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 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 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
52 available machines
. Supported machine properties are
:
54 @item accel
=@
var{accels1
}[:@
var{accels2
}[:...]]
55 This is used to enable an accelerator
. Depending on the target architecture
,
56 kvm
, xen
, hax or tcg can be available
. By
default, tcg is used
. If there is
57 more than one accelerator specified
, the next one is used
if the previous one
59 @item kernel_irqchip
=on|off
60 Controls
in-kernel irqchip support
for the chosen accelerator when available
.
61 @item gfx_passthru
=on|off
62 Enables IGD GFX passthrough support
for the chosen machine when available
.
63 @item vmport
=on|off|auto
64 Enables emulation of VMWare IO port
, for vmmouse etc
. auto says to select the
65 value based on accel
. For accel
=xen the
default is off otherwise the
default
67 @item kvm_shadow_mem
=size
68 Defines the size of the KVM shadow MMU
.
69 @item dump
-guest
-core
=on|off
70 Include guest memory
in a core dump
. The
default is on
.
71 @item mem
-merge
=on|off
72 Enables or disables memory merge support
. This feature
, when supported by
73 the host
, de
-duplicates identical memory pages among VMs instances
75 @item aes
-key
-wrap
=on|off
76 Enables or disables AES key wrapping support on s390
-ccw hosts
. This feature
77 controls whether AES wrapping keys will be created to allow
78 execution of AES cryptographic functions
. The
default is on
.
79 @item dea
-key
-wrap
=on|off
80 Enables or disables DEA key wrapping support on s390
-ccw hosts
. This feature
81 controls whether DEA wrapping keys will be created to allow
82 execution of DEA cryptographic functions
. The
default is on
.
84 Enables or disables NVDIMM support
. The
default is off
.
85 @item s390
-squash
-mcss
=on|off
86 Enables or disables squashing subchannels into the
default css
.
91 HXCOMM Deprecated by
-machine
92 DEF("M", HAS_ARG
, QEMU_OPTION_M
, "", QEMU_ARCH_ALL
)
94 DEF("cpu", HAS_ARG
, QEMU_OPTION_cpu
,
95 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL
)
97 @item
-cpu @
var{model
}
99 Select CPU
model (@code
{-cpu help
} for list and additional feature selection
)
102 DEF("accel", HAS_ARG
, QEMU_OPTION_accel
,
103 "-accel [accel=]accelerator[,thread=single|multi]\n"
104 " select accelerator (kvm, xen, hax or tcg; use 'help' for a list)\n"
105 " thread=single|multi (enable multi-threaded TCG)", QEMU_ARCH_ALL
)
107 @item
-accel @
var{name
}[,prop
=@
var{value
}[,...]]
109 This is used to enable an accelerator
. Depending on the target architecture
,
110 kvm
, xen
, hax or tcg can be available
. By
default, tcg is used
. If there is
111 more than one accelerator specified
, the next one is used
if the previous one
114 @item thread
=single|multi
115 Controls number of TCG threads
. When the TCG is multi
-threaded there will be one
116 thread per vCPU therefor taking advantage of additional host cores
. The
default
117 is to enable multi
-threading where both the back
-end and front
-ends support it and
118 no incompatible TCG features have been
enabled (e
.g
. icount
/replay
).
122 DEF("smp", HAS_ARG
, QEMU_OPTION_smp
,
123 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
124 " set the number of CPUs to 'n' [default=1]\n"
125 " maxcpus= maximum number of total cpus, including\n"
126 " offline CPUs for hotplug, etc\n"
127 " cores= number of CPU cores on one socket\n"
128 " threads= number of threads on one CPU core\n"
129 " sockets= number of discrete sockets in the system\n",
132 @item
-smp
[cpus
=]@
var{n
}[,cores
=@
var{cores
}][,threads
=@
var{threads
}][,sockets
=@
var{sockets
}][,maxcpus
=@
var{maxcpus
}]
134 Simulate an SMP system with @
var{n
} CPUs
. On the PC target
, up to
255
135 CPUs are supported
. On Sparc32 target
, Linux limits the number of usable CPUs
137 For the PC target
, the number of @
var{cores
} per socket
, the number
138 of @
var{threads
} per cores and the total number of @
var{sockets
} can be
139 specified
. Missing values will be computed
. If any on the three values is
140 given
, the total number of CPUs @
var{n
} can be omitted
. @
var{maxcpus
}
141 specifies the maximum number of hotpluggable CPUs
.
144 DEF("numa", HAS_ARG
, QEMU_OPTION_numa
,
145 "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
146 "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
147 "-numa dist,src=source,dst=destination,val=distance\n", QEMU_ARCH_ALL
)
149 @item
-numa node
[,mem
=@
var{size
}][,cpus
=@
var{firstcpu
}[-@
var{lastcpu
}]][,nodeid
=@
var{node
}]
150 @itemx
-numa node
[,memdev
=@
var{id
}][,cpus
=@
var{firstcpu
}[-@
var{lastcpu
}]][,nodeid
=@
var{node
}]
151 @itemx
-numa dist
,src
=@
var{source
},dst
=@
var{destination
},val
=@
var{distance
}
152 @itemx
-numa cpu
,node
-id
=@
var{node
}[,socket
-id
=@
var{x
}][,core
-id
=@
var{y
}][,thread
-id
=@
var{z
}]
154 Define a NUMA node and assign RAM and VCPUs to it
.
155 Set the NUMA distance from a source node to a destination node
.
157 Legacy VCPU assignment uses @samp
{cpus
} option where
158 @
var{firstcpu
} and @
var{lastcpu
} are CPU indexes
. Each
159 @samp
{cpus
} option represent a contiguous range of CPU indexes
160 (or a single VCPU
if @
var{lastcpu
} is omitted
). A non
-contiguous
161 set of VCPUs can be represented by providing multiple @samp
{cpus
}
162 options
. If @samp
{cpus
} is omitted on all nodes
, VCPUs are automatically
165 For example
, the following option assigns VCPUs
0, 1, 2 and
5 to
168 -numa node
,cpus
=0-2,cpus
=5
171 @samp
{cpu
} option is a
new alternative to @samp
{cpus
} option
172 which uses @samp
{socket
-id|core
-id|thread
-id
} properties to assign
173 CPU objects to a @
var{node
} using topology layout properties of CPU
.
174 The set of properties is machine specific
, and depends on used
175 machine type
/@samp
{smp
} options
. It could be queried with
176 @samp
{hotpluggable
-cpus
} monitor command
.
177 @samp
{node
-id
} property specifies @
var{node
} to which CPU object
178 will be assigned
, it
's required for @var{node} to be declared
179 with @samp{node} option before it's used with @samp
{cpu
} option
.
184 -smp
1,sockets
=2,maxcpus
=2 \
185 -numa node
,nodeid
=0 -numa node
,nodeid
=1 \
186 -numa cpu
,node
-id
=0,socket
-id
=0 -numa cpu
,node
-id
=1,socket
-id
=1
189 @samp
{mem
} assigns a given RAM amount to a node
. @samp
{memdev
}
190 assigns RAM from a given memory backend device to a node
. If
191 @samp
{mem
} and @samp
{memdev
} are omitted
in all nodes
, RAM is
192 split equally between them
.
194 @samp
{mem
} and @samp
{memdev
} are mutually exclusive
. Furthermore
,
195 if one node uses @samp
{memdev
}, all of them have to use it
.
197 @
var{source
} and @
var{destination
} are NUMA node IDs
.
198 @
var{distance
} is the NUMA distance from @
var{source
} to @
var{destination
}.
199 The distance from a node to itself is always
10. If any pair of nodes is
200 given a distance
, then all pairs must be given distances
. Although
, when
201 distances are only given
in one direction
for each pair of nodes
, then
202 the distances
in the opposite directions are assumed to be the same
. If
,
203 however
, an asymmetrical pair of distances is given
for even one node
204 pair
, then all node pairs must be provided distance values
for both
205 directions
, even when they are symmetrical
. When a node is unreachable
206 from another node
, set the pair
's distance to 255.
208 Note that the -@option{numa} option doesn't allocate any of the
209 specified resources
, it just assigns existing resources to NUMA
210 nodes
. This means that one still has to use the @option
{-m
},
211 @option
{-smp
} options to allocate RAM and VCPUs respectively
.
215 DEF("add-fd", HAS_ARG
, QEMU_OPTION_add_fd
,
216 "-add-fd fd=fd,set=set[,opaque=opaque]\n"
217 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL
)
219 @item
-add
-fd fd
=@
var{fd
},set
=@
var{set
}[,opaque
=@
var{opaque
}]
222 Add a file descriptor to an fd set
. Valid options are
:
226 This option defines the file descriptor of which a duplicate is added to fd set
.
227 The file descriptor cannot be stdin
, stdout
, or stderr
.
229 This option defines the ID of the fd set to add the file descriptor to
.
230 @item opaque
=@
var{opaque
}
231 This option defines a free
-form string that can be used to describe @
var{fd
}.
234 You can open an image
using pre
-opened file descriptors from an fd set
:
237 -add
-fd fd
=3,set
=2,opaque
="rdwr:/path/to/file"
238 -add
-fd fd
=4,set
=2,opaque
="rdonly:/path/to/file"
239 -drive file
=/dev
/fdset
/2,index
=0,media
=disk
243 DEF("set", HAS_ARG
, QEMU_OPTION_set
,
244 "-set group.id.arg=value\n"
245 " set <arg> parameter for item <id> of type <group>\n"
246 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL
)
248 @item
-set @
var{group
}.@
var{id
}.@
var{arg
}=@
var{value
}
250 Set parameter @
var{arg
} for item @
var{id
} of type @
var{group
}
253 DEF("global", HAS_ARG
, QEMU_OPTION_global
,
254 "-global driver.property=value\n"
255 "-global driver=driver,property=property,value=value\n"
256 " set a global default for a driver property\n",
259 @item
-global @
var{driver
}.@
var{prop
}=@
var{value
}
260 @itemx
-global driver
=@
var{driver
},property
=@
var{property
},value
=@
var{value
}
262 Set
default value of @
var{driver
}'s property @var{prop} to @var{value}, e.g.:
265 qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk
268 In particular, you can use this to set driver properties for devices which are
269 created automatically by the machine model. To create a device which is not
270 created automatically and set properties on it, use -@option{device}.
272 -global @var{driver}.@var{prop}=@var{value} is shorthand for -global
273 driver=@var{driver},property=@var{prop},value=@var{value}. The
274 longhand syntax works even when @var{driver} contains a dot.
277 DEF("boot", HAS_ARG, QEMU_OPTION_boot,
278 "-boot [order=drives][,once=drives][,menu=on|off]\n"
279 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
280 " 'drives
': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
281 " 'sp_name
': the file's name that would be passed to bios as logo picture
, if menu
=on
\n"
282 " 'sp_time': the period that splash picture last
if menu
=on
, unit is ms
\n"
283 " 'rb_timeout': the timeout before guest reboot when boot failed
, unit is ms
\n",
286 @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]
288 Specify boot order @var{drives} as a string of drive letters. Valid
289 drive letters depend on the target architecture. The x86 PC uses: a, b
290 (floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
291 from network adapter 1-4), hard disk boot is the default. To apply a
292 particular boot order only on the first startup, specify it via
293 @option{once}. Note that the @option{order} or @option{once} parameter
294 should not be used together with the @option{bootindex} property of
295 devices, since the firmware implementations normally do not support both
298 Interactive boot menus/prompts can be enabled via @option{menu=on} as far
299 as firmware/BIOS supports them. The default is non-interactive boot.
301 A splash picture could be passed to bios, enabling user to show it as logo,
302 when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
303 supports them. Currently Seabios for X86 system support it.
304 limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
305 format(true color). The resolution should be supported by the SVGA mode, so
306 the recommended is 320x240, 640x480, 800x640.
308 A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms
309 when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not
310 reboot, qemu passes '-1' to bios by default. Currently Seabios for X86
313 Do strict boot via @option{strict=on} as far as firmware/BIOS
314 supports it. This only effects when boot priority is changed by
315 bootindex options. The default is non-strict boot.
318 # try to boot from network first, then from hard disk
319 qemu-system-i386 -boot order=nc
320 # boot from CD-ROM first, switch back to default order after reboot
321 qemu-system-i386 -boot once=d
322 # boot with a splash picture for 5 seconds.
323 qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
326 Note: The legacy format '-boot @var{drives}' is still supported but its
327 use is discouraged as it may be removed from future versions.
330 DEF("m
", HAS_ARG, QEMU_OPTION_m,
331 "-m
[size
=]megs
[,slots
=n
,maxmem
=size
]\n"
332 " configure guest RAM
\n"
333 " size
: initial amount of guest memory
\n"
334 " slots
: number of hotplug
slots (default: none
)\n"
335 " maxmem
: maximum amount of guest
memory (default: none
)\n"
336 "NOTE
: Some architectures might enforce a specific granularity
\n",
339 @item -m [size=]@var{megs}[,slots=n,maxmem=size]
341 Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB.
342 Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in
343 megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem}
344 could be used to set amount of hotpluggable memory slots and maximum amount of
345 memory. Note that @var{maxmem} must be aligned to the page size.
347 For example, the following command-line sets the guest startup RAM size to
348 1GB, creates 3 slots to hotplug additional memory and sets the maximum
349 memory the guest can reach to 4GB:
352 qemu-system-x86_64 -m 1G,slots=3,maxmem=4G
355 If @var{slots} and @var{maxmem} are not specified, memory hotplug won't
356 be enabled and the guest startup RAM will never increase.
359 DEF("mem
-path
", HAS_ARG, QEMU_OPTION_mempath,
360 "-mem
-path FILE provide backing storage
for guest RAM
\n", QEMU_ARCH_ALL)
362 @item -mem-path @var{path}
364 Allocate guest RAM from a temporarily created file in @var{path}.
367 DEF("mem
-prealloc
", 0, QEMU_OPTION_mem_prealloc,
368 "-mem
-prealloc preallocate guest
memory (use with
-mem
-path
)\n",
372 @findex -mem-prealloc
373 Preallocate memory when using -mem-path.
376 DEF("k
", HAS_ARG, QEMU_OPTION_k,
377 "-k language use keyboard
layout (for example
'fr' for French
)\n",
380 @item -k @var{language}
382 Use keyboard layout @var{language} (for example @code{fr} for
383 French). This option is only needed where it is not easy to get raw PC
384 keycodes (e.g. on Macs, with some X11 servers or with a VNC or curses
385 display). You don't normally need to use it on PC/Linux or PC/Windows
388 The available layouts are:
390 ar de-ch es fo fr-ca hu ja mk no pt-br sv
391 da en-gb et fr fr-ch is lt nl pl ru th
392 de en-us fi fr-be hr it lv nl-be pt sl tr
395 The default is @code{en-us}.
399 DEF("audio
-help
", 0, QEMU_OPTION_audio_help,
400 "-audio
-help print list of audio drivers and their options
\n",
405 Will show the audio subsystem help: list of drivers, tunable
409 DEF("soundhw
", HAS_ARG, QEMU_OPTION_soundhw,
410 "-soundhw c1
,... enable audio support
\n"
411 " and only specified sound
cards (comma separated list
)\n"
412 " use
'-soundhw help' to get the list of supported cards
\n"
413 " use
'-soundhw all' to enable all of them
\n", QEMU_ARCH_ALL)
415 @item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
417 Enable audio and selected sound hardware. Use 'help' to print all
418 available sound hardware.
421 qemu-system-i386 -soundhw sb16,adlib disk.img
422 qemu-system-i386 -soundhw es1370 disk.img
423 qemu-system-i386 -soundhw ac97 disk.img
424 qemu-system-i386 -soundhw hda disk.img
425 qemu-system-i386 -soundhw all disk.img
426 qemu-system-i386 -soundhw help
429 Note that Linux's i810_audio OSS kernel (for AC97) module might
430 require manually specifying clocking.
433 modprobe i810_audio clocking=48000
437 DEF("balloon
", HAS_ARG, QEMU_OPTION_balloon,
438 "-balloon none disable balloon device
\n"
439 "-balloon virtio
[,addr
=str
]\n"
440 " enable virtio balloon
device (default)\n", QEMU_ARCH_ALL)
444 Disable balloon device.
445 @item -balloon virtio[,addr=@var{addr}]
446 Enable virtio balloon device (default), optionally with PCI address
450 DEF("device
", HAS_ARG, QEMU_OPTION_device,
451 "-device driver
[,prop
[=value
][,...]]\n"
452 " add
device (based on driver
)\n"
453 " prop
=value
,... sets driver properties
\n"
454 " use
'-device help' to print all possible drivers
\n"
455 " use
'-device driver,help' to print all possible properties
\n",
458 @item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
460 Add device @var{driver}. @var{prop}=@var{value} sets driver
461 properties. Valid properties depend on the driver. To get help on
462 possible drivers and properties, use @code{-device help} and
463 @code{-device @var{driver},help}.
466 @item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}][,sdrfile=@var{file}][,furareasize=@var{val}][,furdatafile=@var{file}]
468 Add an IPMI BMC. This is a simulation of a hardware management
469 interface processor that normally sits on a system. It provides
470 a watchdog and the ability to reset and power control the system.
471 You need to connect this to an IPMI interface to make it useful
473 The IPMI slave address to use for the BMC. The default is 0x20.
474 This address is the BMC's address on the I2C network of management
475 controllers. If you don't know what this means, it is safe to ignore
480 The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
481 @item slave_addr=@var{val}
482 Define slave address to use for the BMC. The default is 0x20.
483 @item sdrfile=@var{file}
484 file containing raw Sensor Data Records (SDR) data. The default is none.
485 @item fruareasize=@var{val}
486 size of a Field Replaceable Unit (FRU) area. The default is 1024.
487 @item frudatafile=@var{file}
488 file containing raw Field Replaceable Unit (FRU) inventory data. The default is none.
491 @item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}]
493 Add a connection to an external IPMI BMC simulator. Instead of
494 locally emulating the BMC like the above item, instead connect
495 to an external entity that provides the IPMI services.
497 A connection is made to an external BMC simulator. If you do this, it
498 is strongly recommended that you use the "reconnect
=" chardev option
499 to reconnect to the simulator if the connection is lost. Note that if
500 this is not used carefully, it can be a security issue, as the
501 interface has the ability to send resets, NMIs, and power off the VM.
502 It's best if QEMU makes a connection to an external simulator running
503 on a secure port on localhost, so neither the simulator nor QEMU is
504 exposed to any outside network.
