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",
49 @item
-machine
[type
=]@
var{name
}[,prop
=@
var{value
}[,...]]
51 Select the emulated machine by @
var{name
}. Use @code
{-machine help
} to list
54 For architectures which aim to support live migration compatibility
55 across releases
, each release will introduce a
new versioned machine
56 type
. For example
, the
2.8.0 release introduced machine types
57 ``pc
-i440fx
-2.8'' and ``pc
-q35
-2.8'' for the x86_64
/i686 architectures
.
59 To allow live migration of guests from QEMU version
2.8.0, to QEMU
60 version
2.9.0, the
2.9.0 version must support the ``pc
-i440fx
-2.8''
61 and ``pc
-q35
-2.8'' machines too
. To allow users live migrating VMs
62 to skip multiple intermediate releases when upgrading
, new releases
63 of QEMU will support machine types from many previous versions
.
65 Supported machine properties are
:
67 @item accel
=@
var{accels1
}[:@
var{accels2
}[:...]]
68 This is used to enable an accelerator
. Depending on the target architecture
,
69 kvm
, xen
, hax
, hvf
, whpx or tcg can be available
. By
default, tcg is used
. If there is
70 more than one accelerator specified
, the next one is used
if the previous one
72 @item kernel_irqchip
=on|off
73 Controls
in-kernel irqchip support
for the chosen accelerator when available
.
74 @item gfx_passthru
=on|off
75 Enables IGD GFX passthrough support
for the chosen machine when available
.
76 @item vmport
=on|off|auto
77 Enables emulation of VMWare IO port
, for vmmouse etc
. auto says to select the
78 value based on accel
. For accel
=xen the
default is off otherwise the
default
80 @item kvm_shadow_mem
=size
81 Defines the size of the KVM shadow MMU
.
82 @item dump
-guest
-core
=on|off
83 Include guest memory
in a core dump
. The
default is on
.
84 @item mem
-merge
=on|off
85 Enables or disables memory merge support
. This feature
, when supported by
86 the host
, de
-duplicates identical memory pages among VMs instances
88 @item aes
-key
-wrap
=on|off
89 Enables or disables AES key wrapping support on s390
-ccw hosts
. This feature
90 controls whether AES wrapping keys will be created to allow
91 execution of AES cryptographic functions
. The
default is on
.
92 @item dea
-key
-wrap
=on|off
93 Enables or disables DEA key wrapping support on s390
-ccw hosts
. This feature
94 controls whether DEA wrapping keys will be created to allow
95 execution of DEA cryptographic functions
. The
default is on
.
97 Enables or disables NVDIMM support
. The
default is off
.
98 @item s390
-squash
-mcss
=on|off
99 Enables or disables squashing subchannels into the
default css
.
101 NOTE
: This property is deprecated and will be removed
in future releases
.
102 The ``s390
-squash
-mcss
=on`` property has been obsoleted by allowing the
103 cssid to be chosen freely
. Instead of squashing subchannels into the
104 default channel subsystem image
for guests that
do not support multiple
105 channel subsystems
, all devices can be put into the
default channel
107 @item enforce
-config
-section
=on|off
108 If @option
{enforce
-config
-section
} is set to @
var{on
}, force migration
109 code to send configuration section even
if the machine
-type sets the
110 @option
{migration
.send
-configuration
} property to @
var{off
}.
111 NOTE
: this parameter is deprecated
. Please use @option
{-global
}
112 @option
{migration
.send
-configuration
}=@
var{on|off
} instead
.
116 HXCOMM Deprecated by
-machine
117 DEF("M", HAS_ARG
, QEMU_OPTION_M
, "", QEMU_ARCH_ALL
)
119 DEF("cpu", HAS_ARG
, QEMU_OPTION_cpu
,
120 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL
)
122 @item
-cpu @
var{model
}
124 Select CPU
model (@code
{-cpu help
} for list and additional feature selection
)
127 DEF("accel", HAS_ARG
, QEMU_OPTION_accel
,
128 "-accel [accel=]accelerator[,thread=single|multi]\n"
129 " select accelerator (kvm, xen, hax, hvf, whpx or tcg; use 'help' for a list)\n"
130 " thread=single|multi (enable multi-threaded TCG)", QEMU_ARCH_ALL
)
132 @item
-accel @
var{name
}[,prop
=@
var{value
}[,...]]
134 This is used to enable an accelerator
. Depending on the target architecture
,
135 kvm
, xen
, hax
, hvf
, whpx or tcg can be available
. By
default, tcg is used
. If there is
136 more than one accelerator specified
, the next one is used
if the previous one
139 @item thread
=single|multi
140 Controls number of TCG threads
. When the TCG is multi
-threaded there will be one
141 thread per vCPU therefor taking advantage of additional host cores
. The
default
142 is to enable multi
-threading where both the back
-end and front
-ends support it and
143 no incompatible TCG features have been
enabled (e
.g
. icount
/replay
).
147 DEF("smp", HAS_ARG
, QEMU_OPTION_smp
,
148 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
149 " set the number of CPUs to 'n' [default=1]\n"
150 " maxcpus= maximum number of total cpus, including\n"
151 " offline CPUs for hotplug, etc\n"
152 " cores= number of CPU cores on one socket\n"
153 " threads= number of threads on one CPU core\n"
154 " sockets= number of discrete sockets in the system\n",
157 @item
-smp
[cpus
=]@
var{n
}[,cores
=@
var{cores
}][,threads
=@
var{threads
}][,sockets
=@
var{sockets
}][,maxcpus
=@
var{maxcpus
}]
159 Simulate an SMP system with @
var{n
} CPUs
. On the PC target
, up to
255
160 CPUs are supported
. On Sparc32 target
, Linux limits the number of usable CPUs
162 For the PC target
, the number of @
var{cores
} per socket
, the number
163 of @
var{threads
} per cores and the total number of @
var{sockets
} can be
164 specified
. Missing values will be computed
. If any on the three values is
165 given
, the total number of CPUs @
var{n
} can be omitted
. @
var{maxcpus
}
166 specifies the maximum number of hotpluggable CPUs
.
169 DEF("numa", HAS_ARG
, QEMU_OPTION_numa
,
170 "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
171 "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
172 "-numa dist,src=source,dst=destination,val=distance\n"
173 "-numa cpu,node-id=node[,socket-id=x][,core-id=y][,thread-id=z]\n",
176 @item
-numa node
[,mem
=@
var{size
}][,cpus
=@
var{firstcpu
}[-@
var{lastcpu
}]][,nodeid
=@
var{node
}]
177 @itemx
-numa node
[,memdev
=@
var{id
}][,cpus
=@
var{firstcpu
}[-@
var{lastcpu
}]][,nodeid
=@
var{node
}]
178 @itemx
-numa dist
,src
=@
var{source
},dst
=@
var{destination
},val
=@
var{distance
}
179 @itemx
-numa cpu
,node
-id
=@
var{node
}[,socket
-id
=@
var{x
}][,core
-id
=@
var{y
}][,thread
-id
=@
var{z
}]
181 Define a NUMA node and assign RAM and VCPUs to it
.
182 Set the NUMA distance from a source node to a destination node
.
184 Legacy VCPU assignment uses @samp
{cpus
} option where
185 @
var{firstcpu
} and @
var{lastcpu
} are CPU indexes
. Each
186 @samp
{cpus
} option represent a contiguous range of CPU indexes
187 (or a single VCPU
if @
var{lastcpu
} is omitted
). A non
-contiguous
188 set of VCPUs can be represented by providing multiple @samp
{cpus
}
189 options
. If @samp
{cpus
} is omitted on all nodes
, VCPUs are automatically
192 For example
, the following option assigns VCPUs
0, 1, 2 and
5 to
195 -numa node
,cpus
=0-2,cpus
=5
198 @samp
{cpu
} option is a
new alternative to @samp
{cpus
} option
199 which uses @samp
{socket
-id|core
-id|thread
-id
} properties to assign
200 CPU objects to a @
var{node
} using topology layout properties of CPU
.
201 The set of properties is machine specific
, and depends on used
202 machine type
/@samp
{smp
} options
. It could be queried with
203 @samp
{hotpluggable
-cpus
} monitor command
.
204 @samp
{node
-id
} property specifies @
var{node
} to which CPU object
205 will be assigned
, it
's required for @var{node} to be declared
206 with @samp{node} option before it's used with @samp
{cpu
} option
.
211 -smp
1,sockets
=2,maxcpus
=2 \
212 -numa node
,nodeid
=0 -numa node
,nodeid
=1 \
213 -numa cpu
,node
-id
=0,socket
-id
=0 -numa cpu
,node
-id
=1,socket
-id
=1
216 @samp
{mem
} assigns a given RAM amount to a node
. @samp
{memdev
}
217 assigns RAM from a given memory backend device to a node
. If
218 @samp
{mem
} and @samp
{memdev
} are omitted
in all nodes
, RAM is
219 split equally between them
.
221 @samp
{mem
} and @samp
{memdev
} are mutually exclusive
. Furthermore
,
222 if one node uses @samp
{memdev
}, all of them have to use it
.
224 @
var{source
} and @
var{destination
} are NUMA node IDs
.
225 @
var{distance
} is the NUMA distance from @
var{source
} to @
var{destination
}.
226 The distance from a node to itself is always
10. If any pair of nodes is
227 given a distance
, then all pairs must be given distances
. Although
, when
228 distances are only given
in one direction
for each pair of nodes
, then
229 the distances
in the opposite directions are assumed to be the same
. If
,
230 however
, an asymmetrical pair of distances is given
for even one node
231 pair
, then all node pairs must be provided distance values
for both
232 directions
, even when they are symmetrical
. When a node is unreachable
233 from another node
, set the pair
's distance to 255.
235 Note that the -@option{numa} option doesn't allocate any of the
236 specified resources
, it just assigns existing resources to NUMA
237 nodes
. This means that one still has to use the @option
{-m
},
238 @option
{-smp
} options to allocate RAM and VCPUs respectively
.
242 DEF("add-fd", HAS_ARG
, QEMU_OPTION_add_fd
,
243 "-add-fd fd=fd,set=set[,opaque=opaque]\n"
244 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL
)
246 @item
-add
-fd fd
=@
var{fd
},set
=@
var{set
}[,opaque
=@
var{opaque
}]
249 Add a file descriptor to an fd set
. Valid options are
:
253 This option defines the file descriptor of which a duplicate is added to fd set
.
254 The file descriptor cannot be stdin
, stdout
, or stderr
.
256 This option defines the ID of the fd set to add the file descriptor to
.
257 @item opaque
=@
var{opaque
}
258 This option defines a free
-form string that can be used to describe @
var{fd
}.
261 You can open an image
using pre
-opened file descriptors from an fd set
:
264 -add
-fd fd
=3,set
=2,opaque
="rdwr:/path/to/file"
265 -add
-fd fd
=4,set
=2,opaque
="rdonly:/path/to/file"
266 -drive file
=/dev
/fdset
/2,index
=0,media
=disk
270 DEF("set", HAS_ARG
, QEMU_OPTION_set
,
271 "-set group.id.arg=value\n"
272 " set <arg> parameter for item <id> of type <group>\n"
273 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL
)
275 @item
-set @
var{group
}.@
var{id
}.@
var{arg
}=@
var{value
}
277 Set parameter @
var{arg
} for item @
var{id
} of type @
var{group
}
280 DEF("global", HAS_ARG
, QEMU_OPTION_global
,
281 "-global driver.property=value\n"
282 "-global driver=driver,property=property,value=value\n"
283 " set a global default for a driver property\n",
286 @item
-global @
var{driver
}.@
var{prop
}=@
var{value
}
287 @itemx
-global driver
=@
var{driver
},property
=@
var{property
},value
=@
var{value
}
289 Set
default value of @
var{driver
}'s property @var{prop} to @var{value}, e.g.:
292 qemu-system-i386 -global ide-hd.physical_block_size=4096 disk-image.img
295 In particular, you can use this to set driver properties for devices which are
296 created automatically by the machine model. To create a device which is not
297 created automatically and set properties on it, use -@option{device}.
299 -global @var{driver}.@var{prop}=@var{value} is shorthand for -global
300 driver=@var{driver},property=@var{prop},value=@var{value}. The
301 longhand syntax works even when @var{driver} contains a dot.
304 DEF("boot", HAS_ARG, QEMU_OPTION_boot,
305 "-boot [order=drives][,once=drives][,menu=on|off]\n"
306 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
307 " 'drives
': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
308 " 'sp_name
': the file's name that would be passed to bios as logo picture
, if menu
=on
\n"
309 " 'sp_time': the period that splash picture last
if menu
=on
, unit is ms
\n"
310 " 'rb_timeout': the timeout before guest reboot when boot failed
, unit is ms
\n",
313 @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]
315 Specify boot order @var{drives} as a string of drive letters. Valid
316 drive letters depend on the target architecture. The x86 PC uses: a, b
317 (floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
318 from network adapter 1-4), hard disk boot is the default. To apply a
319 particular boot order only on the first startup, specify it via
320 @option{once}. Note that the @option{order} or @option{once} parameter
321 should not be used together with the @option{bootindex} property of
322 devices, since the firmware implementations normally do not support both
325 Interactive boot menus/prompts can be enabled via @option{menu=on} as far
326 as firmware/BIOS supports them. The default is non-interactive boot.
328 A splash picture could be passed to bios, enabling user to show it as logo,
329 when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
330 supports them. Currently Seabios for X86 system support it.
331 limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
332 format(true color). The resolution should be supported by the SVGA mode, so
333 the recommended is 320x240, 640x480, 800x640.
335 A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms
336 when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not
337 reboot, qemu passes '-1' to bios by default. Currently Seabios for X86
340 Do strict boot via @option{strict=on} as far as firmware/BIOS
341 supports it. This only effects when boot priority is changed by
342 bootindex options. The default is non-strict boot.
345 # try to boot from network first, then from hard disk
346 qemu-system-i386 -boot order=nc
347 # boot from CD-ROM first, switch back to default order after reboot
348 qemu-system-i386 -boot once=d
349 # boot with a splash picture for 5 seconds.
350 qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
353 Note: The legacy format '-boot @var{drives}' is still supported but its
354 use is discouraged as it may be removed from future versions.
357 DEF("m
", HAS_ARG, QEMU_OPTION_m,
358 "-m
[size
=]megs
[,slots
=n
,maxmem
=size
]\n"
359 " configure guest RAM
\n"
360 " size
: initial amount of guest memory
\n"
361 " slots
: number of hotplug
slots (default: none
)\n"
362 " maxmem
: maximum amount of guest
memory (default: none
)\n"
363 "NOTE
: Some architectures might enforce a specific granularity
\n",
366 @item -m [size=]@var{megs}[,slots=n,maxmem=size]
368 Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB.
369 Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in
370 megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem}
371 could be used to set amount of hotpluggable memory slots and maximum amount of
372 memory. Note that @var{maxmem} must be aligned to the page size.
374 For example, the following command-line sets the guest startup RAM size to
375 1GB, creates 3 slots to hotplug additional memory and sets the maximum
376 memory the guest can reach to 4GB:
379 qemu-system-x86_64 -m 1G,slots=3,maxmem=4G
382 If @var{slots} and @var{maxmem} are not specified, memory hotplug won't
383 be enabled and the guest startup RAM will never increase.
