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
978 @item cga_hacks
=@
var{hack1
}[+@
var{hack2
},[...]]
979 Enable various extra CGA compatibility hacks
for programs that are
980 trying to directly set CGA modes without BIOS assistance nor
981 real knowledge of EGA
/VGA
. These might only work with
-vga std
.
984 @item palette_blanking
985 Wait to blank the screen until palette registers seem to actually be
986 modified
, instead of blanking it as soon as the palette address
bit (0x10)
987 of the attribute address
register (0x3c0) is cleared
.
989 Ignore attempts to change the VGA font
height (index
9),
990 cursor
start (index
10), and cursor
end (index
11) of the CRTC control
991 registers (0x3d5) if trying to set them to the
default for CGA fonts
992 instead of VGA fonts
.
994 Enable all CGA hacks
. More CGA hacks may be added
in future versions
1000 DEF("full-screen", 0, QEMU_OPTION_full_screen
,
1001 "-full-screen start in full screen\n", QEMU_ARCH_ALL
)
1004 @findex
-full
-screen
1005 Start
in full screen
.
1008 DEF("g", 1, QEMU_OPTION_g
,
1009 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
1010 QEMU_ARCH_PPC | QEMU_ARCH_SPARC
)
1012 @item
-g @
var{width
}x@
var{height
}[x@
var{depth
}]
1014 Set the initial graphical resolution and
depth (PPC
, SPARC only
).
1017 DEF("vnc", HAS_ARG
, QEMU_OPTION_vnc
,
1018 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL
)
1020 @item
-vnc @
var{display
}[,@
var{option
}[,@
var{option
}[,...]]]
1022 Normally
, QEMU uses SDL to display the VGA output
. With
this option
,
1023 you can have QEMU listen on VNC display @
var{display
} and redirect the VGA
1024 display over the VNC session
. It is very useful to enable the usb
1025 tablet device when
using this option (option @option
{-usbdevice
1026 tablet
}). When
using the VNC display
, you must use the @option
{-k
}
1027 parameter to set the keyboard layout
if you are not
using en
-us
. Valid
1028 syntax
for the @
var{display
} is
1032 @item @
var{host
}:@
var{d
}
1034 TCP connections will only be allowed from @
var{host
} on display @
var{d
}.
1035 By convention the TCP port is
5900+@
var{d
}. Optionally
, @
var{host
} can
1036 be omitted
in which
case the server will accept connections from any host
.
1038 @item unix
:@
var{path
}
1040 Connections will be allowed over UNIX domain sockets where @
var{path
} is the
1041 location of a unix socket to listen
for connections on
.
1045 VNC is initialized but not started
. The monitor @code
{change
} command
1046 can be used to later start the VNC server
.
1050 Following the @
var{display
} value there may be one or more @
var{option
} flags
1051 separated by commas
. Valid options are
1057 Connect to a listening VNC client via a ``reverse
'' connection
. The
1058 client is specified by the @
var{display
}. For reverse network
1059 connections (@
var{host
}:@
var{d
},@code
{reverse
}), the @
var{d
} argument
1060 is a TCP port number
, not a display number
.
1064 Require that password based authentication is used
for client connections
.
1066 The password must be set separately
using the @code
{set_password
} command
in
1067 the @ref
{pcsys_monitor
}. The syntax to change your password is
:
1068 @code
{set_password
<protocol
> <password
>} where
<protocol
> could be either
1071 If you would like to change
<protocol
> password expiration
, you should use
1072 @code
{expire_password
<protocol
> <expiration
-time
>} where expiration time could
1073 be one of the following options
: now
, never, +seconds or UNIX time of
1074 expiration
, e
.g
. +60 to make password expire
in 60 seconds
, or
1335196800
1075 to make password expire on
"Mon Apr 23 12:00:00 EDT 2012" (UNIX time
for this
1078 You can also use keywords
"now" or
"never" for the expiration time to
1079 allow
<protocol
> password to expire immediately or
never expire
.
1083 Require that client use TLS when communicating with the VNC server
. This
1084 uses anonymous TLS credentials so is susceptible to a man
-in-the
-middle
1085 attack
. It is recommended that
this option be combined with either the
1086 @option
{x509
} or @option
{x509verify
} options
.
1088 @item x509
=@
var{/path
/to
/certificate
/dir
}
1090 Valid
if @option
{tls
} is specified
. Require that x509 credentials are used
1091 for negotiating the TLS session
. The server will send its x509 certificate
1092 to the client
. It is recommended that a password be set on the VNC server
1093 to provide authentication of the client when
this is used
. The path following
1094 this option specifies where the x509 certificates are to be loaded from
.
1095 See the @ref
{vnc_security
} section
for details on generating certificates
.
1097 @item x509verify
=@
var{/path
/to
/certificate
/dir
}
1099 Valid
if @option
{tls
} is specified
. Require that x509 credentials are used
1100 for negotiating the TLS session
. The server will send its x509 certificate
1101 to the client
, and request that the client send its own x509 certificate
.
1102 The server will validate the client
's certificate against the CA certificate,
1103 and reject clients when validation fails. If the certificate authority is
1104 trusted, this is a sufficient authentication mechanism. You may still wish
1105 to set a password on the VNC server as a second authentication layer. The
1106 path following this option specifies where the x509 certificates are to
1107 be loaded from. See the @ref{vnc_security} section for details on generating
1112 Require that the client use SASL to authenticate with the VNC server.
1113 The exact choice of authentication method used is controlled from the
1114 system / user's SASL configuration file
for the
'qemu' service
. This
1115 is typically found
in /etc
/sasl2
/qemu
.conf
. If running QEMU as an
1116 unprivileged user
, an environment variable SASL_CONF_PATH can be used
1117 to make it search alternate locations
for the service config
.
1118 While some SASL auth methods can also provide data
encryption (eg GSSAPI
),
1119 it is recommended that SASL always be combined with the
'tls' and
1120 'x509' settings to enable use of SSL and server certificates
. This
1121 ensures a data encryption preventing compromise of authentication
1122 credentials
. See the @ref
{vnc_security
} section
for details on
using
1123 SASL authentication
.
1127 Turn on access control lists
for checking of the x509 client certificate
1128 and SASL party
. For x509 certs
, the ACL check is made against the
1129 certificate
's distinguished name. This is something that looks like
1130 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1131 made against the username, which depending on the SASL plugin, may
1132 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1133 When the @option{acl} flag is set, the initial access list will be
1134 empty, with a @code{deny} policy. Thus no one will be allowed to
1135 use the VNC server until the ACLs have been loaded. This can be
1136 achieved using the @code{acl} monitor command.
1140 Enable lossy compression methods (gradient, JPEG, ...). If this
1141 option is set, VNC client may receive lossy framebuffer updates
1142 depending on its encoding settings. Enabling this option can save
1143 a lot of bandwidth at the expense of quality.
1147 Disable adaptive encodings. Adaptive encodings are enabled by default.
1148 An adaptive encoding will try to detect frequently updated screen regions,
1149 and send updates in these regions using a lossy encoding (like JPEG).
1150 This can be really helpful to save bandwidth when playing videos. Disabling
1151 adaptive encodings allows to restore the original static behavior of encodings
1154 @item share=[allow-exclusive|force-shared|ignore]
1156 Set display sharing policy. 'allow
-exclusive
' allows clients to ask
1157 for exclusive access. As suggested by the rfb spec this is
1158 implemented by dropping other connections. Connecting multiple
1159 clients in parallel requires all clients asking for a shared session
1160 (vncviewer: -shared switch). This is the default. 'force
-shared
'
1161 disables exclusive client access. Useful for shared desktop sessions,
1162 where you don't want someone forgetting specify
-shared disconnect
1163 everybody
else. 'ignore' completely ignores the shared flag and
1164 allows everybody connect unconditionally
. Doesn
't conform to the rfb
1165 spec but is traditional QEMU behavior.
