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 [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
842 " [,x509-key-file=<file>][,x509-key-password=<file>]\n"
843 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
844 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6]\n"
845 " [,tls-ciphers=<list>]\n"
846 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
847 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
848 " [,sasl][,password=<secret>][,disable-ticketing]\n"
849 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
850 " [,jpeg-wan-compression=[auto|never|always]]\n"
851 " [,zlib-glz-wan-compression=[auto|never|always]]\n"
852 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
853 " [,agent-mouse=[on|off]][,playback-compression=[on|off]]\n"
854 " [,seamless-migration=[on|off]]\n"
856 " at least one of {port, tls-port} is mandatory\n",
859 @item -spice @var{option}[,@var{option}[,...]]
861 Enable the spice remote desktop protocol. Valid options are
866 Set the TCP port spice is listening on for plaintext channels.
869 Set the IP address spice is listening on. Default is any address.
873 Force using the specified IP version.
875 @item password=<secret>
876 Set the password you need to authenticate.
879 Require that the client use SASL to authenticate with the spice.
880 The exact choice of authentication method used is controlled from the
881 system / user's SASL configuration file
for the
'qemu' service
. This
882 is typically found
in /etc
/sasl2
/qemu
.conf
. If running QEMU as an
883 unprivileged user
, an environment variable SASL_CONF_PATH can be used
884 to make it search alternate locations
for the service config
.
885 While some SASL auth methods can also provide data
encryption (eg GSSAPI
),
886 it is recommended that SASL always be combined with the
'tls' and
887 'x509' settings to enable use of SSL and server certificates
. This
888 ensures a data encryption preventing compromise of authentication
891 @item disable
-ticketing
892 Allow client connects without authentication
.
894 @item disable
-copy
-paste
895 Disable copy paste between the client and the guest
.
898 Set the TCP port spice is listening on
for encrypted channels
.
901 Set the x509 file directory
. Expects same filenames as
-vnc $display
,x509
=$dir
903 @item x509
-key
-file
=<file
>
904 @item x509
-key
-password
=<file
>
905 @item x509
-cert
-file
=<file
>
906 @item x509
-cacert
-file
=<file
>
907 @item x509
-dh
-key
-file
=<file
>
908 The x509 file names can also be configured individually
.
910 @item tls
-ciphers
=<list
>
911 Specify which ciphers to use
.
913 @item tls
-channel
=[main|display|cursor|inputs|record|playback
]
914 @item plaintext
-channel
=[main|display|cursor|inputs|record|playback
]
915 Force specific channel to be used with or without TLS encryption
. The
916 options can be specified multiple times to configure multiple
917 channels
. The special name
"default" can be used to set the
default
918 mode
. For channels which are not explicitly forced into one mode the
919 spice client is allowed to pick tls
/plaintext as he pleases
.
921 @item image
-compression
=[auto_glz|auto_lz|quic|glz|lz|off
]
922 Configure image
compression (lossless
).
925 @item jpeg
-wan
-compression
=[auto|
never|always
]
926 @item zlib
-glz
-wan
-compression
=[auto|
never|always
]
927 Configure wan image
compression (lossy
for slow links
).
930 @item streaming
-video
=[off|all|filter
]
931 Configure video stream detection
. Default is filter
.
933 @item agent
-mouse
=[on|off
]
934 Enable
/disable passing mouse events via vdagent
. Default is on
.
936 @item playback
-compression
=[on|off
]
937 Enable
/disable audio stream
compression (using celt
0.5.1). Default is on
.
939 @item seamless
-migration
=[on|off
]
940 Enable
/disable spice seamless migration
. Default is off
.
945 DEF("portrait", 0, QEMU_OPTION_portrait
,
946 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
951 Rotate graphical output
90 deg
left (only PXA LCD
).
954 DEF("rotate", HAS_ARG
, QEMU_OPTION_rotate
,
955 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
960 Rotate graphical output some deg
left (only PXA LCD
).
963 DEF("vga", HAS_ARG
, QEMU_OPTION_vga
,
964 "-vga [std|cirrus|vmware|qxl|xenfb|none]\n"
965 " select video card type\n", QEMU_ARCH_ALL
)
967 @item
-vga @
var{type
}
969 Select type of VGA card to emulate
. Valid values
for @
var{type
} are
972 Cirrus Logic GD5446 Video card
. All Windows versions starting from
973 Windows
95 should recognize and use
this graphic card
. For optimal
974 performances
, use
16 bit color depth
in the guest and the host OS
.
975 (This one is the
default)
977 Standard VGA card with Bochs VBE extensions
. If your guest OS
978 supports the VESA
2.0 VBE
extensions (e
.g
. Windows XP
) and
if you want
979 to use high resolution
modes (>= 1280x1024x16
) then you should use
982 VMWare SVGA
-II compatible adapter
. Use it
if you have sufficiently
983 recent XFree86
/XOrg server or Windows guest with a driver
for this
986 QXL paravirtual graphic card
. It is VGA
compatible (including VESA
987 2.0 VBE support
). Works best with qxl guest drivers installed though
.
988 Recommended choice when
using the spice protocol
.
994 DEF("full-screen", 0, QEMU_OPTION_full_screen
,
995 "-full-screen start in full screen\n", QEMU_ARCH_ALL
)
999 Start
in full screen
.
1002 DEF("g", 1, QEMU_OPTION_g
,
1003 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
1004 QEMU_ARCH_PPC | QEMU_ARCH_SPARC
)
1006 @item
-g @
var{width
}x@
var{height
}[x@
var{depth
}]
1008 Set the initial graphical resolution and
depth (PPC
, SPARC only
).
1011 DEF("vnc", HAS_ARG
, QEMU_OPTION_vnc
,
1012 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL
)
1014 @item
-vnc @
var{display
}[,@
var{option
}[,@
var{option
}[,...]]]
1016 Normally
, QEMU uses SDL to display the VGA output
. With
this option
,
1017 you can have QEMU listen on VNC display @
var{display
} and redirect the VGA
1018 display over the VNC session
. It is very useful to enable the usb
1019 tablet device when
using this option (option @option
{-usbdevice
1020 tablet
}). When
using the VNC display
, you must use the @option
{-k
}
1021 parameter to set the keyboard layout
if you are not
using en
-us
. Valid
1022 syntax
for the @
var{display
} is
1026 @item @
var{host
}:@
var{d
}
1028 TCP connections will only be allowed from @
var{host
} on display @
var{d
}.
1029 By convention the TCP port is
5900+@
var{d
}. Optionally
, @
var{host
} can
1030 be omitted
in which
case the server will accept connections from any host
.
1032 @item unix
:@
var{path
}
1034 Connections will be allowed over UNIX domain sockets where @
var{path
} is the
1035 location of a unix socket to listen
for connections on
.
1039 VNC is initialized but not started
. The monitor @code
{change
} command
1040 can be used to later start the VNC server
.
1044 Following the @
var{display
} value there may be one or more @
var{option
} flags
1045 separated by commas
. Valid options are
1051 Connect to a listening VNC client via a ``reverse
'' connection
. The
1052 client is specified by the @
var{display
}. For reverse network
1053 connections (@
var{host
}:@
var{d
},@code
{reverse
}), the @
var{d
} argument
1054 is a TCP port number
, not a display number
.
1058 Require that password based authentication is used
for client connections
.
1060 The password must be set separately
using the @code
{set_password
} command
in
1061 the @ref
{pcsys_monitor
}. The syntax to change your password is
:
1062 @code
{set_password
<protocol
> <password
>} where
<protocol
> could be either
1065 If you would like to change
<protocol
> password expiration
, you should use
1066 @code
{expire_password
<protocol
> <expiration
-time
>} where expiration time could
1067 be one of the following options
: now
, never, +seconds or UNIX time of
1068 expiration
, e
.g
. +60 to make password expire
in 60 seconds
, or
1335196800
1069 to make password expire on
"Mon Apr 23 12:00:00 EDT 2012" (UNIX time
for this
1072 You can also use keywords
"now" or
"never" for the expiration time to
1073 allow
<protocol
> password to expire immediately or
never expire
.
1077 Require that client use TLS when communicating with the VNC server
. This
1078 uses anonymous TLS credentials so is susceptible to a man
-in-the
-middle
1079 attack
. It is recommended that
this option be combined with either the
1080 @option
{x509
} or @option
{x509verify
} options
.