506 See the "lanserv
/README
.vm
" file in the OpenIPMI library for more
507 details on the external interface.
509 @item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
511 Add a KCS IPMI interafce on the ISA bus. This also adds a
512 corresponding ACPI and SMBIOS entries, if appropriate.
516 The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
517 @item ioport=@var{val}
518 Define the I/O address of the interface. The default is 0xca0 for KCS.
520 Define the interrupt to use. The default is 5. To disable interrupts,
524 @item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
526 Like the KCS interface, but defines a BT interface. The default port is
527 0xe4 and the default interrupt is 5.
531 DEF("name
", HAS_ARG, QEMU_OPTION_name,
532 "-name string1
[,process
=string2
][,debug
-threads
=on|off
]\n"
533 " set the name of the guest
\n"
534 " string1 sets the window title and string2 the process
name (on Linux
)\n"
535 " When debug
-threads is enabled
, individual threads are given a separate
name (on Linux
)\n"
536 " NOTE
: The thread names are
for debugging and not a stable API
.\n",
539 @item -name @var{name}
541 Sets the @var{name} of the guest.
542 This name will be displayed in the SDL window caption.
543 The @var{name} will also be used for the VNC server.
544 Also optionally set the top visible process name in Linux.
545 Naming of individual threads can also be enabled on Linux to aid debugging.
548 DEF("uuid
", HAS_ARG, QEMU_OPTION_uuid,
549 "-uuid
%08x
-%04x
-%04x
-%04x
-%012x
\n"
550 " specify machine UUID
\n", QEMU_ARCH_ALL)
552 @item -uuid @var{uuid}
562 DEFHEADING(Block device options)
567 DEF("fda
", HAS_ARG, QEMU_OPTION_fda,
568 "-fda
/-fdb file use
'file' as floppy disk
0/1 image
\n", QEMU_ARCH_ALL)
569 DEF("fdb
", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
571 @item -fda @var{file}
572 @itemx -fdb @var{file}
575 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}).
578 DEF("hda
", HAS_ARG, QEMU_OPTION_hda,
579 "-hda
/-hdb file use
'file' as IDE hard disk
0/1 image
\n", QEMU_ARCH_ALL)
580 DEF("hdb
", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
581 DEF("hdc
", HAS_ARG, QEMU_OPTION_hdc,
582 "-hdc
/-hdd file use
'file' as IDE hard disk
2/3 image
\n", QEMU_ARCH_ALL)
583 DEF("hdd
", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
585 @item -hda @var{file}
586 @itemx -hdb @var{file}
587 @itemx -hdc @var{file}
588 @itemx -hdd @var{file}
593 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
596 DEF("cdrom
", HAS_ARG, QEMU_OPTION_cdrom,
597 "-cdrom file use
'file' as IDE cdrom
image (cdrom is ide1 master
)\n",
600 @item -cdrom @var{file}
602 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
603 @option{-cdrom} at the same time). You can use the host CD-ROM by
604 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
607 DEF("blockdev
", HAS_ARG, QEMU_OPTION_blockdev,
608 "-blockdev
[driver
=]driver
[,node
-name
=N
][,discard
=ignore|unmap
]\n"
609 " [,cache
.direct
=on|off
][,cache
.no
-flush
=on|off
]\n"
610 " [,read
-only
=on|off
][,detect
-zeroes
=on|off|unmap
]\n"
611 " [,driver specific parameters
...]\n"
612 " configure a block backend
\n", QEMU_ARCH_ALL)
614 DEF("drive
", HAS_ARG, QEMU_OPTION_drive,
615 "-drive
[file
=file
][,if=type
][,bus
=n
][,unit
=m
][,media
=d
][,index
=i
]\n"
616 " [,cyls
=c
,heads
=h
,secs
=s
[,trans
=t
]][,snapshot
=on|off
]\n"
617 " [,cache
=writethrough|writeback|none|directsync|unsafe
][,format
=f
]\n"
618 " [,serial
=s
][,addr
=A
][,rerror
=ignore|stop|report
]\n"
619 " [,werror
=ignore|stop|report|enospc
][,id
=name
][,aio
=threads|native
]\n"
620 " [,readonly
=on|off
][,copy
-on
-read
=on|off
]\n"
621 " [,discard
=ignore|unmap
][,detect
-zeroes
=on|off|unmap
]\n"
622 " [[,bps
=b
]|
[[,bps_rd
=r
][,bps_wr
=w
]]]\n"
623 " [[,iops
=i
]|
[[,iops_rd
=r
][,iops_wr
=w
]]]\n"
624 " [[,bps_max
=bm
]|
[[,bps_rd_max
=rm
][,bps_wr_max
=wm
]]]\n"
625 " [[,iops_max
=im
]|
[[,iops_rd_max
=irm
][,iops_wr_max
=iwm
]]]\n"
626 " [[,iops_size
=is
]]\n"
628 " use
'file' as a drive image
\n", QEMU_ARCH_ALL)
630 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
633 Define a new drive. Valid options are:
636 @item file=@var{file}
637 This option defines which disk image (@pxref{disk_images}) to use with
638 this drive. If the filename contains comma, you must double it
639 (for instance, "file
=my
,,file
" to use file "my
,file
").
641 Special files such as iSCSI devices can be specified using protocol
642 specific URLs. See the section for "Device URL Syntax
" for more information.
643 @item if=@var{interface}
644 This option defines on which type on interface the drive is connected.
645 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio, none.
646 @item bus=@var{bus},unit=@var{unit}
647 These options define where is connected the drive by defining the bus number and
649 @item index=@var{index}
650 This option defines where is connected the drive by using an index in the list
651 of available connectors of a given interface type.
652 @item media=@var{media}
653 This option defines the type of the media: disk or cdrom.
654 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
655 These options have the same definition as they have in @option{-hdachs}.
656 @item snapshot=@var{snapshot}
657 @var{snapshot} is "on
" or "off
" and controls snapshot mode for the given drive
658 (see @option{-snapshot}).
659 @item cache=@var{cache}
660 @var{cache} is "none
", "writeback
", "unsafe
", "directsync
" or "writethrough
" and controls how the host cache is used to access block data.
662 @var{aio} is "threads
", or "native
" and selects between pthread based disk I/O and native Linux AIO.
663 @item discard=@var{discard}
664 @var{discard} is one of "ignore
" (or "off
") or "unmap
" (or "on
") and controls whether @dfn{discard} (also known as @dfn{trim} or @dfn{unmap}) requests are ignored or passed to the filesystem. Some machine types may not support discard requests.
665 @item format=@var{format}
666 Specify which disk @var{format} will be used rather than detecting
667 the format. Can be used to specify format=raw to avoid interpreting
668 an untrusted format header.
669 @item serial=@var{serial}
670 This option specifies the serial number to assign to the device.
671 @item addr=@var{addr}
672 Specify the controller's PCI address (if=virtio only).
673 @item werror=@var{action},rerror=@var{action}
674 Specify which @var{action} to take on write and read errors. Valid actions are:
675 "ignore
" (ignore the error and try to continue), "stop
" (pause QEMU),
676 "report
" (report the error to the guest), "enospc
" (pause QEMU only if the
677 host disk is full; report the error to the guest otherwise).
678 The default setting is @option{werror=enospc} and @option{rerror=report}.
680 Open drive @option{file} as read-only. Guest write attempts will fail.
681 @item copy-on-read=@var{copy-on-read}
682 @var{copy-on-read} is "on
" or "off
" and enables whether to copy read backing
683 file sectors into the image file.
684 @item detect-zeroes=@var{detect-zeroes}
685 @var{detect-zeroes} is "off
", "on
" or "unmap
" and enables the automatic
686 conversion of plain zero writes by the OS to driver specific optimized
687 zero write commands. You may even choose "unmap
" if @var{discard} is set
688 to "unmap
" to allow a zero write to be converted to an UNMAP operation.
689 @item bps=@var{b},bps_rd=@var{r},bps_wr=@var{w}
690 Specify bandwidth throttling limits in bytes per second, either for all request
691 types or for reads or writes only. Small values can lead to timeouts or hangs
692 inside the guest. A safe minimum for disks is 2 MB/s.
693 @item bps_max=@var{bm},bps_rd_max=@var{rm},bps_wr_max=@var{wm}
694 Specify bursts in bytes per second, either for all request types or for reads
695 or writes only. Bursts allow the guest I/O to spike above the limit
697 @item iops=@var{i},iops_rd=@var{r},iops_wr=@var{w}
698 Specify request rate limits in requests per second, either for all request
699 types or for reads or writes only.
700 @item iops_max=@var{bm},iops_rd_max=@var{rm},iops_wr_max=@var{wm}
701 Specify bursts in requests per second, either for all request types or for reads
702 or writes only. Bursts allow the guest I/O to spike above the limit
704 @item iops_size=@var{is}
705 Let every @var{is} bytes of a request count as a new request for iops
706 throttling purposes. Use this option to prevent guests from circumventing iops
707 limits by sending fewer but larger requests.
709 Join a throttling quota group with given name @var{g}. All drives that are
710 members of the same group are accounted for together. Use this option to
711 prevent guests from circumventing throttling limits by using many small disks
712 instead of a single larger disk.
715 By default, the @option{cache=writeback} mode is used. It will report data
716 writes as completed as soon as the data is present in the host page cache.
717 This is safe as long as your guest OS makes sure to correctly flush disk caches
718 where needed. If your guest OS does not handle volatile disk write caches
719 correctly and your host crashes or loses power, then the guest may experience
722 For such guests, you should consider using @option{cache=writethrough}. This
723 means that the host page cache will be used to read and write data, but write
724 notification will be sent to the guest only after QEMU has made sure to flush
725 each write to the disk. Be aware that this has a major impact on performance.
727 The host page cache can be avoided entirely with @option{cache=none}. This will
728 attempt to do disk IO directly to the guest's memory. QEMU may still perform
729 an internal copy of the data. Note that this is considered a writeback mode and
730 the guest OS must handle the disk write cache correctly in order to avoid data
731 corruption on host crashes.
733 The host page cache can be avoided while only sending write notifications to
734 the guest when the data has been flushed to the disk using
735 @option{cache=directsync}.
737 In case you don't care about data integrity over host failures, use
738 @option{cache=unsafe}. This option tells QEMU that it never needs to write any
739 data to the disk but can instead keep things in cache. If anything goes wrong,
740 like your host losing power, the disk storage getting disconnected accidentally,
741 etc. your image will most probably be rendered unusable. When using
742 the @option{-snapshot} option, unsafe caching is always used.
744 Copy-on-read avoids accessing the same backing file sectors repeatedly and is
745 useful when the backing file is over a slow network. By default copy-on-read
748 Instead of @option{-cdrom} you can use:
750 qemu-system-i386 -drive file=file,index=2,media=cdrom
753 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
756 qemu-system-i386 -drive file=file,index=0,media=disk
757 qemu-system-i386 -drive file=file,index=1,media=disk
758 qemu-system-i386 -drive file=file,index=2,media=disk
759 qemu-system-i386 -drive file=file,index=3,media=disk
762 You can open an image using pre-opened file descriptors from an fd set:
765 -add-fd fd=3,set=2,opaque="rdwr
:/path
/to
/file
"
766 -add-fd fd=4,set=2,opaque="rdonly
:/path
/to
/file
"
767 -drive file=/dev/fdset/2,index=0,media=disk
770 You can connect a CDROM to the slave of ide0:
772 qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
775 If you don't specify the "file
=" argument, you define an empty drive:
777 qemu-system-i386 -drive if=ide,index=1,media=cdrom
780 Instead of @option{-fda}, @option{-fdb}, you can use:
782 qemu-system-i386 -drive file=file,index=0,if=floppy
783 qemu-system-i386 -drive file=file,index=1,if=floppy
786 By default, @var{interface} is "ide
" and @var{index} is automatically
789 qemu-system-i386 -drive file=a -drive file=b"
793 qemu
-system
-i386
-hda a
-hdb b
797 DEF("mtdblock", HAS_ARG
, QEMU_OPTION_mtdblock
,
798 "-mtdblock file use 'file' as on-board Flash memory image\n",
801 @item
-mtdblock @
var{file
}
803 Use @
var{file
} as on
-board Flash memory image
.
806 DEF("sd", HAS_ARG
, QEMU_OPTION_sd
,
807 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL
)
811 Use @
var{file
} as SecureDigital card image
.
814 DEF("pflash", HAS_ARG
, QEMU_OPTION_pflash
,
815 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL
)
817 @item
-pflash @
var{file
}
819 Use @
var{file
} as a parallel flash image
.
822 DEF("snapshot", 0, QEMU_OPTION_snapshot
,
823 "-snapshot write to temporary files instead of disk image files\n",
828 Write to temporary files instead of disk image files
. In
this case,
829 the raw disk image you use is not written back
. You can however force
830 the write back by pressing @key
{C
-a s
} (@pxref
{disk_images
}).
833 DEF("hdachs", HAS_ARG
, QEMU_OPTION_hdachs
, \
834 "-hdachs c,h,s[,t]\n" \
835 " force hard disk 0 physical geometry and the optional BIOS\n" \
836 " translation (t=none or lba) (usually QEMU can guess them)\n",
839 @item
-hdachs @
var{c
},@
var{h
},@
var{s
},[,@
var{t
}]
841 Force hard disk
0 physical
geometry (1 <= @
var{c
} <= 16383, 1 <=
842 @
var{h
} <= 16, 1 <= @
var{s
} <= 63) and optionally force the BIOS
843 translation
mode (@
var{t
}=none
, lba or auto
). Usually QEMU can guess
844 all those parameters
. This option is deprecated
, please use
845 @code
{-device ide
-hd
,cyls
=c
,heads
=h
,secs
=s
,...} instead
.
848 DEF("fsdev", HAS_ARG
, QEMU_OPTION_fsdev
,
849 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
850 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n"
851 " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n"
852 " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n"
853 " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n"
854 " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n"
855 " [[,throttling.iops-size=is]]\n",
860 @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
}]
862 Define a
new file system device
. Valid options are
:
865 This option specifies the fs driver backend to use
.
866 Currently
"local", "handle" and
"proxy" file system drivers are supported
.
868 Specifies identifier
for this device
869 @item path
=@
var{path
}
870 Specifies the export path
for the file system device
. Files under
871 this path will be available to the
9p client on the guest
.
872 @item security_model
=@
var{security_model
}
873 Specifies the security model to be used
for this export path
.
874 Supported security models are
"passthrough", "mapped-xattr", "mapped-file" and
"none".
875 In
"passthrough" security model
, files are stored
using the same
876 credentials as they are created on the guest
. This requires QEMU
877 to run as root
. In
"mapped-xattr" security model
, some of the file
878 attributes like uid
, gid
, mode bits and link target are stored as
879 file attributes
. For
"mapped-file" these attributes are stored
in the
880 hidden
.virtfs_metadata directory
. Directories exported by
this security model cannot
881 interact with other unix tools
. "none" security model is same as
882 passthrough except the sever won
't report failures if it fails to
883 set file attributes like ownership. Security model is mandatory
884 only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
885 security model as a parameter
.
886 @item writeout
=@
var{writeout
}
887 This is an optional argument
. The only supported value is
"immediate".
888 This means that host page cache will be used to read and write data but
889 write notification will be sent to the guest only when the data has been
890 reported as written by the storage subsystem
.
892 Enables exporting
9p share as a readonly mount
for guests
. By
default
893 read
-write access is given
.
894 @item socket
=@
var{socket
}
895 Enables proxy filesystem driver to use passed socket file
for communicating
896 with virtfs
-proxy
-helper
897 @item sock_fd
=@
var{sock_fd
}
898 Enables proxy filesystem driver to use passed socket descriptor
for
899 communicating with virtfs
-proxy
-helper
. Usually a helper like libvirt
900 will create socketpair and pass one of the fds as sock_fd
903 -fsdev option is used along with
-device driver
"virtio-9p-pci".
904 @item
-device virtio
-9p
-pci
,fsdev
=@
var{id
},mount_tag
=@
var{mount_tag
}
905 Options
for virtio
-9p
-pci driver are
:
908 Specifies the id value specified along with
-fsdev option
909 @item mount_tag
=@
var{mount_tag
}
910 Specifies the tag name to be used by the guest to mount
this export point
915 DEF("virtfs", HAS_ARG
, QEMU_OPTION_virtfs
,
916 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
917 " [,id=id][,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
922 @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
}]
925 The general form of a Virtual File system pass
-through options are
:
928 This option specifies the fs driver backend to use
.
929 Currently
"local", "handle" and
"proxy" file system drivers are supported
.
931 Specifies identifier
for this device
932 @item path
=@
var{path
}
933 Specifies the export path
for the file system device
. Files under
934 this path will be available to the
9p client on the guest
.
935 @item security_model
=@
var{security_model
}
936 Specifies the security model to be used
for this export path
.
937 Supported security models are
"passthrough", "mapped-xattr", "mapped-file" and
"none".
938 In
"passthrough" security model
, files are stored
using the same
939 credentials as they are created on the guest
. This requires QEMU
940 to run as root
. In
"mapped-xattr" security model
, some of the file
941 attributes like uid
, gid
, mode bits and link target are stored as
942 file attributes
. For
"mapped-file" these attributes are stored
in the
943 hidden
.virtfs_metadata directory
. Directories exported by
this security model cannot
944 interact with other unix tools
. "none" security model is same as
945 passthrough except the sever won
't report failures if it fails to
946 set file attributes like ownership. Security model is mandatory only
947 for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
948 model as a parameter
.
949 @item writeout
=@
var{writeout
}
950 This is an optional argument
. The only supported value is
"immediate".
951 This means that host page cache will be used to read and write data but
952 write notification will be sent to the guest only when the data has been
953 reported as written by the storage subsystem
.
955 Enables exporting
9p share as a readonly mount
for guests
. By
default
956 read
-write access is given
.
957 @item socket
=@
var{socket
}
958 Enables proxy filesystem driver to use passed socket file
for
959 communicating with virtfs
-proxy
-helper
. Usually a helper like libvirt
960 will create socketpair and pass one of the fds as sock_fd
962 Enables proxy filesystem driver to use passed
'sock_fd' as the socket
963 descriptor
for interfacing with virtfs
-proxy
-helper
967 DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth
,
968 "-virtfs_synth Create synthetic file system image\n",
972 @findex
-virtfs_synth
973 Create synthetic file system image
981 DEFHEADING(USB options
)
986 DEF("usb", 0, QEMU_OPTION_usb
,
987 "-usb enable the USB driver (will be the default soon)\n",
992 Enable the USB
driver (will be the
default soon
)
995 DEF("usbdevice", HAS_ARG
, QEMU_OPTION_usbdevice
,
996 "-usbdevice name add the host or guest USB device 'name'\n",
1000 @item
-usbdevice @
var{devname
}
1002 Add the USB device @
var{devname
}. @xref
{usb_devices
}.
