1 HXCOMM Use
DEFHEADING() to define headings
in both help text and texi
2 HXCOMM Text between STEXI and ETEXI are copied to texi version and
3 HXCOMM discarded from C version
4 HXCOMM
DEF(option
, HAS_ARG
/0, opt_enum
, opt_help
, arch_mask
) is used to
5 HXCOMM construct option structures
, enums and help message
for specified
7 HXCOMM HXCOMM can be used
for comments
, discarded from both texi and C
9 DEFHEADING(Standard options
:)
14 DEF("help", 0, QEMU_OPTION_h
,
15 "-h or -help display this help and exit\n", QEMU_ARCH_ALL
)
22 DEF("version", 0, QEMU_OPTION_version
,
23 "-version display version information and exit\n", QEMU_ARCH_ALL
)
27 Display version information and exit
30 DEF("machine", HAS_ARG
, QEMU_OPTION_machine
, \
31 "-machine [type=]name[,prop[=value][,...]]\n"
32 " selects emulated machine ('-machine help' for list)\n"
33 " property accel=accel1[:accel2[:...]] selects accelerator\n"
34 " supported accelerators are kvm, xen, tcg (default: tcg)\n"
35 " kernel_irqchip=on|off controls accelerated irqchip support\n"
36 " vmport=on|off|auto controls emulation of vmport (default: auto)\n"
37 " kvm_shadow_mem=size of KVM shadow MMU\n"
38 " dump-guest-core=on|off include guest memory in a core dump (default=on)\n"
39 " mem-merge=on|off controls memory merge support (default: on)\n"
40 " iommu=on|off controls emulated Intel IOMMU (VT-d) support (default=off)\n",
43 @item
-machine
[type
=]@
var{name
}[,prop
=@
var{value
}[,...]]
45 Select the emulated machine by @
var{name
}. Use @code
{-machine help
} to list
46 available machines
. Supported machine properties are
:
48 @item accel
=@
var{accels1
}[:@
var{accels2
}[:...]]
49 This is used to enable an accelerator
. Depending on the target architecture
,
50 kvm
, xen
, or tcg can be available
. By
default, tcg is used
. If there is more
51 than one accelerator specified
, the next one is used
if the previous one fails
53 @item kernel_irqchip
=on|off
54 Enables
in-kernel irqchip support
for the chosen accelerator when available
.
55 @item vmport
=on|off|auto
56 Enables emulation of VMWare IO port
, for vmmouse etc
. auto says to select the
57 value based on accel
. For accel
=xen the
default is off otherwise the
default
59 @item kvm_shadow_mem
=size
60 Defines the size of the KVM shadow MMU
.
61 @item dump
-guest
-core
=on|off
62 Include guest memory
in a core dump
. The
default is on
.
63 @item mem
-merge
=on|off
64 Enables or disables memory merge support
. This feature
, when supported by
65 the host
, de
-duplicates identical memory pages among VMs instances
68 Enables or disables emulated Intel
IOMMU (VT
-d
) support
. The
default is off
.
72 HXCOMM Deprecated by
-machine
73 DEF("M", HAS_ARG
, QEMU_OPTION_M
, "", QEMU_ARCH_ALL
)
75 DEF("cpu", HAS_ARG
, QEMU_OPTION_cpu
,
76 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL
)
78 @item
-cpu @
var{model
}
80 Select CPU
model (@code
{-cpu help
} for list and additional feature selection
)
83 DEF("smp", HAS_ARG
, QEMU_OPTION_smp
,
84 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
85 " set the number of CPUs to 'n' [default=1]\n"
86 " maxcpus= maximum number of total cpus, including\n"
87 " offline CPUs for hotplug, etc\n"
88 " cores= number of CPU cores on one socket\n"
89 " threads= number of threads on one CPU core\n"
90 " sockets= number of discrete sockets in the system\n",
93 @item
-smp
[cpus
=]@
var{n
}[,cores
=@
var{cores
}][,threads
=@
var{threads
}][,sockets
=@
var{sockets
}][,maxcpus
=@
var{maxcpus
}]
95 Simulate an SMP system with @
var{n
} CPUs
. On the PC target
, up to
255
96 CPUs are supported
. On Sparc32 target
, Linux limits the number of usable CPUs
98 For the PC target
, the number of @
var{cores
} per socket
, the number
99 of @
var{threads
} per cores and the total number of @
var{sockets
} can be
100 specified
. Missing values will be computed
. If any on the three values is
101 given
, the total number of CPUs @
var{n
} can be omitted
. @
var{maxcpus
}
102 specifies the maximum number of hotpluggable CPUs
.
105 DEF("numa", HAS_ARG
, QEMU_OPTION_numa
,
106 "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n"
107 "-numa node[,memdev=id][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL
)
109 @item
-numa node
[,mem
=@
var{size
}][,cpus
=@
var{cpu
[-cpu
]}][,nodeid
=@
var{node
}]
110 @item
-numa node
[,memdev
=@
var{id
}][,cpus
=@
var{cpu
[-cpu
]}][,nodeid
=@
var{node
}]
112 Simulate a multi node NUMA system
. If @samp
{mem
}, @samp
{memdev
}
113 and @samp
{cpus
} are omitted
, resources are split equally
. Also
, note
114 that the
-@option
{numa
} option doesn
't allocate any of the specified
115 resources. That is, it just assigns existing resources to NUMA nodes. This
116 means that one still has to use the @option{-m}, @option{-smp} options
117 to allocate RAM and VCPUs respectively, and possibly @option{-object}
118 to specify the memory backend for the @samp{memdev} suboption.
120 @samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, if one
121 node uses @samp{memdev}, all of them have to use it.
124 DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
125 "-add-fd fd=fd,set=set[,opaque=opaque]\n"
126 " Add 'fd
' to fd 'set
'\n", QEMU_ARCH_ALL)
128 @item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}]
131 Add a file descriptor to an fd set. Valid options are:
135 This option defines the file descriptor of which a duplicate is added to fd set.
136 The file descriptor cannot be stdin, stdout, or stderr.
138 This option defines the ID of the fd set to add the file descriptor to.
139 @item opaque=@var{opaque}
140 This option defines a free-form string that can be used to describe @var{fd}.
143 You can open an image using pre-opened file descriptors from an fd set:
146 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
147 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
148 -drive file=/dev/fdset/2,index=0,media=disk
152 DEF("set", HAS_ARG, QEMU_OPTION_set,
153 "-set group.id.arg=value\n"
154 " set <arg> parameter for item <id> of type <group>\n"
155 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL)
157 @item -set @var{group}.@var{id}.@var{arg}=@var{value}
159 Set parameter @var{arg} for item @var{id} of type @var{group}\n"
162 DEF("global", HAS_ARG, QEMU_OPTION_global,
163 "-global driver.prop=value\n"
164 " set a global default for a driver property\n",
167 @item -global @var{driver}.@var{prop}=@var{value}
169 Set default value of @var{driver}'s property @
var{prop
} to @
var{value
}, e
.g
.:
172 qemu
-system
-i386
-global ide
-drive
.physical_block_size
=4096 -drive file
=file
,if=ide
,index
=0,media
=disk
175 In particular
, you can use
this to set driver properties
for devices which are
176 created automatically by the machine model
. To create a device which is not
177 created automatically and set properties on it
, use
-@option
{device
}.
180 DEF("boot", HAS_ARG
, QEMU_OPTION_boot
,
181 "-boot [order=drives][,once=drives][,menu=on|off]\n"
182 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
183 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
184 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n"
185 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n"
186 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n",
189 @item
-boot
[order
=@
var{drives
}][,once
=@
var{drives
}][,menu
=on|off
][,splash
=@
var{sp_name
}][,splash
-time
=@
var{sp_time
}][,reboot
-timeout
=@
var{rb_timeout
}][,strict
=on|off
]
191 Specify boot order @
var{drives
} as a string of drive letters
. Valid
192 drive letters depend on the target achitecture
. The x86 PC uses
: a
, b
193 (floppy
1 and
2), c (first hard disk
), d (first CD
-ROM
), n
-p (Etherboot
194 from network adapter
1-4), hard disk boot is the
default. To apply a
195 particular boot order only on the first startup
, specify it via
198 Interactive boot menus
/prompts can be enabled via @option
{menu
=on
} as far
199 as firmware
/BIOS supports them
. The
default is non
-interactive boot
.
201 A splash picture could be passed to bios
, enabling user to show it as logo
,
202 when option splash
=@
var{sp_name
} is given and menu
=on
, If firmware
/BIOS
203 supports them
. Currently Seabios
for X86 system support it
.
204 limitation
: The splash file could be a jpeg file or a BMP file
in 24 BPP
205 format(true color
). The resolution should be supported by the SVGA mode
, so
206 the recommended is
320x240
, 640x480
, 800x640
.
208 A timeout could be passed to bios
, guest will pause
for @
var{rb_timeout
} ms
209 when boot failed
, then reboot
. If @
var{rb_timeout
} is
'-1', guest will not
210 reboot
, qemu passes
'-1' to bios by
default. Currently Seabios
for X86
213 Do strict boot via @option
{strict
=on
} as far as firmware
/BIOS
214 supports it
. This only effects when boot priority is changed by
215 bootindex options
. The
default is non
-strict boot
.
218 #
try to boot from network first
, then from hard disk
219 qemu
-system
-i386
-boot order
=nc
220 # boot from CD
-ROM first
, switch back to
default order after reboot
221 qemu
-system
-i386
-boot once
=d
222 # boot with a splash picture
for 5 seconds
.
223 qemu
-system
-i386
-boot menu
=on
,splash
=/root
/boot
.bmp
,splash
-time
=5000
226 Note
: The legacy format
'-boot @var{drives}' is still supported but its
227 use is discouraged as it may be removed from future versions
.
230 DEF("m", HAS_ARG
, QEMU_OPTION_m
,
231 "-m[emory] [size=]megs[,slots=n,maxmem=size]\n"
232 " configure guest RAM\n"
233 " size: initial amount of guest memory (default: "
234 stringify(DEFAULT_RAM_SIZE
) "MiB)\n"
235 " slots: number of hotplug slots (default: none)\n"
236 " maxmem: maximum amount of guest memory (default: none)\n"
237 "NOTE: Some architectures might enforce a specific granularity\n",
240 @item
-m
[size
=]@
var{megs
}
242 Set virtual RAM size to @
var{megs
} megabytes
. Default is
128 MiB
. Optionally
,
243 a suffix of ``M
'' or ``G
'' can be used to signify a value
in megabytes or
244 gigabytes respectively
. Optional pair @
var{slots
}, @
var{maxmem
} could be used
245 to set amount of hotluggable memory slots and possible maximum amount of memory
.
248 DEF("mem-path", HAS_ARG
, QEMU_OPTION_mempath
,
249 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL
)
251 @item
-mem
-path @
var{path
}
253 Allocate guest RAM from a temporarily created file
in @
var{path
}.
256 DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc
,
257 "-mem-prealloc preallocate guest memory (use with -mem-path)\n",
261 @findex
-mem
-prealloc
262 Preallocate memory when
using -mem
-path
.
265 DEF("k", HAS_ARG
, QEMU_OPTION_k
,
266 "-k language use keyboard layout (for example 'fr' for French)\n",
269 @item
-k @
var{language
}
271 Use keyboard layout @
var{language
} (for example @code
{fr
} for
272 French
). This option is only needed where it is not easy to get raw PC
273 keycodes (e
.g
. on Macs
, with some X11 servers or with a VNC
274 display
). You don
't normally need to use it on PC/Linux or PC/Windows
277 The available layouts are:
279 ar de-ch es fo fr-ca hu ja mk no pt-br sv
280 da en-gb et fr fr-ch is lt nl pl ru th
281 de en-us fi fr-be hr it lv nl-be pt sl tr
284 The default is @code{en-us}.
288 DEF("audio-help", 0, QEMU_OPTION_audio_help,
289 "-audio-help print list of audio drivers and their options\n",
294 Will show the audio subsystem help: list of drivers, tunable
298 DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
299 "-soundhw c1,... enable audio support\n"
300 " and only specified sound cards (comma separated list)\n"
301 " use '-soundhw help
' to get the list of supported cards\n"
302 " use '-soundhw all
' to enable all of them\n", QEMU_ARCH_ALL)
304 @item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
306 Enable audio and selected sound hardware. Use 'help
' to print all
307 available sound hardware.
310 qemu-system-i386 -soundhw sb16,adlib disk.img
311 qemu-system-i386 -soundhw es1370 disk.img
312 qemu-system-i386 -soundhw ac97 disk.img
313 qemu-system-i386 -soundhw hda disk.img
314 qemu-system-i386 -soundhw all disk.img
315 qemu-system-i386 -soundhw help
318 Note that Linux's i810_audio OSS
kernel (for AC97
) module might
319 require manually specifying clocking
.
322 modprobe i810_audio clocking
=48000
326 DEF("balloon", HAS_ARG
, QEMU_OPTION_balloon
,
327 "-balloon none disable balloon device\n"
328 "-balloon virtio[,addr=str]\n"
329 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL
)
333 Disable balloon device
.
334 @item
-balloon virtio
[,addr
=@
var{addr
}]
335 Enable virtio balloon
device (default), optionally with PCI address
339 DEF("device", HAS_ARG
, QEMU_OPTION_device
,
340 "-device driver[,prop[=value][,...]]\n"
341 " add device (based on driver)\n"
342 " prop=value,... sets driver properties\n"
343 " use '-device help' to print all possible drivers\n"
344 " use '-device driver,help' to print all possible properties\n",
347 @item
-device @
var{driver
}[,@
var{prop
}[=@
var{value
}][,...]]
349 Add device @
var{driver
}. @
var{prop
}=@
var{value
} sets driver
350 properties
. Valid properties depend on the driver
. To get help on
351 possible drivers and properties
, use @code
{-device help
} and
352 @code
{-device @
var{driver
},help
}.
355 DEF("name", HAS_ARG
, QEMU_OPTION_name
,
356 "-name string1[,process=string2][,debug-threads=on|off]\n"
357 " set the name of the guest\n"
358 " string1 sets the window title and string2 the process name (on Linux)\n"
359 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n"
360 " NOTE: The thread names are for debugging and not a stable API.\n",
363 @item
-name @
var{name
}
365 Sets the @
var{name
} of the guest
.
366 This name will be displayed
in the SDL window caption
.
367 The @
var{name
} will also be used
for the VNC server
.
368 Also optionally set the top visible process name
in Linux
.
369 Naming of individual threads can also be enabled on Linux to aid debugging
.
372 DEF("uuid", HAS_ARG
, QEMU_OPTION_uuid
,
373 "-uuid %08x-%04x-%04x-%04x-%012x\n"
374 " specify machine UUID\n", QEMU_ARCH_ALL
)
376 @item
-uuid @
var{uuid
}
386 DEFHEADING(Block device options
:)
391 DEF("fda", HAS_ARG
, QEMU_OPTION_fda
,
392 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL
)
393 DEF("fdb", HAS_ARG
, QEMU_OPTION_fdb
, "", QEMU_ARCH_ALL
)
395 @item
-fda @
var{file
}
396 @item
-fdb @
var{file
}
399 Use @
var{file
} as floppy disk
0/1 image (@pxref
{disk_images
}). You can
400 use the host floppy by
using @file
{/dev
/fd0
} as
filename (@pxref
{host_drives
}).
