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)\n", 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-hd.physical_block_size=4096 disk-image.img
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 @item -blockdev @var{option}[,@var{option}[,@var{option}[,...]]]
617 Define a new block driver node. Some of the options apply to all block drivers,
618 other options are only accepted for a specific block driver. See below for a
619 list of generic options and options for the most common block drivers.
621 Options that expect a reference to another node (e.g. @code{file}) can be
622 given in two ways. Either you specify the node name of an already existing node
623 (file=@var{node-name}), or you define a new node inline, adding options
624 for the referenced node after a dot (file.filename=@var{path},file.aio=native).
626 A block driver node created with @option{-blockdev} can be used for a guest
627 device by specifying its node name for the @code{drive} property in a
628 @option{-device} argument that defines a block device.
631 @item Valid options for any block driver node:
635 Specifies the block driver to use for the given node.
637 This defines the name of the block driver node by which it will be referenced
638 later. The name must be unique, i.e. it must not match the name of a different
639 block driver node, or (if you use @option{-drive} as well) the ID of a drive.
641 If no node name is specified, it is automatically generated. The generated node
642 name is not intended to be predictable and changes between QEMU invocations.
643 For the top level, an explicit node name must be specified.
645 Open the node read-only. Guest write attempts will fail.
647 The host page cache can be avoided with @option{cache.direct=on}. This will
648 attempt to do disk IO directly to the guest's memory. QEMU may still perform an
649 internal copy of the data.
651 In case you don't care about data integrity over host failures, you can use
652 @option{cache.no-flush=on}. This option tells QEMU that it never needs to write
653 any data to the disk but can instead keep things in cache. If anything goes
654 wrong, like your host losing power, the disk storage getting disconnected
655 accidentally, etc. your image will most probably be rendered unusable.
656 @item discard=@var{discard}
657 @var{discard} is one of "ignore
" (or "off
") or "unmap
" (or "on
") and controls
658 whether @code{discard} (also known as @code{trim} or @code{unmap}) requests are
659 ignored or passed to the filesystem. Some machine types may not support
661 @item detect-zeroes=@var{detect-zeroes}
662 @var{detect-zeroes} is "off
", "on
" or "unmap
" and enables the automatic
663 conversion of plain zero writes by the OS to driver specific optimized
664 zero write commands. You may even choose "unmap
" if @var{discard} is set
665 to "unmap
" to allow a zero write to be converted to an @code{unmap} operation.
668 @item Driver-specific options for @code{file}
670 This is the protocol-level block driver for accessing regular files.
674 The path to the image file in the local filesystem
676 Specifies the AIO backend (threads/native, default: threads)
680 -blockdev driver=file,node-name=disk,filename=disk.img
683 @item Driver-specific options for @code{raw}
685 This is the image format block driver for raw images. It is usually
686 stacked on top of a protocol level block driver such as @code{file}.
690 Reference to or definition of the data source block driver node
691 (e.g. a @code{file} driver node)
695 -blockdev driver=file,node-name=disk_file,filename=disk.img
696 -blockdev driver=raw,node-name=disk,file=disk_file
700 -blockdev driver=raw,node-name=disk,file.driver=file,file.filename=disk.img
703 @item Driver-specific options for @code{qcow2}
705 This is the image format block driver for qcow2 images. It is usually
706 stacked on top of a protocol level block driver such as @code{file}.
710 Reference to or definition of the data source block driver node
711 (e.g. a @code{file} driver node)
714 Reference to or definition of the backing file block device (default is taken
715 from the image file). It is allowed to pass an empty string here in order to
716 disable the default backing file.
719 Whether to enable the lazy refcounts feature (on/off; default is taken from the
723 The maximum total size of the L2 table and refcount block caches in bytes
724 (default: 1048576 bytes or 8 clusters, whichever is larger)
727 The maximum size of the L2 table cache in bytes
728 (default: 4/5 of the total cache size)
730 @item refcount-cache-size
731 The maximum size of the refcount block cache in bytes
732 (default: 1/5 of the total cache size)
734 @item cache-clean-interval
735 Clean unused entries in the L2 and refcount caches. The interval is in seconds.
736 The default value is 0 and it disables this feature.
738 @item pass-discard-request
739 Whether discard requests to the qcow2 device should be forwarded to the data
740 source (on/off; default: on if discard=unmap is specified, off otherwise)
742 @item pass-discard-snapshot
743 Whether discard requests for the data source should be issued when a snapshot
744 operation (e.g. deleting a snapshot) frees clusters in the qcow2 file (on/off;
747 @item pass-discard-other
748 Whether discard requests for the data source should be issued on other
749 occasions where a cluster gets freed (on/off; default: off)
752 Which overlap checks to perform for writes to the image
753 (none/constant/cached/all; default: cached). For details or finer
754 granularity control refer to the QAPI documentation of @code{blockdev-add}.
759 -blockdev driver=file,node-name=my_file,filename=/tmp/disk.qcow2
760 -blockdev driver=qcow2,node-name=hda,file=my_file,overlap-check=none,cache-size=16777216
764 -blockdev driver=qcow2,node-name=disk,file.driver=http,file.filename=http://example.com/image.qcow2
767 @item Driver-specific options for other drivers
768 Please refer to the QAPI documentation of the @code{blockdev-add} QMP command.
774 DEF("drive
", HAS_ARG, QEMU_OPTION_drive,
775 "-drive
[file
=file
][,if=type
][,bus
=n
][,unit
=m
][,media
=d
][,index
=i
]\n"
776 " [,cyls
=c
,heads
=h
,secs
=s
[,trans
=t
]][,snapshot
=on|off
]\n"
777 " [,cache
=writethrough|writeback|none|directsync|unsafe
][,format
=f
]\n"
778 " [,serial
=s
][,addr
=A
][,rerror
=ignore|stop|report
]\n"
779 " [,werror
=ignore|stop|report|enospc
][,id
=name
][,aio
=threads|native
]\n"
780 " [,readonly
=on|off
][,copy
-on
-read
=on|off
]\n"
781 " [,discard
=ignore|unmap
][,detect
-zeroes
=on|off|unmap
]\n"
782 " [[,bps
=b
]|
[[,bps_rd
=r
][,bps_wr
=w
]]]\n"
783 " [[,iops
=i
]|
[[,iops_rd
=r
][,iops_wr
=w
]]]\n"
784 " [[,bps_max
=bm
]|
[[,bps_rd_max
=rm
][,bps_wr_max
=wm
]]]\n"
785 " [[,iops_max
=im
]|
[[,iops_rd_max
=irm
][,iops_wr_max
=iwm
]]]\n"
786 " [[,iops_size
=is
]]\n"
788 " use
'file' as a drive image
\n", QEMU_ARCH_ALL)
790 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
793 Define a new drive. This includes creating a block driver node (the backend) as
794 well as a guest device, and is mostly a shortcut for defining the corresponding
795 @option{-blockdev} and @option{-device} options.
797 @option{-drive} accepts all options that are accepted by @option{-blockdev}. In
798 addition, it knows the following options:
801 @item file=@var{file}
802 This option defines which disk image (@pxref{disk_images}) to use with
803 this drive. If the filename contains comma, you must double it
804 (for instance, "file
=my
,,file
" to use file "my
,file
").
806 Special files such as iSCSI devices can be specified using protocol
807 specific URLs. See the section for "Device URL Syntax
" for more information.
808 @item if=@var{interface}
809 This option defines on which type on interface the drive is connected.
810 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio, none.
811 @item bus=@var{bus},unit=@var{unit}
812 These options define where is connected the drive by defining the bus number and
814 @item index=@var{index}
815 This option defines where is connected the drive by using an index in the list
816 of available connectors of a given interface type.
817 @item media=@var{media}
818 This option defines the type of the media: disk or cdrom.
819 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
820 These options have the same definition as they have in @option{-hdachs}.
821 @item snapshot=@var{snapshot}
822 @var{snapshot} is "on
" or "off
" and controls snapshot mode for the given drive
823 (see @option{-snapshot}).
824 @item cache=@var{cache}
825 @var{cache} is "none
", "writeback
", "unsafe
", "directsync
" or "writethrough
"
826 and controls how the host cache is used to access block data. This is a
827 shortcut that sets the @option{cache.direct} and @option{cache.no-flush}
828 options (as in @option{-blockdev}), and additionally @option{cache.writeback},
829 which provides a default for the @option{write-cache} option of block guest
830 devices (as in @option{-device}). The modes correspond to the following
833 @c Our texi2pod.pl script doesn't support @multitable, so fall back to using
834 @c plain ASCII art (well, UTF-8 art really). This looks okay both in the manpage
835 @c and the HTML output.
837 @ │ cache.writeback cache.direct cache.no-flush
838 ─────────────┼─────────────────────────────────────────────────
839 writeback │ on off off
841 writethrough │ off off off
842 directsync │ off on off
846 The default mode is @option{cache=writeback}.
849 @var{aio} is "threads
", or "native
" and selects between pthread based disk I/O and native Linux AIO.
850 @item format=@var{format}
851 Specify which disk @var{format} will be used rather than detecting
852 the format. Can be used to specify format=raw to avoid interpreting
853 an untrusted format header.
854 @item serial=@var{serial}
855 This option specifies the serial number to assign to the device.
856 @item addr=@var{addr}
857 Specify the controller's PCI address (if=virtio only).
858 @item werror=@var{action},rerror=@var{action}
859 Specify which @var{action} to take on write and read errors. Valid actions are:
860 "ignore
" (ignore the error and try to continue), "stop
" (pause QEMU),
861 "report
" (report the error to the guest), "enospc
" (pause QEMU only if the
862 host disk is full; report the error to the guest otherwise).
863 The default setting is @option{werror=enospc} and @option{rerror=report}.
864 @item copy-on-read=@var{copy-on-read}
865 @var{copy-on-read} is "on
" or "off
" and enables whether to copy read backing
866 file sectors into the image file.
867 @item bps=@var{b},bps_rd=@var{r},bps_wr=@var{w}
868 Specify bandwidth throttling limits in bytes per second, either for all request
869 types or for reads or writes only. Small values can lead to timeouts or hangs
870 inside the guest. A safe minimum for disks is 2 MB/s.
871 @item bps_max=@var{bm},bps_rd_max=@var{rm},bps_wr_max=@var{wm}
872 Specify bursts in bytes per second, either for all request types or for reads
873 or writes only. Bursts allow the guest I/O to spike above the limit
875 @item iops=@var{i},iops_rd=@var{r},iops_wr=@var{w}
876 Specify request rate limits in requests per second, either for all request
877 types or for reads or writes only.
878 @item iops_max=@var{bm},iops_rd_max=@var{rm},iops_wr_max=@var{wm}
879 Specify bursts in requests per second, either for all request types or for reads
880 or writes only. Bursts allow the guest I/O to spike above the limit
882 @item iops_size=@var{is}
883 Let every @var{is} bytes of a request count as a new request for iops
884 throttling purposes. Use this option to prevent guests from circumventing iops
885 limits by sending fewer but larger requests.
