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, hax, hvf, whpx or tcg (default: tcg)\n"
35 " kernel_irqchip=on|off|split controls accelerated irqchip support (default=off)\n"
36 " vmport=on|off|auto controls emulation of vmport (default: auto)\n"
37 " kvm_shadow_mem=size of KVM shadow MMU in bytes\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 " igd-passthru=on|off controls IGD GFX passthrough support (default=off)\n"
41 " aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n"
42 " dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n"
43 " suppress-vmdesc=on|off disables self-describing migration (default=off)\n"
44 " nvdimm=on|off controls NVDIMM support (default=off)\n"
45 " enforce-config-section=on|off enforce configuration section migration (default=off)\n"
46 " s390-squash-mcss=on|off (deprecated) controls support for squashing into default css (default=off)\n"
47 " memory-encryption=@var{} memory encryption object to use (default=none)\n",
50 @item
-machine
[type
=]@
var{name
}[,prop
=@
var{value
}[,...]]
52 Select the emulated machine by @
var{name
}. Use @code
{-machine help
} to list
55 For architectures which aim to support live migration compatibility
56 across releases
, each release will introduce a
new versioned machine
57 type
. For example
, the
2.8.0 release introduced machine types
58 ``pc
-i440fx
-2.8'' and ``pc
-q35
-2.8'' for the x86_64
/i686 architectures
.
60 To allow live migration of guests from QEMU version
2.8.0, to QEMU
61 version
2.9.0, the
2.9.0 version must support the ``pc
-i440fx
-2.8''
62 and ``pc
-q35
-2.8'' machines too
. To allow users live migrating VMs
63 to skip multiple intermediate releases when upgrading
, new releases
64 of QEMU will support machine types from many previous versions
.
66 Supported machine properties are
:
68 @item accel
=@
var{accels1
}[:@
var{accels2
}[:...]]
69 This is used to enable an accelerator
. Depending on the target architecture
,
70 kvm
, xen
, hax
, hvf
, whpx or tcg can be available
. By
default, tcg is used
. If there is
71 more than one accelerator specified
, the next one is used
if the previous one
73 @item kernel_irqchip
=on|off
74 Controls
in-kernel irqchip support
for the chosen accelerator when available
.
75 @item gfx_passthru
=on|off
76 Enables IGD GFX passthrough support
for the chosen machine when available
.
77 @item vmport
=on|off|auto
78 Enables emulation of VMWare IO port
, for vmmouse etc
. auto says to select the
79 value based on accel
. For accel
=xen the
default is off otherwise the
default
81 @item kvm_shadow_mem
=size
82 Defines the size of the KVM shadow MMU
.
83 @item dump
-guest
-core
=on|off
84 Include guest memory
in a core dump
. The
default is on
.
85 @item mem
-merge
=on|off
86 Enables or disables memory merge support
. This feature
, when supported by
87 the host
, de
-duplicates identical memory pages among VMs instances
89 @item aes
-key
-wrap
=on|off
90 Enables or disables AES key wrapping support on s390
-ccw hosts
. This feature
91 controls whether AES wrapping keys will be created to allow
92 execution of AES cryptographic functions
. The
default is on
.
93 @item dea
-key
-wrap
=on|off
94 Enables or disables DEA key wrapping support on s390
-ccw hosts
. This feature
95 controls whether DEA wrapping keys will be created to allow
96 execution of DEA cryptographic functions
. The
default is on
.
98 Enables or disables NVDIMM support
. The
default is off
.
99 @item s390
-squash
-mcss
=on|off
100 Enables or disables squashing subchannels into the
default css
.
102 NOTE
: This property is deprecated and will be removed
in future releases
.
103 The ``s390
-squash
-mcss
=on`` property has been obsoleted by allowing the
104 cssid to be chosen freely
. Instead of squashing subchannels into the
105 default channel subsystem image
for guests that
do not support multiple
106 channel subsystems
, all devices can be put into the
default channel
108 @item enforce
-config
-section
=on|off
109 If @option
{enforce
-config
-section
} is set to @
var{on
}, force migration
110 code to send configuration section even
if the machine
-type sets the
111 @option
{migration
.send
-configuration
} property to @
var{off
}.
112 NOTE
: this parameter is deprecated
. Please use @option
{-global
}
113 @option
{migration
.send
-configuration
}=@
var{on|off
} instead
.
114 @item memory
-encryption
=@
var{}
115 Memory encryption object to use
. The
default is none
.
119 HXCOMM Deprecated by
-machine
120 DEF("M", HAS_ARG
, QEMU_OPTION_M
, "", QEMU_ARCH_ALL
)
122 DEF("cpu", HAS_ARG
, QEMU_OPTION_cpu
,
123 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL
)
125 @item
-cpu @
var{model
}
127 Select CPU
model (@code
{-cpu help
} for list and additional feature selection
)
130 DEF("accel", HAS_ARG
, QEMU_OPTION_accel
,
131 "-accel [accel=]accelerator[,thread=single|multi]\n"
132 " select accelerator (kvm, xen, hax, hvf, whpx or tcg; use 'help' for a list)\n"
133 " thread=single|multi (enable multi-threaded TCG)\n", QEMU_ARCH_ALL
)
135 @item
-accel @
var{name
}[,prop
=@
var{value
}[,...]]
137 This is used to enable an accelerator
. Depending on the target architecture
,
138 kvm
, xen
, hax
, hvf
, whpx or tcg can be available
. By
default, tcg is used
. If there is
139 more than one accelerator specified
, the next one is used
if the previous one
142 @item thread
=single|multi
143 Controls number of TCG threads
. When the TCG is multi
-threaded there will be one
144 thread per vCPU therefor taking advantage of additional host cores
. The
default
145 is to enable multi
-threading where both the back
-end and front
-ends support it and
146 no incompatible TCG features have been
enabled (e
.g
. icount
/replay
).
150 DEF("smp", HAS_ARG
, QEMU_OPTION_smp
,
151 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
152 " set the number of CPUs to 'n' [default=1]\n"
153 " maxcpus= maximum number of total cpus, including\n"
154 " offline CPUs for hotplug, etc\n"
155 " cores= number of CPU cores on one socket\n"
156 " threads= number of threads on one CPU core\n"
157 " sockets= number of discrete sockets in the system\n",
160 @item
-smp
[cpus
=]@
var{n
}[,cores
=@
var{cores
}][,threads
=@
var{threads
}][,sockets
=@
var{sockets
}][,maxcpus
=@
var{maxcpus
}]
162 Simulate an SMP system with @
var{n
} CPUs
. On the PC target
, up to
255
163 CPUs are supported
. On Sparc32 target
, Linux limits the number of usable CPUs
165 For the PC target
, the number of @
var{cores
} per socket
, the number
166 of @
var{threads
} per cores and the total number of @
var{sockets
} can be
167 specified
. Missing values will be computed
. If any on the three values is
168 given
, the total number of CPUs @
var{n
} can be omitted
. @
var{maxcpus
}
169 specifies the maximum number of hotpluggable CPUs
.
172 DEF("numa", HAS_ARG
, QEMU_OPTION_numa
,
173 "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
174 "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
175 "-numa dist,src=source,dst=destination,val=distance\n"
176 "-numa cpu,node-id=node[,socket-id=x][,core-id=y][,thread-id=z]\n",
179 @item
-numa node
[,mem
=@
var{size
}][,cpus
=@
var{firstcpu
}[-@
var{lastcpu
}]][,nodeid
=@
var{node
}]
180 @itemx
-numa node
[,memdev
=@
var{id
}][,cpus
=@
var{firstcpu
}[-@
var{lastcpu
}]][,nodeid
=@
var{node
}]
181 @itemx
-numa dist
,src
=@
var{source
},dst
=@
var{destination
},val
=@
var{distance
}
182 @itemx
-numa cpu
,node
-id
=@
var{node
}[,socket
-id
=@
var{x
}][,core
-id
=@
var{y
}][,thread
-id
=@
var{z
}]
184 Define a NUMA node and assign RAM and VCPUs to it
.
185 Set the NUMA distance from a source node to a destination node
.
187 Legacy VCPU assignment uses @samp
{cpus
} option where
188 @
var{firstcpu
} and @
var{lastcpu
} are CPU indexes
. Each
189 @samp
{cpus
} option represent a contiguous range of CPU indexes
190 (or a single VCPU
if @
var{lastcpu
} is omitted
). A non
-contiguous
191 set of VCPUs can be represented by providing multiple @samp
{cpus
}
192 options
. If @samp
{cpus
} is omitted on all nodes
, VCPUs are automatically
195 For example
, the following option assigns VCPUs
0, 1, 2 and
5 to
198 -numa node
,cpus
=0-2,cpus
=5
201 @samp
{cpu
} option is a
new alternative to @samp
{cpus
} option
202 which uses @samp
{socket
-id|core
-id|thread
-id
} properties to assign
203 CPU objects to a @
var{node
} using topology layout properties of CPU
.
204 The set of properties is machine specific
, and depends on used
205 machine type
/@samp
{smp
} options
. It could be queried with
206 @samp
{hotpluggable
-cpus
} monitor command
.
207 @samp
{node
-id
} property specifies @
var{node
} to which CPU object
208 will be assigned
, it
's required for @var{node} to be declared
209 with @samp{node} option before it's used with @samp
{cpu
} option
.
214 -smp
1,sockets
=2,maxcpus
=2 \
215 -numa node
,nodeid
=0 -numa node
,nodeid
=1 \
216 -numa cpu
,node
-id
=0,socket
-id
=0 -numa cpu
,node
-id
=1,socket
-id
=1
219 @samp
{mem
} assigns a given RAM amount to a node
. @samp
{memdev
}
220 assigns RAM from a given memory backend device to a node
. If
221 @samp
{mem
} and @samp
{memdev
} are omitted
in all nodes
, RAM is
222 split equally between them
.
224 @samp
{mem
} and @samp
{memdev
} are mutually exclusive
. Furthermore
,
225 if one node uses @samp
{memdev
}, all of them have to use it
.
227 @
var{source
} and @
var{destination
} are NUMA node IDs
.
228 @
var{distance
} is the NUMA distance from @
var{source
} to @
var{destination
}.
229 The distance from a node to itself is always
10. If any pair of nodes is
230 given a distance
, then all pairs must be given distances
. Although
, when
231 distances are only given
in one direction
for each pair of nodes
, then
232 the distances
in the opposite directions are assumed to be the same
. If
,
233 however
, an asymmetrical pair of distances is given
for even one node
234 pair
, then all node pairs must be provided distance values
for both
235 directions
, even when they are symmetrical
. When a node is unreachable
236 from another node
, set the pair
's distance to 255.
238 Note that the -@option{numa} option doesn't allocate any of the
239 specified resources
, it just assigns existing resources to NUMA
240 nodes
. This means that one still has to use the @option
{-m
},
241 @option
{-smp
} options to allocate RAM and VCPUs respectively
.
245 DEF("add-fd", HAS_ARG
, QEMU_OPTION_add_fd
,
246 "-add-fd fd=fd,set=set[,opaque=opaque]\n"
247 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL
)
249 @item
-add
-fd fd
=@
var{fd
},set
=@
var{set
}[,opaque
=@
var{opaque
}]
252 Add a file descriptor to an fd set
. Valid options are
:
256 This option defines the file descriptor of which a duplicate is added to fd set
.
257 The file descriptor cannot be stdin
, stdout
, or stderr
.
259 This option defines the ID of the fd set to add the file descriptor to
.
260 @item opaque
=@
var{opaque
}
261 This option defines a free
-form string that can be used to describe @
var{fd
}.
264 You can open an image
using pre
-opened file descriptors from an fd set
:
267 -add
-fd fd
=3,set
=2,opaque
="rdwr:/path/to/file"
268 -add
-fd fd
=4,set
=2,opaque
="rdonly:/path/to/file"
269 -drive file
=/dev
/fdset
/2,index
=0,media
=disk
273 DEF("set", HAS_ARG
, QEMU_OPTION_set
,
274 "-set group.id.arg=value\n"
275 " set <arg> parameter for item <id> of type <group>\n"
276 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL
)
278 @item
-set @
var{group
}.@
var{id
}.@
var{arg
}=@
var{value
}
280 Set parameter @
var{arg
} for item @
var{id
} of type @
var{group
}
283 DEF("global", HAS_ARG
, QEMU_OPTION_global
,
284 "-global driver.property=value\n"
285 "-global driver=driver,property=property,value=value\n"
286 " set a global default for a driver property\n",
289 @item
-global @
var{driver
}.@
var{prop
}=@
var{value
}
290 @itemx
-global driver
=@
var{driver
},property
=@
var{property
},value
=@
var{value
}
292 Set
default value of @
var{driver
}'s property @var{prop} to @var{value}, e.g.:
295 qemu-system-i386 -global ide-hd.physical_block_size=4096 disk-image.img
298 In particular, you can use this to set driver properties for devices which are
299 created automatically by the machine model. To create a device which is not
300 created automatically and set properties on it, use -@option{device}.
302 -global @var{driver}.@var{prop}=@var{value} is shorthand for -global
303 driver=@var{driver},property=@var{prop},value=@var{value}. The
304 longhand syntax works even when @var{driver} contains a dot.
307 DEF("boot", HAS_ARG, QEMU_OPTION_boot,
308 "-boot [order=drives][,once=drives][,menu=on|off]\n"
309 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
310 " 'drives
': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
311 " 'sp_name
': the file's name that would be passed to bios as logo picture
, if menu
=on
\n"
312 " 'sp_time': the period that splash picture last
if menu
=on
, unit is ms
\n"
313 " 'rb_timeout': the timeout before guest reboot when boot failed
, unit is ms
\n",
316 @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]
318 Specify boot order @var{drives} as a string of drive letters. Valid
319 drive letters depend on the target architecture. The x86 PC uses: a, b
320 (floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
321 from network adapter 1-4), hard disk boot is the default. To apply a
322 particular boot order only on the first startup, specify it via
323 @option{once}. Note that the @option{order} or @option{once} parameter
324 should not be used together with the @option{bootindex} property of
325 devices, since the firmware implementations normally do not support both
328 Interactive boot menus/prompts can be enabled via @option{menu=on} as far
329 as firmware/BIOS supports them. The default is non-interactive boot.
331 A splash picture could be passed to bios, enabling user to show it as logo,
332 when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
333 supports them. Currently Seabios for X86 system support it.
334 limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
335 format(true color). The resolution should be supported by the SVGA mode, so
336 the recommended is 320x240, 640x480, 800x640.
338 A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms
339 when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not
340 reboot, qemu passes '-1' to bios by default. Currently Seabios for X86
343 Do strict boot via @option{strict=on} as far as firmware/BIOS
344 supports it. This only effects when boot priority is changed by
345 bootindex options. The default is non-strict boot.
348 # try to boot from network first, then from hard disk
349 qemu-system-i386 -boot order=nc
350 # boot from CD-ROM first, switch back to default order after reboot
351 qemu-system-i386 -boot once=d
352 # boot with a splash picture for 5 seconds.
353 qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
356 Note: The legacy format '-boot @var{drives}' is still supported but its
357 use is discouraged as it may be removed from future versions.
360 DEF("m
", HAS_ARG, QEMU_OPTION_m,
361 "-m
[size
=]megs
[,slots
=n
,maxmem
=size
]\n"
362 " configure guest RAM
\n"
363 " size
: initial amount of guest memory
\n"
364 " slots
: number of hotplug
slots (default: none
)\n"
365 " maxmem
: maximum amount of guest
memory (default: none
)\n"
366 "NOTE
: Some architectures might enforce a specific granularity
\n",
369 @item -m [size=]@var{megs}[,slots=n,maxmem=size]
371 Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB.
372 Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in
373 megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem}
374 could be used to set amount of hotpluggable memory slots and maximum amount of
375 memory. Note that @var{maxmem} must be aligned to the page size.
377 For example, the following command-line sets the guest startup RAM size to
378 1GB, creates 3 slots to hotplug additional memory and sets the maximum
379 memory the guest can reach to 4GB:
382 qemu-system-x86_64 -m 1G,slots=3,maxmem=4G
385 If @var{slots} and @var{maxmem} are not specified, memory hotplug won't
386 be enabled and the guest startup RAM will never increase.
389 DEF("mem
-path
", HAS_ARG, QEMU_OPTION_mempath,
390 "-mem
-path FILE provide backing storage
for guest RAM
\n", QEMU_ARCH_ALL)
392 @item -mem-path @var{path}
394 Allocate guest RAM from a temporarily created file in @var{path}.
397 DEF("mem
-prealloc
", 0, QEMU_OPTION_mem_prealloc,
398 "-mem
-prealloc preallocate guest
memory (use with
-mem
-path
)\n",
402 @findex -mem-prealloc
403 Preallocate memory when using -mem-path.
406 DEF("k
", HAS_ARG, QEMU_OPTION_k,
407 "-k language use keyboard
layout (for example
'fr' for French
)\n",
410 @item -k @var{language}
412 Use keyboard layout @var{language} (for example @code{fr} for
413 French). This option is only needed where it is not easy to get raw PC
414 keycodes (e.g. on Macs, with some X11 servers or with a VNC or curses
415 display). You don't normally need to use it on PC/Linux or PC/Windows
418 The available layouts are:
420 ar de-ch es fo fr-ca hu ja mk no pt-br sv
421 da en-gb et fr fr-ch is lt nl pl ru th
422 de en-us fi fr-be hr it lv nl-be pt sl tr
425 The default is @code{en-us}.
429 DEF("audio
-help
", 0, QEMU_OPTION_audio_help,
430 "-audio
-help print list of audio drivers and their options
\n",
435 Will show the audio subsystem help: list of drivers, tunable
439 DEF("soundhw
", HAS_ARG, QEMU_OPTION_soundhw,
440 "-soundhw c1
,... enable audio support
\n"
441 " and only specified sound
cards (comma separated list
)\n"
442 " use
'-soundhw help' to get the list of supported cards
\n"
443 " use
'-soundhw all' to enable all of them
\n", QEMU_ARCH_ALL)
445 @item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
447 Enable audio and selected sound hardware. Use 'help' to print all
448 available sound hardware.
451 qemu-system-i386 -soundhw sb16,adlib disk.img
452 qemu-system-i386 -soundhw es1370 disk.img
453 qemu-system-i386 -soundhw ac97 disk.img
454 qemu-system-i386 -soundhw hda disk.img
455 qemu-system-i386 -soundhw all disk.img
456 qemu-system-i386 -soundhw help
459 Note that Linux's i810_audio OSS kernel (for AC97) module might
460 require manually specifying clocking.
463 modprobe i810_audio clocking=48000
467 DEF("balloon
", HAS_ARG, QEMU_OPTION_balloon,
468 "-balloon virtio
[,addr
=str
]\n"
469 " enable virtio balloon
device (deprecated
)\n", QEMU_ARCH_ALL)
471 @item -balloon virtio[,addr=@var{addr}]
473 Enable virtio balloon device, optionally with PCI address @var{addr}. This
474 option is deprecated, use @option{-device virtio-balloon} instead.
477 DEF("device
", HAS_ARG, QEMU_OPTION_device,
478 "-device driver
[,prop
[=value
][,...]]\n"
479 " add
device (based on driver
)\n"
480 " prop
=value
,... sets driver properties
\n"
481 " use
'-device help' to print all possible drivers
\n"
482 " use
'-device driver,help' to print all possible properties
\n",
485 @item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
487 Add device @var{driver}. @var{prop}=@var{value} sets driver
488 properties. Valid properties depend on the driver. To get help on
489 possible drivers and properties, use @code{-device help} and
490 @code{-device @var{driver},help}.
493 @item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}][,sdrfile=@var{file}][,furareasize=@var{val}][,furdatafile=@var{file}]
495 Add an IPMI BMC. This is a simulation of a hardware management
496 interface processor that normally sits on a system. It provides
497 a watchdog and the ability to reset and power control the system.