386 DEF("mem
-path
", HAS_ARG, QEMU_OPTION_mempath,
387 "-mem
-path FILE provide backing storage
for guest RAM
\n", QEMU_ARCH_ALL)
389 @item -mem-path @var{path}
391 Allocate guest RAM from a temporarily created file in @var{path}.
394 DEF("mem
-prealloc
", 0, QEMU_OPTION_mem_prealloc,
395 "-mem
-prealloc preallocate guest
memory (use with
-mem
-path
)\n",
399 @findex -mem-prealloc
400 Preallocate memory when using -mem-path.
403 DEF("k
", HAS_ARG, QEMU_OPTION_k,
404 "-k language use keyboard
layout (for example
'fr' for French
)\n",
407 @item -k @var{language}
409 Use keyboard layout @var{language} (for example @code{fr} for
410 French). This option is only needed where it is not easy to get raw PC
411 keycodes (e.g. on Macs, with some X11 servers or with a VNC or curses
412 display). You don't normally need to use it on PC/Linux or PC/Windows
415 The available layouts are:
417 ar de-ch es fo fr-ca hu ja mk no pt-br sv
418 da en-gb et fr fr-ch is lt nl pl ru th
419 de en-us fi fr-be hr it lv nl-be pt sl tr
422 The default is @code{en-us}.
426 DEF("audio
-help
", 0, QEMU_OPTION_audio_help,
427 "-audio
-help print list of audio drivers and their options
\n",
432 Will show the audio subsystem help: list of drivers, tunable
436 DEF("soundhw
", HAS_ARG, QEMU_OPTION_soundhw,
437 "-soundhw c1
,... enable audio support
\n"
438 " and only specified sound
cards (comma separated list
)\n"
439 " use
'-soundhw help' to get the list of supported cards
\n"
440 " use
'-soundhw all' to enable all of them
\n", QEMU_ARCH_ALL)
442 @item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
444 Enable audio and selected sound hardware. Use 'help' to print all
445 available sound hardware.
448 qemu-system-i386 -soundhw sb16,adlib disk.img
449 qemu-system-i386 -soundhw es1370 disk.img
450 qemu-system-i386 -soundhw ac97 disk.img
451 qemu-system-i386 -soundhw hda disk.img
452 qemu-system-i386 -soundhw all disk.img
453 qemu-system-i386 -soundhw help
456 Note that Linux's i810_audio OSS kernel (for AC97) module might
457 require manually specifying clocking.
460 modprobe i810_audio clocking=48000
464 DEF("balloon
", HAS_ARG, QEMU_OPTION_balloon,
465 "-balloon virtio
[,addr
=str
]\n"
466 " enable virtio balloon
device (deprecated
)\n", QEMU_ARCH_ALL)
468 @item -balloon virtio[,addr=@var{addr}]
470 Enable virtio balloon device, optionally with PCI address @var{addr}. This
471 option is deprecated, use @option{--device virtio-balloon} instead.
474 DEF("device
", HAS_ARG, QEMU_OPTION_device,
475 "-device driver
[,prop
[=value
][,...]]\n"
476 " add
device (based on driver
)\n"
477 " prop
=value
,... sets driver properties
\n"
478 " use
'-device help' to print all possible drivers
\n"
479 " use
'-device driver,help' to print all possible properties
\n",
482 @item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
484 Add device @var{driver}. @var{prop}=@var{value} sets driver
485 properties. Valid properties depend on the driver. To get help on
486 possible drivers and properties, use @code{-device help} and
487 @code{-device @var{driver},help}.
490 @item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}][,sdrfile=@var{file}][,furareasize=@var{val}][,furdatafile=@var{file}]
492 Add an IPMI BMC. This is a simulation of a hardware management
493 interface processor that normally sits on a system. It provides
494 a watchdog and the ability to reset and power control the system.
495 You need to connect this to an IPMI interface to make it useful
497 The IPMI slave address to use for the BMC. The default is 0x20.
498 This address is the BMC's address on the I2C network of management
499 controllers. If you don't know what this means, it is safe to ignore
504 The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
505 @item slave_addr=@var{val}
506 Define slave address to use for the BMC. The default is 0x20.
507 @item sdrfile=@var{file}
508 file containing raw Sensor Data Records (SDR) data. The default is none.
509 @item fruareasize=@var{val}
510 size of a Field Replaceable Unit (FRU) area. The default is 1024.
511 @item frudatafile=@var{file}
512 file containing raw Field Replaceable Unit (FRU) inventory data. The default is none.
515 @item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}]
517 Add a connection to an external IPMI BMC simulator. Instead of
518 locally emulating the BMC like the above item, instead connect
519 to an external entity that provides the IPMI services.
521 A connection is made to an external BMC simulator. If you do this, it
522 is strongly recommended that you use the "reconnect
=" chardev option
523 to reconnect to the simulator if the connection is lost. Note that if
524 this is not used carefully, it can be a security issue, as the
525 interface has the ability to send resets, NMIs, and power off the VM.
526 It's best if QEMU makes a connection to an external simulator running
527 on a secure port on localhost, so neither the simulator nor QEMU is
528 exposed to any outside network.
530 See the "lanserv
/README
.vm
" file in the OpenIPMI library for more
531 details on the external interface.
533 @item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
535 Add a KCS IPMI interafce on the ISA bus. This also adds a
536 corresponding ACPI and SMBIOS entries, if appropriate.
540 The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
541 @item ioport=@var{val}
542 Define the I/O address of the interface. The default is 0xca0 for KCS.
544 Define the interrupt to use. The default is 5. To disable interrupts,
548 @item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
550 Like the KCS interface, but defines a BT interface. The default port is
551 0xe4 and the default interrupt is 5.
555 DEF("name
", HAS_ARG, QEMU_OPTION_name,
556 "-name string1
[,process
=string2
][,debug
-threads
=on|off
]\n"
557 " set the name of the guest
\n"
558 " string1 sets the window title and string2 the process
name (on Linux
)\n"
559 " When debug
-threads is enabled
, individual threads are given a separate
name (on Linux
)\n"
560 " NOTE
: The thread names are
for debugging and not a stable API
.\n",
563 @item -name @var{name}
565 Sets the @var{name} of the guest.
566 This name will be displayed in the SDL window caption.
567 The @var{name} will also be used for the VNC server.
568 Also optionally set the top visible process name in Linux.
569 Naming of individual threads can also be enabled on Linux to aid debugging.
572 DEF("uuid
", HAS_ARG, QEMU_OPTION_uuid,
573 "-uuid
%08x
-%04x
-%04x
-%04x
-%012x
\n"
574 " specify machine UUID
\n", QEMU_ARCH_ALL)
576 @item -uuid @var{uuid}
586 DEFHEADING(Block device options:)
591 DEF("fda
", HAS_ARG, QEMU_OPTION_fda,
592 "-fda
/-fdb file use
'file' as floppy disk
0/1 image
\n", QEMU_ARCH_ALL)
593 DEF("fdb
", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
595 @item -fda @var{file}
596 @itemx -fdb @var{file}
599 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}).
602 DEF("hda
", HAS_ARG, QEMU_OPTION_hda,
603 "-hda
/-hdb file use
'file' as IDE hard disk
0/1 image
\n", QEMU_ARCH_ALL)
604 DEF("hdb
", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
605 DEF("hdc
", HAS_ARG, QEMU_OPTION_hdc,
606 "-hdc
/-hdd file use
'file' as IDE hard disk
2/3 image
\n", QEMU_ARCH_ALL)
607 DEF("hdd
", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
609 @item -hda @var{file}
610 @itemx -hdb @var{file}
611 @itemx -hdc @var{file}
612 @itemx -hdd @var{file}
617 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
620 DEF("cdrom
", HAS_ARG, QEMU_OPTION_cdrom,
621 "-cdrom file use
'file' as IDE cdrom
image (cdrom is ide1 master
)\n",
624 @item -cdrom @var{file}
626 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
627 @option{-cdrom} at the same time). You can use the host CD-ROM by
628 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
631 DEF("blockdev
", HAS_ARG, QEMU_OPTION_blockdev,
632 "-blockdev
[driver
=]driver
[,node
-name
=N
][,discard
=ignore|unmap
]\n"
633 " [,cache
.direct
=on|off
][,cache
.no
-flush
=on|off
]\n"
634 " [,read
-only
=on|off
][,detect
-zeroes
=on|off|unmap
]\n"
635 " [,driver specific parameters
...]\n"
636 " configure a block backend
\n", QEMU_ARCH_ALL)
638 @item -blockdev @var{option}[,@var{option}[,@var{option}[,...]]]
641 Define a new block driver node. Some of the options apply to all block drivers,
642 other options are only accepted for a specific block driver. See below for a
643 list of generic options and options for the most common block drivers.
645 Options that expect a reference to another node (e.g. @code{file}) can be
646 given in two ways. Either you specify the node name of an already existing node
647 (file=@var{node-name}), or you define a new node inline, adding options
648 for the referenced node after a dot (file.filename=@var{path},file.aio=native).
650 A block driver node created with @option{-blockdev} can be used for a guest
651 device by specifying its node name for the @code{drive} property in a
652 @option{-device} argument that defines a block device.
655 @item Valid options for any block driver node:
659 Specifies the block driver to use for the given node.
661 This defines the name of the block driver node by which it will be referenced
662 later. The name must be unique, i.e. it must not match the name of a different
663 block driver node, or (if you use @option{-drive} as well) the ID of a drive.
665 If no node name is specified, it is automatically generated. The generated node
666 name is not intended to be predictable and changes between QEMU invocations.
667 For the top level, an explicit node name must be specified.
669 Open the node read-only. Guest write attempts will fail.
671 The host page cache can be avoided with @option{cache.direct=on}. This will
672 attempt to do disk IO directly to the guest's memory. QEMU may still perform an
673 internal copy of the data.
675 In case you don't care about data integrity over host failures, you can use
676 @option{cache.no-flush=on}. This option tells QEMU that it never needs to write
677 any data to the disk but can instead keep things in cache. If anything goes
678 wrong, like your host losing power, the disk storage getting disconnected
679 accidentally, etc. your image will most probably be rendered unusable.
680 @item discard=@var{discard}
681 @var{discard} is one of "ignore
" (or "off
") or "unmap
" (or "on
") and controls
682 whether @code{discard} (also known as @code{trim} or @code{unmap}) requests are
683 ignored or passed to the filesystem. Some machine types may not support
685 @item detect-zeroes=@var{detect-zeroes}
686 @var{detect-zeroes} is "off
", "on
" or "unmap
" and enables the automatic
687 conversion of plain zero writes by the OS to driver specific optimized
688 zero write commands. You may even choose "unmap
" if @var{discard} is set
689 to "unmap
" to allow a zero write to be converted to an @code{unmap} operation.
692 @item Driver-specific options for @code{file}
694 This is the protocol-level block driver for accessing regular files.
698 The path to the image file in the local filesystem
700 Specifies the AIO backend (threads/native, default: threads)
702 Specifies whether the image file is protected with Linux OFD / POSIX locks. The
703 default is to use the Linux Open File Descriptor API if available, otherwise no
704 lock is applied. (auto/on/off, default: auto)
708 -blockdev driver=file,node-name=disk,filename=disk.img
711 @item Driver-specific options for @code{raw}
713 This is the image format block driver for raw images. It is usually
714 stacked on top of a protocol level block driver such as @code{file}.
718 Reference to or definition of the data source block driver node
719 (e.g. a @code{file} driver node)
723 -blockdev driver=file,node-name=disk_file,filename=disk.img
724 -blockdev driver=raw,node-name=disk,file=disk_file
728 -blockdev driver=raw,node-name=disk,file.driver=file,file.filename=disk.img
731 @item Driver-specific options for @code{qcow2}
733 This is the image format block driver for qcow2 images. It is usually
734 stacked on top of a protocol level block driver such as @code{file}.
738 Reference to or definition of the data source block driver node
739 (e.g. a @code{file} driver node)
742 Reference to or definition of the backing file block device (default is taken
743 from the image file). It is allowed to pass an empty string here in order to
744 disable the default backing file.
747 Whether to enable the lazy refcounts feature (on/off; default is taken from the
751 The maximum total size of the L2 table and refcount block caches in bytes
752 (default: 1048576 bytes or 8 clusters, whichever is larger)
755 The maximum size of the L2 table cache in bytes
756 (default: 4/5 of the total cache size)
758 @item refcount-cache-size
759 The maximum size of the refcount block cache in bytes
760 (default: 1/5 of the total cache size)
762 @item cache-clean-interval
763 Clean unused entries in the L2 and refcount caches. The interval is in seconds.
764 The default value is 0 and it disables this feature.
766 @item pass-discard-request
767 Whether discard requests to the qcow2 device should be forwarded to the data
768 source (on/off; default: on if discard=unmap is specified, off otherwise)
770 @item pass-discard-snapshot
771 Whether discard requests for the data source should be issued when a snapshot
772 operation (e.g. deleting a snapshot) frees clusters in the qcow2 file (on/off;
775 @item pass-discard-other
776 Whether discard requests for the data source should be issued on other
777 occasions where a cluster gets freed (on/off; default: off)
780 Which overlap checks to perform for writes to the image
781 (none/constant/cached/all; default: cached). For details or finer
782 granularity control refer to the QAPI documentation of @code{blockdev-add}.
787 -blockdev driver=file,node-name=my_file,filename=/tmp/disk.qcow2
788 -blockdev driver=qcow2,node-name=hda,file=my_file,overlap-check=none,cache-size=16777216
792 -blockdev driver=qcow2,node-name=disk,file.driver=http,file.filename=http://example.com/image.qcow2
795 @item Driver-specific options for other drivers
796 Please refer to the QAPI documentation of the @code{blockdev-add} QMP command.
802 DEF("drive
", HAS_ARG, QEMU_OPTION_drive,
803 "-drive
[file
=file
][,if=type
][,bus
=n
][,unit
=m
][,media
=d
][,index
=i
]\n"
804 " [,cyls
=c
,heads
=h
,secs
=s
[,trans
=t
]][,snapshot
=on|off
]\n"
805 " [,cache
=writethrough|writeback|none|directsync|unsafe
][,format
=f
]\n"
806 " [,serial
=s
][,addr
=A
][,rerror
=ignore|stop|report
]\n"
807 " [,werror
=ignore|stop|report|enospc
][,id
=name
][,aio
=threads|native
]\n"
808 " [,readonly
=on|off
][,copy
-on
-read
=on|off
]\n"
809 " [,discard
=ignore|unmap
][,detect
-zeroes
=on|off|unmap
]\n"
810 " [[,bps
=b
]|
[[,bps_rd
=r
][,bps_wr
=w
]]]\n"
811 " [[,iops
=i
]|
[[,iops_rd
=r
][,iops_wr
=w
]]]\n"
812 " [[,bps_max
=bm
]|
[[,bps_rd_max
=rm
][,bps_wr_max
=wm
]]]\n"
813 " [[,iops_max
=im
]|
[[,iops_rd_max
=irm
][,iops_wr_max
=iwm
]]]\n"
814 " [[,iops_size
=is
]]\n"
816 " use
'file' as a drive image
\n", QEMU_ARCH_ALL)
818 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
821 Define a new drive. This includes creating a block driver node (the backend) as
822 well as a guest device, and is mostly a shortcut for defining the corresponding
823 @option{-blockdev} and @option{-device} options.
825 @option{-drive} accepts all options that are accepted by @option{-blockdev}. In
826 addition, it knows the following options:
829 @item file=@var{file}
830 This option defines which disk image (@pxref{disk_images}) to use with
831 this drive. If the filename contains comma, you must double it
832 (for instance, "file
=my
,,file
" to use file "my
,file
").
834 Special files such as iSCSI devices can be specified using protocol
835 specific URLs. See the section for "Device URL Syntax
" for more information.
836 @item if=@var{interface}
837 This option defines on which type on interface the drive is connected.
838 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio, none.
839 @item bus=@var{bus},unit=@var{unit}
840 These options define where is connected the drive by defining the bus number and
842 @item index=@var{index}
843 This option defines where is connected the drive by using an index in the list
844 of available connectors of a given interface type.
845 @item media=@var{media}
846 This option defines the type of the media: disk or cdrom.
847 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
848 Force disk physical geometry and the optional BIOS translation (trans=none or
849 lba). These parameters are deprecated, use the corresponding parameters
850 of @code{-device} instead.
851 @item snapshot=@var{snapshot}
852 @var{snapshot} is "on
" or "off
" and controls snapshot mode for the given drive
853 (see @option{-snapshot}).