1174 ARCHHEADING(, QEMU_ARCH_I386)
1176 ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1181 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1182 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1187 Use it when installing Windows 2000 to avoid a disk full bug. After
1188 Windows 2000 is installed, you no longer need this option (this option
1189 slows down the IDE transfers).
1192 DEF("no-spurious-interrupt-hack", 0, QEMU_OPTION_no_spurious_interrupt_hack,
1193 "-no-spurious-interrupt-hack disable delivery of spurious interrupts\n",
1196 @item -no-spurious-interrupt-hack
1197 @findex -no-spurious-interrupt-hack
1198 Use it as a workaround for operating systems that drive PICs in a way that
1199 can generate spurious interrupts, but the OS doesn't handle spurious
1200 interrupts gracefully
. (e
.g
. late
80s
/early
90s versions of ATT UNIX
1204 HXCOMM Deprecated by
-rtc
1205 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack
, "", QEMU_ARCH_I386
)
1207 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk
,
1208 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1211 @item
-no
-fd
-bootchk
1212 @findex
-no
-fd
-bootchk
1213 Disable boot signature checking
for floppy disks
in Bochs BIOS
. It may
1214 be needed to boot from old floppy disks
.
1215 TODO
: check reference to Bochs BIOS
.
1218 DEF("no-acpi", 0, QEMU_OPTION_no_acpi
,
1219 "-no-acpi disable ACPI\n", QEMU_ARCH_I386
)
1223 Disable
ACPI (Advanced Configuration and Power Interface
) support
. Use
1224 it
if your guest OS complains about ACPI
problems (PC target machine
1228 DEF("no-hpet", 0, QEMU_OPTION_no_hpet
,
1229 "-no-hpet disable HPET\n", QEMU_ARCH_I386
)
1233 Disable HPET support
.
1236 DEF("acpitable", HAS_ARG
, QEMU_OPTION_acpitable
,
1237 "-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"
1238 " ACPI table description\n", QEMU_ARCH_I386
)
1240 @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
}]...]
1242 Add ACPI table with specified header fields and context from specified files
.
1243 For file
=, take whole ACPI table from the specified files
, including all
1244 ACPI
headers (possible overridden by other options
).
1245 For data
=, only data
1246 portion of the table is used
, all header information is specified
in the
1250 DEF("smbios", HAS_ARG
, QEMU_OPTION_smbios
,
1251 "-smbios file=binary\n"
1252 " load SMBIOS entry from binary file\n"
1253 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1254 " specify SMBIOS type 0 fields\n"
1255 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1256 " [,uuid=uuid][,sku=str][,family=str]\n"
1257 " specify SMBIOS type 1 fields\n", QEMU_ARCH_I386
)
1259 @item
-smbios file
=@
var{binary
}
1261 Load SMBIOS entry from binary file
.
1263 @item
-smbios type
=0[,vendor
=@
var{str
}][,version
=@
var{str
}][,date
=@
var{str
}][,release
=@
var{%d
.%d
}]
1265 Specify SMBIOS type
0 fields
1267 @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
}]
1268 Specify SMBIOS type
1 fields
1276 DEFHEADING(Network options
:)
1281 HXCOMM Legacy slirp
options (now moved to
-net user
):
1283 DEF("tftp", HAS_ARG
, QEMU_OPTION_tftp
, "", QEMU_ARCH_ALL
)
1284 DEF("bootp", HAS_ARG
, QEMU_OPTION_bootp
, "", QEMU_ARCH_ALL
)
1285 DEF("redir", HAS_ARG
, QEMU_OPTION_redir
, "", QEMU_ARCH_ALL
)
1287 DEF("smb", HAS_ARG
, QEMU_OPTION_smb
, "", QEMU_ARCH_ALL
)
1291 DEF("net", HAS_ARG
, QEMU_OPTION_net
,
1292 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
1293 " create a new Network Interface Card and connect it to VLAN 'n'\n"
1295 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=on|off]\n"
1296 " [,hostname=host][,dhcpstart=addr][,dns=addr][,tftp=dir][,bootfile=f]\n"
1297 " [,hostfwd=rule][,guestfwd=rule]"
1299 "[,smb=dir[,smbserver=addr]]\n"
1301 " connect the user mode network stack to VLAN 'n', configure its\n"
1302 " DHCP server and enabled optional services\n"
1305 "-net tap[,vlan=n][,name=str],ifname=name\n"
1306 " connect the host TAP network interface to VLAN 'n'\n"
1308 "-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"
1309 " connect the host TAP network interface to VLAN 'n' \n"
1310 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT
")\n"
1311 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT
")\n"
1312 " to deconfigure it\n"
1313 " use '[down]script=no' to disable script execution\n"
1314 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER
") to\n"
1316 " use 'fd=h' to connect to an already opened TAP interface\n"
1317 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
1318 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
1319 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1320 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1321 " use vhost=on to enable experimental in kernel accelerator\n"
1322 " (only has effect for virtio guests which use MSIX)\n"
1323 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1324 " use 'vhostfd=h' to connect to an already opened vhost net device\n"
1325 "-net bridge[,vlan=n][,name=str][,br=bridge][,helper=helper]\n"
1326 " connects a host TAP network interface to a host bridge device 'br'\n"
1327 " (default=" DEFAULT_BRIDGE_INTERFACE
") using the program 'helper'\n"
1328 " (default=" DEFAULT_BRIDGE_HELPER
")\n"
1330 "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n"
1331 " connect the vlan 'n' to another VLAN using a socket connection\n"
1332 "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1333 " connect the vlan 'n' to multicast maddr and port\n"
1334 " use 'localaddr=addr' to specify the host address to send packets from\n"
1335 "-net socket[,vlan=n][,name=str][,fd=h][,udp=host:port][,localaddr=host:port]\n"
1336 " connect the vlan 'n' to another VLAN using an UDP tunnel\n"
1338 "-net vde[,vlan=n][,name=str][,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1339 " connect the vlan 'n' to port 'n' of a vde switch running\n"
1340 " on host and listening for incoming connections on 'socketpath'.\n"
1341 " Use group 'groupname' and mode 'octalmode' to change default\n"
1342 " ownership and permissions for communication port.\n"
1344 "-net dump[,vlan=n][,file=f][,len=n]\n"
1345 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n"
1346 "-net none use it alone to have zero network devices. If no -net option\n"
1347 " is provided, the default is '-net nic -net user'\n", QEMU_ARCH_ALL
)
1348 DEF("netdev", HAS_ARG
, QEMU_OPTION_netdev
,
1358 "socket],id=str[,option][,option][,...]\n", QEMU_ARCH_ALL
)
1360 @item
-net nic
[,vlan
=@
var{n
}][,macaddr
=@
var{mac
}][,model
=@
var{type
}] [,name
=@
var{name
}][,addr
=@
var{addr
}][,vectors
=@
var{v
}]
1362 Create a
new Network Interface Card and connect it to VLAN @
var{n
} (@
var{n
}
1363 = 0 is the
default). The NIC is an e1000 by
default on the PC
1364 target
. Optionally
, the MAC address can be changed to @
var{mac
}, the
1365 device address set to @
var{addr
} (PCI cards only
),
1366 and a @
var{name
} can be assigned
for use
in monitor commands
.
1367 Optionally
, for PCI cards
, you can specify the number @
var{v
} of MSI
-X vectors
1368 that the card should have
; this option currently only affects virtio cards
; set
1369 @
var{v
} = 0 to disable MSI
-X
. If no @option
{-net
} option is specified
, a single
1370 NIC is created
. QEMU can emulate several different models of network card
.
1371 Valid values
for @
var{type
} are
1372 @code
{virtio
}, @code
{i82551
}, @code
{i82557b
}, @code
{i82559er
},
1373 @code
{ne2k_pci
}, @code
{ne2k_isa
}, @code
{pcnet
}, @code
{rtl8139
},
1374 @code
{e1000
}, @code
{smc91c111
}, @code
{lance
} and @code
{mcf_fec
}.
1375 Not all devices are supported on all targets
. Use
-net nic
,model
=?
1376 for a list of available devices
for your target
.