498 You need to connect this to an IPMI interface to make it useful
500 The IPMI slave address to use for the BMC. The default is 0x20.
501 This address is the BMC's address on the I2C network of management
502 controllers. If you don't know what this means, it is safe to ignore
507 The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
508 @item slave_addr=@var{val}
509 Define slave address to use for the BMC. The default is 0x20.
510 @item sdrfile=@var{file}
511 file containing raw Sensor Data Records (SDR) data. The default is none.
512 @item fruareasize=@var{val}
513 size of a Field Replaceable Unit (FRU) area. The default is 1024.
514 @item frudatafile=@var{file}
515 file containing raw Field Replaceable Unit (FRU) inventory data. The default is none.
518 @item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}]
520 Add a connection to an external IPMI BMC simulator. Instead of
521 locally emulating the BMC like the above item, instead connect
522 to an external entity that provides the IPMI services.
524 A connection is made to an external BMC simulator. If you do this, it
525 is strongly recommended that you use the "reconnect
=" chardev option
526 to reconnect to the simulator if the connection is lost. Note that if
527 this is not used carefully, it can be a security issue, as the
528 interface has the ability to send resets, NMIs, and power off the VM.
529 It's best if QEMU makes a connection to an external simulator running
530 on a secure port on localhost, so neither the simulator nor QEMU is
531 exposed to any outside network.
533 See the "lanserv
/README
.vm
" file in the OpenIPMI library for more
534 details on the external interface.
536 @item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
538 Add a KCS IPMI interafce on the ISA bus. This also adds a
539 corresponding ACPI and SMBIOS entries, if appropriate.
543 The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
544 @item ioport=@var{val}
545 Define the I/O address of the interface. The default is 0xca0 for KCS.
547 Define the interrupt to use. The default is 5. To disable interrupts,
551 @item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
553 Like the KCS interface, but defines a BT interface. The default port is
554 0xe4 and the default interrupt is 5.
558 DEF("name
", HAS_ARG, QEMU_OPTION_name,
559 "-name string1
[,process
=string2
][,debug
-threads
=on|off
]\n"
560 " set the name of the guest
\n"
561 " string1 sets the window title and string2 the process
name (on Linux
)\n"
562 " When debug
-threads is enabled
, individual threads are given a separate
name (on Linux
)\n"
563 " NOTE
: The thread names are
for debugging and not a stable API
.\n",
566 @item -name @var{name}
568 Sets the @var{name} of the guest.
569 This name will be displayed in the SDL window caption.
570 The @var{name} will also be used for the VNC server.
571 Also optionally set the top visible process name in Linux.
572 Naming of individual threads can also be enabled on Linux to aid debugging.
575 DEF("uuid
", HAS_ARG, QEMU_OPTION_uuid,
576 "-uuid
%08x
-%04x
-%04x
-%04x
-%012x
\n"
577 " specify machine UUID
\n", QEMU_ARCH_ALL)
579 @item -uuid @var{uuid}
589 DEFHEADING(Block device options:)
594 DEF("fda
", HAS_ARG, QEMU_OPTION_fda,
595 "-fda
/-fdb file use
'file' as floppy disk
0/1 image
\n", QEMU_ARCH_ALL)
596 DEF("fdb
", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
598 @item -fda @var{file}
599 @itemx -fdb @var{file}
602 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}).
605 DEF("hda
", HAS_ARG, QEMU_OPTION_hda,
606 "-hda
/-hdb file use
'file' as IDE hard disk
0/1 image
\n", QEMU_ARCH_ALL)
607 DEF("hdb
", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
608 DEF("hdc
", HAS_ARG, QEMU_OPTION_hdc,
609 "-hdc
/-hdd file use
'file' as IDE hard disk
2/3 image
\n", QEMU_ARCH_ALL)
610 DEF("hdd
", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
612 @item -hda @var{file}
613 @itemx -hdb @var{file}
614 @itemx -hdc @var{file}
615 @itemx -hdd @var{file}
620 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
623 DEF("cdrom
", HAS_ARG, QEMU_OPTION_cdrom,
624 "-cdrom file use
'file' as IDE cdrom
image (cdrom is ide1 master
)\n",
627 @item -cdrom @var{file}
629 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
630 @option{-cdrom} at the same time). You can use the host CD-ROM by
631 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
634 DEF("blockdev
", HAS_ARG, QEMU_OPTION_blockdev,
635 "-blockdev
[driver
=]driver
[,node
-name
=N
][,discard
=ignore|unmap
]\n"
636 " [,cache
.direct
=on|off
][,cache
.no
-flush
=on|off
]\n"
637 " [,read
-only
=on|off
][,detect
-zeroes
=on|off|unmap
]\n"
638 " [,driver specific parameters
...]\n"
639 " configure a block backend
\n", QEMU_ARCH_ALL)
641 @item -blockdev @var{option}[,@var{option}[,@var{option}[,...]]]
644 Define a new block driver node. Some of the options apply to all block drivers,
645 other options are only accepted for a specific block driver. See below for a
646 list of generic options and options for the most common block drivers.
648 Options that expect a reference to another node (e.g. @code{file}) can be
649 given in two ways. Either you specify the node name of an already existing node
650 (file=@var{node-name}), or you define a new node inline, adding options
651 for the referenced node after a dot (file.filename=@var{path},file.aio=native).
653 A block driver node created with @option{-blockdev} can be used for a guest
654 device by specifying its node name for the @code{drive} property in a
655 @option{-device} argument that defines a block device.
658 @item Valid options for any block driver node:
662 Specifies the block driver to use for the given node.
664 This defines the name of the block driver node by which it will be referenced
665 later. The name must be unique, i.e. it must not match the name of a different
666 block driver node, or (if you use @option{-drive} as well) the ID of a drive.
668 If no node name is specified, it is automatically generated. The generated node
669 name is not intended to be predictable and changes between QEMU invocations.
670 For the top level, an explicit node name must be specified.
672 Open the node read-only. Guest write attempts will fail.
674 The host page cache can be avoided with @option{cache.direct=on}. This will
675 attempt to do disk IO directly to the guest's memory. QEMU may still perform an
676 internal copy of the data.
678 In case you don't care about data integrity over host failures, you can use
679 @option{cache.no-flush=on}. This option tells QEMU that it never needs to write
680 any data to the disk but can instead keep things in cache. If anything goes
681 wrong, like your host losing power, the disk storage getting disconnected
682 accidentally, etc. your image will most probably be rendered unusable.
683 @item discard=@var{discard}
684 @var{discard} is one of "ignore
" (or "off
") or "unmap
" (or "on
") and controls
685 whether @code{discard} (also known as @code{trim} or @code{unmap}) requests are
686 ignored or passed to the filesystem. Some machine types may not support
688 @item detect-zeroes=@var{detect-zeroes}
689 @var{detect-zeroes} is "off
", "on
" or "unmap
" and enables the automatic
690 conversion of plain zero writes by the OS to driver specific optimized
691 zero write commands. You may even choose "unmap
" if @var{discard} is set
692 to "unmap
" to allow a zero write to be converted to an @code{unmap} operation.
695 @item Driver-specific options for @code{file}
697 This is the protocol-level block driver for accessing regular files.
701 The path to the image file in the local filesystem
703 Specifies the AIO backend (threads/native, default: threads)
705 Specifies whether the image file is protected with Linux OFD / POSIX locks. The
706 default is to use the Linux Open File Descriptor API if available, otherwise no
707 lock is applied. (auto/on/off, default: auto)
711 -blockdev driver=file,node-name=disk,filename=disk.img
714 @item Driver-specific options for @code{raw}
716 This is the image format block driver for raw images. It is usually
717 stacked on top of a protocol level block driver such as @code{file}.
721 Reference to or definition of the data source block driver node
722 (e.g. a @code{file} driver node)
726 -blockdev driver=file,node-name=disk_file,filename=disk.img
727 -blockdev driver=raw,node-name=disk,file=disk_file
731 -blockdev driver=raw,node-name=disk,file.driver=file,file.filename=disk.img
734 @item Driver-specific options for @code{qcow2}
736 This is the image format block driver for qcow2 images. It is usually
737 stacked on top of a protocol level block driver such as @code{file}.
741 Reference to or definition of the data source block driver node
742 (e.g. a @code{file} driver node)
745 Reference to or definition of the backing file block device (default is taken
746 from the image file). It is allowed to pass @code{null} here in order to disable
747 the default backing file.
750 Whether to enable the lazy refcounts feature (on/off; default is taken from the
754 The maximum total size of the L2 table and refcount block caches in bytes
755 (default: 1048576 bytes or 8 clusters, whichever is larger)
758 The maximum size of the L2 table cache in bytes
759 (default: 4/5 of the total cache size)
761 @item refcount-cache-size
762 The maximum size of the refcount block cache in bytes
763 (default: 1/5 of the total cache size)
765 @item cache-clean-interval
766 Clean unused entries in the L2 and refcount caches. The interval is in seconds.
767 The default value is 0 and it disables this feature.
769 @item pass-discard-request
770 Whether discard requests to the qcow2 device should be forwarded to the data
771 source (on/off; default: on if discard=unmap is specified, off otherwise)
773 @item pass-discard-snapshot
774 Whether discard requests for the data source should be issued when a snapshot
775 operation (e.g. deleting a snapshot) frees clusters in the qcow2 file (on/off;
778 @item pass-discard-other
779 Whether discard requests for the data source should be issued on other
780 occasions where a cluster gets freed (on/off; default: off)
783 Which overlap checks to perform for writes to the image
784 (none/constant/cached/all; default: cached). For details or finer
785 granularity control refer to the QAPI documentation of @code{blockdev-add}.
790 -blockdev driver=file,node-name=my_file,filename=/tmp/disk.qcow2
791 -blockdev driver=qcow2,node-name=hda,file=my_file,overlap-check=none,cache-size=16777216
795 -blockdev driver=qcow2,node-name=disk,file.driver=http,file.filename=http://example.com/image.qcow2
798 @item Driver-specific options for other drivers
799 Please refer to the QAPI documentation of the @code{blockdev-add} QMP command.
805 DEF("drive
", HAS_ARG, QEMU_OPTION_drive,
806 "-drive
[file
=file
][,if=type
][,bus
=n
][,unit
=m
][,media
=d
][,index
=i
]\n"
807 " [,cyls
=c
,heads
=h
,secs
=s
[,trans
=t
]][,snapshot
=on|off
]\n"
808 " [,cache
=writethrough|writeback|none|directsync|unsafe
][,format
=f
]\n"
809 " [,serial
=s
][,addr
=A
][,rerror
=ignore|stop|report
]\n"
810 " [,werror
=ignore|stop|report|enospc
][,id
=name
][,aio
=threads|native
]\n"
811 " [,readonly
=on|off
][,copy
-on
-read
=on|off
]\n"
812 " [,discard
=ignore|unmap
][,detect
-zeroes
=on|off|unmap
]\n"
813 " [[,bps
=b
]|
[[,bps_rd
=r
][,bps_wr
=w
]]]\n"
814 " [[,iops
=i
]|
[[,iops_rd
=r
][,iops_wr
=w
]]]\n"
815 " [[,bps_max
=bm
]|
[[,bps_rd_max
=rm
][,bps_wr_max
=wm
]]]\n"
816 " [[,iops_max
=im
]|
[[,iops_rd_max
=irm
][,iops_wr_max
=iwm
]]]\n"
817 " [[,iops_size
=is
]]\n"
819 " use
'file' as a drive image
\n", QEMU_ARCH_ALL)
821 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
824 Define a new drive. This includes creating a block driver node (the backend) as
825 well as a guest device, and is mostly a shortcut for defining the corresponding
826 @option{-blockdev} and @option{-device} options.
828 @option{-drive} accepts all options that are accepted by @option{-blockdev}. In
829 addition, it knows the following options:
832 @item file=@var{file}
833 This option defines which disk image (@pxref{disk_images}) to use with
834 this drive. If the filename contains comma, you must double it
835 (for instance, "file
=my
,,file
" to use file "my
,file
").
837 Special files such as iSCSI devices can be specified using protocol
838 specific URLs. See the section for "Device URL Syntax
" for more information.
839 @item if=@var{interface}
840 This option defines on which type on interface the drive is connected.
841 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio, none.
842 @item bus=@var{bus},unit=@var{unit}
843 These options define where is connected the drive by defining the bus number and
845 @item index=@var{index}
846 This option defines where is connected the drive by using an index in the list
847 of available connectors of a given interface type.
848 @item media=@var{media}
849 This option defines the type of the media: disk or cdrom.
850 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
851 Force disk physical geometry and the optional BIOS translation (trans=none or
852 lba). These parameters are deprecated, use the corresponding parameters
853 of @code{-device} instead.
854 @item snapshot=@var{snapshot}
855 @var{snapshot} is "on
" or "off
" and controls snapshot mode for the given drive
856 (see @option{-snapshot}).
857 @item cache=@var{cache}
858 @var{cache} is "none
", "writeback
", "unsafe
", "directsync
" or "writethrough
"
859 and controls how the host cache is used to access block data. This is a
860 shortcut that sets the @option{cache.direct} and @option{cache.no-flush}
861 options (as in @option{-blockdev}), and additionally @option{cache.writeback},
862 which provides a default for the @option{write-cache} option of block guest
863 devices (as in @option{-device}). The modes correspond to the following
866 @c Our texi2pod.pl script doesn't support @multitable, so fall back to using
867 @c plain ASCII art (well, UTF-8 art really). This looks okay both in the manpage
868 @c and the HTML output.
870 @ │ cache.writeback cache.direct cache.no-flush
871 ─────────────┼─────────────────────────────────────────────────
872 writeback │ on off off
874 writethrough │ off off off
875 directsync │ off on off
879 The default mode is @option{cache=writeback}.
882 @var{aio} is "threads
", or "native
" and selects between pthread based disk I/O and native Linux AIO.
883 @item format=@var{format}
884 Specify which disk @var{format} will be used rather than detecting
885 the format. Can be used to specify format=raw to avoid interpreting
886 an untrusted format header.
887 @item serial=@var{serial}
888 This option specifies the serial number to assign to the device. This
889 parameter is deprecated, use the corresponding parameter of @code{-device}
891 @item addr=@var{addr}
892 Specify the controller's PCI address (if=virtio only). This parameter is
893 deprecated, use the corresponding parameter of @code{-device} instead.
894 @item werror=@var{action},rerror=@var{action}
895 Specify which @var{action} to take on write and read errors. Valid actions are:
896 "ignore
" (ignore the error and try to continue), "stop
" (pause QEMU),
897 "report
" (report the error to the guest), "enospc
" (pause QEMU only if the
898 host disk is full; report the error to the guest otherwise).
899 The default setting is @option{werror=enospc} and @option{rerror=report}.
900 @item copy-on-read=@var{copy-on-read}
901 @var{copy-on-read} is "on
" or "off
" and enables whether to copy read backing
902 file sectors into the image file.
903 @item bps=@var{b},bps_rd=@var{r},bps_wr=@var{w}
904 Specify bandwidth throttling limits in bytes per second, either for all request
905 types or for reads or writes only. Small values can lead to timeouts or hangs
906 inside the guest. A safe minimum for disks is 2 MB/s.
907 @item bps_max=@var{bm},bps_rd_max=@var{rm},bps_wr_max=@var{wm}
908 Specify bursts in bytes per second, either for all request types or for reads
909 or writes only. Bursts allow the guest I/O to spike above the limit
911 @item iops=@var{i},iops_rd=@var{r},iops_wr=@var{w}
912 Specify request rate limits in requests per second, either for all request
913 types or for reads or writes only.
914 @item iops_max=@var{bm},iops_rd_max=@var{rm},iops_wr_max=@var{wm}
915 Specify bursts in requests per second, either for all request types or for reads
916 or writes only. Bursts allow the guest I/O to spike above the limit
918 @item iops_size=@var{is}
919 Let every @var{is} bytes of a request count as a new request for iops
920 throttling purposes. Use this option to prevent guests from circumventing iops
921 limits by sending fewer but larger requests.
923 Join a throttling quota group with given name @var{g}. All drives that are
924 members of the same group are accounted for together. Use this option to
925 prevent guests from circumventing throttling limits by using many small disks
926 instead of a single larger disk.
929 By default, the @option{cache.writeback=on} mode is used. It will report data
930 writes as completed as soon as the data is present in the host page cache.
931 This is safe as long as your guest OS makes sure to correctly flush disk caches
932 where needed. If your guest OS does not handle volatile disk write caches
933 correctly and your host crashes or loses power, then the guest may experience
936 For such guests, you should consider using @option{cache.writeback=off}. This
937 means that the host page cache will be used to read and write data, but write
938 notification will be sent to the guest only after QEMU has made sure to flush
939 each write to the disk. Be aware that this has a major impact on performance.
941 When using the @option{-snapshot} option, unsafe caching is always used.
943 Copy-on-read avoids accessing the same backing file sectors repeatedly and is
944 useful when the backing file is over a slow network. By default copy-on-read
947 Instead of @option{-cdrom} you can use:
949 qemu-system-i386 -drive file=file,index=2,media=cdrom
952 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
955 qemu-system-i386 -drive file=file,index=0,media=disk
956 qemu-system-i386 -drive file=file,index=1,media=disk
957 qemu-system-i386 -drive file=file,index=2,media=disk
958 qemu-system-i386 -drive file=file,index=3,media=disk
961 You can open an image using pre-opened file descriptors from an fd set:
964 -add-fd fd=3,set=2,opaque="rdwr
:/path
/to
/file
"
965 -add-fd fd=4,set=2,opaque="rdonly
:/path
/to
/file
"
966 -drive file=/dev/fdset/2,index=0,media=disk
969 You can connect a CDROM to the slave of ide0:
971 qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
974 If you don't specify the "file
=" argument, you define an empty drive:
976 qemu-system-i386 -drive if=ide,index=1,media=cdrom
979 Instead of @option{-fda}, @option{-fdb}, you can use:
981 qemu-system-i386 -drive file=file,index=0,if=floppy
982 qemu-system-i386 -drive file=file,index=1,if=floppy
985 By default, @var{interface} is "ide
" and @var{index} is automatically
988 qemu-system-i386 -drive file=a -drive file=b"
992 qemu
-system
-i386
-hda a
-hdb b
996 DEF("mtdblock", HAS_ARG
, QEMU_OPTION_mtdblock
,
997 "-mtdblock file use 'file' as on-board Flash memory image\n",
1000 @item
-mtdblock @
var{file
}
1002 Use @
var{file
} as on
-board Flash memory image
.
1005 DEF("sd", HAS_ARG
, QEMU_OPTION_sd
,
1006 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL
)
1008 @item
-sd @
var{file
}
1010 Use @
var{file
} as SecureDigital card image
.
1013 DEF("pflash", HAS_ARG
, QEMU_OPTION_pflash
,
1014 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL
)
1016 @item
-pflash @
var{file
}
1018 Use @
var{file
} as a parallel flash image
.
1021 DEF("snapshot", 0, QEMU_OPTION_snapshot
,
1022 "-snapshot write to temporary files instead of disk image files\n",
1027 Write to temporary files instead of disk image files
. In
this case,
1028 the raw disk image you use is not written back
. You can however force
1029 the write back by pressing @key
{C
-a s
} (@pxref
{disk_images
}).
1032 DEF("fsdev", HAS_ARG
, QEMU_OPTION_fsdev
,
1033 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
1034 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n"
1035 " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n"
1036 " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n"
1037 " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n"
1038 " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n"
1039 " [[,throttling.iops-size=is]]\n",
1044 @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
}][,fmode
=@
var{fmode
}][,dmode
=@
var{dmode
}]
1046 Define a
new file system device
. Valid options are
:
1048 @item @
var{fsdriver
}
1049 This option specifies the fs driver backend to use
.
1050 Currently
"local", "handle" and
"proxy" file system drivers are supported
.
1052 Specifies identifier
for this device
1053 @item path
=@
var{path
}
1054 Specifies the export path
for the file system device
. Files under
1055 this path will be available to the
9p client on the guest
.
1056 @item security_model
=@
var{security_model
}
1057 Specifies the security model to be used
for this export path
.
1058 Supported security models are
"passthrough", "mapped-xattr", "mapped-file" and
"none".