403 DEF("hda", HAS_ARG
, QEMU_OPTION_hda
,
404 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL
)
405 DEF("hdb", HAS_ARG
, QEMU_OPTION_hdb
, "", QEMU_ARCH_ALL
)
406 DEF("hdc", HAS_ARG
, QEMU_OPTION_hdc
,
407 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL
)
408 DEF("hdd", HAS_ARG
, QEMU_OPTION_hdd
, "", QEMU_ARCH_ALL
)
410 @item
-hda @
var{file
}
411 @item
-hdb @
var{file
}
412 @item
-hdc @
var{file
}
413 @item
-hdd @
var{file
}
418 Use @
var{file
} as hard disk
0, 1, 2 or
3 image (@pxref
{disk_images
}).
421 DEF("cdrom", HAS_ARG
, QEMU_OPTION_cdrom
,
422 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
425 @item
-cdrom @
var{file
}
427 Use @
var{file
} as CD
-ROM
image (you cannot use @option
{-hdc
} and
428 @option
{-cdrom
} at the same time
). You can use the host CD
-ROM by
429 using @file
{/dev
/cdrom
} as
filename (@pxref
{host_drives
}).
432 DEF("drive", HAS_ARG
, QEMU_OPTION_drive
,
433 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
434 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
435 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
436 " [,serial=s][,addr=A][,rerror=ignore|stop|report]\n"
437 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n"
438 " [,readonly=on|off][,copy-on-read=on|off]\n"
439 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n"
440 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n"
441 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n"
442 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n"
443 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n"
444 " [[,iops_size=is]]\n"
445 " use 'file' as a drive image\n", QEMU_ARCH_ALL
)
447 @item
-drive @
var{option
}[,@
var{option
}[,@
var{option
}[,...]]]
450 Define a
new drive
. Valid options are
:
453 @item file
=@
var{file
}
454 This option defines which disk
image (@pxref
{disk_images
}) to use with
455 this drive
. If the filename contains comma
, you must double it
456 (for instance
, "file=my,,file" to use file
"my,file").
458 Special files such as iSCSI devices can be specified
using protocol
459 specific URLs
. See the section
for "Device URL Syntax" for more information
.
460 @item
if=@
var{interface}
461 This option defines on which type on
interface the drive is connected
.
462 Available types are
: ide
, scsi
, sd
, mtd
, floppy
, pflash
, virtio
.
463 @item bus
=@
var{bus
},unit
=@
var{unit
}
464 These options define where is connected the drive by defining the bus number and
466 @item index
=@
var{index
}
467 This option defines where is connected the drive by
using an index
in the list
468 of available connectors of a given
interface type
.
469 @item media
=@
var{media
}
470 This option defines the type of the media
: disk or cdrom
.
471 @item cyls
=@
var{c
},heads
=@
var{h
},secs
=@
var{s
}[,trans
=@
var{t
}]
472 These options have the same definition as they have
in @option
{-hdachs
}.
473 @item snapshot
=@
var{snapshot
}
474 @
var{snapshot
} is
"on" or
"off" and controls snapshot mode
for the given drive
475 (see @option
{-snapshot
}).
476 @item cache
=@
var{cache
}
477 @
var{cache
} is
"none", "writeback", "unsafe", "directsync" or
"writethrough" and controls how the host cache is used to access block data
.
479 @
var{aio
} is
"threads", or
"native" and selects between pthread based disk I
/O and native Linux AIO
.
480 @item discard
=@
var{discard
}
481 @
var{discard
} is one of
"ignore" (or
"off") or
"unmap" (or
"on") and controls whether @dfn
{discard
} (also known as @dfn
{trim
} or @dfn
{unmap
}) requests are ignored or passed to the filesystem
. Some machine types may not support discard requests
.
482 @item format
=@
var{format
}
483 Specify which disk @
var{format
} will be used rather than detecting
484 the format
. Can be used to specifiy format
=raw to avoid interpreting
485 an untrusted format header
.
486 @item serial
=@
var{serial
}
487 This option specifies the serial number to assign to the device
.
488 @item addr
=@
var{addr
}
489 Specify the controller
's PCI address (if=virtio only).
490 @item werror=@var{action},rerror=@var{action}
491 Specify which @var{action} to take on write and read errors. Valid actions are:
492 "ignore" (ignore the error and try to continue), "stop" (pause QEMU),
493 "report" (report the error to the guest), "enospc" (pause QEMU only if the
494 host disk is full; report the error to the guest otherwise).
495 The default setting is @option{werror=enospc} and @option{rerror=report}.
497 Open drive @option{file} as read-only. Guest write attempts will fail.
498 @item copy-on-read=@var{copy-on-read}
499 @var{copy-on-read} is "on" or "off" and enables whether to copy read backing
500 file sectors into the image file.
501 @item detect-zeroes=@var{detect-zeroes}
502 @var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic
503 conversion of plain zero writes by the OS to driver specific optimized
504 zero write commands. You may even choose "unmap" if @var{discard} is set
505 to "unmap" to allow a zero write to be converted to an UNMAP operation.
508 By default, the @option{cache=writeback} mode is used. It will report data
509 writes as completed as soon as the data is present in the host page cache.
510 This is safe as long as your guest OS makes sure to correctly flush disk caches
511 where needed. If your guest OS does not handle volatile disk write caches
512 correctly and your host crashes or loses power, then the guest may experience
515 For such guests, you should consider using @option{cache=writethrough}. This
516 means that the host page cache will be used to read and write data, but write
517 notification will be sent to the guest only after QEMU has made sure to flush
518 each write to the disk. Be aware that this has a major impact on performance.
520 The host page cache can be avoided entirely with @option{cache=none}. This will
521 attempt to do disk IO directly to the guest's memory
. QEMU may still perform
522 an internal copy of the data
. Note that
this is considered a writeback mode and
523 the guest OS must handle the disk write cache correctly
in order to avoid data
524 corruption on host crashes
.
526 The host page cache can be avoided
while only sending write notifications to
527 the guest when the data has been flushed to the disk
using
528 @option
{cache
=directsync
}.
530 In
case you don
't care about data integrity over host failures, use
531 @option{cache=unsafe}. This option tells QEMU that it never needs to write any
532 data to the disk but can instead keep things in cache. If anything goes wrong,
533 like your host losing power, the disk storage getting disconnected accidentally,
534 etc. your image will most probably be rendered unusable. When using
535 the @option{-snapshot} option, unsafe caching is always used.
537 Copy-on-read avoids accessing the same backing file sectors repeatedly and is
538 useful when the backing file is over a slow network. By default copy-on-read
541 Instead of @option{-cdrom} you can use:
543 qemu-system-i386 -drive file=file,index=2,media=cdrom
546 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
549 qemu-system-i386 -drive file=file,index=0,media=disk
550 qemu-system-i386 -drive file=file,index=1,media=disk
551 qemu-system-i386 -drive file=file,index=2,media=disk
552 qemu-system-i386 -drive file=file,index=3,media=disk
555 You can open an image using pre-opened file descriptors from an fd set:
558 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
559 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
560 -drive file=/dev/fdset/2,index=0,media=disk
563 You can connect a CDROM to the slave of ide0:
565 qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
568 If you don't specify the
"file=" argument
, you define an empty drive
:
570 qemu
-system
-i386
-drive
if=ide
,index
=1,media
=cdrom
573 You can connect a SCSI disk with unit ID
6 on the bus #
0:
575 qemu
-system
-i386
-drive file
=file
,if=scsi
,bus
=0,unit
=6
578 Instead of @option
{-fda
}, @option
{-fdb
}, you can use
:
580 qemu
-system
-i386
-drive file
=file
,index
=0,if=floppy
581 qemu
-system
-i386
-drive file
=file
,index
=1,if=floppy
584 By
default, @
var{interface} is
"ide" and @
var{index
} is automatically
587 qemu
-system
-i386
-drive file
=a
-drive file
=b
"
591 qemu-system-i386 -hda a -hdb b
595 DEF("mtdblock
", HAS_ARG, QEMU_OPTION_mtdblock,
596 "-mtdblock file use
'file' as on
-board Flash memory image
\n",
599 @item -mtdblock @var{file}
601 Use @var{file} as on-board Flash memory image.
604 DEF("sd
", HAS_ARG, QEMU_OPTION_sd,
605 "-sd file use
'file' as SecureDigital card image
\n", QEMU_ARCH_ALL)
609 Use @var{file} as SecureDigital card image.
612 DEF("pflash
", HAS_ARG, QEMU_OPTION_pflash,
613 "-pflash file use
'file' as a parallel flash image
\n", QEMU_ARCH_ALL)
615 @item -pflash @var{file}
617 Use @var{file} as a parallel flash image.
620 DEF("snapshot
", 0, QEMU_OPTION_snapshot,
621 "-snapshot write to temporary files instead of disk image files
\n",
626 Write to temporary files instead of disk image files. In this case,
627 the raw disk image you use is not written back. You can however force
628 the write back by pressing @key{C-a s} (@pxref{disk_images}).
631 DEF("hdachs
", HAS_ARG, QEMU_OPTION_hdachs, \
632 "-hdachs c
,h
,s
[,t
]\n" \
633 " force hard disk
0 physical geometry and the optional BIOS
\n" \
634 " translation (t
=none or lba
) (usually QEMU can guess them
)\n",
637 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
639 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
640 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
641 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
642 all those parameters. This option is useful for old MS-DOS disk
646 DEF("fsdev
", HAS_ARG, QEMU_OPTION_fsdev,
647 "-fsdev fsdriver
,id
=id
[,path
=path
,][security_model
={mapped
-xattr|mapped
-file|passthrough|none
}]\n"
648 " [,writeout
=immediate
][,readonly
][,socket
=socket|sock_fd
=sock_fd
]\n",
653 @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}]
655 Define a new file system device. Valid options are:
658 This option specifies the fs driver backend to use.
659 Currently "local
", "handle
" and "proxy
" file system drivers are supported.
661 Specifies identifier for this device
662 @item path=@var{path}
663 Specifies the export path for the file system device. Files under
664 this path will be available to the 9p client on the guest.
665 @item security_model=@var{security_model}
666 Specifies the security model to be used for this export path.
667 Supported security models are "passthrough
", "mapped
-xattr
", "mapped
-file
" and "none
".
668 In "passthrough
" security model, files are stored using the same
669 credentials as they are created on the guest. This requires QEMU
670 to run as root. In "mapped
-xattr
" security model, some of the file
671 attributes like uid, gid, mode bits and link target are stored as
672 file attributes. For "mapped
-file
" these attributes are stored in the
673 hidden .virtfs_metadata directory. Directories exported by this security model cannot
674 interact with other unix tools. "none
" security model is same as
675 passthrough except the sever won't report failures if it fails to
676 set file attributes like ownership. Security model is mandatory
677 only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
678 security model as a parameter.
679 @item writeout=@var{writeout}
680 This is an optional argument. The only supported value is "immediate
".
681 This means that host page cache will be used to read and write data but
682 write notification will be sent to the guest only when the data has been
683 reported as written by the storage subsystem.
685 Enables exporting 9p share as a readonly mount for guests. By default
686 read-write access is given.
687 @item socket=@var{socket}
688 Enables proxy filesystem driver to use passed socket file for communicating
689 with virtfs-proxy-helper
690 @item sock_fd=@var{sock_fd}
691 Enables proxy filesystem driver to use passed socket descriptor for
692 communicating with virtfs-proxy-helper. Usually a helper like libvirt
693 will create socketpair and pass one of the fds as sock_fd
696 -fsdev option is used along with -device driver "virtio
-9p
-pci
".
697 @item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
698 Options for virtio-9p-pci driver are:
701 Specifies the id value specified along with -fsdev option
702 @item mount_tag=@var{mount_tag}
703 Specifies the tag name to be used by the guest to mount this export point
708 DEF("virtfs
", HAS_ARG, QEMU_OPTION_virtfs,
709 "-virtfs local
,path
=path
,mount_tag
=tag
,security_model
=[mapped
-xattr|mapped
-file|passthrough|none
]\n"
710 " [,writeout
=immediate
][,readonly
][,socket
=socket|sock_fd
=sock_fd
]\n",
715 @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}]
718 The general form of a Virtual File system pass-through options are:
721 This option specifies the fs driver backend to use.
722 Currently "local
", "handle
" and "proxy
" file system drivers are supported.
724 Specifies identifier for this device
725 @item path=@var{path}
726 Specifies the export path for the file system device. Files under
727 this path will be available to the 9p client on the guest.
728 @item security_model=@var{security_model}
729 Specifies the security model to be used for this export path.
730 Supported security models are "passthrough
", "mapped
-xattr
", "mapped
-file
" and "none
".
731 In "passthrough
" security model, files are stored using the same
732 credentials as they are created on the guest. This requires QEMU
733 to run as root. In "mapped
-xattr
" security model, some of the file
734 attributes like uid, gid, mode bits and link target are stored as
735 file attributes. For "mapped
-file
" these attributes are stored in the
736 hidden .virtfs_metadata directory. Directories exported by this security model cannot
737 interact with other unix tools. "none
" security model is same as
738 passthrough except the sever won't report failures if it fails to
739 set file attributes like ownership. Security model is mandatory only
740 for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
741 model as a parameter.
742 @item writeout=@var{writeout}
743 This is an optional argument. The only supported value is "immediate
".
744 This means that host page cache will be used to read and write data but
745 write notification will be sent to the guest only when the data has been
746 reported as written by the storage subsystem.
748 Enables exporting 9p share as a readonly mount for guests. By default
749 read-write access is given.
750 @item socket=@var{socket}
751 Enables proxy filesystem driver to use passed socket file for
752 communicating with virtfs-proxy-helper. Usually a helper like libvirt
753 will create socketpair and pass one of the fds as sock_fd
755 Enables proxy filesystem driver to use passed 'sock_fd' as the socket
756 descriptor for interfacing with virtfs-proxy-helper
760 DEF("virtfs_synth
", 0, QEMU_OPTION_virtfs_synth,
761 "-virtfs_synth Create synthetic file system image
\n",
765 @findex -virtfs_synth
766 Create synthetic file system image
774 DEFHEADING(USB options:)
779 DEF("usb
", 0, QEMU_OPTION_usb,
780 "-usb enable the USB
driver (will be the
default soon
)\n",
785 Enable the USB driver (will be the default soon)
788 DEF("usbdevice
", HAS_ARG, QEMU_OPTION_usbdevice,
789 "-usbdevice name add the host or guest USB device
'name'\n",
793 @item -usbdevice @var{devname}
795 Add the USB device @var{devname}. @xref{usb_devices}.
800 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
803 Pointer device that uses absolute coordinates (like a touchscreen). This
804 means QEMU is able to report the mouse position without having to grab the
805 mouse. Also overrides the PS/2 mouse emulation when activated.
807 @item disk:[format=@var{format}]:@var{file}
808 Mass storage device based on file. The optional @var{format} argument
809 will be used rather than detecting the format. Can be used to specifiy
810 @code{format=raw} to avoid interpreting an untrusted format header.