887 Join a throttling quota group with given name @var{g}. All drives that are
888 members of the same group are accounted for together. Use this option to
889 prevent guests from circumventing throttling limits by using many small disks
890 instead of a single larger disk.
893 By default, the @option{cache.writeback=on} mode is used. It will report data
894 writes as completed as soon as the data is present in the host page cache.
895 This is safe as long as your guest OS makes sure to correctly flush disk caches
896 where needed. If your guest OS does not handle volatile disk write caches
897 correctly and your host crashes or loses power, then the guest may experience
900 For such guests, you should consider using @option{cache.writeback=off}. This
901 means that the host page cache will be used to read and write data, but write
902 notification will be sent to the guest only after QEMU has made sure to flush
903 each write to the disk. Be aware that this has a major impact on performance.
905 When using the @option{-snapshot} option, unsafe caching is always used.
907 Copy-on-read avoids accessing the same backing file sectors repeatedly and is
908 useful when the backing file is over a slow network. By default copy-on-read
911 Instead of @option{-cdrom} you can use:
913 qemu-system-i386 -drive file=file,index=2,media=cdrom
916 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
919 qemu-system-i386 -drive file=file,index=0,media=disk
920 qemu-system-i386 -drive file=file,index=1,media=disk
921 qemu-system-i386 -drive file=file,index=2,media=disk
922 qemu-system-i386 -drive file=file,index=3,media=disk
925 You can open an image using pre-opened file descriptors from an fd set:
928 -add-fd fd=3,set=2,opaque="rdwr
:/path
/to
/file
"
929 -add-fd fd=4,set=2,opaque="rdonly
:/path
/to
/file
"
930 -drive file=/dev/fdset/2,index=0,media=disk
933 You can connect a CDROM to the slave of ide0:
935 qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
938 If you don't specify the "file
=" argument, you define an empty drive:
940 qemu-system-i386 -drive if=ide,index=1,media=cdrom
943 Instead of @option{-fda}, @option{-fdb}, you can use:
945 qemu-system-i386 -drive file=file,index=0,if=floppy
946 qemu-system-i386 -drive file=file,index=1,if=floppy
949 By default, @var{interface} is "ide
" and @var{index} is automatically
952 qemu-system-i386 -drive file=a -drive file=b"
956 qemu
-system
-i386
-hda a
-hdb b
960 DEF("mtdblock", HAS_ARG
, QEMU_OPTION_mtdblock
,
961 "-mtdblock file use 'file' as on-board Flash memory image\n",
964 @item
-mtdblock @
var{file
}
966 Use @
var{file
} as on
-board Flash memory image
.
969 DEF("sd", HAS_ARG
, QEMU_OPTION_sd
,
970 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL
)
974 Use @
var{file
} as SecureDigital card image
.
977 DEF("pflash", HAS_ARG
, QEMU_OPTION_pflash
,
978 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL
)
980 @item
-pflash @
var{file
}
982 Use @
var{file
} as a parallel flash image
.
985 DEF("snapshot", 0, QEMU_OPTION_snapshot
,
986 "-snapshot write to temporary files instead of disk image files\n",
991 Write to temporary files instead of disk image files
. In
this case,
992 the raw disk image you use is not written back
. You can however force
993 the write back by pressing @key
{C
-a s
} (@pxref
{disk_images
}).
996 DEF("hdachs", HAS_ARG
, QEMU_OPTION_hdachs
, \
997 "-hdachs c,h,s[,t]\n" \
998 " force hard disk 0 physical geometry and the optional BIOS\n" \
999 " translation (t=none or lba) (usually QEMU can guess them)\n",
1002 @item
-hdachs @
var{c
},@
var{h
},@
var{s
},[,@
var{t
}]
1004 Force hard disk
0 physical
geometry (1 <= @
var{c
} <= 16383, 1 <=
1005 @
var{h
} <= 16, 1 <= @
var{s
} <= 63) and optionally force the BIOS
1006 translation
mode (@
var{t
}=none
, lba or auto
). Usually QEMU can guess
1007 all those parameters
. This option is deprecated
, please use
1008 @code
{-device ide
-hd
,cyls
=c
,heads
=h
,secs
=s
,...} instead
.
1011 DEF("fsdev", HAS_ARG
, QEMU_OPTION_fsdev
,
1012 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
1013 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n"
1014 " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n"
1015 " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n"
1016 " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n"
1017 " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n"
1018 " [[,throttling.iops-size=is]]\n",
1023 @item
-fsdev @
var{fsdriver
},id
=@
var{id
},path
=@
var{path
},[security_model
=@
var{security_model
}][,writeout
=@
var{writeout
}][,readonly
][,socket
=@
var{socket
}|sock_fd
=@
var{sock_fd
}][,fmode
=@
var{fmode
}][,dmode
=@
var{dmode
}]
1025 Define a
new file system device
. Valid options are
:
1027 @item @
var{fsdriver
}
1028 This option specifies the fs driver backend to use
.
1029 Currently
"local", "handle" and
"proxy" file system drivers are supported
.
1031 Specifies identifier
for this device
1032 @item path
=@
var{path
}
1033 Specifies the export path
for the file system device
. Files under
1034 this path will be available to the
9p client on the guest
.
1035 @item security_model
=@
var{security_model
}
1036 Specifies the security model to be used
for this export path
.
1037 Supported security models are
"passthrough", "mapped-xattr", "mapped-file" and
"none".
1038 In
"passthrough" security model
, files are stored
using the same
1039 credentials as they are created on the guest
. This requires QEMU
1040 to run as root
. In
"mapped-xattr" security model
, some of the file
1041 attributes like uid
, gid
, mode bits and link target are stored as
1042 file attributes
. For
"mapped-file" these attributes are stored
in the
1043 hidden
.virtfs_metadata directory
. Directories exported by
this security model cannot
1044 interact with other unix tools
. "none" security model is same as
1045 passthrough except the sever won
't report failures if it fails to
1046 set file attributes like ownership. Security model is mandatory
1047 only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
1048 security model as a parameter
.
1049 @item writeout
=@
var{writeout
}
1050 This is an optional argument
. The only supported value is
"immediate".
1051 This means that host page cache will be used to read and write data but
1052 write notification will be sent to the guest only when the data has been
1053 reported as written by the storage subsystem
.
1055 Enables exporting
9p share as a readonly mount
for guests
. By
default
1056 read
-write access is given
.
1057 @item socket
=@
var{socket
}
1058 Enables proxy filesystem driver to use passed socket file
for communicating
1059 with virtfs
-proxy
-helper
1060 @item sock_fd
=@
var{sock_fd
}
1061 Enables proxy filesystem driver to use passed socket descriptor
for
1062 communicating with virtfs
-proxy
-helper
. Usually a helper like libvirt
1063 will create socketpair and pass one of the fds as sock_fd
1064 @item fmode
=@
var{fmode
}
1065 Specifies the
default mode
for newly created files on the host
. Works only
1066 with security models
"mapped-xattr" and
"mapped-file".
1067 @item dmode
=@
var{dmode
}
1068 Specifies the
default mode
for newly created directories on the host
. Works
1069 only with security models
"mapped-xattr" and
"mapped-file".
1072 -fsdev option is used along with
-device driver
"virtio-9p-pci".
1073 @item
-device virtio
-9p
-pci
,fsdev
=@
var{id
},mount_tag
=@
var{mount_tag
}
1074 Options
for virtio
-9p
-pci driver are
:
1076 @item fsdev
=@
var{id
}
1077 Specifies the id value specified along with
-fsdev option
1078 @item mount_tag
=@
var{mount_tag
}
1079 Specifies the tag name to be used by the guest to mount
this export point
1084 DEF("virtfs", HAS_ARG
, QEMU_OPTION_virtfs
,
1085 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
1086 " [,id=id][,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n",
1091 @item
-virtfs @
var{fsdriver
}[,path
=@
var{path
}],mount_tag
=@
var{mount_tag
}[,security_model
=@
var{security_model
}][,writeout
=@
var{writeout
}][,readonly
][,socket
=@
var{socket
}|sock_fd
=@
var{sock_fd
}][,fmode
=@
var{fmode
}][,dmode
=@
var{dmode
}]
1094 The general form of a Virtual File system pass
-through options are
:
1096 @item @
var{fsdriver
}
1097 This option specifies the fs driver backend to use
.
1098 Currently
"local", "handle" and
"proxy" file system drivers are supported
.
1100 Specifies identifier
for this device
1101 @item path
=@
var{path
}
1102 Specifies the export path
for the file system device
. Files under
1103 this path will be available to the
9p client on the guest
.
1104 @item security_model
=@
var{security_model
}
1105 Specifies the security model to be used
for this export path
.
1106 Supported security models are
"passthrough", "mapped-xattr", "mapped-file" and
"none".
1107 In
"passthrough" security model
, files are stored
using the same
1108 credentials as they are created on the guest
. This requires QEMU
1109 to run as root
. In
"mapped-xattr" security model
, some of the file
1110 attributes like uid
, gid
, mode bits and link target are stored as
1111 file attributes
. For
"mapped-file" these attributes are stored
in the
1112 hidden
.virtfs_metadata directory
. Directories exported by
this security model cannot
1113 interact with other unix tools
. "none" security model is same as
1114 passthrough except the sever won
't report failures if it fails to
1115 set file attributes like ownership. Security model is mandatory only
1116 for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
1117 model as a parameter
.
1118 @item writeout
=@
var{writeout
}
1119 This is an optional argument
. The only supported value is
"immediate".
1120 This means that host page cache will be used to read and write data but
1121 write notification will be sent to the guest only when the data has been
1122 reported as written by the storage subsystem
.
1124 Enables exporting
9p share as a readonly mount
for guests
. By
default
1125 read
-write access is given
.
1126 @item socket
=@
var{socket
}
1127 Enables proxy filesystem driver to use passed socket file
for
1128 communicating with virtfs
-proxy
-helper
. Usually a helper like libvirt
1129 will create socketpair and pass one of the fds as sock_fd
1131 Enables proxy filesystem driver to use passed
'sock_fd' as the socket
1132 descriptor
for interfacing with virtfs
-proxy
-helper
1133 @item fmode
=@
var{fmode
}
1134 Specifies the
default mode
for newly created files on the host
. Works only
1135 with security models
"mapped-xattr" and
"mapped-file".
1136 @item dmode
=@
var{dmode
}
1137 Specifies the
default mode
for newly created directories on the host
. Works
1138 only with security models
"mapped-xattr" and
"mapped-file".
1142 DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth
,
1143 "-virtfs_synth Create synthetic file system image\n",
1147 @findex
-virtfs_synth
1148 Create synthetic file system image
1156 DEFHEADING(USB options
)
1161 DEF("usb", 0, QEMU_OPTION_usb
,
1162 "-usb enable the USB driver (if it is not used by default yet)\n",
1167 Enable the USB
driver (if it is not used by
default yet
).
1170 DEF("usbdevice", HAS_ARG
, QEMU_OPTION_usbdevice
,
1171 "-usbdevice name add the host or guest USB device 'name'\n",
1175 @item
-usbdevice @
var{devname
}
1177 Add the USB device @
var{devname
}. Note that
this option is deprecated
,
1178 please use @code
{-device usb
-...} instead
. @xref
{usb_devices
}.