1059 In
"passthrough" security model
, files are stored
using the same
1060 credentials as they are created on the guest
. This requires QEMU
1061 to run as root
. In
"mapped-xattr" security model
, some of the file
1062 attributes like uid
, gid
, mode bits and link target are stored as
1063 file attributes
. For
"mapped-file" these attributes are stored
in the
1064 hidden
.virtfs_metadata directory
. Directories exported by
this security model cannot
1065 interact with other unix tools
. "none" security model is same as
1066 passthrough except the sever won
't report failures if it fails to
1067 set file attributes like ownership. Security model is mandatory
1068 only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
1069 security model as a parameter
.
1070 @item writeout
=@
var{writeout
}
1071 This is an optional argument
. The only supported value is
"immediate".
1072 This means that host page cache will be used to read and write data but
1073 write notification will be sent to the guest only when the data has been
1074 reported as written by the storage subsystem
.
1076 Enables exporting
9p share as a readonly mount
for guests
. By
default
1077 read
-write access is given
.
1078 @item socket
=@
var{socket
}
1079 Enables proxy filesystem driver to use passed socket file
for communicating
1080 with virtfs
-proxy
-helper
1081 @item sock_fd
=@
var{sock_fd
}
1082 Enables proxy filesystem driver to use passed socket descriptor
for
1083 communicating with virtfs
-proxy
-helper
. Usually a helper like libvirt
1084 will create socketpair and pass one of the fds as sock_fd
1085 @item fmode
=@
var{fmode
}
1086 Specifies the
default mode
for newly created files on the host
. Works only
1087 with security models
"mapped-xattr" and
"mapped-file".
1088 @item dmode
=@
var{dmode
}
1089 Specifies the
default mode
for newly created directories on the host
. Works
1090 only with security models
"mapped-xattr" and
"mapped-file".
1093 -fsdev option is used along with
-device driver
"virtio-9p-pci".
1094 @item
-device virtio
-9p
-pci
,fsdev
=@
var{id
},mount_tag
=@
var{mount_tag
}
1095 Options
for virtio
-9p
-pci driver are
:
1097 @item fsdev
=@
var{id
}
1098 Specifies the id value specified along with
-fsdev option
1099 @item mount_tag
=@
var{mount_tag
}
1100 Specifies the tag name to be used by the guest to mount
this export point
1105 DEF("virtfs", HAS_ARG
, QEMU_OPTION_virtfs
,
1106 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
1107 " [,id=id][,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n",
1112 @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
}][,fmode
=@
var{fmode
}][,dmode
=@
var{dmode
}]
1115 The general form of a Virtual File system pass
-through options are
:
1117 @item @
var{fsdriver
}
1118 This option specifies the fs driver backend to use
.
1119 Currently
"local", "handle" and
"proxy" file system drivers are supported
.
1121 Specifies identifier
for this device
1122 @item path
=@
var{path
}
1123 Specifies the export path
for the file system device
. Files under
1124 this path will be available to the
9p client on the guest
.
1125 @item security_model
=@
var{security_model
}
1126 Specifies the security model to be used
for this export path
.
1127 Supported security models are
"passthrough", "mapped-xattr", "mapped-file" and
"none".
1128 In
"passthrough" security model
, files are stored
using the same
1129 credentials as they are created on the guest
. This requires QEMU
1130 to run as root
. In
"mapped-xattr" security model
, some of the file
1131 attributes like uid
, gid
, mode bits and link target are stored as
1132 file attributes
. For
"mapped-file" these attributes are stored
in the
1133 hidden
.virtfs_metadata directory
. Directories exported by
this security model cannot
1134 interact with other unix tools
. "none" security model is same as
1135 passthrough except the sever won
't report failures if it fails to
1136 set file attributes like ownership. Security model is mandatory only
1137 for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
1138 model as a parameter
.
1139 @item writeout
=@
var{writeout
}
1140 This is an optional argument
. The only supported value is
"immediate".
1141 This means that host page cache will be used to read and write data but
1142 write notification will be sent to the guest only when the data has been
1143 reported as written by the storage subsystem
.
1145 Enables exporting
9p share as a readonly mount
for guests
. By
default
1146 read
-write access is given
.
1147 @item socket
=@
var{socket
}
1148 Enables proxy filesystem driver to use passed socket file
for
1149 communicating with virtfs
-proxy
-helper
. Usually a helper like libvirt
1150 will create socketpair and pass one of the fds as sock_fd
1152 Enables proxy filesystem driver to use passed
'sock_fd' as the socket
1153 descriptor
for interfacing with virtfs
-proxy
-helper
1154 @item fmode
=@
var{fmode
}
1155 Specifies the
default mode
for newly created files on the host
. Works only
1156 with security models
"mapped-xattr" and
"mapped-file".
1157 @item dmode
=@
var{dmode
}
1158 Specifies the
default mode
for newly created directories on the host
. Works
1159 only with security models
"mapped-xattr" and
"mapped-file".
1163 DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth
,
1164 "-virtfs_synth Create synthetic file system image\n",
1168 @findex
-virtfs_synth
1169 Create synthetic file system image
1172 DEF("iscsi", HAS_ARG
, QEMU_OPTION_iscsi
,
1173 "-iscsi [user=user][,password=password]\n"
1174 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
1175 " [,initiator-name=initiator-iqn][,id=target-iqn]\n"
1176 " [,timeout=timeout]\n"
1177 " iSCSI session parameters\n", QEMU_ARCH_ALL
)
1182 Configure iSCSI session parameters
.
1190 DEFHEADING(USB options
:)
1195 DEF("usb", 0, QEMU_OPTION_usb
,
1196 "-usb enable the USB driver (if it is not used by default yet)\n",
1201 Enable the USB
driver (if it is not used by
default yet
).
1204 DEF("usbdevice", HAS_ARG
, QEMU_OPTION_usbdevice
,
1205 "-usbdevice name add the host or guest USB device 'name'\n",
1209 @item
-usbdevice @
var{devname
}
1211 Add the USB device @
var{devname
}. Note that
this option is deprecated
,
1212 please use @code
{-device usb
-...} instead
. @xref
{usb_devices
}.
1217 Virtual Mouse
. This will
override the PS
/2 mouse emulation when activated
.
1220 Pointer device that uses absolute
coordinates (like a touchscreen
). This
1221 means QEMU is able to report the mouse position without having to grab the
1222 mouse
. Also overrides the PS
/2 mouse emulation when activated
.
1225 Braille device
. This will use BrlAPI to display the braille output on a real
1236 DEFHEADING(Display options
:)
1241 DEF("display", HAS_ARG
, QEMU_OPTION_display
,
1242 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
1243 " [,window_close=on|off][,gl=on|core|es|off]\n"
1244 "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n"
1245 "-display vnc=<display>[,<optargs>]\n"
1248 " select display type\n"
1249 "The default display is equivalent to\n"
1250 #
if defined(CONFIG_GTK
)
1251 "\t\"-display gtk\"\n"
1252 #elif
defined(CONFIG_SDL
)
1253 "\t\"-display sdl\"\n"
1254 #elif
defined(CONFIG_COCOA
)
1255 "\t\"-display cocoa\"\n"
1256 #elif
defined(CONFIG_VNC
)
1257 "\t\"-vnc localhost:0,to=99,id=default\"\n"
1259 "\t\"-display none\"\n"
1263 @item
-display @
var{type
}
1265 Select type of display to use
. This option is a replacement
for the
1266 old style
-sdl
/-curses
/... options
. Valid values
for @
var{type
} are
1269 Display video output via
SDL (usually
in a separate graphics
1270 window
; see the SDL documentation
for other possibilities
).
1272 Display video output via curses
. For graphics device models which
1273 support a text mode
, QEMU can display
this output
using a
1274 curses
/ncurses
interface. Nothing is displayed when the graphics
1275 device is
in graphical mode or
if the graphics device does not support
1276 a text mode
. Generally only the VGA device models support text mode
.
1278 Do not display video output
. The guest will still see an emulated
1279 graphics card
, but its output will not be displayed to the QEMU
1280 user
. This option differs from the
-nographic option
in that it
1281 only affects what is done with video output
; -nographic also changes
1282 the destination of the serial and parallel port data
.
1284 Display video output
in a GTK window
. This
interface provides drop
-down
1285 menus and other UI elements to configure and control the VM during
1288 Start a VNC server on display
<arg
>
1292 DEF("nographic", 0, QEMU_OPTION_nographic
,
1293 "-nographic disable graphical output and redirect serial I/Os to console\n",
1298 Normally
, if QEMU is compiled with graphical window support
, it displays
1299 output such as guest graphics
, guest console
, and the QEMU monitor
in a
1300 window
. With
this option
, you can totally disable graphical output so
1301 that QEMU is a simple command line application
. The emulated serial port
1302 is redirected on the console and muxed with the
monitor (unless
1303 redirected elsewhere explicitly
). Therefore
, you can still use QEMU to
1304 debug a Linux kernel with a serial console
. Use @key
{C
-a h
} for help on
1305 switching between the console and monitor
.
1308 DEF("curses", 0, QEMU_OPTION_curses
,
1309 "-curses shorthand for -display curses\n",
1314 Normally
, if QEMU is compiled with graphical window support
, it displays
1315 output such as guest graphics
, guest console
, and the QEMU monitor
in a
1316 window
. With
this option
, QEMU can display the VGA output when
in text
1317 mode
using a curses
/ncurses
interface. Nothing is displayed
in graphical
1321 DEF("no-frame", 0, QEMU_OPTION_no_frame
,
1322 "-no-frame open SDL window without a frame and window decorations\n",
1327 Do not use decorations
for SDL windows and start them
using the whole
1328 available screen space
. This makes the
using QEMU
in a dedicated desktop
1329 workspace more convenient
.
1332 DEF("alt-grab", 0, QEMU_OPTION_alt_grab
,
1333 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
1338 Use Ctrl
-Alt
-Shift to grab
mouse (instead of Ctrl
-Alt
). Note that
this also
1339 affects the special
keys (for fullscreen
, monitor
-mode switching
, etc
).
1342 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab
,
1343 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
1348 Use Right
-Ctrl to grab
mouse (instead of Ctrl
-Alt
). Note that
this also
1349 affects the special
keys (for fullscreen
, monitor
-mode switching
, etc
).
1352 DEF("no-quit", 0, QEMU_OPTION_no_quit
,
1353 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL
)
1357 Disable SDL window close capability
.
1360 DEF("sdl", 0, QEMU_OPTION_sdl
,
1361 "-sdl shorthand for -display sdl\n", QEMU_ARCH_ALL
)
1368 DEF("spice", HAS_ARG
, QEMU_OPTION_spice
,
1369 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
1370 " [,x509-key-file=<file>][,x509-key-password=<file>]\n"
1371 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
1372 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n"
1373 " [,tls-ciphers=<list>]\n"
1374 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
1375 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
1376 " [,sasl][,password=<secret>][,disable-ticketing]\n"
1377 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
1378 " [,jpeg-wan-compression=[auto|never|always]]\n"
1379 " [,zlib-glz-wan-compression=[auto|never|always]]\n"
1380 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
1381 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
1382 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
1383 " [,gl=[on|off]][,rendernode=<file>]\n"
1385 " at least one of {port, tls-port} is mandatory\n",
1388 @item
-spice @
var{option
}[,@
var{option
}[,...]]
1390 Enable the spice remote desktop protocol
. Valid options are
1395 Set the TCP port spice is listening on
for plaintext channels
.
1398 Set the IP address spice is listening on
. Default is any address
.
1403 Force
using the specified IP version
.
1405 @item password
=<secret
>
1406 Set the password you need to authenticate
.
1409 Require that the client use SASL to authenticate with the spice
.
1410 The exact choice of authentication method used is controlled from the
1411 system
/ user
's SASL configuration file for the 'qemu
' service. This
1412 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1413 unprivileged user, an environment variable SASL_CONF_PATH can be used
1414 to make it search alternate locations for the service config.
1415 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1416 it is recommended that SASL always be combined with the 'tls
' and
1417 'x509
' settings to enable use of SSL and server certificates. This
1418 ensures a data encryption preventing compromise of authentication
1421 @item disable-ticketing
1422 Allow client connects without authentication.
1424 @item disable-copy-paste
1425 Disable copy paste between the client and the guest.
1427 @item disable-agent-file-xfer
1428 Disable spice-vdagent based file-xfer between the client and the guest.
1431 Set the TCP port spice is listening on for encrypted channels.
1433 @item x509-dir=<dir>
1434 Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1436 @item x509-key-file=<file>
1437 @itemx x509-key-password=<file>
1438 @itemx x509-cert-file=<file>
1439 @itemx x509-cacert-file=<file>
1440 @itemx x509-dh-key-file=<file>
1441 The x509 file names can also be configured individually.
1443 @item tls-ciphers=<list>
1444 Specify which ciphers to use.
1446 @item tls-channel=[main|display|cursor|inputs|record|playback]
1447 @itemx plaintext-channel=[main|display|cursor|inputs|record|playback]
1448 Force specific channel to be used with or without TLS encryption. The
1449 options can be specified multiple times to configure multiple
1450 channels. The special name "default" can be used to set the default
1451 mode. For channels which are not explicitly forced into one mode the
1452 spice client is allowed to pick tls/plaintext as he pleases.
1454 @item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1455 Configure image compression (lossless).
1456 Default is auto_glz.
1458 @item jpeg-wan-compression=[auto|never|always]
1459 @itemx zlib-glz-wan-compression=[auto|never|always]
1460 Configure wan image compression (lossy for slow links).
1463 @item streaming-video=[off|all|filter]
1464 Configure video stream detection. Default is off.
1466 @item agent-mouse=[on|off]
1467 Enable/disable passing mouse events via vdagent. Default is on.
1469 @item playback-compression=[on|off]
1470 Enable/disable audio stream compression (using celt 0.5.1). Default is on.
1472 @item seamless-migration=[on|off]
1473 Enable/disable spice seamless migration. Default is off.
1476 Enable/disable OpenGL context. Default is off.
1478 @item rendernode=<file>
1479 DRM render node for OpenGL rendering. If not specified, it will pick
1480 the first available. (Since 2.9)
1485 DEF("portrait", 0, QEMU_OPTION_portrait,
1486 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
1491 Rotate graphical output 90 deg left (only PXA LCD).
1494 DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1495 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
1498 @item -rotate @var{deg}
1500 Rotate graphical output some deg left (only PXA LCD).
1503 DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1504 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n"
1505 " select video card type\n", QEMU_ARCH_ALL)
1507 @item -vga @var{type}
1509 Select type of VGA card to emulate. Valid values for @var{type} are
1512 Cirrus Logic GD5446 Video card. All Windows versions starting from
1513 Windows 95 should recognize and use this graphic card. For optimal
1514 performances, use 16 bit color depth in the guest and the host OS.
1515 (This card was the default before QEMU 2.2)
1517 Standard VGA card with Bochs VBE extensions. If your guest OS
1518 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1519 to use high resolution modes (>= 1280x1024x16) then you should use
1520 this option. (This card is the default since QEMU 2.2)
1522 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1523 recent XFree86/XOrg server or Windows guest with a driver for this
1526 QXL paravirtual graphic card. It is VGA compatible (including VESA
1527 2.0 VBE support). Works best with qxl guest drivers installed though.
1528 Recommended choice when using the spice protocol.
1530 (sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1531 sun4m machines and offers both 8-bit and 24-bit colour depths at a
1532 fixed resolution of 1024x768.
1534 (sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1535 for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1536 resolutions aimed at people wishing to run older Solaris versions.
1544 DEF("full-screen", 0, QEMU_OPTION_full_screen,
1545 "-full-screen start in full screen\n", QEMU_ARCH_ALL)
1548 @findex -full-screen
1549 Start in full screen.
1552 DEF("g", 1, QEMU_OPTION_g ,
1553 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
1554 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1556 @item -g @var{width}x@var{height}[x@var{depth}]
1558 Set the initial graphical resolution and depth (PPC, SPARC only).
1561 DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1562 "-vnc <display> shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL)
1564 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1566 Normally, if QEMU is compiled with graphical window support, it displays
1567 output such as guest graphics, guest console, and the QEMU monitor in a
1568 window. With this option, you can have QEMU listen on VNC display
1569 @var{display} and redirect the VGA display over the VNC session. It is
1570 very useful to enable the usb tablet device when using this option
1571 (option @option{-device usb-tablet}). When using the VNC display, you
1572 must use the @option{-k} parameter to set the keyboard layout if you are
1573 not using en-us. Valid syntax for the @var{display} is
1579 With this option, QEMU will try next available VNC @var{display}s, until the
1580 number @var{L}, if the origianlly defined "-vnc @var{display}" is not
1581 available, e.g. port 5900+@var{display} is already used by another
1582 application. By default, to=0.
1584 @item @var{host}:@var{d}
1586 TCP connections will only be allowed from @var{host} on display @var{d}.
1587 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1588 be omitted in which case the server will accept connections from any host.
1590 @item unix:@var{path}
1592 Connections will be allowed over UNIX domain sockets where @var{path} is the
1593 location of a unix socket to listen for connections on.
1597 VNC is initialized but not started. The monitor @code{change} command
1598 can be used to later start the VNC server.
1602 Following the @var{display} value there may be one or more @var{option} flags
1603 separated by commas. Valid options are
1609 Connect to a listening VNC client via a ``reverse'' connection. The
1610 client is specified by the @var{display}. For reverse network
1611 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1612 is a TCP port number, not a display number.
1616 Opens an additional TCP listening port dedicated to VNC Websocket connections.
1617 If a bare @var{websocket} option is given, the Websocket port is
1618 5700+@var{display}. An alternative port can be specified with the
1619 syntax @code{websocket}=@var{port}.
1621 If @var{host} is specified connections will only be allowed from this host.
1622 It is possible to control the websocket listen address independently, using
1623 the syntax @code{websocket}=@var{host}:@var{port}.
1625 If no TLS credentials are provided, the websocket connection runs in
1626 unencrypted mode. If TLS credentials are provided, the websocket connection
1627 requires encrypted client connections.
1631 Require that password based authentication is used for client connections.
1633 The password must be set separately using the @code{set_password} command in
1634 the @ref{pcsys_monitor}. The syntax to change your password is:
1635 @code{set_password <protocol> <password>} where <protocol> could be either
1638 If you would like to change <protocol> password expiration, you should use
1639 @code{expire_password <protocol> <expiration-time>} where expiration time could
1640 be one of the following options: now, never, +seconds or UNIX time of
1641 expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1642 to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1645 You can also use keywords "now" or "never" for the expiration time to
1646 allow <protocol> password to expire immediately or never expire.
1648 @item tls-creds=@var{ID}
1650 Provides the ID of a set of TLS credentials to use to secure the
1651 VNC server. They will apply to both the normal VNC server socket
1652 and the websocket socket (if enabled). Setting TLS credentials
1653 will cause the VNC server socket to enable the VeNCrypt auth
1654 mechanism. The credentials should have been previously created
1655 using the @option{-object tls-creds} argument.
1657 The @option{tls-creds} parameter obsoletes the @option{tls},
1658 @option{x509}, and @option{x509verify} options, and as such
1659 it is not permitted to set both new and old type options at
1664 Require that client use TLS when communicating with the VNC server. This
1665 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1666 attack. It is recommended that this option be combined with either the
1667 @option{x509} or @option{x509verify} options.
1669 This option is now deprecated in favor of using the @option{tls-creds}
1672 @item x509=@var{/path/to/certificate/dir}
1674 Valid if @option{tls} is specified. Require that x509 credentials are used
1675 for negotiating the TLS session. The server will send its x509 certificate
1676 to the client. It is recommended that a password be set on the VNC server
1677 to provide authentication of the client when this is used. The path following
1678 this option specifies where the x509 certificates are to be loaded from.
1679 See the @ref{vnc_security} section for details on generating certificates.
1681 This option is now deprecated in favour of using the @option{tls-creds}
1684 @item x509verify=@var{/path/to/certificate/dir}
1686 Valid if @option{tls} is specified. Require that x509 credentials are used
1687 for negotiating the TLS session. The server will send its x509 certificate
1688 to the client, and request that the client send its own x509 certificate.