812 @item host:@var{bus}.@var{addr}
813 Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
815 @item host:@var{vendor_id}:@var{product_id}
816 Pass through the host device identified by @var{vendor_id}:@var{product_id}
819 @item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
820 Serial converter to host character device @var{dev}, see @code{-serial} for the
824 Braille device. This will use BrlAPI to display the braille output on a real
827 @item net:@var{options}
828 Network adapter that supports CDC ethernet and RNDIS protocols.
838 DEFHEADING(Display options:)
843 DEF("display
", HAS_ARG, QEMU_OPTION_display,
844 "-display sdl
[,frame
=on|off
][,alt_grab
=on|off
][,ctrl_grab
=on|off
]\n"
845 " [,window_close
=on|off
]|curses|none|
\n"
846 " gtk
[,grab_on_hover
=on|off
]|
\n"
847 " vnc
=<display
>[,<optargs
>]\n"
848 " select display type
\n", QEMU_ARCH_ALL)
850 @item -display @var{type}
852 Select type of display to use. This option is a replacement for the
853 old style -sdl/-curses/... options. Valid values for @var{type} are
856 Display video output via SDL (usually in a separate graphics
857 window; see the SDL documentation for other possibilities).
859 Display video output via curses. For graphics device models which
860 support a text mode, QEMU can display this output using a
861 curses/ncurses interface. Nothing is displayed when the graphics
862 device is in graphical mode or if the graphics device does not support
863 a text mode. Generally only the VGA device models support text mode.
865 Do not display video output. The guest will still see an emulated
866 graphics card, but its output will not be displayed to the QEMU
867 user. This option differs from the -nographic option in that it
868 only affects what is done with video output; -nographic also changes
869 the destination of the serial and parallel port data.
871 Display video output in a GTK window. This interface provides drop-down
872 menus and other UI elements to configure and control the VM during
875 Start a VNC server on display <arg>
879 DEF("nographic
", 0, QEMU_OPTION_nographic,
880 "-nographic disable graphical output and redirect serial I
/Os to console
\n",
885 Normally, QEMU uses SDL to display the VGA output. With this option,
886 you can totally disable graphical output so that QEMU is a simple
887 command line application. The emulated serial port is redirected on
888 the console and muxed with the monitor (unless redirected elsewhere
889 explicitly). Therefore, you can still use QEMU to debug a Linux kernel
890 with a serial console. Use @key{C-a h} for help on switching between
891 the console and monitor.
894 DEF("curses
", 0, QEMU_OPTION_curses,
895 "-curses use a curses
/ncurses
interface instead of SDL
\n",
900 Normally, QEMU uses SDL to display the VGA output. With this option,
901 QEMU can display the VGA output when in text mode using a
902 curses/ncurses interface. Nothing is displayed in graphical mode.
905 DEF("no
-frame
", 0, QEMU_OPTION_no_frame,
906 "-no
-frame open SDL window without a frame and window decorations
\n",
911 Do not use decorations for SDL windows and start them using the whole
912 available screen space. This makes the using QEMU in a dedicated desktop
913 workspace more convenient.
916 DEF("alt
-grab
", 0, QEMU_OPTION_alt_grab,
917 "-alt
-grab use Ctrl
-Alt
-Shift to grab
mouse (instead of Ctrl
-Alt
)\n",
922 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
923 affects the special keys (for fullscreen, monitor-mode switching, etc).
926 DEF("ctrl
-grab
", 0, QEMU_OPTION_ctrl_grab,
927 "-ctrl
-grab use Right
-Ctrl to grab
mouse (instead of Ctrl
-Alt
)\n",
932 Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
933 affects the special keys (for fullscreen, monitor-mode switching, etc).
936 DEF("no
-quit
", 0, QEMU_OPTION_no_quit,
937 "-no
-quit disable SDL window close capability
\n", QEMU_ARCH_ALL)
941 Disable SDL window close capability.
944 DEF("sdl
", 0, QEMU_OPTION_sdl,
945 "-sdl enable SDL
\n", QEMU_ARCH_ALL)
952 DEF("spice
", HAS_ARG, QEMU_OPTION_spice,
953 "-spice
[port
=port
][,tls
-port
=secured
-port
][,x509
-dir
=<dir
>]\n"
954 " [,x509
-key
-file
=<file
>][,x509
-key
-password
=<file
>]\n"
955 " [,x509
-cert
-file
=<file
>][,x509
-cacert
-file
=<file
>]\n"
956 " [,x509
-dh
-key
-file
=<file
>][,addr
=addr
][,ipv4|ipv6
]\n"
957 " [,tls
-ciphers
=<list
>]\n"
958 " [,tls
-channel
=[main|display|cursor|inputs|record|playback
]]\n"
959 " [,plaintext
-channel
=[main|display|cursor|inputs|record|playback
]]\n"
960 " [,sasl
][,password
=<secret
>][,disable
-ticketing
]\n"
961 " [,image
-compression
=[auto_glz|auto_lz|quic|glz|lz|off
]]\n"
962 " [,jpeg
-wan
-compression
=[auto|
never|always
]]\n"
963 " [,zlib
-glz
-wan
-compression
=[auto|
never|always
]]\n"
964 " [,streaming
-video
=[off|all|filter
]][,disable
-copy
-paste
]\n"
965 " [,disable
-agent
-file
-xfer
][,agent
-mouse
=[on|off
]]\n"
966 " [,playback
-compression
=[on|off
]][,seamless
-migration
=[on|off
]]\n"
968 " at least one of
{port
, tls
-port
} is mandatory
\n",
971 @item -spice @var{option}[,@var{option}[,...]]
973 Enable the spice remote desktop protocol. Valid options are
978 Set the TCP port spice is listening on for plaintext channels.
981 Set the IP address spice is listening on. Default is any address.
985 Force using the specified IP version.
987 @item password=<secret>
988 Set the password you need to authenticate.
991 Require that the client use SASL to authenticate with the spice.
992 The exact choice of authentication method used is controlled from the
993 system / user's SASL configuration file for the 'qemu' service. This
994 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
995 unprivileged user, an environment variable SASL_CONF_PATH can be used
996 to make it search alternate locations for the service config.
997 While some SASL auth methods can also provide data encryption (eg GSSAPI),
998 it is recommended that SASL always be combined with the 'tls' and
999 'x509' settings to enable use of SSL and server certificates. This
1000 ensures a data encryption preventing compromise of authentication
1003 @item disable-ticketing
1004 Allow client connects without authentication.
1006 @item disable-copy-paste
1007 Disable copy paste between the client and the guest.
1009 @item disable-agent-file-xfer
1010 Disable spice-vdagent based file-xfer between the client and the guest.
1013 Set the TCP port spice is listening on for encrypted channels.
1015 @item x509-dir=<dir>
1016 Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1018 @item x509-key-file=<file>
1019 @item x509-key-password=<file>
1020 @item x509-cert-file=<file>
1021 @item x509-cacert-file=<file>
1022 @item x509-dh-key-file=<file>
1023 The x509 file names can also be configured individually.
1025 @item tls-ciphers=<list>
1026 Specify which ciphers to use.
1028 @item tls-channel=[main|display|cursor|inputs|record|playback]
1029 @item plaintext-channel=[main|display|cursor|inputs|record|playback]
1030 Force specific channel to be used with or without TLS encryption. The
1031 options can be specified multiple times to configure multiple
1032 channels. The special name "default" can be used to set the default
1033 mode. For channels which are not explicitly forced into one mode the
1034 spice client is allowed to pick tls/plaintext as he pleases.
1036 @item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1037 Configure image compression (lossless).
1038 Default is auto_glz.
1040 @item jpeg-wan-compression=[auto|never|always]
1041 @item zlib-glz-wan-compression=[auto|never|always]
1042 Configure wan image compression (lossy for slow links).
1045 @item streaming-video=[off|all|filter]
1046 Configure video stream detection. Default is filter.
1048 @item agent-mouse=[on|off]
1049 Enable/disable passing mouse events via vdagent. Default is on.
1051 @item playback-compression=[on|off]
1052 Enable/disable audio stream compression (using celt 0.5.1). Default is on.
1054 @item seamless-migration=[on|off]
1055 Enable/disable spice seamless migration. Default is off.
1060 DEF("portrait
", 0, QEMU_OPTION_portrait,
1061 "-portrait rotate graphical output
90 deg
left (only PXA LCD
)\n",
1066 Rotate graphical output 90 deg left (only PXA LCD).
1069 DEF("rotate
", HAS_ARG, QEMU_OPTION_rotate,
1070 "-rotate
<deg
> rotate graphical output some deg
left (only PXA LCD
)\n",
1073 @item -rotate @var{deg}
1075 Rotate graphical output some deg left (only PXA LCD).
1078 DEF("vga
", HAS_ARG, QEMU_OPTION_vga,
1079 "-vga
[std|cirrus|vmware|qxl|xenfb|tcx|cg3|none
]\n"
1080 " select video card type
\n", QEMU_ARCH_ALL)
1082 @item -vga @var{type}
1084 Select type of VGA card to emulate. Valid values for @var{type} are
1087 Cirrus Logic GD5446 Video card. All Windows versions starting from
1088 Windows 95 should recognize and use this graphic card. For optimal
1089 performances, use 16 bit color depth in the guest and the host OS.
1090 (This one is the default)
1092 Standard VGA card with Bochs VBE extensions. If your guest OS
1093 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1094 to use high resolution modes (>= 1280x1024x16) then you should use
1097 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1098 recent XFree86/XOrg server or Windows guest with a driver for this
1101 QXL paravirtual graphic card. It is VGA compatible (including VESA
1102 2.0 VBE support). Works best with qxl guest drivers installed though.
1103 Recommended choice when using the spice protocol.
1105 (sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1106 sun4m machines and offers both 8-bit and 24-bit colour depths at a
1107 fixed resolution of 1024x768.
1109 (sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1110 for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1111 resolutions aimed at people wishing to run older Solaris versions.
1117 DEF("full
-screen
", 0, QEMU_OPTION_full_screen,
1118 "-full
-screen start
in full screen
\n", QEMU_ARCH_ALL)
1121 @findex -full-screen
1122 Start in full screen.
1125 DEF("g
", 1, QEMU_OPTION_g ,
1126 "-g WxH
[xDEPTH
] Set the initial graphical resolution and depth
\n",
1127 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1129 @item -g @var{width}x@var{height}[x@var{depth}]
1131 Set the initial graphical resolution and depth (PPC, SPARC only).
1134 DEF("vnc
", HAS_ARG, QEMU_OPTION_vnc ,
1135 "-vnc display start a VNC server on display
\n", QEMU_ARCH_ALL)
1137 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1139 Normally, QEMU uses SDL to display the VGA output. With this option,
1140 you can have QEMU listen on VNC display @var{display} and redirect the VGA
1141 display over the VNC session. It is very useful to enable the usb
1142 tablet device when using this option (option @option{-usbdevice
1143 tablet}). When using the VNC display, you must use the @option{-k}
1144 parameter to set the keyboard layout if you are not using en-us. Valid
1145 syntax for the @var{display} is
1149 @item @var{host}:@var{d}
1151 TCP connections will only be allowed from @var{host} on display @var{d}.
1152 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1153 be omitted in which case the server will accept connections from any host.
1155 @item unix:@var{path}
1157 Connections will be allowed over UNIX domain sockets where @var{path} is the
1158 location of a unix socket to listen for connections on.
1162 VNC is initialized but not started. The monitor @code{change} command
1163 can be used to later start the VNC server.
1167 Following the @var{display} value there may be one or more @var{option} flags
1168 separated by commas. Valid options are
1174 Connect to a listening VNC client via a ``reverse'' connection. The
1175 client is specified by the @var{display}. For reverse network
1176 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1177 is a TCP port number, not a display number.
1181 Opens an additional TCP listening port dedicated to VNC Websocket connections.
1182 By definition the Websocket port is 5700+@var{display}. If @var{host} is
1183 specified connections will only be allowed from this host.
1184 As an alternative the Websocket port could be specified by using
1185 @code{websocket}=@var{port}.
1186 TLS encryption for the Websocket connection is supported if the required
1187 certificates are specified with the VNC option @option{x509}.
1191 Require that password based authentication is used for client connections.
1193 The password must be set separately using the @code{set_password} command in
1194 the @ref{pcsys_monitor}. The syntax to change your password is:
1195 @code{set_password <protocol> <password>} where <protocol> could be either
1198 If you would like to change <protocol> password expiration, you should use
1199 @code{expire_password <protocol> <expiration-time>} where expiration time could
1200 be one of the following options: now, never, +seconds or UNIX time of
1201 expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1202 to make password expire on "Mon Apr
23 12:00:00 EDT
2012" (UNIX time for this
1205 You can also use keywords "now
" or "never" for the expiration time to
1206 allow <protocol> password to expire immediately or never expire.
1210 Require that client use TLS when communicating with the VNC server. This
1211 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1212 attack. It is recommended that this option be combined with either the
1213 @option{x509} or @option{x509verify} options.
1215 @item x509=@var{/path/to/certificate/dir}
1217 Valid if @option{tls} is specified. Require that x509 credentials are used
1218 for negotiating the TLS session. The server will send its x509 certificate
1219 to the client. It is recommended that a password be set on the VNC server
1220 to provide authentication of the client when this is used. The path following
1221 this option specifies where the x509 certificates are to be loaded from.
1222 See the @ref{vnc_security} section for details on generating certificates.
1224 @item x509verify=@var{/path/to/certificate/dir}
1226 Valid if @option{tls} is specified. Require that x509 credentials are used
1227 for negotiating the TLS session. The server will send its x509 certificate
1228 to the client, and request that the client send its own x509 certificate.
1229 The server will validate the client's certificate against the CA certificate,
1230 and reject clients when validation fails. If the certificate authority is
1231 trusted, this is a sufficient authentication mechanism. You may still wish
1232 to set a password on the VNC server as a second authentication layer. The
1233 path following this option specifies where the x509 certificates are to
1234 be loaded from. See the @ref{vnc_security} section for details on generating
1239 Require that the client use SASL to authenticate with the VNC server.
1240 The exact choice of authentication method used is controlled from the
1241 system / user's SASL configuration file for the 'qemu' service. This
1242 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1243 unprivileged user, an environment variable SASL_CONF_PATH can be used
1244 to make it search alternate locations for the service config.
1245 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1246 it is recommended that SASL always be combined with the 'tls' and
1247 'x509' settings to enable use of SSL and server certificates. This
1248 ensures a data encryption preventing compromise of authentication
1249 credentials. See the @ref{vnc_security} section for details on using
1250 SASL authentication.
1254 Turn on access control lists for checking of the x509 client certificate
1255 and SASL party. For x509 certs, the ACL check is made against the
1256 certificate's distinguished name. This is something that looks like
1257 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1258 made against the username, which depending on the SASL plugin, may
1259 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1260 When the @option{acl} flag is set, the initial access list will be
1261 empty, with a @code{deny} policy. Thus no one will be allowed to
1262 use the VNC server until the ACLs have been loaded. This can be
1263 achieved using the @code{acl} monitor command.
1267 Enable lossy compression methods (gradient, JPEG, ...). If this
1268 option is set, VNC client may receive lossy framebuffer updates
1269 depending on its encoding settings. Enabling this option can save
1270 a lot of bandwidth at the expense of quality.
1274 Disable adaptive encodings. Adaptive encodings are enabled by default.
1275 An adaptive encoding will try to detect frequently updated screen regions,
1276 and send updates in these regions using a lossy encoding (like JPEG).