1183 Virtual Mouse
. This will
override the PS
/2 mouse emulation when activated
.
1186 Pointer device that uses absolute
coordinates (like a touchscreen
). This
1187 means QEMU is able to report the mouse position without having to grab the
1188 mouse
. Also overrides the PS
/2 mouse emulation when activated
.
1190 @item disk
:[format
=@
var{format
}]:@
var{file
}
1191 Mass storage device based on file
. The optional @
var{format
} argument
1192 will be used rather than detecting the format
. Can be used to specify
1193 @code
{format
=raw
} to avoid interpreting an untrusted format header
.
1195 @item host
:@
var{bus
}.@
var{addr
}
1196 Pass through the host device identified by @
var{bus
}.@
var{addr
} (Linux only
).
1198 @item host
:@
var{vendor_id
}:@
var{product_id
}
1199 Pass through the host device identified by @
var{vendor_id
}:@
var{product_id
}
1202 @item serial
:[vendorid
=@
var{vendor_id
}][,productid
=@
var{product_id
}]:@
var{dev
}
1203 Serial converter to host character device @
var{dev
}, see @code
{-serial
} for the
1207 Braille device
. This will use BrlAPI to display the braille output on a real
1210 @item net
:@
var{options
}
1211 Network adapter that supports CDC ethernet and RNDIS protocols
.
1221 DEFHEADING(Display options
)
1226 DEF("display", HAS_ARG
, QEMU_OPTION_display
,
1227 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
1228 " [,window_close=on|off][,gl=on|off]\n"
1229 "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n"
1230 "-display vnc=<display>[,<optargs>]\n"
1233 " select display type\n"
1234 "The default display is equivalent to\n"
1235 #
if defined(CONFIG_GTK
)
1236 "\t\"-display gtk\"\n"
1237 #elif
defined(CONFIG_SDL
)
1238 "\t\"-display sdl\"\n"
1239 #elif
defined(CONFIG_COCOA
)
1240 "\t\"-display cocoa\"\n"
1241 #elif
defined(CONFIG_VNC
)
1242 "\t\"-vnc localhost:0,to=99,id=default\"\n"
1244 "\t\"-display none\"\n"
1248 @item
-display @
var{type
}
1250 Select type of display to use
. This option is a replacement
for the
1251 old style
-sdl
/-curses
/... options
. Valid values
for @
var{type
} are
1254 Display video output via
SDL (usually
in a separate graphics
1255 window
; see the SDL documentation
for other possibilities
).
1257 Display video output via curses
. For graphics device models which
1258 support a text mode
, QEMU can display
this output
using a
1259 curses
/ncurses
interface. Nothing is displayed when the graphics
1260 device is
in graphical mode or
if the graphics device does not support
1261 a text mode
. Generally only the VGA device models support text mode
.
1263 Do not display video output
. The guest will still see an emulated
1264 graphics card
, but its output will not be displayed to the QEMU
1265 user
. This option differs from the
-nographic option
in that it
1266 only affects what is done with video output
; -nographic also changes
1267 the destination of the serial and parallel port data
.
1269 Display video output
in a GTK window
. This
interface provides drop
-down
1270 menus and other UI elements to configure and control the VM during
1273 Start a VNC server on display
<arg
>
1277 DEF("nographic", 0, QEMU_OPTION_nographic
,
1278 "-nographic disable graphical output and redirect serial I/Os to console\n",
1283 Normally
, if QEMU is compiled with graphical window support
, it displays
1284 output such as guest graphics
, guest console
, and the QEMU monitor
in a
1285 window
. With
this option
, you can totally disable graphical output so
1286 that QEMU is a simple command line application
. The emulated serial port
1287 is redirected on the console and muxed with the
monitor (unless
1288 redirected elsewhere explicitly
). Therefore
, you can still use QEMU to
1289 debug a Linux kernel with a serial console
. Use @key
{C
-a h
} for help on
1290 switching between the console and monitor
.
1293 DEF("curses", 0, QEMU_OPTION_curses
,
1294 "-curses shorthand for -display curses\n",
1299 Normally
, if QEMU is compiled with graphical window support
, it displays
1300 output such as guest graphics
, guest console
, and the QEMU monitor
in a
1301 window
. With
this option
, QEMU can display the VGA output when
in text
1302 mode
using a curses
/ncurses
interface. Nothing is displayed
in graphical
1306 DEF("no-frame", 0, QEMU_OPTION_no_frame
,
1307 "-no-frame open SDL window without a frame and window decorations\n",
1312 Do not use decorations
for SDL windows and start them
using the whole
1313 available screen space
. This makes the
using QEMU
in a dedicated desktop
1314 workspace more convenient
.
1317 DEF("alt-grab", 0, QEMU_OPTION_alt_grab
,
1318 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
1323 Use Ctrl
-Alt
-Shift to grab
mouse (instead of Ctrl
-Alt
). Note that
this also
1324 affects the special
keys (for fullscreen
, monitor
-mode switching
, etc
).
1327 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab
,
1328 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
1333 Use Right
-Ctrl to grab
mouse (instead of Ctrl
-Alt
). Note that
this also
1334 affects the special
keys (for fullscreen
, monitor
-mode switching
, etc
).
1337 DEF("no-quit", 0, QEMU_OPTION_no_quit
,
1338 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL
)
1342 Disable SDL window close capability
.
1345 DEF("sdl", 0, QEMU_OPTION_sdl
,
1346 "-sdl shorthand for -display sdl\n", QEMU_ARCH_ALL
)
1353 DEF("spice", HAS_ARG
, QEMU_OPTION_spice
,
1354 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
1355 " [,x509-key-file=<file>][,x509-key-password=<file>]\n"
1356 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
1357 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n"
1358 " [,tls-ciphers=<list>]\n"
1359 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
1360 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
1361 " [,sasl][,password=<secret>][,disable-ticketing]\n"
1362 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
1363 " [,jpeg-wan-compression=[auto|never|always]]\n"
1364 " [,zlib-glz-wan-compression=[auto|never|always]]\n"
1365 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
1366 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
1367 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
1368 " [,gl=[on|off]][,rendernode=<file>]\n"
1370 " at least one of {port, tls-port} is mandatory\n",
1373 @item
-spice @
var{option
}[,@
var{option
}[,...]]
1375 Enable the spice remote desktop protocol
. Valid options are
1380 Set the TCP port spice is listening on
for plaintext channels
.
1383 Set the IP address spice is listening on
. Default is any address
.
1388 Force
using the specified IP version
.
1390 @item password
=<secret
>
1391 Set the password you need to authenticate
.
1394 Require that the client use SASL to authenticate with the spice
.
1395 The exact choice of authentication method used is controlled from the
1396 system
/ user
's SASL configuration file for the 'qemu
' service. This
1397 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1398 unprivileged user, an environment variable SASL_CONF_PATH can be used
1399 to make it search alternate locations for the service config.
1400 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1401 it is recommended that SASL always be combined with the 'tls
' and
1402 'x509
' settings to enable use of SSL and server certificates. This
1403 ensures a data encryption preventing compromise of authentication
1406 @item disable-ticketing
1407 Allow client connects without authentication.
1409 @item disable-copy-paste
1410 Disable copy paste between the client and the guest.
1412 @item disable-agent-file-xfer
1413 Disable spice-vdagent based file-xfer between the client and the guest.
1416 Set the TCP port spice is listening on for encrypted channels.
1418 @item x509-dir=<dir>
1419 Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1421 @item x509-key-file=<file>
1422 @itemx x509-key-password=<file>
1423 @itemx x509-cert-file=<file>
1424 @itemx x509-cacert-file=<file>
1425 @itemx x509-dh-key-file=<file>
1426 The x509 file names can also be configured individually.
1428 @item tls-ciphers=<list>
1429 Specify which ciphers to use.
1431 @item tls-channel=[main|display|cursor|inputs|record|playback]
1432 @itemx plaintext-channel=[main|display|cursor|inputs|record|playback]
1433 Force specific channel to be used with or without TLS encryption. The
1434 options can be specified multiple times to configure multiple
1435 channels. The special name "default" can be used to set the default
1436 mode. For channels which are not explicitly forced into one mode the
1437 spice client is allowed to pick tls/plaintext as he pleases.
1439 @item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1440 Configure image compression (lossless).
1441 Default is auto_glz.
1443 @item jpeg-wan-compression=[auto|never|always]
1444 @itemx zlib-glz-wan-compression=[auto|never|always]
1445 Configure wan image compression (lossy for slow links).
1448 @item streaming-video=[off|all|filter]
1449 Configure video stream detection. Default is off.
1451 @item agent-mouse=[on|off]
1452 Enable/disable passing mouse events via vdagent. Default is on.
1454 @item playback-compression=[on|off]
1455 Enable/disable audio stream compression (using celt 0.5.1). Default is on.
1457 @item seamless-migration=[on|off]
1458 Enable/disable spice seamless migration. Default is off.
1461 Enable/disable OpenGL context. Default is off.
1463 @item rendernode=<file>
1464 DRM render node for OpenGL rendering. If not specified, it will pick
1465 the first available. (Since 2.9)
1470 DEF("portrait", 0, QEMU_OPTION_portrait,
1471 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
1476 Rotate graphical output 90 deg left (only PXA LCD).
1479 DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1480 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
1483 @item -rotate @var{deg}
1485 Rotate graphical output some deg left (only PXA LCD).
1488 DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1489 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n"
1490 " select video card type\n", QEMU_ARCH_ALL)
1492 @item -vga @var{type}
1494 Select type of VGA card to emulate. Valid values for @var{type} are
1497 Cirrus Logic GD5446 Video card. All Windows versions starting from
1498 Windows 95 should recognize and use this graphic card. For optimal
1499 performances, use 16 bit color depth in the guest and the host OS.
1500 (This card was the default before QEMU 2.2)
1502 Standard VGA card with Bochs VBE extensions. If your guest OS
1503 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1504 to use high resolution modes (>= 1280x1024x16) then you should use
1505 this option. (This card is the default since QEMU 2.2)
1507 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1508 recent XFree86/XOrg server or Windows guest with a driver for this
1511 QXL paravirtual graphic card. It is VGA compatible (including VESA
1512 2.0 VBE support). Works best with qxl guest drivers installed though.
1513 Recommended choice when using the spice protocol.
1515 (sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1516 sun4m machines and offers both 8-bit and 24-bit colour depths at a
1517 fixed resolution of 1024x768.
1519 (sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1520 for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1521 resolutions aimed at people wishing to run older Solaris versions.