1378 @item
-net user
[,@
var{option
}][,@
var{option
}][,...]
1379 Use the user mode network stack which requires no administrator
1380 privilege to run
. Valid options are
:
1384 Connect user mode stack to VLAN @
var{n
} (@
var{n
} = 0 is the
default).
1386 @item name
=@
var{name
}
1387 Assign symbolic name
for use
in monitor commands
.
1389 @item net
=@
var{addr
}[/@
var{mask
}]
1390 Set IP network address the guest will see
. Optionally specify the netmask
,
1391 either
in the form a
.b
.c
.d or as number of valid top
-most bits
. Default is
1394 @item host
=@
var{addr
}
1395 Specify the guest
-visible address of the host
. Default is the
2nd IP
in the
1396 guest network
, i
.e
. x
.x
.x
.2.
1398 @item restrict
=on|off
1399 If
this option is enabled
, the guest will be isolated
, i
.e
. it will not be
1400 able to contact the host and no guest IP packets will be routed over the host
1401 to the outside
. This option does not affect any explicitly set forwarding rules
.
1403 @item hostname
=@
var{name
}
1404 Specifies the client hostname reported by the builtin DHCP server
.
1406 @item dhcpstart
=@
var{addr
}
1407 Specify the first of the
16 IPs the built
-in DHCP server can assign
. Default
1408 is the
15th to
31st IP
in the guest network
, i
.e
. x
.x
.x
.15 to x
.x
.x
.31.
1410 @item dns
=@
var{addr
}
1411 Specify the guest
-visible address of the virtual nameserver
. The address must
1412 be different from the host address
. Default is the
3rd IP
in the guest network
,
1415 @item tftp
=@
var{dir
}
1416 When
using the user mode network stack
, activate a built
-in TFTP
1417 server
. The files
in @
var{dir
} will be exposed as the root of a TFTP server
.
1418 The TFTP client on the guest must be configured
in binary
mode (use the command
1419 @code
{bin
} of the Unix TFTP client
).
1421 @item bootfile
=@
var{file
}
1422 When
using the user mode network stack
, broadcast @
var{file
} as the BOOTP
1423 filename
. In conjunction with @option
{tftp
}, this can be used to network boot
1424 a guest from a local directory
.
1426 Example (using pxelinux
):
1428 qemu
-system
-i386
-hda linux
.img
-boot n
-net user
,tftp
=/path
/to
/tftp
/files
,bootfile
=/pxelinux
.0
1431 @item smb
=@
var{dir
}[,smbserver
=@
var{addr
}]
1432 When
using the user mode network stack
, activate a built
-in SMB
1433 server so that Windows OSes can access to the host files
in @file
{@
var{dir
}}
1434 transparently
. The IP address of the SMB server can be set to @
var{addr
}. By
1435 default the
4th IP
in the guest network is used
, i
.e
. x
.x
.x
.4.
1437 In the guest Windows OS
, the line
:
1441 must be added
in the file @file
{C
:\WINDOWS\LMHOSTS
} (for windows
9x
/Me
)
1442 or @file
{C
:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS
} (Windows NT
/2000).
1444 Then @file
{@
var{dir
}} can be accessed
in @file
{\\smbserver\qemu
}.
1446 Note that a SAMBA server must be installed on the host OS
.
1447 QEMU was tested successfully with smbd versions from Red Hat
9,
1448 Fedora Core
3 and OpenSUSE
11.x
.
1450 @item hostfwd
=[tcp|udp
]:[@
var{hostaddr
}]:@
var{hostport
}-[@
var{guestaddr
}]:@
var{guestport
}
1451 Redirect incoming TCP or UDP connections to the host port @
var{hostport
} to
1452 the guest IP address @
var{guestaddr
} on guest port @
var{guestport
}. If
1453 @
var{guestaddr
} is not specified
, its value is x
.x
.x
.15 (default first address
1454 given by the built
-in DHCP server
). By specifying @
var{hostaddr
}, the rule can
1455 be bound to a specific host
interface. If no connection type is set
, TCP is
1456 used
. This option can be given multiple times
.
1458 For example
, to redirect host X11 connection from screen
1 to guest
1459 screen
0, use the following
:
1463 qemu
-system
-i386
-net user
,hostfwd
=tcp
:127.0.0.1:6001-:6000 [...]
1464 #
this host xterm should open
in the guest X11 server
1468 To redirect telnet connections from host port
5555 to telnet port on
1469 the guest
, use the following
:
1473 qemu
-system
-i386
-net user
,hostfwd
=tcp
::5555-:23 [...]
1474 telnet localhost
5555
1477 Then when you use on the host @code
{telnet localhost
5555}, you
1478 connect to the guest telnet server
.
1480 @item guestfwd
=[tcp
]:@
var{server
}:@
var{port
}-@
var{dev
}
1481 @item guestfwd
=[tcp
]:@
var{server
}:@
var{port
}-@
var{cmd
:command
}
1482 Forward guest TCP connections to the IP address @
var{server
} on port @
var{port
}
1483 to the character device @
var{dev
} or to a program executed by @
var{cmd
:command
}
1484 which gets spawned
for each connection
. This option can be given multiple times
.
1486 You can either use a chardev directly and have that one used throughout QEMU
's
1487 lifetime, like in the following example:
1490 # open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
1491 # the guest accesses it
1492 qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...]
1495 Or you can execute a command on every TCP connection established by the guest,
1496 so that QEMU behaves similar to an inetd process for that virtual server:
1499 # call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
1500 # and connect the TCP stream to its stdin/stdout
1501 qemu -net 'user
,guestfwd
=tcp
:10.0.2.100:1234-cmd
:netcat
10.10.1.1 4321'
1506 Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
1507 processed and applied to -net user. Mixing them with the new configuration
1508 syntax gives undefined results. Their use for new applications is discouraged
1509 as they will be removed from future versions.
1511 @item -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1512 Connect the host TAP network interface @var{name} to VLAN @var{n}.
1514 Use the network script @var{file} to configure it and the network script
1515 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
1516 automatically provides one. The default network configure script is
1517 @file{/etc/qemu-ifup} and the default network deconfigure script is
1518 @file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
1519 to disable script execution.
1521 If running QEMU as an unprivileged user, use the network helper
1522 @var{helper} to configure the TAP interface. The default network
1523 helper executable is @file{/usr/local/libexec/qemu-bridge-helper}.
1525 @option{fd}=@var{h} can be used to specify the handle of an already
1526 opened host TAP interface.
1531 #launch a QEMU instance with the default network script
1532 qemu-system-i386 linux.img -net nic -net tap
1536 #launch a QEMU instance with two NICs, each one connected
1538 qemu-system-i386 linux.img \
1539 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
1540 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
1544 #launch a QEMU instance with the default network helper to
1545 #connect a TAP device to bridge br0
1546 qemu-system-i386 linux.img \
1547 -net nic -net tap,"helper=/usr/local/libexec/qemu-bridge-helper"
1550 @item -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
1551 Connect a host TAP network interface to a host bridge device.
1553 Use the network helper @var{helper} to configure the TAP interface and
1554 attach it to the bridge. The default network helper executable is
1555 @file{/usr/local/libexec/qemu-bridge-helper} and the default bridge
1556 device is @file{br0}.
1561 #launch a QEMU instance with the default network helper to
1562 #connect a TAP device to bridge br0
1563 qemu-system-i386 linux.img -net bridge -net nic,model=virtio
1567 #launch a QEMU instance with the default network helper to
1568 #connect a TAP device to bridge qemubr0
1569 qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
1572 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1574 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
1575 machine using a TCP socket connection. If @option{listen} is
1576 specified, QEMU waits for incoming connections on @var{port}
1577 (@var{host} is optional). @option{connect} is used to connect to
1578 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
1579 specifies an already opened TCP socket.