1082 @item x509
=@
var{/path
/to
/certificate
/dir
}
1084 Valid
if @option
{tls
} is specified
. Require that x509 credentials are used
1085 for negotiating the TLS session
. The server will send its x509 certificate
1086 to the client
. It is recommended that a password be set on the VNC server
1087 to provide authentication of the client when
this is used
. The path following
1088 this option specifies where the x509 certificates are to be loaded from
.
1089 See the @ref
{vnc_security
} section
for details on generating certificates
.
1091 @item x509verify
=@
var{/path
/to
/certificate
/dir
}
1093 Valid
if @option
{tls
} is specified
. Require that x509 credentials are used
1094 for negotiating the TLS session
. The server will send its x509 certificate
1095 to the client
, and request that the client send its own x509 certificate
.
1096 The server will validate the client
's certificate against the CA certificate,
1097 and reject clients when validation fails. If the certificate authority is
1098 trusted, this is a sufficient authentication mechanism. You may still wish
1099 to set a password on the VNC server as a second authentication layer. The
1100 path following this option specifies where the x509 certificates are to
1101 be loaded from. See the @ref{vnc_security} section for details on generating
1106 Require that the client use SASL to authenticate with the VNC server.
1107 The exact choice of authentication method used is controlled from the
1108 system / user's SASL configuration file
for the
'qemu' service
. This
1109 is typically found
in /etc
/sasl2
/qemu
.conf
. If running QEMU as an
1110 unprivileged user
, an environment variable SASL_CONF_PATH can be used
1111 to make it search alternate locations
for the service config
.
1112 While some SASL auth methods can also provide data
encryption (eg GSSAPI
),
1113 it is recommended that SASL always be combined with the
'tls' and
1114 'x509' settings to enable use of SSL and server certificates
. This
1115 ensures a data encryption preventing compromise of authentication
1116 credentials
. See the @ref
{vnc_security
} section
for details on
using
1117 SASL authentication
.
1121 Turn on access control lists
for checking of the x509 client certificate
1122 and SASL party
. For x509 certs
, the ACL check is made against the
1123 certificate
's distinguished name. This is something that looks like
1124 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1125 made against the username, which depending on the SASL plugin, may
1126 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1127 When the @option{acl} flag is set, the initial access list will be
1128 empty, with a @code{deny} policy. Thus no one will be allowed to
1129 use the VNC server until the ACLs have been loaded. This can be
1130 achieved using the @code{acl} monitor command.
1134 Enable lossy compression methods (gradient, JPEG, ...). If this
1135 option is set, VNC client may receive lossy framebuffer updates
1136 depending on its encoding settings. Enabling this option can save
1137 a lot of bandwidth at the expense of quality.
1141 Disable adaptive encodings. Adaptive encodings are enabled by default.
1142 An adaptive encoding will try to detect frequently updated screen regions,
1143 and send updates in these regions using a lossy encoding (like JPEG).
1144 This can be really helpful to save bandwidth when playing videos. Disabling
1145 adaptive encodings allows to restore the original static behavior of encodings
1148 @item share=[allow-exclusive|force-shared|ignore]
1150 Set display sharing policy. 'allow
-exclusive
' allows clients to ask
1151 for exclusive access. As suggested by the rfb spec this is
1152 implemented by dropping other connections. Connecting multiple
1153 clients in parallel requires all clients asking for a shared session
1154 (vncviewer: -shared switch). This is the default. 'force
-shared
'
1155 disables exclusive client access. Useful for shared desktop sessions,
1156 where you don't want someone forgetting specify
-shared disconnect
1157 everybody
else. 'ignore' completely ignores the shared flag and
1158 allows everybody connect unconditionally
. Doesn
't conform to the rfb
1159 spec but is traditional QEMU behavior.
1168 ARCHHEADING(, QEMU_ARCH_I386)
1170 ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1175 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1176 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1181 Use it when installing Windows 2000 to avoid a disk full bug. After
1182 Windows 2000 is installed, you no longer need this option (this option
1183 slows down the IDE transfers).
1186 HXCOMM Deprecated by -rtc
1187 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1189 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1190 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1193 @item -no-fd-bootchk
1194 @findex -no-fd-bootchk
1195 Disable boot signature checking for floppy disks in Bochs BIOS. It may
1196 be needed to boot from old floppy disks.
1197 TODO: check reference to Bochs BIOS.
1200 DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1201 "-no-acpi disable ACPI\n", QEMU_ARCH_I386)
1205 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1206 it if your guest OS complains about ACPI problems (PC target machine
1210 DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1211 "-no-hpet disable HPET\n", QEMU_ARCH_I386)
1215 Disable HPET support.
1218 DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1219 "-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"
1220 " ACPI table description\n", QEMU_ARCH_I386)
1222 @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}]...]
1224 Add ACPI table with specified header fields and context from specified files.
1225 For file=, take whole ACPI table from the specified files, including all
1226 ACPI headers (possible overridden by other options).
1227 For data=, only data
1228 portion of the table is used, all header information is specified in the
1232 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1233 "-smbios file=binary\n"
1234 " load SMBIOS entry from binary file\n"
1235 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1236 " specify SMBIOS type 0 fields\n"
1237 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1238 " [,uuid=uuid][,sku=str][,family=str]\n"
1239 " specify SMBIOS type 1 fields\n", QEMU_ARCH_I386)
1241 @item -smbios file=@var{binary}
1243 Load SMBIOS entry from binary file.
1245 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}]
1247 Specify SMBIOS type 0 fields
1249 @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}]
1250 Specify SMBIOS type 1 fields
1258 DEFHEADING(Network options:)
1263 HXCOMM Legacy slirp options (now moved to -net user):
1265 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1266 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1267 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1269 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1273 DEF("net", HAS_ARG, QEMU_OPTION_net,
1274 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
1275 " create a new Network Interface Card and connect it to VLAN 'n
'\n"
1277 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=on|off]\n"
1278 " [,hostname=host][,dhcpstart=addr][,dns=addr][,tftp=dir][,bootfile=f]\n"
1279 " [,hostfwd=rule][,guestfwd=rule]"
1281 "[,smb=dir[,smbserver=addr]]\n"
1283 " connect the user mode network stack to VLAN 'n
', configure its\n"
1284 " DHCP server and enabled optional services\n"
1287 "-net tap[,vlan=n][,name=str],ifname=name\n"
1288 " connect the host TAP network interface to VLAN 'n
'\n"
1290 "-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"
1291 " connect the host TAP network interface to VLAN 'n
' \n"
1292 " use network scripts 'file
' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1293 " to configure it and 'dfile
' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1294 " to deconfigure it\n"
1295 " use '[down
]script
=no
' to disable script execution\n"
1296 " use network helper 'helper
' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1298 " use 'fd
=h
' to connect to an already opened TAP interface\n"
1299 " use 'sndbuf
=nbytes
' to limit the size of the send buffer (the\n"
1300 " default is disabled 'sndbuf
=0' to enable flow control set 'sndbuf
=1048576')\n"
1301 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1302 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1303 " use vhost=on to enable experimental in kernel accelerator\n"
1304 " (only has effect for virtio guests which use MSIX)\n"
1305 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1306 " use 'vhostfd
=h
' to connect to an already opened vhost net device\n"
1307 "-net bridge[,vlan=n][,name=str][,br=bridge][,helper=helper]\n"
1308 " connects a host TAP network interface to a host bridge device 'br
'\n"
1309 " (default=" DEFAULT_BRIDGE_INTERFACE ") using the program 'helper
'\n"
1310 " (default=" DEFAULT_BRIDGE_HELPER ")\n"
1312 "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n"
1313 " connect the vlan 'n
' to another VLAN using a socket connection\n"
1314 "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1315 " connect the vlan 'n
' to multicast maddr and port\n"
1316 " use 'localaddr
=addr
' to specify the host address to send packets from\n"
1317 "-net socket[,vlan=n][,name=str][,fd=h][,udp=host:port][,localaddr=host:port]\n"
1318 " connect the vlan 'n
' to another VLAN using an UDP tunnel\n"
1320 "-net vde[,vlan=n][,name=str][,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1321 " connect the vlan 'n
' to port 'n
' of a vde switch running\n"
1322 " on host and listening for incoming connections on 'socketpath
'.\n"
1323 " Use group 'groupname
' and mode 'octalmode
' to change default\n"
1324 " ownership and permissions for communication port.\n"
1326 "-net dump[,vlan=n][,file=f][,len=n]\n"
1327 " dump traffic on vlan 'n
' to file 'f
' (max n bytes per packet)\n"
1328 "-net none use it alone to have zero network devices. If no -net option\n"
1329 " is provided, the default is '-net nic
-net user
'\n", QEMU_ARCH_ALL)
1330 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1340 "socket],id=str[,option][,option][,...]\n", QEMU_ARCH_ALL)
1342 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1344 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1345 = 0 is the default). The NIC is an e1000 by default on the PC
1346 target. Optionally, the MAC address can be changed to @var{mac}, the
1347 device address set to @var{addr} (PCI cards only),
1348 and a @var{name} can be assigned for use in monitor commands.
