2048 and communicate. Requires the Linux @code{vhci} driver installed. Can
2049 be used as following:
2052 qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2055 @item -bt device:@var{dev}[,vlan=@var{n}]
2056 Emulate a bluetooth device @var{dev} and place it in network @var{n}
2057 (default @code{0}). QEMU can only emulate one type of bluetooth devices
2062 Virtual wireless keyboard implementing the HIDP bluetooth profile.
2069 DEFHEADING(Linux/Multiboot boot specific:)
2072 When using these options, you can use a given Linux or Multiboot
2073 kernel without installing it in the disk image. It can be useful
2074 for easier testing of various kernels.
2079 DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
2080 "-kernel bzImage use 'bzImage
' as kernel image\n", QEMU_ARCH_ALL)
2082 @item -kernel @var{bzImage}
2084 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2085 or in multiboot format.
2088 DEF("append", HAS_ARG, QEMU_OPTION_append, \
2089 "-append cmdline use 'cmdline
' as kernel command line\n", QEMU_ARCH_ALL)
2091 @item -append @var{cmdline}
2093 Use @var{cmdline} as kernel command line
2096 DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
2097 "-initrd file use 'file
' as initial ram disk\n", QEMU_ARCH_ALL)
2099 @item -initrd @var{file}
2101 Use @var{file} as initial ram disk.
2103 @item -initrd "@var{file1} arg=foo,@var{file2}"
2105 This syntax is only available with multiboot.
2107 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
2111 DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
2112 "-dtb file use 'file
' as device tree image\n", QEMU_ARCH_ALL)
2114 @item -dtb @var{file}
2116 Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
2126 DEFHEADING(Debug/Expert options:)
2132 DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
2133 "-serial dev redirect the serial port to char device 'dev
'\n",
2136 @item -serial @var{dev}
2138 Redirect the virtual serial port to host character device
2139 @var{dev}. The default device is @code{vc} in graphical mode and
2140 @code{stdio} in non graphical mode.
2142 This option can be used several times to simulate up to 4 serial
2145 Use @code{-serial none} to disable all serial ports.
2147 Available character devices are:
2149 @item vc[:@var{W}x@var{H}]
2150 Virtual console. Optionally, a width and height can be given in pixel with
2154 It is also possible to specify width or height in characters:
2159 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
2161 No device is allocated.
2165 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
2166 parameters are set according to the emulated ones.
2167 @item /dev/parport@var{N}
2168 [Linux only, parallel port only] Use host parallel port
2169 @var{N}. Currently SPP and EPP parallel port features can be used.
2170 @item file:@var{filename}
2171 Write output to @var{filename}. No character can be read.
2173 [Unix only] standard input/output
2174 @item pipe:@var{filename}
2175 name pipe @var{filename}
2177 [Windows only] Use host serial port @var{n}
2178 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
2179 This implements UDP Net Console.
2180 When @var{remote_host} or @var{src_ip} are not specified
2181 they default to @code{0.0.0.0}.
2182 When not using a specified @var{src_port} a random port is automatically chosen.
2184 If you just want a simple readonly console you can use @code{netcat} or
2185 @code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
2186 @code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
2187 will appear in the netconsole session.
2189 If you plan to send characters back via netconsole or you want to stop
2190 and start QEMU a lot of times, you should have QEMU use the same
2191 source port each time by using something like @code{-serial
2192 udp::4555@@:4556} to QEMU. Another approach is to use a patched
2193 version of netcat which can listen to a TCP port and send and receive
2194 characters via udp. If you have a patched version of netcat which
2195 activates telnet remote echo and single char transfer, then you can
2196 use the following options to step up a netcat redirector to allow
2197 telnet on port 5555 to access the QEMU port.
2200 -serial udp::4555@@:4556
2201 @item netcat options:
2202 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
2203 @item telnet options:
2207 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay]
2208 The TCP Net Console has two modes of operation. It can send the serial
2209 I/O to a location or wait for a connection from a location. By default
2210 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
2211 the @var{server} option QEMU will wait for a client socket application
2212 to connect to the port before continuing, unless the @code{nowait}
2213 option was specified. The @code{nodelay} option disables the Nagle buffering
2214 algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only
2215 one TCP connection at a time is accepted. You can use @code{telnet} to
2216 connect to the corresponding character device.