1583 # launch a first QEMU instance
1584 qemu-system-i386 linux.img \
1585 -net nic,macaddr=52:54:00:12:34:56 \
1586 -net socket,listen=:1234
1587 # connect the VLAN 0 of this instance to the VLAN 0
1588 # of the first instance
1589 qemu-system-i386 linux.img \
1590 -net nic,macaddr=52:54:00:12:34:57 \
1591 -net socket,connect=127.0.0.1:1234
1594 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1596 Create a VLAN @var{n} shared with another QEMU virtual
1597 machines using a UDP multicast socket, effectively making a bus for
1598 every QEMU with same multicast address @var{maddr} and @var{port}.
1602 Several QEMU can be running on different hosts and share same bus (assuming
1603 correct multicast setup for these hosts).
1605 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
1606 @url{http://user-mode-linux.sf.net}.
1608 Use @option{fd=h} to specify an already opened UDP multicast socket.
1613 # launch one QEMU instance
1614 qemu-system-i386 linux.img \
1615 -net nic,macaddr=52:54:00:12:34:56 \
1616 -net socket,mcast=230.0.0.1:1234
1617 # launch another QEMU instance on same "bus"
1618 qemu-system-i386 linux.img \
1619 -net nic,macaddr=52:54:00:12:34:57 \
1620 -net socket,mcast=230.0.0.1:1234
1621 # launch yet another QEMU instance on same "bus"
1622 qemu-system-i386 linux.img \
1623 -net nic,macaddr=52:54:00:12:34:58 \
1624 -net socket,mcast=230.0.0.1:1234
1627 Example (User Mode Linux compat.):
1629 # launch QEMU instance (note mcast address selected
1631 qemu
-system
-i386 linux
.img \
1632 -net nic
,macaddr
=52:54:00:12:34:56 \
1633 -net socket
,mcast
=239.192.168.1:1102
1635 /path
/to
/linux ubd0
=/path
/to
/root_fs eth0
=mcast
1638 Example (send packets from host
's 1.2.3.4):
1640 qemu-system-i386 linux.img \
1641 -net nic,macaddr=52:54:00:12:34:56 \
1642 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
1645 @item -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1646 Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
1647 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
1648 and MODE @var{octalmode} to change default ownership and permissions for
1649 communication port. This option is only available if QEMU has been compiled
1650 with vde support enabled.
1655 vde_switch -F -sock /tmp/myswitch
1656 # launch QEMU instance
1657 qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch
1660 @item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
1661 Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
1662 At most @var{len} bytes (64k by default) per packet are stored. The file format is
1663 libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
1666 Indicate that no network devices should be configured. It is used to
1667 override the default configuration (@option{-net nic -net user}) which
1668 is activated if no @option{-net} options are provided.
1675 DEFHEADING(Character device options:)
1677 DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
1678 "-chardev null,id=id[,mux=on|off]\n"
1679 "-chardev socket,id=id[,host=host],port=host[,to=to][,ipv4][,ipv6][,nodelay]\n"
1680 " [,server][,nowait][,telnet][,mux=on|off] (tcp)\n"
1681 "-chardev socket,id=id,path=path[,server][,nowait][,telnet],[mux=on|off] (unix)\n"
1682 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
1683 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
1684 "-chardev msmouse,id=id[,mux=on|off]\n"
1685 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
1687 "-chardev file,id=id,path=path[,mux=on|off]\n"
1688 "-chardev pipe,id=id,path=path[,mux=on|off]\n"
1690 "-chardev console,id=id[,mux=on|off]\n"
1691 "-chardev serial,id=id,path=path[,mux=on|off]\n"
1693 "-chardev pty,id=id[,mux=on|off]\n"
1694 "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n"
1696 #ifdef CONFIG_BRLAPI
1697 "-chardev braille,id=id[,mux=on|off]\n"
1699 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
1700 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
1701 "-chardev tty,id=id,path=path[,mux=on|off]\n"
1703 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
1704 "-chardev parport,id=id,path=path[,mux=on|off]\n"
1706 #if defined(CONFIG_SPICE)
1707 "-chardev spicevmc,id=id,name=name[,debug=debug]\n"
1714 The general form of a character device option is:
1717 @item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
1735 The specific backend will determine the applicable options.
1737 All devices must have an id, which can be any string up to 127 characters long.
1738 It is used to uniquely identify this device in other command line directives.
1740 A character device may be used in multiplexing mode by multiple front-ends.
1741 The key sequence of @key{Control-a} and @key{c} will rotate the input focus
1742 between attached front-ends. Specify @option{mux=on} to enable this mode.
1744 Options to each backend are described below.
1746 @item -chardev null ,id=@var{id}
1747 A void device. This device will not emit any data, and will drop any data it
1748 receives. The null backend does not take any options.
1750 @item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet]
1752 Create a two-way stream socket, which can be either a TCP or a unix socket. A
1753 unix socket will be created if @option{path} is specified. Behaviour is
1754 undefined if TCP options are specified for a unix socket.
1756 @option{server} specifies that the socket shall be a listening socket.
1758 @option{nowait} specifies that QEMU should not block waiting for a client to
1759 connect to a listening socket.
1761 @option{telnet} specifies that traffic on the socket should interpret telnet
1764 TCP and unix socket options are given below:
1768 @item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
1770 @option{host} for a listening socket specifies the local address to be bound.
1771 For a connecting socket species the remote host to connect to. @option{host} is
1772 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
1774 @option{port} for a listening socket specifies the local port to be bound. For a
1775 connecting socket specifies the port on the remote host to connect to.
1776 @option{port} can be given as either a port number or a service name.
1777 @option{port} is required.
1779 @option{to} is only relevant to listening sockets. If it is specified, and
1780 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
1781 to and including @option{to} until it succeeds. @option{to} must be specified
1784 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1785 If neither is specified the socket may use either protocol.
1787 @option{nodelay} disables the Nagle algorithm.
1789 @item unix options: path=@var{path}
1791 @option{path} specifies the local path of the unix socket. @option{path} is
1796 @item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
1798 Sends all traffic from the guest to a remote host over UDP.
1800 @option{host} specifies the remote host to connect to. If not specified it
1801 defaults to @code{localhost}.
1803 @option{port} specifies the port on the remote host to connect to. @option{port}
1806 @option{localaddr} specifies the local address to bind to. If not specified it
1807 defaults to @code{0.0.0.0}.
1809 @option{localport} specifies the local port to bind to. If not specified any
1810 available local port will be used.
1812 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1813 If neither is specified the device may use either protocol.
1815 @item -chardev msmouse ,id=@var{id}
1817 Forward QEMU's emulated msmouse events to the guest
. @option
{msmouse
} does not
1820 @item
-chardev vc
,id
=@
var{id
} [[,width
=@
var{width
}] [,height
=@
var{height
}]] [[,cols
=@
var{cols
}] [,rows
=@
var{rows
}]]
1822 Connect to a QEMU text console
. @option
{vc
} may optionally be given a specific
1825 @option
{width
} and @option
{height
} specify the width and height respectively of
1826 the console
, in pixels
.
1828 @option
{cols
} and @option
{rows
} specify that the console be sized to fit a text
1829 console with the given dimensions
.
1831 @item
-chardev file
,id
=@
var{id
} ,path
=@
var{path
}
1833 Log all traffic received from the guest to a file
.
1835 @option
{path
} specifies the path of the file to be opened
. This file will be
1836 created
if it does not already exist
, and overwritten
if it does
. @option
{path
}
1839 @item
-chardev pipe
,id
=@
var{id
} ,path
=@
var{path
}
1841 Create a two
-way connection to the guest
. The behaviour differs slightly between
1842 Windows hosts and other hosts
:
1844 On Windows
, a single duplex pipe will be created at
1845 @file
{\\.pipe\@option
{path
}}.
1847 On other hosts
, 2 pipes will be created called @file
{@option
{path
}.in} and
1848 @file
{@option
{path
}.out
}. Data written to @file
{@option
{path
}.in} will be
1849 received by the guest
. Data written by the guest can be read from
1850 @file
{@option
{path
}.out
}. QEMU will not create these fifos
, and requires them to
1853 @option
{path
} forms part of the pipe path as described above
. @option
{path
} is
1856 @item
-chardev console
,id
=@
var{id
}
1858 Send traffic from the guest to QEMU
's standard output. @option{console} does not
1861 @option{console} is only available on Windows hosts.