1349 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1350 that the card should have; this option currently only affects virtio cards; set
1351 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1352 NIC is created. QEMU can emulate several different models of network card.
1353 Valid values for @var{type} are
1354 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1355 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1356 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1357 Not all devices are supported on all targets. Use -net nic,model=?
1358 for a list of available devices for your target.
1360 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
1361 @item -net user[,@var{option}][,@var{option}][,...]
1362 Use the user mode network stack which requires no administrator
1363 privilege to run. Valid options are:
1367 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1370 @item name=@var{name}
1371 Assign symbolic name for use in monitor commands.
1373 @item net=@var{addr}[/@var{mask}]
1374 Set IP network address the guest will see. Optionally specify the netmask,
1375 either in the form a.b.c.d or as number of valid top-most bits. Default is
1378 @item host=@var{addr}
1379 Specify the guest-visible address of the host. Default is the 2nd IP in the
1380 guest network, i.e. x.x.x.2.
1382 @item restrict=on|off
1383 If this option is enabled, the guest will be isolated, i.e. it will not be
1384 able to contact the host and no guest IP packets will be routed over the host
1385 to the outside. This option does not affect any explicitly set forwarding rules.
1387 @item hostname=@var{name}
1388 Specifies the client hostname reported by the builtin DHCP server.
1390 @item dhcpstart=@var{addr}
1391 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1392 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1394 @item dns=@var{addr}
1395 Specify the guest-visible address of the virtual nameserver. The address must
1396 be different from the host address. Default is the 3rd IP in the guest network,
1399 @item tftp=@var{dir}
1400 When using the user mode network stack, activate a built-in TFTP
1401 server. The files in @var{dir} will be exposed as the root of a TFTP server.
1402 The TFTP client on the guest must be configured in binary mode (use the command
1403 @code{bin} of the Unix TFTP client).
1405 @item bootfile=@var{file}
1406 When using the user mode network stack, broadcast @var{file} as the BOOTP
1407 filename. In conjunction with @option{tftp}, this can be used to network boot
1408 a guest from a local directory.
1410 Example (using pxelinux):
1412 qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1415 @item smb=@var{dir}[,smbserver=@var{addr}]
1416 When using the user mode network stack, activate a built-in SMB
1417 server so that Windows OSes can access to the host files in @file{@var{dir}}
1418 transparently. The IP address of the SMB server can be set to @var{addr}. By
1419 default the 4th IP in the guest network is used, i.e. x.x.x.4.
1421 In the guest Windows OS, the line:
1425 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1426 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1428 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
1430 Note that a SAMBA server must be installed on the host OS.
1431 QEMU was tested successfully with smbd versions from Red Hat 9,
1432 Fedora Core 3 and OpenSUSE 11.x.
1434 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1435 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1436 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1437 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1438 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1439 be bound to a specific host interface. If no connection type is set, TCP is
1440 used. This option can be given multiple times.
1442 For example, to redirect host X11 connection from screen 1 to guest
1443 screen 0, use the following:
1447 qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1448 # this host xterm should open in the guest X11 server
1452 To redirect telnet connections from host port 5555 to telnet port on
1453 the guest, use the following:
1457 qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
1458 telnet localhost 5555
1461 Then when you use on the host @code{telnet localhost 5555}, you
1462 connect to the guest telnet server.
1464 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1465 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
1466 Forward guest TCP connections to the IP address @var{server} on port @var{port}
1467 to the character device @var{dev} or to a program executed by @var{cmd:command}
1468 which gets spawned for each connection. This option can be given multiple times.
1470 You can either use a chardev directly and have that one used throughout QEMU's
1471 lifetime
, like
in the following example
:
1474 # open
10.10.1.1:4321 on bootup
, connect
10.0.2.100:1234 to it whenever
1475 # the guest accesses it
1476 qemu
-net user
,guestfwd
=tcp
:10.0.2.100:1234-tcp
:10.10.1.1:4321 [...]
1479 Or you can execute a command on every TCP connection established by the guest
,
1480 so that QEMU behaves similar to an inetd process
for that virtual server
:
1483 # call
"netcat 10.10.1.1 4321" on every TCP connection to
10.0.2.100:1234
1484 # and connect the TCP stream to its stdin
/stdout
1485 qemu
-net
'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
1490 Note
: Legacy stand
-alone options
-tftp
, -bootp
, -smb and
-redir are still
1491 processed and applied to
-net user
. Mixing them with the
new configuration
1492 syntax gives undefined results
. Their use
for new applications is discouraged
1493 as they will be removed from future versions
.
1495 @item
-netdev tap
,id
=@
var{id
}[,fd
=@
var{h
}][,ifname
=@
var{name
}][,script
=@
var{file
}][,downscript
=@
var{dfile
}][,helper
=@
var{helper
}]
1496 @item
-net tap
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}][,ifname
=@
var{name
}][,script
=@
var{file
}][,downscript
=@
var{dfile
}][,helper
=@
var{helper
}]
1497 Connect the host TAP network
interface @
var{name
} to VLAN @
var{n
}.
1499 Use the network script @
var{file
} to configure it and the network script
1500 @
var{dfile
} to deconfigure it
. If @
var{name
} is not provided
, the OS
1501 automatically provides one
. The
default network configure script is
1502 @file
{/etc
/qemu
-ifup
} and the
default network deconfigure script is
1503 @file
{/etc
/qemu
-ifdown
}. Use @option
{script
=no
} or @option
{downscript
=no
}
1504 to disable script execution
.
1506 If running QEMU as an unprivileged user
, use the network helper
1507 @
var{helper
} to configure the TAP
interface. The
default network
1508 helper executable is @file
{/usr
/local
/libexec
/qemu
-bridge
-helper
}.
1510 @option
{fd
}=@
var{h
} can be used to specify the handle of an already
1511 opened host TAP
interface.
1516 #launch a QEMU instance with the
default network script
1517 qemu
-system
-i386 linux
.img
-net nic
-net tap
1521 #launch a QEMU instance with two NICs
, each one connected
1523 qemu
-system
-i386 linux
.img \
1524 -net nic
,vlan
=0 -net tap
,vlan
=0,ifname
=tap0 \
1525 -net nic
,vlan
=1 -net tap
,vlan
=1,ifname
=tap1
1529 #launch a QEMU instance with the
default network helper to
1530 #connect a TAP device to bridge br0
1531 qemu
-system
-i386 linux
.img \
1532 -net nic
-net tap
,"helper=/usr/local/libexec/qemu-bridge-helper"
1535 @item
-netdev bridge
,id
=@
var{id
}[,br
=@
var{bridge
}][,helper
=@
var{helper
}]
1536 @item
-net bridge
[,vlan
=@
var{n
}][,name
=@
var{name
}][,br
=@
var{bridge
}][,helper
=@
var{helper
}]
1537 Connect a host TAP network
interface to a host bridge device
.
1539 Use the network helper @
var{helper
} to configure the TAP
interface and
1540 attach it to the bridge
. The
default network helper executable is
1541 @file
{/usr
/local
/libexec
/qemu
-bridge
-helper
} and the
default bridge
1542 device is @file
{br0
}.