1007 Virtual Mouse
. This will
override the PS
/2 mouse emulation when activated
.
1010 Pointer device that uses absolute
coordinates (like a touchscreen
). This
1011 means QEMU is able to report the mouse position without having to grab the
1012 mouse
. Also overrides the PS
/2 mouse emulation when activated
.
1014 @item disk
:[format
=@
var{format
}]:@
var{file
}
1015 Mass storage device based on file
. The optional @
var{format
} argument
1016 will be used rather than detecting the format
. Can be used to specify
1017 @code
{format
=raw
} to avoid interpreting an untrusted format header
.
1019 @item host
:@
var{bus
}.@
var{addr
}
1020 Pass through the host device identified by @
var{bus
}.@
var{addr
} (Linux only
).
1022 @item host
:@
var{vendor_id
}:@
var{product_id
}
1023 Pass through the host device identified by @
var{vendor_id
}:@
var{product_id
}
1026 @item serial
:[vendorid
=@
var{vendor_id
}][,productid
=@
var{product_id
}]:@
var{dev
}
1027 Serial converter to host character device @
var{dev
}, see @code
{-serial
} for the
1031 Braille device
. This will use BrlAPI to display the braille output on a real
1034 @item net
:@
var{options
}
1035 Network adapter that supports CDC ethernet and RNDIS protocols
.
1045 DEFHEADING(Display options
)
1050 DEF("display", HAS_ARG
, QEMU_OPTION_display
,
1051 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
1052 " [,window_close=on|off][,gl=on|off]\n"
1053 "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n"
1054 "-display vnc=<display>[,<optargs>]\n"
1057 " select display type\n"
1058 "The default display is equivalent to\n"
1059 #
if defined(CONFIG_GTK
)
1060 "\t\"-display gtk\"\n"
1061 #elif
defined(CONFIG_SDL
)
1062 "\t\"-display sdl\"\n"
1063 #elif
defined(CONFIG_COCOA
)
1064 "\t\"-display cocoa\"\n"
1065 #elif
defined(CONFIG_VNC
)
1066 "\t\"-vnc localhost:0,to=99,id=default\"\n"
1068 "\t\"-display none\"\n"
1072 @item
-display @
var{type
}
1074 Select type of display to use
. This option is a replacement
for the
1075 old style
-sdl
/-curses
/... options
. Valid values
for @
var{type
} are
1078 Display video output via
SDL (usually
in a separate graphics
1079 window
; see the SDL documentation
for other possibilities
).
1081 Display video output via curses
. For graphics device models which
1082 support a text mode
, QEMU can display
this output
using a
1083 curses
/ncurses
interface. Nothing is displayed when the graphics
1084 device is
in graphical mode or
if the graphics device does not support
1085 a text mode
. Generally only the VGA device models support text mode
.
1087 Do not display video output
. The guest will still see an emulated
1088 graphics card
, but its output will not be displayed to the QEMU
1089 user
. This option differs from the
-nographic option
in that it
1090 only affects what is done with video output
; -nographic also changes
1091 the destination of the serial and parallel port data
.
1093 Display video output
in a GTK window
. This
interface provides drop
-down
1094 menus and other UI elements to configure and control the VM during
1097 Start a VNC server on display
<arg
>
1101 DEF("nographic", 0, QEMU_OPTION_nographic
,
1102 "-nographic disable graphical output and redirect serial I/Os to console\n",
1107 Normally
, if QEMU is compiled with graphical window support
, it displays
1108 output such as guest graphics
, guest console
, and the QEMU monitor
in a
1109 window
. With
this option
, you can totally disable graphical output so
1110 that QEMU is a simple command line application
. The emulated serial port
1111 is redirected on the console and muxed with the
monitor (unless
1112 redirected elsewhere explicitly
). Therefore
, you can still use QEMU to
1113 debug a Linux kernel with a serial console
. Use @key
{C
-a h
} for help on
1114 switching between the console and monitor
.
1117 DEF("curses", 0, QEMU_OPTION_curses
,
1118 "-curses shorthand for -display curses\n",
1123 Normally
, if QEMU is compiled with graphical window support
, it displays
1124 output such as guest graphics
, guest console
, and the QEMU monitor
in a
1125 window
. With
this option
, QEMU can display the VGA output when
in text
1126 mode
using a curses
/ncurses
interface. Nothing is displayed
in graphical
1130 DEF("no-frame", 0, QEMU_OPTION_no_frame
,
1131 "-no-frame open SDL window without a frame and window decorations\n",
1136 Do not use decorations
for SDL windows and start them
using the whole
1137 available screen space
. This makes the
using QEMU
in a dedicated desktop
1138 workspace more convenient
.
1141 DEF("alt-grab", 0, QEMU_OPTION_alt_grab
,
1142 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
1147 Use Ctrl
-Alt
-Shift to grab
mouse (instead of Ctrl
-Alt
). Note that
this also
1148 affects the special
keys (for fullscreen
, monitor
-mode switching
, etc
).
1151 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab
,
1152 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
1157 Use Right
-Ctrl to grab
mouse (instead of Ctrl
-Alt
). Note that
this also
1158 affects the special
keys (for fullscreen
, monitor
-mode switching
, etc
).
1161 DEF("no-quit", 0, QEMU_OPTION_no_quit
,
1162 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL
)
1166 Disable SDL window close capability
.
1169 DEF("sdl", 0, QEMU_OPTION_sdl
,
1170 "-sdl shorthand for -display sdl\n", QEMU_ARCH_ALL
)
1177 DEF("spice", HAS_ARG
, QEMU_OPTION_spice
,
1178 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
1179 " [,x509-key-file=<file>][,x509-key-password=<file>]\n"
1180 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
1181 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n"
1182 " [,tls-ciphers=<list>]\n"
1183 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
1184 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
1185 " [,sasl][,password=<secret>][,disable-ticketing]\n"
1186 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
1187 " [,jpeg-wan-compression=[auto|never|always]]\n"
1188 " [,zlib-glz-wan-compression=[auto|never|always]]\n"
1189 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
1190 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
1191 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
1192 " [,gl=[on|off]][,rendernode=<file>]\n"
1194 " at least one of {port, tls-port} is mandatory\n",
1197 @item
-spice @
var{option
}[,@
var{option
}[,...]]
1199 Enable the spice remote desktop protocol
. Valid options are
1204 Set the TCP port spice is listening on
for plaintext channels
.
1207 Set the IP address spice is listening on
. Default is any address
.
1212 Force
using the specified IP version
.
1214 @item password
=<secret
>
1215 Set the password you need to authenticate
.
1218 Require that the client use SASL to authenticate with the spice
.
1219 The exact choice of authentication method used is controlled from the
1220 system
/ user
's SASL configuration file for the 'qemu
' service. This
1221 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1222 unprivileged user, an environment variable SASL_CONF_PATH can be used
1223 to make it search alternate locations for the service config.
1224 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1225 it is recommended that SASL always be combined with the 'tls
' and
1226 'x509
' settings to enable use of SSL and server certificates. This
1227 ensures a data encryption preventing compromise of authentication
1230 @item disable-ticketing
1231 Allow client connects without authentication.
1233 @item disable-copy-paste
1234 Disable copy paste between the client and the guest.
1236 @item disable-agent-file-xfer
1237 Disable spice-vdagent based file-xfer between the client and the guest.
1240 Set the TCP port spice is listening on for encrypted channels.
1242 @item x509-dir=<dir>
1243 Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1245 @item x509-key-file=<file>
1246 @itemx x509-key-password=<file>
1247 @itemx x509-cert-file=<file>
1248 @itemx x509-cacert-file=<file>
1249 @itemx x509-dh-key-file=<file>
1250 The x509 file names can also be configured individually.
1252 @item tls-ciphers=<list>
1253 Specify which ciphers to use.
1255 @item tls-channel=[main|display|cursor|inputs|record|playback]
1256 @itemx plaintext-channel=[main|display|cursor|inputs|record|playback]
1257 Force specific channel to be used with or without TLS encryption. The
1258 options can be specified multiple times to configure multiple
1259 channels. The special name "default" can be used to set the default
1260 mode. For channels which are not explicitly forced into one mode the
1261 spice client is allowed to pick tls/plaintext as he pleases.
1263 @item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1264 Configure image compression (lossless).
1265 Default is auto_glz.
1267 @item jpeg-wan-compression=[auto|never|always]
1268 @itemx zlib-glz-wan-compression=[auto|never|always]
1269 Configure wan image compression (lossy for slow links).
1272 @item streaming-video=[off|all|filter]
1273 Configure video stream detection. Default is off.
1275 @item agent-mouse=[on|off]
1276 Enable/disable passing mouse events via vdagent. Default is on.
1278 @item playback-compression=[on|off]
1279 Enable/disable audio stream compression (using celt 0.5.1). Default is on.
1281 @item seamless-migration=[on|off]
1282 Enable/disable spice seamless migration. Default is off.
1285 Enable/disable OpenGL context. Default is off.
1287 @item rendernode=<file>
1288 DRM render node for OpenGL rendering. If not specified, it will pick
1289 the first available. (Since 2.9)
1294 DEF("portrait", 0, QEMU_OPTION_portrait,
1295 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
1300 Rotate graphical output 90 deg left (only PXA LCD).
1303 DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1304 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
1307 @item -rotate @var{deg}
1309 Rotate graphical output some deg left (only PXA LCD).
1312 DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1313 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n"
1314 " select video card type\n", QEMU_ARCH_ALL)
1316 @item -vga @var{type}
1318 Select type of VGA card to emulate. Valid values for @var{type} are
1321 Cirrus Logic GD5446 Video card. All Windows versions starting from
1322 Windows 95 should recognize and use this graphic card. For optimal
1323 performances, use 16 bit color depth in the guest and the host OS.
1324 (This card was the default before QEMU 2.2)
1326 Standard VGA card with Bochs VBE extensions. If your guest OS
1327 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1328 to use high resolution modes (>= 1280x1024x16) then you should use
1329 this option. (This card is the default since QEMU 2.2)
1331 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1332 recent XFree86/XOrg server or Windows guest with a driver for this
1335 QXL paravirtual graphic card. It is VGA compatible (including VESA
1336 2.0 VBE support). Works best with qxl guest drivers installed though.
1337 Recommended choice when using the spice protocol.
1339 (sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1340 sun4m machines and offers both 8-bit and 24-bit colour depths at a
1341 fixed resolution of 1024x768.
1343 (sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1344 for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1345 resolutions aimed at people wishing to run older Solaris versions.
1353 DEF("full-screen", 0, QEMU_OPTION_full_screen,
1354 "-full-screen start in full screen\n", QEMU_ARCH_ALL)
1357 @findex -full-screen
1358 Start in full screen.
1361 DEF("g", 1, QEMU_OPTION_g ,
1362 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
1363 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1365 @item -g @var{width}x@var{height}[x@var{depth}]
1367 Set the initial graphical resolution and depth (PPC, SPARC only).
1370 DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1371 "-vnc <display> shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL)
1373 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1375 Normally, if QEMU is compiled with graphical window support, it displays
1376 output such as guest graphics, guest console, and the QEMU monitor in a
1377 window. With this option, you can have QEMU listen on VNC display
1378 @var{display} and redirect the VGA display over the VNC session. It is
1379 very useful to enable the usb tablet device when using this option
1380 (option @option{-usbdevice tablet}). When using the VNC display, you
1381 must use the @option{-k} parameter to set the keyboard layout if you are
1382 not using en-us. Valid syntax for the @var{display} is
1388 With this option, QEMU will try next available VNC @var{display}s, until the
1389 number @var{L}, if the origianlly defined "-vnc @var{display}" is not
1390 available, e.g. port 5900+@var{display} is already used by another
1391 application. By default, to=0.
1393 @item @var{host}:@var{d}
1395 TCP connections will only be allowed from @var{host} on display @var{d}.
1396 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1397 be omitted in which case the server will accept connections from any host.
1399 @item unix:@var{path}
1401 Connections will be allowed over UNIX domain sockets where @var{path} is the
1402 location of a unix socket to listen for connections on.
1406 VNC is initialized but not started. The monitor @code{change} command
1407 can be used to later start the VNC server.
1411 Following the @var{display} value there may be one or more @var{option} flags
1412 separated by commas. Valid options are
1418 Connect to a listening VNC client via a ``reverse'' connection. The
1419 client is specified by the @var{display}. For reverse network
1420 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1421 is a TCP port number, not a display number.
1425 Opens an additional TCP listening port dedicated to VNC Websocket connections.
1426 If a bare @var{websocket} option is given, the Websocket port is
1427 5700+@var{display}. An alternative port can be specified with the
1428 syntax @code{websocket}=@var{port}.
1430 If @var{host} is specified connections will only be allowed from this host.
1431 It is possible to control the websocket listen address independently, using
1432 the syntax @code{websocket}=@var{host}:@var{port}.
1434 If no TLS credentials are provided, the websocket connection runs in
1435 unencrypted mode. If TLS credentials are provided, the websocket connection
1436 requires encrypted client connections.
1440 Require that password based authentication is used for client connections.
1442 The password must be set separately using the @code{set_password} command in
1443 the @ref{pcsys_monitor}. The syntax to change your password is:
1444 @code{set_password <protocol> <password>} where <protocol> could be either
1447 If you would like to change <protocol> password expiration, you should use
1448 @code{expire_password <protocol> <expiration-time>} where expiration time could
1449 be one of the following options: now, never, +seconds or UNIX time of
1450 expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1451 to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1454 You can also use keywords "now" or "never" for the expiration time to
1455 allow <protocol> password to expire immediately or never expire.
1457 @item tls-creds=@var{ID}
1459 Provides the ID of a set of TLS credentials to use to secure the
1460 VNC server. They will apply to both the normal VNC server socket
1461 and the websocket socket (if enabled). Setting TLS credentials
1462 will cause the VNC server socket to enable the VeNCrypt auth
1463 mechanism. The credentials should have been previously created
1464 using the @option{-object tls-creds} argument.
1466 The @option{tls-creds} parameter obsoletes the @option{tls},
1467 @option{x509}, and @option{x509verify} options, and as such
1468 it is not permitted to set both new and old type options at
1473 Require that client use TLS when communicating with the VNC server. This
1474 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1475 attack. It is recommended that this option be combined with either the
1476 @option{x509} or @option{x509verify} options.
1478 This option is now deprecated in favor of using the @option{tls-creds}
1481 @item x509=@var{/path/to/certificate/dir}
1483 Valid if @option{tls} is specified. Require that x509 credentials are used
1484 for negotiating the TLS session. The server will send its x509 certificate
1485 to the client. It is recommended that a password be set on the VNC server
1486 to provide authentication of the client when this is used. The path following
1487 this option specifies where the x509 certificates are to be loaded from.
1488 See the @ref{vnc_security} section for details on generating certificates.
1490 This option is now deprecated in favour of using the @option{tls-creds}
1493 @item x509verify=@var{/path/to/certificate/dir}
1495 Valid if @option{tls} is specified. Require that x509 credentials are used
1496 for negotiating the TLS session. The server will send its x509 certificate
1497 to the client, and request that the client send its own x509 certificate.
1498 The server will validate the client's certificate against the CA certificate
,
1499 and reject clients when validation fails
. If the certificate authority is
1500 trusted
, this is a sufficient authentication mechanism
. You may still wish
1501 to set a password on the VNC server as a second authentication layer
. The
1502 path following
this option specifies where the x509 certificates are to
1503 be loaded from
. See the @ref
{vnc_security
} section
for details on generating
1506 This option is now deprecated
in favour of
using the @option
{tls
-creds
}
1511 Require that the client use SASL to authenticate with the VNC server
.
1512 The exact choice of authentication method used is controlled from the
1513 system
/ user
's SASL configuration file for the 'qemu
' service. This
1514 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1515 unprivileged user, an environment variable SASL_CONF_PATH can be used
1516 to make it search alternate locations for the service config.
1517 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1518 it is recommended that SASL always be combined with the 'tls
' and
1519 'x509
' settings to enable use of SSL and server certificates. This
1520 ensures a data encryption preventing compromise of authentication
1521 credentials. See the @ref{vnc_security} section for details on using
1522 SASL authentication.
1526 Turn on access control lists for checking of the x509 client certificate
1527 and SASL party. For x509 certs, the ACL check is made against the
1528 certificate's distinguished name
. This is something that looks like
1529 @code
{C
=GB
,O
=ACME
,L
=Boston
,CN
=bob
}. For SASL party
, the ACL check is
1530 made against the username
, which depending on the SASL plugin
, may
1531 include a realm component
, eg @code
{bob
} or @code
{bob@@EXAMPLE
.COM
}.
1532 When the @option
{acl
} flag is set
, the initial access list will be
1533 empty
, with a @code
{deny
} policy
. Thus no one will be allowed to
1534 use the VNC server until the ACLs have been loaded
. This can be
1535 achieved
using the @code
{acl
} monitor command
.
1539 Enable lossy compression
methods (gradient
, JPEG
, ...). If
this
1540 option is set
, VNC client may receive lossy framebuffer updates
1541 depending on its encoding settings
. Enabling
this option can save
1542 a lot of bandwidth at the expense of quality
.
1546 Disable adaptive encodings
. Adaptive encodings are enabled by
default.
1547 An adaptive encoding will
try to detect frequently updated screen regions
,
1548 and send updates
in these regions
using a lossy
encoding (like JPEG
).
1549 This can be really helpful to save bandwidth when playing videos
. Disabling
1550 adaptive encodings restores the original
static behavior of encodings
1553 @item share
=[allow
-exclusive|force
-shared|ignore
]
1555 Set display sharing policy
. 'allow-exclusive' allows clients to ask
1556 for exclusive access
. As suggested by the rfb spec
this is
1557 implemented by dropping other connections
. Connecting multiple
1558 clients
in parallel requires all clients asking
for a shared session
1559 (vncviewer
: -shared
switch). This is the
default. 'force-shared'
1560 disables exclusive client access
. Useful
for shared desktop sessions
,
1561 where you don
't want someone forgetting specify -shared disconnect
1562 everybody else. 'ignore
' completely ignores the shared flag and
1563 allows everybody connect unconditionally. Doesn't conform to the rfb
1564 spec but is traditional QEMU behavior
.