1863 @item -chardev serial ,id=@var{id} ,path=@option{path}
1865 Send traffic from the guest to a serial device on the host.
1868 only available on Windows hosts.
1870 @option{path} specifies the name of the serial device to open.
1872 @item -chardev pty ,id=@var{id}
1874 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
1875 not take any options.
1877 @option{pty} is not available on Windows hosts.
1879 @item -chardev stdio ,id=@var{id} [,signal=on|off]
1880 Connect to standard input and standard output of the QEMU process.
1882 @option{signal} controls if signals are enabled on the terminal, that includes
1883 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
1884 default, use @option{signal=off} to disable it.
1886 @option{stdio} is not available on Windows hosts.
1888 @item -chardev braille ,id=@var{id}
1890 Connect to a local BrlAPI server. @option{braille} does not take any options.
1892 @item -chardev tty ,id=@var{id} ,path=@var{path}
1894 Connect to a local tty device.
1896 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
1899 @option{path} specifies the path to the tty. @option{path} is required.
1901 @item -chardev parport ,id=@var{id} ,path=@var{path}
1903 @option{parport} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
1905 Connect to a local parallel port.
1907 @option{path} specifies the path to the parallel port device. @option{path} is
1910 @item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
1912 @option{spicevmc} is only available when spice support is built in.
1914 @option{debug} debug level for spicevmc
1916 @option{name} name of spice channel to connect to
1918 Connect to a spice virtual machine channel, such as vdiport.
1926 DEFHEADING(Device URL Syntax:)
1928 In addition to using normal file images for the emulated storage devices,
1929 QEMU can also use networked resources such as iSCSI devices. These are
1930 specified using a special URL syntax.
1934 iSCSI support allows QEMU to access iSCSI resources directly and use as
1935 images for the guest storage. Both disk and cdrom images are supported.
1937 Syntax for specifying iSCSI LUNs is
1938 ``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
1940 By default qemu will use the iSCSI initiator-name
1941 'iqn
.2008-11.org
.linux
-kvm
[:<name
>]' but this can also be set from the command
1942 line or a configuration file.
1945 Example (without authentication):
1947 qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
1948 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
1949 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
1952 Example (CHAP username/password via URL):
1954 qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
1957 Example (CHAP username/password via environment variables):
1959 LIBISCSI_CHAP_USERNAME="user" \
1960 LIBISCSI_CHAP_PASSWORD="password" \
1961 qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
1964 iSCSI support is an optional feature of QEMU and only available when
1965 compiled and linked against libiscsi.
1967 DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
1968 "-iscsi [user=user][,password=password]\n"
1969 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
1970 " [,initiator-name=iqn]\n"
1971 " iSCSI session parameters\n", QEMU_ARCH_ALL)
1974 iSCSI parameters such as username and password can also be specified via
1975 a configuration file. See qemu-doc for more information and examples.
1978 QEMU supports NBD (Network Block Devices) both using TCP protocol as well
1979 as Unix Domain Sockets.
1981 Syntax for specifying a NBD device using TCP
1982 ``nbd:<server-ip>:<port>[:exportname=<export>]''
1984 Syntax for specifying a NBD device using Unix Domain Sockets
1985 ``nbd:unix:<domain-socket>[:exportname=<export>]''
1990 qemu-system-i386 --drive file=nbd:192.0.2.1:30000
1993 Example for Unix Domain Sockets
1995 qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket
1999 Sheepdog is a distributed storage system for QEMU.
2000 QEMU supports using either local sheepdog devices or remote networked
2003 Syntax for specifying a sheepdog device
2005 ``sheepdog:<vdiname>''
2007 ``sheepdog:<vdiname>:<snapid>''
2009 ``sheepdog:<vdiname>:<tag>''
2011 ``sheepdog:<host>:<port>:<vdiname>''
2013 ``sheepdog:<host>:<port>:<vdiname>:<snapid>''
2015 ``sheepdog:<host>:<port>:<vdiname>:<tag>''
2020 qemu-system-i386 --drive file=sheepdog:192.0.2.1:30000:MyVirtualMachine
2023 See also @url{http://http://www.osrg.net/sheepdog/}.
2028 DEFHEADING(Bluetooth(R) options:)
2030 DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
2031 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands
\n" \
2032 "-bt hci
,host
[:id
]\n" \
2033 " use host
's HCI with the given name\n" \
2034 "-bt hci[,vlan=n]\n" \
2035 " emulate a standard HCI in virtual scatternet 'n
'\n" \
2036 "-bt vhci[,vlan=n]\n" \
2037 " add host computer to virtual scatternet 'n
' using VHCI\n" \
2038 "-bt device:dev[,vlan=n]\n" \
2039 " emulate a bluetooth device 'dev
' in scatternet 'n
'\n",
2046 Defines the function of the corresponding Bluetooth HCI. -bt options
2047 are matched with the HCIs present in the chosen machine type. For
2048 example when emulating a machine with only one HCI built into it, only
2049 the first @code{-bt hci[...]} option is valid and defines the HCI's
2050 logic
. The Transport Layer is decided by the machine type
. Currently
2051 the machines @code
{n800
} and @code
{n810
} have one HCI and all other
2055 The following three types are recognized
:
2059 (default) The corresponding Bluetooth HCI assumes no internal logic
2060 and will not respond to any HCI commands or emit events
.
2062 @item
-bt hci
,host
[:@
var{id
}]
2063 (@code
{bluez
} only
) The corresponding HCI passes commands
/ events
2064 to
/ from the physical HCI identified by the name @
var{id
} (default:
2065 @code
{hci0
}) on the computer running QEMU
. Only available on @code
{bluez
}
2066 capable systems like Linux
.
2068 @item
-bt hci
[,vlan
=@
var{n
}]
2069 Add a virtual
, standard HCI that will participate
in the Bluetooth
2070 scatternet @
var{n
} (default @code
{0}). Similarly to @option
{-net
}
2071 VLANs
, devices inside a bluetooth network @
var{n
} can only communicate
2072 with other devices
in the same
network (scatternet
).
2075 @item
-bt vhci
[,vlan
=@
var{n
}]
2076 (Linux
-host only
) Create a HCI
in scatternet @
var{n
} (default 0) attached
2077 to the host bluetooth stack instead of to the emulated target
. This
2078 allows the host and target machines to participate
in a common scatternet
2079 and communicate
. Requires the Linux @code
{vhci
} driver installed
. Can
2080 be used as following
:
2083 qemu
-system
-i386
[...OPTIONS
...] -bt hci
,vlan
=5 -bt vhci
,vlan
=5
2086 @item
-bt device
:@
var{dev
}[,vlan
=@
var{n
}]
2087 Emulate a bluetooth device @
var{dev
} and place it
in network @
var{n
}
2088 (default @code
{0}). QEMU can only emulate one type of bluetooth devices
2093 Virtual wireless keyboard implementing the HIDP bluetooth profile
.
2100 DEFHEADING(Linux
/Multiboot boot specific
:)
2103 When
using these options
, you can use a given Linux or Multiboot
2104 kernel without installing it
in the disk image
. It can be useful
2105 for easier testing of various kernels
.
2110 DEF("kernel", HAS_ARG
, QEMU_OPTION_kernel
, \
2111 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL
)
2113 @item
-kernel @
var{bzImage
}
2115 Use @
var{bzImage
} as kernel image
. The kernel can be either a Linux kernel
2116 or
in multiboot format
.
2119 DEF("append", HAS_ARG
, QEMU_OPTION_append
, \
2120 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL
)
2122 @item
-append @
var{cmdline
}
2124 Use @
var{cmdline
} as kernel command line
2127 DEF("initrd", HAS_ARG
, QEMU_OPTION_initrd
, \
2128 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL
)
2130 @item
-initrd @
var{file
}
2132 Use @
var{file
} as initial ram disk
.