1689 The server will validate the client's certificate against the CA certificate
,
1690 and reject clients when validation fails
. If the certificate authority is
1691 trusted
, this is a sufficient authentication mechanism
. You may still wish
1692 to set a password on the VNC server as a second authentication layer
. The
1693 path following
this option specifies where the x509 certificates are to
1694 be loaded from
. See the @ref
{vnc_security
} section
for details on generating
1697 This option is now deprecated
in favour of
using the @option
{tls
-creds
}
1702 Require that the client use SASL to authenticate with the VNC server
.
1703 The exact choice of authentication method used is controlled from the
1704 system
/ user
's SASL configuration file for the 'qemu
' service. This
1705 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1706 unprivileged user, an environment variable SASL_CONF_PATH can be used
1707 to make it search alternate locations for the service config.
1708 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1709 it is recommended that SASL always be combined with the 'tls
' and
1710 'x509
' settings to enable use of SSL and server certificates. This
1711 ensures a data encryption preventing compromise of authentication
1712 credentials. See the @ref{vnc_security} section for details on using
1713 SASL authentication.
1717 Turn on access control lists for checking of the x509 client certificate
1718 and SASL party. For x509 certs, the ACL check is made against the
1719 certificate's distinguished name
. This is something that looks like
1720 @code
{C
=GB
,O
=ACME
,L
=Boston
,CN
=bob
}. For SASL party
, the ACL check is
1721 made against the username
, which depending on the SASL plugin
, may
1722 include a realm component
, eg @code
{bob
} or @code
{bob@@EXAMPLE
.COM
}.
1723 When the @option
{acl
} flag is set
, the initial access list will be
1724 empty
, with a @code
{deny
} policy
. Thus no one will be allowed to
1725 use the VNC server until the ACLs have been loaded
. This can be
1726 achieved
using the @code
{acl
} monitor command
.
1730 Enable lossy compression
methods (gradient
, JPEG
, ...). If
this
1731 option is set
, VNC client may receive lossy framebuffer updates
1732 depending on its encoding settings
. Enabling
this option can save
1733 a lot of bandwidth at the expense of quality
.
1737 Disable adaptive encodings
. Adaptive encodings are enabled by
default.
1738 An adaptive encoding will
try to detect frequently updated screen regions
,
1739 and send updates
in these regions
using a lossy
encoding (like JPEG
).
1740 This can be really helpful to save bandwidth when playing videos
. Disabling
1741 adaptive encodings restores the original
static behavior of encodings
1744 @item share
=[allow
-exclusive|force
-shared|ignore
]
1746 Set display sharing policy
. 'allow-exclusive' allows clients to ask
1747 for exclusive access
. As suggested by the rfb spec
this is
1748 implemented by dropping other connections
. Connecting multiple
1749 clients
in parallel requires all clients asking
for a shared session
1750 (vncviewer
: -shared
switch). This is the
default. 'force-shared'
1751 disables exclusive client access
. Useful
for shared desktop sessions
,
1752 where you don
't want someone forgetting specify -shared disconnect
1753 everybody else. 'ignore
' completely ignores the shared flag and
1754 allows everybody connect unconditionally. Doesn't conform to the rfb
1755 spec but is traditional QEMU behavior
.
1759 Set keyboard delay
, for key down and key up events
, in milliseconds
.
1760 Default is
10. Keyboards are low
-bandwidth devices
, so
this slowdown
1761 can help the device and guest to keep up and not lose events
in case
1762 events are arriving
in bulk
. Possible causes
for the latter are flaky
1763 network connections
, or scripts
for automated testing
.
1771 ARCHHEADING(, QEMU_ARCH_I386
)
1773 ARCHHEADING(i386 target only
:, QEMU_ARCH_I386
)
1778 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack
,
1779 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1784 Use it when installing Windows
2000 to avoid a disk full bug
. After
1785 Windows
2000 is installed
, you no longer need
this option (this option
1786 slows down the IDE transfers
).
1789 HXCOMM Deprecated by
-rtc
1790 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack
, "", QEMU_ARCH_I386
)
1792 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk
,
1793 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1796 @item
-no
-fd
-bootchk
1797 @findex
-no
-fd
-bootchk
1798 Disable boot signature checking
for floppy disks
in BIOS
. May
1799 be needed to boot from old floppy disks
.
1802 DEF("no-acpi", 0, QEMU_OPTION_no_acpi
,
1803 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM
)
1807 Disable
ACPI (Advanced Configuration and Power Interface
) support
. Use
1808 it
if your guest OS complains about ACPI
problems (PC target machine
1812 DEF("no-hpet", 0, QEMU_OPTION_no_hpet
,
1813 "-no-hpet disable HPET\n", QEMU_ARCH_I386
)
1817 Disable HPET support
.
1820 DEF("acpitable", HAS_ARG
, QEMU_OPTION_acpitable
,
1821 "-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"
1822 " ACPI table description\n", QEMU_ARCH_I386
)
1824 @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
}]...]
1826 Add ACPI table with specified header fields and context from specified files
.
1827 For file
=, take whole ACPI table from the specified files
, including all
1828 ACPI
headers (possible overridden by other options
).
1829 For data
=, only data
1830 portion of the table is used
, all header information is specified
in the
1832 If a SLIC table is supplied to QEMU
, then the SLIC
's oem_id and oem_table_id
1833 fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order
1834 to ensure the field matches required by the Microsoft SLIC spec and the ACPI
1838 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1839 "-smbios file=binary\n"
1840 " load SMBIOS entry from binary file\n"
1841 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1843 " specify SMBIOS type 0 fields\n"
1844 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1845 " [,uuid=uuid][,sku=str][,family=str]\n"
1846 " specify SMBIOS type 1 fields\n"
1847 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1848 " [,asset=str][,location=str]\n"
1849 " specify SMBIOS type 2 fields\n"
1850 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n"
1852 " specify SMBIOS type 3 fields\n"
1853 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n"
1854 " [,asset=str][,part=str]\n"
1855 " specify SMBIOS type 4 fields\n"
1856 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n"
1857 " [,asset=str][,part=str][,speed=%d]\n"
1858 " specify SMBIOS type 17 fields\n",
1859 QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1861 @item -smbios file=@var{binary}
1863 Load SMBIOS entry from binary file.
1865 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1866 Specify SMBIOS type 0 fields
1868 @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}]
1869 Specify SMBIOS type 1 fields
1871 @item -smbios type=2[,manufacturer=@var{str}][,product=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,location=@var{str}][,family=@var{str}]
1872 Specify SMBIOS type 2 fields
1874 @item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}]
1875 Specify SMBIOS type 3 fields
1877 @item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}]
1878 Specify SMBIOS type 4 fields
1880 @item -smbios type=17[,loc_pfx=@var{str}][,bank=@var{str}][,manufacturer=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}][,speed=@var{%d}]
1881 Specify SMBIOS type 17 fields
1889 DEFHEADING(Network options:)
1894 HXCOMM Legacy slirp options (now moved to -net user):
1896 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1897 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1898 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1900 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1904 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1906 "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n"
1907 " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n"
1908 " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n"
1909 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,domainname=domain]\n"
1910 " [,tftp=dir][,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1912 "[,smb=dir[,smbserver=addr]]\n"
1914 " configure a user mode network backend with ID 'str
',\n"
1915 " its DHCP server and optional services\n"
1918 "-netdev tap,id=str,ifname=name\n"
1919 " configure a host TAP network backend with ID 'str
'\n"
1921 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n"
1922 " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n"
1923 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n"
1925 " configure a host TAP network backend with ID 'str
'\n"
1926 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1927 " use network scripts 'file
' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1928 " to configure it and 'dfile
' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1929 " to deconfigure it\n"
1930 " use '[down
]script
=no
' to disable script execution\n"
1931 " use network helper 'helper
' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1933 " use 'fd
=h
' to connect to an already opened TAP interface\n"
1934 " use 'fds
=x
:y
:...:z
' to connect to already opened multiqueue capable TAP interfaces\n"
1935 " use 'sndbuf
=nbytes
' to limit the size of the send buffer (the\n"
1936 " default is disabled 'sndbuf
=0' to enable flow control set 'sndbuf
=1048576')\n"
1937 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1938 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1939 " use vhost=on to enable experimental in kernel accelerator\n"
1940 " (only has effect for virtio guests which use MSIX)\n"
1941 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1942 " use 'vhostfd
=h
' to connect to an already opened vhost net device\n"
1943 " use 'vhostfds
=x
:y
:...:z to connect to multiple already opened vhost net devices
\n"
1944 " use
'queues=n' to specify the number of queues to be created
for multiqueue TAP
\n"
1945 " use
'poll-us=n' to speciy the maximum number of microseconds that could be
\n"
1946 " spent on busy polling
for vhost net
\n"
1947 "-netdev bridge
,id
=str
[,br
=bridge
][,helper
=helper
]\n"
1948 " configure a host TAP network backend with ID
'str' that is
\n"
1949 " connected to a
bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1950 " using the program
'helper (default=" DEFAULT_BRIDGE_HELPER ")\n"
1953 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n"
1954 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n"
1955 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n"
1956 " [,rxcookie=rxcookie][,offset=offset]\n"
1957 " configure a network backend with ID 'str
' connected to\n"
1958 " an Ethernet over L2TPv3 pseudowire.\n"
1959 " Linux kernel 3.3+ as well as most routers can talk\n"
1960 " L2TPv3. This transport allows connecting a VM to a VM,\n"
1961 " VM to a router and even VM to Host. It is a nearly-universal\n"
1962 " standard (RFC3391). Note - this implementation uses static\n"
1963 " pre-configured tunnels (same as the Linux kernel).\n"
1964 " use 'src
=' to specify source address\n"
1965 " use 'dst
=' to specify destination address\n"
1966 " use 'udp
=on
' to specify udp encapsulation\n"
1967 " use 'srcport
=' to specify source udp port\n"
1968 " use 'dstport
=' to specify destination udp port\n"
1969 " use 'ipv6
=on
' to force v6\n"
1970 " L2TPv3 uses cookies to prevent misconfiguration as\n"
1971 " well as a weak security measure\n"
1972 " use 'rxcookie
=0x012345678' to specify a rxcookie\n"
1973 " use 'txcookie
=0x012345678' to specify a txcookie\n"
1974 " use 'cookie64
=on
' to set cookie size to 64 bit, otherwise 32\n"
1975 " use 'counter
=off
' to force a 'cut
-down
' L2TPv3 with no counter\n"
1976 " use 'pincounter
=on
' to work around broken counter handling in peer\n"
1977 " use 'offset
=X
' to add an extra offset between header and data\n"
1979 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n"
1980 " configure a network backend to connect to another network\n"
1981 " using a socket connection\n"
1982 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1983 " configure a network backend to connect to a multicast maddr and port\n"
1984 " use 'localaddr
=addr
' to specify the host address to send packets from\n"
1985 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
1986 " configure a network backend to connect to another network\n"
1987 " using an UDP tunnel\n"
1989 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1990 " configure a network backend to connect to port 'n
' of a vde switch\n"
1991 " running on host and listening for incoming connections on 'socketpath
'.\n"
1992 " Use group 'groupname
' and mode 'octalmode
' to change default\n"
1993 " ownership and permissions for communication port.\n"
1995 #ifdef CONFIG_NETMAP
1996 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n"
1997 " attach to the existing netmap-enabled network interface 'name
', or to a\n"
1998 " VALE port (created on the fly) called 'name
' ('nmname
' is name of the \n"
1999 " netmap device, defaults to '/dev
/netmap
')\n"
2002 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n"
2003 " configure a vhost-user network, backed by a chardev 'dev
'\n"
2005 "-netdev hubport,id=str,hubid=n[,netdev=nd]\n"
2006 " configure a hub port on the hub with ID 'n
'\n", QEMU_ARCH_ALL)
2007 DEF("nic", HAS_ARG, QEMU_OPTION_nic,
2018 #ifdef CONFIG_NETMAP
2024 "socket][,option][,...][mac=macaddr]\n"
2025 " initialize an on-board / default host NIC (using MAC address\n"
2026 " macaddr) and connect it to the given host network backend\n"
2027 "-nic none use it alone to have zero network devices (the default is to\n"
2028 " provided a 'user
' network connection)\n",
2030 DEF("net", HAS_ARG, QEMU_OPTION_net,
2031 "-net nic[,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
2032 " configure or create an on-board (or machine default) NIC and\n"
2033 " connect it to hub 0 (please use -nic unless you need a hub)\n"
2043 #ifdef CONFIG_NETMAP
2046 "socket][,option][,option][,...]\n"
2047 " old way to initialize a host network interface\n"
2048 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL)
2050 @item -nic [tap|bridge|user|l2tpv3|vde|netmap|vhost-user|socket][,...][,mac=macaddr][,model=mn]
2052 This option is a shortcut for configuring both the on-board (default) guest
2053 NIC hardware and the host network backend in one go. The host backend options
2054 are the same as with the corresponding @option{-netdev} options below.
2055 The guest NIC model can be set with @option{model=@var{modelname}}.
2056 Use @option{model=help} to list the available device types.
2057 The hardware MAC address can be set with @option{mac=@var{macaddr}}.
2059 The following two example do exactly the same, to show how @option{-nic} can
2060 be used to shorten the command line length (note that the e1000 is the default
2061 on i386, so the @option{model=e1000} parameter could even be omitted here, too):
2063 qemu-system-i386 -netdev user,id=n1,ipv6=off -device e1000,netdev=n1,mac=52:54:98:76:54:32
2064 qemu-system-i386 -nic user,ipv6=off,model=e1000,mac=52:54:98:76:54:32
2068 Indicate that no network devices should be configured. It is used to override
2069 the default configuration (default NIC with ``user'' host network backend)
2070 which is activated if no other networking options are provided.
2072 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
2074 Configure user mode host network backend which requires no administrator
2075 privilege to run. Valid options are:
2079 Assign symbolic name for use in monitor commands.
2081 @item ipv4=on|off and ipv6=on|off
2082 Specify that either IPv4 or IPv6 must be enabled. If neither is specified
2083 both protocols are enabled.
2085 @item net=@var{addr}[/@var{mask}]
2086 Set IP network address the guest will see. Optionally specify the netmask,
2087 either in the form a.b.c.d or as number of valid top-most bits. Default is
2090 @item host=@var{addr}
2091 Specify the guest-visible address of the host. Default is the 2nd IP in the
2092 guest network, i.e. x.x.x.2.
2094 @item ipv6-net=@var{addr}[/@var{int}]
2095 Set IPv6 network address the guest will see (default is fec0::/64). The
2096 network prefix is given in the usual hexadecimal IPv6 address
2097 notation. The prefix size is optional, and is given as the number of
2098 valid top-most bits (default is 64).
2100 @item ipv6-host=@var{addr}
2101 Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in
2102 the guest network, i.e. xxxx::2.
2104 @item restrict=on|off
2105 If this option is enabled, the guest will be isolated, i.e. it will not be
2106 able to contact the host and no guest IP packets will be routed over the host
2107 to the outside. This option does not affect any explicitly set forwarding rules.
2109 @item hostname=@var{name}
2110 Specifies the client hostname reported by the built-in DHCP server.
2112 @item dhcpstart=@var{addr}
2113 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
2114 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
2116 @item dns=@var{addr}
2117 Specify the guest-visible address of the virtual nameserver. The address must
2118 be different from the host address. Default is the 3rd IP in the guest network,
2121 @item ipv6-dns=@var{addr}
2122 Specify the guest-visible address of the IPv6 virtual nameserver. The address
2123 must be different from the host address. Default is the 3rd IP in the guest
2124 network, i.e. xxxx::3.
2126 @item dnssearch=@var{domain}
2127 Provides an entry for the domain-search list sent by the built-in
2128 DHCP server. More than one domain suffix can be transmitted by specifying
2129 this option multiple times. If supported, this will cause the guest to
2130 automatically try to append the given domain suffix(es) in case a domain name
2131 can not be resolved.
2135 qemu-system-i386 -nic user,dnssearch=mgmt.example.org,dnssearch=example.org
2138 @item domainname=@var{domain}
2139 Specifies the client domain name reported by the built-in DHCP server.
2141 @item tftp=@var{dir}
2142 When using the user mode network stack, activate a built-in TFTP
2143 server. The files in @var{dir} will be exposed as the root of a TFTP server.
2144 The TFTP client on the guest must be configured in binary mode (use the command
2145 @code{bin} of the Unix TFTP client).
2147 @item bootfile=@var{file}
2148 When using the user mode network stack, broadcast @var{file} as the BOOTP
2149 filename. In conjunction with @option{tftp}, this can be used to network boot
2150 a guest from a local directory.
2152 Example (using pxelinux):
2154 qemu-system-i386 -hda linux.img -boot n -device e1000,netdev=n1 \
2155 -netdev user,id=n1,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
2158 @item smb=@var{dir}[,smbserver=@var{addr}]
2159 When using the user mode network stack, activate a built-in SMB
2160 server so that Windows OSes can access to the host files in @file{@var{dir}}
2161 transparently. The IP address of the SMB server can be set to @var{addr}. By
2162 default the 4th IP in the guest network is used, i.e. x.x.x.4.
2164 In the guest Windows OS, the line:
2168 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
2169 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
2171 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
2173 Note that a SAMBA server must be installed on the host OS.
2175 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
2176 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
2177 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
2178 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
2179 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
2180 be bound to a specific host interface. If no connection type is set, TCP is
2181 used. This option can be given multiple times.
2183 For example, to redirect host X11 connection from screen 1 to guest
2184 screen 0, use the following:
2188 qemu-system-i386 -nic user,hostfwd=tcp:127.0.0.1:6001-:6000
2189 # this host xterm should open in the guest X11 server
2193 To redirect telnet connections from host port 5555 to telnet port on
2194 the guest, use the following:
2198 qemu-system-i386 -nic user,hostfwd=tcp::5555-:23
2199 telnet localhost 5555
2202 Then when you use on the host @code{telnet localhost 5555}, you
2203 connect to the guest telnet server.
2205 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
2206 @itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
2207 Forward guest TCP connections to the IP address @var{server} on port @var{port}
2208 to the character device @var{dev} or to a program executed by @var{cmd:command}
2209 which gets spawned for each connection. This option can be given multiple times.
2211 You can either use a chardev directly and have that one used throughout QEMU's
2212 lifetime
, like
in the following example
:
2215 # open
10.10.1.1:4321 on bootup
, connect
10.0.2.100:1234 to it whenever
2216 # the guest accesses it
2217 qemu
-system
-i386
-nic user
,guestfwd
=tcp
:10.0.2.100:1234-tcp
:10.10.1.1:4321
2220 Or you can execute a command on every TCP connection established by the guest
,
2221 so that QEMU behaves similar to an inetd process
for that virtual server
:
2224 # call
"netcat 10.10.1.1 4321" on every TCP connection to
10.0.2.100:1234
2225 # and connect the TCP stream to its stdin
/stdout
2226 qemu
-system
-i386
-nic
'user,id=n1,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
2231 Note
: Legacy stand
-alone options
-tftp
, -bootp
, -smb and
-redir are still
2232 processed and applied to
-net user
. Mixing them with the
new configuration
2233 syntax gives undefined results
. Their use
for new applications is discouraged
2234 as they will be removed from future versions
.
2236 @item
-netdev tap
,id
=@
var{id
}[,fd
=@
var{h
}][,ifname
=@
var{name
}][,script
=@
var{file
}][,downscript
=@
var{dfile
}][,br
=@
var{bridge
}][,helper
=@
var{helper
}]
2237 Configure a host TAP network backend with ID @
var{id
}.
2239 Use the network script @
var{file
} to configure it and the network script
2240 @
var{dfile
} to deconfigure it
. If @
var{name
} is not provided
, the OS
2241 automatically provides one
. The
default network configure script is
2242 @file
{/etc
/qemu
-ifup
} and the
default network deconfigure script is
2243 @file
{/etc
/qemu
-ifdown
}. Use @option
{script
=no
} or @option
{downscript
=no
}
2244 to disable script execution
.