2218 @item Example to send tcp console to 192.168.0.2 port 4444
2219 -serial tcp:192.168.0.2:4444
2220 @item Example to listen and wait on port 4444 for connection
2221 -serial tcp::4444,server
2222 @item Example to not wait and listen on ip 192.168.0.100 port 4444
2223 -serial tcp:192.168.0.100:4444,server,nowait
2226 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
2227 The telnet protocol is used instead of raw tcp sockets. The options
2228 work the same as if you had specified @code{-serial tcp}. The
2229 difference is that the port acts like a telnet server or client using
2230 telnet option negotiation. This will also allow you to send the
2231 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
2232 sequence. Typically in unix telnet you do it with Control-] and then
2233 type "send break" followed by pressing the enter key.
2235 @item unix:@var{path}[,server][,nowait]
2236 A unix domain socket is used instead of a tcp socket. The option works the
2237 same as if you had specified @code{-serial tcp} except the unix domain socket
2238 @var{path} is used for connections.
2240 @item mon:@var{dev_string}
2241 This is a special option to allow the monitor to be multiplexed onto
2242 another serial port. The monitor is accessed with key sequence of
2243 @key{Control-a} and then pressing @key{c}. See monitor access
2244 @ref{pcsys_keys} in the -nographic section for more keys.
2245 @var{dev_string} should be any one of the serial devices specified
2246 above. An example to multiplex the monitor onto a telnet server
2247 listening on port 4444 would be:
2249 @item -serial mon:telnet::4444,server,nowait
2253 Braille device. This will use BrlAPI to display the braille output on a real
2257 Three button serial mouse. Configure the guest to use Microsoft protocol.
2261 DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
2262 "-parallel dev redirect the parallel port to char device 'dev
'\n",
2265 @item -parallel @var{dev}
2267 Redirect the virtual parallel port to host device @var{dev} (same
2268 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
2269 be used to use hardware devices connected on the corresponding host
2272 This option can be used several times to simulate up to 3 parallel
2275 Use @code{-parallel none} to disable all parallel ports.
2278 DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
2279 "-monitor dev redirect the monitor to char device 'dev
'\n",
2282 @item -monitor @var{dev}
2284 Redirect the monitor to host device @var{dev} (same devices as the
2286 The default device is @code{vc} in graphical mode and @code{stdio} in
2289 DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
2290 "-qmp dev like -monitor but opens in 'control
' mode\n",
2293 @item -qmp @var{dev}
2295 Like -monitor but opens in 'control
' mode.
2298 DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
2299 "-mon chardev=[name][,mode=readline|control][,default]\n", QEMU_ARCH_ALL)
2301 @item -mon chardev=[name][,mode=readline|control][,default]
2303 Setup monitor on chardev @var{name}.
2306 DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
2307 "-debugcon dev redirect the debug console to char device 'dev
'\n",
2310 @item -debugcon @var{dev}
2312 Redirect the debug console to host device @var{dev} (same devices as the
2313 serial port). The debug console is an I/O port which is typically port
2314 0xe9; writing to that I/O port sends output to this device.
2315 The default device is @code{vc} in graphical mode and @code{stdio} in
2319 DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
2320 "-pidfile file write PID to 'file
'\n", QEMU_ARCH_ALL)
2322 @item -pidfile @var{file}
2324 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
2328 DEF("singlestep", 0, QEMU_OPTION_singlestep, \
2329 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL)
2333 Run the emulation in single step mode.
2336 DEF("S", 0, QEMU_OPTION_S, \
2337 "-S freeze CPU at startup (use 'c
' to start execution)\n",
2342 Do not start CPU at startup (you must type 'c
' in the monitor).
2345 DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
2346 "-gdb dev wait for gdb connection on 'dev
'\n", QEMU_ARCH_ALL)
2348 @item -gdb @var{dev}
2350 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
2351 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
2352 stdio are reasonable use case. The latter is allowing to start QEMU from
2353 within gdb and establish the connection via a pipe:
2355 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
2359 DEF("s", 0, QEMU_OPTION_s, \
2360 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
2365 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
2366 (@pxref{gdb_usage}).