854 @item cache=@var{cache}
855 @var{cache} is "none
", "writeback
", "unsafe
", "directsync
" or "writethrough
"
856 and controls how the host cache is used to access block data. This is a
857 shortcut that sets the @option{cache.direct} and @option{cache.no-flush}
858 options (as in @option{-blockdev}), and additionally @option{cache.writeback},
859 which provides a default for the @option{write-cache} option of block guest
860 devices (as in @option{-device}). The modes correspond to the following
863 @c Our texi2pod.pl script doesn't support @multitable, so fall back to using
864 @c plain ASCII art (well, UTF-8 art really). This looks okay both in the manpage
865 @c and the HTML output.
867 @ │ cache.writeback cache.direct cache.no-flush
868 ─────────────┼─────────────────────────────────────────────────
869 writeback │ on off off
871 writethrough │ off off off
872 directsync │ off on off
876 The default mode is @option{cache=writeback}.
879 @var{aio} is "threads
", or "native
" and selects between pthread based disk I/O and native Linux AIO.
880 @item format=@var{format}
881 Specify which disk @var{format} will be used rather than detecting
882 the format. Can be used to specify format=raw to avoid interpreting
883 an untrusted format header.
884 @item serial=@var{serial}
885 This option specifies the serial number to assign to the device. This
886 parameter is deprecated, use the corresponding parameter of @code{-device}
888 @item addr=@var{addr}
889 Specify the controller's PCI address (if=virtio only). This parameter is
890 deprecated, use the corresponding parameter of @code{-device} instead.
891 @item werror=@var{action},rerror=@var{action}
892 Specify which @var{action} to take on write and read errors. Valid actions are:
893 "ignore
" (ignore the error and try to continue), "stop
" (pause QEMU),
894 "report
" (report the error to the guest), "enospc
" (pause QEMU only if the
895 host disk is full; report the error to the guest otherwise).
896 The default setting is @option{werror=enospc} and @option{rerror=report}.
897 @item copy-on-read=@var{copy-on-read}
898 @var{copy-on-read} is "on
" or "off
" and enables whether to copy read backing
899 file sectors into the image file.
900 @item bps=@var{b},bps_rd=@var{r},bps_wr=@var{w}
901 Specify bandwidth throttling limits in bytes per second, either for all request
902 types or for reads or writes only. Small values can lead to timeouts or hangs
903 inside the guest. A safe minimum for disks is 2 MB/s.
904 @item bps_max=@var{bm},bps_rd_max=@var{rm},bps_wr_max=@var{wm}
905 Specify bursts in bytes per second, either for all request types or for reads
906 or writes only. Bursts allow the guest I/O to spike above the limit
908 @item iops=@var{i},iops_rd=@var{r},iops_wr=@var{w}
909 Specify request rate limits in requests per second, either for all request
910 types or for reads or writes only.
911 @item iops_max=@var{bm},iops_rd_max=@var{rm},iops_wr_max=@var{wm}
912 Specify bursts in requests per second, either for all request types or for reads
913 or writes only. Bursts allow the guest I/O to spike above the limit
915 @item iops_size=@var{is}
916 Let every @var{is} bytes of a request count as a new request for iops
917 throttling purposes. Use this option to prevent guests from circumventing iops
918 limits by sending fewer but larger requests.
920 Join a throttling quota group with given name @var{g}. All drives that are
921 members of the same group are accounted for together. Use this option to
922 prevent guests from circumventing throttling limits by using many small disks
923 instead of a single larger disk.
926 By default, the @option{cache.writeback=on} mode is used. It will report data
927 writes as completed as soon as the data is present in the host page cache.
928 This is safe as long as your guest OS makes sure to correctly flush disk caches
929 where needed. If your guest OS does not handle volatile disk write caches
930 correctly and your host crashes or loses power, then the guest may experience
933 For such guests, you should consider using @option{cache.writeback=off}. This
934 means that the host page cache will be used to read and write data, but write
935 notification will be sent to the guest only after QEMU has made sure to flush
936 each write to the disk. Be aware that this has a major impact on performance.
938 When using the @option{-snapshot} option, unsafe caching is always used.
940 Copy-on-read avoids accessing the same backing file sectors repeatedly and is
941 useful when the backing file is over a slow network. By default copy-on-read
944 Instead of @option{-cdrom} you can use:
946 qemu-system-i386 -drive file=file,index=2,media=cdrom
949 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
952 qemu-system-i386 -drive file=file,index=0,media=disk
953 qemu-system-i386 -drive file=file,index=1,media=disk
954 qemu-system-i386 -drive file=file,index=2,media=disk
955 qemu-system-i386 -drive file=file,index=3,media=disk
958 You can open an image using pre-opened file descriptors from an fd set:
961 -add-fd fd=3,set=2,opaque="rdwr
:/path
/to
/file
"
962 -add-fd fd=4,set=2,opaque="rdonly
:/path
/to
/file
"
963 -drive file=/dev/fdset/2,index=0,media=disk
966 You can connect a CDROM to the slave of ide0:
968 qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
971 If you don't specify the "file
=" argument, you define an empty drive:
973 qemu-system-i386 -drive if=ide,index=1,media=cdrom
976 Instead of @option{-fda}, @option{-fdb}, you can use:
978 qemu-system-i386 -drive file=file,index=0,if=floppy
979 qemu-system-i386 -drive file=file,index=1,if=floppy
982 By default, @var{interface} is "ide
" and @var{index} is automatically
985 qemu-system-i386 -drive file=a -drive file=b"
989 qemu
-system
-i386
-hda a
-hdb b
993 DEF("mtdblock", HAS_ARG
, QEMU_OPTION_mtdblock
,
994 "-mtdblock file use 'file' as on-board Flash memory image\n",
997 @item
-mtdblock @
var{file
}
999 Use @
var{file
} as on
-board Flash memory image
.
1002 DEF("sd", HAS_ARG
, QEMU_OPTION_sd
,
1003 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL
)
1005 @item
-sd @
var{file
}
1007 Use @
var{file
} as SecureDigital card image
.
1010 DEF("pflash", HAS_ARG
, QEMU_OPTION_pflash
,
1011 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL
)
1013 @item
-pflash @
var{file
}
1015 Use @
var{file
} as a parallel flash image
.
1018 DEF("snapshot", 0, QEMU_OPTION_snapshot
,
1019 "-snapshot write to temporary files instead of disk image files\n",
1024 Write to temporary files instead of disk image files
. In
this case,
1025 the raw disk image you use is not written back
. You can however force
1026 the write back by pressing @key
{C
-a s
} (@pxref
{disk_images
}).
1029 DEF("fsdev", HAS_ARG
, QEMU_OPTION_fsdev
,
1030 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
1031 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n"
1032 " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n"
1033 " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n"
1034 " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n"
1035 " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n"
1036 " [[,throttling.iops-size=is]]\n",
1041 @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
}]
1043 Define a
new file system device
. Valid options are
:
1045 @item @
var{fsdriver
}
1046 This option specifies the fs driver backend to use
.
1047 Currently
"local", "handle" and
"proxy" file system drivers are supported
.
1049 Specifies identifier
for this device
1050 @item path
=@
var{path
}
1051 Specifies the export path
for the file system device
. Files under
1052 this path will be available to the
9p client on the guest
.
1053 @item security_model
=@
var{security_model
}
1054 Specifies the security model to be used
for this export path
.
1055 Supported security models are
"passthrough", "mapped-xattr", "mapped-file" and
"none".
1056 In
"passthrough" security model
, files are stored
using the same
1057 credentials as they are created on the guest
. This requires QEMU
1058 to run as root
. In
"mapped-xattr" security model
, some of the file
1059 attributes like uid
, gid
, mode bits and link target are stored as
1060 file attributes
. For
"mapped-file" these attributes are stored
in the
1061 hidden
.virtfs_metadata directory
. Directories exported by
this security model cannot
1062 interact with other unix tools
. "none" security model is same as
1063 passthrough except the sever won
't report failures if it fails to
1064 set file attributes like ownership. Security model is mandatory
1065 only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
1066 security model as a parameter
.
1067 @item writeout
=@
var{writeout
}
1068 This is an optional argument
. The only supported value is
"immediate".
1069 This means that host page cache will be used to read and write data but
1070 write notification will be sent to the guest only when the data has been
1071 reported as written by the storage subsystem
.
1073 Enables exporting
9p share as a readonly mount
for guests
. By
default
1074 read
-write access is given
.
1075 @item socket
=@
var{socket
}
1076 Enables proxy filesystem driver to use passed socket file
for communicating
1077 with virtfs
-proxy
-helper
1078 @item sock_fd
=@
var{sock_fd
}
1079 Enables proxy filesystem driver to use passed socket descriptor
for
1080 communicating with virtfs
-proxy
-helper
. Usually a helper like libvirt
1081 will create socketpair and pass one of the fds as sock_fd
1082 @item fmode
=@
var{fmode
}
1083 Specifies the
default mode
for newly created files on the host
. Works only
1084 with security models
"mapped-xattr" and
"mapped-file".
1085 @item dmode
=@
var{dmode
}
1086 Specifies the
default mode
for newly created directories on the host
. Works
1087 only with security models
"mapped-xattr" and
"mapped-file".
1090 -fsdev option is used along with
-device driver
"virtio-9p-pci".
1091 @item
-device virtio
-9p
-pci
,fsdev
=@
var{id
},mount_tag
=@
var{mount_tag
}
1092 Options
for virtio
-9p
-pci driver are
:
1094 @item fsdev
=@
var{id
}
1095 Specifies the id value specified along with
-fsdev option
1096 @item mount_tag
=@
var{mount_tag
}
1097 Specifies the tag name to be used by the guest to mount
this export point
1102 DEF("virtfs", HAS_ARG
, QEMU_OPTION_virtfs
,
1103 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
1104 " [,id=id][,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n",
1109 @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
}]
1112 The general form of a Virtual File system pass
-through options are
:
1114 @item @
var{fsdriver
}
1115 This option specifies the fs driver backend to use
.
1116 Currently
"local", "handle" and
"proxy" file system drivers are supported
.
1118 Specifies identifier
for this device
1119 @item path
=@
var{path
}
1120 Specifies the export path
for the file system device
. Files under
1121 this path will be available to the
9p client on the guest
.
1122 @item security_model
=@
var{security_model
}
1123 Specifies the security model to be used
for this export path
.
1124 Supported security models are
"passthrough", "mapped-xattr", "mapped-file" and
"none".
1125 In
"passthrough" security model
, files are stored
using the same
1126 credentials as they are created on the guest
. This requires QEMU
1127 to run as root
. In
"mapped-xattr" security model
, some of the file
1128 attributes like uid
, gid
, mode bits and link target are stored as
1129 file attributes
. For
"mapped-file" these attributes are stored
in the
1130 hidden
.virtfs_metadata directory
. Directories exported by
this security model cannot
1131 interact with other unix tools
. "none" security model is same as
1132 passthrough except the sever won
't report failures if it fails to
1133 set file attributes like ownership. Security model is mandatory only
1134 for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
1135 model as a parameter
.
1136 @item writeout
=@
var{writeout
}
1137 This is an optional argument
. The only supported value is
"immediate".
1138 This means that host page cache will be used to read and write data but
1139 write notification will be sent to the guest only when the data has been
1140 reported as written by the storage subsystem
.
1142 Enables exporting
9p share as a readonly mount
for guests
. By
default
1143 read
-write access is given
.
1144 @item socket
=@
var{socket
}
1145 Enables proxy filesystem driver to use passed socket file
for
1146 communicating with virtfs
-proxy
-helper
. Usually a helper like libvirt
1147 will create socketpair and pass one of the fds as sock_fd
1149 Enables proxy filesystem driver to use passed
'sock_fd' as the socket
1150 descriptor
for interfacing with virtfs
-proxy
-helper
1151 @item fmode
=@
var{fmode
}
1152 Specifies the
default mode
for newly created files on the host
. Works only
1153 with security models
"mapped-xattr" and
"mapped-file".
1154 @item dmode
=@
var{dmode
}
1155 Specifies the
default mode
for newly created directories on the host
. Works
1156 only with security models
"mapped-xattr" and
"mapped-file".
1160 DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth
,
1161 "-virtfs_synth Create synthetic file system image\n",
1165 @findex
-virtfs_synth
1166 Create synthetic file system image
1169 DEF("iscsi", HAS_ARG
, QEMU_OPTION_iscsi
,
1170 "-iscsi [user=user][,password=password]\n"
1171 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
1172 " [,initiator-name=initiator-iqn][,id=target-iqn]\n"
1173 " [,timeout=timeout]\n"
1174 " iSCSI session parameters\n", QEMU_ARCH_ALL
)
1179 Configure iSCSI session parameters
.
1187 DEFHEADING(USB options
:)
1192 DEF("usb", 0, QEMU_OPTION_usb
,
1193 "-usb enable the USB driver (if it is not used by default yet)\n",
1198 Enable the USB
driver (if it is not used by
default yet
).
1201 DEF("usbdevice", HAS_ARG
, QEMU_OPTION_usbdevice
,
1202 "-usbdevice name add the host or guest USB device 'name'\n",
1206 @item
-usbdevice @
var{devname
}
1208 Add the USB device @
var{devname
}. Note that
this option is deprecated
,
1209 please use @code
{-device usb
-...} instead
. @xref
{usb_devices
}.
1214 Virtual Mouse
. This will
override the PS
/2 mouse emulation when activated
.
1217 Pointer device that uses absolute
coordinates (like a touchscreen
). This
1218 means QEMU is able to report the mouse position without having to grab the
1219 mouse
. Also overrides the PS
/2 mouse emulation when activated
.
1222 Braille device
. This will use BrlAPI to display the braille output on a real
1233 DEFHEADING(Display options
:)
1238 DEF("display", HAS_ARG
, QEMU_OPTION_display
,
1239 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
1240 " [,window_close=on|off][,gl=on|off]\n"
1241 "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n"
1242 "-display vnc=<display>[,<optargs>]\n"
1245 " select display type\n"
1246 "The default display is equivalent to\n"
1247 #
if defined(CONFIG_GTK
)
1248 "\t\"-display gtk\"\n"
1249 #elif
defined(CONFIG_SDL
)
1250 "\t\"-display sdl\"\n"
1251 #elif
defined(CONFIG_COCOA
)
1252 "\t\"-display cocoa\"\n"
1253 #elif
defined(CONFIG_VNC
)
1254 "\t\"-vnc localhost:0,to=99,id=default\"\n"
1256 "\t\"-display none\"\n"
1260 @item
-display @
var{type
}
1262 Select type of display to use
. This option is a replacement
for the
1263 old style
-sdl
/-curses
/... options
. Valid values
for @
var{type
} are
1266 Display video output via
SDL (usually
in a separate graphics
1267 window
; see the SDL documentation
for other possibilities
).
1269 Display video output via curses
. For graphics device models which
1270 support a text mode
, QEMU can display
this output
using a
1271 curses
/ncurses
interface. Nothing is displayed when the graphics
1272 device is
in graphical mode or
if the graphics device does not support
1273 a text mode
. Generally only the VGA device models support text mode
.
1275 Do not display video output
. The guest will still see an emulated
1276 graphics card
, but its output will not be displayed to the QEMU
1277 user
. This option differs from the
-nographic option
in that it
1278 only affects what is done with video output
; -nographic also changes
1279 the destination of the serial and parallel port data
.
1281 Display video output
in a GTK window
. This
interface provides drop
-down
1282 menus and other UI elements to configure and control the VM during
1285 Start a VNC server on display
<arg
>
1289 DEF("nographic", 0, QEMU_OPTION_nographic
,
1290 "-nographic disable graphical output and redirect serial I/Os to console\n",
1295 Normally
, if QEMU is compiled with graphical window support
, it displays
1296 output such as guest graphics
, guest console
, and the QEMU monitor
in a
1297 window
. With
this option
, you can totally disable graphical output so
1298 that QEMU is a simple command line application
. The emulated serial port
1299 is redirected on the console and muxed with the
monitor (unless
1300 redirected elsewhere explicitly
). Therefore
, you can still use QEMU to
1301 debug a Linux kernel with a serial console
. Use @key
{C
-a h
} for help on
1302 switching between the console and monitor
.