2134 @item
-initrd
"@var{file1} arg=foo,@var{file2}"
2136 This syntax is only available with multiboot
.
2138 Use @
var{file1
} and @
var{file2
} as modules and pass arg
=foo as parameter to the
2142 DEF("dtb", HAS_ARG
, QEMU_OPTION_dtb
, \
2143 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL
)
2145 @item
-dtb @
var{file
}
2147 Use @
var{file
} as a device tree
binary (dtb
) image and pass it to the kernel
2157 DEFHEADING(Debug
/Expert options
:)
2163 DEF("serial", HAS_ARG
, QEMU_OPTION_serial
, \
2164 "-serial dev redirect the serial port to char device 'dev'\n",
2167 @item
-serial @
var{dev
}
2169 Redirect the virtual serial port to host character device
2170 @
var{dev
}. The
default device is @code
{vc
} in graphical mode and
2171 @code
{stdio
} in non graphical mode
.
2173 This option can be used several times to simulate up to
4 serial
2176 Use @code
{-serial none
} to disable all serial ports
.
2178 Available character devices are
:
2180 @item vc
[:@
var{W
}x@
var{H
}]
2181 Virtual console
. Optionally
, a width and height can be given
in pixel with
2185 It is also possible to specify width or height
in characters
:
2190 [Linux only
] Pseudo
TTY (a
new PTY is automatically allocated
)
2192 No device is allocated
.
2196 [Linux only
] Use host tty
, e
.g
. @file
{/dev
/ttyS0
}. The host serial port
2197 parameters are set according to the emulated ones
.
2198 @item
/dev
/parport@
var{N
}
2199 [Linux only
, parallel port only
] Use host parallel port
2200 @
var{N
}. Currently SPP and EPP parallel port features can be used
.
2201 @item file
:@
var{filename
}
2202 Write output to @
var{filename
}. No character can be read
.
2204 [Unix only
] standard input
/output
2205 @item pipe
:@
var{filename
}
2206 name pipe @
var{filename
}
2208 [Windows only
] Use host serial port @
var{n
}
2209 @item udp
:[@
var{remote_host
}]:@
var{remote_port
}[@@
[@
var{src_ip
}]:@
var{src_port
}]
2210 This
implements UDP Net Console
.
2211 When @
var{remote_host
} or @
var{src_ip
} are not specified
2212 they
default to @code
{0.0.0.0}.
2213 When not
using a specified @
var{src_port
} a random port is automatically chosen
.
2215 If you just want a simple readonly console you can use @code
{netcat
} or
2216 @code
{nc
}, by starting QEMU with
: @code
{-serial udp
::4555} and nc as
:
2217 @code
{nc
-u
-l
-p
4555}. Any time QEMU writes something to that port it
2218 will appear
in the netconsole session
.
2220 If you plan to send characters back via netconsole or you want to stop
2221 and start QEMU a lot of times
, you should have QEMU use the same
2222 source port each time by
using something like @code
{-serial
2223 udp
::4555@@
:4556} to QEMU
. Another approach is to use a patched
2224 version of netcat which can listen to a TCP port and send and receive
2225 characters via udp
. If you have a patched version of netcat which
2226 activates telnet remote echo and single char transfer
, then you can
2227 use the following options to step up a netcat redirector to allow
2228 telnet on port
5555 to access the QEMU port
.
2231 -serial udp
::4555@@
:4556
2232 @item netcat options
:
2233 -u
-P
4555 -L
0.0.0.0:4556 -t
-p
5555 -I
-T
2234 @item telnet options
:
2238 @item tcp
:[@
var{host
}]:@
var{port
}[,@
var{server
}][,nowait
][,nodelay
]
2239 The TCP Net Console has two modes of operation
. It can send the serial
2240 I
/O to a location or wait
for a connection from a location
. By
default
2241 the TCP Net Console is sent to @
var{host
} at the @
var{port
}. If you use
2242 the @
var{server
} option QEMU will wait
for a client socket application
2243 to connect to the port before continuing
, unless the @code
{nowait
}
2244 option was specified
. The @code
{nodelay
} option disables the Nagle buffering
2245 algorithm
. If @
var{host
} is omitted
, 0.0.0.0 is assumed
. Only
2246 one TCP connection at a time is accepted
. You can use @code
{telnet
} to
2247 connect to the corresponding character device
.
2249 @item Example to send tcp console to
192.168.0.2 port
4444
2250 -serial tcp
:192.168.0.2:4444
2251 @item Example to listen and wait on port
4444 for connection
2252 -serial tcp
::4444,server
2253 @item Example to not wait and listen on ip
192.168.0.100 port
4444
2254 -serial tcp
:192.168.0.100:4444,server
,nowait
2257 @item telnet
:@
var{host
}:@
var{port
}[,server
][,nowait
][,nodelay
]
2258 The telnet protocol is used instead of raw tcp sockets
. The options
2259 work the same as
if you had specified @code
{-serial tcp
}. The
2260 difference is that the port acts like a telnet server or client
using
2261 telnet option negotiation
. This will also allow you to send the
2262 MAGIC_SYSRQ sequence
if you use a telnet that supports sending the
break
2263 sequence
. Typically
in unix telnet you
do it with Control
-] and then
2264 type
"send break" followed by pressing the enter key
.
2266 @item unix
:@
var{path
}[,server
][,nowait
]
2267 A unix domain socket is used instead of a tcp socket
. The option works the
2268 same as
if you had specified @code
{-serial tcp
} except the unix domain socket
2269 @
var{path
} is used
for connections
.
2271 @item mon
:@
var{dev_string
}
2272 This is a special option to allow the monitor to be multiplexed onto
2273 another serial port
. The monitor is accessed with key sequence of
2274 @key
{Control
-a
} and then pressing @key
{c
}. See monitor access
2275 @ref
{pcsys_keys
} in the
-nographic section
for more keys
.
2276 @
var{dev_string
} should be any one of the serial devices specified
2277 above
. An example to multiplex the monitor onto a telnet server
2278 listening on port
4444 would be
:
2280 @item
-serial mon
:telnet
::4444,server
,nowait
2284 Braille device
. This will use BrlAPI to display the braille output on a real
2288 Three button serial mouse
. Configure the guest to use Microsoft protocol
.
2292 DEF("parallel", HAS_ARG
, QEMU_OPTION_parallel
, \
2293 "-parallel dev redirect the parallel port to char device 'dev'\n",
2296 @item
-parallel @
var{dev
}
2298 Redirect the virtual parallel port to host device @
var{dev
} (same
2299 devices as the serial port
). On Linux hosts
, @file
{/dev
/parportN
} can
2300 be used to use hardware devices connected on the corresponding host
2303 This option can be used several times to simulate up to
3 parallel
2306 Use @code
{-parallel none
} to disable all parallel ports
.
2309 DEF("monitor", HAS_ARG
, QEMU_OPTION_monitor
, \
2310 "-monitor dev redirect the monitor to char device 'dev'\n",
2313 @item
-monitor @
var{dev
}
2315 Redirect the monitor to host device @
var{dev
} (same devices as the
2317 The
default device is @code
{vc
} in graphical mode and @code
{stdio
} in
2320 DEF("qmp", HAS_ARG
, QEMU_OPTION_qmp
, \
2321 "-qmp dev like -monitor but opens in 'control' mode\n",
2324 @item
-qmp @
var{dev
}
2326 Like
-monitor but opens
in 'control' mode
.
2329 DEF("mon", HAS_ARG
, QEMU_OPTION_mon
, \
2330 "-mon chardev=[name][,mode=readline|control][,default]\n", QEMU_ARCH_ALL
)
2332 @item
-mon chardev
=[name
][,mode
=readline|control
][,default]
2334 Setup monitor on chardev @
var{name
}.