1529 DEF("full-screen", 0, QEMU_OPTION_full_screen,
1530 "-full-screen start in full screen\n", QEMU_ARCH_ALL)
1533 @findex -full-screen
1534 Start in full screen.
1537 DEF("g", 1, QEMU_OPTION_g ,
1538 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
1539 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1541 @item -g @var{width}x@var{height}[x@var{depth}]
1543 Set the initial graphical resolution and depth (PPC, SPARC only).
1546 DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1547 "-vnc <display> shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL)
1549 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1551 Normally, if QEMU is compiled with graphical window support, it displays
1552 output such as guest graphics, guest console, and the QEMU monitor in a
1553 window. With this option, you can have QEMU listen on VNC display
1554 @var{display} and redirect the VGA display over the VNC session. It is
1555 very useful to enable the usb tablet device when using this option
1556 (option @option{-device usb-tablet}). When using the VNC display, you
1557 must use the @option{-k} parameter to set the keyboard layout if you are
1558 not using en-us. Valid syntax for the @var{display} is
1564 With this option, QEMU will try next available VNC @var{display}s, until the
1565 number @var{L}, if the origianlly defined "-vnc @var{display}" is not
1566 available, e.g. port 5900+@var{display} is already used by another
1567 application. By default, to=0.
1569 @item @var{host}:@var{d}
1571 TCP connections will only be allowed from @var{host} on display @var{d}.
1572 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1573 be omitted in which case the server will accept connections from any host.
1575 @item unix:@var{path}
1577 Connections will be allowed over UNIX domain sockets where @var{path} is the
1578 location of a unix socket to listen for connections on.
1582 VNC is initialized but not started. The monitor @code{change} command
1583 can be used to later start the VNC server.
1587 Following the @var{display} value there may be one or more @var{option} flags
1588 separated by commas. Valid options are
1594 Connect to a listening VNC client via a ``reverse'' connection. The
1595 client is specified by the @var{display}. For reverse network
1596 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1597 is a TCP port number, not a display number.
1601 Opens an additional TCP listening port dedicated to VNC Websocket connections.
1602 If a bare @var{websocket} option is given, the Websocket port is
1603 5700+@var{display}. An alternative port can be specified with the
1604 syntax @code{websocket}=@var{port}.
1606 If @var{host} is specified connections will only be allowed from this host.
1607 It is possible to control the websocket listen address independently, using
1608 the syntax @code{websocket}=@var{host}:@var{port}.
1610 If no TLS credentials are provided, the websocket connection runs in
1611 unencrypted mode. If TLS credentials are provided, the websocket connection
1612 requires encrypted client connections.
1616 Require that password based authentication is used for client connections.
1618 The password must be set separately using the @code{set_password} command in
1619 the @ref{pcsys_monitor}. The syntax to change your password is:
1620 @code{set_password <protocol> <password>} where <protocol> could be either
1623 If you would like to change <protocol> password expiration, you should use
1624 @code{expire_password <protocol> <expiration-time>} where expiration time could
1625 be one of the following options: now, never, +seconds or UNIX time of
1626 expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1627 to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1630 You can also use keywords "now" or "never" for the expiration time to
1631 allow <protocol> password to expire immediately or never expire.
1633 @item tls-creds=@var{ID}
1635 Provides the ID of a set of TLS credentials to use to secure the
1636 VNC server. They will apply to both the normal VNC server socket
1637 and the websocket socket (if enabled). Setting TLS credentials
1638 will cause the VNC server socket to enable the VeNCrypt auth
1639 mechanism. The credentials should have been previously created
1640 using the @option{-object tls-creds} argument.
1642 The @option{tls-creds} parameter obsoletes the @option{tls},
1643 @option{x509}, and @option{x509verify} options, and as such
1644 it is not permitted to set both new and old type options at
1649 Require that client use TLS when communicating with the VNC server. This
1650 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1651 attack. It is recommended that this option be combined with either the
1652 @option{x509} or @option{x509verify} options.
1654 This option is now deprecated in favor of using the @option{tls-creds}
1657 @item x509=@var{/path/to/certificate/dir}
1659 Valid if @option{tls} is specified. Require that x509 credentials are used
1660 for negotiating the TLS session. The server will send its x509 certificate
1661 to the client. It is recommended that a password be set on the VNC server
1662 to provide authentication of the client when this is used. The path following
1663 this option specifies where the x509 certificates are to be loaded from.
1664 See the @ref{vnc_security} section for details on generating certificates.
1666 This option is now deprecated in favour of using the @option{tls-creds}
1669 @item x509verify=@var{/path/to/certificate/dir}
1671 Valid if @option{tls} is specified. Require that x509 credentials are used
1672 for negotiating the TLS session. The server will send its x509 certificate
1673 to the client, and request that the client send its own x509 certificate.
1674 The server will validate the client's certificate against the CA certificate
,
1675 and reject clients when validation fails
. If the certificate authority is
1676 trusted
, this is a sufficient authentication mechanism
. You may still wish
1677 to set a password on the VNC server as a second authentication layer
. The
1678 path following
this option specifies where the x509 certificates are to
1679 be loaded from
. See the @ref
{vnc_security
} section
for details on generating
1682 This option is now deprecated
in favour of
using the @option
{tls
-creds
}
1687 Require that the client use SASL to authenticate with the VNC server
.
1688 The exact choice of authentication method used is controlled from the
1689 system
/ user
's SASL configuration file for the 'qemu
' service. This
1690 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1691 unprivileged user, an environment variable SASL_CONF_PATH can be used
1692 to make it search alternate locations for the service config.
1693 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1694 it is recommended that SASL always be combined with the 'tls
' and
1695 'x509
' settings to enable use of SSL and server certificates. This
1696 ensures a data encryption preventing compromise of authentication
1697 credentials. See the @ref{vnc_security} section for details on using
1698 SASL authentication.
1702 Turn on access control lists for checking of the x509 client certificate
1703 and SASL party. For x509 certs, the ACL check is made against the
1704 certificate's distinguished name
. This is something that looks like
1705 @code
{C
=GB
,O
=ACME
,L
=Boston
,CN
=bob
}. For SASL party
, the ACL check is
1706 made against the username
, which depending on the SASL plugin
, may
1707 include a realm component
, eg @code
{bob
} or @code
{bob@@EXAMPLE
.COM
}.
1708 When the @option
{acl
} flag is set
, the initial access list will be
1709 empty
, with a @code
{deny
} policy
. Thus no one will be allowed to
1710 use the VNC server until the ACLs have been loaded
. This can be
1711 achieved
using the @code
{acl
} monitor command
.
1715 Enable lossy compression
methods (gradient
, JPEG
, ...). If
this
1716 option is set
, VNC client may receive lossy framebuffer updates
1717 depending on its encoding settings
. Enabling
this option can save
1718 a lot of bandwidth at the expense of quality
.
1722 Disable adaptive encodings
. Adaptive encodings are enabled by
default.
1723 An adaptive encoding will
try to detect frequently updated screen regions
,
1724 and send updates
in these regions
using a lossy
encoding (like JPEG
).
1725 This can be really helpful to save bandwidth when playing videos
. Disabling
1726 adaptive encodings restores the original
static behavior of encodings
1729 @item share
=[allow
-exclusive|force
-shared|ignore
]
1731 Set display sharing policy
. 'allow-exclusive' allows clients to ask
1732 for exclusive access
. As suggested by the rfb spec
this is
1733 implemented by dropping other connections
. Connecting multiple
1734 clients
in parallel requires all clients asking
for a shared session
1735 (vncviewer
: -shared
switch). This is the
default. 'force-shared'
1736 disables exclusive client access
. Useful
for shared desktop sessions
,
1737 where you don
't want someone forgetting specify -shared disconnect
1738 everybody else. 'ignore
' completely ignores the shared flag and
1739 allows everybody connect unconditionally. Doesn't conform to the rfb
1740 spec but is traditional QEMU behavior
.
1744 Set keyboard delay
, for key down and key up events
, in milliseconds
.
1745 Default is
1. Keyboards are low
-bandwidth devices
, so
this slowdown
1746 can help the device and guest to keep up and not lose events
in case
1747 events are arriving
in bulk
. Possible causes
for the latter are flaky
1748 network connections
, or scripts
for automated testing
.
1756 ARCHHEADING(, QEMU_ARCH_I386
)
1758 ARCHHEADING(i386 target only
, QEMU_ARCH_I386
)
1763 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack
,
1764 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1769 Use it when installing Windows
2000 to avoid a disk full bug
. After
1770 Windows
2000 is installed
, you no longer need
this option (this option
1771 slows down the IDE transfers
).
1774 HXCOMM Deprecated by
-rtc
1775 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack
, "", QEMU_ARCH_I386
)
1777 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk
,
1778 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1781 @item
-no
-fd
-bootchk
1782 @findex
-no
-fd
-bootchk
1783 Disable boot signature checking
for floppy disks
in BIOS
. May
1784 be needed to boot from old floppy disks
.
1787 DEF("no-acpi", 0, QEMU_OPTION_no_acpi
,
1788 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM
)
1792 Disable
ACPI (Advanced Configuration and Power Interface
) support
. Use
1793 it
if your guest OS complains about ACPI
problems (PC target machine
1797 DEF("no-hpet", 0, QEMU_OPTION_no_hpet
,
1798 "-no-hpet disable HPET\n", QEMU_ARCH_I386
)
1802 Disable HPET support
.
1805 DEF("acpitable", HAS_ARG
, QEMU_OPTION_acpitable
,
1806 "-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"
1807 " ACPI table description\n", QEMU_ARCH_I386
)
1809 @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
}]...]
1811 Add ACPI table with specified header fields and context from specified files
.
1812 For file
=, take whole ACPI table from the specified files
, including all
1813 ACPI
headers (possible overridden by other options
).
1814 For data
=, only data
1815 portion of the table is used
, all header information is specified
in the
1817 If a SLIC table is supplied to QEMU
, then the SLIC
's oem_id and oem_table_id
1818 fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order
1819 to ensure the field matches required by the Microsoft SLIC spec and the ACPI
1823 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1824 "-smbios file=binary\n"
1825 " load SMBIOS entry from binary file\n"
1826 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1828 " specify SMBIOS type 0 fields\n"
1829 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1830 " [,uuid=uuid][,sku=str][,family=str]\n"
1831 " specify SMBIOS type 1 fields\n"
1832 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1833 " [,asset=str][,location=str]\n"
1834 " specify SMBIOS type 2 fields\n"
1835 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n"
1837 " specify SMBIOS type 3 fields\n"
1838 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n"
1839 " [,asset=str][,part=str]\n"
1840 " specify SMBIOS type 4 fields\n"
1841 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n"
1842 " [,asset=str][,part=str][,speed=%d]\n"