1305 DEF("curses", 0, QEMU_OPTION_curses
,
1306 "-curses shorthand for -display curses\n",
1311 Normally
, if QEMU is compiled with graphical window support
, it displays
1312 output such as guest graphics
, guest console
, and the QEMU monitor
in a
1313 window
. With
this option
, QEMU can display the VGA output when
in text
1314 mode
using a curses
/ncurses
interface. Nothing is displayed
in graphical
1318 DEF("no-frame", 0, QEMU_OPTION_no_frame
,
1319 "-no-frame open SDL window without a frame and window decorations\n",
1324 Do not use decorations
for SDL windows and start them
using the whole
1325 available screen space
. This makes the
using QEMU
in a dedicated desktop
1326 workspace more convenient
.
1329 DEF("alt-grab", 0, QEMU_OPTION_alt_grab
,
1330 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
1335 Use Ctrl
-Alt
-Shift to grab
mouse (instead of Ctrl
-Alt
). Note that
this also
1336 affects the special
keys (for fullscreen
, monitor
-mode switching
, etc
).
1339 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab
,
1340 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
1345 Use Right
-Ctrl to grab
mouse (instead of Ctrl
-Alt
). Note that
this also
1346 affects the special
keys (for fullscreen
, monitor
-mode switching
, etc
).
1349 DEF("no-quit", 0, QEMU_OPTION_no_quit
,
1350 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL
)
1354 Disable SDL window close capability
.
1357 DEF("sdl", 0, QEMU_OPTION_sdl
,
1358 "-sdl shorthand for -display sdl\n", QEMU_ARCH_ALL
)
1365 DEF("spice", HAS_ARG
, QEMU_OPTION_spice
,
1366 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
1367 " [,x509-key-file=<file>][,x509-key-password=<file>]\n"
1368 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
1369 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n"
1370 " [,tls-ciphers=<list>]\n"
1371 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
1372 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
1373 " [,sasl][,password=<secret>][,disable-ticketing]\n"
1374 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
1375 " [,jpeg-wan-compression=[auto|never|always]]\n"
1376 " [,zlib-glz-wan-compression=[auto|never|always]]\n"
1377 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
1378 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
1379 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
1380 " [,gl=[on|off]][,rendernode=<file>]\n"
1382 " at least one of {port, tls-port} is mandatory\n",
1385 @item
-spice @
var{option
}[,@
var{option
}[,...]]
1387 Enable the spice remote desktop protocol
. Valid options are
1392 Set the TCP port spice is listening on
for plaintext channels
.
1395 Set the IP address spice is listening on
. Default is any address
.
1400 Force
using the specified IP version
.
1402 @item password
=<secret
>
1403 Set the password you need to authenticate
.
1406 Require that the client use SASL to authenticate with the spice
.
1407 The exact choice of authentication method used is controlled from the
1408 system
/ user
's SASL configuration file for the 'qemu
' service. This
1409 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1410 unprivileged user, an environment variable SASL_CONF_PATH can be used
1411 to make it search alternate locations for the service config.
1412 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1413 it is recommended that SASL always be combined with the 'tls
' and
1414 'x509
' settings to enable use of SSL and server certificates. This
1415 ensures a data encryption preventing compromise of authentication
1418 @item disable-ticketing
1419 Allow client connects without authentication.
1421 @item disable-copy-paste
1422 Disable copy paste between the client and the guest.
1424 @item disable-agent-file-xfer
1425 Disable spice-vdagent based file-xfer between the client and the guest.
1428 Set the TCP port spice is listening on for encrypted channels.
1430 @item x509-dir=<dir>
1431 Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1433 @item x509-key-file=<file>
1434 @itemx x509-key-password=<file>
1435 @itemx x509-cert-file=<file>
1436 @itemx x509-cacert-file=<file>
1437 @itemx x509-dh-key-file=<file>
1438 The x509 file names can also be configured individually.
1440 @item tls-ciphers=<list>
1441 Specify which ciphers to use.
1443 @item tls-channel=[main|display|cursor|inputs|record|playback]
1444 @itemx plaintext-channel=[main|display|cursor|inputs|record|playback]
1445 Force specific channel to be used with or without TLS encryption. The
1446 options can be specified multiple times to configure multiple
1447 channels. The special name "default" can be used to set the default
1448 mode. For channels which are not explicitly forced into one mode the
1449 spice client is allowed to pick tls/plaintext as he pleases.
1451 @item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1452 Configure image compression (lossless).
1453 Default is auto_glz.
1455 @item jpeg-wan-compression=[auto|never|always]
1456 @itemx zlib-glz-wan-compression=[auto|never|always]
1457 Configure wan image compression (lossy for slow links).
1460 @item streaming-video=[off|all|filter]
1461 Configure video stream detection. Default is off.
1463 @item agent-mouse=[on|off]
1464 Enable/disable passing mouse events via vdagent. Default is on.
1466 @item playback-compression=[on|off]
1467 Enable/disable audio stream compression (using celt 0.5.1). Default is on.
1469 @item seamless-migration=[on|off]
1470 Enable/disable spice seamless migration. Default is off.
1473 Enable/disable OpenGL context. Default is off.
1475 @item rendernode=<file>
1476 DRM render node for OpenGL rendering. If not specified, it will pick
1477 the first available. (Since 2.9)
1482 DEF("portrait", 0, QEMU_OPTION_portrait,
1483 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
1488 Rotate graphical output 90 deg left (only PXA LCD).
1491 DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1492 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
1495 @item -rotate @var{deg}
1497 Rotate graphical output some deg left (only PXA LCD).
1500 DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1501 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n"
1502 " select video card type\n", QEMU_ARCH_ALL)
1504 @item -vga @var{type}
1506 Select type of VGA card to emulate. Valid values for @var{type} are
1509 Cirrus Logic GD5446 Video card. All Windows versions starting from
1510 Windows 95 should recognize and use this graphic card. For optimal
1511 performances, use 16 bit color depth in the guest and the host OS.
1512 (This card was the default before QEMU 2.2)
1514 Standard VGA card with Bochs VBE extensions. If your guest OS
1515 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1516 to use high resolution modes (>= 1280x1024x16) then you should use
1517 this option. (This card is the default since QEMU 2.2)
1519 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1520 recent XFree86/XOrg server or Windows guest with a driver for this
1523 QXL paravirtual graphic card. It is VGA compatible (including VESA
1524 2.0 VBE support). Works best with qxl guest drivers installed though.
1525 Recommended choice when using the spice protocol.
1527 (sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1528 sun4m machines and offers both 8-bit and 24-bit colour depths at a
1529 fixed resolution of 1024x768.
1531 (sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1532 for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1533 resolutions aimed at people wishing to run older Solaris versions.
1541 DEF("full-screen", 0, QEMU_OPTION_full_screen,
1542 "-full-screen start in full screen\n", QEMU_ARCH_ALL)
1545 @findex -full-screen
1546 Start in full screen.
1549 DEF("g", 1, QEMU_OPTION_g ,
1550 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
1551 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1553 @item -g @var{width}x@var{height}[x@var{depth}]
1555 Set the initial graphical resolution and depth (PPC, SPARC only).
1558 DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1559 "-vnc <display> shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL)
1561 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1563 Normally, if QEMU is compiled with graphical window support, it displays
1564 output such as guest graphics, guest console, and the QEMU monitor in a
1565 window. With this option, you can have QEMU listen on VNC display
1566 @var{display} and redirect the VGA display over the VNC session. It is
1567 very useful to enable the usb tablet device when using this option
1568 (option @option{-device usb-tablet}). When using the VNC display, you
1569 must use the @option{-k} parameter to set the keyboard layout if you are
1570 not using en-us. Valid syntax for the @var{display} is
1576 With this option, QEMU will try next available VNC @var{display}s, until the
1577 number @var{L}, if the origianlly defined "-vnc @var{display}" is not
1578 available, e.g. port 5900+@var{display} is already used by another
1579 application. By default, to=0.
1581 @item @var{host}:@var{d}
1583 TCP connections will only be allowed from @var{host} on display @var{d}.
1584 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1585 be omitted in which case the server will accept connections from any host.
1587 @item unix:@var{path}
1589 Connections will be allowed over UNIX domain sockets where @var{path} is the
1590 location of a unix socket to listen for connections on.
1594 VNC is initialized but not started. The monitor @code{change} command
1595 can be used to later start the VNC server.
1599 Following the @var{display} value there may be one or more @var{option} flags
1600 separated by commas. Valid options are
1606 Connect to a listening VNC client via a ``reverse'' connection. The
1607 client is specified by the @var{display}. For reverse network
1608 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1609 is a TCP port number, not a display number.
1613 Opens an additional TCP listening port dedicated to VNC Websocket connections.
1614 If a bare @var{websocket} option is given, the Websocket port is
1615 5700+@var{display}. An alternative port can be specified with the
1616 syntax @code{websocket}=@var{port}.
1618 If @var{host} is specified connections will only be allowed from this host.
1619 It is possible to control the websocket listen address independently, using
1620 the syntax @code{websocket}=@var{host}:@var{port}.
1622 If no TLS credentials are provided, the websocket connection runs in
1623 unencrypted mode. If TLS credentials are provided, the websocket connection
1624 requires encrypted client connections.
1628 Require that password based authentication is used for client connections.
1630 The password must be set separately using the @code{set_password} command in
1631 the @ref{pcsys_monitor}. The syntax to change your password is:
1632 @code{set_password <protocol> <password>} where <protocol> could be either
1635 If you would like to change <protocol> password expiration, you should use
1636 @code{expire_password <protocol> <expiration-time>} where expiration time could
1637 be one of the following options: now, never, +seconds or UNIX time of
1638 expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1639 to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1642 You can also use keywords "now" or "never" for the expiration time to
1643 allow <protocol> password to expire immediately or never expire.
1645 @item tls-creds=@var{ID}
1647 Provides the ID of a set of TLS credentials to use to secure the
1648 VNC server. They will apply to both the normal VNC server socket
1649 and the websocket socket (if enabled). Setting TLS credentials
1650 will cause the VNC server socket to enable the VeNCrypt auth
1651 mechanism. The credentials should have been previously created
1652 using the @option{-object tls-creds} argument.
1654 The @option{tls-creds} parameter obsoletes the @option{tls},
1655 @option{x509}, and @option{x509verify} options, and as such
1656 it is not permitted to set both new and old type options at
1661 Require that client use TLS when communicating with the VNC server. This
1662 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1663 attack. It is recommended that this option be combined with either the
1664 @option{x509} or @option{x509verify} options.
1666 This option is now deprecated in favor of using the @option{tls-creds}
1669 @item x509=@var{/path/to/certificate/dir}
1671 Valid if @option{tls} is specified. Require that x509 credentials are used
1672 for negotiating the TLS session. The server will send its x509 certificate
1673 to the client. It is recommended that a password be set on the VNC server
1674 to provide authentication of the client when this is used. The path following
1675 this option specifies where the x509 certificates are to be loaded from.
1676 See the @ref{vnc_security} section for details on generating certificates.
1678 This option is now deprecated in favour of using the @option{tls-creds}
1681 @item x509verify=@var{/path/to/certificate/dir}
1683 Valid if @option{tls} is specified. Require that x509 credentials are used
1684 for negotiating the TLS session. The server will send its x509 certificate
1685 to the client, and request that the client send its own x509 certificate.
1686 The server will validate the client's certificate against the CA certificate
,
1687 and reject clients when validation fails
. If the certificate authority is
1688 trusted
, this is a sufficient authentication mechanism
. You may still wish
1689 to set a password on the VNC server as a second authentication layer
. The
1690 path following
this option specifies where the x509 certificates are to
1691 be loaded from
. See the @ref
{vnc_security
} section
for details on generating
1694 This option is now deprecated
in favour of
using the @option
{tls
-creds
}
1699 Require that the client use SASL to authenticate with the VNC server
.
1700 The exact choice of authentication method used is controlled from the
1701 system
/ user
's SASL configuration file for the 'qemu
' service. This
1702 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1703 unprivileged user, an environment variable SASL_CONF_PATH can be used
1704 to make it search alternate locations for the service config.
1705 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1706 it is recommended that SASL always be combined with the 'tls
' and
1707 'x509
' settings to enable use of SSL and server certificates. This
1708 ensures a data encryption preventing compromise of authentication
1709 credentials. See the @ref{vnc_security} section for details on using
1710 SASL authentication.
1714 Turn on access control lists for checking of the x509 client certificate
1715 and SASL party. For x509 certs, the ACL check is made against the
1716 certificate's distinguished name
. This is something that looks like
1717 @code
{C
=GB
,O
=ACME
,L
=Boston
,CN
=bob
}. For SASL party
, the ACL check is
1718 made against the username
, which depending on the SASL plugin
, may
1719 include a realm component
, eg @code
{bob
} or @code
{bob@@EXAMPLE
.COM
}.
1720 When the @option
{acl
} flag is set
, the initial access list will be
1721 empty
, with a @code
{deny
} policy
. Thus no one will be allowed to
1722 use the VNC server until the ACLs have been loaded
. This can be
1723 achieved
using the @code
{acl
} monitor command
.
1727 Enable lossy compression
methods (gradient
, JPEG
, ...). If
this
1728 option is set
, VNC client may receive lossy framebuffer updates
1729 depending on its encoding settings
. Enabling
this option can save
1730 a lot of bandwidth at the expense of quality
.
1734 Disable adaptive encodings
. Adaptive encodings are enabled by
default.
1735 An adaptive encoding will
try to detect frequently updated screen regions
,
1736 and send updates
in these regions
using a lossy
encoding (like JPEG
).
1737 This can be really helpful to save bandwidth when playing videos
. Disabling
1738 adaptive encodings restores the original
static behavior of encodings
1741 @item share
=[allow
-exclusive|force
-shared|ignore
]
1743 Set display sharing policy
. 'allow-exclusive' allows clients to ask
1744 for exclusive access
. As suggested by the rfb spec
this is
1745 implemented by dropping other connections
. Connecting multiple
1746 clients
in parallel requires all clients asking
for a shared session
1747 (vncviewer
: -shared
switch). This is the
default. 'force-shared'
1748 disables exclusive client access
. Useful
for shared desktop sessions
,
1749 where you don
't want someone forgetting specify -shared disconnect
1750 everybody else. 'ignore
' completely ignores the shared flag and
1751 allows everybody connect unconditionally. Doesn't conform to the rfb
1752 spec but is traditional QEMU behavior
.
1756 Set keyboard delay
, for key down and key up events
, in milliseconds
.
1757 Default is
10. Keyboards are low
-bandwidth devices
, so
this slowdown
1758 can help the device and guest to keep up and not lose events
in case
1759 events are arriving
in bulk
. Possible causes
for the latter are flaky
1760 network connections
, or scripts
for automated testing
.
1768 ARCHHEADING(, QEMU_ARCH_I386
)
1770 ARCHHEADING(i386 target only
:, QEMU_ARCH_I386
)
1775 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack
,
1776 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1781 Use it when installing Windows
2000 to avoid a disk full bug
. After
1782 Windows
2000 is installed
, you no longer need
this option (this option
1783 slows down the IDE transfers
).
1786 HXCOMM Deprecated by
-rtc
1787 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack
, "", QEMU_ARCH_I386
)
1789 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk
,
1790 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1793 @item
-no
-fd
-bootchk
1794 @findex
-no
-fd
-bootchk
1795 Disable boot signature checking
for floppy disks
in BIOS
. May
1796 be needed to boot from old floppy disks
.
1799 DEF("no-acpi", 0, QEMU_OPTION_no_acpi
,
1800 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM
)
1804 Disable
ACPI (Advanced Configuration and Power Interface
) support
. Use
1805 it
if your guest OS complains about ACPI
problems (PC target machine
1809 DEF("no-hpet", 0, QEMU_OPTION_no_hpet
,
1810 "-no-hpet disable HPET\n", QEMU_ARCH_I386
)
1814 Disable HPET support
.
1817 DEF("acpitable", HAS_ARG
, QEMU_OPTION_acpitable
,
1818 "-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"
1819 " ACPI table description\n", QEMU_ARCH_I386
)
1821 @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
}]...]
1823 Add ACPI table with specified header fields and context from specified files
.