1547 #launch a QEMU instance with the
default network helper to
1548 #connect a TAP device to bridge br0
1549 qemu
-system
-i386 linux
.img
-net bridge
-net nic
,model
=virtio
1553 #launch a QEMU instance with the
default network helper to
1554 #connect a TAP device to bridge qemubr0
1555 qemu
-system
-i386 linux
.img
-net bridge
,br
=qemubr0
-net nic
,model
=virtio
1558 @item
-netdev socket
,id
=@
var{id
}[,fd
=@
var{h
}][,listen
=[@
var{host
}]:@
var{port
}][,connect
=@
var{host
}:@
var{port
}]
1559 @item
-net socket
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}] [,listen
=[@
var{host
}]:@
var{port
}][,connect
=@
var{host
}:@
var{port
}]
1561 Connect the VLAN @
var{n
} to a remote VLAN
in another QEMU virtual
1562 machine
using a TCP socket connection
. If @option
{listen
} is
1563 specified
, QEMU waits
for incoming connections on @
var{port
}
1564 (@
var{host
} is optional
). @option
{connect
} is used to connect to
1565 another QEMU instance
using the @option
{listen
} option
. @option
{fd
}=@
var{h
}
1566 specifies an already opened TCP socket
.
1570 # launch a first QEMU instance
1571 qemu
-system
-i386 linux
.img \
1572 -net nic
,macaddr
=52:54:00:12:34:56 \
1573 -net socket
,listen
=:1234
1574 # connect the VLAN
0 of
this instance to the VLAN
0
1575 # of the first instance
1576 qemu
-system
-i386 linux
.img \
1577 -net nic
,macaddr
=52:54:00:12:34:57 \
1578 -net socket
,connect
=127.0.0.1:1234
1581 @item
-netdev socket
,id
=@
var{id
}[,fd
=@
var{h
}][,mcast
=@
var{maddr
}:@
var{port
}[,localaddr
=@
var{addr
}]]
1582 @item
-net socket
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}][,mcast
=@
var{maddr
}:@
var{port
}[,localaddr
=@
var{addr
}]]
1584 Create a VLAN @
var{n
} shared with another QEMU virtual
1585 machines
using a UDP multicast socket
, effectively making a bus
for
1586 every QEMU with same multicast address @
var{maddr
} and @
var{port
}.
1590 Several QEMU can be running on different hosts and share same
bus (assuming
1591 correct multicast setup
for these hosts
).
1593 mcast support is compatible with User Mode
Linux (argument @option
{eth@
var{N
}=mcast
}), see
1594 @url
{http
://user-mode-linux.sf.net}.
1596 Use @option
{fd
=h
} to specify an already opened UDP multicast socket
.
1601 # launch one QEMU instance
1602 qemu
-system
-i386 linux
.img \
1603 -net nic
,macaddr
=52:54:00:12:34:56 \
1604 -net socket
,mcast
=230.0.0.1:1234
1605 # launch another QEMU instance on same
"bus"
1606 qemu
-system
-i386 linux
.img \
1607 -net nic
,macaddr
=52:54:00:12:34:57 \
1608 -net socket
,mcast
=230.0.0.1:1234
1609 # launch yet another QEMU instance on same
"bus"
1610 qemu
-system
-i386 linux
.img \
1611 -net nic
,macaddr
=52:54:00:12:34:58 \
1612 -net socket
,mcast
=230.0.0.1:1234
1615 Example (User Mode Linux compat
.):
1617 # launch QEMU
instance (note mcast address selected
1619 qemu-system-i386 linux.img \
1620 -net nic,macaddr=52:54:00:12:34:56 \
1621 -net socket,mcast=239.192.168.1:1102
1623 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
1626 Example (send packets from host's
1.2.3.4):
1628 qemu
-system
-i386 linux
.img \
1629 -net nic
,macaddr
=52:54:00:12:34:56 \
1630 -net socket
,mcast
=239.192.168.1:1102,localaddr
=1.2.3.4
1633 @item
-netdev vde
,id
=@
var{id
}[,sock
=@
var{socketpath
}][,port
=@
var{n
}][,group
=@
var{groupname
}][,mode
=@
var{octalmode
}]
1634 @item
-net vde
[,vlan
=@
var{n
}][,name
=@
var{name
}][,sock
=@
var{socketpath
}] [,port
=@
var{n
}][,group
=@
var{groupname
}][,mode
=@
var{octalmode
}]
1635 Connect VLAN @
var{n
} to PORT @
var{n
} of a vde
switch running on host and
1636 listening
for incoming connections on @
var{socketpath
}. Use GROUP @
var{groupname
}
1637 and MODE @
var{octalmode
} to change
default ownership and permissions
for
1638 communication port
. This option is only available
if QEMU has been compiled
1639 with vde support enabled
.
1644 vde_switch
-F
-sock
/tmp
/myswitch
1645 # launch QEMU instance
1646 qemu
-system
-i386 linux
.img
-net nic
-net vde
,sock
=/tmp
/myswitch
1649 @item
-net dump
[,vlan
=@
var{n
}][,file
=@
var{file
}][,len
=@
var{len
}]
1650 Dump network traffic on VLAN @
var{n
} to file @
var{file
} (@file
{qemu
-vlan0
.pcap
} by
default).
1651 At most @
var{len
} bytes (64k by
default) per packet are stored
. The file format is
1652 libpcap
, so it can be analyzed with tools such as tcpdump or Wireshark
.
1655 Indicate that no network devices should be configured
. It is used to
1656 override the
default configuration (@option
{-net nic
-net user
}) which
1657 is activated
if no @option
{-net
} options are provided
.
1664 DEFHEADING(Character device options
:)
1666 DEF("chardev", HAS_ARG
, QEMU_OPTION_chardev
,
1667 "-chardev null,id=id[,mux=on|off]\n"
1668 "-chardev socket,id=id[,host=host],port=host[,to=to][,ipv4][,ipv6][,nodelay]\n"
1669 " [,server][,nowait][,telnet][,mux=on|off] (tcp)\n"
1670 "-chardev socket,id=id,path=path[,server][,nowait][,telnet],[mux=on|off] (unix)\n"
1671 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
1672 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
1673 "-chardev msmouse,id=id[,mux=on|off]\n"
1674 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
1676 "-chardev file,id=id,path=path[,mux=on|off]\n"
1677 "-chardev pipe,id=id,path=path[,mux=on|off]\n"
1679 "-chardev console,id=id[,mux=on|off]\n"
1680 "-chardev serial,id=id,path=path[,mux=on|off]\n"
1682 "-chardev pty,id=id[,mux=on|off]\n"
1683 "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n"
1685 #ifdef CONFIG_BRLAPI
1686 "-chardev braille,id=id[,mux=on|off]\n"
1688 #
if defined(__linux__
) ||
defined(__sun__
) ||
defined(__FreeBSD__
) \
1689 ||
defined(__NetBSD__
) ||
defined(__OpenBSD__
) ||
defined(__DragonFly__
)
1690 "-chardev tty,id=id,path=path[,mux=on|off]\n"
1692 #
if defined(__linux__
) ||
defined(__FreeBSD__
) ||
defined(__DragonFly__
)
1693 "-chardev parport,id=id,path=path[,mux=on|off]\n"
1695 #
if defined(CONFIG_SPICE
)
1696 "-chardev spicevmc,id=id,name=name[,debug=debug]\n"
1703 The general form of a character device option is
:
1706 @item
-chardev @
var{backend
} ,id
=@
var{id
} [,mux
=on|off
] [,@
var{options
}]
1724 The specific backend will determine the applicable options
.
1726 All devices must have an id
, which can be any string up to
127 characters long
.
1727 It is used to uniquely identify
this device
in other command line directives
.
1729 A character device may be used
in multiplexing mode by multiple front
-ends
.
1730 The key sequence of @key
{Control
-a
} and @key
{c
} will rotate the input focus
1731 between attached front
-ends
. Specify @option
{mux
=on
} to enable
this mode
.
1733 Options to each backend are described below
.
1735 @item
-chardev
null ,id
=@
var{id
}
1736 A void device
. This device will not emit any data
, and will drop any data it
1737 receives
. The
null backend does not take any options
.
1739 @item
-chardev socket
,id
=@
var{id
} [@
var{TCP options
} or @
var{unix options
}] [,server
] [,nowait
] [,telnet
]
1741 Create a two
-way stream socket
, which can be either a TCP or a unix socket
. A
1742 unix socket will be created
if @option
{path
} is specified
. Behaviour is
1743 undefined
if TCP options are specified
for a unix socket
.
1745 @option
{server
} specifies that the socket shall be a listening socket
.