1843 " specify SMBIOS type 17 fields\n",
1844 QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1846 @item -smbios file=@var{binary}
1848 Load SMBIOS entry from binary file.
1850 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1851 Specify SMBIOS type 0 fields
1853 @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}]
1854 Specify SMBIOS type 1 fields
1856 @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}]
1857 Specify SMBIOS type 2 fields
1859 @item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}]
1860 Specify SMBIOS type 3 fields
1862 @item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}]
1863 Specify SMBIOS type 4 fields
1865 @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}]
1866 Specify SMBIOS type 17 fields
1874 DEFHEADING(Network options)
1879 HXCOMM Legacy slirp options (now moved to -net user):
1881 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1882 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1883 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1885 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1889 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1891 "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n"
1892 " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n"
1893 " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n"
1894 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,tftp=dir]\n"
1895 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1897 "[,smb=dir[,smbserver=addr]]\n"
1899 " configure a user mode network backend with ID 'str
',\n"
1900 " its DHCP server and optional services\n"
1903 "-netdev tap,id=str,ifname=name\n"
1904 " configure a host TAP network backend with ID 'str
'\n"
1906 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n"
1907 " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n"
1908 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n"
1910 " configure a host TAP network backend with ID 'str
'\n"
1911 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1912 " use network scripts 'file
' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1913 " to configure it and 'dfile
' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1914 " to deconfigure it\n"
1915 " use '[down
]script
=no
' to disable script execution\n"
1916 " use network helper 'helper
' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1918 " use 'fd
=h
' to connect to an already opened TAP interface\n"
1919 " use 'fds
=x
:y
:...:z
' to connect to already opened multiqueue capable TAP interfaces\n"
1920 " use 'sndbuf
=nbytes
' to limit the size of the send buffer (the\n"
1921 " default is disabled 'sndbuf
=0' to enable flow control set 'sndbuf
=1048576')\n"
1922 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1923 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1924 " use vhost=on to enable experimental in kernel accelerator\n"
1925 " (only has effect for virtio guests which use MSIX)\n"
1926 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1927 " use 'vhostfd
=h
' to connect to an already opened vhost net device\n"
1928 " use 'vhostfds
=x
:y
:...:z to connect to multiple already opened vhost net devices
\n"
1929 " use
'queues=n' to specify the number of queues to be created
for multiqueue TAP
\n"
1930 " use
'poll-us=n' to speciy the maximum number of microseconds that could be
\n"
1931 " spent on busy polling
for vhost net
\n"
1932 "-netdev bridge
,id
=str
[,br
=bridge
][,helper
=helper
]\n"
1933 " configure a host TAP network backend with ID
'str' that is
\n"
1934 " connected to a
bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1935 " using the program
'helper (default=" DEFAULT_BRIDGE_HELPER ")\n"
1938 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n"
1939 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n"
1940 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n"
1941 " [,rxcookie=rxcookie][,offset=offset]\n"
1942 " configure a network backend with ID 'str
' connected to\n"
1943 " an Ethernet over L2TPv3 pseudowire.\n"
1944 " Linux kernel 3.3+ as well as most routers can talk\n"
1945 " L2TPv3. This transport allows connecting a VM to a VM,\n"
1946 " VM to a router and even VM to Host. It is a nearly-universal\n"
1947 " standard (RFC3391). Note - this implementation uses static\n"
1948 " pre-configured tunnels (same as the Linux kernel).\n"
1949 " use 'src
=' to specify source address\n"
1950 " use 'dst
=' to specify destination address\n"
1951 " use 'udp
=on
' to specify udp encapsulation\n"
1952 " use 'srcport
=' to specify source udp port\n"
1953 " use 'dstport
=' to specify destination udp port\n"
1954 " use 'ipv6
=on
' to force v6\n"
1955 " L2TPv3 uses cookies to prevent misconfiguration as\n"
1956 " well as a weak security measure\n"
1957 " use 'rxcookie
=0x012345678' to specify a rxcookie\n"
1958 " use 'txcookie
=0x012345678' to specify a txcookie\n"
1959 " use 'cookie64
=on
' to set cookie size to 64 bit, otherwise 32\n"
1960 " use 'counter
=off
' to force a 'cut
-down
' L2TPv3 with no counter\n"
1961 " use 'pincounter
=on
' to work around broken counter handling in peer\n"
1962 " use 'offset
=X
' to add an extra offset between header and data\n"
1964 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n"
1965 " configure a network backend to connect to another network\n"
1966 " using a socket connection\n"
1967 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1968 " configure a network backend to connect to a multicast maddr and port\n"
1969 " use 'localaddr
=addr
' to specify the host address to send packets from\n"
1970 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
1971 " configure a network backend to connect to another network\n"
1972 " using an UDP tunnel\n"
1974 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1975 " configure a network backend to connect to port 'n
' of a vde switch\n"
1976 " running on host and listening for incoming connections on 'socketpath
'.\n"
1977 " Use group 'groupname
' and mode 'octalmode
' to change default\n"
1978 " ownership and permissions for communication port.\n"
1980 #ifdef CONFIG_NETMAP
1981 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n"
1982 " attach to the existing netmap-enabled network interface 'name
', or to a\n"
1983 " VALE port (created on the fly) called 'name
' ('nmname
' is name of the \n"
1984 " netmap device, defaults to '/dev
/netmap
')\n"
1986 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n"
1987 " configure a vhost-user network, backed by a chardev 'dev
'\n"
1988 "-netdev hubport,id=str,hubid=n\n"
1989 " configure a hub port on QEMU VLAN 'n
'\n", QEMU_ARCH_ALL)
1990 DEF("net", HAS_ARG, QEMU_OPTION_net,
1991 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
1992 " old way to create a new NIC and connect it to VLAN 'n
'\n"
1993 " (use the '-device devtype
,netdev
=str
' option if possible instead)\n"
1994 "-net dump[,vlan=n][,file=f][,len=n]\n"
1995 " dump traffic on vlan 'n
' to file 'f
' (max n bytes per packet)\n"
1996 "-net none use it alone to have zero network devices. If no -net option\n"
1997 " is provided, the default is '-net nic
-net user
'\n"
2007 #ifdef CONFIG_NETMAP
2010 "socket][,vlan=n][,option][,option][,...]\n"
2011 " old way to initialize a host network interface\n"
2012 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL)
2014 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
2016 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
2017 = 0 is the default). The NIC is an e1000 by default on the PC
2018 target. Optionally, the MAC address can be changed to @var{mac}, the
2019 device address set to @var{addr} (PCI cards only),
2020 and a @var{name} can be assigned for use in monitor commands.
2021 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
2022 that the card should have; this option currently only affects virtio cards; set
2023 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
2024 NIC is created. QEMU can emulate several different models of network card.
2025 Valid values for @var{type} are
2026 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
2027 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
2028 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
2029 Not all devices are supported on all targets. Use @code{-net nic,model=help}
2030 for a list of available devices for your target.
2032 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
2034 @item -net user[,@var{option}][,@var{option}][,...]
2035 Use the user mode network stack which requires no administrator
2036 privilege to run. Valid options are:
2040 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
2043 @itemx name=@var{name}
2044 Assign symbolic name for use in monitor commands.
2046 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must
2047 be enabled. If neither is specified both protocols are enabled.
2049 @item net=@var{addr}[/@var{mask}]
2050 Set IP network address the guest will see. Optionally specify the netmask,
2051 either in the form a.b.c.d or as number of valid top-most bits. Default is
2054 @item host=@var{addr}
2055 Specify the guest-visible address of the host. Default is the 2nd IP in the
2056 guest network, i.e. x.x.x.2.
2058 @item ipv6-net=@var{addr}[/@var{int}]
2059 Set IPv6 network address the guest will see (default is fec0::/64). The
2060 network prefix is given in the usual hexadecimal IPv6 address
2061 notation. The prefix size is optional, and is given as the number of
2062 valid top-most bits (default is 64).
2064 @item ipv6-host=@var{addr}
2065 Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in
2066 the guest network, i.e. xxxx::2.
2068 @item restrict=on|off
2069 If this option is enabled, the guest will be isolated, i.e. it will not be
2070 able to contact the host and no guest IP packets will be routed over the host
2071 to the outside. This option does not affect any explicitly set forwarding rules.
2073 @item hostname=@var{name}
2074 Specifies the client hostname reported by the built-in DHCP server.
2076 @item dhcpstart=@var{addr}
2077 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
2078 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
2080 @item dns=@var{addr}
2081 Specify the guest-visible address of the virtual nameserver. The address must
2082 be different from the host address. Default is the 3rd IP in the guest network,
2085 @item ipv6-dns=@var{addr}
2086 Specify the guest-visible address of the IPv6 virtual nameserver. The address
2087 must be different from the host address. Default is the 3rd IP in the guest
2088 network, i.e. xxxx::3.
2090 @item dnssearch=@var{domain}
2091 Provides an entry for the domain-search list sent by the built-in
2092 DHCP server. More than one domain suffix can be transmitted by specifying
2093 this option multiple times. If supported, this will cause the guest to
2094 automatically try to append the given domain suffix(es) in case a domain name
2095 can not be resolved.
2099 qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
2102 @item tftp=@var{dir}
2103 When using the user mode network stack, activate a built-in TFTP
2104 server. The files in @var{dir} will be exposed as the root of a TFTP server.
2105 The TFTP client on the guest must be configured in binary mode (use the command
2106 @code{bin} of the Unix TFTP client).
2108 @item bootfile=@var{file}
2109 When using the user mode network stack, broadcast @var{file} as the BOOTP
2110 filename. In conjunction with @option{tftp}, this can be used to network boot
2111 a guest from a local directory.
2113 Example (using pxelinux):
2115 qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
2118 @item smb=@var{dir}[,smbserver=@var{addr}]
2119 When using the user mode network stack, activate a built-in SMB
2120 server so that Windows OSes can access to the host files in @file{@var{dir}}
2121 transparently. The IP address of the SMB server can be set to @var{addr}. By
2122 default the 4th IP in the guest network is used, i.e. x.x.x.4.
2124 In the guest Windows OS, the line:
2128 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
2129 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
2131 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
2133 Note that a SAMBA server must be installed on the host OS.
2134 QEMU was tested successfully with smbd versions from Red Hat 9,
2135 Fedora Core 3 and OpenSUSE 11.x.
2137 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
2138 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
2139 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
2140 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
2141 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
2142 be bound to a specific host interface. If no connection type is set, TCP is
2143 used. This option can be given multiple times.
2145 For example, to redirect host X11 connection from screen 1 to guest
2146 screen 0, use the following:
2150 qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
2151 # this host xterm should open in the guest X11 server
2155 To redirect telnet connections from host port 5555 to telnet port on
2156 the guest, use the following:
2160 qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
2161 telnet localhost 5555
2164 Then when you use on the host @code{telnet localhost 5555}, you
2165 connect to the guest telnet server.
2167 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
2168 @itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
2169 Forward guest TCP connections to the IP address @var{server} on port @var{port}
2170 to the character device @var{dev} or to a program executed by @var{cmd:command}
2171 which gets spawned for each connection. This option can be given multiple times.
2173 You can either use a chardev directly and have that one used throughout QEMU's
2174 lifetime
, like
in the following example
:
2177 # open
10.10.1.1:4321 on bootup
, connect
10.0.2.100:1234 to it whenever
2178 # the guest accesses it
2179 qemu
-net user
,guestfwd
=tcp
:10.0.2.100:1234-tcp
:10.10.1.1:4321 [...]