2246 If running QEMU as an unprivileged user
, use the network helper
2247 @
var{helper
} to configure the TAP
interface and attach it to the bridge
.
2248 The
default network helper executable is @file
{/path
/to
/qemu
-bridge
-helper
}
2249 and the
default bridge device is @file
{br0
}.
2251 @option
{fd
}=@
var{h
} can be used to specify the handle of an already
2252 opened host TAP
interface.
2257 #launch a QEMU instance with the
default network script
2258 qemu
-system
-i386 linux
.img
-nic tap
2262 #launch a QEMU instance with two NICs
, each one connected
2264 qemu
-system
-i386 linux
.img \
2265 -netdev tap
,id
=nd0
,ifname
=tap0
-device e1000
,netdev
=nd0 \
2266 -netdev tap
,id
=nd1
,ifname
=tap1
-device rtl8139
,netdev
=nd1
2270 #launch a QEMU instance with the
default network helper to
2271 #connect a TAP device to bridge br0
2272 qemu
-system
-i386 linux
.img
-device virtio
-net
-pci
,netdev
=n1 \
2273 -netdev tap
,id
=n1
,"helper=/path/to/qemu-bridge-helper"
2276 @item
-netdev bridge
,id
=@
var{id
}[,br
=@
var{bridge
}][,helper
=@
var{helper
}]
2277 Connect a host TAP network
interface to a host bridge device
.
2279 Use the network helper @
var{helper
} to configure the TAP
interface and
2280 attach it to the bridge
. The
default network helper executable is
2281 @file
{/path
/to
/qemu
-bridge
-helper
} and the
default bridge
2282 device is @file
{br0
}.
2287 #launch a QEMU instance with the
default network helper to
2288 #connect a TAP device to bridge br0
2289 qemu
-system
-i386 linux
.img
-netdev bridge
,id
=n1
-device virtio
-net
,netdev
=n1
2293 #launch a QEMU instance with the
default network helper to
2294 #connect a TAP device to bridge qemubr0
2295 qemu
-system
-i386 linux
.img
-netdev bridge
,br
=qemubr0
,id
=n1
-device virtio
-net
,netdev
=n1
2298 @item
-netdev socket
,id
=@
var{id
}[,fd
=@
var{h
}][,listen
=[@
var{host
}]:@
var{port
}][,connect
=@
var{host
}:@
var{port
}]
2300 This host network backend can be used to connect the guest
's network to
2301 another QEMU virtual machine using a TCP socket connection. If @option{listen}
2302 is specified, QEMU waits for incoming connections on @var{port}
2303 (@var{host} is optional). @option{connect} is used to connect to
2304 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
2305 specifies an already opened TCP socket.
2309 # launch a first QEMU instance
2310 qemu-system-i386 linux.img \
2311 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \
2312 -netdev socket,id=n1,listen=:1234
2313 # connect the network of this instance to the network of the first instance
2314 qemu-system-i386 linux.img \
2315 -device e1000,netdev=n2,mac=52:54:00:12:34:57 \
2316 -netdev socket,id=n2,connect=127.0.0.1:1234
2319 @item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
2321 Configure a socket host network backend to share the guest's network traffic
2322 with another QEMU virtual machines
using a UDP multicast socket
, effectively
2323 making a bus
for every QEMU with same multicast address @
var{maddr
} and @
var{port
}.
2327 Several QEMU can be running on different hosts and share same
bus (assuming
2328 correct multicast setup
for these hosts
).
2330 mcast support is compatible with User Mode
Linux (argument @option
{eth@
var{N
}=mcast
}), see
2331 @url
{http
://user-mode-linux.sf.net}.
2333 Use @option
{fd
=h
} to specify an already opened UDP multicast socket
.
2338 # launch one QEMU instance
2339 qemu
-system
-i386 linux
.img \
2340 -device e1000
,netdev
=n1
,mac
=52:54:00:12:34:56 \
2341 -netdev socket
,id
=n1
,mcast
=230.0.0.1:1234
2342 # launch another QEMU instance on same
"bus"
2343 qemu
-system
-i386 linux
.img \
2344 -device e1000
,netdev
=n2
,mac
=52:54:00:12:34:57 \
2345 -netdev socket
,id
=n2
,mcast
=230.0.0.1:1234
2346 # launch yet another QEMU instance on same
"bus"
2347 qemu
-system
-i386 linux
.img \
2348 -device e1000
,netdev
=n3
,macaddr
=52:54:00:12:34:58 \
2349 -netdev socket
,id
=n3
,mcast
=230.0.0.1:1234
2352 Example (User Mode Linux compat
.):
2354 # launch QEMU
instance (note mcast address selected is UML
's default)
2355 qemu-system-i386 linux.img \
2356 -device e1000,netdev=n1,mac=52:54:00:12:34:56 \
2357 -netdev socket,id=n1,mcast=239.192.168.1:1102
2359 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
2362 Example (send packets from host's
1.2.3.4):
2364 qemu
-system
-i386 linux
.img \
2365 -device e1000
,netdev
=n1
,mac
=52:54:00:12:34:56 \
2366 -netdev socket
,id
=n1
,mcast
=239.192.168.1:1102,localaddr
=1.2.3.4
2369 @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
}]
2370 Configure a L2TPv3 pseudowire host network backend
. L2TPv3 (RFC3391
) is a
2371 popular protocol to transport
Ethernet (and other Layer
2) data frames between
2372 two systems
. It is present
in routers
, firewalls and the Linux kernel
2373 (from version
3.3 onwards
).
2375 This transport allows a VM to communicate to another VM
, router or firewall directly
.
2378 @item src
=@
var{srcaddr
}
2379 source
address (mandatory
)
2380 @item dst
=@
var{dstaddr
}
2381 destination
address (mandatory
)
2383 select udp
encapsulation (default is ip
).
2384 @item srcport
=@
var{srcport
}
2386 @item dstport
=@
var{dstport
}
2387 destination udp port
.
2389 force v6
, otherwise defaults to v4
.
2390 @item rxcookie
=@
var{rxcookie
}
2391 @itemx txcookie
=@
var{txcookie
}
2392 Cookies are a weak form of security
in the l2tpv3 specification
.
2393 Their
function is mostly to prevent misconfiguration
. By
default they are
32
2396 Set cookie size to
64 bit instead of the
default 32
2398 Force a
'cut-down' L2TPv3 with no counter as
in
2399 draft
-mkonstan
-l2tpext
-keyed
-ipv6
-tunnel
-00
2401 Work around broken counter handling
in peer
. This may also help on
2402 networks which have packet reorder
.
2403 @item offset
=@
var{offset
}
2404 Add an extra offset between header and data
2407 For example
, to attach a VM running on host
4.3.2.1 via L2TPv3 to the bridge br
-lan
2408 on the remote Linux host
1.2.3.4:
2410 # Setup tunnel on linux host
using raw ip as encapsulation
2412 ip l2tp add tunnel remote
4.3.2.1 local
1.2.3.4 tunnel_id
1 peer_tunnel_id
1 \
2413 encap udp udp_sport
16384 udp_dport
16384
2414 ip l2tp add session tunnel_id
1 name vmtunnel0 session_id \
2415 0xFFFFFFFF peer_session_id
0xFFFFFFFF
2416 ifconfig vmtunnel0 mtu
1500
2417 ifconfig vmtunnel0 up
2418 brctl addif br
-lan vmtunnel0
2422 # launch QEMU instance
- if your network has reorder or is very lossy add
,pincounter
2424 qemu
-system
-i386 linux
.img
-device e1000
,netdev
=n1 \
2425 -netdev l2tpv3
,id
=n1
,src
=4.2.3.1,dst
=1.2.3.4,udp
,srcport
=16384,dstport
=16384,rxsession
=0xffffffff,txsession
=0xffffffff,counter
2429 @item
-netdev vde
,id
=@
var{id
}[,sock
=@
var{socketpath
}][,port
=@
var{n
}][,group
=@
var{groupname
}][,mode
=@
var{octalmode
}]
2430 Configure VDE backend to connect to PORT @
var{n
} of a vde
switch running on host and
2431 listening
for incoming connections on @
var{socketpath
}. Use GROUP @
var{groupname
}
2432 and MODE @
var{octalmode
} to change
default ownership and permissions
for
2433 communication port
. This option is only available
if QEMU has been compiled
2434 with vde support enabled
.
2439 vde_switch
-F
-sock
/tmp
/myswitch
2440 # launch QEMU instance
2441 qemu
-system
-i386 linux
.img
-nic vde
,sock
=/tmp
/myswitch
2444 @item
-netdev vhost
-user
,chardev
=@
var{id
}[,vhostforce
=on|off
][,queues
=n
]
2446 Establish a vhost
-user netdev
, backed by a chardev @
var{id
}. The chardev should
2447 be a unix domain socket backed one
. The vhost
-user uses a specifically defined
2448 protocol to pass vhost ioctl replacement messages to an application on the other
2449 end of the socket
. On non
-MSIX guests
, the feature can be forced with
2450 @
var{vhostforce
}. Use
'queues=@var{n}' to specify the number of queues to
2451 be created
for multiqueue vhost
-user
.
2455 qemu
-m
512 -object memory
-backend
-file
,id
=mem
,size
=512M
,mem
-path
=/hugetlbfs
,share
=on \
2456 -numa node
,memdev
=mem \
2457 -chardev socket
,id
=chr0
,path
=/path
/to
/socket \
2458 -netdev type
=vhost
-user
,id
=net0
,chardev
=chr0 \
2459 -device virtio
-net
-pci
,netdev
=net0
2462 @item
-netdev hubport
,id
=@
var{id
},hubid
=@
var{hubid
}[,netdev
=@
var{nd
}]
2464 Create a hub port on the emulated hub with ID @
var{hubid
}.
2466 The hubport netdev lets you connect a NIC to a QEMU emulated hub instead of a
2467 single netdev
. Alternatively
, you can also connect the hubport to another
2468 netdev with ID @
var{nd
} by
using the @option
{netdev
=@
var{nd
}} option
.
2470 @item
-net nic
[,netdev
=@
var{nd
}][,macaddr
=@
var{mac
}][,model
=@
var{type
}] [,name
=@
var{name
}][,addr
=@
var{addr
}][,vectors
=@
var{v
}]
2472 Legacy option to configure or create an on
-board (or machine
default) Network
2473 Interface
Card(NIC
) and connect it either to the emulated hub with ID
0 (i
.e
.
2474 the
default hub
), or to the netdev @
var{nd
}.
2475 The NIC is an e1000 by
default on the PC target
. Optionally
, the MAC address
2476 can be changed to @
var{mac
}, the device address set to @
var{addr
} (PCI cards
2477 only
), and a @
var{name
} can be assigned
for use
in monitor commands
.
2478 Optionally
, for PCI cards
, you can specify the number @
var{v
} of MSI
-X vectors
2479 that the card should have
; this option currently only affects virtio cards
; set
2480 @
var{v
} = 0 to disable MSI
-X
. If no @option
{-net
} option is specified
, a single
2481 NIC is created
. QEMU can emulate several different models of network card
.
2482 Use @code
{-net nic
,model
=help
} for a list of available devices
for your target
.
2484 @item
-net user|tap|bridge|socket|l2tpv3|vde
[,...][,name
=@
var{name
}]
2485 Configure a host network
backend (with the options corresponding to the same
2486 @option
{-netdev
} option
) and connect it to the emulated hub
0 (the
default
2487 hub
). Use @
var{name
} to specify the name of the hub port
.
2495 DEFHEADING(Character device options
:)
2497 DEF("chardev", HAS_ARG
, QEMU_OPTION_chardev
,
2499 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2500 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
2501 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n"
2502 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n"
2503 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n"
2504 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n"
2505 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
2506 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
2507 " [,logfile=PATH][,logappend=on|off]\n"
2508 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2509 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
2510 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2511 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n"
2512 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2513 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2515 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2516 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2518 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2519 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n"
2521 #ifdef CONFIG_BRLAPI
2522 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2524 #
if defined(__linux__
) ||
defined(__sun__
) ||
defined(__FreeBSD__
) \
2525 ||
defined(__NetBSD__
) ||
defined(__OpenBSD__
) ||
defined(__DragonFly__
)
2526 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2527 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2529 #
if defined(__linux__
) ||
defined(__FreeBSD__
) ||
defined(__DragonFly__
)
2530 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2531 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2533 #
if defined(CONFIG_SPICE
)
2534 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2535 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2542 The general form of a character device option is
:
2544 @item
-chardev @
var{backend
},id
=@
var{id
}[,mux
=on|off
][,@
var{options
}]
2565 The specific backend will determine the applicable options
.
2567 Use @code
{-chardev help
} to print all available chardev backend types
.
2569 All devices must have an id
, which can be any string up to
127 characters long
.
2570 It is used to uniquely identify
this device
in other command line directives
.
2572 A character device may be used
in multiplexing mode by multiple front
-ends
.
2573 Specify @option
{mux
=on
} to enable
this mode
.
2574 A multiplexer is a
"1:N" device
, and
here the
"1" end is your specified chardev
2575 backend
, and the
"N" end is the various parts of QEMU that can talk to a chardev
.
2576 If you create a chardev with @option
{id
=myid
} and @option
{mux
=on
}, QEMU will
2577 create a multiplexer with your specified ID
, and you can then configure multiple
2578 front ends to use that chardev ID
for their input
/output
. Up to four different
2579 front ends can be connected to a single multiplexed chardev
. (Without
2580 multiplexing enabled
, a chardev can only be used by a single front end
.)
2581 For instance you could use
this to allow a single stdio chardev to be used by
2582 two serial ports and the QEMU monitor
:
2585 -chardev stdio
,mux
=on
,id
=char0 \
2586 -mon chardev
=char0
,mode
=readline \
2587 -serial chardev
:char0 \
2588 -serial chardev
:char0
2591 You can have more than one multiplexer
in a system configuration
; for instance
2592 you could have a TCP port multiplexed between UART
0 and UART
1, and stdio
2593 multiplexed between the QEMU monitor and a parallel port
:
2596 -chardev stdio
,mux
=on
,id
=char0 \
2597 -mon chardev
=char0
,mode
=readline \
2598 -parallel chardev
:char0 \
2599 -chardev tcp
,...,mux
=on
,id
=char1 \
2600 -serial chardev
:char1 \
2601 -serial chardev
:char1
2604 When you
're using a multiplexed character device, some escape sequences are
2605 interpreted in the input. @xref{mux_keys, Keys in the character backend
2608 Note that some other command line options may implicitly create multiplexed
2609 character backends; for instance @option{-serial mon:stdio} creates a
2610 multiplexed stdio backend connected to the serial port and the QEMU monitor,
2611 and @option{-nographic} also multiplexes the console and the monitor to
2614 There is currently no support for multiplexing in the other direction
2615 (where a single QEMU front end takes input and output from multiple chardevs).
2617 Every backend supports the @option{logfile} option, which supplies the path
2618 to a file to record all data transmitted via the backend. The @option{logappend}
2619 option controls whether the log file will be truncated or appended to when
2624 The available backends are:
2627 @item -chardev null,id=@var{id}
2628 A void device. This device will not emit any data, and will drop any data it
2629 receives. The null backend does not take any options.
2631 @item -chardev socket,id=@var{id}[,@var{TCP options} or @var{unix options}][,server][,nowait][,telnet][,reconnect=@var{seconds}][,tls-creds=@var{id}]
2633 Create a two-way stream socket, which can be either a TCP or a unix socket. A
2634 unix socket will be created if @option{path} is specified. Behaviour is
2635 undefined if TCP options are specified for a unix socket.
2637 @option{server} specifies that the socket shall be a listening socket.
2639 @option{nowait} specifies that QEMU should not block waiting for a client to
2640 connect to a listening socket.
2642 @option{telnet} specifies that traffic on the socket should interpret telnet
2645 @option{reconnect} sets the timeout for reconnecting on non-server sockets when
2646 the remote end goes away. qemu will delay this many seconds and then attempt
2647 to reconnect. Zero disables reconnecting, and is the default.
2649 @option{tls-creds} requests enablement of the TLS protocol for encryption,
2650 and specifies the id of the TLS credentials to use for the handshake. The
2651 credentials must be previously created with the @option{-object tls-creds}
2654 TCP and unix socket options are given below:
2658 @item TCP options: port=@var{port}[,host=@var{host}][,to=@var{to}][,ipv4][,ipv6][,nodelay]
2660 @option{host} for a listening socket specifies the local address to be bound.
2661 For a connecting socket species the remote host to connect to. @option{host} is
2662 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
2664 @option{port} for a listening socket specifies the local port to be bound. For a
2665 connecting socket specifies the port on the remote host to connect to.
2666 @option{port} can be given as either a port number or a service name.
2667 @option{port} is required.
2669 @option{to} is only relevant to listening sockets. If it is specified, and
2670 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
2671 to and including @option{to} until it succeeds. @option{to} must be specified
2674 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2675 If neither is specified the socket may use either protocol.
2677 @option{nodelay} disables the Nagle algorithm.
2679 @item unix options: path=@var{path}
2681 @option{path} specifies the local path of the unix socket. @option{path} is
2686 @item -chardev udp,id=@var{id}[,host=@var{host}],port=@var{port}[,localaddr=@var{localaddr}][,localport=@var{localport}][,ipv4][,ipv6]
2688 Sends all traffic from the guest to a remote host over UDP.
2690 @option{host} specifies the remote host to connect to. If not specified it
2691 defaults to @code{localhost}.
2693 @option{port} specifies the port on the remote host to connect to. @option{port}
2696 @option{localaddr} specifies the local address to bind to. If not specified it
2697 defaults to @code{0.0.0.0}.
2699 @option{localport} specifies the local port to bind to. If not specified any
2700 available local port will be used.
2702 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2703 If neither is specified the device may use either protocol.
2705 @item -chardev msmouse,id=@var{id}
2707 Forward QEMU's emulated msmouse events to the guest
. @option
{msmouse
} does not
2710 @item
-chardev vc
,id
=@
var{id
}[[,width
=@
var{width
}][,height
=@
var{height
}]][[,cols
=@
var{cols
}][,rows
=@
var{rows
}]]
2712 Connect to a QEMU text console
. @option
{vc
} may optionally be given a specific
2715 @option
{width
} and @option
{height
} specify the width and height respectively of
2716 the console
, in pixels
.
2718 @option
{cols
} and @option
{rows
} specify that the console be sized to fit a text
2719 console with the given dimensions
.
2721 @item
-chardev ringbuf
,id
=@
var{id
}[,size
=@
var{size
}]
2723 Create a ring buffer with fixed size @option
{size
}.
2724 @
var{size
} must be a power of two and defaults to @code
{64K
}.
2726 @item
-chardev file
,id
=@
var{id
},path
=@
var{path
}
2728 Log all traffic received from the guest to a file
.
2730 @option
{path
} specifies the path of the file to be opened
. This file will be
2731 created
if it does not already exist
, and overwritten
if it does
. @option
{path
}
2734 @item
-chardev pipe
,id
=@
var{id
},path
=@
var{path
}
2736 Create a two
-way connection to the guest
. The behaviour differs slightly between
2737 Windows hosts and other hosts
:
2739 On Windows
, a single duplex pipe will be created at
2740 @file
{\\.pipe\@option
{path
}}.
2742 On other hosts
, 2 pipes will be created called @file
{@option
{path
}.in} and
2743 @file
{@option
{path
}.out
}. Data written to @file
{@option
{path
}.in} will be
2744 received by the guest
. Data written by the guest can be read from
2745 @file
{@option
{path
}.out
}. QEMU will not create these fifos
, and requires them to
2748 @option
{path
} forms part of the pipe path as described above
. @option
{path
} is
2751 @item
-chardev console
,id
=@
var{id
}
2753 Send traffic from the guest to QEMU
's standard output. @option{console} does not
2756 @option{console} is only available on Windows hosts.