1747 @option
{nowait
} specifies that QEMU should not block waiting
for a client to
1748 connect to a listening socket
.
1750 @option
{telnet
} specifies that traffic on the socket should interpret telnet
1753 TCP and unix socket options are given below
:
1757 @item TCP options
: port
=@
var{port
} [,host
=@
var{host
}] [,to
=@
var{to
}] [,ipv4
] [,ipv6
] [,nodelay
]
1759 @option
{host
} for a listening socket specifies the local address to be bound
.
1760 For a connecting socket species the remote host to connect to
. @option
{host
} is
1761 optional
for listening sockets
. If not specified it defaults to @code
{0.0.0.0}.
1763 @option
{port
} for a listening socket specifies the local port to be bound
. For a
1764 connecting socket specifies the port on the remote host to connect to
.
1765 @option
{port
} can be given as either a port number or a service name
.
1766 @option
{port
} is required
.
1768 @option
{to
} is only relevant to listening sockets
. If it is specified
, and
1769 @option
{port
} cannot be bound
, QEMU will attempt to bind to subsequent ports up
1770 to and including @option
{to
} until it succeeds
. @option
{to
} must be specified
1773 @option
{ipv4
} and @option
{ipv6
} specify that either IPv4 or IPv6 must be used
.
1774 If neither is specified the socket may use either protocol
.
1776 @option
{nodelay
} disables the Nagle algorithm
.
1778 @item unix options
: path
=@
var{path
}
1780 @option
{path
} specifies the local path of the unix socket
. @option
{path
} is
1785 @item
-chardev udp
,id
=@
var{id
} [,host
=@
var{host
}] ,port
=@
var{port
} [,localaddr
=@
var{localaddr
}] [,localport
=@
var{localport
}] [,ipv4
] [,ipv6
]
1787 Sends all traffic from the guest to a remote host over UDP
.
1789 @option
{host
} specifies the remote host to connect to
. If not specified it
1790 defaults to @code
{localhost
}.
1792 @option
{port
} specifies the port on the remote host to connect to
. @option
{port
}
1795 @option
{localaddr
} specifies the local address to bind to
. If not specified it
1796 defaults to @code
{0.0.0.0}.
1798 @option
{localport
} specifies the local port to bind to
. If not specified any
1799 available local port will be used
.
1801 @option
{ipv4
} and @option
{ipv6
} specify that either IPv4 or IPv6 must be used
.
1802 If neither is specified the device may use either protocol
.
1804 @item
-chardev msmouse
,id
=@
var{id
}
1806 Forward QEMU
's emulated msmouse events to the guest. @option{msmouse} does not
1809 @item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
1811 Connect to a QEMU text console. @option{vc} may optionally be given a specific
1814 @option{width} and @option{height} specify the width and height respectively of
1815 the console, in pixels.
1817 @option{cols} and @option{rows} specify that the console be sized to fit a text
1818 console with the given dimensions.
1820 @item -chardev file ,id=@var{id} ,path=@var{path}
1822 Log all traffic received from the guest to a file.
1824 @option{path} specifies the path of the file to be opened. This file will be
1825 created if it does not already exist, and overwritten if it does. @option{path}
1828 @item -chardev pipe ,id=@var{id} ,path=@var{path}
1830 Create a two-way connection to the guest. The behaviour differs slightly between
1831 Windows hosts and other hosts:
1833 On Windows, a single duplex pipe will be created at
1834 @file{\\.pipe\@option{path}}.
1836 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
1837 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
1838 received by the guest. Data written by the guest can be read from
1839 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
1842 @option{path} forms part of the pipe path as described above. @option{path} is
1845 @item -chardev console ,id=@var{id}
1847 Send traffic from the guest to QEMU's standard output
. @option
{console
} does not
1850 @option
{console
} is only available on Windows hosts
.
1852 @item
-chardev serial
,id
=@
var{id
} ,path
=@option
{path
}
1854 Send traffic from the guest to a serial device on the host
.
1857 only available on Windows hosts
.
1859 @option
{path
} specifies the name of the serial device to open
.
1861 @item
-chardev pty
,id
=@
var{id
}
1863 Create a
new pseudo
-terminal on the host and connect to it
. @option
{pty
} does
1864 not take any options
.
1866 @option
{pty
} is not available on Windows hosts
.
1868 @item
-chardev stdio
,id
=@
var{id
} [,signal
=on|off
]
1869 Connect to standard input and standard output of the QEMU process
.
1871 @option
{signal
} controls
if signals are enabled on the terminal
, that includes
1872 exiting QEMU with the key sequence @key
{Control
-c
}. This option is enabled by
1873 default, use @option
{signal
=off
} to disable it
.
1875 @option
{stdio
} is not available on Windows hosts
.
1877 @item
-chardev braille
,id
=@
var{id
}
1879 Connect to a local BrlAPI server
. @option
{braille
} does not take any options
.
1881 @item
-chardev tty
,id
=@
var{id
} ,path
=@
var{path
}
1883 Connect to a local tty device
.
1885 @option
{tty
} is only available on Linux
, Sun
, FreeBSD
, NetBSD
, OpenBSD and
1888 @option
{path
} specifies the path to the tty
. @option
{path
} is required
.
1890 @item
-chardev parport
,id
=@
var{id
} ,path
=@
var{path
}
1892 @option
{parport
} is only available on Linux
, FreeBSD and DragonFlyBSD hosts
.
1894 Connect to a local parallel port
.
1896 @option
{path
} specifies the path to the parallel port device
. @option
{path
} is
1899 @item
-chardev spicevmc
,id
=@
var{id
} ,debug
=@
var{debug
}, name
=@
var{name
}
1901 @option
{spicevmc
} is only available when spice support is built
in.
1903 @option
{debug
} debug level
for spicevmc
1905 @option
{name
} name of spice channel to connect to
1907 Connect to a spice virtual machine channel
, such as vdiport
.
1915 DEFHEADING(Device URL Syntax
:)
1917 In addition to
using normal file images
for the emulated storage devices
,
1918 QEMU can also use networked resources such as iSCSI devices
. These are
1919 specified
using a special URL syntax
.
1923 iSCSI support allows QEMU to access iSCSI resources directly and use as
1924 images
for the guest storage
. Both disk and cdrom images are supported
.
1926 Syntax
for specifying iSCSI LUNs is
1927 ``iscsi
://<target-ip>[:<port>]/<target-iqn>/<lun>''
1929 By
default qemu will use the iSCSI initiator
-name
1930 'iqn.2008-11.org.linux-kvm[:<name>]' but
this can also be set from the command
1931 line or a configuration file
.
1934 Example (without authentication
):
1936 qemu
-system
-i386
-iscsi initiator
-name
=iqn
.2001-04.com
.example
:my
-initiator \
1937 -cdrom iscsi
://192.0.2.1/iqn.2001-04.com.example/2 \
1938 -drive file
=iscsi
://192.0.2.1/iqn.2001-04.com.example/1
1941 Example (CHAP username
/password via URL
):
1943 qemu
-system
-i386
-drive file
=iscsi
://user%password@@192.0.2.1/iqn.2001-04.com.example/1
1946 Example (CHAP username
/password via environment variables
):
1948 LIBISCSI_CHAP_USERNAME
="user" \
1949 LIBISCSI_CHAP_PASSWORD
="password" \
1950 qemu
-system
-i386
-drive file
=iscsi
://192.0.2.1/iqn.2001-04.com.example/1
1953 iSCSI support is an optional feature of QEMU and only available when
1954 compiled and linked against libiscsi
.
1956 DEF("iscsi", HAS_ARG
, QEMU_OPTION_iscsi
,
1957 "-iscsi [user=user][,password=password]\n"
1958 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
1959 " [,initiator-name=iqn]\n"
1960 " iSCSI session parameters\n", QEMU_ARCH_ALL
)
1963 iSCSI parameters such as username and password can also be specified via
1964 a configuration file
. See qemu
-doc
for more information and examples
.
1967 QEMU supports
NBD (Network Block Devices
) both
using TCP protocol as well
1968 as Unix Domain Sockets
.