2182 Or you can execute a command on every TCP connection established by the guest
,
2183 so that QEMU behaves similar to an inetd process
for that virtual server
:
2186 # call
"netcat 10.10.1.1 4321" on every TCP connection to
10.0.2.100:1234
2187 # and connect the TCP stream to its stdin
/stdout
2188 qemu
-net
'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
2193 Note
: Legacy stand
-alone options
-tftp
, -bootp
, -smb and
-redir are still
2194 processed and applied to
-net user
. Mixing them with the
new configuration
2195 syntax gives undefined results
. Their use
for new applications is discouraged
2196 as they will be removed from future versions
.
2198 @item
-netdev tap
,id
=@
var{id
}[,fd
=@
var{h
}][,ifname
=@
var{name
}][,script
=@
var{file
}][,downscript
=@
var{dfile
}][,br
=@
var{bridge
}][,helper
=@
var{helper
}]
2199 @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
}]
2200 Connect the host TAP network
interface @
var{name
} to VLAN @
var{n
}.
2202 Use the network script @
var{file
} to configure it and the network script
2203 @
var{dfile
} to deconfigure it
. If @
var{name
} is not provided
, the OS
2204 automatically provides one
. The
default network configure script is
2205 @file
{/etc
/qemu
-ifup
} and the
default network deconfigure script is
2206 @file
{/etc
/qemu
-ifdown
}. Use @option
{script
=no
} or @option
{downscript
=no
}
2207 to disable script execution
.
2209 If running QEMU as an unprivileged user
, use the network helper
2210 @
var{helper
} to configure the TAP
interface and attach it to the bridge
.
2211 The
default network helper executable is @file
{/path
/to
/qemu
-bridge
-helper
}
2212 and the
default bridge device is @file
{br0
}.
2214 @option
{fd
}=@
var{h
} can be used to specify the handle of an already
2215 opened host TAP
interface.
2220 #launch a QEMU instance with the
default network script
2221 qemu
-system
-i386 linux
.img
-net nic
-net tap
2225 #launch a QEMU instance with two NICs
, each one connected
2227 qemu
-system
-i386 linux
.img \
2228 -net nic
,vlan
=0 -net tap
,vlan
=0,ifname
=tap0 \
2229 -net nic
,vlan
=1 -net tap
,vlan
=1,ifname
=tap1
2233 #launch a QEMU instance with the
default network helper to
2234 #connect a TAP device to bridge br0
2235 qemu
-system
-i386 linux
.img \
2236 -net nic
-net tap
,"helper=/path/to/qemu-bridge-helper"
2239 @item
-netdev bridge
,id
=@
var{id
}[,br
=@
var{bridge
}][,helper
=@
var{helper
}]
2240 @itemx
-net bridge
[,vlan
=@
var{n
}][,name
=@
var{name
}][,br
=@
var{bridge
}][,helper
=@
var{helper
}]
2241 Connect a host TAP network
interface to a host bridge device
.
2243 Use the network helper @
var{helper
} to configure the TAP
interface and
2244 attach it to the bridge
. The
default network helper executable is
2245 @file
{/path
/to
/qemu
-bridge
-helper
} and the
default bridge
2246 device is @file
{br0
}.
2251 #launch a QEMU instance with the
default network helper to
2252 #connect a TAP device to bridge br0
2253 qemu
-system
-i386 linux
.img
-net bridge
-net nic
,model
=virtio
2257 #launch a QEMU instance with the
default network helper to
2258 #connect a TAP device to bridge qemubr0
2259 qemu
-system
-i386 linux
.img
-net bridge
,br
=qemubr0
-net nic
,model
=virtio
2262 @item
-netdev socket
,id
=@
var{id
}[,fd
=@
var{h
}][,listen
=[@
var{host
}]:@
var{port
}][,connect
=@
var{host
}:@
var{port
}]
2263 @itemx
-net socket
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}] [,listen
=[@
var{host
}]:@
var{port
}][,connect
=@
var{host
}:@
var{port
}]
2265 Connect the VLAN @
var{n
} to a remote VLAN
in another QEMU virtual
2266 machine
using a TCP socket connection
. If @option
{listen
} is
2267 specified
, QEMU waits
for incoming connections on @
var{port
}
2268 (@
var{host
} is optional
). @option
{connect
} is used to connect to
2269 another QEMU instance
using the @option
{listen
} option
. @option
{fd
}=@
var{h
}
2270 specifies an already opened TCP socket
.
2274 # launch a first QEMU instance
2275 qemu
-system
-i386 linux
.img \
2276 -net nic
,macaddr
=52:54:00:12:34:56 \
2277 -net socket
,listen
=:1234
2278 # connect the VLAN
0 of
this instance to the VLAN
0
2279 # of the first instance
2280 qemu
-system
-i386 linux
.img \
2281 -net nic
,macaddr
=52:54:00:12:34:57 \
2282 -net socket
,connect
=127.0.0.1:1234
2285 @item
-netdev socket
,id
=@
var{id
}[,fd
=@
var{h
}][,mcast
=@
var{maddr
}:@
var{port
}[,localaddr
=@
var{addr
}]]
2286 @itemx
-net socket
[,vlan
=@
var{n
}][,name
=@
var{name
}][,fd
=@
var{h
}][,mcast
=@
var{maddr
}:@
var{port
}[,localaddr
=@
var{addr
}]]
2288 Create a VLAN @
var{n
} shared with another QEMU virtual
2289 machines
using a UDP multicast socket
, effectively making a bus
for
2290 every QEMU with same multicast address @
var{maddr
} and @
var{port
}.
2294 Several QEMU can be running on different hosts and share same
bus (assuming
2295 correct multicast setup
for these hosts
).
2297 mcast support is compatible with User Mode
Linux (argument @option
{eth@
var{N
}=mcast
}), see
2298 @url
{http
://user-mode-linux.sf.net}.
2300 Use @option
{fd
=h
} to specify an already opened UDP multicast socket
.
2305 # launch one QEMU instance
2306 qemu
-system
-i386 linux
.img \
2307 -net nic
,macaddr
=52:54:00:12:34:56 \
2308 -net socket
,mcast
=230.0.0.1:1234
2309 # launch another QEMU instance on same
"bus"
2310 qemu
-system
-i386 linux
.img \
2311 -net nic
,macaddr
=52:54:00:12:34:57 \
2312 -net socket
,mcast
=230.0.0.1:1234
2313 # launch yet another QEMU instance on same
"bus"
2314 qemu
-system
-i386 linux
.img \
2315 -net nic
,macaddr
=52:54:00:12:34:58 \
2316 -net socket
,mcast
=230.0.0.1:1234
2319 Example (User Mode Linux compat
.):
2321 # launch QEMU
instance (note mcast address selected
2323 qemu-system-i386 linux.img \
2324 -net nic,macaddr=52:54:00:12:34:56 \
2325 -net socket,mcast=239.192.168.1:1102
2327 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
2330 Example (send packets from host's
1.2.3.4):
2332 qemu
-system
-i386 linux
.img \
2333 -net nic
,macaddr
=52:54:00:12:34:56 \
2334 -net socket
,mcast
=239.192.168.1:1102,localaddr
=1.2.3.4
2337 @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
}]
2338 @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
}]
2339 Connect VLAN @
var{n
} to L2TPv3 pseudowire
. L2TPv3 (RFC3391
) is a popular
2340 protocol to transport
Ethernet (and other Layer
2) data frames between
2341 two systems
. It is present
in routers
, firewalls and the Linux kernel
2342 (from version
3.3 onwards
).
2344 This transport allows a VM to communicate to another VM
, router or firewall directly
.
2346 @item src
=@
var{srcaddr
}
2347 source
address (mandatory
)
2348 @item dst
=@
var{dstaddr
}
2349 destination
address (mandatory
)
2351 select udp
encapsulation (default is ip
).
2352 @item srcport
=@
var{srcport
}
2354 @item dstport
=@
var{dstport
}
2355 destination udp port
.
2357 force v6
, otherwise defaults to v4
.
2358 @item rxcookie
=@
var{rxcookie
}
2359 @itemx txcookie
=@
var{txcookie
}
2360 Cookies are a weak form of security
in the l2tpv3 specification
.
2361 Their
function is mostly to prevent misconfiguration
. By
default they are
32
2364 Set cookie size to
64 bit instead of the
default 32
2366 Force a
'cut-down' L2TPv3 with no counter as
in
2367 draft
-mkonstan
-l2tpext
-keyed
-ipv6
-tunnel
-00
2369 Work around broken counter handling
in peer
. This may also help on
2370 networks which have packet reorder
.
2371 @item offset
=@
var{offset
}
2372 Add an extra offset between header and data
2374 For example
, to attach a VM running on host
4.3.2.1 via L2TPv3 to the bridge br
-lan
2375 on the remote Linux host
1.2.3.4:
2377 # Setup tunnel on linux host
using raw ip as encapsulation
2379 ip l2tp add tunnel remote
4.3.2.1 local
1.2.3.4 tunnel_id
1 peer_tunnel_id
1 \
2380 encap udp udp_sport
16384 udp_dport
16384
2381 ip l2tp add session tunnel_id
1 name vmtunnel0 session_id \
2382 0xFFFFFFFF peer_session_id
0xFFFFFFFF
2383 ifconfig vmtunnel0 mtu
1500
2384 ifconfig vmtunnel0 up
2385 brctl addif br
-lan vmtunnel0
2389 # launch QEMU instance
- if your network has reorder or is very lossy add
,pincounter
2391 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
2396 @item
-netdev vde
,id
=@
var{id
}[,sock
=@
var{socketpath
}][,port
=@
var{n
}][,group
=@
var{groupname
}][,mode
=@
var{octalmode
}]
2397 @itemx
-net vde
[,vlan
=@
var{n
}][,name
=@
var{name
}][,sock
=@
var{socketpath
}] [,port
=@
var{n
}][,group
=@
var{groupname
}][,mode
=@
var{octalmode
}]
2398 Connect VLAN @
var{n
} to PORT @
var{n
} of a vde
switch running on host and
2399 listening
for incoming connections on @
var{socketpath
}. Use GROUP @
var{groupname
}
2400 and MODE @
var{octalmode
} to change
default ownership and permissions
for
2401 communication port
. This option is only available
if QEMU has been compiled
2402 with vde support enabled
.
2407 vde_switch
-F
-sock
/tmp
/myswitch
2408 # launch QEMU instance
2409 qemu
-system
-i386 linux
.img
-net nic
-net vde
,sock
=/tmp
/myswitch
2412 @item
-netdev hubport
,id
=@
var{id
},hubid
=@
var{hubid
}
2414 Create a hub port on QEMU
"vlan" @
var{hubid
}.
2416 The hubport netdev lets you connect a NIC to a QEMU
"vlan" instead of a single
2417 netdev
. @code
{-net
} and @code
{-device
} with parameter @option
{vlan
} create the
2418 required hub automatically
.
2420 @item
-netdev vhost
-user
,chardev
=@
var{id
}[,vhostforce
=on|off
][,queues
=n
]
2422 Establish a vhost
-user netdev
, backed by a chardev @
var{id
}. The chardev should
2423 be a unix domain socket backed one
. The vhost
-user uses a specifically defined
2424 protocol to pass vhost ioctl replacement messages to an application on the other
2425 end of the socket
. On non
-MSIX guests
, the feature can be forced with
2426 @
var{vhostforce
}. Use
'queues=@var{n}' to specify the number of queues to
2427 be created
for multiqueue vhost
-user
.