1824 For file
=, take whole ACPI table from the specified files
, including all
1825 ACPI
headers (possible overridden by other options
).
1826 For data
=, only data
1827 portion of the table is used
, all header information is specified
in the
1829 If a SLIC table is supplied to QEMU
, then the SLIC
's oem_id and oem_table_id
1830 fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order
1831 to ensure the field matches required by the Microsoft SLIC spec and the ACPI
1835 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1836 "-smbios file=binary\n"
1837 " load SMBIOS entry from binary file\n"
1838 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1840 " specify SMBIOS type 0 fields\n"
1841 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1842 " [,uuid=uuid][,sku=str][,family=str]\n"
1843 " specify SMBIOS type 1 fields\n"
1844 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1845 " [,asset=str][,location=str]\n"
1846 " specify SMBIOS type 2 fields\n"
1847 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n"
1849 " specify SMBIOS type 3 fields\n"
1850 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n"
1851 " [,asset=str][,part=str]\n"
1852 " specify SMBIOS type 4 fields\n"
1853 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n"
1854 " [,asset=str][,part=str][,speed=%d]\n"
1855 " specify SMBIOS type 17 fields\n",
1856 QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1858 @item -smbios file=@var{binary}
1860 Load SMBIOS entry from binary file.
1862 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1863 Specify SMBIOS type 0 fields
1865 @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}]
1866 Specify SMBIOS type 1 fields
1868 @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}]
1869 Specify SMBIOS type 2 fields
1871 @item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}]
1872 Specify SMBIOS type 3 fields
1874 @item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}]
1875 Specify SMBIOS type 4 fields
1877 @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}]
1878 Specify SMBIOS type 17 fields
1886 DEFHEADING(Network options:)
1891 HXCOMM Legacy slirp options (now moved to -net user):
1893 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1894 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1895 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1897 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1901 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1903 "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n"
1904 " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n"
1905 " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n"
1906 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,tftp=dir]\n"
1907 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1909 "[,smb=dir[,smbserver=addr]]\n"
1911 " configure a user mode network backend with ID 'str
',\n"
1912 " its DHCP server and optional services\n"
1915 "-netdev tap,id=str,ifname=name\n"
1916 " configure a host TAP network backend with ID 'str
'\n"
1918 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n"
1919 " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n"
1920 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n"
1922 " configure a host TAP network backend with ID 'str
'\n"
1923 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1924 " use network scripts 'file
' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1925 " to configure it and 'dfile
' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1926 " to deconfigure it\n"
1927 " use '[down
]script
=no
' to disable script execution\n"
1928 " use network helper 'helper
' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1930 " use 'fd
=h
' to connect to an already opened TAP interface\n"
1931 " use 'fds
=x
:y
:...:z
' to connect to already opened multiqueue capable TAP interfaces\n"
1932 " use 'sndbuf
=nbytes
' to limit the size of the send buffer (the\n"
1933 " default is disabled 'sndbuf
=0' to enable flow control set 'sndbuf
=1048576')\n"
1934 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1935 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1936 " use vhost=on to enable experimental in kernel accelerator\n"
1937 " (only has effect for virtio guests which use MSIX)\n"
1938 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1939 " use 'vhostfd
=h
' to connect to an already opened vhost net device\n"
1940 " use 'vhostfds
=x
:y
:...:z to connect to multiple already opened vhost net devices
\n"
1941 " use
'queues=n' to specify the number of queues to be created
for multiqueue TAP
\n"
1942 " use
'poll-us=n' to speciy the maximum number of microseconds that could be
\n"
1943 " spent on busy polling
for vhost net
\n"
1944 "-netdev bridge
,id
=str
[,br
=bridge
][,helper
=helper
]\n"
1945 " configure a host TAP network backend with ID
'str' that is
\n"
1946 " connected to a
bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1947 " using the program
'helper (default=" DEFAULT_BRIDGE_HELPER ")\n"
1950 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n"
1951 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n"
1952 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n"
1953 " [,rxcookie=rxcookie][,offset=offset]\n"
1954 " configure a network backend with ID 'str
' connected to\n"
1955 " an Ethernet over L2TPv3 pseudowire.\n"
1956 " Linux kernel 3.3+ as well as most routers can talk\n"
1957 " L2TPv3. This transport allows connecting a VM to a VM,\n"
1958 " VM to a router and even VM to Host. It is a nearly-universal\n"
1959 " standard (RFC3391). Note - this implementation uses static\n"
1960 " pre-configured tunnels (same as the Linux kernel).\n"
1961 " use 'src
=' to specify source address\n"
1962 " use 'dst
=' to specify destination address\n"
1963 " use 'udp
=on
' to specify udp encapsulation\n"
1964 " use 'srcport
=' to specify source udp port\n"
1965 " use 'dstport
=' to specify destination udp port\n"
1966 " use 'ipv6
=on
' to force v6\n"
1967 " L2TPv3 uses cookies to prevent misconfiguration as\n"
1968 " well as a weak security measure\n"
1969 " use 'rxcookie
=0x012345678' to specify a rxcookie\n"
1970 " use 'txcookie
=0x012345678' to specify a txcookie\n"
1971 " use 'cookie64
=on
' to set cookie size to 64 bit, otherwise 32\n"
1972 " use 'counter
=off
' to force a 'cut
-down
' L2TPv3 with no counter\n"
1973 " use 'pincounter
=on
' to work around broken counter handling in peer\n"
1974 " use 'offset
=X
' to add an extra offset between header and data\n"
1976 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n"
1977 " configure a network backend to connect to another network\n"
1978 " using a socket connection\n"
1979 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1980 " configure a network backend to connect to a multicast maddr and port\n"
1981 " use 'localaddr
=addr
' to specify the host address to send packets from\n"
1982 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
1983 " configure a network backend to connect to another network\n"
1984 " using an UDP tunnel\n"
1986 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1987 " configure a network backend to connect to port 'n
' of a vde switch\n"
1988 " running on host and listening for incoming connections on 'socketpath
'.\n"
1989 " Use group 'groupname
' and mode 'octalmode
' to change default\n"
1990 " ownership and permissions for communication port.\n"
1992 #ifdef CONFIG_NETMAP
1993 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n"
1994 " attach to the existing netmap-enabled network interface 'name
', or to a\n"
1995 " VALE port (created on the fly) called 'name
' ('nmname
' is name of the \n"
1996 " netmap device, defaults to '/dev
/netmap
')\n"
1999 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n"
2000 " configure a vhost-user network, backed by a chardev 'dev
'\n"
2002 "-netdev hubport,id=str,hubid=n[,netdev=nd]\n"
2003 " configure a hub port on QEMU VLAN 'n
'\n", QEMU_ARCH_ALL)
2004 DEF("nic", HAS_ARG, QEMU_OPTION_nic,
2005 "--nic [tap|bridge|"
2015 #ifdef CONFIG_NETMAP
2021 "socket][,option][,...][mac=macaddr]\n"
2022 " initialize an on-board / default host NIC (using MAC address\n"
2023 " macaddr) and connect it to the given host network backend\n"
2024 "--nic none use it alone to have zero network devices (the default is to\n"
2025 " provided a 'user
' network connection)\n",
2027 DEF("net", HAS_ARG, QEMU_OPTION_net,
2028 "-net nic[,vlan=n][,netdev=nd][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
2029 " configure or create an on-board (or machine default) NIC and\n"
2030 " connect it either to VLAN 'n
' or the netdev 'nd
' (for pluggable\n"
2031 " NICs please use '-device devtype
,netdev
=nd
' instead)\n"
2041 #ifdef CONFIG_NETMAP
2044 "socket][,vlan=n][,option][,option][,...]\n"
2045 " old way to initialize a host network interface\n"
2046 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL)
2048 @item -net nic[,vlan=@var{n}][,netdev=@var{nd}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
2050 Configure or create an on-board (or machine default) Network Interface Card
2051 (NIC) and connect it either to VLAN @var{n} (@var{n} = 0 is the default), or
2052 to the netdev @var{nd}. The NIC is an e1000 by default on the PC
2053 target. Optionally, the MAC address can be changed to @var{mac}, the
2054 device address set to @var{addr} (PCI cards only),
2055 and a @var{name} can be assigned for use in monitor commands.
2056 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
2057 that the card should have; this option currently only affects virtio cards; set
2058 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
2059 NIC is created. QEMU can emulate several different models of network card.
2060 Valid values for @var{type} are
2061 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
2062 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
2063 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
2064 Not all devices are supported on all targets. Use @code{-net nic,model=help}
2065 for a list of available devices for your target.
2067 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
2069 @item -net user[,@var{option}][,@var{option}][,...]
2070 Use the user mode network stack which requires no administrator
2071 privilege to run. Valid options are:
2075 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
2078 @itemx name=@var{name}
2079 Assign symbolic name for use in monitor commands.
2081 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must
2082 be enabled. If neither is specified both protocols are enabled.
2084 @item net=@var{addr}[/@var{mask}]
2085 Set IP network address the guest will see. Optionally specify the netmask,
2086 either in the form a.b.c.d or as number of valid top-most bits. Default is
2089 @item host=@var{addr}
2090 Specify the guest-visible address of the host. Default is the 2nd IP in the
2091 guest network, i.e. x.x.x.2.
2093 @item ipv6-net=@var{addr}[/@var{int}]
2094 Set IPv6 network address the guest will see (default is fec0::/64). The
2095 network prefix is given in the usual hexadecimal IPv6 address
2096 notation. The prefix size is optional, and is given as the number of
2097 valid top-most bits (default is 64).
2099 @item ipv6-host=@var{addr}
2100 Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in
2101 the guest network, i.e. xxxx::2.
2103 @item restrict=on|off
2104 If this option is enabled, the guest will be isolated, i.e. it will not be
2105 able to contact the host and no guest IP packets will be routed over the host
2106 to the outside. This option does not affect any explicitly set forwarding rules.
2108 @item hostname=@var{name}
2109 Specifies the client hostname reported by the built-in DHCP server.
2111 @item dhcpstart=@var{addr}
2112 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
2113 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
2115 @item dns=@var{addr}
2116 Specify the guest-visible address of the virtual nameserver. The address must
2117 be different from the host address. Default is the 3rd IP in the guest network,
2120 @item ipv6-dns=@var{addr}
2121 Specify the guest-visible address of the IPv6 virtual nameserver. The address
2122 must be different from the host address. Default is the 3rd IP in the guest
2123 network, i.e. xxxx::3.
2125 @item dnssearch=@var{domain}
2126 Provides an entry for the domain-search list sent by the built-in
2127 DHCP server. More than one domain suffix can be transmitted by specifying
2128 this option multiple times. If supported, this will cause the guest to
2129 automatically try to append the given domain suffix(es) in case a domain name
2130 can not be resolved.
2134 qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
2137 @item tftp=@var{dir}
2138 When using the user mode network stack, activate a built-in TFTP
2139 server. The files in @var{dir} will be exposed as the root of a TFTP server.
2140 The TFTP client on the guest must be configured in binary mode (use the command
2141 @code{bin} of the Unix TFTP client).
2143 @item bootfile=@var{file}
2144 When using the user mode network stack, broadcast @var{file} as the BOOTP
2145 filename. In conjunction with @option{tftp}, this can be used to network boot
2146 a guest from a local directory.
2148 Example (using pxelinux):
2150 qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
2153 @item smb=@var{dir}[,smbserver=@var{addr}]
2154 When using the user mode network stack, activate a built-in SMB
2155 server so that Windows OSes can access to the host files in @file{@var{dir}}
2156 transparently. The IP address of the SMB server can be set to @var{addr}. By
2157 default the 4th IP in the guest network is used, i.e. x.x.x.4.
2159 In the guest Windows OS, the line:
2163 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
2164 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
2166 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
2168 Note that a SAMBA server must be installed on the host OS.
2169 QEMU was tested successfully with smbd versions from Red Hat 9,
2170 Fedora Core 3 and OpenSUSE 11.x.
2172 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
2173 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
2174 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
2175 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
2176 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
2177 be bound to a specific host interface. If no connection type is set, TCP is
2178 used. This option can be given multiple times.
2180 For example, to redirect host X11 connection from screen 1 to guest
2181 screen 0, use the following:
2185 qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
2186 # this host xterm should open in the guest X11 server
2190 To redirect telnet connections from host port 5555 to telnet port on
2191 the guest, use the following:
2195 qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
2196 telnet localhost 5555
2199 Then when you use on the host @code{telnet localhost 5555}, you
2200 connect to the guest telnet server.
2202 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
2203 @itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
2204 Forward guest TCP connections to the IP address @var{server} on port @var{port}
2205 to the character device @var{dev} or to a program executed by @var{cmd:command}
2206 which gets spawned for each connection. This option can be given multiple times.
2208 You can either use a chardev directly and have that one used throughout QEMU's
2209 lifetime
, like
in the following example
:
2212 # open
10.10.1.1:4321 on bootup
, connect
10.0.2.100:1234 to it whenever
2213 # the guest accesses it
2214 qemu
-net user
,guestfwd
=tcp
:10.0.2.100:1234-tcp
:10.10.1.1:4321 [...]
2217 Or you can execute a command on every TCP connection established by the guest
,
2218 so that QEMU behaves similar to an inetd process
for that virtual server
:
2221 # call
"netcat 10.10.1.1 4321" on every TCP connection to
10.0.2.100:1234
2222 # and connect the TCP stream to its stdin
/stdout
2223 qemu
-net
'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
2228 Note
: Legacy stand
-alone options
-tftp
, -bootp
, -smb and
-redir are still
2229 processed and applied to
-net user
. Mixing them with the
new configuration
2230 syntax gives undefined results
. Their use
for new applications is discouraged
2231 as they will be removed from future versions
.
2233 @item
-netdev tap
,id
=@
var{id
}[,fd
=@
var{h
}][,ifname
=@
var{name
}][,script
=@
var{file
}][,downscript
=@
var{dfile
}][,br
=@
var{bridge
}][,helper
=@
var{helper
}]
2234 @itemx
-net tap
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}][,ifname
=@
var{name
}][,script
=@
var{file
}][,downscript
=@
var{dfile
}][,br
=@
var{bridge
}][,helper
=@
var{helper
}]
2235 Connect the host TAP network
interface @
var{name
} to VLAN @
var{n
}.
2237 Use the network script @
var{file
} to configure it and the network script
2238 @
var{dfile
} to deconfigure it
. If @
var{name
} is not provided
, the OS
2239 automatically provides one
. The
default network configure script is
2240 @file
{/etc
/qemu
-ifup
} and the
default network deconfigure script is
2241 @file
{/etc
/qemu
-ifdown
}. Use @option
{script
=no
} or @option
{downscript
=no
}
2242 to disable script execution
.
2244 If running QEMU as an unprivileged user
, use the network helper
2245 @
var{helper
} to configure the TAP
interface and attach it to the bridge
.
2246 The
default network helper executable is @file
{/path
/to
/qemu
-bridge
-helper
}
2247 and the
default bridge device is @file
{br0
}.
2249 @option
{fd
}=@
var{h
} can be used to specify the handle of an already
2250 opened host TAP
interface.
2255 #launch a QEMU instance with the
default network script
2256 qemu
-system
-i386 linux
.img
-net nic
-net tap
2260 #launch a QEMU instance with two NICs
, each one connected
2262 qemu
-system
-i386 linux
.img \
2263 -netdev tap
,id
=nd0
,ifname
=tap0
-device e1000
,netdev
=nd0 \
2264 -netdev tap
,id
=nd1
,ifname
=tap1
-device rtl8139
,netdev
=nd1
2268 #launch a QEMU instance with the
default network helper to
2269 #connect a TAP device to bridge br0
2270 qemu
-system
-i386 linux
.img \
2271 -net nic
-net tap
,"helper=/path/to/qemu-bridge-helper"
2274 @item
-netdev bridge
,id
=@
var{id
}[,br
=@
var{bridge
}][,helper
=@
var{helper
}]
2275 @itemx
-net bridge
[,vlan
=@
var{n
}][,name
=@
var{name
}][,br
=@
var{bridge
}][,helper
=@
var{helper
}]
2276 Connect a host TAP network
interface to a host bridge device
.