1970 Syntax
for specifying a NBD device
using TCP
1971 ``nbd
:<server
-ip
>:<port
>[:exportname
=<export
>]''
1973 Syntax
for specifying a NBD device
using Unix Domain Sockets
1974 ``nbd
:unix
:<domain
-socket
>[:exportname
=<export
>]''
1979 qemu
-system
-i386
--drive file
=nbd
:192.0.2.1:30000
1982 Example
for Unix Domain Sockets
1984 qemu
-system
-i386
--drive file
=nbd
:unix
:/tmp
/nbd
-socket
1988 Sheepdog is a distributed storage system
for QEMU
.
1989 QEMU supports
using either local sheepdog devices or remote networked
1992 Syntax
for specifying a sheepdog device
1994 ``sheepdog
:<vdiname
>''
1996 ``sheepdog
:<vdiname
>:<snapid
>''
1998 ``sheepdog
:<vdiname
>:<tag
>''
2000 ``sheepdog
:<host
>:<port
>:<vdiname
>''
2002 ``sheepdog
:<host
>:<port
>:<vdiname
>:<snapid
>''
2004 ``sheepdog
:<host
>:<port
>:<vdiname
>:<tag
>''
2009 qemu
-system
-i386
--drive file
=sheepdog
:192.0.2.1:30000:MyVirtualMachine
2012 See also @url
{http
://http://www.osrg.net/sheepdog/}.
2017 DEFHEADING(Bluetooth(R
) options
:)
2019 DEF("bt", HAS_ARG
, QEMU_OPTION_bt
, \
2020 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \
2021 "-bt hci,host[:id]\n" \
2022 " use host's HCI with the given name\n" \
2023 "-bt hci[,vlan=n]\n" \
2024 " emulate a standard HCI in virtual scatternet 'n'\n" \
2025 "-bt vhci[,vlan=n]\n" \
2026 " add host computer to virtual scatternet 'n' using VHCI\n" \
2027 "-bt device:dev[,vlan=n]\n" \
2028 " emulate a bluetooth device 'dev' in scatternet 'n'\n",
2035 Defines the
function of the corresponding Bluetooth HCI
. -bt options
2036 are matched with the HCIs present
in the chosen machine type
. For
2037 example when emulating a machine with only one HCI built into it
, only
2038 the first @code
{-bt hci
[...]} option is valid and defines the HCI
's
2039 logic. The Transport Layer is decided by the machine type. Currently
2040 the machines @code{n800} and @code{n810} have one HCI and all other
2044 The following three types are recognized:
2048 (default) The corresponding Bluetooth HCI assumes no internal logic
2049 and will not respond to any HCI commands or emit events.
2051 @item -bt hci,host[:@var{id}]
2052 (@code{bluez} only) The corresponding HCI passes commands / events
2053 to / from the physical HCI identified by the name @var{id} (default:
2054 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
2055 capable systems like Linux.
2057 @item -bt hci[,vlan=@var{n}]
2058 Add a virtual, standard HCI that will participate in the Bluetooth
2059 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
2060 VLANs, devices inside a bluetooth network @var{n} can only communicate
2061 with other devices in the same network (scatternet).
2064 @item -bt vhci[,vlan=@var{n}]
2065 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2066 to the host bluetooth stack instead of to the emulated target. This
2067 allows the host and target machines to participate in a common scatternet
2068 and communicate. Requires the Linux @code{vhci} driver installed. Can
2069 be used as following:
2072 qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2075 @item -bt device:@var{dev}[,vlan=@var{n}]
2076 Emulate a bluetooth device @var{dev} and place it in network @var{n}
2077 (default @code{0}). QEMU can only emulate one type of bluetooth devices
2082 Virtual wireless keyboard implementing the HIDP bluetooth profile.
2089 DEFHEADING(Linux/Multiboot boot specific:)
2092 When using these options, you can use a given Linux or Multiboot
2093 kernel without installing it in the disk image. It can be useful
2094 for easier testing of various kernels.
2099 DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
2100 "-kernel bzImage use 'bzImage
' as kernel image\n", QEMU_ARCH_ALL)
2102 @item -kernel @var{bzImage}
2104 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2105 or in multiboot format.
2108 DEF("append", HAS_ARG, QEMU_OPTION_append, \
2109 "-append cmdline use 'cmdline
' as kernel command line\n", QEMU_ARCH_ALL)
2111 @item -append @var{cmdline}
2113 Use @var{cmdline} as kernel command line
2116 DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
2117 "-initrd file use 'file
' as initial ram disk\n", QEMU_ARCH_ALL)
2119 @item -initrd @var{file}
2121 Use @var{file} as initial ram disk.
2123 @item -initrd "@var{file1} arg=foo,@var{file2}"
2125 This syntax is only available with multiboot.
2127 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
2131 DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
2132 "-dtb file use 'file
' as device tree image\n", QEMU_ARCH_ALL)
2134 @item -dtb @var{file}
2136 Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
2146 DEFHEADING(Debug/Expert options:)
2152 DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
2153 "-serial dev redirect the serial port to char device 'dev
'\n",
2156 @item -serial @var{dev}
2158 Redirect the virtual serial port to host character device
2159 @var{dev}. The default device is @code{vc} in graphical mode and
2160 @code{stdio} in non graphical mode.
2162 This option can be used several times to simulate up to 4 serial
2165 Use @code{-serial none} to disable all serial ports.
2167 Available character devices are:
2169 @item vc[:@var{W}x@var{H}]
2170 Virtual console. Optionally, a width and height can be given in pixel with
2174 It is also possible to specify width or height in characters:
2179 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
2181 No device is allocated.
2185 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
2186 parameters are set according to the emulated ones.
2187 @item /dev/parport@var{N}
2188 [Linux only, parallel port only] Use host parallel port
2189 @var{N}. Currently SPP and EPP parallel port features can be used.
2190 @item file:@var{filename}
2191 Write output to @var{filename}. No character can be read.
2193 [Unix only] standard input/output
2194 @item pipe:@var{filename}
2195 name pipe @var{filename}
2197 [Windows only] Use host serial port @var{n}
2198 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
2199 This implements UDP Net Console.
2200 When @var{remote_host} or @var{src_ip} are not specified
2201 they default to @code{0.0.0.0}.
2202 When not using a specified @var{src_port} a random port is automatically chosen.
2204 If you just want a simple readonly console you can use @code{netcat} or
2205 @code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
2206 @code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
2207 will appear in the netconsole session.
2209 If you plan to send characters back via netconsole or you want to stop
2210 and start QEMU a lot of times, you should have QEMU use the same
2211 source port each time by using something like @code{-serial
2212 udp::4555@@:4556} to QEMU. Another approach is to use a patched
2213 version of netcat which can listen to a TCP port and send and receive
2214 characters via udp. If you have a patched version of netcat which
2215 activates telnet remote echo and single char transfer, then you can
2216 use the following options to step up a netcat redirector to allow
2217 telnet on port 5555 to access the QEMU port.
2220 -serial udp::4555@@:4556
2221 @item netcat options:
2222 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
2223 @item telnet options:
2227 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay]
2228 The TCP Net Console has two modes of operation. It can send the serial
2229 I/O to a location or wait for a connection from a location. By default
2230 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
2231 the @var{server} option QEMU will wait for a client socket application
2232 to connect to the port before continuing, unless the @code{nowait}
2233 option was specified. The @code{nodelay} option disables the Nagle buffering
2234 algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only
2235 one TCP connection at a time is accepted. You can use @code{telnet} to
2236 connect to the corresponding character device.
2238 @item Example to send tcp console to 192.168.0.2 port 4444
2239 -serial tcp:192.168.0.2:4444
2240 @item Example to listen and wait on port 4444 for connection
2241 -serial tcp::4444,server
2242 @item Example to not wait and listen on ip 192.168.0.100 port 4444
2243 -serial tcp:192.168.0.100:4444,server,nowait
2246 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
2247 The telnet protocol is used instead of raw tcp sockets. The options
2248 work the same as if you had specified @code{-serial tcp}. The
2249 difference is that the port acts like a telnet server or client using
2250 telnet option negotiation. This will also allow you to send the
2251 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
2252 sequence. Typically in unix telnet you do it with Control-] and then
2253 type "send break" followed by pressing the enter key.
2255 @item unix:@var{path}[,server][,nowait]
2256 A unix domain socket is used instead of a tcp socket. The option works the
2257 same as if you had specified @code{-serial tcp} except the unix domain socket
2258 @var{path} is used for connections.