2431 qemu
-m
512 -object memory
-backend
-file
,id
=mem
,size
=512M
,mem
-path
=/hugetlbfs
,share
=on \
2432 -numa node
,memdev
=mem \
2433 -chardev socket
,id
=chr0
,path
=/path
/to
/socket \
2434 -netdev type
=vhost
-user
,id
=net0
,chardev
=chr0 \
2435 -device virtio
-net
-pci
,netdev
=net0
2438 @item
-net dump
[,vlan
=@
var{n
}][,file
=@
var{file
}][,len
=@
var{len
}]
2439 Dump network traffic on VLAN @
var{n
} to file @
var{file
} (@file
{qemu
-vlan0
.pcap
} by
default).
2440 At most @
var{len
} bytes (64k by
default) per packet are stored
. The file format is
2441 libpcap
, so it can be analyzed with tools such as tcpdump or Wireshark
.
2442 Note
: For devices created with
'-netdev', use
'-object filter-dump,...' instead
.
2445 Indicate that no network devices should be configured
. It is used to
2446 override the
default configuration (@option
{-net nic
-net user
}) which
2447 is activated
if no @option
{-net
} options are provided
.
2455 DEFHEADING(Character device options
)
2458 The general form of a character device option is
:
2462 DEF("chardev", HAS_ARG
, QEMU_OPTION_chardev
,
2464 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2465 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
2466 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n"
2467 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n"
2468 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n"
2469 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n"
2470 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
2471 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
2472 " [,logfile=PATH][,logappend=on|off]\n"
2473 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2474 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
2475 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2476 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n"
2477 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2478 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2480 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2481 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2483 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2484 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n"
2486 #ifdef CONFIG_BRLAPI
2487 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2489 #
if defined(__linux__
) ||
defined(__sun__
) ||
defined(__FreeBSD__
) \
2490 ||
defined(__NetBSD__
) ||
defined(__OpenBSD__
) ||
defined(__DragonFly__
)
2491 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2492 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2494 #
if defined(__linux__
) ||
defined(__FreeBSD__
) ||
defined(__DragonFly__
)
2495 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2496 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2498 #
if defined(CONFIG_SPICE
)
2499 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2500 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2506 @item
-chardev @
var{backend
} ,id
=@
var{id
} [,mux
=on|off
] [,@
var{options
}]
2527 The specific backend will determine the applicable options
.
2529 Use
"-chardev help" to print all available chardev backend types
.
2531 All devices must have an id
, which can be any string up to
127 characters long
.
2532 It is used to uniquely identify
this device
in other command line directives
.
2534 A character device may be used
in multiplexing mode by multiple front
-ends
.
2535 Specify @option
{mux
=on
} to enable
this mode
.
2536 A multiplexer is a
"1:N" device
, and
here the
"1" end is your specified chardev
2537 backend
, and the
"N" end is the various parts of QEMU that can talk to a chardev
.
2538 If you create a chardev with @option
{id
=myid
} and @option
{mux
=on
}, QEMU will
2539 create a multiplexer with your specified ID
, and you can then configure multiple
2540 front ends to use that chardev ID
for their input
/output
. Up to four different
2541 front ends can be connected to a single multiplexed chardev
. (Without
2542 multiplexing enabled
, a chardev can only be used by a single front end
.)
2543 For instance you could use
this to allow a single stdio chardev to be used by
2544 two serial ports and the QEMU monitor
:
2547 -chardev stdio
,mux
=on
,id
=char0 \
2548 -mon chardev
=char0
,mode
=readline \
2549 -serial chardev
:char0 \
2550 -serial chardev
:char0
2553 You can have more than one multiplexer
in a system configuration
; for instance
2554 you could have a TCP port multiplexed between UART
0 and UART
1, and stdio
2555 multiplexed between the QEMU monitor and a parallel port
:
2558 -chardev stdio
,mux
=on
,id
=char0 \
2559 -mon chardev
=char0
,mode
=readline \
2560 -parallel chardev
:char0 \
2561 -chardev tcp
,...,mux
=on
,id
=char1 \
2562 -serial chardev
:char1 \
2563 -serial chardev
:char1
2566 When you
're using a multiplexed character device, some escape sequences are
2567 interpreted in the input. @xref{mux_keys, Keys in the character backend
2570 Note that some other command line options may implicitly create multiplexed
2571 character backends; for instance @option{-serial mon:stdio} creates a
2572 multiplexed stdio backend connected to the serial port and the QEMU monitor,
2573 and @option{-nographic} also multiplexes the console and the monitor to
2576 There is currently no support for multiplexing in the other direction
2577 (where a single QEMU front end takes input and output from multiple chardevs).
2579 Every backend supports the @option{logfile} option, which supplies the path
2580 to a file to record all data transmitted via the backend. The @option{logappend}
2581 option controls whether the log file will be truncated or appended to when
2584 Further options to each backend are described below.
2586 @item -chardev null ,id=@var{id}
2587 A void device. This device will not emit any data, and will drop any data it
2588 receives. The null backend does not take any options.
2590 @item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}] [,tls-creds=@var{id}]
2592 Create a two-way stream socket, which can be either a TCP or a unix socket. A
2593 unix socket will be created if @option{path} is specified. Behaviour is
2594 undefined if TCP options are specified for a unix socket.
2596 @option{server} specifies that the socket shall be a listening socket.
2598 @option{nowait} specifies that QEMU should not block waiting for a client to
2599 connect to a listening socket.
2601 @option{telnet} specifies that traffic on the socket should interpret telnet
2604 @option{reconnect} sets the timeout for reconnecting on non-server sockets when
2605 the remote end goes away. qemu will delay this many seconds and then attempt
2606 to reconnect. Zero disables reconnecting, and is the default.
2608 @option{tls-creds} requests enablement of the TLS protocol for encryption,
2609 and specifies the id of the TLS credentials to use for the handshake. The
2610 credentials must be previously created with the @option{-object tls-creds}
2613 TCP and unix socket options are given below:
2617 @item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
2619 @option{host} for a listening socket specifies the local address to be bound.
2620 For a connecting socket species the remote host to connect to. @option{host} is
2621 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
2623 @option{port} for a listening socket specifies the local port to be bound. For a
2624 connecting socket specifies the port on the remote host to connect to.
2625 @option{port} can be given as either a port number or a service name.
2626 @option{port} is required.
2628 @option{to} is only relevant to listening sockets. If it is specified, and
2629 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
2630 to and including @option{to} until it succeeds. @option{to} must be specified
2633 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2634 If neither is specified the socket may use either protocol.
2636 @option{nodelay} disables the Nagle algorithm.
2638 @item unix options: path=@var{path}
2640 @option{path} specifies the local path of the unix socket. @option{path} is
2645 @item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
2647 Sends all traffic from the guest to a remote host over UDP.
2649 @option{host} specifies the remote host to connect to. If not specified it
2650 defaults to @code{localhost}.
2652 @option{port} specifies the port on the remote host to connect to. @option{port}
2655 @option{localaddr} specifies the local address to bind to. If not specified it
2656 defaults to @code{0.0.0.0}.
2658 @option{localport} specifies the local port to bind to. If not specified any
2659 available local port will be used.
2661 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2662 If neither is specified the device may use either protocol.
2664 @item -chardev msmouse ,id=@var{id}
2666 Forward QEMU's emulated msmouse events to the guest
. @option
{msmouse
} does not
2669 @item
-chardev vc
,id
=@
var{id
} [[,width
=@
var{width
}] [,height
=@
var{height
}]] [[,cols
=@
var{cols
}] [,rows
=@
var{rows
}]]
2671 Connect to a QEMU text console
. @option
{vc
} may optionally be given a specific
2674 @option
{width
} and @option
{height
} specify the width and height respectively of
2675 the console
, in pixels
.
2677 @option
{cols
} and @option
{rows
} specify that the console be sized to fit a text
2678 console with the given dimensions
.
2680 @item
-chardev ringbuf
,id
=@
var{id
} [,size
=@
var{size
}]
2682 Create a ring buffer with fixed size @option
{size
}.
2683 @
var{size
} must be a power of two and defaults to @code
{64K
}.
2685 @item
-chardev file
,id
=@
var{id
} ,path
=@
var{path
}
2687 Log all traffic received from the guest to a file
.
2689 @option
{path
} specifies the path of the file to be opened
. This file will be
2690 created
if it does not already exist
, and overwritten
if it does
. @option
{path
}
2693 @item
-chardev pipe
,id
=@
var{id
} ,path
=@
var{path
}
2695 Create a two
-way connection to the guest
. The behaviour differs slightly between
2696 Windows hosts and other hosts
:
2698 On Windows
, a single duplex pipe will be created at
2699 @file
{\\.pipe\@option
{path
}}.
2701 On other hosts
, 2 pipes will be created called @file
{@option
{path
}.in} and
2702 @file
{@option
{path
}.out
}. Data written to @file
{@option
{path
}.in} will be
2703 received by the guest
. Data written by the guest can be read from
2704 @file
{@option
{path
}.out
}. QEMU will not create these fifos
, and requires them to
2707 @option
{path
} forms part of the pipe path as described above
. @option
{path
} is
2710 @item
-chardev console
,id
=@
var{id
}
2712 Send traffic from the guest to QEMU
's standard output. @option{console} does not
2715 @option{console} is only available on Windows hosts.
2717 @item -chardev serial ,id=@var{id} ,path=@option{path}
2719 Send traffic from the guest to a serial device on the host.
2721 On Unix hosts serial will actually accept any tty device,
2722 not only serial lines.
2724 @option{path} specifies the name of the serial device to open.
2726 @item -chardev pty ,id=@var{id}
2728 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2729 not take any options.
2731 @option{pty} is not available on Windows hosts.
2733 @item -chardev stdio ,id=@var{id} [,signal=on|off]
2734 Connect to standard input and standard output of the QEMU process.
2736 @option{signal} controls if signals are enabled on the terminal, that includes
2737 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2738 default, use @option{signal=off} to disable it.
2740 @item -chardev braille ,id=@var{id}
2742 Connect to a local BrlAPI server. @option{braille} does not take any options.
2744 @item -chardev tty ,id=@var{id} ,path=@var{path}
2746 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2747 DragonFlyBSD hosts. It is an alias for @option{serial}.
2749 @option{path} specifies the path to the tty. @option{path} is required.
2751 @item -chardev parallel ,id=@var{id} ,path=@var{path}
2752 @itemx -chardev parport ,id=@var{id} ,path=@var{path}
2754 @option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2756 Connect to a local parallel port.
2758 @option{path} specifies the path to the parallel port device. @option{path} is
2761 @item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2763 @option{spicevmc} is only available when spice support is built in.
2765 @option{debug} debug level for spicevmc
2767 @option{name} name of spice channel to connect to
2769 Connect to a spice virtual machine channel, such as vdiport.
2771 @item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2773 @option{spiceport} is only available when spice support is built in.