1277 This can be really helpful to save bandwidth when playing videos. Disabling
1278 adaptive encodings restores the original static behavior of encodings
1281 @item share=[allow-exclusive|force-shared|ignore]
1283 Set display sharing policy. 'allow-exclusive' allows clients to ask
1284 for exclusive access. As suggested by the rfb spec this is
1285 implemented by dropping other connections. Connecting multiple
1286 clients in parallel requires all clients asking for a shared session
1287 (vncviewer: -shared switch). This is the default. 'force-shared'
1288 disables exclusive client access. Useful for shared desktop sessions,
1289 where you don't want someone forgetting specify -shared disconnect
1290 everybody else. 'ignore' completely ignores the shared flag and
1291 allows everybody connect unconditionally. Doesn't conform to the rfb
1292 spec but is traditional QEMU behavior.
1300 ARCHHEADING(, QEMU_ARCH_I386)
1302 ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1307 DEF("win2k
-hack
", 0, QEMU_OPTION_win2k_hack,
1308 "-win2k
-hack use it when installing Windows
2000 to avoid a disk full bug
\n",
1313 Use it when installing Windows 2000 to avoid a disk full bug. After
1314 Windows 2000 is installed, you no longer need this option (this option
1315 slows down the IDE transfers).
1318 HXCOMM Deprecated by -rtc
1319 DEF("rtc
-td
-hack
", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1321 DEF("no
-fd
-bootchk
", 0, QEMU_OPTION_no_fd_bootchk,
1322 "-no
-fd
-bootchk disable boot signature checking
for floppy disks
\n",
1325 @item -no-fd-bootchk
1326 @findex -no-fd-bootchk
1327 Disable boot signature checking for floppy disks in BIOS. May
1328 be needed to boot from old floppy disks.
1331 DEF("no
-acpi
", 0, QEMU_OPTION_no_acpi,
1332 "-no
-acpi disable ACPI
\n", QEMU_ARCH_I386)
1336 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1337 it if your guest OS complains about ACPI problems (PC target machine
1341 DEF("no
-hpet
", 0, QEMU_OPTION_no_hpet,
1342 "-no
-hpet disable HPET
\n", QEMU_ARCH_I386)
1346 Disable HPET support.
1349 DEF("acpitable
", HAS_ARG, QEMU_OPTION_acpitable,
1350 "-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"
1351 " ACPI table description
\n", QEMU_ARCH_I386)
1353 @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}]...]
1355 Add ACPI table with specified header fields and context from specified files.
1356 For file=, take whole ACPI table from the specified files, including all
1357 ACPI headers (possible overridden by other options).
1358 For data=, only data
1359 portion of the table is used, all header information is specified in the
1363 DEF("smbios
", HAS_ARG, QEMU_OPTION_smbios,
1364 "-smbios file
=binary
\n"
1365 " load SMBIOS entry from binary file
\n"
1366 "-smbios type
=0[,vendor
=str
][,version
=str
][,date
=str
][,release
=%d
.%d
][,uefi
=on|off
]\n"
1367 " specify SMBIOS type
0 fields
\n"
1368 "-smbios type
=1[,manufacturer
=str
][,product
=str
][,version
=str
][,serial
=str
]\n"
1369 " [,uuid
=uuid
][,sku
=str
][,family
=str
]\n"
1370 " specify SMBIOS type
1 fields
\n", QEMU_ARCH_I386)
1372 @item -smbios file=@var{binary}
1374 Load SMBIOS entry from binary file.
1376 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1377 Specify SMBIOS type 0 fields
1379 @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}]
1380 Specify SMBIOS type 1 fields
1388 DEFHEADING(Network options:)
1393 HXCOMM Legacy slirp options (now moved to -net user):
1395 DEF("tftp
", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1396 DEF("bootp
", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1397 DEF("redir
", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1399 DEF("smb
", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1403 DEF("net
", HAS_ARG, QEMU_OPTION_net,
1404 "-net nic
[,vlan
=n
][,macaddr
=mac
][,model
=type
][,name
=str
][,addr
=str
][,vectors
=v
]\n"
1405 " create a
new Network Interface Card and connect it to VLAN
'n'\n"
1407 "-net user
[,vlan
=n
][,name
=str
][,net
=addr
[/mask
]][,host
=addr
][,restrict
=on|off
]\n"
1408 " [,hostname
=host
][,dhcpstart
=addr
][,dns
=addr
][,dnssearch
=domain
][,tftp
=dir
]\n"
1409 " [,bootfile
=f
][,hostfwd
=rule
][,guestfwd
=rule
]"
1411 "[,smb
=dir
[,smbserver
=addr
]]\n"
1413 " connect the user mode network stack to VLAN
'n', configure its
\n"
1414 " DHCP server and enabled optional services
\n"
1417 "-net tap
[,vlan
=n
][,name
=str
],ifname
=name
\n"
1418 " connect the host TAP network
interface to VLAN
'n'\n"
1420 "-net tap
[,vlan
=n
][,name
=str
][,fd
=h
][,fds
=x
:y
:...:z
][,ifname
=name
][,script
=file
][,downscript
=dfile
][,helper
=helper
][,sndbuf
=nbytes
][,vnet_hdr
=on|off
][,vhost
=on|off
][,vhostfd
=h
][,vhostfds
=x
:y
:...:z
][,vhostforce
=on|off
][,queues
=n
]\n"
1421 " connect the host TAP network
interface to VLAN
'n'\n"
1422 " use network scripts
'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1423 " to configure it and
'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1424 " to deconfigure it
\n"
1425 " use
'[down]script=no' to disable script execution
\n"
1426 " use network helper
'helper' (default=" DEFAULT_BRIDGE_HELPER ") to
\n"
1428 " use
'fd=h' to connect to an already opened TAP
interface\n"
1429 " use
'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces
\n"
1430 " use
'sndbuf=nbytes' to limit the size of the send
buffer (the
\n"
1431 " default is disabled
'sndbuf=0' to enable flow control set
'sndbuf=1048576')\n"
1432 " use vnet_hdr
=off to avoid enabling the IFF_VNET_HDR tap flag
\n"
1433 " use vnet_hdr
=on to make the lack of IFF_VNET_HDR support an error condition
\n"
1434 " use vhost
=on to enable experimental
in kernel accelerator
\n"
1435 " (only has effect
for virtio guests which use MSIX
)\n"
1436 " use vhostforce
=on to force vhost on
for non
-MSIX virtio guests
\n"
1437 " use
'vhostfd=h' to connect to an already opened vhost net device
\n"
1438 " use
'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n"
1439 " use 'queues
=n
' to specify the number of queues to be created for multiqueue TAP\n"
1440 "-net bridge[,vlan=n][,name=str][,br=bridge][,helper=helper]\n"
1441 " connects a host TAP network interface to a host bridge device 'br
'\n"
1442 " (default=" DEFAULT_BRIDGE_INTERFACE ") using the program 'helper
'\n"
1443 " (default=" DEFAULT_BRIDGE_HELPER ")\n"
1446 "-net l2tpv3[,vlan=n][,name=str],src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport],txsession=txsession[,rxsession=rxsession][,ipv6=on/off][,udp=on/off][,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie][,rxcookie=rxcookie][,offset=offset]\n"
1447 " connect the VLAN to an Ethernet over L2TPv3 pseudowire\n"
1448 " Linux kernel 3.3+ as well as most routers can talk\n"
1449 " L2TPv3. This transport allows connecting a VM to a VM,\n"
1450 " VM to a router and even VM to Host. It is a nearly-universal\n"
1451 " standard (RFC3391). Note - this implementation uses static\n"
1452 " pre-configured tunnels (same as the Linux kernel).\n"
1453 " use 'src
=' to specify source address\n"
1454 " use 'dst
=' to specify destination address\n"
1455 " use 'udp
=on
' to specify udp encapsulation\n"
1456 " use 'srcport
=' to specify source udp port\n"
1457 " use 'dstport
=' to specify destination udp port\n"
1458 " use 'ipv6
=on
' to force v6\n"
1459 " L2TPv3 uses cookies to prevent misconfiguration as\n"
1460 " well as a weak security measure\n"
1461 " use 'rxcookie
=0x012345678' to specify a rxcookie\n"
1462 " use 'txcookie
=0x012345678' to specify a txcookie\n"
1463 " use 'cookie64
=on
' to set cookie size to 64 bit, otherwise 32\n"
1464 " use 'counter
=off
' to force a 'cut
-down
' L2TPv3 with no counter\n"
1465 " use 'pincounter
=on
' to work around broken counter handling in peer\n"
1466 " use 'offset
=X
' to add an extra offset between header and data\n"
1468 "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n"
1469 " connect the vlan 'n
' to another VLAN using a socket connection\n"
1470 "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1471 " connect the vlan 'n
' to multicast maddr and port\n"
1472 " use 'localaddr
=addr
' to specify the host address to send packets from\n"
1473 "-net socket[,vlan=n][,name=str][,fd=h][,udp=host:port][,localaddr=host:port]\n"
1474 " connect the vlan 'n
' to another VLAN using an UDP tunnel\n"
1476 "-net vde[,vlan=n][,name=str][,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1477 " connect the vlan 'n
' to port 'n
' of a vde switch running\n"
1478 " on host and listening for incoming connections on 'socketpath
'.\n"
1479 " Use group 'groupname
' and mode 'octalmode
' to change default\n"
1480 " ownership and permissions for communication port.\n"
1482 #ifdef CONFIG_NETMAP
1483 "-net netmap,ifname=name[,devname=nmname]\n"
1484 " attach to the existing netmap-enabled network interface 'name
', or to a\n"
1485 " VALE port (created on the fly) called 'name
' ('nmname
' is name of the \n"
1486 " netmap device, defaults to '/dev
/netmap
')\n"
1488 "-net dump[,vlan=n][,file=f][,len=n]\n"
1489 " dump traffic on vlan 'n
' to file 'f
' (max n bytes per packet)\n"
1490 "-net none use it alone to have zero network devices. If no -net option\n"
1491 " is provided, the default is '-net nic
-net user
'\n", QEMU_ARCH_ALL)
1492 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1502 #ifdef CONFIG_NETMAP
1507 "hubport],id=str[,option][,option][,...]\n", QEMU_ARCH_ALL)
1509 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1511 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1512 = 0 is the default). The NIC is an e1000 by default on the PC
1513 target. Optionally, the MAC address can be changed to @var{mac}, the
1514 device address set to @var{addr} (PCI cards only),
1515 and a @var{name} can be assigned for use in monitor commands.
1516 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1517 that the card should have; this option currently only affects virtio cards; set
1518 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1519 NIC is created. QEMU can emulate several different models of network card.
1520 Valid values for @var{type} are
1521 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1522 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1523 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1524 Not all devices are supported on all targets. Use @code{-net nic,model=help}
1525 for a list of available devices for your target.
1527 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
1529 @item -net user[,@var{option}][,@var{option}][,...]
1530 Use the user mode network stack which requires no administrator
1531 privilege to run. Valid options are:
1535 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1538 @item name=@var{name}
1539 Assign symbolic name for use in monitor commands.
1541 @item net=@var{addr}[/@var{mask}]
1542 Set IP network address the guest will see. Optionally specify the netmask,
1543 either in the form a.b.c.d or as number of valid top-most bits. Default is
1546 @item host=@var{addr}
1547 Specify the guest-visible address of the host. Default is the 2nd IP in the
1548 guest network, i.e. x.x.x.2.
1550 @item restrict=on|off
1551 If this option is enabled, the guest will be isolated, i.e. it will not be
1552 able to contact the host and no guest IP packets will be routed over the host
1553 to the outside. This option does not affect any explicitly set forwarding rules.
1555 @item hostname=@var{name}
1556 Specifies the client hostname reported by the built-in DHCP server.
1558 @item dhcpstart=@var{addr}
1559 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1560 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1562 @item dns=@var{addr}
1563 Specify the guest-visible address of the virtual nameserver. The address must
1564 be different from the host address. Default is the 3rd IP in the guest network,
1567 @item dnssearch=@var{domain}
1568 Provides an entry for the domain-search list sent by the built-in
1569 DHCP server. More than one domain suffix can be transmitted by specifying
1570 this option multiple times. If supported, this will cause the guest to
1571 automatically try to append the given domain suffix(es) in case a domain name
1572 can not be resolved.
1576 qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
1579 @item tftp=@var{dir}
1580 When using the user mode network stack, activate a built-in TFTP
1581 server. The files in @var{dir} will be exposed as the root of a TFTP server.
1582 The TFTP client on the guest must be configured in binary mode (use the command
1583 @code{bin} of the Unix TFTP client).
1585 @item bootfile=@var{file}
1586 When using the user mode network stack, broadcast @var{file} as the BOOTP
1587 filename. In conjunction with @option{tftp}, this can be used to network boot
1588 a guest from a local directory.
1590 Example (using pxelinux):
1592 qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1595 @item smb=@var{dir}[,smbserver=@var{addr}]
1596 When using the user mode network stack, activate a built-in SMB
1597 server so that Windows OSes can access to the host files in @file{@var{dir}}
1598 transparently. The IP address of the SMB server can be set to @var{addr}. By
1599 default the 4th IP in the guest network is used, i.e. x.x.x.4.
1601 In the guest Windows OS, the line:
1605 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1606 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1608 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
1610 Note that a SAMBA server must be installed on the host OS.
1611 QEMU was tested successfully with smbd versions from Red Hat 9,
1612 Fedora Core 3 and OpenSUSE 11.x.
1614 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1615 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1616 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1617 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1618 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1619 be bound to a specific host interface. If no connection type is set, TCP is
1620 used. This option can be given multiple times.
1622 For example, to redirect host X11 connection from screen 1 to guest
1623 screen 0, use the following:
1627 qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1628 # this host xterm should open in the guest X11 server
1632 To redirect telnet connections from host port 5555 to telnet port on
1633 the guest, use the following:
1637 qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
1638 telnet localhost 5555
1641 Then when you use on the host @code{telnet localhost 5555}, you
1642 connect to the guest telnet server.
1644 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1645 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
1646 Forward guest TCP connections to the IP address @var{server} on port @var{port}
1647 to the character device @var{dev} or to a program executed by @var{cmd:command}
1648 which gets spawned for each connection. This option can be given multiple times.
1650 You can either use a chardev directly and have that one used throughout QEMU's
1651 lifetime
, like
in the following example
:
1654 # open
10.10.1.1:4321 on bootup
, connect
10.0.2.100:1234 to it whenever
1655 # the guest accesses it
1656 qemu
-net user
,guestfwd
=tcp
:10.0.2.100:1234-tcp
:10.10.1.1:4321 [...]
1659 Or you can execute a command on every TCP connection established by the guest
,
1660 so that QEMU behaves similar to an inetd process
for that virtual server
:
1663 # call
"netcat 10.10.1.1 4321" on every TCP connection to
10.0.2.100:1234
1664 # and connect the TCP stream to its stdin
/stdout
1665 qemu
-net
'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
1670 Note
: Legacy stand
-alone options
-tftp
, -bootp
, -smb and
-redir are still
1671 processed and applied to
-net user
. Mixing them with the
new configuration
1672 syntax gives undefined results
. Their use
for new applications is discouraged
1673 as they will be removed from future versions
.
1675 @item
-netdev tap
,id
=@
var{id
}[,fd
=@
var{h
}][,ifname
=@
var{name
}][,script
=@
var{file
}][,downscript
=@
var{dfile
}][,helper
=@
var{helper
}]
1676 @item
-net tap
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}][,ifname
=@
var{name
}][,script
=@
var{file
}][,downscript
=@
var{dfile
}][,helper
=@
var{helper
}]
1677 Connect the host TAP network
interface @
var{name
} to VLAN @
var{n
}.