2260 @item mon:@var{dev_string}
2261 This is a special option to allow the monitor to be multiplexed onto
2262 another serial port. The monitor is accessed with key sequence of
2263 @key{Control-a} and then pressing @key{c}. See monitor access
2264 @ref{pcsys_keys} in the -nographic section for more keys.
2265 @var{dev_string} should be any one of the serial devices specified
2266 above. An example to multiplex the monitor onto a telnet server
2267 listening on port 4444 would be:
2269 @item -serial mon:telnet::4444,server,nowait
2273 Braille device. This will use BrlAPI to display the braille output on a real
2277 Three button serial mouse. Configure the guest to use Microsoft protocol.
2281 DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
2282 "-parallel dev redirect the parallel port to char device 'dev
'\n",
2285 @item -parallel @var{dev}
2287 Redirect the virtual parallel port to host device @var{dev} (same
2288 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
2289 be used to use hardware devices connected on the corresponding host
2292 This option can be used several times to simulate up to 3 parallel
2295 Use @code{-parallel none} to disable all parallel ports.
2298 DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
2299 "-monitor dev redirect the monitor to char device 'dev
'\n",
2302 @item -monitor @var{dev}
2304 Redirect the monitor to host device @var{dev} (same devices as the
2306 The default device is @code{vc} in graphical mode and @code{stdio} in
2309 DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
2310 "-qmp dev like -monitor but opens in 'control
' mode\n",
2313 @item -qmp @var{dev}
2315 Like -monitor but opens in 'control
' mode.
2318 DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
2319 "-mon chardev=[name][,mode=readline|control][,default]\n", QEMU_ARCH_ALL)
2321 @item -mon chardev=[name][,mode=readline|control][,default]
2323 Setup monitor on chardev @var{name}.
2326 DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
2327 "-debugcon dev redirect the debug console to char device 'dev
'\n",
2330 @item -debugcon @var{dev}
2332 Redirect the debug console to host device @var{dev} (same devices as the
2333 serial port). The debug console is an I/O port which is typically port
2334 0xe9; writing to that I/O port sends output to this device.
2335 The default device is @code{vc} in graphical mode and @code{stdio} in
2339 DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
2340 "-pidfile file write PID to 'file
'\n", QEMU_ARCH_ALL)
2342 @item -pidfile @var{file}
2344 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
2348 DEF("singlestep", 0, QEMU_OPTION_singlestep, \
2349 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL)
2353 Run the emulation in single step mode.
2356 DEF("S", 0, QEMU_OPTION_S, \
2357 "-S freeze CPU at startup (use 'c
' to start execution)\n",
2362 Do not start CPU at startup (you must type 'c
' in the monitor).
2365 DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
2366 "-gdb dev wait for gdb connection on 'dev
'\n", QEMU_ARCH_ALL)
2368 @item -gdb @var{dev}
2370 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
2371 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
2372 stdio are reasonable use case. The latter is allowing to start QEMU from
2373 within gdb and establish the connection via a pipe:
2375 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
2379 DEF("s", 0, QEMU_OPTION_s, \
2380 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
2385 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
2386 (@pxref{gdb_usage}).
2389 DEF("d", HAS_ARG, QEMU_OPTION_d, \
2390 "-d item1,... output log to /tmp/qemu.log (use -d ? for a list of log items)\n",
2395 Output log in /tmp/qemu.log
2398 DEF("D", HAS_ARG, QEMU_OPTION_D, \
2399 "-D logfile output log to logfile (instead of the default /tmp/qemu.log)\n",
2402 @item -D @var{logfile}
2404 Output log in @var{logfile} instead of /tmp/qemu.log
2407 DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
2408 "-hdachs c,h,s[,t]\n" \
2409 " force hard disk 0 physical geometry and the optional BIOS\n" \
2410 " translation (t=none or lba) (usually QEMU can guess them)\n",
2413 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
2415 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
2416 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
2417 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
2418 all those parameters. This option is useful for old MS-DOS disk
2422 DEF("L", HAS_ARG, QEMU_OPTION_L, \
2423 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
2428 Set the directory for the BIOS, VGA BIOS and keymaps.
2431 DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
2432 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL)
2434 @item -bios @var{file}
2436 Set the filename for the BIOS.
2439 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
2440 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL)
2444 Enable KVM full virtualization support. This option is only available
2445 if KVM support is enabled when compiling.
2448 DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
2449 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL)
2450 DEF("xen-create", 0, QEMU_OPTION_xen_create,
2451 "-xen-create create domain using xen hypercalls, bypassing xend\n"
2452 " warning: should not be used when xend is in use\n",
2454 DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
2455 "-xen-attach attach to existing xen domain\n"
2456 " xend will use this when starting QEMU\n",
2459 @item -xen-domid @var{id}
2461 Specify xen guest domain @var{id} (XEN only).
2464 Create domain using xen hypercalls, bypassing xend.
2465 Warning: should not be used when xend is in use (XEN only).
2468 Attach to existing xen domain.
2469 xend will use this when starting QEMU (XEN only).
2472 DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
2473 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL)
2477 Exit instead of rebooting.
2480 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
2481 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL)
2484 @findex -no-shutdown
2485 Don't exit QEMU on guest shutdown
, but instead only stop the emulation
.
2486 This allows
for instance switching to monitor to commit changes to the
2490 DEF("loadvm", HAS_ARG
, QEMU_OPTION_loadvm
, \
2491 "-loadvm [tag|id]\n" \
2492 " start right away with a saved state (loadvm in monitor)\n",
2495 @item
-loadvm @
var{file
}
2497 Start right away with a saved
state (@code
{loadvm
} in monitor
)
2501 DEF("daemonize", 0, QEMU_OPTION_daemonize
, \
2502 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL
)
2507 Daemonize the QEMU process after initialization
. QEMU will not detach from
2508 standard IO until it is ready to receive connections on any of its devices
.
2509 This option is a useful way
for external programs to launch QEMU without having
2510 to cope with initialization race conditions
.
2513 DEF("option-rom", HAS_ARG
, QEMU_OPTION_option_rom
, \
2514 "-option-rom rom load a file, rom, into the option ROM space\n",
2517 @item
-option
-rom @
var{file
}
2519 Load the contents of @
var{file
} as an option ROM
.
2520 This option is useful to load things like EtherBoot
.
2523 DEF("clock", HAS_ARG
, QEMU_OPTION_clock
, \
2524 "-clock force the use of the given methods for timer alarm.\n" \
2525 " To see what timers are available use -clock ?\n",
2528 @item
-clock @
var{method
}
2530 Force the use of the given methods
for timer alarm
. To see what timers
2531 are available use
-clock ?
.
2534 HXCOMM Options deprecated by
-rtc
2535 DEF("localtime", 0, QEMU_OPTION_localtime
, "", QEMU_ARCH_ALL
)
2536 DEF("startdate", HAS_ARG
, QEMU_OPTION_startdate
, "", QEMU_ARCH_ALL
)
2538 DEF("rtc", HAS_ARG
, QEMU_OPTION_rtc
, \
2539 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
2540 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
2545 @item
-rtc
[base
=utc|localtime|@
var{date
}][,clock
=host|vm
][,driftfix
=none|slew
]
2547 Specify @option
{base
} as @code
{utc
} or @code
{localtime
} to let the RTC start at the current
2548 UTC or local time
, respectively
. @code
{localtime
} is required
for correct date
in
2549 MS
-DOS or Windows
. To start at a specific point
in time
, provide @
var{date
} in the
2550 format @code
{2006-06-17T16
:01:21} or @code
{2006-06-17}. The
default base is UTC
.
2552 By
default the RTC is driven by the host system time
. This allows to use the
2553 RTC as accurate reference clock inside the guest
, specifically
if the host
2554 time is smoothly following an accurate external reference clock
, e
.g
. via NTP
.
2555 If you want to isolate the guest time from the host
, you can set @option
{clock
}
2556 to @code
{rt
} instead
. To even prevent it from progressing during suspension
,
2557 you can set it to @code
{vm
}.
2559 Enable @option
{driftfix
} (i386 targets only
) if you experience time drift problems
,
2560 specifically with Windows
' ACPI HAL. This option will try to figure out how
2561 many timer interrupts were not processed by the Windows guest and will
2565 DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
2566 "-icount [N|auto]\n" \
2567 " enable virtual instruction counter with 2^N clock ticks per\n" \
2568 " instruction\n", QEMU_ARCH_ALL)
2570 @item -icount [@var{N}|auto]
2572 Enable virtual instruction counter. The virtual cpu will execute one
2573 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
2574 then the virtual cpu speed will be automatically adjusted to keep virtual
2575 time within a few seconds of real time.