1568 Set keyboard delay
, for key down and key up events
, in milliseconds
.
1569 Default is
1. Keyboards are low
-bandwidth devices
, so
this slowdown
1570 can help the device and guest to keep up and not lose events
in case
1571 events are arriving
in bulk
. Possible causes
for the latter are flaky
1572 network connections
, or scripts
for automated testing
.
1580 ARCHHEADING(, QEMU_ARCH_I386
)
1582 ARCHHEADING(i386 target only
, QEMU_ARCH_I386
)
1587 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack
,
1588 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1593 Use it when installing Windows
2000 to avoid a disk full bug
. After
1594 Windows
2000 is installed
, you no longer need
this option (this option
1595 slows down the IDE transfers
).
1598 HXCOMM Deprecated by
-rtc
1599 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack
, "", QEMU_ARCH_I386
)
1601 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk
,
1602 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1605 @item
-no
-fd
-bootchk
1606 @findex
-no
-fd
-bootchk
1607 Disable boot signature checking
for floppy disks
in BIOS
. May
1608 be needed to boot from old floppy disks
.
1611 DEF("no-acpi", 0, QEMU_OPTION_no_acpi
,
1612 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM
)
1616 Disable
ACPI (Advanced Configuration and Power Interface
) support
. Use
1617 it
if your guest OS complains about ACPI
problems (PC target machine
1621 DEF("no-hpet", 0, QEMU_OPTION_no_hpet
,
1622 "-no-hpet disable HPET\n", QEMU_ARCH_I386
)
1626 Disable HPET support
.
1629 DEF("acpitable", HAS_ARG
, QEMU_OPTION_acpitable
,
1630 "-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"
1631 " ACPI table description\n", QEMU_ARCH_I386
)
1633 @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
}]...]
1635 Add ACPI table with specified header fields and context from specified files
.
1636 For file
=, take whole ACPI table from the specified files
, including all
1637 ACPI
headers (possible overridden by other options
).
1638 For data
=, only data
1639 portion of the table is used
, all header information is specified
in the
1641 If a SLIC table is supplied to QEMU
, then the SLIC
's oem_id and oem_table_id
1642 fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order
1643 to ensure the field matches required by the Microsoft SLIC spec and the ACPI
1647 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1648 "-smbios file=binary\n"
1649 " load SMBIOS entry from binary file\n"
1650 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1652 " specify SMBIOS type 0 fields\n"
1653 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1654 " [,uuid=uuid][,sku=str][,family=str]\n"
1655 " specify SMBIOS type 1 fields\n"
1656 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1657 " [,asset=str][,location=str]\n"
1658 " specify SMBIOS type 2 fields\n"
1659 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n"
1661 " specify SMBIOS type 3 fields\n"
1662 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n"
1663 " [,asset=str][,part=str]\n"
1664 " specify SMBIOS type 4 fields\n"
1665 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n"
1666 " [,asset=str][,part=str][,speed=%d]\n"
1667 " specify SMBIOS type 17 fields\n",
1668 QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1670 @item -smbios file=@var{binary}
1672 Load SMBIOS entry from binary file.
1674 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1675 Specify SMBIOS type 0 fields
1677 @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}]
1678 Specify SMBIOS type 1 fields
1680 @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}]
1681 Specify SMBIOS type 2 fields
1683 @item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}]
1684 Specify SMBIOS type 3 fields
1686 @item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}]
1687 Specify SMBIOS type 4 fields
1689 @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}]
1690 Specify SMBIOS type 17 fields
1698 DEFHEADING(Network options)
1703 HXCOMM Legacy slirp options (now moved to -net user):
1705 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1706 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1707 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1709 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1713 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1715 "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n"
1716 " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n"
1717 " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n"
1718 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,tftp=dir]\n"
1719 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1721 "[,smb=dir[,smbserver=addr]]\n"
1723 " configure a user mode network backend with ID 'str
',\n"
1724 " its DHCP server and optional services\n"
1727 "-netdev tap,id=str,ifname=name\n"
1728 " configure a host TAP network backend with ID 'str
'\n"
1730 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n"
1731 " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n"
1732 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n"
1734 " configure a host TAP network backend with ID 'str
'\n"
1735 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1736 " use network scripts 'file
' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1737 " to configure it and 'dfile
' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1738 " to deconfigure it\n"
1739 " use '[down
]script
=no
' to disable script execution\n"
1740 " use network helper 'helper
' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1742 " use 'fd
=h
' to connect to an already opened TAP interface\n"
1743 " use 'fds
=x
:y
:...:z
' to connect to already opened multiqueue capable TAP interfaces\n"
1744 " use 'sndbuf
=nbytes
' to limit the size of the send buffer (the\n"
1745 " default is disabled 'sndbuf
=0' to enable flow control set 'sndbuf
=1048576')\n"
1746 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1747 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1748 " use vhost=on to enable experimental in kernel accelerator\n"
1749 " (only has effect for virtio guests which use MSIX)\n"
1750 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1751 " use 'vhostfd
=h
' to connect to an already opened vhost net device\n"
1752 " use 'vhostfds
=x
:y
:...:z to connect to multiple already opened vhost net devices
\n"
1753 " use
'queues=n' to specify the number of queues to be created
for multiqueue TAP
\n"
1754 " use
'poll-us=n' to speciy the maximum number of microseconds that could be
\n"
1755 " spent on busy polling
for vhost net
\n"
1756 "-netdev bridge
,id
=str
[,br
=bridge
][,helper
=helper
]\n"
1757 " configure a host TAP network backend with ID
'str' that is
\n"
1758 " connected to a
bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1759 " using the program
'helper (default=" DEFAULT_BRIDGE_HELPER ")\n"
1762 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n"
1763 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n"
1764 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n"
1765 " [,rxcookie=rxcookie][,offset=offset]\n"
1766 " configure a network backend with ID 'str
' connected to\n"
1767 " an Ethernet over L2TPv3 pseudowire.\n"
1768 " Linux kernel 3.3+ as well as most routers can talk\n"
1769 " L2TPv3. This transport allows connecting a VM to a VM,\n"
1770 " VM to a router and even VM to Host. It is a nearly-universal\n"
1771 " standard (RFC3391). Note - this implementation uses static\n"
1772 " pre-configured tunnels (same as the Linux kernel).\n"
1773 " use 'src
=' to specify source address\n"
1774 " use 'dst
=' to specify destination address\n"
1775 " use 'udp
=on
' to specify udp encapsulation\n"
1776 " use 'srcport
=' to specify source udp port\n"
1777 " use 'dstport
=' to specify destination udp port\n"
1778 " use 'ipv6
=on
' to force v6\n"
1779 " L2TPv3 uses cookies to prevent misconfiguration as\n"
1780 " well as a weak security measure\n"
1781 " use 'rxcookie
=0x012345678' to specify a rxcookie\n"
1782 " use 'txcookie
=0x012345678' to specify a txcookie\n"
1783 " use 'cookie64
=on
' to set cookie size to 64 bit, otherwise 32\n"
1784 " use 'counter
=off
' to force a 'cut
-down
' L2TPv3 with no counter\n"
1785 " use 'pincounter
=on
' to work around broken counter handling in peer\n"
1786 " use 'offset
=X
' to add an extra offset between header and data\n"
1788 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n"
1789 " configure a network backend to connect to another network\n"
1790 " using a socket connection\n"
1791 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1792 " configure a network backend to connect to a multicast maddr and port\n"
1793 " use 'localaddr
=addr
' to specify the host address to send packets from\n"
1794 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
1795 " configure a network backend to connect to another network\n"
1796 " using an UDP tunnel\n"
1798 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1799 " configure a network backend to connect to port 'n
' of a vde switch\n"
1800 " running on host and listening for incoming connections on 'socketpath
'.\n"
1801 " Use group 'groupname
' and mode 'octalmode
' to change default\n"
1802 " ownership and permissions for communication port.\n"
1804 #ifdef CONFIG_NETMAP
1805 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n"
1806 " attach to the existing netmap-enabled network interface 'name
', or to a\n"
1807 " VALE port (created on the fly) called 'name
' ('nmname
' is name of the \n"
1808 " netmap device, defaults to '/dev
/netmap
')\n"
1810 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n"
1811 " configure a vhost-user network, backed by a chardev 'dev
'\n"
1812 "-netdev hubport,id=str,hubid=n\n"
1813 " configure a hub port on QEMU VLAN 'n
'\n", QEMU_ARCH_ALL)
1814 DEF("net", HAS_ARG, QEMU_OPTION_net,
1815 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
1816 " old way to create a new NIC and connect it to VLAN 'n
'\n"
1817 " (use the '-device devtype
,netdev
=str
' option if possible instead)\n"
1818 "-net dump[,vlan=n][,file=f][,len=n]\n"
1819 " dump traffic on vlan 'n
' to file 'f
' (max n bytes per packet)\n"
1820 "-net none use it alone to have zero network devices. If no -net option\n"
1821 " is provided, the default is '-net nic
-net user
'\n"
1831 #ifdef CONFIG_NETMAP
1834 "socket][,vlan=n][,option][,option][,...]\n"
1835 " old way to initialize a host network interface\n"
1836 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL)
1838 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1840 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1841 = 0 is the default). The NIC is an e1000 by default on the PC
1842 target. Optionally, the MAC address can be changed to @var{mac}, the
1843 device address set to @var{addr} (PCI cards only),
1844 and a @var{name} can be assigned for use in monitor commands.
1845 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1846 that the card should have; this option currently only affects virtio cards; set
1847 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1848 NIC is created. QEMU can emulate several different models of network card.
1849 Valid values for @var{type} are
1850 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1851 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1852 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1853 Not all devices are supported on all targets. Use @code{-net nic,model=help}
1854 for a list of available devices for your target.
1856 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
1858 @item -net user[,@var{option}][,@var{option}][,...]
1859 Use the user mode network stack which requires no administrator
1860 privilege to run. Valid options are:
1864 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1867 @itemx name=@var{name}
1868 Assign symbolic name for use in monitor commands.
1870 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must
1871 be enabled. If neither is specified both protocols are enabled.
1873 @item net=@var{addr}[/@var{mask}]
1874 Set IP network address the guest will see. Optionally specify the netmask,
1875 either in the form a.b.c.d or as number of valid top-most bits. Default is
1878 @item host=@var{addr}
1879 Specify the guest-visible address of the host. Default is the 2nd IP in the
1880 guest network, i.e. x.x.x.2.
1882 @item ipv6-net=@var{addr}[/@var{int}]
1883 Set IPv6 network address the guest will see (default is fec0::/64). The
1884 network prefix is given in the usual hexadecimal IPv6 address
1885 notation. The prefix size is optional, and is given as the number of
1886 valid top-most bits (default is 64).
1888 @item ipv6-host=@var{addr}
1889 Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in
1890 the guest network, i.e. xxxx::2.
1892 @item restrict=on|off
1893 If this option is enabled, the guest will be isolated, i.e. it will not be
1894 able to contact the host and no guest IP packets will be routed over the host
1895 to the outside. This option does not affect any explicitly set forwarding rules.
1897 @item hostname=@var{name}
1898 Specifies the client hostname reported by the built-in DHCP server.
1900 @item dhcpstart=@var{addr}
1901 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1902 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1904 @item dns=@var{addr}
1905 Specify the guest-visible address of the virtual nameserver. The address must
1906 be different from the host address. Default is the 3rd IP in the guest network,
1909 @item ipv6-dns=@var{addr}
1910 Specify the guest-visible address of the IPv6 virtual nameserver. The address
1911 must be different from the host address. Default is the 3rd IP in the guest
1912 network, i.e. xxxx::3.
1914 @item dnssearch=@var{domain}
1915 Provides an entry for the domain-search list sent by the built-in
1916 DHCP server. More than one domain suffix can be transmitted by specifying
1917 this option multiple times. If supported, this will cause the guest to
1918 automatically try to append the given domain suffix(es) in case a domain name
1919 can not be resolved.
1923 qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
1926 @item tftp=@var{dir}
1927 When using the user mode network stack, activate a built-in TFTP
1928 server. The files in @var{dir} will be exposed as the root of a TFTP server.
1929 The TFTP client on the guest must be configured in binary mode (use the command
1930 @code{bin} of the Unix TFTP client).
1932 @item bootfile=@var{file}
1933 When using the user mode network stack, broadcast @var{file} as the BOOTP
1934 filename. In conjunction with @option{tftp}, this can be used to network boot
1935 a guest from a local directory.
1937 Example (using pxelinux):
1939 qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1942 @item smb=@var{dir}[,smbserver=@var{addr}]
1943 When using the user mode network stack, activate a built-in SMB
1944 server so that Windows OSes can access to the host files in @file{@var{dir}}
1945 transparently. The IP address of the SMB server can be set to @var{addr}. By
1946 default the 4th IP in the guest network is used, i.e. x.x.x.4.
1948 In the guest Windows OS, the line:
1952 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1953 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1955 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
1957 Note that a SAMBA server must be installed on the host OS.
1958 QEMU was tested successfully with smbd versions from Red Hat 9,
1959 Fedora Core 3 and OpenSUSE 11.x.
1961 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1962 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1963 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1964 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1965 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1966 be bound to a specific host interface. If no connection type is set, TCP is
1967 used. This option can be given multiple times.
1969 For example, to redirect host X11 connection from screen 1 to guest
1970 screen 0, use the following:
1974 qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1975 # this host xterm should open in the guest X11 server
1979 To redirect telnet connections from host port 5555 to telnet port on
1980 the guest, use the following:
1984 qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
1985 telnet localhost 5555
1988 Then when you use on the host @code{telnet localhost 5555}, you
1989 connect to the guest telnet server.
1991 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1992 @itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
1993 Forward guest TCP connections to the IP address @var{server} on port @var{port}
1994 to the character device @var{dev} or to a program executed by @var{cmd:command}
1995 which gets spawned for each connection. This option can be given multiple times.
1997 You can either use a chardev directly and have that one used throughout QEMU's
1998 lifetime
, like
in the following example
:
2001 # open
10.10.1.1:4321 on bootup
, connect
10.0.2.100:1234 to it whenever
2002 # the guest accesses it
2003 qemu
-net user
,guestfwd
=tcp
:10.0.2.100:1234-tcp
:10.10.1.1:4321 [...]
2006 Or you can execute a command on every TCP connection established by the guest
,
2007 so that QEMU behaves similar to an inetd process
for that virtual server
:
2010 # call
"netcat 10.10.1.1 4321" on every TCP connection to
10.0.2.100:1234
2011 # and connect the TCP stream to its stdin
/stdout
2012 qemu
-net
'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
2017 Note
: Legacy stand
-alone options
-tftp
, -bootp
, -smb and
-redir are still
2018 processed and applied to
-net user
. Mixing them with the
new configuration
2019 syntax gives undefined results
. Their use
for new applications is discouraged
2020 as they will be removed from future versions
.
2022 @item
-netdev tap
,id
=@
var{id
}[,fd
=@
var{h
}][,ifname
=@
var{name
}][,script
=@
var{file
}][,downscript
=@
var{dfile
}][,br
=@
var{bridge
}][,helper
=@
var{helper
}]
2023 @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
}]
2024 Connect the host TAP network
interface @
var{name
} to VLAN @
var{n
}.
2026 Use the network script @
var{file
} to configure it and the network script
2027 @
var{dfile
} to deconfigure it
. If @
var{name
} is not provided
, the OS
2028 automatically provides one
. The
default network configure script is
2029 @file
{/etc
/qemu
-ifup
} and the
default network deconfigure script is
2030 @file
{/etc
/qemu
-ifdown
}. Use @option
{script
=no
} or @option
{downscript
=no
}
2031 to disable script execution
.
2033 If running QEMU as an unprivileged user
, use the network helper
2034 @
var{helper
} to configure the TAP
interface and attach it to the bridge
.
2035 The
default network helper executable is @file
{/path
/to
/qemu
-bridge
-helper
}
2036 and the
default bridge device is @file
{br0
}.
2038 @option
{fd
}=@
var{h
} can be used to specify the handle of an already
2039 opened host TAP
interface.
2044 #launch a QEMU instance with the
default network script
2045 qemu
-system
-i386 linux
.img
-net nic
-net tap
2049 #launch a QEMU instance with two NICs
, each one connected
2051 qemu
-system
-i386 linux
.img \
2052 -net nic
,vlan
=0 -net tap
,vlan
=0,ifname
=tap0 \
2053 -net nic
,vlan
=1 -net tap
,vlan
=1,ifname
=tap1
2057 #launch a QEMU instance with the
default network helper to
2058 #connect a TAP device to bridge br0
2059 qemu
-system
-i386 linux
.img \
2060 -net nic
-net tap
,"helper=/path/to/qemu-bridge-helper"
2063 @item
-netdev bridge
,id
=@
var{id
}[,br
=@
var{bridge
}][,helper
=@
var{helper
}]
2064 @itemx
-net bridge
[,vlan
=@
var{n
}][,name
=@
var{name
}][,br
=@
var{bridge
}][,helper
=@
var{helper
}]
2065 Connect a host TAP network
interface to a host bridge device
.
2067 Use the network helper @
var{helper
} to configure the TAP
interface and
2068 attach it to the bridge
. The
default network helper executable is
2069 @file
{/path
/to
/qemu
-bridge
-helper
} and the
default bridge
2070 device is @file
{br0
}.
2075 #launch a QEMU instance with the
default network helper to
2076 #connect a TAP device to bridge br0
2077 qemu
-system
-i386 linux
.img
-net bridge
-net nic
,model
=virtio
2081 #launch a QEMU instance with the
default network helper to
2082 #connect a TAP device to bridge qemubr0
2083 qemu
-system
-i386 linux
.img
-net bridge
,br
=qemubr0
-net nic
,model
=virtio
2086 @item
-netdev socket
,id
=@
var{id
}[,fd
=@
var{h
}][,listen
=[@
var{host
}]:@
var{port
}][,connect
=@
var{host
}:@
var{port
}]
2087 @itemx
-net socket
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}] [,listen
=[@
var{host
}]:@
var{port
}][,connect
=@
var{host
}:@
var{port
}]
2089 Connect the VLAN @
var{n
} to a remote VLAN
in another QEMU virtual
2090 machine
using a TCP socket connection
. If @option
{listen
} is
2091 specified
, QEMU waits
for incoming connections on @
var{port
}
2092 (@
var{host
} is optional
). @option
{connect
} is used to connect to
2093 another QEMU instance
using the @option
{listen
} option
. @option
{fd
}=@
var{h
}
2094 specifies an already opened TCP socket
.