2369 DEF("d", HAS_ARG, QEMU_OPTION_d, \
2370 "-d item1,... output log to /tmp/qemu.log (use -d ? for a list of log items)\n",
2375 Output log in /tmp/qemu.log
2378 DEF("D", HAS_ARG, QEMU_OPTION_D, \
2379 "-D logfile output log to logfile (instead of the default /tmp/qemu.log)\n",
2382 @item -D @var{logfile}
2384 Output log in @var{logfile} instead of /tmp/qemu.log
2387 DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
2388 "-hdachs c,h,s[,t]\n" \
2389 " force hard disk 0 physical geometry and the optional BIOS\n" \
2390 " translation (t=none or lba) (usually QEMU can guess them)\n",
2393 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
2395 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
2396 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
2397 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
2398 all those parameters. This option is useful for old MS-DOS disk
2402 DEF("L", HAS_ARG, QEMU_OPTION_L, \
2403 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
2408 Set the directory for the BIOS, VGA BIOS and keymaps.
2411 DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
2412 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL)
2414 @item -bios @var{file}
2416 Set the filename for the BIOS.
2419 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
2420 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL)
2424 Enable KVM full virtualization support. This option is only available
2425 if KVM support is enabled when compiling.
2428 DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
2429 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL)
2430 DEF("xen-create", 0, QEMU_OPTION_xen_create,
2431 "-xen-create create domain using xen hypercalls, bypassing xend\n"
2432 " warning: should not be used when xend is in use\n",
2434 DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
2435 "-xen-attach attach to existing xen domain\n"
2436 " xend will use this when starting QEMU\n",
2439 @item -xen-domid @var{id}
2441 Specify xen guest domain @var{id} (XEN only).
2444 Create domain using xen hypercalls, bypassing xend.
2445 Warning: should not be used when xend is in use (XEN only).
2448 Attach to existing xen domain.
2449 xend will use this when starting QEMU (XEN only).
2452 DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
2453 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL)
2457 Exit instead of rebooting.
2460 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
2461 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL)
2464 @findex -no-shutdown
2465 Don't exit QEMU on guest shutdown
, but instead only stop the emulation
.
2466 This allows
for instance switching to monitor to commit changes to the
2470 DEF("loadvm", HAS_ARG
, QEMU_OPTION_loadvm
, \
2471 "-loadvm [tag|id]\n" \
2472 " start right away with a saved state (loadvm in monitor)\n",
2475 @item
-loadvm @
var{file
}
2477 Start right away with a saved
state (@code
{loadvm
} in monitor
)
2481 DEF("daemonize", 0, QEMU_OPTION_daemonize
, \
2482 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL
)
2487 Daemonize the QEMU process after initialization
. QEMU will not detach from
2488 standard IO until it is ready to receive connections on any of its devices
.
2489 This option is a useful way
for external programs to launch QEMU without having
2490 to cope with initialization race conditions
.
2493 DEF("option-rom", HAS_ARG
, QEMU_OPTION_option_rom
, \
2494 "-option-rom rom load a file, rom, into the option ROM space\n",
2497 @item
-option
-rom @
var{file
}
2499 Load the contents of @
var{file
} as an option ROM
.
2500 This option is useful to load things like EtherBoot
.
2503 DEF("clock", HAS_ARG
, QEMU_OPTION_clock
, \
2504 "-clock force the use of the given methods for timer alarm.\n" \
2505 " To see what timers are available use -clock ?\n",
2508 @item
-clock @
var{method
}
2510 Force the use of the given methods
for timer alarm
. To see what timers
2511 are available use
-clock ?
.
2514 HXCOMM Options deprecated by
-rtc
2515 DEF("localtime", 0, QEMU_OPTION_localtime
, "", QEMU_ARCH_ALL
)
2516 DEF("startdate", HAS_ARG
, QEMU_OPTION_startdate
, "", QEMU_ARCH_ALL
)
2518 DEF("rtc", HAS_ARG
, QEMU_OPTION_rtc
, \
2519 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
2520 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
2525 @item
-rtc
[base
=utc|localtime|@
var{date
}][,clock
=host|vm
][,driftfix
=none|slew
]
2527 Specify @option
{base
} as @code
{utc
} or @code
{localtime
} to let the RTC start at the current
2528 UTC or local time
, respectively
. @code
{localtime
} is required
for correct date
in
2529 MS
-DOS or Windows
. To start at a specific point
in time
, provide @
var{date
} in the
2530 format @code
{2006-06-17T16
:01:21} or @code
{2006-06-17}. The
default base is UTC
.
2532 By
default the RTC is driven by the host system time
. This allows to use the
2533 RTC as accurate reference clock inside the guest
, specifically
if the host
2534 time is smoothly following an accurate external reference clock
, e
.g
. via NTP
.
2535 If you want to isolate the guest time from the host
, you can set @option
{clock
}
2536 to @code
{rt
} instead
. To even prevent it from progressing during suspension
,
2537 you can set it to @code
{vm
}.