2278 Use the network helper @
var{helper
} to configure the TAP
interface and
2279 attach it to the bridge
. The
default network helper executable is
2280 @file
{/path
/to
/qemu
-bridge
-helper
} and the
default bridge
2281 device is @file
{br0
}.
2286 #launch a QEMU instance with the
default network helper to
2287 #connect a TAP device to bridge br0
2288 qemu
-system
-i386 linux
.img
-net bridge
-net nic
,model
=virtio
2292 #launch a QEMU instance with the
default network helper to
2293 #connect a TAP device to bridge qemubr0
2294 qemu
-system
-i386 linux
.img
-net bridge
,br
=qemubr0
-net nic
,model
=virtio
2297 @item
-netdev socket
,id
=@
var{id
}[,fd
=@
var{h
}][,listen
=[@
var{host
}]:@
var{port
}][,connect
=@
var{host
}:@
var{port
}]
2298 @itemx
-net socket
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}] [,listen
=[@
var{host
}]:@
var{port
}][,connect
=@
var{host
}:@
var{port
}]
2300 Connect the VLAN @
var{n
} to a remote VLAN
in another QEMU virtual
2301 machine
using a TCP socket connection
. If @option
{listen
} is
2302 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 -net nic
,macaddr
=52:54:00:12:34:56 \
2312 -net socket
,listen
=:1234
2313 # connect the VLAN
0 of
this instance to the VLAN
0
2314 # of the first instance
2315 qemu
-system
-i386 linux
.img \
2316 -net nic
,macaddr
=52:54:00:12:34:57 \
2317 -net socket
,connect
=127.0.0.1:1234
2320 @item
-netdev socket
,id
=@
var{id
}[,fd
=@
var{h
}][,mcast
=@
var{maddr
}:@
var{port
}[,localaddr
=@
var{addr
}]]
2321 @itemx
-net socket
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}][,mcast
=@
var{maddr
}:@
var{port
}[,localaddr
=@
var{addr
}]]
2323 Create a VLAN @
var{n
} shared with another QEMU virtual
2324 machines
using a UDP multicast socket
, effectively making a bus
for
2325 every QEMU with same multicast address @
var{maddr
} and @
var{port
}.
2329 Several QEMU can be running on different hosts and share same
bus (assuming
2330 correct multicast setup
for these hosts
).
2332 mcast support is compatible with User Mode
Linux (argument @option
{eth@
var{N
}=mcast
}), see
2333 @url
{http
://user-mode-linux.sf.net}.
2335 Use @option
{fd
=h
} to specify an already opened UDP multicast socket
.
2340 # launch one QEMU instance
2341 qemu
-system
-i386 linux
.img \
2342 -net nic
,macaddr
=52:54:00:12:34:56 \
2343 -net socket
,mcast
=230.0.0.1:1234
2344 # launch another QEMU instance on same
"bus"
2345 qemu
-system
-i386 linux
.img \
2346 -net nic
,macaddr
=52:54:00:12:34:57 \
2347 -net socket
,mcast
=230.0.0.1:1234
2348 # launch yet another QEMU instance on same
"bus"
2349 qemu
-system
-i386 linux
.img \
2350 -net nic
,macaddr
=52:54:00:12:34:58 \
2351 -net socket
,mcast
=230.0.0.1:1234
2354 Example (User Mode Linux compat
.):
2356 # launch QEMU
instance (note mcast address selected
2358 qemu-system-i386 linux.img \
2359 -net nic,macaddr=52:54:00:12:34:56 \
2360 -net socket,mcast=239.192.168.1:1102
2362 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
2365 Example (send packets from host's
1.2.3.4):
2367 qemu
-system
-i386 linux
.img \
2368 -net nic
,macaddr
=52:54:00:12:34:56 \
2369 -net socket
,mcast
=239.192.168.1:1102,localaddr
=1.2.3.4
2372 @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
}]
2373 @itemx
-net l2tpv3
[,vlan
=@
var{n
}][,name
=@
var{name
}],src
=@
var{srcaddr
},dst
=@
var{dstaddr
}[,srcport
=@
var{srcport
}][,dstport
=@
var{dstport
}],txsession
=@
var{txsession
}[,rxsession
=@
var{rxsession
}][,ipv6
][,udp
][,cookie64
][,counter
][,pincounter
][,txcookie
=@
var{txcookie
}][,rxcookie
=@
var{rxcookie
}][,offset
=@
var{offset
}]
2374 Connect VLAN @
var{n
} to L2TPv3 pseudowire
. L2TPv3 (RFC3391
) is a popular
2375 protocol to transport
Ethernet (and other Layer
2) data frames between
2376 two systems
. It is present
in routers
, firewalls and the Linux kernel
2377 (from version
3.3 onwards
).
2379 This transport allows a VM to communicate to another VM
, router or firewall directly
.
2382 @item src
=@
var{srcaddr
}
2383 source
address (mandatory
)
2384 @item dst
=@
var{dstaddr
}
2385 destination
address (mandatory
)
2387 select udp
encapsulation (default is ip
).
2388 @item srcport
=@
var{srcport
}
2390 @item dstport
=@
var{dstport
}
2391 destination udp port
.
2393 force v6
, otherwise defaults to v4
.
2394 @item rxcookie
=@
var{rxcookie
}
2395 @itemx txcookie
=@
var{txcookie
}
2396 Cookies are a weak form of security
in the l2tpv3 specification
.
2397 Their
function is mostly to prevent misconfiguration
. By
default they are
32
2400 Set cookie size to
64 bit instead of the
default 32
2402 Force a
'cut-down' L2TPv3 with no counter as
in
2403 draft
-mkonstan
-l2tpext
-keyed
-ipv6
-tunnel
-00
2405 Work around broken counter handling
in peer
. This may also help on
2406 networks which have packet reorder
.
2407 @item offset
=@
var{offset
}
2408 Add an extra offset between header and data
2411 For example
, to attach a VM running on host
4.3.2.1 via L2TPv3 to the bridge br
-lan
2412 on the remote Linux host
1.2.3.4:
2414 # Setup tunnel on linux host
using raw ip as encapsulation
2416 ip l2tp add tunnel remote
4.3.2.1 local
1.2.3.4 tunnel_id
1 peer_tunnel_id
1 \
2417 encap udp udp_sport
16384 udp_dport
16384
2418 ip l2tp add session tunnel_id
1 name vmtunnel0 session_id \
2419 0xFFFFFFFF peer_session_id
0xFFFFFFFF
2420 ifconfig vmtunnel0 mtu
1500
2421 ifconfig vmtunnel0 up
2422 brctl addif br
-lan vmtunnel0
2426 # launch QEMU instance
- if your network has reorder or is very lossy add
,pincounter
2428 qemu
-system
-i386 linux
.img
-net nic
-net l2tpv3
,src
=4.2.3.1,dst
=1.2.3.4,udp
,srcport
=16384,dstport
=16384,rxsession
=0xffffffff,txsession
=0xffffffff,counter
2433 @item
-netdev vde
,id
=@
var{id
}[,sock
=@
var{socketpath
}][,port
=@
var{n
}][,group
=@
var{groupname
}][,mode
=@
var{octalmode
}]
2434 @itemx
-net vde
[,vlan
=@
var{n
}][,name
=@
var{name
}][,sock
=@
var{socketpath
}] [,port
=@
var{n
}][,group
=@
var{groupname
}][,mode
=@
var{octalmode
}]
2435 Connect VLAN @
var{n
} to PORT @
var{n
} of a vde
switch running on host and
2436 listening
for incoming connections on @
var{socketpath
}. Use GROUP @
var{groupname
}
2437 and MODE @
var{octalmode
} to change
default ownership and permissions
for
2438 communication port
. This option is only available
if QEMU has been compiled
2439 with vde support enabled
.
2444 vde_switch
-F
-sock
/tmp
/myswitch
2445 # launch QEMU instance
2446 qemu
-system
-i386 linux
.img
-net nic
-net vde
,sock
=/tmp
/myswitch
2449 @item
-netdev hubport
,id
=@
var{id
},hubid
=@
var{hubid
}[,netdev
=@
var{nd
}]
2451 Create a hub port on QEMU
"vlan" @
var{hubid
}.
2453 The hubport netdev lets you connect a NIC to a QEMU
"vlan" instead of a single
2454 netdev
. @code
{-net
} and @code
{-device
} with parameter @option
{vlan
} create the
2455 required hub automatically
. Alternatively
, you can also connect the hubport
2456 to another netdev with ID @
var{nd
} by
using the @option
{netdev
=@
var{nd
}}
2459 @item
-netdev vhost
-user
,chardev
=@
var{id
}[,vhostforce
=on|off
][,queues
=n
]
2461 Establish a vhost
-user netdev
, backed by a chardev @
var{id
}. The chardev should
2462 be a unix domain socket backed one
. The vhost
-user uses a specifically defined
2463 protocol to pass vhost ioctl replacement messages to an application on the other
2464 end of the socket
. On non
-MSIX guests
, the feature can be forced with
2465 @
var{vhostforce
}. Use
'queues=@var{n}' to specify the number of queues to
2466 be created
for multiqueue vhost
-user
.
2470 qemu
-m
512 -object memory
-backend
-file
,id
=mem
,size
=512M
,mem
-path
=/hugetlbfs
,share
=on \
2471 -numa node
,memdev
=mem \
2472 -chardev socket
,id
=chr0
,path
=/path
/to
/socket \
2473 -netdev type
=vhost
-user
,id
=net0
,chardev
=chr0 \
2474 -device virtio
-net
-pci
,netdev
=net0
2477 @item
--nic
[tap|bridge|user|l2tpv3|vde|netmap|vhost
-user|socket
][,...][,mac
=macaddr
]
2479 This option is a shortcut
for setting both
, the on
-board (default) guest NIC
2480 hardware and the host network backend
in one go
. The host backend options are
2481 the same as with the corresponding @option
{--netdev
} option
. The guest NIC
2482 hardware MAC address can be set with @option
{mac
=@
var{macaddr
}}.
2485 Indicate that no network devices should be configured
. It is used to
override
2486 the
default configuration (default NIC with @option
{--net user
} backend
) which
2487 is activated
if no other networking options are provided
.
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("S", 0, QEMU_OPTION_S
, \
3306 "-S freeze CPU at startup (use 'c' to start execution)\n",
3311 Do not start CPU at
startup (you must type
'c' in the monitor
).
3314 DEF("realtime", HAS_ARG
, QEMU_OPTION_realtime
,
3315 "-realtime [mlock=on|off]\n"
3316 " run qemu with realtime features\n"
3317 " mlock=on|off controls mlock support (default: on)\n",
3320 @item
-realtime mlock
=on|off
3322 Run qemu with realtime features
.
3323 mlocking qemu and guest memory can be enabled via @option
{mlock
=on
}
3324 (enabled by
default).
3327 DEF("gdb", HAS_ARG
, QEMU_OPTION_gdb
, \
3328 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL
)
3330 @item
-gdb @
var{dev
}
3332 Wait
for gdb connection on device @
var{dev
} (@pxref
{gdb_usage
}). Typical
3333 connections will likely be TCP
-based
, but also UDP
, pseudo TTY
, or even
3334 stdio are reasonable use
case. The latter is allowing to start QEMU from
3335 within gdb and establish the connection via a pipe
:
3337 (gdb
) target remote | exec qemu
-system
-i386
-gdb stdio
...
3341 DEF("s", 0, QEMU_OPTION_s
, \
3342 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT
"\n",
3347 Shorthand
for -gdb tcp
::1234, i
.e
. open a gdbserver on TCP port
1234
3348 (@pxref
{gdb_usage
}).
3351 DEF("d", HAS_ARG
, QEMU_OPTION_d
, \
3352 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n",
3355 @item
-d @
var{item1
}[,...]
3357 Enable logging of specified items
. Use
'-d help' for a list of log items
.
3360 DEF("D", HAS_ARG
, QEMU_OPTION_D
, \
3361 "-D logfile output log to logfile (default stderr)\n",
3364 @item
-D @
var{logfile
}
3366 Output log
in @
var{logfile
} instead of to stderr
3369 DEF("dfilter", HAS_ARG
, QEMU_OPTION_DFILTER
, \
3370 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n",
3373 @item
-dfilter @
var{range1
}[,...]
3375 Filter debug output to that relevant to a range of target addresses
. The filter
3376 spec can be either @
var{start
}+@
var{size
}, @
var{start
}-@
var{size
} or
3377 @
var{start
}..@
var{end
} where @
var{start
} @
var{end
} and @
var{size
} are the
3378 addresses and sizes required
. For example
:
3380 -dfilter
0x8000..0x8fff
,0xffffffc000080000+0x200,0xffffffc000060000-0x1000
3382 Will dump output
for any code
in the
0x1000 sized block starting at
0x8000 and
3383 the
0x200 sized block starting at
0xffffffc000080000 and another
0x1000 sized
3384 block starting at
0xffffffc00005f000.
3387 DEF("L", HAS_ARG
, QEMU_OPTION_L
, \
3388 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
3393 Set the directory
for the BIOS
, VGA BIOS and keymaps
.
3395 To list all the data directories
, use @code
{-L help
}.
3398 DEF("bios", HAS_ARG
, QEMU_OPTION_bios
, \
3399 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL
)
3401 @item
-bios @
var{file
}
3403 Set the filename
for the BIOS
.
3406 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm
, \
3407 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL
)
3411 Enable KVM full virtualization support
. This option is only available
3412 if KVM support is enabled when compiling
.
3415 DEF("enable-hax", 0, QEMU_OPTION_enable_hax
, \
3416 "-enable-hax enable HAX virtualization support\n", QEMU_ARCH_I386
)
3420 Enable
HAX (Hardware
-based Acceleration eXecution
) support
. This option
3421 is only available
if HAX support is enabled when compiling
. HAX is only
3422 applicable to MAC and Windows platform
, and thus does not conflict with
3426 DEF("xen-domid", HAS_ARG
, QEMU_OPTION_xen_domid
,
3427 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL
)
3428 DEF("xen-create", 0, QEMU_OPTION_xen_create
,
3429 "-xen-create create domain using xen hypercalls, bypassing xend\n"
3430 " warning: should not be used when xend is in use\n",
3432 DEF("xen-attach", 0, QEMU_OPTION_xen_attach
,
3433 "-xen-attach attach to existing xen domain\n"
3434 " xend will use this when starting QEMU\n",
3436 DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict
,
3437 "-xen-domid-restrict restrict set of available xen operations\n"
3438 " to specified domain id. (Does not affect\n"
3439 " xenpv machine type).\n",
3442 @item
-xen
-domid @
var{id
}
3444 Specify xen guest domain @
var{id
} (XEN only
).
3447 Create domain
using xen hypercalls
, bypassing xend
.
3448 Warning
: should not be used when xend is
in use (XEN only
).
3451 Attach to existing xen domain
.
3452 xend will use
this when starting
QEMU (XEN only
).
3453 @findex
-xen
-domid
-restrict
3454 Restrict set of available xen operations to specified domain
id (XEN only
).
3457 DEF("no-reboot", 0, QEMU_OPTION_no_reboot
, \
3458 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL
)
3462 Exit instead of rebooting
.
3465 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown
, \
3466 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL
)
3469 @findex
-no
-shutdown
3470 Don
't exit QEMU on guest shutdown, but instead only stop the emulation.
3471 This allows for instance switching to monitor to commit changes to the
3475 DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
3476 "-loadvm [tag|id]\n" \
3477 " start right away with a saved state (loadvm in monitor)\n",
3480 @item -loadvm @var{file}
3482 Start right away with a saved state (@code{loadvm} in monitor)
3486 DEF("daemonize", 0, QEMU_OPTION_daemonize, \
3487 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
3492 Daemonize the QEMU process after initialization. QEMU will not detach from
3493 standard IO until it is ready to receive connections on any of its devices.
3494 This option is a useful way for external programs to launch QEMU without having
3495 to cope with initialization race conditions.