2098 # launch a first QEMU instance
2099 qemu
-system
-i386 linux
.img \
2100 -net nic
,macaddr
=52:54:00:12:34:56 \
2101 -net socket
,listen
=:1234
2102 # connect the VLAN
0 of
this instance to the VLAN
0
2103 # of the first instance
2104 qemu
-system
-i386 linux
.img \
2105 -net nic
,macaddr
=52:54:00:12:34:57 \
2106 -net socket
,connect
=127.0.0.1:1234
2109 @item
-netdev socket
,id
=@
var{id
}[,fd
=@
var{h
}][,mcast
=@
var{maddr
}:@
var{port
}[,localaddr
=@
var{addr
}]]
2110 @itemx
-net socket
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}][,mcast
=@
var{maddr
}:@
var{port
}[,localaddr
=@
var{addr
}]]
2112 Create a VLAN @
var{n
} shared with another QEMU virtual
2113 machines
using a UDP multicast socket
, effectively making a bus
for
2114 every QEMU with same multicast address @
var{maddr
} and @
var{port
}.
2118 Several QEMU can be running on different hosts and share same
bus (assuming
2119 correct multicast setup
for these hosts
).
2121 mcast support is compatible with User Mode
Linux (argument @option
{eth@
var{N
}=mcast
}), see
2122 @url
{http
://user-mode-linux.sf.net}.
2124 Use @option
{fd
=h
} to specify an already opened UDP multicast socket
.
2129 # launch one QEMU instance
2130 qemu
-system
-i386 linux
.img \
2131 -net nic
,macaddr
=52:54:00:12:34:56 \
2132 -net socket
,mcast
=230.0.0.1:1234
2133 # launch another QEMU instance on same
"bus"
2134 qemu
-system
-i386 linux
.img \
2135 -net nic
,macaddr
=52:54:00:12:34:57 \
2136 -net socket
,mcast
=230.0.0.1:1234
2137 # launch yet another QEMU instance on same
"bus"
2138 qemu
-system
-i386 linux
.img \
2139 -net nic
,macaddr
=52:54:00:12:34:58 \
2140 -net socket
,mcast
=230.0.0.1:1234
2143 Example (User Mode Linux compat
.):
2145 # launch QEMU
instance (note mcast address selected
2147 qemu-system-i386 linux.img \
2148 -net nic,macaddr=52:54:00:12:34:56 \
2149 -net socket,mcast=239.192.168.1:1102
2151 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
2154 Example (send packets from host's
1.2.3.4):
2156 qemu
-system
-i386 linux
.img \
2157 -net nic
,macaddr
=52:54:00:12:34:56 \
2158 -net socket
,mcast
=239.192.168.1:1102,localaddr
=1.2.3.4
2161 @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
}]
2162 @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
}]
2163 Connect VLAN @
var{n
} to L2TPv3 pseudowire
. L2TPv3 (RFC3391
) is a popular
2164 protocol to transport
Ethernet (and other Layer
2) data frames between
2165 two systems
. It is present
in routers
, firewalls and the Linux kernel
2166 (from version
3.3 onwards
).
2168 This transport allows a VM to communicate to another VM
, router or firewall directly
.
2170 @item src
=@
var{srcaddr
}
2171 source
address (mandatory
)
2172 @item dst
=@
var{dstaddr
}
2173 destination
address (mandatory
)
2175 select udp
encapsulation (default is ip
).
2176 @item srcport
=@
var{srcport
}
2178 @item dstport
=@
var{dstport
}
2179 destination udp port
.
2181 force v6
, otherwise defaults to v4
.
2182 @item rxcookie
=@
var{rxcookie
}
2183 @itemx txcookie
=@
var{txcookie
}
2184 Cookies are a weak form of security
in the l2tpv3 specification
.
2185 Their
function is mostly to prevent misconfiguration
. By
default they are
32
2188 Set cookie size to
64 bit instead of the
default 32
2190 Force a
'cut-down' L2TPv3 with no counter as
in
2191 draft
-mkonstan
-l2tpext
-keyed
-ipv6
-tunnel
-00
2193 Work around broken counter handling
in peer
. This may also help on
2194 networks which have packet reorder
.
2195 @item offset
=@
var{offset
}
2196 Add an extra offset between header and data
2198 For example
, to attach a VM running on host
4.3.2.1 via L2TPv3 to the bridge br
-lan
2199 on the remote Linux host
1.2.3.4:
2201 # Setup tunnel on linux host
using raw ip as encapsulation
2203 ip l2tp add tunnel remote
4.3.2.1 local
1.2.3.4 tunnel_id
1 peer_tunnel_id
1 \
2204 encap udp udp_sport
16384 udp_dport
16384
2205 ip l2tp add session tunnel_id
1 name vmtunnel0 session_id \
2206 0xFFFFFFFF peer_session_id
0xFFFFFFFF
2207 ifconfig vmtunnel0 mtu
1500
2208 ifconfig vmtunnel0 up
2209 brctl addif br
-lan vmtunnel0
2213 # launch QEMU instance
- if your network has reorder or is very lossy add
,pincounter
2215 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
2220 @item
-netdev vde
,id
=@
var{id
}[,sock
=@
var{socketpath
}][,port
=@
var{n
}][,group
=@
var{groupname
}][,mode
=@
var{octalmode
}]
2221 @itemx
-net vde
[,vlan
=@
var{n
}][,name
=@
var{name
}][,sock
=@
var{socketpath
}] [,port
=@
var{n
}][,group
=@
var{groupname
}][,mode
=@
var{octalmode
}]
2222 Connect VLAN @
var{n
} to PORT @
var{n
} of a vde
switch running on host and
2223 listening
for incoming connections on @
var{socketpath
}. Use GROUP @
var{groupname
}
2224 and MODE @
var{octalmode
} to change
default ownership and permissions
for
2225 communication port
. This option is only available
if QEMU has been compiled
2226 with vde support enabled
.
2231 vde_switch
-F
-sock
/tmp
/myswitch
2232 # launch QEMU instance
2233 qemu
-system
-i386 linux
.img
-net nic
-net vde
,sock
=/tmp
/myswitch
2236 @item
-netdev hubport
,id
=@
var{id
},hubid
=@
var{hubid
}
2238 Create a hub port on QEMU
"vlan" @
var{hubid
}.
2240 The hubport netdev lets you connect a NIC to a QEMU
"vlan" instead of a single
2241 netdev
. @code
{-net
} and @code
{-device
} with parameter @option
{vlan
} create the
2242 required hub automatically
.
2244 @item
-netdev vhost
-user
,chardev
=@
var{id
}[,vhostforce
=on|off
][,queues
=n
]
2246 Establish a vhost
-user netdev
, backed by a chardev @
var{id
}. The chardev should
2247 be a unix domain socket backed one
. The vhost
-user uses a specifically defined
2248 protocol to pass vhost ioctl replacement messages to an application on the other
2249 end of the socket
. On non
-MSIX guests
, the feature can be forced with
2250 @
var{vhostforce
}. Use
'queues=@var{n}' to specify the number of queues to
2251 be created
for multiqueue vhost
-user
.
2255 qemu
-m
512 -object memory
-backend
-file
,id
=mem
,size
=512M
,mem
-path
=/hugetlbfs
,share
=on \
2256 -numa node
,memdev
=mem \
2257 -chardev socket
,id
=chr0
,path
=/path
/to
/socket \
2258 -netdev type
=vhost
-user
,id
=net0
,chardev
=chr0 \
2259 -device virtio
-net
-pci
,netdev
=net0
2262 @item
-net dump
[,vlan
=@
var{n
}][,file
=@
var{file
}][,len
=@
var{len
}]
2263 Dump network traffic on VLAN @
var{n
} to file @
var{file
} (@file
{qemu
-vlan0
.pcap
} by
default).
2264 At most @
var{len
} bytes (64k by
default) per packet are stored
. The file format is
2265 libpcap
, so it can be analyzed with tools such as tcpdump or Wireshark
.
2266 Note
: For devices created with
'-netdev', use
'-object filter-dump,...' instead
.
2269 Indicate that no network devices should be configured
. It is used to
2270 override the
default configuration (@option
{-net nic
-net user
}) which
2271 is activated
if no @option
{-net
} options are provided
.
2279 DEFHEADING(Character device options
)
2282 The general form of a character device option is
:
2286 DEF("chardev", HAS_ARG
, QEMU_OPTION_chardev
,
2288 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2289 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
2290 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n"
2291 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n"
2292 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n"
2293 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n"
2294 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
2295 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
2296 " [,logfile=PATH][,logappend=on|off]\n"
2297 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2298 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
2299 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2300 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n"
2301 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2302 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2304 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2305 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2307 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2308 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n"
2310 #ifdef CONFIG_BRLAPI
2311 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2313 #
if defined(__linux__
) ||
defined(__sun__
) ||
defined(__FreeBSD__
) \
2314 ||
defined(__NetBSD__
) ||
defined(__OpenBSD__
) ||
defined(__DragonFly__
)
2315 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2316 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2318 #
if defined(__linux__
) ||
defined(__FreeBSD__
) ||
defined(__DragonFly__
)
2319 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2320 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2322 #
if defined(CONFIG_SPICE
)
2323 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2324 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2330 @item
-chardev @
var{backend
} ,id
=@
var{id
} [,mux
=on|off
] [,@
var{options
}]
2351 The specific backend will determine the applicable options
.
2353 Use
"-chardev help" to print all available chardev backend types
.
2355 All devices must have an id
, which can be any string up to
127 characters long
.
2356 It is used to uniquely identify
this device
in other command line directives
.
2358 A character device may be used
in multiplexing mode by multiple front
-ends
.
2359 Specify @option
{mux
=on
} to enable
this mode
.
2360 A multiplexer is a
"1:N" device
, and
here the
"1" end is your specified chardev
2361 backend
, and the
"N" end is the various parts of QEMU that can talk to a chardev
.
2362 If you create a chardev with @option
{id
=myid
} and @option
{mux
=on
}, QEMU will
2363 create a multiplexer with your specified ID
, and you can then configure multiple
2364 front ends to use that chardev ID
for their input
/output
. Up to four different
2365 front ends can be connected to a single multiplexed chardev
. (Without
2366 multiplexing enabled
, a chardev can only be used by a single front end
.)
2367 For instance you could use
this to allow a single stdio chardev to be used by
2368 two serial ports and the QEMU monitor
:
2371 -chardev stdio
,mux
=on
,id
=char0 \
2372 -mon chardev
=char0
,mode
=readline \
2373 -serial chardev
:char0 \
2374 -serial chardev
:char0
2377 You can have more than one multiplexer
in a system configuration
; for instance
2378 you could have a TCP port multiplexed between UART
0 and UART
1, and stdio
2379 multiplexed between the QEMU monitor and a parallel port
:
2382 -chardev stdio
,mux
=on
,id
=char0 \
2383 -mon chardev
=char0
,mode
=readline \
2384 -parallel chardev
:char0 \
2385 -chardev tcp
,...,mux
=on
,id
=char1 \
2386 -serial chardev
:char1 \
2387 -serial chardev
:char1
2390 When you
're using a multiplexed character device, some escape sequences are
2391 interpreted in the input. @xref{mux_keys, Keys in the character backend
2394 Note that some other command line options may implicitly create multiplexed
2395 character backends; for instance @option{-serial mon:stdio} creates a
2396 multiplexed stdio backend connected to the serial port and the QEMU monitor,
2397 and @option{-nographic} also multiplexes the console and the monitor to
2400 There is currently no support for multiplexing in the other direction
2401 (where a single QEMU front end takes input and output from multiple chardevs).
2403 Every backend supports the @option{logfile} option, which supplies the path
2404 to a file to record all data transmitted via the backend. The @option{logappend}
2405 option controls whether the log file will be truncated or appended to when
2408 Further options to each backend are described below.
2410 @item -chardev null ,id=@var{id}
2411 A void device. This device will not emit any data, and will drop any data it
2412 receives. The null backend does not take any options.
2414 @item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}] [,tls-creds=@var{id}]
2416 Create a two-way stream socket, which can be either a TCP or a unix socket. A
2417 unix socket will be created if @option{path} is specified. Behaviour is
2418 undefined if TCP options are specified for a unix socket.
2420 @option{server} specifies that the socket shall be a listening socket.
2422 @option{nowait} specifies that QEMU should not block waiting for a client to
2423 connect to a listening socket.
2425 @option{telnet} specifies that traffic on the socket should interpret telnet
2428 @option{reconnect} sets the timeout for reconnecting on non-server sockets when
2429 the remote end goes away. qemu will delay this many seconds and then attempt
2430 to reconnect. Zero disables reconnecting, and is the default.
2432 @option{tls-creds} requests enablement of the TLS protocol for encryption,
2433 and specifies the id of the TLS credentials to use for the handshake. The
2434 credentials must be previously created with the @option{-object tls-creds}
2437 TCP and unix socket options are given below:
2441 @item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
2443 @option{host} for a listening socket specifies the local address to be bound.
2444 For a connecting socket species the remote host to connect to. @option{host} is
2445 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
2447 @option{port} for a listening socket specifies the local port to be bound. For a
2448 connecting socket specifies the port on the remote host to connect to.
2449 @option{port} can be given as either a port number or a service name.
2450 @option{port} is required.
2452 @option{to} is only relevant to listening sockets. If it is specified, and
2453 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
2454 to and including @option{to} until it succeeds. @option{to} must be specified
2457 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2458 If neither is specified the socket may use either protocol.
2460 @option{nodelay} disables the Nagle algorithm.
2462 @item unix options: path=@var{path}
2464 @option{path} specifies the local path of the unix socket. @option{path} is
2469 @item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
2471 Sends all traffic from the guest to a remote host over UDP.
2473 @option{host} specifies the remote host to connect to. If not specified it
2474 defaults to @code{localhost}.
2476 @option{port} specifies the port on the remote host to connect to. @option{port}
2479 @option{localaddr} specifies the local address to bind to. If not specified it
2480 defaults to @code{0.0.0.0}.
2482 @option{localport} specifies the local port to bind to. If not specified any
2483 available local port will be used.
2485 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2486 If neither is specified the device may use either protocol.
2488 @item -chardev msmouse ,id=@var{id}
2490 Forward QEMU's emulated msmouse events to the guest
. @option
{msmouse
} does not
2493 @item
-chardev vc
,id
=@
var{id
} [[,width
=@
var{width
}] [,height
=@
var{height
}]] [[,cols
=@
var{cols
}] [,rows
=@
var{rows
}]]
2495 Connect to a QEMU text console
. @option
{vc
} may optionally be given a specific
2498 @option
{width
} and @option
{height
} specify the width and height respectively of
2499 the console
, in pixels
.
2501 @option
{cols
} and @option
{rows
} specify that the console be sized to fit a text
2502 console with the given dimensions
.
2504 @item
-chardev ringbuf
,id
=@
var{id
} [,size
=@
var{size
}]
2506 Create a ring buffer with fixed size @option
{size
}.
2507 @
var{size
} must be a power of two and defaults to @code
{64K
}.
2509 @item
-chardev file
,id
=@
var{id
} ,path
=@
var{path
}
2511 Log all traffic received from the guest to a file
.
2513 @option
{path
} specifies the path of the file to be opened
. This file will be
2514 created
if it does not already exist
, and overwritten
if it does
. @option
{path
}
2517 @item
-chardev pipe
,id
=@
var{id
} ,path
=@
var{path
}
2519 Create a two
-way connection to the guest
. The behaviour differs slightly between
2520 Windows hosts and other hosts
:
2522 On Windows
, a single duplex pipe will be created at
2523 @file
{\\.pipe\@option
{path
}}.
2525 On other hosts
, 2 pipes will be created called @file
{@option
{path
}.in} and
2526 @file
{@option
{path
}.out
}. Data written to @file
{@option
{path
}.in} will be
2527 received by the guest
. Data written by the guest can be read from
2528 @file
{@option
{path
}.out
}. QEMU will not create these fifos
, and requires them to
2531 @option
{path
} forms part of the pipe path as described above
. @option
{path
} is
2534 @item
-chardev console
,id
=@
var{id
}
2536 Send traffic from the guest to QEMU
's standard output. @option{console} does not
2539 @option{console} is only available on Windows hosts.
2541 @item -chardev serial ,id=@var{id} ,path=@option{path}
2543 Send traffic from the guest to a serial device on the host.
2545 On Unix hosts serial will actually accept any tty device,
2546 not only serial lines.
2548 @option{path} specifies the name of the serial device to open.
2550 @item -chardev pty ,id=@var{id}
2552 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2553 not take any options.
2555 @option{pty} is not available on Windows hosts.
2557 @item -chardev stdio ,id=@var{id} [,signal=on|off]
2558 Connect to standard input and standard output of the QEMU process.
2560 @option{signal} controls if signals are enabled on the terminal, that includes
2561 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2562 default, use @option{signal=off} to disable it.
2564 @item -chardev braille ,id=@var{id}
2566 Connect to a local BrlAPI server. @option{braille} does not take any options.
2568 @item -chardev tty ,id=@var{id} ,path=@var{path}
2570 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2571 DragonFlyBSD hosts. It is an alias for @option{serial}.
2573 @option{path} specifies the path to the tty. @option{path} is required.
2575 @item -chardev parallel ,id=@var{id} ,path=@var{path}
2576 @itemx -chardev parport ,id=@var{id} ,path=@var{path}
2578 @option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2580 Connect to a local parallel port.
2582 @option{path} specifies the path to the parallel port device. @option{path} is
2585 @item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2587 @option{spicevmc} is only available when spice support is built in.
2589 @option{debug} debug level for spicevmc
2591 @option{name} name of spice channel to connect to
2593 Connect to a spice virtual machine channel, such as vdiport.
2595 @item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2597 @option{spiceport} is only available when spice support is built in.
2599 @option{debug} debug level for spicevmc
2601 @option{name} name of spice port to connect to
2603 Connect to a spice port, allowing a Spice client to handle the traffic
2604 identified by a name (preferably a fqdn).
2612 DEFHEADING(Device URL Syntax)
2615 In addition to using normal file images for the emulated storage devices,
2616 QEMU can also use networked resources such as iSCSI devices. These are
2617 specified using a special URL syntax.