2539 Enable @option
{driftfix
} (i386 targets only
) if you experience time drift problems
,
2540 specifically with Windows
' ACPI HAL. This option will try to figure out how
2541 many timer interrupts were not processed by the Windows guest and will
2545 DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
2546 "-icount [N|auto]\n" \
2547 " enable virtual instruction counter with 2^N clock ticks per\n" \
2548 " instruction\n", QEMU_ARCH_ALL)
2550 @item -icount [@var{N}|auto]
2552 Enable virtual instruction counter. The virtual cpu will execute one
2553 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
2554 then the virtual cpu speed will be automatically adjusted to keep virtual
2555 time within a few seconds of real time.
2557 Note that while this option can give deterministic behavior, it does not
2558 provide cycle accurate emulation. Modern CPUs contain superscalar out of
2559 order cores with complex cache hierarchies. The number of instructions
2560 executed often has little or no correlation with actual performance.
2563 DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
2564 "-watchdog i6300esb|ib700\n" \
2565 " enable virtual hardware watchdog [default=none]\n",
2568 @item -watchdog @var{model}
2570 Create a virtual hardware watchdog device. Once enabled (by a guest
2571 action), the watchdog must be periodically polled by an agent inside
2572 the guest or else the guest will be restarted.
2574 The @var{model} is the model of hardware watchdog to emulate. Choices
2575 for model are: @code{ib700} (iBASE 700) which is a very simple ISA
2576 watchdog with a single timer, or @code{i6300esb} (Intel 6300ESB I/O
2577 controller hub) which is a much more featureful PCI-based dual-timer
2578 watchdog. Choose a model for which your guest has drivers.
2580 Use @code{-watchdog ?} to list available hardware models. Only one
2581 watchdog can be enabled for a guest.
2584 DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
2585 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
2586 " action when watchdog fires [default=reset]\n",
2589 @item -watchdog-action @var{action}
2591 The @var{action} controls what QEMU will do when the watchdog timer
2594 @code{reset} (forcefully reset the guest).
2595 Other possible actions are:
2596 @code{shutdown} (attempt to gracefully shutdown the guest),
2597 @code{poweroff} (forcefully poweroff the guest),
2598 @code{pause} (pause the guest),
2599 @code{debug} (print a debug message and continue), or
2600 @code{none} (do nothing).
2602 Note that the @code{shutdown} action requires that the guest responds
2603 to ACPI signals, which it may not be able to do in the sort of
2604 situations where the watchdog would have expired, and thus
2605 @code{-watchdog-action shutdown} is not recommended for production use.
2610 @item -watchdog i6300esb -watchdog-action pause
2611 @item -watchdog ib700
2615 DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
2616 "-echr chr set terminal escape character instead of ctrl-a\n",
2620 @item -echr @var{numeric_ascii_value}
2622 Change the escape character used for switching to the monitor when using
2623 monitor and serial sharing. The default is @code{0x01} when using the
2624 @code{-nographic} option. @code{0x01} is equal to pressing
2625 @code{Control-a}. You can select a different character from the ascii
2626 control keys where 1 through 26 map to Control-a through Control-z. For
2627 instance you could use the either of the following to change the escape
2628 character to Control-t.
2635 DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
2636 "-virtioconsole c\n" \
2637 " set virtio console\n", QEMU_ARCH_ALL)
2639 @item -virtioconsole @var{c}
2640 @findex -virtioconsole
2643 This option is maintained for backward compatibility.
2645 Please use @code{-device virtconsole} for the new way of invocation.
2648 DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
2649 "-show-cursor show cursor\n", QEMU_ARCH_ALL)
2652 @findex -show-cursor
2656 DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
2657 "-tb-size n set TB size\n", QEMU_ARCH_ALL)
2659 @item -tb-size @var{n}
2664 DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
2665 "-incoming p prepare for incoming migration, listen on port p\n",
2668 @item -incoming @var{port}
2670 Prepare for incoming migration, listen on @var{port}.
2673 DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
2674 "-nodefaults don't create
default devices
\n", QEMU_ARCH_ALL)
2678 Don't create default devices. Normally, QEMU sets the default devices like serial
2679 port, parallel port, virtual console, monitor device, VGA adapter, floppy and
2680 CD-ROM drive and others. The @code{-nodefaults} option will disable all those
2685 DEF("chroot
", HAS_ARG, QEMU_OPTION_chroot, \
2686 "-chroot dir chroot to dir just before starting the VM
\n",
2690 @item -chroot @var{dir}
2692 Immediately before starting guest execution, chroot to the specified
2693 directory. Especially useful in combination with -runas.