2758 @item -chardev serial,id=@var{id},path=@option{path}
2760 Send traffic from the guest to a serial device on the host.
2762 On Unix hosts serial will actually accept any tty device,
2763 not only serial lines.
2765 @option{path} specifies the name of the serial device to open.
2767 @item -chardev pty,id=@var{id}
2769 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2770 not take any options.
2772 @option{pty} is not available on Windows hosts.
2774 @item -chardev stdio,id=@var{id}[,signal=on|off]
2775 Connect to standard input and standard output of the QEMU process.
2777 @option{signal} controls if signals are enabled on the terminal, that includes
2778 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2779 default, use @option{signal=off} to disable it.
2781 @item -chardev braille,id=@var{id}
2783 Connect to a local BrlAPI server. @option{braille} does not take any options.
2785 @item -chardev tty,id=@var{id},path=@var{path}
2787 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2788 DragonFlyBSD hosts. It is an alias for @option{serial}.
2790 @option{path} specifies the path to the tty. @option{path} is required.
2792 @item -chardev parallel,id=@var{id},path=@var{path}
2793 @itemx -chardev parport,id=@var{id},path=@var{path}
2795 @option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2797 Connect to a local parallel port.
2799 @option{path} specifies the path to the parallel port device. @option{path} is
2802 @item -chardev spicevmc,id=@var{id},debug=@var{debug},name=@var{name}
2804 @option{spicevmc} is only available when spice support is built in.
2806 @option{debug} debug level for spicevmc
2808 @option{name} name of spice channel to connect to
2810 Connect to a spice virtual machine channel, such as vdiport.
2812 @item -chardev spiceport,id=@var{id},debug=@var{debug},name=@var{name}
2814 @option{spiceport} is only available when spice support is built in.
2816 @option{debug} debug level for spicevmc
2818 @option{name} name of spice port to connect to
2820 Connect to a spice port, allowing a Spice client to handle the traffic
2821 identified by a name (preferably a fqdn).
2829 DEFHEADING(Bluetooth(R) options:)
2834 DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
2835 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands
\n" \
2836 "-bt hci
,host
[:id
]\n" \
2837 " use host
's HCI with the given name\n" \
2838 "-bt hci[,vlan=n]\n" \
2839 " emulate a standard HCI in virtual scatternet 'n
'\n" \
2840 "-bt vhci[,vlan=n]\n" \
2841 " add host computer to virtual scatternet 'n
' using VHCI\n" \
2842 "-bt device:dev[,vlan=n]\n" \
2843 " emulate a bluetooth device 'dev
' in scatternet 'n
'\n",
2848 Defines the function of the corresponding Bluetooth HCI. -bt options
2849 are matched with the HCIs present in the chosen machine type. For
2850 example when emulating a machine with only one HCI built into it, only
2851 the first @code{-bt hci[...]} option is valid and defines the HCI's
2852 logic
. The Transport Layer is decided by the machine type
. Currently
2853 the machines @code
{n800
} and @code
{n810
} have one HCI and all other
2857 The following three types are recognized
:
2861 (default) The corresponding Bluetooth HCI assumes no internal logic
2862 and will not respond to any HCI commands or emit events
.
2864 @item
-bt hci
,host
[:@
var{id
}]
2865 (@code
{bluez
} only
) The corresponding HCI passes commands
/ events
2866 to
/ from the physical HCI identified by the name @
var{id
} (default:
2867 @code
{hci0
}) on the computer running QEMU
. Only available on @code
{bluez
}
2868 capable systems like Linux
.
2870 @item
-bt hci
[,vlan
=@
var{n
}]
2871 Add a virtual
, standard HCI that will participate
in the Bluetooth
2872 scatternet @
var{n
} (default @code
{0}). Similarly to @option
{-net
}
2873 VLANs
, devices inside a bluetooth network @
var{n
} can only communicate
2874 with other devices
in the same
network (scatternet
).
2877 @item
-bt vhci
[,vlan
=@
var{n
}]
2878 (Linux
-host only
) Create a HCI
in scatternet @
var{n
} (default 0) attached
2879 to the host bluetooth stack instead of to the emulated target
. This
2880 allows the host and target machines to participate
in a common scatternet
2881 and communicate
. Requires the Linux @code
{vhci
} driver installed
. Can
2882 be used as following
:
2885 qemu
-system
-i386
[...OPTIONS
...] -bt hci
,vlan
=5 -bt vhci
,vlan
=5
2888 @item
-bt device
:@
var{dev
}[,vlan
=@
var{n
}]
2889 Emulate a bluetooth device @
var{dev
} and place it
in network @
var{n
}
2890 (default @code
{0}). QEMU can only emulate one type of bluetooth devices
2895 Virtual wireless keyboard implementing the HIDP bluetooth profile
.
2905 DEFHEADING(TPM device options
:)
2907 DEF("tpmdev", HAS_ARG
, QEMU_OPTION_tpmdev
, \
2908 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
2909 " use path to provide path to a character device; default is /dev/tpm0\n"
2910 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
2911 " not provided it will be searched for in /sys/class/misc/tpm?/device\n"
2912 "-tpmdev emulator,id=id,chardev=dev\n"
2913 " configure the TPM device using chardev backend\n",
2917 The general form of a TPM device option is
:
2920 @item
-tpmdev @
var{backend
},id
=@
var{id
}[,@
var{options
}]
2923 The specific backend type will determine the applicable options
.
2924 The @code
{-tpmdev
} option creates the TPM backend and requires a
2925 @code
{-device
} option that specifies the TPM frontend
interface model
.
2927 Use @code
{-tpmdev help
} to print all available TPM backend types
.
2931 The available backends are
:
2935 @item
-tpmdev passthrough
,id
=@
var{id
},path
=@
var{path
},cancel
-path
=@
var{cancel
-path
}
2937 (Linux
-host only
) Enable access to the host
's TPM using the passthrough
2940 @option{path} specifies the path to the host's TPM device
, i
.e
., on
2941 a Linux host
this would be @code
{/dev
/tpm0
}.
2942 @option
{path
} is optional and by
default @code
{/dev
/tpm0
} is used
.
2944 @option
{cancel
-path
} specifies the path to the host TPM device
's sysfs
2945 entry allowing for cancellation of an ongoing TPM command.
2946 @option{cancel-path} is optional and by default QEMU will search for the
2949 Some notes about using the host's TPM with the passthrough driver
:
2951 The TPM device accessed by the passthrough driver must not be
2952 used by any other application on the host
.
2954 Since the host
's firmware (BIOS/UEFI) has already initialized the TPM,
2955 the VM's
firmware (BIOS
/UEFI
) will not be able to initialize the
2956 TPM again and may therefore not show a TPM
-specific menu that would
2957 otherwise allow the user to configure the TPM
, e
.g
., allow the user to
2958 enable
/disable or activate
/deactivate the TPM
.
2959 Further
, if TPM ownership is released from within a VM then the host
's TPM
2960 will get disabled and deactivated. To enable and activate the
2961 TPM again afterwards, the host has to be rebooted and the user is
2962 required to enter the firmware's menu to enable and activate the TPM
.
2963 If the TPM is left disabled and
/or deactivated most TPM commands will fail
.
2965 To create a passthrough TPM use the following two options
:
2967 -tpmdev passthrough
,id
=tpm0
-device tpm
-tis
,tpmdev
=tpm0
2969 Note that the @code
{-tpmdev
} id is @code
{tpm0
} and is referenced by
2970 @code
{tpmdev
=tpm0
} in the device option
.
2972 @item
-tpmdev emulator
,id
=@
var{id
},chardev
=@
var{dev
}
2974 (Linux
-host only
) Enable access to a TPM emulator
using Unix domain socket based
2977 @option
{chardev
} specifies the unique ID of a character device backend that provides connection to the software TPM server
.
2979 To create a TPM emulator backend device with chardev socket backend
:
2982 -chardev socket
,id
=chrtpm
,path
=/tmp
/swtpm
-sock
-tpmdev emulator
,id
=tpm0
,chardev
=chrtpm
-device tpm
-tis
,tpmdev
=tpm0
2995 DEFHEADING(Linux
/Multiboot boot specific
:)
2998 When
using these options
, you can use a given Linux or Multiboot
2999 kernel without installing it
in the disk image
. It can be useful
3000 for easier testing of various kernels
.
3005 DEF("kernel", HAS_ARG
, QEMU_OPTION_kernel
, \
3006 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL
)
3008 @item
-kernel @
var{bzImage
}
3010 Use @
var{bzImage
} as kernel image
. The kernel can be either a Linux kernel
3011 or
in multiboot format
.
3014 DEF("append", HAS_ARG
, QEMU_OPTION_append
, \
3015 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL
)
3017 @item
-append @
var{cmdline
}
3019 Use @
var{cmdline
} as kernel command line
3022 DEF("initrd", HAS_ARG
, QEMU_OPTION_initrd
, \
3023 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL
)
3025 @item
-initrd @
var{file
}
3027 Use @
var{file
} as initial ram disk
.
3029 @item
-initrd
"@var{file1} arg=foo,@var{file2}"
3031 This syntax is only available with multiboot
.
3033 Use @
var{file1
} and @
var{file2
} as modules and pass arg
=foo as parameter to the
3037 DEF("dtb", HAS_ARG
, QEMU_OPTION_dtb
, \
3038 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL
)
3040 @item
-dtb @
var{file
}
3042 Use @
var{file
} as a device tree
binary (dtb
) image and pass it to the kernel
3051 DEFHEADING(Debug
/Expert options
:)
3056 DEF("fw_cfg", HAS_ARG
, QEMU_OPTION_fwcfg
,
3057 "-fw_cfg [name=]<name>,file=<file>\n"
3058 " add named fw_cfg entry with contents from file\n"
3059 "-fw_cfg [name=]<name>,string=<str>\n"
3060 " add named fw_cfg entry with contents from string\n",
3064 @item
-fw_cfg
[name
=]@
var{name
},file
=@
var{file
}
3066 Add named fw_cfg entry with contents from file @
var{file
}.
3068 @item
-fw_cfg
[name
=]@
var{name
},string
=@
var{str
}
3069 Add named fw_cfg entry with contents from string @
var{str
}.
3071 The terminating NUL character of the contents of @
var{str
} will not be
3072 included as part of the fw_cfg item data
. To insert contents with
3073 embedded NUL characters
, you have to use the @
var{file
} parameter
.
3075 The fw_cfg entries are passed by QEMU through to the guest
.
3079 -fw_cfg name
=opt
/com
.mycompany
/blob
,file
=./my_blob
.bin
3081 creates an fw_cfg entry named opt
/com
.mycompany
/blob with contents
3086 DEF("serial", HAS_ARG
, QEMU_OPTION_serial
, \
3087 "-serial dev redirect the serial port to char device 'dev'\n",
3090 @item
-serial @
var{dev
}
3092 Redirect the virtual serial port to host character device
3093 @
var{dev
}. The
default device is @code
{vc
} in graphical mode and
3094 @code
{stdio
} in non graphical mode
.
3096 This option can be used several times to simulate up to
4 serial
3099 Use @code
{-serial none
} to disable all serial ports
.
3101 Available character devices are
:
3103 @item vc
[:@
var{W
}x@
var{H
}]
3104 Virtual console
. Optionally
, a width and height can be given
in pixel with
3108 It is also possible to specify width or height
in characters
:
3113 [Linux only
] Pseudo
TTY (a
new PTY is automatically allocated
)
3115 No device is allocated
.
3118 @item chardev
:@
var{id
}
3119 Use a named character device defined with the @code
{-chardev
} option
.
3121 [Linux only
] Use host tty
, e
.g
. @file
{/dev
/ttyS0
}. The host serial port
3122 parameters are set according to the emulated ones
.
3123 @item
/dev
/parport@
var{N
}
3124 [Linux only
, parallel port only
] Use host parallel port
3125 @
var{N
}. Currently SPP and EPP parallel port features can be used
.
3126 @item file
:@
var{filename
}
3127 Write output to @
var{filename
}. No character can be read
.
3129 [Unix only
] standard input
/output
3130 @item pipe
:@
var{filename
}
3131 name pipe @
var{filename
}
3133 [Windows only
] Use host serial port @
var{n
}
3134 @item udp
:[@
var{remote_host
}]:@
var{remote_port
}[@@
[@
var{src_ip
}]:@
var{src_port
}]
3135 This
implements UDP Net Console
.
3136 When @
var{remote_host
} or @
var{src_ip
} are not specified
3137 they
default to @code
{0.0.0.0}.
3138 When not
using a specified @
var{src_port
} a random port is automatically chosen
.
3140 If you just want a simple readonly console you can use @code
{netcat
} or
3141 @code
{nc
}, by starting QEMU with
: @code
{-serial udp
::4555} and nc as
:
3142 @code
{nc
-u
-l
-p
4555}. Any time QEMU writes something to that port it
3143 will appear
in the netconsole session
.
3145 If you plan to send characters back via netconsole or you want to stop
3146 and start QEMU a lot of times
, you should have QEMU use the same
3147 source port each time by
using something like @code
{-serial
3148 udp
::4555@@
:4556} to QEMU
. Another approach is to use a patched
3149 version of netcat which can listen to a TCP port and send and receive
3150 characters via udp
. If you have a patched version of netcat which
3151 activates telnet remote echo and single char transfer
, then you can
3152 use the following options to set up a netcat redirector to allow
3153 telnet on port
5555 to access the QEMU port
.
3156 -serial udp
::4555@@
:4556
3157 @item netcat options
:
3158 -u
-P
4555 -L
0.0.0.0:4556 -t
-p
5555 -I
-T
3159 @item telnet options
:
3163 @item tcp
:[@
var{host
}]:@
var{port
}[,@
var{server
}][,nowait
][,nodelay
][,reconnect
=@
var{seconds
}]
3164 The TCP Net Console has two modes of operation
. It can send the serial
3165 I
/O to a location or wait
for a connection from a location
. By
default
3166 the TCP Net Console is sent to @
var{host
} at the @
var{port
}. If you use
3167 the @
var{server
} option QEMU will wait
for a client socket application
3168 to connect to the port before continuing
, unless the @code
{nowait
}
3169 option was specified
. The @code
{nodelay
} option disables the Nagle buffering
3170 algorithm
. The @code
{reconnect
} option only applies
if @
var{noserver
} is
3171 set
, if the connection goes down it will attempt to reconnect at the
3172 given interval
. If @
var{host
} is omitted
, 0.0.0.0 is assumed
. Only
3173 one TCP connection at a time is accepted
. You can use @code
{telnet
} to
3174 connect to the corresponding character device
.
3176 @item Example to send tcp console to
192.168.0.2 port
4444
3177 -serial tcp
:192.168.0.2:4444
3178 @item Example to listen and wait on port
4444 for connection
3179 -serial tcp
::4444,server
3180 @item Example to not wait and listen on ip
192.168.0.100 port
4444
3181 -serial tcp
:192.168.0.100:4444,server
,nowait
3184 @item telnet
:@
var{host
}:@
var{port
}[,server
][,nowait
][,nodelay
]
3185 The telnet protocol is used instead of raw tcp sockets
. The options
3186 work the same as
if you had specified @code
{-serial tcp
}. The
3187 difference is that the port acts like a telnet server or client
using
3188 telnet option negotiation
. This will also allow you to send the
3189 MAGIC_SYSRQ sequence
if you use a telnet that supports sending the
break
3190 sequence
. Typically
in unix telnet you
do it with Control
-] and then
3191 type
"send break" followed by pressing the enter key
.
3193 @item unix
:@
var{path
}[,server
][,nowait
][,reconnect
=@
var{seconds
}]
3194 A unix domain socket is used instead of a tcp socket
. The option works the
3195 same as
if you had specified @code
{-serial tcp
} except the unix domain socket
3196 @
var{path
} is used
for connections
.
3198 @item mon
:@
var{dev_string
}
3199 This is a special option to allow the monitor to be multiplexed onto
3200 another serial port
. The monitor is accessed with key sequence of
3201 @key
{Control
-a
} and then pressing @key
{c
}.
3202 @
var{dev_string
} should be any one of the serial devices specified
3203 above
. An example to multiplex the monitor onto a telnet server
3204 listening on port
4444 would be
:
3206 @item
-serial mon
:telnet
::4444,server
,nowait
3208 When the monitor is multiplexed to stdio
in this way
, Ctrl
+C will not terminate
3209 QEMU any more but will be passed to the guest instead
.
3212 Braille device
. This will use BrlAPI to display the braille output on a real
3216 Three button serial mouse
. Configure the guest to use Microsoft protocol
.
3220 DEF("parallel", HAS_ARG
, QEMU_OPTION_parallel
, \
3221 "-parallel dev redirect the parallel port to char device 'dev'\n",
3224 @item
-parallel @
var{dev
}
3226 Redirect the virtual parallel port to host device @
var{dev
} (same
3227 devices as the serial port
). On Linux hosts
, @file
{/dev
/parportN
} can
3228 be used to use hardware devices connected on the corresponding host
3231 This option can be used several times to simulate up to
3 parallel
3234 Use @code
{-parallel none
} to disable all parallel ports
.
3237 DEF("monitor", HAS_ARG
, QEMU_OPTION_monitor
, \
3238 "-monitor dev redirect the monitor to char device 'dev'\n",
3241 @item
-monitor @
var{dev
}
3243 Redirect the monitor to host device @
var{dev
} (same devices as the
3245 The
default device is @code
{vc
} in graphical mode and @code
{stdio
} in
3247 Use @code
{-monitor none
} to disable the
default monitor
.
3249 DEF("qmp", HAS_ARG
, QEMU_OPTION_qmp
, \
3250 "-qmp dev like -monitor but opens in 'control' mode\n",
3253 @item
-qmp @
var{dev
}
3255 Like
-monitor but opens
in 'control' mode
.
3257 DEF("qmp-pretty", HAS_ARG
, QEMU_OPTION_qmp_pretty
, \
3258 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n",
3261 @item
-qmp
-pretty @
var{dev
}
3263 Like
-qmp but uses pretty JSON formatting
.
3266 DEF("mon", HAS_ARG
, QEMU_OPTION_mon
, \
3267 "-mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]\n", QEMU_ARCH_ALL
)
3269 @item
-mon
[chardev
=]name
[,mode
=readline|control
][,pretty
[=on|off
]]
3271 Setup monitor on chardev @
var{name
}. @code
{pretty
} turns on JSON pretty printing
3272 easing human reading and debugging
.
3275 DEF("debugcon", HAS_ARG
, QEMU_OPTION_debugcon
, \
3276 "-debugcon dev redirect the debug console to char device 'dev'\n",
3279 @item
-debugcon @
var{dev
}
3281 Redirect the debug console to host device @
var{dev
} (same devices as the
3282 serial port
). The debug console is an I
/O port which is typically port
3283 0xe9; writing to that I
/O port sends output to
this device
.
3284 The
default device is @code
{vc
} in graphical mode and @code
{stdio
} in
3288 DEF("pidfile", HAS_ARG
, QEMU_OPTION_pidfile
, \
3289 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL
)
3291 @item
-pidfile @
var{file
}
3293 Store the QEMU process PID
in @
var{file
}. It is useful
if you launch QEMU
3297 DEF("singlestep", 0, QEMU_OPTION_singlestep
, \
3298 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL
)
3302 Run the emulation
in single step mode
.
3305 DEF("preconfig", 0, QEMU_OPTION_preconfig
, \
3306 "--preconfig pause QEMU before machine is initialized (experimental)\n",
3311 Pause QEMU
for interactive configuration before the machine is created
,
3312 which allows querying and configuring properties that will affect
3313 machine initialization
. Use QMP command
'x-exit-preconfig' to exit
3314 the preconfig state and move to the next
state (i
.e
. run guest
if -S
3315 isn
't used or pause the second time if -S is used). This option is
3319 DEF("S", 0, QEMU_OPTION_S, \
3320 "-S freeze CPU at startup (use 'c
' to start execution)\n",
3325 Do not start CPU at startup (you must type 'c
' in the monitor).