2337 DEF("debugcon", HAS_ARG
, QEMU_OPTION_debugcon
, \
2338 "-debugcon dev redirect the debug console to char device 'dev'\n",
2341 @item
-debugcon @
var{dev
}
2343 Redirect the debug console to host device @
var{dev
} (same devices as the
2344 serial port
). The debug console is an I
/O port which is typically port
2345 0xe9; writing to that I
/O port sends output to
this device
.
2346 The
default device is @code
{vc
} in graphical mode and @code
{stdio
} in
2350 DEF("pidfile", HAS_ARG
, QEMU_OPTION_pidfile
, \
2351 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL
)
2353 @item
-pidfile @
var{file
}
2355 Store the QEMU process PID
in @
var{file
}. It is useful
if you launch QEMU
2359 DEF("singlestep", 0, QEMU_OPTION_singlestep
, \
2360 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL
)
2364 Run the emulation
in single step mode
.
2367 DEF("S", 0, QEMU_OPTION_S
, \
2368 "-S freeze CPU at startup (use 'c' to start execution)\n",
2373 Do not start CPU at
startup (you must type
'c' in the monitor
).
2376 DEF("gdb", HAS_ARG
, QEMU_OPTION_gdb
, \
2377 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL
)
2379 @item
-gdb @
var{dev
}
2381 Wait
for gdb connection on device @
var{dev
} (@pxref
{gdb_usage
}). Typical
2382 connections will likely be TCP
-based
, but also UDP
, pseudo TTY
, or even
2383 stdio are reasonable use
case. The latter is allowing to start QEMU from
2384 within gdb and establish the connection via a pipe
:
2386 (gdb
) target remote | exec qemu
-system
-i386
-gdb stdio
...
2390 DEF("s", 0, QEMU_OPTION_s
, \
2391 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT
"\n",
2396 Shorthand
for -gdb tcp
::1234, i
.e
. open a gdbserver on TCP port
1234
2397 (@pxref
{gdb_usage
}).
2400 DEF("d", HAS_ARG
, QEMU_OPTION_d
, \
2401 "-d item1,... output log to /tmp/qemu.log (use -d ? for a list of log items)\n",
2406 Output log
in /tmp
/qemu
.log
2409 DEF("D", HAS_ARG
, QEMU_OPTION_D
, \
2410 "-D logfile output log to logfile (instead of the default /tmp/qemu.log)\n",
2413 @item
-D @
var{logfile
}
2415 Output log
in @
var{logfile
} instead of
/tmp
/qemu
.log
2418 DEF("hdachs", HAS_ARG
, QEMU_OPTION_hdachs
, \
2419 "-hdachs c,h,s[,t]\n" \
2420 " force hard disk 0 physical geometry and the optional BIOS\n" \
2421 " translation (t=none or lba) (usually QEMU can guess them)\n",
2424 @item
-hdachs @
var{c
},@
var{h
},@
var{s
},[,@
var{t
}]
2426 Force hard disk
0 physical
geometry (1 <= @
var{c
} <= 16383, 1 <=
2427 @
var{h
} <= 16, 1 <= @
var{s
} <= 63) and optionally force the BIOS
2428 translation
mode (@
var{t
}=none
, lba or auto
). Usually QEMU can guess
2429 all those parameters
. This option is useful
for old MS
-DOS disk
2433 DEF("L", HAS_ARG
, QEMU_OPTION_L
, \
2434 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
2439 Set the directory
for the BIOS
, VGA BIOS and keymaps
.
2442 DEF("bios", HAS_ARG
, QEMU_OPTION_bios
, \
2443 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL
)
2445 @item
-bios @
var{file
}
2447 Set the filename
for the BIOS
.
2450 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm
, \
2451 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL
)
2455 Enable KVM full virtualization support
. This option is only available
2456 if KVM support is enabled when compiling
.
2459 DEF("xen-domid", HAS_ARG
, QEMU_OPTION_xen_domid
,
2460 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL
)
2461 DEF("xen-create", 0, QEMU_OPTION_xen_create
,
2462 "-xen-create create domain using xen hypercalls, bypassing xend\n"
2463 " warning: should not be used when xend is in use\n",
2465 DEF("xen-attach", 0, QEMU_OPTION_xen_attach
,
2466 "-xen-attach attach to existing xen domain\n"
2467 " xend will use this when starting QEMU\n",
2470 @item
-xen
-domid @
var{id
}
2472 Specify xen guest domain @
var{id
} (XEN only
).
2475 Create domain
using xen hypercalls
, bypassing xend
.
2476 Warning
: should not be used when xend is
in use (XEN only
).
2479 Attach to existing xen domain
.
2480 xend will use
this when starting
QEMU (XEN only
).
2483 DEF("no-reboot", 0, QEMU_OPTION_no_reboot
, \
2484 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL
)
2488 Exit instead of rebooting
.
2491 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown
, \
2492 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL
)
2495 @findex
-no
-shutdown
2496 Don
't exit QEMU on guest shutdown, but instead only stop the emulation.
2497 This allows for instance switching to monitor to commit changes to the
2501 DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
2502 "-loadvm [tag|id]\n" \
2503 " start right away with a saved state (loadvm in monitor)\n",
2506 @item -loadvm @var{file}
2508 Start right away with a saved state (@code{loadvm} in monitor)
2512 DEF("daemonize", 0, QEMU_OPTION_daemonize, \
2513 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
2518 Daemonize the QEMU process after initialization. QEMU will not detach from
2519 standard IO until it is ready to receive connections on any of its devices.
2520 This option is a useful way for external programs to launch QEMU without having
2521 to cope with initialization race conditions.
2524 DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
2525 "-option-rom rom load a file, rom, into the option ROM space\n",
2528 @item -option-rom @var{file}
2530 Load the contents of @var{file} as an option ROM.
2531 This option is useful to load things like EtherBoot.
2534 DEF("clock", HAS_ARG, QEMU_OPTION_clock, \
2535 "-clock force the use of the given methods for timer alarm.\n" \
2536 " To see what timers are available use -clock ?\n",
2539 @item -clock @var{method}
2541 Force the use of the given methods for timer alarm. To see what timers
2542 are available use -clock ?.
2545 HXCOMM Options deprecated by -rtc
2546 DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
2547 DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
2549 DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
2550 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
2551 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
2556 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
2558 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
2559 UTC or local time, respectively. @code{localtime} is required for correct date in
2560 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
2561 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
2563 By default the RTC is driven by the host system time. This allows to use the
2564 RTC as accurate reference clock inside the guest, specifically if the host
2565 time is smoothly following an accurate external reference clock, e.g. via NTP.
2566 If you want to isolate the guest time from the host, you can set @option{clock}
2567 to @code{rt} instead. To even prevent it from progressing during suspension,
2568 you can set it to @code{vm}.
2570 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
2571 specifically with Windows' ACPI HAL
. This option will
try to figure out how
2572 many timer interrupts were not processed by the Windows guest and will
2576 DEF("icount", HAS_ARG
, QEMU_OPTION_icount
, \
2577 "-icount [N|auto]\n" \
2578 " enable virtual instruction counter with 2^N clock ticks per\n" \
2579 " instruction\n", QEMU_ARCH_ALL
)
2581 @item
-icount
[@
var{N
}|auto
]
2583 Enable virtual instruction counter
. The virtual cpu will execute one
2584 instruction every
2^@
var{N
} ns of virtual time
. If @code
{auto
} is specified
2585 then the virtual cpu speed will be automatically adjusted to keep virtual
2586 time within a few seconds of real time
.
2588 Note that
while this option can give deterministic behavior
, it does not
2589 provide cycle accurate emulation
. Modern CPUs contain superscalar out of
2590 order cores with complex cache hierarchies
. The number of instructions
2591 executed often has little or no correlation with actual performance
.
2594 DEF("watchdog", HAS_ARG
, QEMU_OPTION_watchdog
, \
2595 "-watchdog i6300esb|ib700\n" \
2596 " enable virtual hardware watchdog [default=none]\n",
2599 @item
-watchdog @
var{model
}
2601 Create a virtual hardware watchdog device
. Once
enabled (by a guest
2602 action
), the watchdog must be periodically polled by an agent inside
2603 the guest or
else the guest will be restarted
.