2697 DEF("runas
", HAS_ARG, QEMU_OPTION_runas, \
2698 "-runas user change to user id user just before starting the VM
\n",
2702 @item -runas @var{user}
2704 Immediately before starting guest execution, drop root privileges, switching
2705 to the specified user.
2708 DEF("prom
-env
", HAS_ARG, QEMU_OPTION_prom_env,
2709 "-prom
-env variable
=value
\n"
2710 " set OpenBIOS nvram variables
\n",
2711 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
2713 @item -prom-env @var{variable}=@var{value}
2715 Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
2717 DEF("semihosting
", 0, QEMU_OPTION_semihosting,
2718 "-semihosting semihosting mode
\n", QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA)
2721 @findex -semihosting
2722 Semihosting mode (ARM, M68K, Xtensa only).
2724 DEF("old
-param
", 0, QEMU_OPTION_old_param,
2725 "-old
-param old param mode
\n", QEMU_ARCH_ARM)
2728 @findex -old-param (ARM)
2729 Old param mode (ARM only).
2732 DEF("sandbox
", HAS_ARG, QEMU_OPTION_sandbox, \
2733 "-sandbox
<arg
> Enable seccomp mode
2 system call
filter (default 'off').\n",
2738 Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
2739 disable it. The default is 'off'.
2742 DEF("readconfig
", HAS_ARG, QEMU_OPTION_readconfig,
2743 "-readconfig
<file
>\n", QEMU_ARCH_ALL)
2745 @item -readconfig @var{file}
2747 Read device configuration from @var{file}. This approach is useful when you want to spawn
2748 QEMU process with many command line options but you don't want to exceed the command line
2751 DEF("writeconfig
", HAS_ARG, QEMU_OPTION_writeconfig,
2752 "-writeconfig
<file
>\n"
2753 " read
/write config file
\n", QEMU_ARCH_ALL)
2755 @item -writeconfig @var{file}
2756 @findex -writeconfig
2757 Write device configuration to @var{file}. The @var{file} can be either filename to save
2758 command line and device configuration into file or dash @code{-}) character to print the
2759 output to stdout. This can be later used as input file for @code{-readconfig} option.
2761 DEF("nodefconfig
", 0, QEMU_OPTION_nodefconfig,
2763 " do not load
default config files at startup
\n",
2767 @findex -nodefconfig
2768 Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
2769 The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
2771 DEF("no
-user
-config
", 0, QEMU_OPTION_nouserconfig,
2773 " do not load user
-provided config files at startup
\n",
2776 @item -no-user-config
2777 @findex -no-user-config
2778 The @code{-no-user-config} option makes QEMU not load any of the user-provided
2779 config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config
2780 files from @var{datadir}.
2782 DEF("trace", HAS_ARG, QEMU_OPTION_trace,
2783 "-trace [events
=<file
>][,file
=<file
>]\n"
2784 " specify tracing options
\n",
2787 HXCOMM This line is not accurate, as some sub-options are backend-specific but
2788 HXCOMM HX does not support conditional compilation of text.
2789 @item -trace [events=@var{file}][,file=@var{file}]
2792 Specify tracing options.
2795 @item events=@var{file}
2796 Immediately enable events listed in @var{file}.
2797 The file must contain one event name (as listed in the @var{trace-events} file)
2799 This option is only available if QEMU has been compiled with
2800 either @var{simple} or @var{stderr} tracing backend.
2801 @item file=@var{file}
2802 Log output traces to @var{file}.
2804 This option is only available if QEMU has been compiled with
2805 the @var{simple} tracing backend.
2809 DEF("qtest
", HAS_ARG, QEMU_OPTION_qtest,
2810 "-qtest CHR specify tracing options
\n",
2813 DEF("qtest
-log
", HAS_ARG, QEMU_OPTION_qtest_log,
2814 "-qtest
-log LOG specify tracing options
\n",
2818 DEF("enable
-fips
", 0, QEMU_OPTION_enablefips,
2819 "-enable
-fips enable FIPS
140-2 compliance
\n",
2824 @findex -enable-fips
2825 Enable FIPS 140-2 compliance mode.
2828 HXCOMM This is the last statement. Insert new options before this line!