3498 DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
3499 "-option-rom rom load a file, rom, into the option ROM space\n",
3502 @item -option-rom @var{file}
3504 Load the contents of @var{file} as an option ROM.
3505 This option is useful to load things like EtherBoot.
3508 HXCOMM Silently ignored for compatibility
3509 DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL)
3511 HXCOMM Options deprecated by -rtc
3512 DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
3513 DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
3515 DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
3516 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
3517 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
3522 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
3524 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
3525 UTC or local time, respectively. @code{localtime} is required for correct date in
3526 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
3527 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
3529 By default the RTC is driven by the host system time. This allows using of the
3530 RTC as accurate reference clock inside the guest, specifically if the host
3531 time is smoothly following an accurate external reference clock, e.g. via NTP.
3532 If you want to isolate the guest time from the host, you can set @option{clock}
3533 to @code{rt} instead. To even prevent it from progressing during suspension,
3534 you can set it to @code{vm}.
3536 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
3537 specifically with Windows' ACPI HAL
. This option will
try to figure out how
3538 many timer interrupts were not processed by the Windows guest and will
3542 DEF("icount", HAS_ARG
, QEMU_OPTION_icount
, \
3543 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \
3544 " enable virtual instruction counter with 2^N clock ticks per\n" \
3545 " instruction, enable aligning the host and virtual clocks\n" \
3546 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL
)
3548 @item
-icount
[shift
=@
var{N
}|auto
][,rr
=record|replay
,rrfile
=@
var{filename
},rrsnapshot
=@
var{snapshot
}]
3550 Enable virtual instruction counter
. The virtual cpu will execute one
3551 instruction every
2^@
var{N
} ns of virtual time
. If @code
{auto
} is specified
3552 then the virtual cpu speed will be automatically adjusted to keep virtual
3553 time within a few seconds of real time
.
3555 When the virtual cpu is sleeping
, the virtual time will advance at
default
3556 speed unless @option
{sleep
=on|off
} is specified
.
3557 With @option
{sleep
=on|off
}, the virtual time will jump to the next timer deadline
3558 instantly whenever the virtual cpu goes to sleep mode and will not advance
3559 if no timer is enabled
. This behavior give deterministic execution times from
3560 the guest point of view
.
3562 Note that
while this option can give deterministic behavior
, it does not
3563 provide cycle accurate emulation
. Modern CPUs contain superscalar out of
3564 order cores with complex cache hierarchies
. The number of instructions
3565 executed often has little or no correlation with actual performance
.
3567 @option
{align
=on
} will activate the delay algorithm which will
try
3568 to synchronise the host clock and the virtual clock
. The goal is to
3569 have a guest running at the real frequency imposed by the shift option
.
3570 Whenever the guest clock is behind the host clock and
if
3571 @option
{align
=on
} is specified then we print a message to the user
3572 to inform about the delay
.
3573 Currently
this option does not work when @option
{shift
} is @code
{auto
}.
3574 Note
: The sync algorithm will work
for those shift values
for which
3575 the guest clock runs ahead of the host clock
. Typically
this happens
3576 when the shift value is
high (how high depends on the host machine
).
3578 When @option
{rr
} option is specified deterministic record
/replay is enabled
.
3579 Replay log is written into @
var{filename
} file
in record mode and
3580 read from
this file
in replay mode
.
3582 Option rrsnapshot is used to create
new vm snapshot named @
var{snapshot
}
3583 at the start of execution recording
. In replay mode
this option is used
3584 to load the initial VM state
.
3587 DEF("watchdog", HAS_ARG
, QEMU_OPTION_watchdog
, \
3588 "-watchdog model\n" \
3589 " enable virtual hardware watchdog [default=none]\n",
3592 @item
-watchdog @
var{model
}
3594 Create a virtual hardware watchdog device
. Once
enabled (by a guest
3595 action
), the watchdog must be periodically polled by an agent inside
3596 the guest or
else the guest will be restarted
. Choose a model
for
3597 which your guest has drivers
.
3599 The @
var{model
} is the model of hardware watchdog to emulate
. Use
3600 @code
{-watchdog help
} to list available hardware models
. Only one
3601 watchdog can be enabled
for a guest
.
3603 The following models may be available
:
3606 iBASE
700 is a very simple ISA watchdog with a single timer
.
3608 Intel
6300ESB I
/O controller hub is a much more featureful PCI
-based
3609 dual
-timer watchdog
.
3611 A virtual watchdog
for s390x backed by the diagnose
288 hypercall
3612 (currently KVM only
).
3616 DEF("watchdog-action", HAS_ARG
, QEMU_OPTION_watchdog_action
, \
3617 "-watchdog-action reset|shutdown|poweroff|inject-nmi|pause|debug|none\n" \
3618 " action when watchdog fires [default=reset]\n",
3621 @item
-watchdog
-action @
var{action
}
3622 @findex
-watchdog
-action
3624 The @
var{action
} controls what QEMU will
do when the watchdog timer
3627 @code
{reset
} (forcefully reset the guest
).
3628 Other possible actions are
:
3629 @code
{shutdown
} (attempt to gracefully shutdown the guest
),
3630 @code
{poweroff
} (forcefully poweroff the guest
),
3631 @code
{inject
-nmi
} (inject a NMI into the guest
),
3632 @code
{pause
} (pause the guest
),
3633 @code
{debug
} (print a debug message and
continue), or
3634 @code
{none
} (do nothing
).
3636 Note that the @code
{shutdown
} action requires that the guest responds
3637 to ACPI signals
, which it may not be able to
do in the sort of
3638 situations where the watchdog would have expired
, and thus
3639 @code
{-watchdog
-action shutdown
} is not recommended
for production use
.
3644 @item
-watchdog i6300esb
-watchdog
-action pause
3645 @itemx
-watchdog ib700
3649 DEF("echr", HAS_ARG
, QEMU_OPTION_echr
, \
3650 "-echr chr set terminal escape character instead of ctrl-a\n",
3654 @item
-echr @
var{numeric_ascii_value
}
3656 Change the escape character used
for switching to the monitor when
using
3657 monitor and serial sharing
. The
default is @code
{0x01} when
using the
3658 @code
{-nographic
} option
. @code
{0x01} is equal to pressing
3659 @code
{Control
-a
}. You can select a different character from the ascii
3660 control keys where
1 through
26 map to Control
-a through Control
-z
. For
3661 instance you could use the either of the following to change the escape
3662 character to Control
-t
.
3669 DEF("virtioconsole", HAS_ARG
, QEMU_OPTION_virtiocon
, \
3670 "-virtioconsole c\n" \
3671 " set virtio console\n", QEMU_ARCH_ALL
)
3673 @item
-virtioconsole @
var{c
}
3674 @findex
-virtioconsole
3677 This option is maintained
for backward compatibility
.
3679 Please use @code
{-device virtconsole
} for the
new way of invocation
.
3682 DEF("show-cursor", 0, QEMU_OPTION_show_cursor
, \
3683 "-show-cursor show cursor\n", QEMU_ARCH_ALL
)
3686 @findex
-show
-cursor
3690 DEF("tb-size", HAS_ARG
, QEMU_OPTION_tb_size
, \
3691 "-tb-size n set TB size\n", QEMU_ARCH_ALL
)
3693 @item
-tb
-size @
var{n
}
3698 DEF("incoming", HAS_ARG
, QEMU_OPTION_incoming
, \
3699 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \
3700 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \
3701 "-incoming unix:socketpath\n" \
3702 " prepare for incoming migration, listen on\n" \
3703 " specified protocol and socket address\n" \
3704 "-incoming fd:fd\n" \
3705 "-incoming exec:cmdline\n" \
3706 " accept incoming migration on given file descriptor\n" \
3707 " or from given external command\n" \
3708 "-incoming defer\n" \
3709 " wait for the URI to be specified via migrate_incoming\n",
3712 @item
-incoming tcp
:[@
var{host
}]:@
var{port
}[,to
=@
var{maxport
}][,ipv4
][,ipv6
]
3713 @itemx
-incoming rdma
:@
var{host
}:@
var{port
}[,ipv4
][,ipv6
]
3715 Prepare
for incoming migration
, listen on a given tcp port
.
3717 @item
-incoming unix
:@
var{socketpath
}
3718 Prepare
for incoming migration
, listen on a given unix socket
.
3720 @item
-incoming fd
:@
var{fd
}
3721 Accept incoming migration from a given filedescriptor
.
3723 @item
-incoming exec
:@
var{cmdline
}
3724 Accept incoming migration as an output from specified external command
.
3726 @item
-incoming defer
3727 Wait
for the URI to be specified via migrate_incoming
. The monitor can
3728 be used to change
settings (such as migration parameters
) prior to issuing
3729 the migrate_incoming to allow the migration to begin
.
3732 DEF("only-migratable", 0, QEMU_OPTION_only_migratable
, \
3733 "-only-migratable allow only migratable devices\n", QEMU_ARCH_ALL
)
3735 @item
-only
-migratable
3736 @findex
-only
-migratable
3737 Only allow migratable devices
. Devices will not be allowed to enter an
3741 DEF("nodefaults", 0, QEMU_OPTION_nodefaults
, \
3742 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL
)
3746 Don
't create default devices. Normally, QEMU sets the default devices like serial
3747 port, parallel port, virtual console, monitor device, VGA adapter, floppy and
3748 CD-ROM drive and others. The @code{-nodefaults} option will disable all those
3753 DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
3754 "-chroot dir chroot to dir just before starting the VM\n",
3758 @item -chroot @var{dir}
3760 Immediately before starting guest execution, chroot to the specified
3761 directory. Especially useful in combination with -runas.
3765 DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
3766 "-runas user change to user id user just before starting the VM\n",
3770 @item -runas @var{user}
3772 Immediately before starting guest execution, drop root privileges, switching
3773 to the specified user.
3776 DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
3777 "-prom-env variable=value\n"
3778 " set OpenBIOS nvram variables\n",
3779 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3781 @item -prom-env @var{variable}=@var{value}
3783 Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
3785 DEF("semihosting", 0, QEMU_OPTION_semihosting,
3786 "-semihosting semihosting mode\n",
3787 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3791 @findex -semihosting
3792 Enable semihosting mode (ARM, M68K, Xtensa, MIPS only).
3794 DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config,
3795 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \
3796 " semihosting configuration\n",
3797 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3800 @item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]
3801 @findex -semihosting-config
3802 Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only).
3804 @item target=@code{native|gdb|auto}
3805 Defines where the semihosting calls will be addressed, to QEMU (@code{native})
3806 or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb}
3807 during debug sessions and @code{native} otherwise.
3808 @item arg=@var{str1},arg=@var{str2},...
3809 Allows the user to pass input arguments, and can be used multiple times to build
3810 up a list. The old-style @code{-kernel}/@code{-append} method of passing a
3811 command line is still supported for backward compatibility. If both the
3812 @code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are
3813 specified, the former is passed to semihosting as it always takes precedence.
3816 DEF("old-param", 0, QEMU_OPTION_old_param,
3817 "-old-param old param mode\n", QEMU_ARCH_ARM)
3820 @findex -old-param (ARM)
3821 Old param mode (ARM only).
3824 DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
3825 "-sandbox on[,obsolete=allow|deny][,elevateprivileges=allow|deny|children]\n" \
3826 " [,spawn=allow|deny][,resourcecontrol=allow|deny]\n" \
3827 " Enable seccomp mode 2 system call filter (default 'off
').\n" \
3828 " use 'obsolete
' to allow obsolete system calls that are provided\n" \
3829 " by the kernel, but typically no longer used by modern\n" \
3830 " C library implementations.\n" \
3831 " use 'elevateprivileges
' to allow or deny QEMU process to elevate\n" \
3832 " its privileges by blacklisting all set*uid|gid system calls.\n" \
3833 " The value 'children
' will deny set*uid|gid system calls for\n" \
3834 " main QEMU process but will allow forks and execves to run unprivileged\n" \
3835 " use 'spawn
' to avoid QEMU to spawn new threads or processes by\n" \
3836 " blacklisting *fork and execve\n" \
3837 " use 'resourcecontrol
' to disable process affinity and schedular priority\n",
3840 @item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}]
3842 Enable Seccomp mode 2 system call filter. 'on
' will enable syscall filtering and 'off
' will
3843 disable it. The default is 'off
'.
3845 @item obsolete=@var{string}
3846 Enable Obsolete system calls
3847 @item elevateprivileges=@var{string}
3848 Disable set*uid|gid system calls
3849 @item spawn=@var{string}
3850 Disable *fork and execve
3851 @item resourcecontrol=@var{string}
3852 Disable process affinity and schedular priority
3856 DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
3857 "-readconfig <file>\n", QEMU_ARCH_ALL)
3859 @item -readconfig @var{file}
3861 Read device configuration from @var{file}. This approach is useful when you want to spawn
3862 QEMU process with many command line options but you don't want to exceed the command line
3865 DEF("writeconfig", HAS_ARG
, QEMU_OPTION_writeconfig
,
3866 "-writeconfig <file>\n"
3867 " read/write config file\n", QEMU_ARCH_ALL
)
3869 @item
-writeconfig @
var{file
}
3870 @findex
-writeconfig
3871 Write device configuration to @
var{file
}. The @
var{file
} can be either filename to save
3872 command line and device configuration into file or dash @code
{-}) character to print the
3873 output to stdout
. This can be later used as input file
for @code
{-readconfig
} option
.
3875 HXCOMM Deprecated
, same as
-no
-user
-config
3876 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig
, "", QEMU_ARCH_ALL
)
3877 DEF("no-user-config", 0, QEMU_OPTION_nouserconfig
,
3879 " do not load default user-provided config files at startup\n",
3882 @item
-no
-user
-config
3883 @findex
-no
-user
-config
3884 The @code
{-no
-user
-config
} option makes QEMU not load any of the user
-provided
3885 config files on @
var{sysconfdir
}.
3887 DEF("trace", HAS_ARG
, QEMU_OPTION_trace
,
3888 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
3889 " specify tracing options\n",
3892 HXCOMM This line is not accurate
, as some sub
-options are backend
-specific but
3893 HXCOMM HX does not support conditional compilation of text
.
3894 @item
-trace [[enable
=]@
var{pattern
}][,events
=@
var{file
}][,file
=@
var{file
}]
3896 @include qemu
-option
-trace.texi
3900 DEF("qtest", HAS_ARG
, QEMU_OPTION_qtest
, "", QEMU_ARCH_ALL
)
3901 DEF("qtest-log", HAS_ARG
, QEMU_OPTION_qtest_log
, "", QEMU_ARCH_ALL
)
3904 DEF("enable-fips", 0, QEMU_OPTION_enablefips
,
3905 "-enable-fips enable FIPS 140-2 compliance\n",
3910 @findex
-enable
-fips
3911 Enable FIPS
140-2 compliance mode
.
3914 HXCOMM Deprecated by
-machine accel
=tcg property
3915 DEF("no-kvm", 0, QEMU_OPTION_no_kvm
, "", QEMU_ARCH_I386
)
3917 HXCOMM Deprecated by kvm
-pit driver properties
3918 DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection
,
3921 HXCOMM Deprecated by
-machine kernel_irqchip
=on|off property
3922 DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip
, "", QEMU_ARCH_I386
)
3924 HXCOMM
Deprecated (ignored
)
3925 DEF("tdf", 0, QEMU_OPTION_tdf
,"", QEMU_ARCH_ALL
)
3927 DEF("msg", HAS_ARG
, QEMU_OPTION_msg
,
3928 "-msg timestamp[=on|off]\n"
3929 " change the format of messages\n"
3930 " on|off controls leading timestamps (default:on)\n",
3933 @item
-msg timestamp
[=on|off
]
3935 prepend a timestamp to each log message
.(default:on
)
3938 DEF("dump-vmstate", HAS_ARG
, QEMU_OPTION_dump_vmstate
,
3939 "-dump-vmstate <file>\n"
3940 " Output vmstate information in JSON format to file.\n"
3941 " Use the scripts/vmstate-static-checker.py file to\n"
3942 " check for possible regressions in migration code\n"
3943 " by comparing two such vmstate dumps.\n",
3946 @item
-dump
-vmstate @
var{file
}
3947 @findex
-dump
-vmstate
3948 Dump json
-encoded vmstate information
for current machine type to file
3957 DEFHEADING(Generic object creation
:)
3962 DEF("object", HAS_ARG
, QEMU_OPTION_object
,
3963 "-object TYPENAME[,PROP1=VALUE1,...]\n"
3964 " create a new object of type TYPENAME setting properties\n"
3965 " in the order they are specified. Note that the 'id'\n"
3966 " property must be set. These objects are placed in the\n"
3967 " '/objects' path.\n",
3970 @item
-object @
var{typename
}[,@
var{prop1
}=@
var{value1
},...]