2605 The @
var{model
} is the model of hardware watchdog to emulate
. Choices
2606 for model are
: @code
{ib700
} (iBASE
700) which is a very simple ISA
2607 watchdog with a single timer
, or @code
{i6300esb
} (Intel
6300ESB I
/O
2608 controller hub
) which is a much more featureful PCI
-based dual
-timer
2609 watchdog
. Choose a model
for which your guest has drivers
.
2611 Use @code
{-watchdog ?
} to list available hardware models
. Only one
2612 watchdog can be enabled
for a guest
.
2615 DEF("watchdog-action", HAS_ARG
, QEMU_OPTION_watchdog_action
, \
2616 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
2617 " action when watchdog fires [default=reset]\n",
2620 @item
-watchdog
-action @
var{action
}
2622 The @
var{action
} controls what QEMU will
do when the watchdog timer
2625 @code
{reset
} (forcefully reset the guest
).
2626 Other possible actions are
:
2627 @code
{shutdown
} (attempt to gracefully shutdown the guest
),
2628 @code
{poweroff
} (forcefully poweroff the guest
),
2629 @code
{pause
} (pause the guest
),
2630 @code
{debug
} (print a debug message and
continue), or
2631 @code
{none
} (do nothing
).
2633 Note that the @code
{shutdown
} action requires that the guest responds
2634 to ACPI signals
, which it may not be able to
do in the sort of
2635 situations where the watchdog would have expired
, and thus
2636 @code
{-watchdog
-action shutdown
} is not recommended
for production use
.
2641 @item
-watchdog i6300esb
-watchdog
-action pause
2642 @item
-watchdog ib700
2646 DEF("echr", HAS_ARG
, QEMU_OPTION_echr
, \
2647 "-echr chr set terminal escape character instead of ctrl-a\n",
2651 @item
-echr @
var{numeric_ascii_value
}
2653 Change the escape character used
for switching to the monitor when
using
2654 monitor and serial sharing
. The
default is @code
{0x01} when
using the
2655 @code
{-nographic
} option
. @code
{0x01} is equal to pressing
2656 @code
{Control
-a
}. You can select a different character from the ascii
2657 control keys where
1 through
26 map to Control
-a through Control
-z
. For
2658 instance you could use the either of the following to change the escape
2659 character to Control
-t
.
2666 DEF("virtioconsole", HAS_ARG
, QEMU_OPTION_virtiocon
, \
2667 "-virtioconsole c\n" \
2668 " set virtio console\n", QEMU_ARCH_ALL
)
2670 @item
-virtioconsole @
var{c
}
2671 @findex
-virtioconsole
2674 This option is maintained
for backward compatibility
.
2676 Please use @code
{-device virtconsole
} for the
new way of invocation
.
2679 DEF("show-cursor", 0, QEMU_OPTION_show_cursor
, \
2680 "-show-cursor show cursor\n", QEMU_ARCH_ALL
)
2683 @findex
-show
-cursor
2687 DEF("tb-size", HAS_ARG
, QEMU_OPTION_tb_size
, \
2688 "-tb-size n set TB size\n", QEMU_ARCH_ALL
)
2690 @item
-tb
-size @
var{n
}
2695 DEF("incoming", HAS_ARG
, QEMU_OPTION_incoming
, \
2696 "-incoming p prepare for incoming migration, listen on port p\n",
2699 @item
-incoming @
var{port
}
2701 Prepare
for incoming migration
, listen on @
var{port
}.
2704 DEF("nodefaults", 0, QEMU_OPTION_nodefaults
, \
2705 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL
)
2709 Don
't create default devices. Normally, QEMU sets the default devices like serial
2710 port, parallel port, virtual console, monitor device, VGA adapter, floppy and
2711 CD-ROM drive and others. The @code{-nodefaults} option will disable all those
2716 DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
2717 "-chroot dir chroot to dir just before starting the VM\n",
2721 @item -chroot @var{dir}
2723 Immediately before starting guest execution, chroot to the specified
2724 directory. Especially useful in combination with -runas.
2728 DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
2729 "-runas user change to user id user just before starting the VM\n",
2733 @item -runas @var{user}
2735 Immediately before starting guest execution, drop root privileges, switching
2736 to the specified user.
2739 DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
2740 "-prom-env variable=value\n"
2741 " set OpenBIOS nvram variables\n",
2742 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
2744 @item -prom-env @var{variable}=@var{value}
2746 Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
2748 DEF("semihosting", 0, QEMU_OPTION_semihosting,
2749 "-semihosting semihosting mode\n", QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA)
2752 @findex -semihosting
2753 Semihosting mode (ARM, M68K, Xtensa only).
2755 DEF("old-param", 0, QEMU_OPTION_old_param,
2756 "-old-param old param mode\n", QEMU_ARCH_ARM)
2759 @findex -old-param (ARM)
2760 Old param mode (ARM only).
2763 DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
2764 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off
').\n",
2769 Enable Seccomp mode 2 system call filter. 'on
' will enable syscall filtering and 'off
' will
2770 disable it. The default is 'off
'.
2773 DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
2774 "-readconfig <file>\n", QEMU_ARCH_ALL)
2776 @item -readconfig @var{file}
2778 Read device configuration from @var{file}. This approach is useful when you want to spawn
2779 QEMU process with many command line options but you don't want to exceed the command line
2782 DEF("writeconfig", HAS_ARG
, QEMU_OPTION_writeconfig
,
2783 "-writeconfig <file>\n"
2784 " read/write config file\n", QEMU_ARCH_ALL
)
2786 @item
-writeconfig @
var{file
}
2787 @findex
-writeconfig
2788 Write device configuration to @
var{file
}. The @
var{file
} can be either filename to save
2789 command line and device configuration into file or dash @code
{-}) character to print the
2790 output to stdout
. This can be later used as input file
for @code
{-readconfig
} option
.
2792 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig
,
2794 " do not load default config files at startup\n",
2798 @findex
-nodefconfig
2799 Normally QEMU loads configuration files from @
var{sysconfdir
} and @
var{datadir
} at startup
.
2800 The @code
{-nodefconfig
} option will prevent QEMU from loading any of those config files
.
2802 DEF("no-user-config", 0, QEMU_OPTION_nouserconfig
,
2804 " do not load user-provided config files at startup\n",
2807 @item
-no
-user
-config
2808 @findex
-no
-user
-config
2809 The @code
{-no
-user
-config
} option makes QEMU not load any of the user
-provided
2810 config files on @
var{sysconfdir
}, but won
't make it skip the QEMU-provided config
2811 files from @var{datadir}.
2813 DEF("trace", HAS_ARG, QEMU_OPTION_trace,
2814 "-trace [events=<file>][,file=<file>]\n"
2815 " specify tracing options\n",
2818 HXCOMM This line is not accurate, as some sub-options are backend-specific but
2819 HXCOMM HX does not support conditional compilation of text.
2820 @item -trace [events=@var{file}][,file=@var{file}]
2823 Specify tracing options.
2826 @item events=@var{file}
2827 Immediately enable events listed in @var{file}.
2828 The file must contain one event name (as listed in the @var{trace-events} file)
2830 This option is only available if QEMU has been compiled with
2831 either @var{simple} or @var{stderr} tracing backend.
2832 @item file=@var{file}
2833 Log output traces to @var{file}.
2835 This option is only available if QEMU has been compiled with
2836 the @var{simple} tracing backend.
2840 DEF("qtest", HAS_ARG, QEMU_OPTION_qtest,
2841 "-qtest CHR specify tracing options\n",
2844 DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log,
2845 "-qtest-log LOG specify tracing options\n",
2849 DEF("enable-fips", 0, QEMU_OPTION_enablefips,
2850 "-enable-fips enable FIPS 140-2 compliance\n",
2855 @findex -enable-fips
2856 Enable FIPS 140-2 compliance mode.
2859 HXCOMM This is the last statement. Insert new options before this line!