2621 iSCSI support allows QEMU to access iSCSI resources directly and use as
2622 images for the guest storage. Both disk and cdrom images are supported.
2624 Syntax for specifying iSCSI LUNs is
2625 ``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
2627 By default qemu will use the iSCSI initiator-name
2628 'iqn
.2008-11.org
.linux
-kvm
[:<name
>]' but this can also be set from the command
2629 line or a configuration file.
2631 Since version Qemu 2.4 it is possible to specify a iSCSI request timeout to detect
2632 stalled requests and force a reestablishment of the session. The timeout
2633 is specified in seconds. The default is 0 which means no timeout. Libiscsi
2634 1.15.0 or greater is required for this feature.
2636 Example (without authentication):
2638 qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
2639 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
2640 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2643 Example (CHAP username/password via URL):
2645 qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
2648 Example (CHAP username/password via environment variables):
2650 LIBISCSI_CHAP_USERNAME="user" \
2651 LIBISCSI_CHAP_PASSWORD="password" \
2652 qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2655 iSCSI support is an optional feature of QEMU and only available when
2656 compiled and linked against libiscsi.
2658 DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
2659 "-iscsi [user=user][,password=password]\n"
2660 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
2661 " [,initiator-name=initiator-iqn][,id=target-iqn]\n"
2662 " [,timeout=timeout]\n"
2663 " iSCSI session parameters\n", QEMU_ARCH_ALL)
2666 iSCSI parameters such as username and password can also be specified via
2667 a configuration file. See qemu-doc for more information and examples.
2670 QEMU supports NBD (Network Block Devices) both using TCP protocol as well
2671 as Unix Domain Sockets.
2673 Syntax for specifying a NBD device using TCP
2674 ``nbd:<server-ip>:<port>[:exportname=<export>]''
2676 Syntax for specifying a NBD device using Unix Domain Sockets
2677 ``nbd:unix:<domain-socket>[:exportname=<export>]''
2682 qemu-system-i386 --drive file=nbd:192.0.2.1:30000
2685 Example for Unix Domain Sockets
2687 qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket
2691 QEMU supports SSH (Secure Shell) access to remote disks.
2695 qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img
2696 qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img
2699 Currently authentication must be done using ssh-agent. Other
2700 authentication methods may be supported in future.
2703 Sheepdog is a distributed storage system for QEMU.
2704 QEMU supports using either local sheepdog devices or remote networked
2707 Syntax for specifying a sheepdog device
2709 sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag]
2714 qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine
2717 See also @url{https://sheepdog.github.io/sheepdog/}.
2720 GlusterFS is a user space distributed file system.
2721 QEMU supports the use of GlusterFS volumes for hosting VM disk images using
2722 TCP, Unix Domain Sockets and RDMA transport protocols.
2724 Syntax for specifying a VM disk image on GlusterFS volume is
2728 gluster[+type]://[host[:port]]/volume/path[?socket=...][,debug=N][,logfile=...]
2731 'json
:@
{"driver":"qcow2","file":@
{"driver":"gluster","volume":"testvol","path":"a.img","debug":N
,"logfile":"...",
2732 @
"server":[@
{"type":"tcp","host":"...","port":"..."@
},
2733 @ @
{"type":"unix","socket":"..."@
}]@
}@
}'
2740 qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img,
2741 @ file.debug=9,file.logfile=/var/log/qemu-gluster.log
2744 qemu-system-x86_64 'json
:@
{"driver":"qcow2",
2745 @
"file":@
{"driver":"gluster",
2746 @
"volume":"testvol","path":"a.img",
2747 @
"debug":9,"logfile":"/var/log/qemu-gluster.log",
2748 @
"server":[@
{"type":"tcp","host":"1.2.3.4","port":24007@
},
2749 @ @
{"type":"unix","socket":"/var/run/glusterd.socket"@
}]@
}@
}'
2750 qemu-system-x86_64 -drive driver=qcow2,file.driver=gluster,file.volume=testvol,file.path=/path/a.img,
2751 @ file.debug=9,file.logfile=/var/log/qemu-gluster.log,
2752 @ file.server.0.type=tcp,file.server.0.host=1.2.3.4,file.server.0.port=24007,
2753 @ file.server.1.type=unix,file.server.1.socket=/var/run/glusterd.socket
2756 See also @url{http://www.gluster.org}.
2758 @item HTTP/HTTPS/FTP/FTPS
2759 QEMU supports read-only access to files accessed over http(s) and ftp(s).
2761 Syntax using a single filename:
2763 <protocol>://[<username>[:<password>]@@]<host>/<path>
2769 'http
', 'https
', 'ftp
', or 'ftps
'.
2772 Optional username for authentication to the remote server.
2775 Optional password for authentication to the remote server.
2778 Address of the remote server.
2781 Path on the remote server, including any query string.
2784 The following options are also supported:
2787 The full URL when passing options to the driver explicitly.
2790 The amount of data to read ahead with each range request to the remote server.
2791 This value may optionally have the suffix 'T
', 'G
', 'M
', 'K
', 'k
' or 'b
'. If it
2792 does not have a suffix, it will be assumed to be in bytes. The value must be a
2793 multiple of 512 bytes. It defaults to 256k.
2796 Whether to verify the remote server's certificate when connecting over SSL
. It
2797 can have the value
'on' or
'off'. It defaults to
'on'.
2800 Send
this cookie (it can also be a list of cookies separated by
';') with
2801 each outgoing request
. Only supported when
using protocols such as HTTP
2802 which support cookies
, otherwise ignored
.
2805 Set the timeout
in seconds of the CURL connection
. This timeout is the time
2806 that CURL waits
for a response from the remote server to get the size of the
2807 image to be downloaded
. If not set
, the
default timeout of
5 seconds is used
.
2810 Note that when passing options to qemu explicitly
, @option
{driver
} is the value
2813 Example
: boot from a remote Fedora
20 live ISO image
2815 qemu
-system
-x86_64
--drive media
=cdrom
,file
=http
://dl.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
2817 qemu
-system
-x86_64
--drive media
=cdrom
,file
.driver
=http
,file
.url
=http
://dl.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
2820 Example
: boot from a remote Fedora
20 cloud image
using a local overlay
for
2821 writes
, copy
-on
-read
, and a readahead of
64k
2823 qemu
-img create
-f qcow2
-o backing_file
='json:@{"file.driver":"http",, "file.url":"https://dl.fedoraproject.org/pub/fedora/linux/releases/20/Images/x86_64/Fedora-x86_64-20-20131211.1-sda.qcow2",, "file.readahead":"64k"@}' /tmp
/Fedora
-x86_64
-20-20131211.1-sda
.qcow2
2825 qemu
-system
-x86_64
-drive file
=/tmp
/Fedora
-x86_64
-20-20131211.1-sda
.qcow2
,copy
-on
-read
=on
2828 Example
: boot from an image stored on a VMware vSphere server with a self
-signed
2829 certificate
using a local overlay
for writes
, a readahead of
64k and a timeout
2832 qemu
-img create
-f qcow2
-o backing_file
='json:@{"file.driver":"https",, "file.url":"https://user:password@@vsphere.example.com/folder/test/test-flat.vmdk?dcPath=Datacenter&dsName=datastore1",, "file.sslverify":"off",, "file.readahead":"64k",, "file.timeout":10@}' /tmp
/test
.qcow2
2834 qemu
-system
-x86_64
-drive file
=/tmp
/test
.qcow2
2842 DEFHEADING(Bluetooth(R
) options
)
2847 DEF("bt", HAS_ARG
, QEMU_OPTION_bt
, \
2848 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \
2849 "-bt hci,host[:id]\n" \
2850 " use host's HCI with the given name\n" \
2851 "-bt hci[,vlan=n]\n" \
2852 " emulate a standard HCI in virtual scatternet 'n'\n" \
2853 "-bt vhci[,vlan=n]\n" \
2854 " add host computer to virtual scatternet 'n' using VHCI\n" \
2855 "-bt device:dev[,vlan=n]\n" \
2856 " emulate a bluetooth device 'dev' in scatternet 'n'\n",
2861 Defines the
function of the corresponding Bluetooth HCI
. -bt options
2862 are matched with the HCIs present
in the chosen machine type
. For
2863 example when emulating a machine with only one HCI built into it
, only
2864 the first @code
{-bt hci
[...]} option is valid and defines the HCI
's
2865 logic. The Transport Layer is decided by the machine type. Currently
2866 the machines @code{n800} and @code{n810} have one HCI and all other
2870 The following three types are recognized:
2874 (default) The corresponding Bluetooth HCI assumes no internal logic
2875 and will not respond to any HCI commands or emit events.
2877 @item -bt hci,host[:@var{id}]
2878 (@code{bluez} only) The corresponding HCI passes commands / events
2879 to / from the physical HCI identified by the name @var{id} (default:
2880 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
2881 capable systems like Linux.
2883 @item -bt hci[,vlan=@var{n}]
2884 Add a virtual, standard HCI that will participate in the Bluetooth
2885 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
2886 VLANs, devices inside a bluetooth network @var{n} can only communicate
2887 with other devices in the same network (scatternet).
2890 @item -bt vhci[,vlan=@var{n}]
2891 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2892 to the host bluetooth stack instead of to the emulated target. This
2893 allows the host and target machines to participate in a common scatternet
2894 and communicate. Requires the Linux @code{vhci} driver installed. Can
2895 be used as following:
2898 qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2901 @item -bt device:@var{dev}[,vlan=@var{n}]
2902 Emulate a bluetooth device @var{dev} and place it in network @var{n}
2903 (default @code{0}). QEMU can only emulate one type of bluetooth devices
2908 Virtual wireless keyboard implementing the HIDP bluetooth profile.
2918 DEFHEADING(TPM device options)
2920 DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
2921 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
2922 " use path to provide path to a character device; default is /dev/tpm0\n"
2923 " use cancel-path to provide path to TPM's cancel sysfs entry
; if\n"
2924 " not provided it will be searched
for in /sys
/class/misc
/tpm?
/device
\n",
2928 The general form of a TPM device option is:
2931 @item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
2933 Backend type must be:
2934 @option{passthrough}.
2936 The specific backend type will determine the applicable options.
2937 The @code{-tpmdev} option creates the TPM backend and requires a
2938 @code{-device} option that specifies the TPM frontend interface model.
2940 Options to each backend are described below.
2942 Use 'help' to print all available TPM backend types.
2947 @item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path}
2949 (Linux-host only) Enable access to the host's TPM using the passthrough
2952 @option{path} specifies the path to the host's TPM device, i.e., on
2953 a Linux host this would be @code{/dev/tpm0}.
2954 @option{path} is optional and by default @code{/dev/tpm0} is used.
2956 @option{cancel-path} specifies the path to the host TPM device's sysfs
2957 entry allowing for cancellation of an ongoing TPM command.
2958 @option{cancel-path} is optional and by default QEMU will search for the
2961 Some notes about using the host's TPM with the passthrough driver:
2963 The TPM device accessed by the passthrough driver must not be
2964 used by any other application on the host.
2966 Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
2967 the VM's firmware (BIOS/UEFI) will not be able to initialize the
2968 TPM again and may therefore not show a TPM-specific menu that would
2969 otherwise allow the user to configure the TPM, e.g., allow the user to
2970 enable/disable or activate/deactivate the TPM.
2971 Further, if TPM ownership is released from within a VM then the host's TPM
2972 will get disabled and deactivated. To enable and activate the
2973 TPM again afterwards, the host has to be rebooted and the user is
2974 required to enter the firmware's menu to enable and activate the TPM.
2975 If the TPM is left disabled and/or deactivated most TPM commands will fail.
2977 To create a passthrough TPM use the following two options:
2979 -tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
2981 Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
2982 @code{tpmdev=tpm0} in the device option.
2992 DEFHEADING(Linux/Multiboot boot specific)
2995 When using these options, you can use a given Linux or Multiboot
2996 kernel without installing it in the disk image. It can be useful
2997 for easier testing of various kernels.
3002 DEF("kernel
", HAS_ARG, QEMU_OPTION_kernel, \
3003 "-kernel bzImage use
'bzImage' as kernel image
\n", QEMU_ARCH_ALL)
3005 @item -kernel @var{bzImage}
3007 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
3008 or in multiboot format.
3011 DEF("append
", HAS_ARG, QEMU_OPTION_append, \
3012 "-append cmdline use
'cmdline' as kernel command line
\n", QEMU_ARCH_ALL)
3014 @item -append @var{cmdline}
3016 Use @var{cmdline} as kernel command line
3019 DEF("initrd
", HAS_ARG, QEMU_OPTION_initrd, \
3020 "-initrd file use
'file' as initial ram disk
\n", QEMU_ARCH_ALL)
3022 @item -initrd @var{file}
3024 Use @var{file} as initial ram disk.
3026 @item -initrd "@
var{file1
} arg
=foo
,@
var{file2
}"
3028 This syntax is only available with multiboot.
3030 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
3034 DEF("dtb
", HAS_ARG, QEMU_OPTION_dtb, \
3035 "-dtb file use
'file' as device tree image
\n", QEMU_ARCH_ALL)
3037 @item -dtb @var{file}
3039 Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
3048 DEFHEADING(Debug/Expert options)
3053 DEF("fw_cfg
", HAS_ARG, QEMU_OPTION_fwcfg,
3054 "-fw_cfg
[name
=]<name
>,file
=<file
>\n"
3055 " add named fw_cfg entry with contents from file
\n"
3056 "-fw_cfg
[name
=]<name
>,string
=<str
>\n"
3057 " add named fw_cfg entry with contents from string
\n",
3061 @item -fw_cfg [name=]@var{name},file=@var{file}
3063 Add named fw_cfg entry with contents from file @var{file}.
3065 @item -fw_cfg [name=]@var{name},string=@var{str}
3066 Add named fw_cfg entry with contents from string @var{str}.
3068 The terminating NUL character of the contents of @var{str} will not be
3069 included as part of the fw_cfg item data. To insert contents with
3070 embedded NUL characters, you have to use the @var{file} parameter.
3072 The fw_cfg entries are passed by QEMU through to the guest.
3076 -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin
3078 creates an fw_cfg entry named opt/com.mycompany/blob with contents
3083 DEF("serial
", HAS_ARG, QEMU_OPTION_serial, \
3084 "-serial dev redirect the serial port to char device
'dev'\n",
3087 @item -serial @var{dev}
3089 Redirect the virtual serial port to host character device
3090 @var{dev}. The default device is @code{vc} in graphical mode and
3091 @code{stdio} in non graphical mode.
3093 This option can be used several times to simulate up to 4 serial
3096 Use @code{-serial none} to disable all serial ports.
3098 Available character devices are:
3100 @item vc[:@var{W}x@var{H}]
3101 Virtual console. Optionally, a width and height can be given in pixel with
3105 It is also possible to specify width or height in characters:
3110 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
3112 No device is allocated.
3115 @item chardev:@var{id}
3116 Use a named character device defined with the @code{-chardev} option.
3118 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
3119 parameters are set according to the emulated ones.
3120 @item /dev/parport@var{N}
3121 [Linux only, parallel port only] Use host parallel port
3122 @var{N}. Currently SPP and EPP parallel port features can be used.
3123 @item file:@var{filename}
3124 Write output to @var{filename}. No character can be read.
3126 [Unix only] standard input/output
3127 @item pipe:@var{filename}
3128 name pipe @var{filename}
3130 [Windows only] Use host serial port @var{n}
3131 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
3132 This implements UDP Net Console.
3133 When @var{remote_host} or @var{src_ip} are not specified
3134 they default to @code{0.0.0.0}.
3135 When not using a specified @var{src_port} a random port is automatically chosen.
3137 If you just want a simple readonly console you can use @code{netcat} or
3138 @code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
3139 @code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
3140 will appear in the netconsole session.
3142 If you plan to send characters back via netconsole or you want to stop
3143 and start QEMU a lot of times, you should have QEMU use the same
3144 source port each time by using something like @code{-serial
3145 udp::4555@@:4556} to QEMU. Another approach is to use a patched
3146 version of netcat which can listen to a TCP port and send and receive
3147 characters via udp. If you have a patched version of netcat which
3148 activates telnet remote echo and single char transfer, then you can
3149 use the following options to set up a netcat redirector to allow
3150 telnet on port 5555 to access the QEMU port.
3153 -serial udp::4555@@:4556
3154 @item netcat options:
3155 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
3156 @item telnet options:
3160 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}]
3161 The TCP Net Console has two modes of operation. It can send the serial
3162 I/O to a location or wait for a connection from a location. By default
3163 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
3164 the @var{server} option QEMU will wait for a client socket application
3165 to connect to the port before continuing, unless the @code{nowait}
3166 option was specified. The @code{nodelay} option disables the Nagle buffering
3167 algorithm. The @code{reconnect} option only applies if @var{noserver} is
3168 set, if the connection goes down it will attempt to reconnect at the
3169 given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only
3170 one TCP connection at a time is accepted. You can use @code{telnet} to
3171 connect to the corresponding character device.
3173 @item Example to send tcp console to 192.168.0.2 port 4444
3174 -serial tcp:192.168.0.2:4444
3175 @item Example to listen and wait on port 4444 for connection
3176 -serial tcp::4444,server
3177 @item Example to not wait and listen on ip 192.168.0.100 port 4444
3178 -serial tcp:192.168.0.100:4444,server,nowait
3181 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
3182 The telnet protocol is used instead of raw tcp sockets. The options
3183 work the same as if you had specified @code{-serial tcp}. The
3184 difference is that the port acts like a telnet server or client using
3185 telnet option negotiation. This will also allow you to send the
3186 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
3187 sequence. Typically in unix telnet you do it with Control-] and then
3188 type "send
break" followed by pressing the enter key.
3190 @item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}]
3191 A unix domain socket is used instead of a tcp socket. The option works the
3192 same as if you had specified @code{-serial tcp} except the unix domain socket
3193 @var{path} is used for connections.
3195 @item mon:@var{dev_string}
3196 This is a special option to allow the monitor to be multiplexed onto
3197 another serial port. The monitor is accessed with key sequence of
3198 @key{Control-a} and then pressing @key{c}.