3972 Create a
new object of type @
var{typename
} setting properties
3973 in the order they are specified
. Note that the
'id'
3974 property must be set
. These objects are placed
in the
3979 @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
}
3981 Creates a memory file backend object
, which can be used to back
3982 the guest RAM with huge pages
.
3984 The @option
{id
} parameter is a unique ID that will be used to reference
this
3985 memory region when configuring the @option
{-numa
} argument
.
3987 The @option
{size
} option provides the size of the memory region
, and accepts
3988 common suffixes
, eg @option
{500M
}.
3990 The @option
{mem
-path
} provides the path to either a shared memory or huge page
3993 The @option
{share
} boolean option determines whether the memory
3994 region is marked as
private to QEMU
, or shared
. The latter allows
3995 a co
-operating external process to access the QEMU memory region
.
3997 The @option
{share
} is also required
for pvrdma devices due to
3998 limitations
in the RDMA API provided by Linux
.
4000 Setting share
=on might affect the ability to configure NUMA
4001 bindings
for the memory backend under some circumstances
, see
4002 Documentation
/vm
/numa_memory_policy
.txt on the Linux kernel
4003 source tree
for additional details
.
4005 Setting the @option
{discard
-data
} boolean option to @
var{on
}
4006 indicates that file contents can be destroyed when QEMU exits
,
4007 to avoid unnecessarily flushing data to the backing file
. Note
4008 that @option
{discard
-data
} is only an optimization
, and QEMU
4009 might not discard file contents
if it aborts unexpectedly or is
4010 terminated
using SIGKILL
.
4012 The @option
{merge
} boolean option enables memory merge
, also known as
4013 MADV_MERGEABLE
, so that Kernel Samepage Merging will consider the pages
for
4014 memory deduplication
.
4016 Setting the @option
{dump
} boolean option to @
var{off
} excludes the memory from
4017 core dumps
. This feature is also known as MADV_DONTDUMP
.
4019 The @option
{prealloc
} boolean option enables memory preallocation
.
4021 The @option
{host
-nodes
} option binds the memory range to a list of NUMA host
4024 The @option
{policy
} option sets the NUMA policy to one of the following values
:
4030 @item @
var{preferred
}
4031 prefer the given host node list
for allocation
4034 restrict memory allocation to the given host node list
4036 @item @
var{interleave
}
4037 interleave memory allocations across the given host node list
4040 The @option
{align
} option specifies the base address alignment when
4041 QEMU
mmap(2) @option
{mem
-path
}, and accepts common suffixes
, eg
4042 @option
{2M
}. Some backend store specified by @option
{mem
-path
}
4043 requires an alignment different than the
default one used by QEMU
, eg
4044 the device DAX
/dev
/dax0
.0 requires
2M alignment rather than
4K
. In
4045 such cases
, users can specify the required alignment via
this option
.
4047 @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
}
4049 Creates a memory backend object
, which can be used to back the guest RAM
.
4050 Memory backend objects offer more control than the @option
{-m
} option that is
4051 traditionally used to define guest RAM
. Please refer to
4052 @option
{memory
-backend
-file
} for a description of the options
.
4054 @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
}
4056 Creates an anonymous memory file backend object
, which allows QEMU to
4057 share the memory with an external
process (e
.g
. when
using
4058 vhost
-user
). The memory is allocated with memfd and optional
4059 sealing
. (Linux only
)
4061 The @option
{seal
} option creates a sealed
-file
, that will block
4062 further resizing the
memory ('on' by
default).
4064 The @option
{hugetlb
} option specify the file to be created resides
in
4065 the hugetlbfs
filesystem (since Linux
4.14). Used
in conjunction with
4066 the @option
{hugetlb
} option
, the @option
{hugetlbsize
} option specify
4067 the hugetlb page size on systems that support multiple hugetlb page
4068 sizes (it must be a power of
2 value supported by the system
).
4070 In some versions of Linux
, the @option
{hugetlb
} option is incompatible
4071 with the @option
{seal
} option (requires at least Linux
4.16).
4073 Please refer to @option
{memory
-backend
-file
} for a description of the
4076 @item
-object rng
-random
,id
=@
var{id
},filename
=@
var{/dev
/random
}
4078 Creates a random number generator backend which obtains entropy from
4079 a device on the host
. The @option
{id
} parameter is a unique ID that
4080 will be used to reference
this entropy backend from the @option
{virtio
-rng
}
4081 device
. The @option
{filename
} parameter specifies which file to obtain
4082 entropy from and
if omitted defaults to @option
{/dev
/random
}.
4084 @item
-object rng
-egd
,id
=@
var{id
},chardev
=@
var{chardevid
}
4086 Creates a random number generator backend which obtains entropy from
4087 an external daemon running on the host
. The @option
{id
} parameter is
4088 a unique ID that will be used to reference
this entropy backend from
4089 the @option
{virtio
-rng
} device
. The @option
{chardev
} parameter is
4090 the unique ID of a character device backend that provides the connection
4093 @item
-object tls
-creds
-anon
,id
=@
var{id
},endpoint
=@
var{endpoint
},dir
=@
var{/path
/to
/cred
/dir
},verify
-peer
=@
var{on|off
}
4095 Creates a TLS anonymous credentials object
, which can be used to provide
4096 TLS support on network backends
. The @option
{id
} parameter is a unique
4097 ID which network backends will use to access the credentials
. The
4098 @option
{endpoint
} is either @option
{server
} or @option
{client
} depending
4099 on whether the QEMU network backend that uses the credentials will be
4100 acting as a client or as a server
. If @option
{verify
-peer
} is enabled
4101 (the
default) then once the handshake is completed
, the peer credentials
4102 will be verified
, though
this is a no
-op
for anonymous credentials
.
4104 The @
var{dir
} parameter tells QEMU where to find the credential
4105 files
. For server endpoints
, this directory may contain a file
4106 @
var{dh
-params
.pem
} providing diffie
-hellman parameters to use
4107 for the TLS server
. If the file is missing
, QEMU will generate
4108 a set of DH parameters at startup
. This is a computationally
4109 expensive operation that consumes random pool entropy
, so it is
4110 recommended that a persistent set of parameters be generated
4113 @item
-object tls
-creds
-x509
,id
=@
var{id
},endpoint
=@
var{endpoint
},dir
=@
var{/path
/to
/cred
/dir
},verify
-peer
=@
var{on|off
},passwordid
=@
var{id
}
4115 Creates a TLS anonymous credentials object
, which can be used to provide
4116 TLS support on network backends
. The @option
{id
} parameter is a unique
4117 ID which network backends will use to access the credentials
. The
4118 @option
{endpoint
} is either @option
{server
} or @option
{client
} depending
4119 on whether the QEMU network backend that uses the credentials will be
4120 acting as a client or as a server
. If @option
{verify
-peer
} is enabled
4121 (the
default) then once the handshake is completed
, the peer credentials
4122 will be verified
. With x509 certificates
, this implies that the clients
4123 must be provided with valid client certificates too
.
4125 The @
var{dir
} parameter tells QEMU where to find the credential
4126 files
. For server endpoints
, this directory may contain a file
4127 @
var{dh
-params
.pem
} providing diffie
-hellman parameters to use
4128 for the TLS server
. If the file is missing
, QEMU will generate
4129 a set of DH parameters at startup
. This is a computationally
4130 expensive operation that consumes random pool entropy
, so it is
4131 recommended that a persistent set of parameters be generated
4134 For x509 certificate credentials the directory will contain further files
4135 providing the x509 certificates
. The certificates must be stored
4136 in PEM format
, in filenames @
var{ca
-cert
.pem
}, @
var{ca
-crl
.pem
} (optional
),
4137 @
var{server
-cert
.pem
} (only servers
), @
var{server
-key
.pem
} (only servers
),
4138 @
var{client
-cert
.pem
} (only clients
), and @
var{client
-key
.pem
} (only clients
).
4140 For the @
var{server
-key
.pem
} and @
var{client
-key
.pem
} files which
4141 contain sensitive
private keys
, it is possible to use an encrypted
4142 version by providing the @
var{passwordid
} parameter
. This provides
4143 the ID of a previously created @code
{secret
} object containing the
4144 password
for decryption
.
4146 @item
-object filter
-buffer
,id
=@
var{id
},netdev
=@
var{netdevid
},interval
=@
var{t
}[,queue
=@
var{all|rx|tx
}][,status
=@
var{on|off
}]
4148 Interval @
var{t
} can
't be 0, this filter batches the packet delivery: all
4149 packets arriving in a given interval on netdev @var{netdevid} are delayed
4150 until the end of the interval. Interval is in microseconds.
4151 @option{status} is optional that indicate whether the netfilter is
4152 on (enabled) or off (disabled), the default status for netfilter will be 'on
'.
4154 queue @var{all|rx|tx} is an option that can be applied to any netfilter.
4156 @option{all}: the filter is attached both to the receive and the transmit
4157 queue of the netdev (default).
4159 @option{rx}: the filter is attached to the receive queue of the netdev,
4160 where it will receive packets sent to the netdev.
4162 @option{tx}: the filter is attached to the transmit queue of the netdev,
4163 where it will receive packets sent by the netdev.
4165 @item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4167 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.
4169 @item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4171 filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev
4172 @
var{chardevid
},and redirect indev
's packet to filter.if it has the vnet_hdr_support flag,
4173 filter-redirector will redirect packet with vnet_hdr_len.
4174 Create a filter-redirector we need to differ outdev id from indev id, id can not
4175 be the same. we can just use indev or outdev, but at least one of indev or outdev
4176 need to be specified.
4178 @item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support]
4180 Filter-rewriter is a part of COLO project.It will rewrite tcp packet to
4181 secondary from primary to keep secondary tcp connection,and rewrite
4182 tcp packet to primary from secondary make tcp packet can be handled by
4183 client.if it has the vnet_hdr_support flag, we can parse packet with vnet header.
4187 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4188 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4189 -object filter-rewriter,id=rew0,netdev=hn0,queue=all
4191 @item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}]
4193 Dump the network traffic on netdev @var{dev} to the file specified by
4194 @var{filename}. At most @var{len} bytes (64k by default) per packet are stored.
4195 The file format is libpcap, so it can be analyzed with tools such as tcpdump
4198 @item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid}[,vnet_hdr_support]
4200 Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with
4201 secondary packet. If the packets are same, we will output primary
4202 packet to outdev@var{chardevid}, else we will notify colo-frame
4203 do checkpoint and send primary packet to outdev@var{chardevid}.
4204 if it has the vnet_hdr_support flag, colo compare will send/recv packet with vnet_hdr_len.
4206 we must use it with the help of filter-mirror and filter-redirector.
4211 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown
4212 -device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66
4213 -chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait
4214 -chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait
4215 -chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait
4216 -chardev socket,id=compare0-0,host=3.3.3.3,port=9001
4217 -chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait
4218 -chardev socket,id=compare_out0,host=3.3.3.3,port=9005
4219 -object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0
4220 -object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out
4221 -object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0
4222 -object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0
4225 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown
4226 -device e1000,netdev=hn0,mac=52:a4:00:12:78:66
4227 -chardev socket,id=red0,host=3.3.3.3,port=9003
4228 -chardev socket,id=red1,host=3.3.3.3,port=9004
4229 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4230 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4234 If you want to know the detail of above command line, you can read
4235 the colo-compare git log.
4237 @item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}]
4239 Creates a cryptodev backend which executes crypto opreation from
4240 the QEMU cipher APIS. The @var{id} parameter is
4241 a unique ID that will be used to reference this cryptodev backend from
4242 the @option{virtio-crypto} device. The @var{queues} parameter is optional,
4243 which specify the queue number of cryptodev backend, the default of
4248 # qemu-system-x86_64 \
4250 -object cryptodev-backend-builtin,id=cryptodev0 \
4251 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4255 @item -object cryptodev-vhost-user,id=@var{id},chardev=@var{chardevid}[,queues=@var{queues}]
4257 Creates a vhost-user cryptodev backend, backed by a chardev @var{chardevid}.
4258 The @var{id} parameter is a unique ID that will be used to reference this
4259 cryptodev backend from the @option{virtio-crypto} device.
4260 The chardev should be a unix domain socket backed one. The vhost-user uses
4261 a specifically defined protocol to pass vhost ioctl replacement messages
4262 to an application on the other end of the socket.
4263 The @var{queues} parameter is optional, which specify the queue number
4264 of cryptodev backend for multiqueue vhost-user, the default of @var{queues} is 1.
4268 # qemu-system-x86_64 \
4270 -chardev socket,id=chardev0,path=/path/to/socket \
4271 -object cryptodev-vhost-user,id=cryptodev0,chardev=chardev0 \
4272 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4276 @item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4277 @item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4279 Defines a secret to store a password, encryption key, or some other sensitive
4280 data. The sensitive data can either be passed directly via the @var{data}
4281 parameter, or indirectly via the @var{file} parameter. Using the @var{data}
4282 parameter is insecure unless the sensitive data is encrypted.
4284 The sensitive data can be provided in raw format (the default), or base64.
4285 When encoded as JSON, the raw format only supports valid UTF-8 characters,
4286 so base64 is recommended for sending binary data. QEMU will convert from
4287 which ever format is provided to the format it needs internally. eg, an
4288 RBD password can be provided in raw format, even though it will be base64
4289 encoded when passed onto the RBD sever.
4291 For added protection, it is possible to encrypt the data associated with
4292 a secret using the AES-256-CBC cipher. Use of encryption is indicated
4293 by providing the @var{keyid} and @var{iv} parameters. The @var{keyid}
4294 parameter provides the ID of a previously defined secret that contains
4295 the AES-256 decryption key. This key should be 32-bytes long and be
4296 base64 encoded. The @var{iv} parameter provides the random initialization
4297 vector used for encryption of this particular secret and should be a
4298 base64 encrypted string of the 16-byte IV.
4300 The simplest (insecure) usage is to provide the secret inline
4304 # $QEMU -object secret,id=sec0,data=letmein,format=raw
4308 The simplest secure usage is to provide the secret via a file
4310 # printf "letmein" > mypasswd.txt
4311 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw
4313 For greater security, AES-256-CBC should be used. To illustrate usage,
4314 consider the openssl command line tool which can encrypt the data. Note
4315 that when encrypting, the plaintext must be padded to the cipher block
4316 size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm.
4318 First a master key needs to be created in base64 encoding:
4321 # openssl rand -base64 32 > key.b64
4322 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"')
4325 Each secret to be encrypted needs to have a random initialization vector
4326 generated. These do not need to be kept secret
4329 # openssl rand -base64 16 > iv.b64
4330 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"')
4333 The secret to be defined can now be encrypted, in this case we're
4334 telling openssl to base64 encode the result
, but it could be left
4335 as raw bytes
if desired
.
4338 # SECRET
=$
(printf
"letmein" |
4339 openssl enc
-aes
-256-cbc
-a
-K $KEY
-iv $IV
)
4342 When launching QEMU
, create a master secret pointing to @code
{key
.b64
}
4343 and specify that to be used to decrypt the user password
. Pass the
4344 contents of @code
{iv
.b64
} to the second secret
4348 -object secret
,id
=secmaster0
,format
=base64
,file
=key
.b64 \
4349 -object secret
,id
=sec0
,keyid
=secmaster0
,format
=base64
,\
4350 data
=$SECRET
,iv
=$
(<iv
.b64
)
4358 HXCOMM This is the last statement
. Insert
new options before
this line
!