1679 Use the network script @
var{file
} to configure it and the network script
1680 @
var{dfile
} to deconfigure it
. If @
var{name
} is not provided
, the OS
1681 automatically provides one
. The
default network configure script is
1682 @file
{/etc
/qemu
-ifup
} and the
default network deconfigure script is
1683 @file
{/etc
/qemu
-ifdown
}. Use @option
{script
=no
} or @option
{downscript
=no
}
1684 to disable script execution
.
1686 If running QEMU as an unprivileged user
, use the network helper
1687 @
var{helper
} to configure the TAP
interface. The
default network
1688 helper executable is @file
{/path
/to
/qemu
-bridge
-helper
}.
1690 @option
{fd
}=@
var{h
} can be used to specify the handle of an already
1691 opened host TAP
interface.
1696 #launch a QEMU instance with the
default network script
1697 qemu
-system
-i386 linux
.img
-net nic
-net tap
1701 #launch a QEMU instance with two NICs
, each one connected
1703 qemu
-system
-i386 linux
.img \
1704 -net nic
,vlan
=0 -net tap
,vlan
=0,ifname
=tap0 \
1705 -net nic
,vlan
=1 -net tap
,vlan
=1,ifname
=tap1
1709 #launch a QEMU instance with the
default network helper to
1710 #connect a TAP device to bridge br0
1711 qemu
-system
-i386 linux
.img \
1712 -net nic
-net tap
,"helper=/path/to/qemu-bridge-helper"
1715 @item
-netdev bridge
,id
=@
var{id
}[,br
=@
var{bridge
}][,helper
=@
var{helper
}]
1716 @item
-net bridge
[,vlan
=@
var{n
}][,name
=@
var{name
}][,br
=@
var{bridge
}][,helper
=@
var{helper
}]
1717 Connect a host TAP network
interface to a host bridge device
.
1719 Use the network helper @
var{helper
} to configure the TAP
interface and
1720 attach it to the bridge
. The
default network helper executable is
1721 @file
{/path
/to
/qemu
-bridge
-helper
} and the
default bridge
1722 device is @file
{br0
}.
1727 #launch a QEMU instance with the
default network helper to
1728 #connect a TAP device to bridge br0
1729 qemu
-system
-i386 linux
.img
-net bridge
-net nic
,model
=virtio
1733 #launch a QEMU instance with the
default network helper to
1734 #connect a TAP device to bridge qemubr0
1735 qemu
-system
-i386 linux
.img
-net bridge
,br
=qemubr0
-net nic
,model
=virtio
1738 @item
-netdev socket
,id
=@
var{id
}[,fd
=@
var{h
}][,listen
=[@
var{host
}]:@
var{port
}][,connect
=@
var{host
}:@
var{port
}]
1739 @item
-net socket
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}] [,listen
=[@
var{host
}]:@
var{port
}][,connect
=@
var{host
}:@
var{port
}]
1741 Connect the VLAN @
var{n
} to a remote VLAN
in another QEMU virtual
1742 machine
using a TCP socket connection
. If @option
{listen
} is
1743 specified
, QEMU waits
for incoming connections on @
var{port
}
1744 (@
var{host
} is optional
). @option
{connect
} is used to connect to
1745 another QEMU instance
using the @option
{listen
} option
. @option
{fd
}=@
var{h
}
1746 specifies an already opened TCP socket
.
1750 # launch a first QEMU instance
1751 qemu
-system
-i386 linux
.img \
1752 -net nic
,macaddr
=52:54:00:12:34:56 \
1753 -net socket
,listen
=:1234
1754 # connect the VLAN
0 of
this instance to the VLAN
0
1755 # of the first instance
1756 qemu
-system
-i386 linux
.img \
1757 -net nic
,macaddr
=52:54:00:12:34:57 \
1758 -net socket
,connect
=127.0.0.1:1234
1761 @item
-netdev socket
,id
=@
var{id
}[,fd
=@
var{h
}][,mcast
=@
var{maddr
}:@
var{port
}[,localaddr
=@
var{addr
}]]
1762 @item
-net socket
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}][,mcast
=@
var{maddr
}:@
var{port
}[,localaddr
=@
var{addr
}]]
1764 Create a VLAN @
var{n
} shared with another QEMU virtual
1765 machines
using a UDP multicast socket
, effectively making a bus
for
1766 every QEMU with same multicast address @
var{maddr
} and @
var{port
}.
1770 Several QEMU can be running on different hosts and share same
bus (assuming
1771 correct multicast setup
for these hosts
).
1773 mcast support is compatible with User Mode
Linux (argument @option
{eth@
var{N
}=mcast
}), see
1774 @url
{http
://user-mode-linux.sf.net}.
1776 Use @option
{fd
=h
} to specify an already opened UDP multicast socket
.
1781 # launch one QEMU instance
1782 qemu
-system
-i386 linux
.img \
1783 -net nic
,macaddr
=52:54:00:12:34:56 \
1784 -net socket
,mcast
=230.0.0.1:1234
1785 # launch another QEMU instance on same
"bus"
1786 qemu
-system
-i386 linux
.img \
1787 -net nic
,macaddr
=52:54:00:12:34:57 \
1788 -net socket
,mcast
=230.0.0.1:1234
1789 # launch yet another QEMU instance on same
"bus"
1790 qemu
-system
-i386 linux
.img \
1791 -net nic
,macaddr
=52:54:00:12:34:58 \
1792 -net socket
,mcast
=230.0.0.1:1234
1795 Example (User Mode Linux compat
.):
1797 # launch QEMU
instance (note mcast address selected
1799 qemu-system-i386 linux.img \
1800 -net nic,macaddr=52:54:00:12:34:56 \
1801 -net socket,mcast=239.192.168.1:1102
1803 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
1806 Example (send packets from host's
1.2.3.4):
1808 qemu
-system
-i386 linux
.img \
1809 -net nic
,macaddr
=52:54:00:12:34:56 \
1810 -net socket
,mcast
=239.192.168.1:1102,localaddr
=1.2.3.4
1813 @item
-netdev l2tpv3
,id
=@
var{id
},src
=@
var{srcaddr
},dst
=@
var{dstaddr
}[,srcport
=@
var{srcport
}][,dstport
=@
var{dstport
}],txsession
=@
var{txsession
}[,rxsession
=@
var{rxsession
}][,ipv6
][,udp
][,cookie64
][,counter
][,pincounter
][,txcookie
=@
var{txcookie
}][,rxcookie
=@
var{rxcookie
}][,offset
=@
var{offset
}]
1814 @item
-net l2tpv3
[,vlan
=@
var{n
}][,name
=@
var{name
}],src
=@
var{srcaddr
},dst
=@
var{dstaddr
}[,srcport
=@
var{srcport
}][,dstport
=@
var{dstport
}],txsession
=@
var{txsession
}[,rxsession
=@
var{rxsession
}][,ipv6
][,udp
][,cookie64
][,counter
][,pincounter
][,txcookie
=@
var{txcookie
}][,rxcookie
=@
var{rxcookie
}][,offset
=@
var{offset
}]
1815 Connect VLAN @
var{n
} to L2TPv3 pseudowire
. L2TPv3 (RFC3391
) is a popular
1816 protocol to transport
Ethernet (and other Layer
2) data frames between
1817 two systems
. It is present
in routers
, firewalls and the Linux kernel
1818 (from version
3.3 onwards
).
1820 This transport allows a VM to communicate to another VM
, router or firewall directly
.
1822 @item src
=@
var{srcaddr
}
1823 source
address (mandatory
)
1824 @item dst
=@
var{dstaddr
}
1825 destination
address (mandatory
)
1827 select udp
encapsulation (default is ip
).
1828 @item srcport
=@
var{srcport
}
1830 @item dstport
=@
var{dstport
}
1831 destination udp port
.
1833 force v6
, otherwise defaults to v4
.
1834 @item rxcookie
=@
var{rxcookie
}
1835 @item txcookie
=@
var{txcookie
}
1836 Cookies are a weak form of security
in the l2tpv3 specification
.
1837 Their
function is mostly to prevent misconfiguration
. By
default they are
32
1840 Set cookie size to
64 bit instead of the
default 32
1842 Force a
'cut-down' L2TPv3 with no counter as
in
1843 draft
-mkonstan
-l2tpext
-keyed
-ipv6
-tunnel
-00
1845 Work around broken counter handling
in peer
. This may also help on
1846 networks which have packet reorder
.
1847 @item offset
=@
var{offset
}
1848 Add an extra offset between header and data
1850 For example
, to attach a VM running on host
4.3.2.1 via L2TPv3 to the bridge br
-lan
1851 on the remote Linux host
1.2.3.4:
1853 # Setup tunnel on linux host
using raw ip as encapsulation
1855 ip l2tp add tunnel remote
4.3.2.1 local
1.2.3.4 tunnel_id
1 peer_tunnel_id
1 \
1856 encap udp udp_sport
16384 udp_dport
16384
1857 ip l2tp add session tunnel_id
1 name vmtunnel0 session_id \
1858 0xFFFFFFFF peer_session_id
0xFFFFFFFF
1859 ifconfig vmtunnel0 mtu
1500
1860 ifconfig vmtunnel0 up
1861 brctl addif br
-lan vmtunnel0
1865 # launch QEMU instance
- if your network has reorder or is very lossy add
,pincounter
1867 qemu
-system
-i386 linux
.img
-net nic
-net l2tpv3
,src
=4.2.3.1,dst
=1.2.3.4,udp
,srcport
=16384,dstport
=16384,rxsession
=0xffffffff,txsession
=0xffffffff,counter
1872 @item
-netdev vde
,id
=@
var{id
}[,sock
=@
var{socketpath
}][,port
=@
var{n
}][,group
=@
var{groupname
}][,mode
=@
var{octalmode
}]
1873 @item
-net vde
[,vlan
=@
var{n
}][,name
=@
var{name
}][,sock
=@
var{socketpath
}] [,port
=@
var{n
}][,group
=@
var{groupname
}][,mode
=@
var{octalmode
}]
1874 Connect VLAN @
var{n
} to PORT @
var{n
} of a vde
switch running on host and
1875 listening
for incoming connections on @
var{socketpath
}. Use GROUP @
var{groupname
}
1876 and MODE @
var{octalmode
} to change
default ownership and permissions
for
1877 communication port
. This option is only available
if QEMU has been compiled
1878 with vde support enabled
.
1883 vde_switch
-F
-sock
/tmp
/myswitch
1884 # launch QEMU instance
1885 qemu
-system
-i386 linux
.img
-net nic
-net vde
,sock
=/tmp
/myswitch
1888 @item
-netdev hubport
,id
=@
var{id
},hubid
=@
var{hubid
}
1890 Create a hub port on QEMU
"vlan" @
var{hubid
}.
1892 The hubport netdev lets you connect a NIC to a QEMU
"vlan" instead of a single
1893 netdev
. @code
{-net
} and @code
{-device
} with parameter @option
{vlan
} create the
1894 required hub automatically
.
1896 @item
-netdev vhost
-user
,chardev
=@
var{id
}[,vhostforce
=on|off
]
1898 Establish a vhost
-user netdev
, backed by a chardev @
var{id
}. The chardev should
1899 be a unix domain socket backed one
. The vhost
-user uses a specifically defined
1900 protocol to pass vhost ioctl replacement messages to an application on the other
1901 end of the socket
. On non
-MSIX guests
, the feature can be forced with
1906 qemu
-m
512 -object memory
-backend
-file
,id
=mem
,size
=512M
,mem
-path
=/hugetlbfs
,share
=on \
1907 -numa node
,memdev
=mem \
1908 -chardev socket
,path
=/path
/to
/socket \
1909 -netdev type
=vhost
-user
,id
=net0
,chardev
=chr0 \
1910 -device virtio
-net
-pci
,netdev
=net0
1913 @item
-net dump
[,vlan
=@
var{n
}][,file
=@
var{file
}][,len
=@
var{len
}]
1914 Dump network traffic on VLAN @
var{n
} to file @
var{file
} (@file
{qemu
-vlan0
.pcap
} by
default).
1915 At most @
var{len
} bytes (64k by
default) per packet are stored
. The file format is
1916 libpcap
, so it can be analyzed with tools such as tcpdump or Wireshark
.
1919 Indicate that no network devices should be configured
. It is used to
1920 override the
default configuration (@option
{-net nic
-net user
}) which
1921 is activated
if no @option
{-net
} options are provided
.
1929 DEFHEADING(Character device options
:)
1932 The general form of a character device option is
:
1936 DEF("chardev", HAS_ARG
, QEMU_OPTION_chardev
,
1937 "-chardev null,id=id[,mux=on|off]\n"
1938 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
1939 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off] (tcp)\n"
1940 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off] (unix)\n"
1941 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
1942 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
1943 "-chardev msmouse,id=id[,mux=on|off]\n"
1944 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
1946 "-chardev ringbuf,id=id[,size=size]\n"
1947 "-chardev file,id=id,path=path[,mux=on|off]\n"
1948 "-chardev pipe,id=id,path=path[,mux=on|off]\n"
1950 "-chardev console,id=id[,mux=on|off]\n"
1951 "-chardev serial,id=id,path=path[,mux=on|off]\n"
1953 "-chardev pty,id=id[,mux=on|off]\n"
1954 "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n"
1956 #ifdef CONFIG_BRLAPI
1957 "-chardev braille,id=id[,mux=on|off]\n"
1959 #
if defined(__linux__
) ||
defined(__sun__
) ||
defined(__FreeBSD__
) \
1960 ||
defined(__NetBSD__
) ||
defined(__OpenBSD__
) ||
defined(__DragonFly__
)
1961 "-chardev serial,id=id,path=path[,mux=on|off]\n"
1962 "-chardev tty,id=id,path=path[,mux=on|off]\n"
1964 #
if defined(__linux__
) ||
defined(__FreeBSD__
) ||
defined(__DragonFly__
)
1965 "-chardev parallel,id=id,path=path[,mux=on|off]\n"
1966 "-chardev parport,id=id,path=path[,mux=on|off]\n"
1968 #
if defined(CONFIG_SPICE
)
1969 "-chardev spicevmc,id=id,name=name[,debug=debug]\n"
1970 "-chardev spiceport,id=id,name=name[,debug=debug]\n"
1976 @item
-chardev @
var{backend
} ,id
=@
var{id
} [,mux
=on|off
] [,@
var{options
}]
1997 The specific backend will determine the applicable options
.
1999 All devices must have an id
, which can be any string up to
127 characters long
.
2000 It is used to uniquely identify
this device
in other command line directives
.
2002 A character device may be used
in multiplexing mode by multiple front
-ends
.
2003 The key sequence of @key
{Control
-a
} and @key
{c
} will rotate the input focus
2004 between attached front
-ends
. Specify @option
{mux
=on
} to enable
this mode
.
2006 Options to each backend are described below
.
2008 @item
-chardev
null ,id
=@
var{id
}
2009 A void device
. This device will not emit any data
, and will drop any data it
2010 receives
. The
null backend does not take any options
.
2012 @item
-chardev socket
,id
=@
var{id
} [@
var{TCP options
} or @
var{unix options
}] [,server
] [,nowait
] [,telnet
] [,reconnect
=@
var{seconds
}]
2014 Create a two
-way stream socket
, which can be either a TCP or a unix socket
. A
2015 unix socket will be created
if @option
{path
} is specified
. Behaviour is
2016 undefined
if TCP options are specified
for a unix socket
.