3328 DEF("realtime", HAS_ARG, QEMU_OPTION_realtime,
3329 "-realtime [mlock=on|off]\n"
3330 " run qemu with realtime features\n"
3331 " mlock=on|off controls mlock support (default: on)\n",
3334 @item -realtime mlock=on|off
3336 Run qemu with realtime features.
3337 mlocking qemu and guest memory can be enabled via @option{mlock=on}
3338 (enabled by default).
3341 DEF("overcommit", HAS_ARG, QEMU_OPTION_overcommit,
3342 "-overcommit [mem-lock=on|off][cpu-pm=on|off]\n"
3343 " run qemu with overcommit hints\n"
3344 " mem-lock=on|off controls memory lock support (default: off)\n"
3345 " cpu-pm=on|off controls cpu power management (default: off)\n",
3348 @item -overcommit mem-lock=on|off
3349 @item -overcommit cpu-pm=on|off
3351 Run qemu with hints about host resource overcommit. The default is
3352 to assume that host overcommits all resources.
3354 Locking qemu and guest memory can be enabled via @option{mem-lock=on} (disabled
3355 by default). This works when host memory is not overcommitted and reduces the
3356 worst-case latency for guest. This is equivalent to @option{realtime}.
3358 Guest ability to manage power state of host cpus (increasing latency for other
3359 processes on the same host cpu, but decreasing latency for guest) can be
3360 enabled via @option{cpu-pm=on} (disabled by default). This works best when
3361 host CPU is not overcommitted. When used, host estimates of CPU cycle and power
3362 utilization will be incorrect, not taking into account guest idle time.
3365 DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
3366 "-gdb dev wait for gdb connection on 'dev
'\n", QEMU_ARCH_ALL)
3368 @item -gdb @var{dev}
3370 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
3371 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
3372 stdio are reasonable use case. The latter is allowing to start QEMU from
3373 within gdb and establish the connection via a pipe:
3375 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
3379 DEF("s", 0, QEMU_OPTION_s, \
3380 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
3385 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
3386 (@pxref{gdb_usage}).
3389 DEF("d", HAS_ARG, QEMU_OPTION_d, \
3390 "-d item1,... enable logging of specified items (use '-d help
' for a list of log items)\n",
3393 @item -d @var{item1}[,...]
3395 Enable logging of specified items. Use '-d help
' for a list of log items.
3398 DEF("D", HAS_ARG, QEMU_OPTION_D, \
3399 "-D logfile output log to logfile (default stderr)\n",
3402 @item -D @var{logfile}
3404 Output log in @var{logfile} instead of to stderr
3407 DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \
3408 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n",
3411 @item -dfilter @var{range1}[,...]
3413 Filter debug output to that relevant to a range of target addresses. The filter
3414 spec can be either @var{start}+@var{size}, @var{start}-@var{size} or
3415 @var{start}..@var{end} where @var{start} @var{end} and @var{size} are the
3416 addresses and sizes required. For example:
3418 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000
3420 Will dump output for any code in the 0x1000 sized block starting at 0x8000 and
3421 the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized
3422 block starting at 0xffffffc00005f000.
3425 DEF("L", HAS_ARG, QEMU_OPTION_L, \
3426 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
3431 Set the directory for the BIOS, VGA BIOS and keymaps.
3433 To list all the data directories, use @code{-L help}.
3436 DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
3437 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL)
3439 @item -bios @var{file}
3441 Set the filename for the BIOS.
3444 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
3445 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL)
3449 Enable KVM full virtualization support. This option is only available
3450 if KVM support is enabled when compiling.
3453 DEF("enable-hax", 0, QEMU_OPTION_enable_hax, \
3454 "-enable-hax enable HAX virtualization support\n", QEMU_ARCH_I386)
3458 Enable HAX (Hardware-based Acceleration eXecution) support. This option
3459 is only available if HAX support is enabled when compiling. HAX is only
3460 applicable to MAC and Windows platform, and thus does not conflict with
3461 KVM. This option is deprecated, use @option{-accel hax} instead.
3464 DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
3465 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL)
3466 DEF("xen-create", 0, QEMU_OPTION_xen_create,
3467 "-xen-create create domain using xen hypercalls, bypassing xend\n"
3468 " warning: should not be used when xend is in use\n",
3470 DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
3471 "-xen-attach attach to existing xen domain\n"
3472 " xend will use this when starting QEMU\n",
3474 DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict,
3475 "-xen-domid-restrict restrict set of available xen operations\n"
3476 " to specified domain id. (Does not affect\n"
3477 " xenpv machine type).\n",
3480 @item -xen-domid @var{id}
3482 Specify xen guest domain @var{id} (XEN only).
3485 Create domain using xen hypercalls, bypassing xend.
3486 Warning: should not be used when xend is in use (XEN only).
3489 Attach to existing xen domain.
3490 xend will use this when starting QEMU (XEN only).
3491 @findex -xen-domid-restrict
3492 Restrict set of available xen operations to specified domain id (XEN only).
3495 DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
3496 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL)
3500 Exit instead of rebooting.
3503 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
3504 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL)
3507 @findex -no-shutdown
3508 Don't exit QEMU on guest shutdown
, but instead only stop the emulation
.
3509 This allows
for instance switching to monitor to commit changes to the
3513 DEF("loadvm", HAS_ARG
, QEMU_OPTION_loadvm
, \
3514 "-loadvm [tag|id]\n" \
3515 " start right away with a saved state (loadvm in monitor)\n",
3518 @item
-loadvm @
var{file
}
3520 Start right away with a saved
state (@code
{loadvm
} in monitor
)
3524 DEF("daemonize", 0, QEMU_OPTION_daemonize
, \
3525 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL
)
3530 Daemonize the QEMU process after initialization
. QEMU will not detach from
3531 standard IO until it is ready to receive connections on any of its devices
.
3532 This option is a useful way
for external programs to launch QEMU without having
3533 to cope with initialization race conditions
.
3536 DEF("option-rom", HAS_ARG
, QEMU_OPTION_option_rom
, \
3537 "-option-rom rom load a file, rom, into the option ROM space\n",
3540 @item
-option
-rom @
var{file
}
3542 Load the contents of @
var{file
} as an option ROM
.
3543 This option is useful to load things like EtherBoot
.
3546 HXCOMM Silently ignored
for compatibility
3547 DEF("clock", HAS_ARG
, QEMU_OPTION_clock
, "", QEMU_ARCH_ALL
)
3549 HXCOMM Options deprecated by
-rtc
3550 DEF("localtime", 0, QEMU_OPTION_localtime
, "", QEMU_ARCH_ALL
)
3551 DEF("startdate", HAS_ARG
, QEMU_OPTION_startdate
, "", QEMU_ARCH_ALL
)
3553 DEF("rtc", HAS_ARG
, QEMU_OPTION_rtc
, \
3554 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
3555 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
3560 @item
-rtc
[base
=utc|localtime|@
var{date
}][,clock
=host|vm
][,driftfix
=none|slew
]
3562 Specify @option
{base
} as @code
{utc
} or @code
{localtime
} to let the RTC start at the current
3563 UTC or local time
, respectively
. @code
{localtime
} is required
for correct date
in
3564 MS
-DOS or Windows
. To start at a specific point
in time
, provide @
var{date
} in the
3565 format @code
{2006-06-17T16
:01:21} or @code
{2006-06-17}. The
default base is UTC
.
3567 By
default the RTC is driven by the host system time
. This allows
using of the
3568 RTC as accurate reference clock inside the guest
, specifically
if the host
3569 time is smoothly following an accurate external reference clock
, e
.g
. via NTP
.
3570 If you want to isolate the guest time from the host
, you can set @option
{clock
}
3571 to @code
{rt
} instead
. To even prevent it from progressing during suspension
,
3572 you can set it to @code
{vm
}.
3574 Enable @option
{driftfix
} (i386 targets only
) if you experience time drift problems
,
3575 specifically with Windows
' ACPI HAL. This option will try to figure out how
3576 many timer interrupts were not processed by the Windows guest and will
3580 DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
3581 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \
3582 " enable virtual instruction counter with 2^N clock ticks per\n" \
3583 " instruction, enable aligning the host and virtual clocks\n" \
3584 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL)
3586 @item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}]
3588 Enable virtual instruction counter. The virtual cpu will execute one
3589 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
3590 then the virtual cpu speed will be automatically adjusted to keep virtual
3591 time within a few seconds of real time.
3593 When the virtual cpu is sleeping, the virtual time will advance at default
3594 speed unless @option{sleep=on|off} is specified.
3595 With @option{sleep=on|off}, the virtual time will jump to the next timer deadline
3596 instantly whenever the virtual cpu goes to sleep mode and will not advance
3597 if no timer is enabled. This behavior give deterministic execution times from
3598 the guest point of view.
3600 Note that while this option can give deterministic behavior, it does not
3601 provide cycle accurate emulation. Modern CPUs contain superscalar out of
3602 order cores with complex cache hierarchies. The number of instructions
3603 executed often has little or no correlation with actual performance.
3605 @option{align=on} will activate the delay algorithm which will try
3606 to synchronise the host clock and the virtual clock. The goal is to
3607 have a guest running at the real frequency imposed by the shift option.
3608 Whenever the guest clock is behind the host clock and if
3609 @option{align=on} is specified then we print a message to the user
3610 to inform about the delay.
3611 Currently this option does not work when @option{shift} is @code{auto}.
3612 Note: The sync algorithm will work for those shift values for which
3613 the guest clock runs ahead of the host clock. Typically this happens
3614 when the shift value is high (how high depends on the host machine).
3616 When @option{rr} option is specified deterministic record/replay is enabled.
3617 Replay log is written into @var{filename} file in record mode and
3618 read from this file in replay mode.
3620 Option rrsnapshot is used to create new vm snapshot named @var{snapshot}
3621 at the start of execution recording. In replay mode this option is used
3622 to load the initial VM state.
3625 DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
3626 "-watchdog model\n" \
3627 " enable virtual hardware watchdog [default=none]\n",
3630 @item -watchdog @var{model}
3632 Create a virtual hardware watchdog device. Once enabled (by a guest
3633 action), the watchdog must be periodically polled by an agent inside
3634 the guest or else the guest will be restarted. Choose a model for
3635 which your guest has drivers.
3637 The @var{model} is the model of hardware watchdog to emulate. Use
3638 @code{-watchdog help} to list available hardware models. Only one
3639 watchdog can be enabled for a guest.
3641 The following models may be available:
3644 iBASE 700 is a very simple ISA watchdog with a single timer.
3646 Intel 6300ESB I/O controller hub is a much more featureful PCI-based
3647 dual-timer watchdog.
3649 A virtual watchdog for s390x backed by the diagnose 288 hypercall
3650 (currently KVM only).
3654 DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
3655 "-watchdog-action reset|shutdown|poweroff|inject-nmi|pause|debug|none\n" \
3656 " action when watchdog fires [default=reset]\n",
3659 @item -watchdog-action @var{action}
3660 @findex -watchdog-action
3662 The @var{action} controls what QEMU will do when the watchdog timer
3665 @code{reset} (forcefully reset the guest).
3666 Other possible actions are:
3667 @code{shutdown} (attempt to gracefully shutdown the guest),
3668 @code{poweroff} (forcefully poweroff the guest),
3669 @code{inject-nmi} (inject a NMI into the guest),
3670 @code{pause} (pause the guest),
3671 @code{debug} (print a debug message and continue), or
3672 @code{none} (do nothing).
3674 Note that the @code{shutdown} action requires that the guest responds
3675 to ACPI signals, which it may not be able to do in the sort of
3676 situations where the watchdog would have expired, and thus
3677 @code{-watchdog-action shutdown} is not recommended for production use.
3682 @item -watchdog i6300esb -watchdog-action pause
3683 @itemx -watchdog ib700
3687 DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
3688 "-echr chr set terminal escape character instead of ctrl-a\n",
3692 @item -echr @var{numeric_ascii_value}
3694 Change the escape character used for switching to the monitor when using
3695 monitor and serial sharing. The default is @code{0x01} when using the
3696 @code{-nographic} option. @code{0x01} is equal to pressing
3697 @code{Control-a}. You can select a different character from the ascii
3698 control keys where 1 through 26 map to Control-a through Control-z. For
3699 instance you could use the either of the following to change the escape
3700 character to Control-t.
3707 DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
3708 "-virtioconsole c\n" \
3709 " set virtio console\n", QEMU_ARCH_ALL)
3711 @item -virtioconsole @var{c}
3712 @findex -virtioconsole
3714 This option is deprecated, please use @option{-device virtconsole} instead.
3717 DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
3718 "-show-cursor show cursor\n", QEMU_ARCH_ALL)
3721 @findex -show-cursor
3725 DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
3726 "-tb-size n set TB size\n", QEMU_ARCH_ALL)
3728 @item -tb-size @var{n}
3733 DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
3734 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \
3735 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \
3736 "-incoming unix:socketpath\n" \
3737 " prepare for incoming migration, listen on\n" \
3738 " specified protocol and socket address\n" \
3739 "-incoming fd:fd\n" \
3740 "-incoming exec:cmdline\n" \
3741 " accept incoming migration on given file descriptor\n" \
3742 " or from given external command\n" \
3743 "-incoming defer\n" \
3744 " wait for the URI to be specified via migrate_incoming\n",
3747 @item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6]
3748 @itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6]
3750 Prepare for incoming migration, listen on a given tcp port.
3752 @item -incoming unix:@var{socketpath}
3753 Prepare for incoming migration, listen on a given unix socket.
3755 @item -incoming fd:@var{fd}
3756 Accept incoming migration from a given filedescriptor.
3758 @item -incoming exec:@var{cmdline}
3759 Accept incoming migration as an output from specified external command.
3761 @item -incoming defer
3762 Wait for the URI to be specified via migrate_incoming. The monitor can
3763 be used to change settings (such as migration parameters) prior to issuing
3764 the migrate_incoming to allow the migration to begin.
3767 DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \
3768 "-only-migratable allow only migratable devices\n", QEMU_ARCH_ALL)
3770 @item -only-migratable
3771 @findex -only-migratable
3772 Only allow migratable devices. Devices will not be allowed to enter an
3776 DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
3777 "-nodefaults don't create
default devices
\n", QEMU_ARCH_ALL)
3781 Don't create default devices. Normally, QEMU sets the default devices like serial
3782 port, parallel port, virtual console, monitor device, VGA adapter, floppy and
3783 CD-ROM drive and others. The @code{-nodefaults} option will disable all those
3788 DEF("chroot
", HAS_ARG, QEMU_OPTION_chroot, \
3789 "-chroot dir chroot to dir just before starting the VM
\n",
3793 @item -chroot @var{dir}
3795 Immediately before starting guest execution, chroot to the specified
3796 directory. Especially useful in combination with -runas.
3800 DEF("runas
", HAS_ARG, QEMU_OPTION_runas, \
3801 "-runas user change to user id user just before starting the VM
\n" \
3802 " user can be numeric uid
:gid instead
\n",
3806 @item -runas @var{user}
3808 Immediately before starting guest execution, drop root privileges, switching
3809 to the specified user.
3812 DEF("prom
-env
", HAS_ARG, QEMU_OPTION_prom_env,
3813 "-prom
-env variable
=value
\n"
3814 " set OpenBIOS nvram variables
\n",
3815 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3817 @item -prom-env @var{variable}=@var{value}
3819 Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
3821 DEF("semihosting
", 0, QEMU_OPTION_semihosting,
3822 "-semihosting semihosting mode
\n",
3823 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3827 @findex -semihosting
3828 Enable semihosting mode (ARM, M68K, Xtensa, MIPS only).
3830 DEF("semihosting
-config
", HAS_ARG, QEMU_OPTION_semihosting_config,
3831 "-semihosting
-config
[enable
=on|off
][,target
=native|gdb|auto
][,arg
=str
[,...]]\n" \
3832 " semihosting configuration
\n",
3833 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3836 @item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]
3837 @findex -semihosting-config
3838 Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only).
3840 @item target=@code{native|gdb|auto}
3841 Defines where the semihosting calls will be addressed, to QEMU (@code{native})
3842 or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb}
3843 during debug sessions and @code{native} otherwise.
3844 @item arg=@var{str1},arg=@var{str2},...
3845 Allows the user to pass input arguments, and can be used multiple times to build
3846 up a list. The old-style @code{-kernel}/@code{-append} method of passing a
3847 command line is still supported for backward compatibility. If both the
3848 @code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are
3849 specified, the former is passed to semihosting as it always takes precedence.
3852 DEF("old
-param
", 0, QEMU_OPTION_old_param,
3853 "-old
-param old param mode
\n", QEMU_ARCH_ARM)
3856 @findex -old-param (ARM)
3857 Old param mode (ARM only).
3860 DEF("sandbox
", HAS_ARG, QEMU_OPTION_sandbox, \
3861 "-sandbox on
[,obsolete
=allow|deny
][,elevateprivileges
=allow|deny|children
]\n" \
3862 " [,spawn
=allow|deny
][,resourcecontrol
=allow|deny
]\n" \
3863 " Enable seccomp mode
2 system call
filter (default 'off').\n" \
3864 " use
'obsolete' to allow obsolete system calls that are provided
\n" \
3865 " by the kernel
, but typically no longer used by modern
\n" \
3866 " C library implementations
.\n" \
3867 " use
'elevateprivileges' to allow or deny QEMU process to elevate
\n" \
3868 " its privileges by blacklisting all set
*uid|gid system calls
.\n" \
3869 " The value
'children' will deny set
*uid|gid system calls
for\n" \
3870 " main QEMU process but will allow forks and execves to run unprivileged
\n" \
3871 " use
'spawn' to avoid QEMU to spawn
new threads or processes by
\n" \
3872 " blacklisting
*fork and execve
\n" \
3873 " use
'resourcecontrol' to disable process affinity and schedular priority
\n",
3876 @item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}]
3878 Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
3879 disable it. The default is 'off'.
3881 @item obsolete=@var{string}
3882 Enable Obsolete system calls
3883 @item elevateprivileges=@var{string}
3884 Disable set*uid|gid system calls
3885 @item spawn=@var{string}
3886 Disable *fork and execve
3887 @item resourcecontrol=@var{string}
3888 Disable process affinity and schedular priority
3892 DEF("readconfig
", HAS_ARG, QEMU_OPTION_readconfig,
3893 "-readconfig
<file
>\n", QEMU_ARCH_ALL)
3895 @item -readconfig @var{file}
3897 Read device configuration from @var{file}. This approach is useful when you want to spawn
3898 QEMU process with many command line options but you don't want to exceed the command line
3901 DEF("writeconfig
", HAS_ARG, QEMU_OPTION_writeconfig,
3902 "-writeconfig
<file
>\n"
3903 " read
/write config file
\n", QEMU_ARCH_ALL)
3905 @item -writeconfig @var{file}
3906 @findex -writeconfig
3907 Write device configuration to @var{file}. The @var{file} can be either filename to save
3908 command line and device configuration into file or dash @code{-}) character to print the
3909 output to stdout. This can be later used as input file for @code{-readconfig} option.
3911 HXCOMM Deprecated, same as -no-user-config
3912 DEF("nodefconfig
", 0, QEMU_OPTION_nodefconfig, "", QEMU_ARCH_ALL)
3913 DEF("no
-user
-config
", 0, QEMU_OPTION_nouserconfig,
3915 " do not load
default user
-provided config files at startup
\n",
3918 @item -no-user-config
3919 @findex -no-user-config
3920 The @code{-no-user-config} option makes QEMU not load any of the user-provided
3921 config files on @var{sysconfdir}.