3199 @var{dev_string} should be any one of the serial devices specified
3200 above. An example to multiplex the monitor onto a telnet server
3201 listening on port 4444 would be:
3203 @item -serial mon:telnet::4444,server,nowait
3205 When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
3206 QEMU any more but will be passed to the guest instead.
3209 Braille device. This will use BrlAPI to display the braille output on a real
3213 Three button serial mouse. Configure the guest to use Microsoft protocol.
3217 DEF("parallel
", HAS_ARG, QEMU_OPTION_parallel, \
3218 "-parallel dev redirect the parallel port to char device
'dev'\n",
3221 @item -parallel @var{dev}
3223 Redirect the virtual parallel port to host device @var{dev} (same
3224 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
3225 be used to use hardware devices connected on the corresponding host
3228 This option can be used several times to simulate up to 3 parallel
3231 Use @code{-parallel none} to disable all parallel ports.
3234 DEF("monitor
", HAS_ARG, QEMU_OPTION_monitor, \
3235 "-monitor dev redirect the monitor to char device
'dev'\n",
3238 @item -monitor @var{dev}
3240 Redirect the monitor to host device @var{dev} (same devices as the
3242 The default device is @code{vc} in graphical mode and @code{stdio} in
3244 Use @code{-monitor none} to disable the default monitor.
3246 DEF("qmp
", HAS_ARG, QEMU_OPTION_qmp, \
3247 "-qmp dev like
-monitor but opens
in 'control' mode
\n",
3250 @item -qmp @var{dev}
3252 Like -monitor but opens in 'control' mode.
3254 DEF("qmp
-pretty
", HAS_ARG, QEMU_OPTION_qmp_pretty, \
3255 "-qmp
-pretty dev like
-qmp but uses pretty JSON formatting
\n",
3258 @item -qmp-pretty @var{dev}
3260 Like -qmp but uses pretty JSON formatting.
3263 DEF("mon
", HAS_ARG, QEMU_OPTION_mon, \
3264 "-mon
[chardev
=]name
[,mode
=readline|control
]\n", QEMU_ARCH_ALL)
3266 @item -mon [chardev=]name[,mode=readline|control]
3268 Setup monitor on chardev @var{name}.
3271 DEF("debugcon
", HAS_ARG, QEMU_OPTION_debugcon, \
3272 "-debugcon dev redirect the debug console to char device
'dev'\n",
3275 @item -debugcon @var{dev}
3277 Redirect the debug console to host device @var{dev} (same devices as the
3278 serial port). The debug console is an I/O port which is typically port
3279 0xe9; writing to that I/O port sends output to this device.
3280 The default device is @code{vc} in graphical mode and @code{stdio} in
3284 DEF("pidfile
", HAS_ARG, QEMU_OPTION_pidfile, \
3285 "-pidfile file write PID to
'file'\n", QEMU_ARCH_ALL)
3287 @item -pidfile @var{file}
3289 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
3293 DEF("singlestep
", 0, QEMU_OPTION_singlestep, \
3294 "-singlestep always run
in singlestep mode
\n", QEMU_ARCH_ALL)
3298 Run the emulation in single step mode.
3301 DEF("S
", 0, QEMU_OPTION_S, \
3302 "-S freeze CPU at
startup (use
'c' to start execution
)\n",
3307 Do not start CPU at startup (you must type 'c' in the monitor).
3310 DEF("realtime
", HAS_ARG, QEMU_OPTION_realtime,
3311 "-realtime
[mlock
=on|off
]\n"
3312 " run qemu with realtime features
\n"
3313 " mlock
=on|off controls mlock
support (default: on
)\n",
3316 @item -realtime mlock=on|off
3318 Run qemu with realtime features.
3319 mlocking qemu and guest memory can be enabled via @option{mlock=on}
3320 (enabled by default).
3323 DEF("gdb
", HAS_ARG, QEMU_OPTION_gdb, \
3324 "-gdb dev wait
for gdb connection on
'dev'\n", QEMU_ARCH_ALL)
3326 @item -gdb @var{dev}
3328 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
3329 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
3330 stdio are reasonable use case. The latter is allowing to start QEMU from
3331 within gdb and establish the connection via a pipe:
3333 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
3337 DEF("s
", 0, QEMU_OPTION_s, \
3338 "-s shorthand
for -gdb tcp
::" DEFAULT_GDBSTUB_PORT "\n",
3343 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
3344 (@pxref{gdb_usage}).
3347 DEF("d
", HAS_ARG, QEMU_OPTION_d, \
3348 "-d item1
,... enable logging of specified
items (use
'-d help' for a list of log items
)\n",
3351 @item -d @var{item1}[,...]
3353 Enable logging of specified items. Use '-d help' for a list of log items.
3356 DEF("D
", HAS_ARG, QEMU_OPTION_D, \
3357 "-D logfile output log to
logfile (default stderr
)\n",
3360 @item -D @var{logfile}
3362 Output log in @var{logfile} instead of to stderr
3365 DEF("dfilter
", HAS_ARG, QEMU_OPTION_DFILTER, \
3366 "-dfilter range
,.. filter debug output to range of
addresses (useful
for -d cpu
,exec
,etc
..)\n",
3369 @item -dfilter @var{range1}[,...]
3371 Filter debug output to that relevant to a range of target addresses. The filter
3372 spec can be either @var{start}+@var{size}, @var{start}-@var{size} or
3373 @var{start}..@var{end} where @var{start} @var{end} and @var{size} are the
3374 addresses and sizes required. For example:
3376 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000
3378 Will dump output for any code in the 0x1000 sized block starting at 0x8000 and
3379 the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized
3380 block starting at 0xffffffc00005f000.
3383 DEF("L
", HAS_ARG, QEMU_OPTION_L, \
3384 "-L path set the directory
for the BIOS
, VGA BIOS and keymaps
\n",
3389 Set the directory for the BIOS, VGA BIOS and keymaps.
3391 To list all the data directories, use @code{-L help}.
3394 DEF("bios
", HAS_ARG, QEMU_OPTION_bios, \
3395 "-bios file set the filename
for the BIOS
\n", QEMU_ARCH_ALL)
3397 @item -bios @var{file}
3399 Set the filename for the BIOS.
3402 DEF("enable
-kvm
", 0, QEMU_OPTION_enable_kvm, \
3403 "-enable
-kvm enable KVM full virtualization support
\n", QEMU_ARCH_ALL)
3407 Enable KVM full virtualization support. This option is only available
3408 if KVM support is enabled when compiling.
3411 DEF("enable
-hax
", 0, QEMU_OPTION_enable_hax, \
3412 "-enable
-hax enable HAX virtualization support
\n", QEMU_ARCH_I386)
3416 Enable HAX (Hardware-based Acceleration eXecution) support. This option
3417 is only available if HAX support is enabled when compiling. HAX is only
3418 applicable to MAC and Windows platform, and thus does not conflict with
3422 DEF("xen
-domid
", HAS_ARG, QEMU_OPTION_xen_domid,
3423 "-xen
-domid id specify xen guest domain id
\n", QEMU_ARCH_ALL)
3424 DEF("xen
-create
", 0, QEMU_OPTION_xen_create,
3425 "-xen
-create create domain
using xen hypercalls
, bypassing xend
\n"
3426 " warning
: should not be used when xend is
in use
\n",
3428 DEF("xen
-attach
", 0, QEMU_OPTION_xen_attach,
3429 "-xen
-attach attach to existing xen domain
\n"
3430 " xend will use
this when starting QEMU
\n",
3432 DEF("xen
-domid
-restrict
", 0, QEMU_OPTION_xen_domid_restrict,
3433 "-xen
-domid
-restrict restrict set of available xen operations
\n"
3434 " to specified domain id
. (Does not affect
\n"
3435 " xenpv machine type
).\n",
3438 @item -xen-domid @var{id}
3440 Specify xen guest domain @var{id} (XEN only).
3443 Create domain using xen hypercalls, bypassing xend.
3444 Warning: should not be used when xend is in use (XEN only).
3447 Attach to existing xen domain.
3448 xend will use this when starting QEMU (XEN only).
3449 @findex -xen-domid-restrict
3450 Restrict set of available xen operations to specified domain id (XEN only).
3453 DEF("no
-reboot
", 0, QEMU_OPTION_no_reboot, \
3454 "-no
-reboot exit instead of rebooting
\n", QEMU_ARCH_ALL)
3458 Exit instead of rebooting.
3461 DEF("no
-shutdown
", 0, QEMU_OPTION_no_shutdown, \
3462 "-no
-shutdown stop before shutdown
\n", QEMU_ARCH_ALL)
3465 @findex -no-shutdown
3466 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
3467 This allows for instance switching to monitor to commit changes to the
3471 DEF("loadvm
", HAS_ARG, QEMU_OPTION_loadvm, \
3472 "-loadvm
[tag|id
]\n" \
3473 " start right away with a saved
state (loadvm
in monitor
)\n",
3476 @item -loadvm @var{file}
3478 Start right away with a saved state (@code{loadvm} in monitor)
3482 DEF("daemonize
", 0, QEMU_OPTION_daemonize, \
3483 "-daemonize daemonize QEMU after initializing
\n", QEMU_ARCH_ALL)
3488 Daemonize the QEMU process after initialization. QEMU will not detach from
3489 standard IO until it is ready to receive connections on any of its devices.
3490 This option is a useful way for external programs to launch QEMU without having
3491 to cope with initialization race conditions.
3494 DEF("option
-rom
", HAS_ARG, QEMU_OPTION_option_rom, \
3495 "-option
-rom rom load a file
, rom
, into the option ROM space
\n",
3498 @item -option-rom @var{file}
3500 Load the contents of @var{file} as an option ROM.
3501 This option is useful to load things like EtherBoot.
3504 HXCOMM Silently ignored for compatibility
3505 DEF("clock
", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL)
3507 HXCOMM Options deprecated by -rtc
3508 DEF("localtime
", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
3509 DEF("startdate
", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
3511 DEF("rtc
", HAS_ARG, QEMU_OPTION_rtc, \
3512 "-rtc
[base
=utc|localtime|date
][,clock
=host|rt|vm
][,driftfix
=none|slew
]\n" \
3513 " set the RTC base and clock
, enable drift fix
for clock
ticks (x86 only
)\n",
3518 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
3520 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
3521 UTC or local time, respectively. @code{localtime} is required for correct date in
3522 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
3523 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
3525 By default the RTC is driven by the host system time. This allows using of the
3526 RTC as accurate reference clock inside the guest, specifically if the host
3527 time is smoothly following an accurate external reference clock, e.g. via NTP.
3528 If you want to isolate the guest time from the host, you can set @option{clock}
3529 to @code{rt} instead. To even prevent it from progressing during suspension,
3530 you can set it to @code{vm}.
3532 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
3533 specifically with Windows' ACPI HAL. This option will try to figure out how
3534 many timer interrupts were not processed by the Windows guest and will
3538 DEF("icount
", HAS_ARG, QEMU_OPTION_icount, \
3539 "-icount
[shift
=N|auto
][,align
=on|off
][,sleep
=on|off
,rr
=record|replay
,rrfile
=<filename
>,rrsnapshot
=<snapshot
>]\n" \
3540 " enable virtual instruction counter with
2^N clock ticks per
\n" \
3541 " instruction
, enable aligning the host and virtual clocks
\n" \
3542 " or disable real time cpu sleeping
\n", QEMU_ARCH_ALL)
3544 @item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}]
3546 Enable virtual instruction counter. The virtual cpu will execute one
3547 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
3548 then the virtual cpu speed will be automatically adjusted to keep virtual
3549 time within a few seconds of real time.
3551 When the virtual cpu is sleeping, the virtual time will advance at default
3552 speed unless @option{sleep=on|off} is specified.
3553 With @option{sleep=on|off}, the virtual time will jump to the next timer deadline
3554 instantly whenever the virtual cpu goes to sleep mode and will not advance
3555 if no timer is enabled. This behavior give deterministic execution times from
3556 the guest point of view.
3558 Note that while this option can give deterministic behavior, it does not
3559 provide cycle accurate emulation. Modern CPUs contain superscalar out of
3560 order cores with complex cache hierarchies. The number of instructions
3561 executed often has little or no correlation with actual performance.
3563 @option{align=on} will activate the delay algorithm which will try
3564 to synchronise the host clock and the virtual clock. The goal is to
3565 have a guest running at the real frequency imposed by the shift option.
3566 Whenever the guest clock is behind the host clock and if
3567 @option{align=on} is specified then we print a message to the user
3568 to inform about the delay.
3569 Currently this option does not work when @option{shift} is @code{auto}.
3570 Note: The sync algorithm will work for those shift values for which
3571 the guest clock runs ahead of the host clock. Typically this happens
3572 when the shift value is high (how high depends on the host machine).
3574 When @option{rr} option is specified deterministic record/replay is enabled.
3575 Replay log is written into @var{filename} file in record mode and
3576 read from this file in replay mode.
3578 Option rrsnapshot is used to create new vm snapshot named @var{snapshot}
3579 at the start of execution recording. In replay mode this option is used
3580 to load the initial VM state.
3583 DEF("watchdog
", HAS_ARG, QEMU_OPTION_watchdog, \
3584 "-watchdog model
\n" \
3585 " enable virtual hardware watchdog
[default=none
]\n",
3588 @item -watchdog @var{model}
3590 Create a virtual hardware watchdog device. Once enabled (by a guest
3591 action), the watchdog must be periodically polled by an agent inside
3592 the guest or else the guest will be restarted. Choose a model for
3593 which your guest has drivers.
3595 The @var{model} is the model of hardware watchdog to emulate. Use
3596 @code{-watchdog help} to list available hardware models. Only one
3597 watchdog can be enabled for a guest.
3599 The following models may be available:
3602 iBASE 700 is a very simple ISA watchdog with a single timer.
3604 Intel 6300ESB I/O controller hub is a much more featureful PCI-based
3605 dual-timer watchdog.
3607 A virtual watchdog for s390x backed by the diagnose 288 hypercall
3608 (currently KVM only).
3612 DEF("watchdog
-action
", HAS_ARG, QEMU_OPTION_watchdog_action, \
3613 "-watchdog
-action reset|shutdown|poweroff|pause|debug|none
\n" \
3614 " action when watchdog fires
[default=reset
]\n",
3617 @item -watchdog-action @var{action}
3618 @findex -watchdog-action
3620 The @var{action} controls what QEMU will do when the watchdog timer
3623 @code{reset} (forcefully reset the guest).
3624 Other possible actions are:
3625 @code{shutdown} (attempt to gracefully shutdown the guest),
3626 @code{poweroff} (forcefully poweroff the guest),
3627 @code{pause} (pause the guest),
3628 @code{debug} (print a debug message and continue), or
3629 @code{none} (do nothing).
3631 Note that the @code{shutdown} action requires that the guest responds
3632 to ACPI signals, which it may not be able to do in the sort of
3633 situations where the watchdog would have expired, and thus
3634 @code{-watchdog-action shutdown} is not recommended for production use.
3639 @item -watchdog i6300esb -watchdog-action pause
3640 @itemx -watchdog ib700
3644 DEF("echr
", HAS_ARG, QEMU_OPTION_echr, \
3645 "-echr chr set terminal escape character instead of ctrl
-a
\n",
3649 @item -echr @var{numeric_ascii_value}
3651 Change the escape character used for switching to the monitor when using
3652 monitor and serial sharing. The default is @code{0x01} when using the
3653 @code{-nographic} option. @code{0x01} is equal to pressing
3654 @code{Control-a}. You can select a different character from the ascii
3655 control keys where 1 through 26 map to Control-a through Control-z. For
3656 instance you could use the either of the following to change the escape
3657 character to Control-t.
3664 DEF("virtioconsole
", HAS_ARG, QEMU_OPTION_virtiocon, \
3665 "-virtioconsole c
\n" \
3666 " set virtio console
\n", QEMU_ARCH_ALL)
3668 @item -virtioconsole @var{c}
3669 @findex -virtioconsole
3672 This option is maintained for backward compatibility.
3674 Please use @code{-device virtconsole} for the new way of invocation.
3677 DEF("show
-cursor
", 0, QEMU_OPTION_show_cursor, \
3678 "-show
-cursor show cursor
\n", QEMU_ARCH_ALL)
3681 @findex -show-cursor
3685 DEF("tb
-size
", HAS_ARG, QEMU_OPTION_tb_size, \
3686 "-tb
-size n set TB size
\n", QEMU_ARCH_ALL)
3688 @item -tb-size @var{n}
3693 DEF("incoming
", HAS_ARG, QEMU_OPTION_incoming, \
3694 "-incoming tcp
:[host
]:port
[,to
=maxport
][,ipv4
][,ipv6
]\n" \
3695 "-incoming rdma
:host
:port
[,ipv4
][,ipv6
]\n" \
3696 "-incoming unix
:socketpath
\n" \
3697 " prepare
for incoming migration
, listen on
\n" \
3698 " specified protocol and socket address
\n" \
3699 "-incoming fd
:fd
\n" \
3700 "-incoming exec
:cmdline
\n" \
3701 " accept incoming migration on given file descriptor
\n" \
3702 " or from given external command
\n" \
3703 "-incoming defer
\n" \
3704 " wait
for the URI to be specified via migrate_incoming
\n",
3707 @item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6]
3708 @itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6]
3710 Prepare for incoming migration, listen on a given tcp port.
3712 @item -incoming unix:@var{socketpath}
3713 Prepare for incoming migration, listen on a given unix socket.
3715 @item -incoming fd:@var{fd}
3716 Accept incoming migration from a given filedescriptor.
3718 @item -incoming exec:@var{cmdline}
3719 Accept incoming migration as an output from specified external command.
3721 @item -incoming defer
3722 Wait for the URI to be specified via migrate_incoming. The monitor can
3723 be used to change settings (such as migration parameters) prior to issuing
3724 the migrate_incoming to allow the migration to begin.
3727 DEF("only
-migratable
", 0, QEMU_OPTION_only_migratable, \
3728 "-only
-migratable allow only migratable devices
\n", QEMU_ARCH_ALL)
3730 @item -only-migratable
3731 @findex -only-migratable
3732 Only allow migratable devices. Devices will not be allowed to enter an
3736 DEF("nodefaults
", 0, QEMU_OPTION_nodefaults, \
3737 "-nodefaults don
't create default devices\n", QEMU_ARCH_ALL)
3741 Don't create
default devices
. Normally
, QEMU sets the
default devices like serial
3742 port
, parallel port
, virtual console
, monitor device
, VGA adapter
, floppy and
3743 CD
-ROM drive and others
. The @code
{-nodefaults
} option will disable all those
3748 DEF("chroot", HAS_ARG
, QEMU_OPTION_chroot
, \
3749 "-chroot dir chroot to dir just before starting the VM\n",
3753 @item
-chroot @
var{dir
}
3755 Immediately before starting guest execution
, chroot to the specified
3756 directory
. Especially useful
in combination with
-runas
.