2018 @option
{server
} specifies that the socket shall be a listening socket
.
2020 @option
{nowait
} specifies that QEMU should not block waiting
for a client to
2021 connect to a listening socket
.
2023 @option
{telnet
} specifies that traffic on the socket should interpret telnet
2026 @option
{reconnect
} sets the timeout
for reconnecting on non
-server sockets when
2027 the remote end goes away
. qemu will delay
this many seconds and then attempt
2028 to reconnect
. Zero disables reconnecting
, and is the
default.
2030 TCP and unix socket options are given below
:
2034 @item TCP options
: port
=@
var{port
} [,host
=@
var{host
}] [,to
=@
var{to
}] [,ipv4
] [,ipv6
] [,nodelay
]
2036 @option
{host
} for a listening socket specifies the local address to be bound
.
2037 For a connecting socket species the remote host to connect to
. @option
{host
} is
2038 optional
for listening sockets
. If not specified it defaults to @code
{0.0.0.0}.
2040 @option
{port
} for a listening socket specifies the local port to be bound
. For a
2041 connecting socket specifies the port on the remote host to connect to
.
2042 @option
{port
} can be given as either a port number or a service name
.
2043 @option
{port
} is required
.
2045 @option
{to
} is only relevant to listening sockets
. If it is specified
, and
2046 @option
{port
} cannot be bound
, QEMU will attempt to bind to subsequent ports up
2047 to and including @option
{to
} until it succeeds
. @option
{to
} must be specified
2050 @option
{ipv4
} and @option
{ipv6
} specify that either IPv4 or IPv6 must be used
.
2051 If neither is specified the socket may use either protocol
.
2053 @option
{nodelay
} disables the Nagle algorithm
.
2055 @item unix options
: path
=@
var{path
}
2057 @option
{path
} specifies the local path of the unix socket
. @option
{path
} is
2062 @item
-chardev udp
,id
=@
var{id
} [,host
=@
var{host
}] ,port
=@
var{port
} [,localaddr
=@
var{localaddr
}] [,localport
=@
var{localport
}] [,ipv4
] [,ipv6
]
2064 Sends all traffic from the guest to a remote host over UDP
.
2066 @option
{host
} specifies the remote host to connect to
. If not specified it
2067 defaults to @code
{localhost
}.
2069 @option
{port
} specifies the port on the remote host to connect to
. @option
{port
}
2072 @option
{localaddr
} specifies the local address to bind to
. If not specified it
2073 defaults to @code
{0.0.0.0}.
2075 @option
{localport
} specifies the local port to bind to
. If not specified any
2076 available local port will be used
.
2078 @option
{ipv4
} and @option
{ipv6
} specify that either IPv4 or IPv6 must be used
.
2079 If neither is specified the device may use either protocol
.
2081 @item
-chardev msmouse
,id
=@
var{id
}
2083 Forward QEMU
's emulated msmouse events to the guest. @option{msmouse} does not
2086 @item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
2088 Connect to a QEMU text console. @option{vc} may optionally be given a specific
2091 @option{width} and @option{height} specify the width and height respectively of
2092 the console, in pixels.
2094 @option{cols} and @option{rows} specify that the console be sized to fit a text
2095 console with the given dimensions.
2097 @item -chardev ringbuf ,id=@var{id} [,size=@var{size}]
2099 Create a ring buffer with fixed size @option{size}.
2100 @var{size} must be a power of two, and defaults to @code{64K}).
2102 @item -chardev file ,id=@var{id} ,path=@var{path}
2104 Log all traffic received from the guest to a file.
2106 @option{path} specifies the path of the file to be opened. This file will be
2107 created if it does not already exist, and overwritten if it does. @option{path}
2110 @item -chardev pipe ,id=@var{id} ,path=@var{path}
2112 Create a two-way connection to the guest. The behaviour differs slightly between
2113 Windows hosts and other hosts:
2115 On Windows, a single duplex pipe will be created at
2116 @file{\\.pipe\@option{path}}.
2118 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
2119 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
2120 received by the guest. Data written by the guest can be read from
2121 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
2124 @option{path} forms part of the pipe path as described above. @option{path} is
2127 @item -chardev console ,id=@var{id}
2129 Send traffic from the guest to QEMU's standard output
. @option
{console
} does not
2132 @option
{console
} is only available on Windows hosts
.
2134 @item
-chardev serial
,id
=@
var{id
} ,path
=@option
{path
}
2136 Send traffic from the guest to a serial device on the host
.
2138 On Unix hosts serial will actually accept any tty device
,
2139 not only serial lines
.
2141 @option
{path
} specifies the name of the serial device to open
.
2143 @item
-chardev pty
,id
=@
var{id
}
2145 Create a
new pseudo
-terminal on the host and connect to it
. @option
{pty
} does
2146 not take any options
.
2148 @option
{pty
} is not available on Windows hosts
.
2150 @item
-chardev stdio
,id
=@
var{id
} [,signal
=on|off
]
2151 Connect to standard input and standard output of the QEMU process
.
2153 @option
{signal
} controls
if signals are enabled on the terminal
, that includes
2154 exiting QEMU with the key sequence @key
{Control
-c
}. This option is enabled by
2155 default, use @option
{signal
=off
} to disable it
.
2157 @option
{stdio
} is not available on Windows hosts
.
2159 @item
-chardev braille
,id
=@
var{id
}
2161 Connect to a local BrlAPI server
. @option
{braille
} does not take any options
.
2163 @item
-chardev tty
,id
=@
var{id
} ,path
=@
var{path
}
2165 @option
{tty
} is only available on Linux
, Sun
, FreeBSD
, NetBSD
, OpenBSD and
2166 DragonFlyBSD hosts
. It is an alias
for @option
{serial
}.
2168 @option
{path
} specifies the path to the tty
. @option
{path
} is required
.
2170 @item
-chardev parallel
,id
=@
var{id
} ,path
=@
var{path
}
2171 @item
-chardev parport
,id
=@
var{id
} ,path
=@
var{path
}
2173 @option
{parallel
} is only available on Linux
, FreeBSD and DragonFlyBSD hosts
.
2175 Connect to a local parallel port
.
2177 @option
{path
} specifies the path to the parallel port device
. @option
{path
} is
2180 @item
-chardev spicevmc
,id
=@
var{id
} ,debug
=@
var{debug
}, name
=@
var{name
}
2182 @option
{spicevmc
} is only available when spice support is built
in.
2184 @option
{debug
} debug level
for spicevmc
2186 @option
{name
} name of spice channel to connect to
2188 Connect to a spice virtual machine channel
, such as vdiport
.
2190 @item
-chardev spiceport
,id
=@
var{id
} ,debug
=@
var{debug
}, name
=@
var{name
}
2192 @option
{spiceport
} is only available when spice support is built
in.
2194 @option
{debug
} debug level
for spicevmc
2196 @option
{name
} name of spice port to connect to
2198 Connect to a spice port
, allowing a Spice client to handle the traffic
2199 identified by a
name (preferably a fqdn
).
2207 DEFHEADING(Device URL Syntax
:)
2210 In addition to
using normal file images
for the emulated storage devices
,
2211 QEMU can also use networked resources such as iSCSI devices
. These are
2212 specified
using a special URL syntax
.
2216 iSCSI support allows QEMU to access iSCSI resources directly and use as
2217 images
for the guest storage
. Both disk and cdrom images are supported
.
2219 Syntax
for specifying iSCSI LUNs is
2220 ``iscsi
://<target-ip>[:<port>]/<target-iqn>/<lun>''
2222 By
default qemu will use the iSCSI initiator
-name
2223 'iqn.2008-11.org.linux-kvm[:<name>]' but
this can also be set from the command
2224 line or a configuration file
.
2227 Example (without authentication
):
2229 qemu
-system
-i386
-iscsi initiator
-name
=iqn
.2001-04.com
.example
:my
-initiator \
2230 -cdrom iscsi
://192.0.2.1/iqn.2001-04.com.example/2 \
2231 -drive file
=iscsi
://192.0.2.1/iqn.2001-04.com.example/1
2234 Example (CHAP username
/password via URL
):
2236 qemu
-system
-i386
-drive file
=iscsi
://user%password@@192.0.2.1/iqn.2001-04.com.example/1
2239 Example (CHAP username
/password via environment variables
):
2241 LIBISCSI_CHAP_USERNAME
="user" \
2242 LIBISCSI_CHAP_PASSWORD
="password" \
2243 qemu
-system
-i386
-drive file
=iscsi
://192.0.2.1/iqn.2001-04.com.example/1
2246 iSCSI support is an optional feature of QEMU and only available when
2247 compiled and linked against libiscsi
.
2249 DEF("iscsi", HAS_ARG
, QEMU_OPTION_iscsi
,
2250 "-iscsi [user=user][,password=password]\n"
2251 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
2252 " [,initiator-name=initiator-iqn][,id=target-iqn]\n"
2253 " iSCSI session parameters\n", QEMU_ARCH_ALL
)
2256 iSCSI parameters such as username and password can also be specified via
2257 a configuration file
. See qemu
-doc
for more information and examples
.
2260 QEMU supports
NBD (Network Block Devices
) both
using TCP protocol as well
2261 as Unix Domain Sockets
.
2263 Syntax
for specifying a NBD device
using TCP
2264 ``nbd
:<server
-ip
>:<port
>[:exportname
=<export
>]''
2266 Syntax
for specifying a NBD device
using Unix Domain Sockets
2267 ``nbd
:unix
:<domain
-socket
>[:exportname
=<export
>]''
2272 qemu
-system
-i386
--drive file
=nbd
:192.0.2.1:30000
2275 Example
for Unix Domain Sockets
2277 qemu
-system
-i386
--drive file
=nbd
:unix
:/tmp
/nbd
-socket
2281 QEMU supports
SSH (Secure Shell
) access to remote disks
.
2285 qemu
-system
-i386
-drive file
=ssh
://user@@host/path/to/disk.img
2286 qemu
-system
-i386
-drive file
.driver
=ssh
,file
.user
=user
,file
.host
=host
,file
.port
=22,file
.path
=/path
/to
/disk
.img
2289 Currently authentication must be done
using ssh
-agent
. Other
2290 authentication methods may be supported
in future
.
2293 Sheepdog is a distributed storage system
for QEMU
.
2294 QEMU supports
using either local sheepdog devices or remote networked
2297 Syntax
for specifying a sheepdog device
2299 sheepdog
[+tcp|
+unix
]://[host:port]/vdiname[?socket=path][#snapid|#tag]
2304 qemu
-system
-i386
--drive file
=sheepdog
://192.0.2.1:30000/MyVirtualMachine
2307 See also @url
{http
://http://www.osrg.net/sheepdog/}.
2310 GlusterFS is an user space distributed file system
.
2311 QEMU supports the use of GlusterFS volumes
for hosting VM disk images
using
2312 TCP
, Unix Domain Sockets and RDMA transport protocols
.
2314 Syntax
for specifying a VM disk image on GlusterFS volume is
2316 gluster
[+transport
]://[server[:port]]/volname/image[?socket=...]
2322 qemu
-system
-x86_64
--drive file
=gluster
://192.0.2.1/testvol/a.img
2325 See also @url
{http
://www.gluster.org}.
2327 @item HTTP
/HTTPS
/FTP
/FTPS
/TFTP
2328 QEMU supports read
-only access to files accessed over
http(s
), ftp(s
) and tftp
.
2330 Syntax
using a single filename
:
2332 <protocol
>://[<username>[:<password>]@@]<host>/<path>
2338 'http', 'https', 'ftp', 'ftps', or
'tftp'.
2341 Optional username
for authentication to the remote server
.
2344 Optional password
for authentication to the remote server
.
2347 Address of the remote server
.
2350 Path on the remote server
, including any query string
.
2353 The following options are also supported
:
2356 The full URL when passing options to the driver explicitly
.
2359 The amount of data to read ahead with each range request to the remote server
.
2360 This value may optionally have the suffix
'T', 'G', 'M', 'K', 'k' or
'b'. If it
2361 does not have a suffix
, it will be assumed to be
in bytes
. The value must be a
2362 multiple of
512 bytes
. It defaults to
256k
.
2365 Whether to verify the remote server
's certificate when connecting over SSL. It
2366 can have the value 'on
' or 'off
'. It defaults to 'on
'.
2369 Send this cookie (it can also be a list of cookies separated by ';') with
2370 each outgoing request. Only supported when using protocols such as HTTP
2371 which support cookies, otherwise ignored.
2374 Set the timeout in seconds of the CURL connection. This timeout is the time
2375 that CURL waits for a response from the remote server to get the size of the
2376 image to be downloaded. If not set, the default timeout of 5 seconds is used.
2379 Note that when passing options to qemu explicitly, @option{driver} is the value
2382 Example: boot from a remote Fedora 20 live ISO image
2384 qemu-system-x86_64 --drive media=cdrom,file=http://dl.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
2386 qemu-system-x86_64 --drive media=cdrom,file.driver=http,file.url=http://dl.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
2389 Example: boot from a remote Fedora 20 cloud image using a local overlay for
2390 writes, copy-on-read, and a readahead of 64k
2392 qemu-img create -f qcow2 -o backing_file='json
:@
{"file.driver":"http",, "file.url":"https://dl.fedoraproject.org/pub/fedora/linux/releases/20/Images/x86_64/Fedora-x86_64-20-20131211.1-sda.qcow2",, "file.readahead":"64k"@
}' /tmp/Fedora-x86_64-20-20131211.1-sda.qcow2
2394 qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on
2397 Example: boot from an image stored on a VMware vSphere server with a self-signed
2398 certificate using a local overlay for writes, a readahead of 64k and a timeout
2401 qemu-img create -f qcow2 -o backing_file='json
:@
{"file.driver":"https",, "file.url":"https://user:password@@vsphere.example.com/folder/test/test-flat.vmdk?dcPath=Datacenter&dsName=datastore1",, "file.sslverify":"off",, "file.readahead":"64k",, "file.timeout":10@
}' /tmp/test.qcow2
2403 qemu-system-x86_64 -drive file=/tmp/test.qcow2
2411 DEFHEADING(Bluetooth(R) options:)
2416 DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
2417 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands
\n" \
2418 "-bt hci
,host
[:id
]\n" \
2419 " use host
's HCI with the given name\n" \
2420 "-bt hci[,vlan=n]\n" \
2421 " emulate a standard HCI in virtual scatternet 'n
'\n" \
2422 "-bt vhci[,vlan=n]\n" \
2423 " add host computer to virtual scatternet 'n
' using VHCI\n" \
2424 "-bt device:dev[,vlan=n]\n" \
2425 " emulate a bluetooth device 'dev
' in scatternet 'n
'\n",
2430 Defines the function of the corresponding Bluetooth HCI. -bt options
2431 are matched with the HCIs present in the chosen machine type. For
2432 example when emulating a machine with only one HCI built into it, only
2433 the first @code{-bt hci[...]} option is valid and defines the HCI's
2434 logic
. The Transport Layer is decided by the machine type
. Currently
2435 the machines @code
{n800
} and @code
{n810
} have one HCI and all other
2439 The following three types are recognized
:
2443 (default) The corresponding Bluetooth HCI assumes no internal logic
2444 and will not respond to any HCI commands or emit events
.