3923 DEF("trace", HAS_ARG, QEMU_OPTION_trace,
3924 "-trace [[enable
=]<pattern
>][,events
=<file
>][,file
=<file
>]\n"
3925 " specify tracing options
\n",
3928 HXCOMM This line is not accurate, as some sub-options are backend-specific but
3929 HXCOMM HX does not support conditional compilation of text.
3930 @item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}]
3932 @include qemu-option-trace.texi
3936 DEF("qtest
", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL)
3937 DEF("qtest
-log
", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL)
3940 DEF("enable
-fips
", 0, QEMU_OPTION_enablefips,
3941 "-enable
-fips enable FIPS
140-2 compliance
\n",
3946 @findex -enable-fips
3947 Enable FIPS 140-2 compliance mode.
3950 HXCOMM Deprecated by -machine accel=tcg property
3951 DEF("no
-kvm
", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386)
3953 DEF("msg
", HAS_ARG, QEMU_OPTION_msg,
3954 "-msg timestamp
[=on|off
]\n"
3955 " change the format of messages
\n"
3956 " on|off controls leading
timestamps (default:on
)\n",
3959 @item -msg timestamp[=on|off]
3961 prepend a timestamp to each log message.(default:on)
3964 DEF("dump
-vmstate
", HAS_ARG, QEMU_OPTION_dump_vmstate,
3965 "-dump
-vmstate
<file
>\n"
3966 " Output vmstate information
in JSON format to file
.\n"
3967 " Use the scripts
/vmstate
-static-checker
.py file to
\n"
3968 " check
for possible regressions
in migration code
\n"
3969 " by comparing two such vmstate dumps
.\n",
3972 @item -dump-vmstate @var{file}
3973 @findex -dump-vmstate
3974 Dump json-encoded vmstate information for current machine type to file
3983 DEFHEADING(Generic object creation:)
3988 DEF("object
", HAS_ARG, QEMU_OPTION_object,
3989 "-object TYPENAME
[,PROP1
=VALUE1
,...]\n"
3990 " create a
new object of type TYPENAME setting properties
\n"
3991 " in the order they are specified
. Note that the
'id'\n"
3992 " property must be set
. These objects are placed
in the
\n"
3993 " '/objects' path
.\n",
3996 @item -object @var{typename}[,@var{prop1}=@var{value1},...]
3998 Create a new object of type @var{typename} setting properties
3999 in the order they are specified. Note that the 'id'
4000 property must be set. These objects are placed in the
4005 @item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off},discard-data=@var{on|off},merge=@var{on|off},dump=@var{on|off},prealloc=@var{on|off},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave},align=@var{align}
4007 Creates a memory file backend object, which can be used to back
4008 the guest RAM with huge pages.
4010 The @option{id} parameter is a unique ID that will be used to reference this
4011 memory region when configuring the @option{-numa} argument.
4013 The @option{size} option provides the size of the memory region, and accepts
4014 common suffixes, eg @option{500M}.
4016 The @option{mem-path} provides the path to either a shared memory or huge page
4019 The @option{share} boolean option determines whether the memory
4020 region is marked as private to QEMU, or shared. The latter allows
4021 a co-operating external process to access the QEMU memory region.
4023 The @option{share} is also required for pvrdma devices due to
4024 limitations in the RDMA API provided by Linux.
4026 Setting share=on might affect the ability to configure NUMA
4027 bindings for the memory backend under some circumstances, see
4028 Documentation/vm/numa_memory_policy.txt on the Linux kernel
4029 source tree for additional details.
4031 Setting the @option{discard-data} boolean option to @var{on}
4032 indicates that file contents can be destroyed when QEMU exits,
4033 to avoid unnecessarily flushing data to the backing file. Note
4034 that @option{discard-data} is only an optimization, and QEMU
4035 might not discard file contents if it aborts unexpectedly or is
4036 terminated using SIGKILL.
4038 The @option{merge} boolean option enables memory merge, also known as
4039 MADV_MERGEABLE, so that Kernel Samepage Merging will consider the pages for
4040 memory deduplication.
4042 Setting the @option{dump} boolean option to @var{off} excludes the memory from
4043 core dumps. This feature is also known as MADV_DONTDUMP.
4045 The @option{prealloc} boolean option enables memory preallocation.
4047 The @option{host-nodes} option binds the memory range to a list of NUMA host
4050 The @option{policy} option sets the NUMA policy to one of the following values:
4056 @item @var{preferred}
4057 prefer the given host node list for allocation
4060 restrict memory allocation to the given host node list
4062 @item @var{interleave}
4063 interleave memory allocations across the given host node list
4066 The @option{align} option specifies the base address alignment when
4067 QEMU mmap(2) @option{mem-path}, and accepts common suffixes, eg
4068 @option{2M}. Some backend store specified by @option{mem-path}
4069 requires an alignment different than the default one used by QEMU, eg
4070 the device DAX /dev/dax0.0 requires 2M alignment rather than 4K. In
4071 such cases, users can specify the required alignment via this option.
4073 @item -object memory-backend-ram,id=@var{id},merge=@var{on|off},dump=@var{on|off},share=@var{on|off},prealloc=@var{on|off},size=@var{size},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave}
4075 Creates a memory backend object, which can be used to back the guest RAM.
4076 Memory backend objects offer more control than the @option{-m} option that is
4077 traditionally used to define guest RAM. Please refer to
4078 @option{memory-backend-file} for a description of the options.
4080 @item -object memory-backend-memfd,id=@var{id},merge=@var{on|off},dump=@var{on|off},prealloc=@var{on|off},size=@var{size},host-nodes=@var{host-nodes},policy=@var{default|preferred|bind|interleave},seal=@var{on|off},hugetlb=@var{on|off},hugetlbsize=@var{size}
4082 Creates an anonymous memory file backend object, which allows QEMU to
4083 share the memory with an external process (e.g. when using
4084 vhost-user). The memory is allocated with memfd and optional
4085 sealing. (Linux only)
4087 The @option{seal} option creates a sealed-file, that will block
4088 further resizing the memory ('on' by default).
4090 The @option{hugetlb} option specify the file to be created resides in
4091 the hugetlbfs filesystem (since Linux 4.14). Used in conjunction with
4092 the @option{hugetlb} option, the @option{hugetlbsize} option specify
4093 the hugetlb page size on systems that support multiple hugetlb page
4094 sizes (it must be a power of 2 value supported by the system).
4096 In some versions of Linux, the @option{hugetlb} option is incompatible
4097 with the @option{seal} option (requires at least Linux 4.16).
4099 Please refer to @option{memory-backend-file} for a description of the
4102 @item -object rng-random,id=@var{id},filename=@var{/dev/random}
4104 Creates a random number generator backend which obtains entropy from
4105 a device on the host. The @option{id} parameter is a unique ID that
4106 will be used to reference this entropy backend from the @option{virtio-rng}
4107 device. The @option{filename} parameter specifies which file to obtain
4108 entropy from and if omitted defaults to @option{/dev/random}.
4110 @item -object rng-egd,id=@var{id},chardev=@var{chardevid}
4112 Creates a random number generator backend which obtains entropy from
4113 an external daemon running on the host. The @option{id} parameter is
4114 a unique ID that will be used to reference this entropy backend from
4115 the @option{virtio-rng} device. The @option{chardev} parameter is
4116 the unique ID of a character device backend that provides the connection
4119 @item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off}
4121 Creates a TLS anonymous credentials object, which can be used to provide
4122 TLS support on network backends. The @option{id} parameter is a unique
4123 ID which network backends will use to access the credentials. The
4124 @option{endpoint} is either @option{server} or @option{client} depending
4125 on whether the QEMU network backend that uses the credentials will be
4126 acting as a client or as a server. If @option{verify-peer} is enabled
4127 (the default) then once the handshake is completed, the peer credentials
4128 will be verified, though this is a no-op for anonymous credentials.
4130 The @var{dir} parameter tells QEMU where to find the credential
4131 files. For server endpoints, this directory may contain a file
4132 @var{dh-params.pem} providing diffie-hellman parameters to use
4133 for the TLS server. If the file is missing, QEMU will generate
4134 a set of DH parameters at startup. This is a computationally
4135 expensive operation that consumes random pool entropy, so it is
4136 recommended that a persistent set of parameters be generated
4139 @item -object tls-creds-psk,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/keys/dir}[,username=@var{username}]
4141 Creates a TLS Pre-Shared Keys (PSK) credentials object, which can be used to provide
4142 TLS support on network backends. The @option{id} parameter is a unique
4143 ID which network backends will use to access the credentials. The
4144 @option{endpoint} is either @option{server} or @option{client} depending
4145 on whether the QEMU network backend that uses the credentials will be
4146 acting as a client or as a server. For clients only, @option{username}
4147 is the username which will be sent to the server. If omitted
4148 it defaults to ``qemu''.
4150 The @var{dir} parameter tells QEMU where to find the keys file.
4151 It is called ``@var{dir}/keys.psk'' and contains ``username:key''
4152 pairs. This file can most easily be created using the GnuTLS
4153 @code{psktool} program.
4155 For server endpoints, @var{dir} may also contain a file
4156 @var{dh-params.pem} providing diffie-hellman parameters to use
4157 for the TLS server. If the file is missing, QEMU will generate
4158 a set of DH parameters at startup. This is a computationally
4159 expensive operation that consumes random pool entropy, so it is
4160 recommended that a persistent set of parameters be generated
4163 @item -object tls-creds-x509,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},priority=@var{priority},verify-peer=@var{on|off},passwordid=@var{id}
4165 Creates a TLS anonymous credentials object, which can be used to provide
4166 TLS support on network backends. The @option{id} parameter is a unique
4167 ID which network backends will use to access the credentials. The
4168 @option{endpoint} is either @option{server} or @option{client} depending
4169 on whether the QEMU network backend that uses the credentials will be
4170 acting as a client or as a server. If @option{verify-peer} is enabled
4171 (the default) then once the handshake is completed, the peer credentials
4172 will be verified. With x509 certificates, this implies that the clients
4173 must be provided with valid client certificates too.
4175 The @var{dir} parameter tells QEMU where to find the credential
4176 files. For server endpoints, this directory may contain a file
4177 @var{dh-params.pem} providing diffie-hellman parameters to use
4178 for the TLS server. If the file is missing, QEMU will generate
4179 a set of DH parameters at startup. This is a computationally
4180 expensive operation that consumes random pool entropy, so it is
4181 recommended that a persistent set of parameters be generated
4184 For x509 certificate credentials the directory will contain further files
4185 providing the x509 certificates. The certificates must be stored
4186 in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional),
4187 @var{server-cert.pem} (only servers), @var{server-key.pem} (only servers),
4188 @var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients).
4190 For the @var{server-key.pem} and @var{client-key.pem} files which
4191 contain sensitive private keys, it is possible to use an encrypted
4192 version by providing the @var{passwordid} parameter. This provides
4193 the ID of a previously created @code{secret} object containing the
4194 password for decryption.
4196 The @var{priority} parameter allows to override the global default
4197 priority used by gnutls. This can be useful if the system administrator
4198 needs to use a weaker set of crypto priorities for QEMU without
4199 potentially forcing the weakness onto all applications. Or conversely
4200 if one wants wants a stronger default for QEMU than for all other
4201 applications, they can do this through this parameter. Its format is
4202 a gnutls priority string as described at
4203 @url{https://gnutls.org/manual/html_node/Priority-Strings.html}.
4205 @item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}]
4207 Interval @var{t} can't be 0, this filter batches the packet delivery: all
4208 packets arriving in a given interval on netdev @var{netdevid} are delayed
4209 until the end of the interval. Interval is in microseconds.
4210 @option{status} is optional that indicate whether the netfilter is
4211 on (enabled) or off (disabled), the default status for netfilter will be 'on'.
4213 queue @var{all|rx|tx} is an option that can be applied to any netfilter.
4215 @option{all}: the filter is attached both to the receive and the transmit
4216 queue of the netdev (default).
4218 @option{rx}: the filter is attached to the receive queue of the netdev,
4219 where it will receive packets sent to the netdev.
4221 @option{tx}: the filter is attached to the transmit queue of the netdev,
4222 where it will receive packets sent by the netdev.
4224 @item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4226 filter-mirror on netdev @var{netdevid},mirror net packet to chardev@var{chardevid}, if it has the vnet_hdr_support flag, filter-mirror will mirror packet with vnet_hdr_len.
4228 @item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4230 filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev
4231 @var{chardevid},and redirect indev's packet to filter.if it has the vnet_hdr_support flag,
4232 filter-redirector will redirect packet with vnet_hdr_len.
4233 Create a filter-redirector we need to differ outdev id from indev id, id can not
4234 be the same. we can just use indev or outdev, but at least one of indev or outdev
4235 need to be specified.
4237 @item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support]
4239 Filter-rewriter is a part of COLO project.It will rewrite tcp packet to
4240 secondary from primary to keep secondary tcp connection,and rewrite
4241 tcp packet to primary from secondary make tcp packet can be handled by
4242 client.if it has the vnet_hdr_support flag, we can parse packet with vnet header.
4246 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4247 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4248 -object filter-rewriter,id=rew0,netdev=hn0,queue=all
4250 @item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}]
4252 Dump the network traffic on netdev @var{dev} to the file specified by
4253 @var{filename}. At most @var{len} bytes (64k by default) per packet are stored.
4254 The file format is libpcap, so it can be analyzed with tools such as tcpdump
4257 @item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid}[,vnet_hdr_support]
4259 Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with
4260 secondary packet. If the packets are same, we will output primary
4261 packet to outdev@var{chardevid}, else we will notify colo-frame
4262 do checkpoint and send primary packet to outdev@var{chardevid}.
4263 if it has the vnet_hdr_support flag, colo compare will send/recv packet with vnet_hdr_len.
4265 we must use it with the help of filter-mirror and filter-redirector.
4270 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown
4271 -device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66
4272 -chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait
4273 -chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait
4274 -chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait
4275 -chardev socket,id=compare0-0,host=3.3.3.3,port=9001
4276 -chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait
4277 -chardev socket,id=compare_out0,host=3.3.3.3,port=9005
4278 -object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0
4279 -object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out
4280 -object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0
4281 -object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0
4284 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown
4285 -device e1000,netdev=hn0,mac=52:a4:00:12:78:66
4286 -chardev socket,id=red0,host=3.3.3.3,port=9003
4287 -chardev socket,id=red1,host=3.3.3.3,port=9004
4288 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4289 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4293 If you want to know the detail of above command line, you can read
4294 the colo-compare git log.
4296 @item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}]
4298 Creates a cryptodev backend which executes crypto opreation from
4299 the QEMU cipher APIS. The @var{id} parameter is
4300 a unique ID that will be used to reference this cryptodev backend from
4301 the @option{virtio-crypto} device. The @var{queues} parameter is optional,
4302 which specify the queue number of cryptodev backend, the default of
4307 # qemu-system-x86_64 \
4309 -object cryptodev-backend-builtin,id=cryptodev0 \
4310 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4314 @item -object cryptodev-vhost-user,id=@var{id},chardev=@var{chardevid}[,queues=@var{queues}]
4316 Creates a vhost-user cryptodev backend, backed by a chardev @var{chardevid}.
4317 The @var{id} parameter is a unique ID that will be used to reference this
4318 cryptodev backend from the @option{virtio-crypto} device.
4319 The chardev should be a unix domain socket backed one. The vhost-user uses
4320 a specifically defined protocol to pass vhost ioctl replacement messages
4321 to an application on the other end of the socket.
4322 The @var{queues} parameter is optional, which specify the queue number
4323 of cryptodev backend for multiqueue vhost-user, the default of @var{queues} is 1.
4327 # qemu-system-x86_64 \
4329 -chardev socket,id=chardev0,path=/path/to/socket \
4330 -object cryptodev-vhost-user,id=cryptodev0,chardev=chardev0 \
4331 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4335 @item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4336 @item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4338 Defines a secret to store a password, encryption key, or some other sensitive
4339 data. The sensitive data can either be passed directly via the @var{data}
4340 parameter, or indirectly via the @var{file} parameter. Using the @var{data}
4341 parameter is insecure unless the sensitive data is encrypted.
4343 The sensitive data can be provided in raw format (the default), or base64.
4344 When encoded as JSON, the raw format only supports valid UTF-8 characters,
4345 so base64 is recommended for sending binary data. QEMU will convert from
4346 which ever format is provided to the format it needs internally. eg, an
4347 RBD password can be provided in raw format, even though it will be base64
4348 encoded when passed onto the RBD sever.
4350 For added protection, it is possible to encrypt the data associated with
4351 a secret using the AES-256-CBC cipher. Use of encryption is indicated
4352 by providing the @var{keyid} and @var{iv} parameters. The @var{keyid}
4353 parameter provides the ID of a previously defined secret that contains
4354 the AES-256 decryption key. This key should be 32-bytes long and be
4355 base64 encoded. The @var{iv} parameter provides the random initialization
4356 vector used for encryption of this particular secret and should be a
4357 base64 encrypted string of the 16-byte IV.
4359 The simplest (insecure) usage is to provide the secret inline
4363 # $QEMU -object secret,id=sec0,data=letmein,format=raw
4367 The simplest secure usage is to provide the secret via a file
4369 # printf "letmein
" > mypasswd.txt
4370 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw
4372 For greater security, AES-256-CBC should be used. To illustrate usage,
4373 consider the openssl command line tool which can encrypt the data. Note
4374 that when encrypting, the plaintext must be padded to the cipher block
4375 size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm.
4377 First a master key needs to be created in base64 encoding:
4380 # openssl rand -base64 32 > key.b64
4381 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X
"')
4384 Each secret to be encrypted needs to have a random initialization vector
4385 generated. These do not need to be kept secret
4388 # openssl rand -base64 16 > iv.b64
4389 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X
"')
4392 The secret to be defined can now be encrypted, in this case we're
4393 telling openssl to base64 encode the result, but it could be left
4394 as raw bytes if desired.
4397 # SECRET=$(printf "letmein
" |
4398 openssl enc -aes-256-cbc -a -K $KEY -iv $IV)
4401 When launching QEMU, create a master secret pointing to @code{key.b64}
4402 and specify that to be used to decrypt the user password. Pass the
4403 contents of @code{iv.b64} to the second secret
4407 -object secret,id=secmaster0,format=base64,file=key.b64 \
4408 -object secret,id=sec0,keyid=secmaster0,format=base64,\
4409 data=$SECRET,iv=$(<iv.b64)
4412 @item -object sev-guest,id=@var{id},cbitpos=@var{cbitpos},reduced-phys-bits=@var{val},[sev-device=@var{string},policy=@var{policy},handle=@var{handle},dh-cert-file=@var{file},session-file=@var{file}]
4414 Create a Secure Encrypted Virtualization (SEV) guest object, which can be used
4415 to provide the guest memory encryption support on AMD processors.
4417 When memory encryption is enabled, one of the physical address bit (aka the
4418 C-bit) is utilized to mark if a memory page is protected. The @option{cbitpos}
4419 is used to provide the C-bit position. The C-bit position is Host family dependent
4420 hence user must provide this value. On EPYC, the value should be 47.
4422 When memory encryption is enabled, we loose certain bits in physical address space.
4423 The @option{reduced-phys-bits} is used to provide the number of bits we loose in
4424 physical address space. Similar to C-bit, the value is Host family dependent.
4425 On EPYC, the value should be 5.
4427 The @option{sev-device} provides the device file to use for communicating with
4428 the SEV firmware running inside AMD Secure Processor. The default device is
4429 '/dev/sev'. If hardware supports memory encryption then /dev/sev devices are
4430 created by CCP driver.
4432 The @option{policy} provides the guest policy to be enforced by the SEV firmware
4433 and restrict what configuration and operational commands can be performed on this
4434 guest by the hypervisor. The policy should be provided by the guest owner and is
4435 bound to the guest and cannot be changed throughout the lifetime of the guest.
4438 If guest @option{policy} allows sharing the key with another SEV guest then
4439 @option{handle} can be use to provide handle of the guest from which to share
4442 The @option{dh-cert-file} and @option{session-file} provides the guest owner's
4443 Public Diffie-Hillman key defined in SEV spec. The PDH and session parameters
4444 are used for establishing a cryptographic session with the guest owner to
4445 negotiate keys used for attestation. The file must be encoded in base64.
4447 e.g to launch a SEV guest
4451 -object sev-guest,id=sev0,cbitpos=47,reduced-phys-bits=5 \
4452 -machine ...,memory-encryption=sev0
4461 HXCOMM This is the last statement. Insert new options before this line!