2577 Note that while this option can give deterministic behavior, it does not
2578 provide cycle accurate emulation. Modern CPUs contain superscalar out of
2579 order cores with complex cache hierarchies. The number of instructions
2580 executed often has little or no correlation with actual performance.
2583 DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
2584 "-watchdog i6300esb|ib700\n" \
2585 " enable virtual hardware watchdog [default=none]\n",
2588 @item -watchdog @var{model}
2590 Create a virtual hardware watchdog device. Once enabled (by a guest
2591 action), the watchdog must be periodically polled by an agent inside
2592 the guest or else the guest will be restarted.
2594 The @var{model} is the model of hardware watchdog to emulate. Choices
2595 for model are: @code{ib700} (iBASE 700) which is a very simple ISA
2596 watchdog with a single timer, or @code{i6300esb} (Intel 6300ESB I/O
2597 controller hub) which is a much more featureful PCI-based dual-timer
2598 watchdog. Choose a model for which your guest has drivers.
2600 Use @code{-watchdog ?} to list available hardware models. Only one
2601 watchdog can be enabled for a guest.
2604 DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
2605 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
2606 " action when watchdog fires [default=reset]\n",
2609 @item -watchdog-action @var{action}
2611 The @var{action} controls what QEMU will do when the watchdog timer
2614 @code{reset} (forcefully reset the guest).
2615 Other possible actions are:
2616 @code{shutdown} (attempt to gracefully shutdown the guest),
2617 @code{poweroff} (forcefully poweroff the guest),
2618 @code{pause} (pause the guest),
2619 @code{debug} (print a debug message and continue), or
2620 @code{none} (do nothing).
2622 Note that the @code{shutdown} action requires that the guest responds
2623 to ACPI signals, which it may not be able to do in the sort of
2624 situations where the watchdog would have expired, and thus
2625 @code{-watchdog-action shutdown} is not recommended for production use.
2630 @item -watchdog i6300esb -watchdog-action pause
2631 @item -watchdog ib700
2635 DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
2636 "-echr chr set terminal escape character instead of ctrl-a\n",
2640 @item -echr @var{numeric_ascii_value}
2642 Change the escape character used for switching to the monitor when using
2643 monitor and serial sharing. The default is @code{0x01} when using the
2644 @code{-nographic} option. @code{0x01} is equal to pressing
2645 @code{Control-a}. You can select a different character from the ascii
2646 control keys where 1 through 26 map to Control-a through Control-z. For
2647 instance you could use the either of the following to change the escape
2648 character to Control-t.
2655 DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
2656 "-virtioconsole c\n" \
2657 " set virtio console\n", QEMU_ARCH_ALL)
2659 @item -virtioconsole @var{c}
2660 @findex -virtioconsole
2663 This option is maintained for backward compatibility.
2665 Please use @code{-device virtconsole} for the new way of invocation.
2668 DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
2669 "-show-cursor show cursor\n", QEMU_ARCH_ALL)
2672 @findex -show-cursor
2676 DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
2677 "-tb-size n set TB size\n", QEMU_ARCH_ALL)
2679 @item -tb-size @var{n}
2684 DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
2685 "-incoming p prepare for incoming migration, listen on port p\n",
2688 @item -incoming @var{port}
2690 Prepare for incoming migration, listen on @var{port}.
2693 DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
2694 "-nodefaults don't create
default devices
\n", QEMU_ARCH_ALL)
2698 Don't create default devices. Normally, QEMU sets the default devices like serial
2699 port, parallel port, virtual console, monitor device, VGA adapter, floppy and
2700 CD-ROM drive and others. The @code{-nodefaults} option will disable all those
2705 DEF("chroot
", HAS_ARG, QEMU_OPTION_chroot, \
2706 "-chroot dir chroot to dir just before starting the VM
\n",
2710 @item -chroot @var{dir}
2712 Immediately before starting guest execution, chroot to the specified
2713 directory. Especially useful in combination with -runas.
2717 DEF("runas
", HAS_ARG, QEMU_OPTION_runas, \
2718 "-runas user change to user id user just before starting the VM
\n",
2722 @item -runas @var{user}
2724 Immediately before starting guest execution, drop root privileges, switching
2725 to the specified user.
2728 DEF("prom
-env
", HAS_ARG, QEMU_OPTION_prom_env,
2729 "-prom
-env variable
=value
\n"
2730 " set OpenBIOS nvram variables
\n",
2731 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
2733 @item -prom-env @var{variable}=@var{value}
2735 Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
2737 DEF("semihosting
", 0, QEMU_OPTION_semihosting,
2738 "-semihosting semihosting mode
\n", QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA)
2741 @findex -semihosting
2742 Semihosting mode (ARM, M68K, Xtensa only).
2744 DEF("old
-param
", 0, QEMU_OPTION_old_param,
2745 "-old
-param old param mode
\n", QEMU_ARCH_ARM)
2748 @findex -old-param (ARM)
2749 Old param mode (ARM only).
2752 DEF("sandbox
", HAS_ARG, QEMU_OPTION_sandbox, \
2753 "-sandbox
<arg
> Enable seccomp mode
2 system call
filter (default 'off').\n",
2758 Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
2759 disable it. The default is 'off'.
2762 DEF("readconfig
", HAS_ARG, QEMU_OPTION_readconfig,
2763 "-readconfig
<file
>\n", QEMU_ARCH_ALL)
2765 @item -readconfig @var{file}
2767 Read device configuration from @var{file}. This approach is useful when you want to spawn
2768 QEMU process with many command line options but you don't want to exceed the command line
2771 DEF("writeconfig
", HAS_ARG, QEMU_OPTION_writeconfig,
2772 "-writeconfig
<file
>\n"
2773 " read
/write config file
\n", QEMU_ARCH_ALL)
2775 @item -writeconfig @var{file}
2776 @findex -writeconfig
2777 Write device configuration to @var{file}. The @var{file} can be either filename to save
2778 command line and device configuration into file or dash @code{-}) character to print the
2779 output to stdout. This can be later used as input file for @code{-readconfig} option.
2781 DEF("nodefconfig
", 0, QEMU_OPTION_nodefconfig,
2783 " do not load
default config files at startup
\n",
2787 @findex -nodefconfig
2788 Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
2789 The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
2791 DEF("no
-user
-config
", 0, QEMU_OPTION_nouserconfig,
2793 " do not load user
-provided config files at startup
\n",
2796 @item -no-user-config
2797 @findex -no-user-config
2798 The @code{-no-user-config} option makes QEMU not load any of the user-provided
2799 config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config
2800 files from @var{datadir}.
2802 DEF("trace", HAS_ARG, QEMU_OPTION_trace,
2803 "-trace [events
=<file
>][,file
=<file
>]\n"
2804 " specify tracing options
\n",
2807 HXCOMM This line is not accurate, as some sub-options are backend-specific but
2808 HXCOMM HX does not support conditional compilation of text.
2809 @item -trace [events=@var{file}][,file=@var{file}]
2812 Specify tracing options.
2815 @item events=@var{file}
2816 Immediately enable events listed in @var{file}.
2817 The file must contain one event name (as listed in the @var{trace-events} file)
2819 This option is only available if QEMU has been compiled with
2820 either @var{simple} or @var{stderr} tracing backend.
2821 @item file=@var{file}
2822 Log output traces to @var{file}.
2824 This option is only available if QEMU has been compiled with
2825 the @var{simple} tracing backend.
2829 DEF("qtest
", HAS_ARG, QEMU_OPTION_qtest,
2830 "-qtest CHR specify tracing options
\n",
2833 DEF("qtest
-log
", HAS_ARG, QEMU_OPTION_qtest_log,
2834 "-qtest
-log LOG specify tracing options
\n",
2838 DEF("enable
-fips
", 0, QEMU_OPTION_enablefips,
2839 "-enable
-fips enable FIPS
140-2 compliance
\n",
2844 @findex -enable-fips
2845 Enable FIPS 140-2 compliance mode.
2848 HXCOMM This is the last statement. Insert new options before this line!