2446 @item
-bt hci
,host
[:@
var{id
}]
2447 (@code
{bluez
} only
) The corresponding HCI passes commands
/ events
2448 to
/ from the physical HCI identified by the name @
var{id
} (default:
2449 @code
{hci0
}) on the computer running QEMU
. Only available on @code
{bluez
}
2450 capable systems like Linux
.
2452 @item
-bt hci
[,vlan
=@
var{n
}]
2453 Add a virtual
, standard HCI that will participate
in the Bluetooth
2454 scatternet @
var{n
} (default @code
{0}). Similarly to @option
{-net
}
2455 VLANs
, devices inside a bluetooth network @
var{n
} can only communicate
2456 with other devices
in the same
network (scatternet
).
2459 @item
-bt vhci
[,vlan
=@
var{n
}]
2460 (Linux
-host only
) Create a HCI
in scatternet @
var{n
} (default 0) attached
2461 to the host bluetooth stack instead of to the emulated target
. This
2462 allows the host and target machines to participate
in a common scatternet
2463 and communicate
. Requires the Linux @code
{vhci
} driver installed
. Can
2464 be used as following
:
2467 qemu
-system
-i386
[...OPTIONS
...] -bt hci
,vlan
=5 -bt vhci
,vlan
=5
2470 @item
-bt device
:@
var{dev
}[,vlan
=@
var{n
}]
2471 Emulate a bluetooth device @
var{dev
} and place it
in network @
var{n
}
2472 (default @code
{0}). QEMU can only emulate one type of bluetooth devices
2477 Virtual wireless keyboard implementing the HIDP bluetooth profile
.
2487 DEFHEADING(TPM device options
:)
2489 DEF("tpmdev", HAS_ARG
, QEMU_OPTION_tpmdev
, \
2490 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
2491 " use path to provide path to a character device; default is /dev/tpm0\n"
2492 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
2493 " not provided it will be searched for in /sys/class/misc/tpm?/device\n",
2497 The general form of a TPM device option is
:
2500 @item
-tpmdev @
var{backend
} ,id
=@
var{id
} [,@
var{options
}]
2502 Backend type must be
:
2503 @option
{passthrough
}.
2505 The specific backend type will determine the applicable options
.
2506 The @code
{-tpmdev
} option creates the TPM backend and requires a
2507 @code
{-device
} option that specifies the TPM frontend
interface model
.
2509 Options to each backend are described below
.
2511 Use
'help' to print all available TPM backend types
.
2516 @item
-tpmdev passthrough
, id
=@
var{id
}, path
=@
var{path
}, cancel
-path
=@
var{cancel
-path
}
2518 (Linux
-host only
) Enable access to the host
's TPM using the passthrough
2521 @option{path} specifies the path to the host's TPM device
, i
.e
., on
2522 a Linux host
this would be @code
{/dev
/tpm0
}.
2523 @option
{path
} is optional and by
default @code
{/dev
/tpm0
} is used
.
2525 @option
{cancel
-path
} specifies the path to the host TPM device
's sysfs
2526 entry allowing for cancellation of an ongoing TPM command.
2527 @option{cancel-path} is optional and by default QEMU will search for the
2530 Some notes about using the host's TPM with the passthrough driver
:
2532 The TPM device accessed by the passthrough driver must not be
2533 used by any other application on the host
.
2535 Since the host
's firmware (BIOS/UEFI) has already initialized the TPM,
2536 the VM's
firmware (BIOS
/UEFI
) will not be able to initialize the
2537 TPM again and may therefore not show a TPM
-specific menu that would
2538 otherwise allow the user to configure the TPM
, e
.g
., allow the user to
2539 enable
/disable or activate
/deactivate the TPM
.
2540 Further
, if TPM ownership is released from within a VM then the host
's TPM
2541 will get disabled and deactivated. To enable and activate the
2542 TPM again afterwards, the host has to be rebooted and the user is
2543 required to enter the firmware's menu to enable and activate the TPM
.
2544 If the TPM is left disabled and
/or deactivated most TPM commands will fail
.
2546 To create a passthrough TPM use the following two options
:
2548 -tpmdev passthrough
,id
=tpm0
-device tpm
-tis
,tpmdev
=tpm0
2550 Note that the @code
{-tpmdev
} id is @code
{tpm0
} and is referenced by
2551 @code
{tpmdev
=tpm0
} in the device option
.
2561 DEFHEADING(Linux
/Multiboot boot specific
:)
2564 When
using these options
, you can use a given Linux or Multiboot
2565 kernel without installing it
in the disk image
. It can be useful
2566 for easier testing of various kernels
.
2571 DEF("kernel", HAS_ARG
, QEMU_OPTION_kernel
, \
2572 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL
)
2574 @item
-kernel @
var{bzImage
}
2576 Use @
var{bzImage
} as kernel image
. The kernel can be either a Linux kernel
2577 or
in multiboot format
.
2580 DEF("append", HAS_ARG
, QEMU_OPTION_append
, \
2581 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL
)
2583 @item
-append @
var{cmdline
}
2585 Use @
var{cmdline
} as kernel command line
2588 DEF("initrd", HAS_ARG
, QEMU_OPTION_initrd
, \
2589 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL
)
2591 @item
-initrd @
var{file
}
2593 Use @
var{file
} as initial ram disk
.
2595 @item
-initrd
"@var{file1} arg=foo,@var{file2}"
2597 This syntax is only available with multiboot
.
2599 Use @
var{file1
} and @
var{file2
} as modules and pass arg
=foo as parameter to the
2603 DEF("dtb", HAS_ARG
, QEMU_OPTION_dtb
, \
2604 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL
)
2606 @item
-dtb @
var{file
}
2608 Use @
var{file
} as a device tree
binary (dtb
) image and pass it to the kernel
2617 DEFHEADING(Debug
/Expert options
:)
2622 DEF("serial", HAS_ARG
, QEMU_OPTION_serial
, \
2623 "-serial dev redirect the serial port to char device 'dev'\n",
2626 @item
-serial @
var{dev
}
2628 Redirect the virtual serial port to host character device
2629 @
var{dev
}. The
default device is @code
{vc
} in graphical mode and
2630 @code
{stdio
} in non graphical mode
.
2632 This option can be used several times to simulate up to
4 serial
2635 Use @code
{-serial none
} to disable all serial ports
.
2637 Available character devices are
:
2639 @item vc
[:@
var{W
}x@
var{H
}]
2640 Virtual console
. Optionally
, a width and height can be given
in pixel with
2644 It is also possible to specify width or height
in characters
:
2649 [Linux only
] Pseudo
TTY (a
new PTY is automatically allocated
)
2651 No device is allocated
.
2654 @item chardev
:@
var{id
}
2655 Use a named character device defined with the @code
{-chardev
} option
.
2657 [Linux only
] Use host tty
, e
.g
. @file
{/dev
/ttyS0
}. The host serial port
2658 parameters are set according to the emulated ones
.
2659 @item
/dev
/parport@
var{N
}
2660 [Linux only
, parallel port only
] Use host parallel port
2661 @
var{N
}. Currently SPP and EPP parallel port features can be used
.
2662 @item file
:@
var{filename
}
2663 Write output to @
var{filename
}. No character can be read
.
2665 [Unix only
] standard input
/output
2666 @item pipe
:@
var{filename
}
2667 name pipe @
var{filename
}
2669 [Windows only
] Use host serial port @
var{n
}
2670 @item udp
:[@
var{remote_host
}]:@
var{remote_port
}[@@
[@
var{src_ip
}]:@
var{src_port
}]
2671 This
implements UDP Net Console
.
2672 When @
var{remote_host
} or @
var{src_ip
} are not specified
2673 they
default to @code
{0.0.0.0}.
2674 When not
using a specified @
var{src_port
} a random port is automatically chosen
.
2676 If you just want a simple readonly console you can use @code
{netcat
} or
2677 @code
{nc
}, by starting QEMU with
: @code
{-serial udp
::4555} and nc as
:
2678 @code
{nc
-u
-l
-p
4555}. Any time QEMU writes something to that port it
2679 will appear
in the netconsole session
.
2681 If you plan to send characters back via netconsole or you want to stop
2682 and start QEMU a lot of times
, you should have QEMU use the same
2683 source port each time by
using something like @code
{-serial
2684 udp
::4555@@
:4556} to QEMU
. Another approach is to use a patched
2685 version of netcat which can listen to a TCP port and send and receive
2686 characters via udp
. If you have a patched version of netcat which
2687 activates telnet remote echo and single char transfer
, then you can
2688 use the following options to step up a netcat redirector to allow
2689 telnet on port
5555 to access the QEMU port
.
2692 -serial udp
::4555@@
:4556
2693 @item netcat options
:
2694 -u
-P
4555 -L
0.0.0.0:4556 -t
-p
5555 -I
-T
2695 @item telnet options
:
2699 @item tcp
:[@
var{host
}]:@
var{port
}[,@
var{server
}][,nowait
][,nodelay
][,reconnect
=@
var{seconds
}]
2700 The TCP Net Console has two modes of operation
. It can send the serial
2701 I
/O to a location or wait
for a connection from a location
. By
default
2702 the TCP Net Console is sent to @
var{host
} at the @
var{port
}. If you use
2703 the @
var{server
} option QEMU will wait
for a client socket application
2704 to connect to the port before continuing
, unless the @code
{nowait
}
2705 option was specified
. The @code
{nodelay
} option disables the Nagle buffering
2706 algorithm
. The @code
{reconnect
} option only applies
if @
var{noserver
} is
2707 set
, if the connection goes down it will attempt to reconnect at the
2708 given interval
. If @
var{host
} is omitted
, 0.0.0.0 is assumed
. Only
2709 one TCP connection at a time is accepted
. You can use @code
{telnet
} to
2710 connect to the corresponding character device
.
2712 @item Example to send tcp console to
192.168.0.2 port
4444
2713 -serial tcp
:192.168.0.2:4444
2714 @item Example to listen and wait on port
4444 for connection
2715 -serial tcp
::4444,server
2716 @item Example to not wait and listen on ip
192.168.0.100 port
4444
2717 -serial tcp
:192.168.0.100:4444,server
,nowait
2720 @item telnet
:@
var{host
}:@
var{port
}[,server
][,nowait
][,nodelay
]
2721 The telnet protocol is used instead of raw tcp sockets
. The options
2722 work the same as
if you had specified @code
{-serial tcp
}. The
2723 difference is that the port acts like a telnet server or client
using
2724 telnet option negotiation
. This will also allow you to send the
2725 MAGIC_SYSRQ sequence
if you use a telnet that supports sending the
break
2726 sequence
. Typically
in unix telnet you
do it with Control
-] and then
2727 type
"send break" followed by pressing the enter key
.
2729 @item unix
:@
var{path
}[,server
][,nowait
][,reconnect
=@
var{seconds
}]
2730 A unix domain socket is used instead of a tcp socket
. The option works the
2731 same as
if you had specified @code
{-serial tcp
} except the unix domain socket
2732 @
var{path
} is used
for connections
.
2734 @item mon
:@
var{dev_string
}
2735 This is a special option to allow the monitor to be multiplexed onto
2736 another serial port
. The monitor is accessed with key sequence of
2737 @key
{Control
-a
} and then pressing @key
{c
}.
2738 @
var{dev_string
} should be any one of the serial devices specified
2739 above
. An example to multiplex the monitor onto a telnet server
2740 listening on port
4444 would be
:
2742 @item
-serial mon
:telnet
::4444,server
,nowait
2744 When the monitor is multiplexed to stdio
in this way
, Ctrl
+C will not terminate
2745 QEMU any more but will be passed to the guest instead
.
2748 Braille device
. This will use BrlAPI to display the braille output on a real
2752 Three button serial mouse
. Configure the guest to use Microsoft protocol
.
2756 DEF("parallel", HAS_ARG
, QEMU_OPTION_parallel
, \
2757 "-parallel dev redirect the parallel port to char device 'dev'\n",
2760 @item
-parallel @
var{dev
}
2762 Redirect the virtual parallel port to host device @
var{dev
} (same
2763 devices as the serial port
). On Linux hosts
, @file
{/dev
/parportN
} can
2764 be used to use hardware devices connected on the corresponding host
2767 This option can be used several times to simulate up to
3 parallel
2770 Use @code
{-parallel none
} to disable all parallel ports
.
2773 DEF("monitor", HAS_ARG
, QEMU_OPTION_monitor
, \
2774 "-monitor dev redirect the monitor to char device 'dev'\n",
2777 @item
-monitor @
var{dev
}
2779 Redirect the monitor to host device @
var{dev
} (same devices as the
2781 The
default device is @code
{vc
} in graphical mode and @code
{stdio
} in
2783 Use @code
{-monitor none
} to disable the
default monitor
.
2785 DEF("qmp", HAS_ARG
, QEMU_OPTION_qmp
, \
2786 "-qmp dev like -monitor but opens in 'control' mode\n",
2789 @item
-qmp @
var{dev
}
2791 Like
-monitor but opens
in 'control' mode
.
2794 DEF("mon", HAS_ARG
, QEMU_OPTION_mon
, \
2795 "-mon [chardev=]name[,mode=readline|control][,default]\n", QEMU_ARCH_ALL
)
2797 @item
-mon
[chardev
=]name
[,mode
=readline|control
][,default]
2799 Setup monitor on chardev @
var{name
}.
2802 DEF("debugcon", HAS_ARG
, QEMU_OPTION_debugcon
, \
2803 "-debugcon dev redirect the debug console to char device 'dev'\n",
2806 @item
-debugcon @
var{dev
}
2808 Redirect the debug console to host device @
var{dev
} (same devices as the
2809 serial port
). The debug console is an I
/O port which is typically port
2810 0xe9; writing to that I
/O port sends output to
this device
.
2811 The
default device is @code
{vc
} in graphical mode and @code
{stdio
} in
2815 DEF("pidfile", HAS_ARG
, QEMU_OPTION_pidfile
, \
2816 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL
)
2818 @item
-pidfile @
var{file
}
2820 Store the QEMU process PID
in @
var{file
}. It is useful
if you launch QEMU
2824 DEF("singlestep", 0, QEMU_OPTION_singlestep
, \
2825 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL
)
2829 Run the emulation
in single step mode
.
2832 DEF("S", 0, QEMU_OPTION_S
, \
2833 "-S freeze CPU at startup (use 'c' to start execution)\n",
2838 Do not start CPU at
startup (you must type
'c' in the monitor
).
2841 DEF("realtime", HAS_ARG
, QEMU_OPTION_realtime
,
2842 "-realtime [mlock=on|off]\n"
2843 " run qemu with realtime features\n"
2844 " mlock=on|off controls mlock support (default: on)\n",
2847 @item
-realtime mlock
=on|off
2849 Run qemu with realtime features
.
2850 mlocking qemu and guest memory can be enabled via @option
{mlock
=on
}
2851 (enabled by
default).
2854 DEF("gdb", HAS_ARG
, QEMU_OPTION_gdb
, \
2855 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL
)
2857 @item
-gdb @
var{dev
}
2859 Wait
for gdb connection on device @
var{dev
} (@pxref
{gdb_usage
}). Typical
2860 connections will likely be TCP
-based
, but also UDP
, pseudo TTY
, or even
2861 stdio are reasonable use
case. The latter is allowing to start QEMU from
2862 within gdb and establish the connection via a pipe
:
2864 (gdb
) target remote | exec qemu
-system
-i386
-gdb stdio
...