3760 DEF("runas", HAS_ARG
, QEMU_OPTION_runas
, \
3761 "-runas user change to user id user just before starting the VM\n",
3765 @item
-runas @
var{user
}
3767 Immediately before starting guest execution
, drop root privileges
, switching
3768 to the specified user
.
3771 DEF("prom-env", HAS_ARG
, QEMU_OPTION_prom_env
,
3772 "-prom-env variable=value\n"
3773 " set OpenBIOS nvram variables\n",
3774 QEMU_ARCH_PPC | QEMU_ARCH_SPARC
)
3776 @item
-prom
-env @
var{variable
}=@
var{value
}
3778 Set OpenBIOS nvram @
var{variable
} to given @
var{value
} (PPC
, SPARC only
).
3780 DEF("semihosting", 0, QEMU_OPTION_semihosting
,
3781 "-semihosting semihosting mode\n",
3782 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3786 @findex
-semihosting
3787 Enable semihosting
mode (ARM
, M68K
, Xtensa
, MIPS only
).
3789 DEF("semihosting-config", HAS_ARG
, QEMU_OPTION_semihosting_config
,
3790 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \
3791 " semihosting configuration\n",
3792 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3795 @item
-semihosting
-config
[enable
=on|off
][,target
=native|gdb|auto
][,arg
=str
[,...]]
3796 @findex
-semihosting
-config
3797 Enable and configure
semihosting (ARM
, M68K
, Xtensa
, MIPS only
).
3799 @item target
=@code
{native|gdb|auto
}
3800 Defines where the semihosting calls will be addressed
, to
QEMU (@code
{native
})
3801 or to
GDB (@code
{gdb
}). The
default is @code
{auto
}, which means @code
{gdb
}
3802 during debug sessions and @code
{native
} otherwise
.
3803 @item arg
=@
var{str1
},arg
=@
var{str2
},...
3804 Allows the user to pass input arguments
, and can be used multiple times to build
3805 up a list
. The old
-style @code
{-kernel
}/@code
{-append
} method of passing a
3806 command line is still supported
for backward compatibility
. If both the
3807 @code
{--semihosting
-config arg
} and the @code
{-kernel
}/@code
{-append
} are
3808 specified
, the former is passed to semihosting as it always takes precedence
.
3811 DEF("old-param", 0, QEMU_OPTION_old_param
,
3812 "-old-param old param mode\n", QEMU_ARCH_ARM
)
3815 @findex
-old
-param (ARM
)
3816 Old param
mode (ARM only
).
3819 DEF("sandbox", HAS_ARG
, QEMU_OPTION_sandbox
, \
3820 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n",
3823 @item
-sandbox @
var{arg
}
3825 Enable Seccomp mode
2 system call filter
. 'on' will enable syscall filtering and
'off' will
3826 disable it
. The
default is
'off'.
3829 DEF("readconfig", HAS_ARG
, QEMU_OPTION_readconfig
,
3830 "-readconfig <file>\n", QEMU_ARCH_ALL
)
3832 @item
-readconfig @
var{file
}
3834 Read device configuration from @
var{file
}. This approach is useful when you want to spawn
3835 QEMU process with many command line options but you don
't want to exceed the command line
3838 DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
3839 "-writeconfig <file>\n"
3840 " read/write config file\n", QEMU_ARCH_ALL)
3842 @item -writeconfig @var{file}
3843 @findex -writeconfig
3844 Write device configuration to @var{file}. The @var{file} can be either filename to save
3845 command line and device configuration into file or dash @code{-}) character to print the
3846 output to stdout. This can be later used as input file for @code{-readconfig} option.
3848 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig,
3850 " do not load default config files at startup\n",
3854 @findex -nodefconfig
3855 Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
3856 The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
3858 DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
3860 " do not load user-provided config files at startup\n",
3863 @item -no-user-config
3864 @findex -no-user-config
3865 The @code{-no-user-config} option makes QEMU not load any of the user-provided
3866 config files on @var{sysconfdir}, but won't make it skip the QEMU
-provided config
3867 files from @
var{datadir
}.
3869 DEF("trace", HAS_ARG
, QEMU_OPTION_trace
,
3870 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
3871 " specify tracing options\n",
3874 HXCOMM This line is not accurate
, as some sub
-options are backend
-specific but
3875 HXCOMM HX does not support conditional compilation of text
.
3876 @item
-trace [[enable
=]@
var{pattern
}][,events
=@
var{file
}][,file
=@
var{file
}]
3878 @include qemu
-option
-trace.texi
3882 DEF("qtest", HAS_ARG
, QEMU_OPTION_qtest
, "", QEMU_ARCH_ALL
)
3883 DEF("qtest-log", HAS_ARG
, QEMU_OPTION_qtest_log
, "", QEMU_ARCH_ALL
)
3886 DEF("enable-fips", 0, QEMU_OPTION_enablefips
,
3887 "-enable-fips enable FIPS 140-2 compliance\n",
3892 @findex
-enable
-fips
3893 Enable FIPS
140-2 compliance mode
.
3896 HXCOMM Deprecated by
-machine accel
=tcg property
3897 DEF("no-kvm", 0, QEMU_OPTION_no_kvm
, "", QEMU_ARCH_I386
)
3899 HXCOMM Deprecated by kvm
-pit driver properties
3900 DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection
,
3903 HXCOMM
Deprecated (ignored
)
3904 DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit
, "", QEMU_ARCH_I386
)
3906 HXCOMM Deprecated by
-machine kernel_irqchip
=on|off property
3907 DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip
, "", QEMU_ARCH_I386
)
3909 HXCOMM
Deprecated (ignored
)
3910 DEF("tdf", 0, QEMU_OPTION_tdf
,"", QEMU_ARCH_ALL
)
3912 DEF("msg", HAS_ARG
, QEMU_OPTION_msg
,
3913 "-msg timestamp[=on|off]\n"
3914 " change the format of messages\n"
3915 " on|off controls leading timestamps (default:on)\n",
3918 @item
-msg timestamp
[=on|off
]
3920 prepend a timestamp to each log message
.(default:on
)
3923 DEF("dump-vmstate", HAS_ARG
, QEMU_OPTION_dump_vmstate
,
3924 "-dump-vmstate <file>\n"
3925 " Output vmstate information in JSON format to file.\n"
3926 " Use the scripts/vmstate-static-checker.py file to\n"
3927 " check for possible regressions in migration code\n"
3928 " by comparing two such vmstate dumps.\n",
3931 @item
-dump
-vmstate @
var{file
}
3932 @findex
-dump
-vmstate
3933 Dump json
-encoded vmstate information
for current machine type to file
3941 DEFHEADING(Generic object creation
)
3946 DEF("object", HAS_ARG
, QEMU_OPTION_object
,
3947 "-object TYPENAME[,PROP1=VALUE1,...]\n"
3948 " create a new object of type TYPENAME setting properties\n"
3949 " in the order they are specified. Note that the 'id'\n"
3950 " property must be set. These objects are placed in the\n"
3951 " '/objects' path.\n",
3954 @item
-object @
var{typename
}[,@
var{prop1
}=@
var{value1
},...]
3956 Create a
new object of type @
var{typename
} setting properties
3957 in the order they are specified
. Note that the
'id'
3958 property must be set
. These objects are placed
in the
3963 @item
-object memory
-backend
-file
,id
=@
var{id
},size
=@
var{size
},mem
-path
=@
var{dir
},share
=@
var{on|off
}
3965 Creates a memory file backend object
, which can be used to back
3966 the guest RAM with huge pages
. The @option
{id
} parameter is a
3967 unique ID that will be used to reference
this memory region
3968 when configuring the @option
{-numa
} argument
. The @option
{size
}
3969 option provides the size of the memory region
, and accepts
3970 common suffixes
, eg @option
{500M
}. The @option
{mem
-path
} provides
3971 the path to either a shared memory or huge page filesystem mount
.
3972 The @option
{share
} boolean option determines whether the memory
3973 region is marked as
private to QEMU
, or shared
. The latter allows
3974 a co
-operating external process to access the QEMU memory region
.
3976 @item
-object rng
-random
,id
=@
var{id
},filename
=@
var{/dev
/random
}
3978 Creates a random number generator backend which obtains entropy from
3979 a device on the host
. The @option
{id
} parameter is a unique ID that
3980 will be used to reference
this entropy backend from the @option
{virtio
-rng
}
3981 device
. The @option
{filename
} parameter specifies which file to obtain
3982 entropy from and
if omitted defaults to @option
{/dev
/random
}.
3984 @item
-object rng
-egd
,id
=@
var{id
},chardev
=@
var{chardevid
}
3986 Creates a random number generator backend which obtains entropy from
3987 an external daemon running on the host
. The @option
{id
} parameter is
3988 a unique ID that will be used to reference
this entropy backend from
3989 the @option
{virtio
-rng
} device
. The @option
{chardev
} parameter is
3990 the unique ID of a character device backend that provides the connection
3993 @item
-object tls
-creds
-anon
,id
=@
var{id
},endpoint
=@
var{endpoint
},dir
=@
var{/path
/to
/cred
/dir
},verify
-peer
=@
var{on|off
}
3995 Creates a TLS anonymous credentials object
, which can be used to provide
3996 TLS support on network backends
. The @option
{id
} parameter is a unique
3997 ID which network backends will use to access the credentials
. The
3998 @option
{endpoint
} is either @option
{server
} or @option
{client
} depending
3999 on whether the QEMU network backend that uses the credentials will be
4000 acting as a client or as a server
. If @option
{verify
-peer
} is enabled
4001 (the
default) then once the handshake is completed
, the peer credentials
4002 will be verified
, though
this is a no
-op
for anonymous credentials
.
4004 The @
var{dir
} parameter tells QEMU where to find the credential
4005 files
. For server endpoints
, this directory may contain a file
4006 @
var{dh
-params
.pem
} providing diffie
-hellman parameters to use
4007 for the TLS server
. If the file is missing
, QEMU will generate
4008 a set of DH parameters at startup
. This is a computationally
4009 expensive operation that consumes random pool entropy
, so it is
4010 recommended that a persistent set of parameters be generated
4013 @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
}
4015 Creates a TLS anonymous credentials object
, which can be used to provide
4016 TLS support on network backends
. The @option
{id
} parameter is a unique
4017 ID which network backends will use to access the credentials
. The
4018 @option
{endpoint
} is either @option
{server
} or @option
{client
} depending
4019 on whether the QEMU network backend that uses the credentials will be
4020 acting as a client or as a server
. If @option
{verify
-peer
} is enabled
4021 (the
default) then once the handshake is completed
, the peer credentials
4022 will be verified
. With x509 certificates
, this implies that the clients
4023 must be provided with valid client certificates too
.
4025 The @
var{dir
} parameter tells QEMU where to find the credential
4026 files
. For server endpoints
, this directory may contain a file
4027 @
var{dh
-params
.pem
} providing diffie
-hellman parameters to use
4028 for the TLS server
. If the file is missing
, QEMU will generate
4029 a set of DH parameters at startup
. This is a computationally
4030 expensive operation that consumes random pool entropy
, so it is
4031 recommended that a persistent set of parameters be generated
4034 For x509 certificate credentials the directory will contain further files
4035 providing the x509 certificates
. The certificates must be stored
4036 in PEM format
, in filenames @
var{ca
-cert
.pem
}, @
var{ca
-crl
.pem
} (optional
),
4037 @
var{server
-cert
.pem
} (only servers
), @
var{server
-key
.pem
} (only servers
),
4038 @
var{client
-cert
.pem
} (only clients
), and @
var{client
-key
.pem
} (only clients
).
4040 For the @
var{server
-key
.pem
} and @
var{client
-key
.pem
} files which
4041 contain sensitive
private keys
, it is possible to use an encrypted
4042 version by providing the @
var{passwordid
} parameter
. This provides
4043 the ID of a previously created @code
{secret
} object containing the
4044 password
for decryption
.
4046 @item
-object filter
-buffer
,id
=@
var{id
},netdev
=@
var{netdevid
},interval
=@
var{t
}[,queue
=@
var{all|rx|tx
}][,status
=@
var{on|off
}]
4048 Interval @
var{t
} can
't be 0, this filter batches the packet delivery: all
4049 packets arriving in a given interval on netdev @var{netdevid} are delayed
4050 until the end of the interval. Interval is in microseconds.
4051 @option{status} is optional that indicate whether the netfilter is
4052 on (enabled) or off (disabled), the default status for netfilter will be 'on
'.
4054 queue @var{all|rx|tx} is an option that can be applied to any netfilter.
4056 @option{all}: the filter is attached both to the receive and the transmit
4057 queue of the netdev (default).
4059 @option{rx}: the filter is attached to the receive queue of the netdev,
4060 where it will receive packets sent to the netdev.
4062 @option{tx}: the filter is attached to the transmit queue of the netdev,
4063 where it will receive packets sent by the netdev.
4065 @item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid}[,queue=@var{all|rx|tx}]
4067 filter-mirror on netdev @var{netdevid},mirror net packet to chardev
4070 @item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},
4071 outdev=@var{chardevid}[,queue=@var{all|rx|tx}]
4073 filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev
4074 @
var{chardevid
},and redirect indev
's packet to filter.
4075 Create a filter-redirector we need to differ outdev id from indev id, id can not
4076 be the same. we can just use indev or outdev, but at least one of indev or outdev
4077 need to be specified.
4079 @item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},rewriter-mode=@var{mode}[,queue=@var{all|rx|tx}]
4081 Filter-rewriter is a part of COLO project.It will rewrite tcp packet to
4082 secondary from primary to keep secondary tcp connection,and rewrite
4083 tcp packet to primary from secondary make tcp packet can be handled by
4088 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4089 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4090 -object filter-rewriter,id=rew0,netdev=hn0,queue=all
4092 @item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}]
4094 Dump the network traffic on netdev @var{dev} to the file specified by
4095 @var{filename}. At most @var{len} bytes (64k by default) per packet are stored.
4096 The file format is libpcap, so it can be analyzed with tools such as tcpdump
4099 @item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},
4100 outdev=@var{chardevid}
4102 Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with
4103 secondary packet. If the packets are same, we will output primary
4104 packet to outdev@var{chardevid}, else we will notify colo-frame
4105 do checkpoint and send primary packet to outdev@var{chardevid}.
4107 we must use it with the help of filter-mirror and filter-redirector.
4112 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown
4113 -device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66
4114 -chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait
4115 -chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait
4116 -chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait
4117 -chardev socket,id=compare0-0,host=3.3.3.3,port=9001
4118 -chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait
4119 -chardev socket,id=compare_out0,host=3.3.3.3,port=9005
4120 -object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0
4121 -object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out
4122 -object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0
4123 -object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0
4126 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown
4127 -device e1000,netdev=hn0,mac=52:a4:00:12:78:66
4128 -chardev socket,id=red0,host=3.3.3.3,port=9003
4129 -chardev socket,id=red1,host=3.3.3.3,port=9004
4130 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4131 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4135 If you want to know the detail of above command line, you can read
4136 the colo-compare git log.
4138 @item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}]
4140 Creates a cryptodev backend which executes crypto opreation from
4141 the QEMU cipher APIS. The @var{id} parameter is
4142 a unique ID that will be used to reference this cryptodev backend from
4143 the @option{virtio-crypto} device. The @var{queues} parameter is optional,
4144 which specify the queue number of cryptodev backend, the default of
4149 # qemu-system-x86_64 \
4151 -object cryptodev-backend-builtin,id=cryptodev0 \
4152 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4156 @item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4157 @item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4159 Defines a secret to store a password, encryption key, or some other sensitive
4160 data. The sensitive data can either be passed directly via the @var{data}
4161 parameter, or indirectly via the @var{file} parameter. Using the @var{data}
4162 parameter is insecure unless the sensitive data is encrypted.
4164 The sensitive data can be provided in raw format (the default), or base64.
4165 When encoded as JSON, the raw format only supports valid UTF-8 characters,
4166 so base64 is recommended for sending binary data. QEMU will convert from
4167 which ever format is provided to the format it needs internally. eg, an
4168 RBD password can be provided in raw format, even though it will be base64
4169 encoded when passed onto the RBD sever.
4171 For added protection, it is possible to encrypt the data associated with
4172 a secret using the AES-256-CBC cipher. Use of encryption is indicated
4173 by providing the @var{keyid} and @var{iv} parameters. The @var{keyid}
4174 parameter provides the ID of a previously defined secret that contains
4175 the AES-256 decryption key. This key should be 32-bytes long and be
4176 base64 encoded. The @var{iv} parameter provides the random initialization
4177 vector used for encryption of this particular secret and should be a
4178 base64 encrypted string of the 16-byte IV.
4180 The simplest (insecure) usage is to provide the secret inline
4184 # $QEMU -object secret,id=sec0,data=letmein,format=raw
4188 The simplest secure usage is to provide the secret via a file
4190 # echo -n "letmein" > mypasswd.txt
4191 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw
4193 For greater security, AES-256-CBC should be used. To illustrate usage,
4194 consider the openssl command line tool which can encrypt the data. Note
4195 that when encrypting, the plaintext must be padded to the cipher block
4196 size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm.
4198 First a master key needs to be created in base64 encoding:
4201 # openssl rand -base64 32 > key.b64
4202 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"')
4205 Each secret to be encrypted needs to have a random initialization vector
4206 generated. These do not need to be kept secret
4209 # openssl rand -base64 16 > iv.b64
4210 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"')
4213 The secret to be defined can now be encrypted, in this case we're
4214 telling openssl to base64 encode the result
, but it could be left
4215 as raw bytes
if desired
.
4218 # SECRET
=$
(echo
-n
"letmein" |
4219 openssl enc
-aes
-256-cbc
-a
-K $KEY
-iv $IV
)
4222 When launching QEMU
, create a master secret pointing to @code
{key
.b64
}
4223 and specify that to be used to decrypt the user password
. Pass the
4224 contents of @code
{iv
.b64
} to the second secret
4228 -object secret
,id
=secmaster0
,format
=base64
,file
=key
.b64 \
4229 -object secret
,id
=sec0
,keyid
=secmaster0
,format
=base64
,\
4230 data
=$SECRET
,iv
=$
(<iv
.b64
)
4238 HXCOMM This is the last statement
. Insert
new options before
this line
!