2868 DEF("s", 0, QEMU_OPTION_s
, \
2869 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT
"\n",
2874 Shorthand
for -gdb tcp
::1234, i
.e
. open a gdbserver on TCP port
1234
2875 (@pxref
{gdb_usage
}).
2878 DEF("d", HAS_ARG
, QEMU_OPTION_d
, \
2879 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n",
2882 @item
-d @
var{item1
}[,...]
2884 Enable logging of specified items
. Use
'-d help' for a list of log items
.
2887 DEF("D", HAS_ARG
, QEMU_OPTION_D
, \
2888 "-D logfile output log to logfile (default stderr)\n",
2891 @item
-D @
var{logfile
}
2893 Output log
in @
var{logfile
} instead of to stderr
2896 DEF("L", HAS_ARG
, QEMU_OPTION_L
, \
2897 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
2902 Set the directory
for the BIOS
, VGA BIOS and keymaps
.
2905 DEF("bios", HAS_ARG
, QEMU_OPTION_bios
, \
2906 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL
)
2908 @item
-bios @
var{file
}
2910 Set the filename
for the BIOS
.
2913 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm
, \
2914 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL
)
2918 Enable KVM full virtualization support
. This option is only available
2919 if KVM support is enabled when compiling
.
2922 DEF("xen-domid", HAS_ARG
, QEMU_OPTION_xen_domid
,
2923 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL
)
2924 DEF("xen-create", 0, QEMU_OPTION_xen_create
,
2925 "-xen-create create domain using xen hypercalls, bypassing xend\n"
2926 " warning: should not be used when xend is in use\n",
2928 DEF("xen-attach", 0, QEMU_OPTION_xen_attach
,
2929 "-xen-attach attach to existing xen domain\n"
2930 " xend will use this when starting QEMU\n",
2933 @item
-xen
-domid @
var{id
}
2935 Specify xen guest domain @
var{id
} (XEN only
).
2938 Create domain
using xen hypercalls
, bypassing xend
.
2939 Warning
: should not be used when xend is
in use (XEN only
).
2942 Attach to existing xen domain
.
2943 xend will use
this when starting
QEMU (XEN only
).
2946 DEF("no-reboot", 0, QEMU_OPTION_no_reboot
, \
2947 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL
)
2951 Exit instead of rebooting
.
2954 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown
, \
2955 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL
)
2958 @findex
-no
-shutdown
2959 Don
't exit QEMU on guest shutdown, but instead only stop the emulation.
2960 This allows for instance switching to monitor to commit changes to the
2964 DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
2965 "-loadvm [tag|id]\n" \
2966 " start right away with a saved state (loadvm in monitor)\n",
2969 @item -loadvm @var{file}
2971 Start right away with a saved state (@code{loadvm} in monitor)
2975 DEF("daemonize", 0, QEMU_OPTION_daemonize, \
2976 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
2981 Daemonize the QEMU process after initialization. QEMU will not detach from
2982 standard IO until it is ready to receive connections on any of its devices.
2983 This option is a useful way for external programs to launch QEMU without having
2984 to cope with initialization race conditions.
2987 DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
2988 "-option-rom rom load a file, rom, into the option ROM space\n",
2991 @item -option-rom @var{file}
2993 Load the contents of @var{file} as an option ROM.
2994 This option is useful to load things like EtherBoot.
2997 HXCOMM Silently ignored for compatibility
2998 DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL)
3000 HXCOMM Options deprecated by -rtc
3001 DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
3002 DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
3004 DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
3005 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
3006 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
3011 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
3013 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
3014 UTC or local time, respectively. @code{localtime} is required for correct date in
3015 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
3016 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
3018 By default the RTC is driven by the host system time. This allows using of the
3019 RTC as accurate reference clock inside the guest, specifically if the host
3020 time is smoothly following an accurate external reference clock, e.g. via NTP.
3021 If you want to isolate the guest time from the host, you can set @option{clock}
3022 to @code{rt} instead. To even prevent it from progressing during suspension,
3023 you can set it to @code{vm}.
3025 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
3026 specifically with Windows' ACPI HAL
. This option will
try to figure out how
3027 many timer interrupts were not processed by the Windows guest and will
3031 DEF("icount", HAS_ARG
, QEMU_OPTION_icount
, \
3032 "-icount [shift=N|auto][,align=on|off]\n" \
3033 " enable virtual instruction counter with 2^N clock ticks per\n" \
3034 " instruction and enable aligning the host and virtual clocks\n", QEMU_ARCH_ALL
)
3036 @item
-icount
[shift
=@
var{N
}|auto
]
3038 Enable virtual instruction counter
. The virtual cpu will execute one
3039 instruction every
2^@
var{N
} ns of virtual time
. If @code
{auto
} is specified
3040 then the virtual cpu speed will be automatically adjusted to keep virtual
3041 time within a few seconds of real time
.
3043 Note that
while this option can give deterministic behavior
, it does not
3044 provide cycle accurate emulation
. Modern CPUs contain superscalar out of
3045 order cores with complex cache hierarchies
. The number of instructions
3046 executed often has little or no correlation with actual performance
.
3048 @option
{align
=on
} will activate the delay algorithm which will
try to
3049 to synchronise the host clock and the virtual clock
. The goal is to
3050 have a guest running at the real frequency imposed by the shift option
.
3051 Whenever the guest clock is behind the host clock and
if
3052 @option
{align
=on
} is specified then we print a messsage to the user
3053 to inform about the delay
.
3054 Currently
this option does not work when @option
{shift
} is @code
{auto
}.
3055 Note
: The sync algorithm will work
for those shift values
for which
3056 the guest clock runs ahead of the host clock
. Typically
this happens
3057 when the shift value is
high (how high depends on the host machine
).
3060 DEF("watchdog", HAS_ARG
, QEMU_OPTION_watchdog
, \
3061 "-watchdog i6300esb|ib700\n" \
3062 " enable virtual hardware watchdog [default=none]\n",
3065 @item
-watchdog @
var{model
}
3067 Create a virtual hardware watchdog device
. Once
enabled (by a guest
3068 action
), the watchdog must be periodically polled by an agent inside
3069 the guest or
else the guest will be restarted
.
3071 The @
var{model
} is the model of hardware watchdog to emulate
. Choices
3072 for model are
: @code
{ib700
} (iBASE
700) which is a very simple ISA
3073 watchdog with a single timer
, or @code
{i6300esb
} (Intel
6300ESB I
/O
3074 controller hub
) which is a much more featureful PCI
-based dual
-timer
3075 watchdog
. Choose a model
for which your guest has drivers
.
3077 Use @code
{-watchdog help
} to list available hardware models
. Only one
3078 watchdog can be enabled
for a guest
.
3081 DEF("watchdog-action", HAS_ARG
, QEMU_OPTION_watchdog_action
, \
3082 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
3083 " action when watchdog fires [default=reset]\n",
3086 @item
-watchdog
-action @
var{action
}
3087 @findex
-watchdog
-action
3089 The @
var{action
} controls what QEMU will
do when the watchdog timer
3092 @code
{reset
} (forcefully reset the guest
).
3093 Other possible actions are
:
3094 @code
{shutdown
} (attempt to gracefully shutdown the guest
),
3095 @code
{poweroff
} (forcefully poweroff the guest
),
3096 @code
{pause
} (pause the guest
),
3097 @code
{debug
} (print a debug message and
continue), or
3098 @code
{none
} (do nothing
).
3100 Note that the @code
{shutdown
} action requires that the guest responds
3101 to ACPI signals
, which it may not be able to
do in the sort of
3102 situations where the watchdog would have expired
, and thus
3103 @code
{-watchdog
-action shutdown
} is not recommended
for production use
.
3108 @item
-watchdog i6300esb
-watchdog
-action pause
3109 @item
-watchdog ib700
3113 DEF("echr", HAS_ARG
, QEMU_OPTION_echr
, \
3114 "-echr chr set terminal escape character instead of ctrl-a\n",
3118 @item
-echr @
var{numeric_ascii_value
}
3120 Change the escape character used
for switching to the monitor when
using
3121 monitor and serial sharing
. The
default is @code
{0x01} when
using the
3122 @code
{-nographic
} option
. @code
{0x01} is equal to pressing
3123 @code
{Control
-a
}. You can select a different character from the ascii
3124 control keys where
1 through
26 map to Control
-a through Control
-z
. For
3125 instance you could use the either of the following to change the escape
3126 character to Control
-t
.
3133 DEF("virtioconsole", HAS_ARG
, QEMU_OPTION_virtiocon
, \
3134 "-virtioconsole c\n" \
3135 " set virtio console\n", QEMU_ARCH_ALL
)
3137 @item
-virtioconsole @
var{c
}
3138 @findex
-virtioconsole
3141 This option is maintained
for backward compatibility
.
3143 Please use @code
{-device virtconsole
} for the
new way of invocation
.
3146 DEF("show-cursor", 0, QEMU_OPTION_show_cursor
, \
3147 "-show-cursor show cursor\n", QEMU_ARCH_ALL
)
3150 @findex
-show
-cursor
3154 DEF("tb-size", HAS_ARG
, QEMU_OPTION_tb_size
, \
3155 "-tb-size n set TB size\n", QEMU_ARCH_ALL
)
3157 @item
-tb
-size @
var{n
}
3162 DEF("incoming", HAS_ARG
, QEMU_OPTION_incoming
, \
3163 "-incoming p prepare for incoming migration, listen on port p\n",
3166 @item
-incoming @
var{port
}
3168 Prepare
for incoming migration
, listen on @
var{port
}.
3171 DEF("nodefaults", 0, QEMU_OPTION_nodefaults
, \
3172 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL
)
3176 Don
't create default devices. Normally, QEMU sets the default devices like serial
3177 port, parallel port, virtual console, monitor device, VGA adapter, floppy and
3178 CD-ROM drive and others. The @code{-nodefaults} option will disable all those
3183 DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
3184 "-chroot dir chroot to dir just before starting the VM\n",
3188 @item -chroot @var{dir}
3190 Immediately before starting guest execution, chroot to the specified
3191 directory. Especially useful in combination with -runas.
3195 DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
3196 "-runas user change to user id user just before starting the VM\n",
3200 @item -runas @var{user}
3202 Immediately before starting guest execution, drop root privileges, switching
3203 to the specified user.
3206 DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
3207 "-prom-env variable=value\n"
3208 " set OpenBIOS nvram variables\n",
3209 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3211 @item -prom-env @var{variable}=@var{value}
3213 Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
3215 DEF("semihosting", 0, QEMU_OPTION_semihosting,
3216 "-semihosting semihosting mode\n",
3217 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32)
3220 @findex -semihosting
3221 Semihosting mode (ARM, M68K, Xtensa only).
3223 DEF("old-param", 0, QEMU_OPTION_old_param,
3224 "-old-param old param mode\n", QEMU_ARCH_ARM)
3227 @findex -old-param (ARM)
3228 Old param mode (ARM only).
3231 DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
3232 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off
').\n",
3235 @item -sandbox @var{arg}
3237 Enable Seccomp mode 2 system call filter. 'on
' will enable syscall filtering and 'off
' will
3238 disable it. The default is 'off
'.
3241 DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
3242 "-readconfig <file>\n", QEMU_ARCH_ALL)
3244 @item -readconfig @var{file}
3246 Read device configuration from @var{file}. This approach is useful when you want to spawn
3247 QEMU process with many command line options but you don't want to exceed the command line
3250 DEF("writeconfig", HAS_ARG
, QEMU_OPTION_writeconfig
,
3251 "-writeconfig <file>\n"
3252 " read/write config file\n", QEMU_ARCH_ALL
)
3254 @item
-writeconfig @
var{file
}
3255 @findex
-writeconfig
3256 Write device configuration to @
var{file
}. The @
var{file
} can be either filename to save
3257 command line and device configuration into file or dash @code
{-}) character to print the
3258 output to stdout
. This can be later used as input file
for @code
{-readconfig
} option
.
3260 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig
,
3262 " do not load default config files at startup\n",
3266 @findex
-nodefconfig
3267 Normally QEMU loads configuration files from @
var{sysconfdir
} and @
var{datadir
} at startup
.
3268 The @code
{-nodefconfig
} option will prevent QEMU from loading any of those config files
.
3270 DEF("no-user-config", 0, QEMU_OPTION_nouserconfig
,
3272 " do not load user-provided config files at startup\n",
3275 @item
-no
-user
-config
3276 @findex
-no
-user
-config
3277 The @code
{-no
-user
-config
} option makes QEMU not load any of the user
-provided
3278 config files on @
var{sysconfdir
}, but won
't make it skip the QEMU-provided config
3279 files from @var{datadir}.
3281 DEF("trace", HAS_ARG, QEMU_OPTION_trace,
3282 "-trace [events=<file>][,file=<file>]\n"
3283 " specify tracing options\n",
3286 HXCOMM This line is not accurate, as some sub-options are backend-specific but
3287 HXCOMM HX does not support conditional compilation of text.
3288 @item -trace [events=@var{file}][,file=@var{file}]
3291 Specify tracing options.
3294 @item events=@var{file}
3295 Immediately enable events listed in @var{file}.
3296 The file must contain one event name (as listed in the @var{trace-events} file)
3298 This option is only available if QEMU has been compiled with
3299 either @var{simple} or @var{stderr} tracing backend.
3300 @item file=@var{file}
3301 Log output traces to @var{file}.
3303 This option is only available if QEMU has been compiled with
3304 the @var{simple} tracing backend.
3309 DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL)
3310 DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL)
3313 DEF("enable-fips", 0, QEMU_OPTION_enablefips,
3314 "-enable-fips enable FIPS 140-2 compliance\n",
3319 @findex -enable-fips
3320 Enable FIPS 140-2 compliance mode.
3323 HXCOMM Deprecated by -machine accel=tcg property
3324 DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386)
3326 HXCOMM Deprecated by kvm-pit driver properties
3327 DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection,
3330 HXCOMM Deprecated (ignored)
3331 DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386)
3333 HXCOMM Deprecated by -machine kernel_irqchip=on|off property
3334 DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386)
3336 HXCOMM Deprecated (ignored)
3337 DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL)
3339 DEF("object", HAS_ARG, QEMU_OPTION_object,
3340 "-object TYPENAME[,PROP1=VALUE1,...]\n"
3341 " create an new object of type TYPENAME setting properties\n"
3342 " in the order they are specified. Note that the 'id
'\n"
3343 " property must be set. These objects are placed in the\n"
3344 " '/objects
' path.\n",
3347 @item -object @var{typename}[,@var{prop1}=@var{value1},...]
3349 Create an new object of type @var{typename} setting properties
3350 in the order they are specified. Note that the 'id
'
3351 property must be set. These objects are placed in the
3355 DEF("msg", HAS_ARG, QEMU_OPTION_msg,
3356 "-msg timestamp[=on|off]\n"
3357 " change the format of messages\n"
3358 " on|off controls leading timestamps (default:on)\n",
3361 @item -msg timestamp[=on|off]
3363 prepend a timestamp to each log message.(default:on)
3366 DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate,
3367 "-dump-vmstate <file>\n"
3368 " Output vmstate information in JSON format to file.\n"
3369 " Use the scripts/vmstate-static-checker.py file to\n"
3370 " check for possible regressions in migration code\n"
3371 " by comparing two such vmstate dumps.",
3374 @item -dump-vmstate @var{file}
3375 @findex -dump-vmstate
3376 Dump json-encoded vmstate information for current machine type to file
3380 HXCOMM This is the last statement. Insert new options before this line!