2775 @option{debug} debug level for spicevmc
2777 @option{name} name of spice port to connect to
2779 Connect to a spice port, allowing a Spice client to handle the traffic
2780 identified by a name (preferably a fqdn).
2788 DEFHEADING(Device URL Syntax)
2791 In addition to using normal file images for the emulated storage devices,
2792 QEMU can also use networked resources such as iSCSI devices. These are
2793 specified using a special URL syntax.
2797 iSCSI support allows QEMU to access iSCSI resources directly and use as
2798 images for the guest storage. Both disk and cdrom images are supported.
2800 Syntax for specifying iSCSI LUNs is
2801 ``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
2803 By default qemu will use the iSCSI initiator-name
2804 'iqn
.2008-11.org
.linux
-kvm
[:<name
>]' but this can also be set from the command
2805 line or a configuration file.
2807 Since version Qemu 2.4 it is possible to specify a iSCSI request timeout to detect
2808 stalled requests and force a reestablishment of the session. The timeout
2809 is specified in seconds. The default is 0 which means no timeout. Libiscsi
2810 1.15.0 or greater is required for this feature.
2812 Example (without authentication):
2814 qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
2815 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
2816 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2819 Example (CHAP username/password via URL):
2821 qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
2824 Example (CHAP username/password via environment variables):
2826 LIBISCSI_CHAP_USERNAME="user" \
2827 LIBISCSI_CHAP_PASSWORD="password" \
2828 qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2831 iSCSI support is an optional feature of QEMU and only available when
2832 compiled and linked against libiscsi.
2834 DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
2835 "-iscsi [user=user][,password=password]\n"
2836 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
2837 " [,initiator-name=initiator-iqn][,id=target-iqn]\n"
2838 " [,timeout=timeout]\n"
2839 " iSCSI session parameters\n", QEMU_ARCH_ALL)
2842 iSCSI parameters such as username and password can also be specified via
2843 a configuration file. See qemu-doc for more information and examples.
2846 QEMU supports NBD (Network Block Devices) both using TCP protocol as well
2847 as Unix Domain Sockets.
2849 Syntax for specifying a NBD device using TCP
2850 ``nbd:<server-ip>:<port>[:exportname=<export>]''
2852 Syntax for specifying a NBD device using Unix Domain Sockets
2853 ``nbd:unix:<domain-socket>[:exportname=<export>]''
2858 qemu-system-i386 --drive file=nbd:192.0.2.1:30000
2861 Example for Unix Domain Sockets
2863 qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket
2867 QEMU supports SSH (Secure Shell) access to remote disks.
2871 qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img
2872 qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img
2875 Currently authentication must be done using ssh-agent. Other
2876 authentication methods may be supported in future.
2879 Sheepdog is a distributed storage system for QEMU.
2880 QEMU supports using either local sheepdog devices or remote networked
2883 Syntax for specifying a sheepdog device
2885 sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag]
2890 qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine
2893 See also @url{https://sheepdog.github.io/sheepdog/}.
2896 GlusterFS is a user space distributed file system.
2897 QEMU supports the use of GlusterFS volumes for hosting VM disk images using
2898 TCP, Unix Domain Sockets and RDMA transport protocols.
2900 Syntax for specifying a VM disk image on GlusterFS volume is
2904 gluster[+type]://[host[:port]]/volume/path[?socket=...][,debug=N][,logfile=...]
2907 'json
:@
{"driver":"qcow2","file":@
{"driver":"gluster","volume":"testvol","path":"a.img","debug":N
,"logfile":"...",
2908 @
"server":[@
{"type":"tcp","host":"...","port":"..."@
},
2909 @ @
{"type":"unix","socket":"..."@
}]@
}@
}'
2916 qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img,
2917 @ file.debug=9,file.logfile=/var/log/qemu-gluster.log
2920 qemu-system-x86_64 'json
:@
{"driver":"qcow2",
2921 @
"file":@
{"driver":"gluster",
2922 @
"volume":"testvol","path":"a.img",
2923 @
"debug":9,"logfile":"/var/log/qemu-gluster.log",
2924 @
"server":[@
{"type":"tcp","host":"1.2.3.4","port":24007@
},
2925 @ @
{"type":"unix","socket":"/var/run/glusterd.socket"@
}]@
}@
}'
2926 qemu-system-x86_64 -drive driver=qcow2,file.driver=gluster,file.volume=testvol,file.path=/path/a.img,
2927 @ file.debug=9,file.logfile=/var/log/qemu-gluster.log,
2928 @ file.server.0.type=tcp,file.server.0.host=1.2.3.4,file.server.0.port=24007,
2929 @ file.server.1.type=unix,file.server.1.socket=/var/run/glusterd.socket
2932 See also @url{http://www.gluster.org}.
2934 @item HTTP/HTTPS/FTP/FTPS
2935 QEMU supports read-only access to files accessed over http(s) and ftp(s).
2937 Syntax using a single filename:
2939 <protocol>://[<username>[:<password>]@@]<host>/<path>
2945 'http
', 'https
', 'ftp
', or 'ftps
'.
2948 Optional username for authentication to the remote server.
2951 Optional password for authentication to the remote server.
2954 Address of the remote server.
2957 Path on the remote server, including any query string.
2960 The following options are also supported:
2963 The full URL when passing options to the driver explicitly.
2966 The amount of data to read ahead with each range request to the remote server.
2967 This value may optionally have the suffix 'T
', 'G
', 'M
', 'K
', 'k
' or 'b
'. If it
2968 does not have a suffix, it will be assumed to be in bytes. The value must be a
2969 multiple of 512 bytes. It defaults to 256k.
2972 Whether to verify the remote server's certificate when connecting over SSL
. It
2973 can have the value
'on' or
'off'. It defaults to
'on'.
2976 Send
this cookie (it can also be a list of cookies separated by
';') with
2977 each outgoing request
. Only supported when
using protocols such as HTTP
2978 which support cookies
, otherwise ignored
.
2981 Set the timeout
in seconds of the CURL connection
. This timeout is the time
2982 that CURL waits
for a response from the remote server to get the size of the
2983 image to be downloaded
. If not set
, the
default timeout of
5 seconds is used
.
2986 Note that when passing options to qemu explicitly
, @option
{driver
} is the value
2989 Example
: boot from a remote Fedora
20 live ISO image
2991 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
2993 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
2996 Example
: boot from a remote Fedora
20 cloud image
using a local overlay
for
2997 writes
, copy
-on
-read
, and a readahead of
64k
2999 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
3001 qemu
-system
-x86_64
-drive file
=/tmp
/Fedora
-x86_64
-20-20131211.1-sda
.qcow2
,copy
-on
-read
=on
3004 Example
: boot from an image stored on a VMware vSphere server with a self
-signed
3005 certificate
using a local overlay
for writes
, a readahead of
64k and a timeout
3008 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
3010 qemu
-system
-x86_64
-drive file
=/tmp
/test
.qcow2
3018 DEFHEADING(Bluetooth(R
) options
)
3023 DEF("bt", HAS_ARG
, QEMU_OPTION_bt
, \
3024 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \
3025 "-bt hci,host[:id]\n" \
3026 " use host's HCI with the given name\n" \
3027 "-bt hci[,vlan=n]\n" \
3028 " emulate a standard HCI in virtual scatternet 'n'\n" \
3029 "-bt vhci[,vlan=n]\n" \
3030 " add host computer to virtual scatternet 'n' using VHCI\n" \
3031 "-bt device:dev[,vlan=n]\n" \
3032 " emulate a bluetooth device 'dev' in scatternet 'n'\n",
3037 Defines the
function of the corresponding Bluetooth HCI
. -bt options
3038 are matched with the HCIs present
in the chosen machine type
. For
3039 example when emulating a machine with only one HCI built into it
, only
3040 the first @code
{-bt hci
[...]} option is valid and defines the HCI
's
3041 logic. The Transport Layer is decided by the machine type. Currently
3042 the machines @code{n800} and @code{n810} have one HCI and all other
3046 The following three types are recognized:
3050 (default) The corresponding Bluetooth HCI assumes no internal logic
3051 and will not respond to any HCI commands or emit events.
3053 @item -bt hci,host[:@var{id}]
3054 (@code{bluez} only) The corresponding HCI passes commands / events
3055 to / from the physical HCI identified by the name @var{id} (default:
3056 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
3057 capable systems like Linux.
3059 @item -bt hci[,vlan=@var{n}]
3060 Add a virtual, standard HCI that will participate in the Bluetooth
3061 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
3062 VLANs, devices inside a bluetooth network @var{n} can only communicate
3063 with other devices in the same network (scatternet).
3066 @item -bt vhci[,vlan=@var{n}]
3067 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
3068 to the host bluetooth stack instead of to the emulated target. This
3069 allows the host and target machines to participate in a common scatternet
3070 and communicate. Requires the Linux @code{vhci} driver installed. Can
3071 be used as following:
3074 qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
3077 @item -bt device:@var{dev}[,vlan=@var{n}]
3078 Emulate a bluetooth device @var{dev} and place it in network @var{n}
3079 (default @code{0}). QEMU can only emulate one type of bluetooth devices
3084 Virtual wireless keyboard implementing the HIDP bluetooth profile.
3094 DEFHEADING(TPM device options)
3096 DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
3097 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
3098 " use path to provide path to a character device; default is /dev/tpm0\n"
3099 " use cancel-path to provide path to TPM's cancel sysfs entry
; if\n"
3100 " not provided it will be searched
for in /sys
/class/misc
/tpm?
/device
\n",
3104 The general form of a TPM device option is:
3107 @item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
3109 Backend type must be:
3110 @option{passthrough}.
3112 The specific backend type will determine the applicable options.
3113 The @code{-tpmdev} option creates the TPM backend and requires a
3114 @code{-device} option that specifies the TPM frontend interface model.
3116 Options to each backend are described below.
3118 Use 'help' to print all available TPM backend types.
3123 @item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path}
3125 (Linux-host only) Enable access to the host's TPM using the passthrough
3128 @option{path} specifies the path to the host's TPM device, i.e., on
3129 a Linux host this would be @code{/dev/tpm0}.
3130 @option{path} is optional and by default @code{/dev/tpm0} is used.
3132 @option{cancel-path} specifies the path to the host TPM device's sysfs
3133 entry allowing for cancellation of an ongoing TPM command.
3134 @option{cancel-path} is optional and by default QEMU will search for the
3137 Some notes about using the host's TPM with the passthrough driver:
3139 The TPM device accessed by the passthrough driver must not be
3140 used by any other application on the host.
3142 Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
3143 the VM's firmware (BIOS/UEFI) will not be able to initialize the
3144 TPM again and may therefore not show a TPM-specific menu that would
3145 otherwise allow the user to configure the TPM, e.g., allow the user to
3146 enable/disable or activate/deactivate the TPM.
3147 Further, if TPM ownership is released from within a VM then the host's TPM
3148 will get disabled and deactivated. To enable and activate the
3149 TPM again afterwards, the host has to be rebooted and the user is
3150 required to enter the firmware's menu to enable and activate the TPM.
3151 If the TPM is left disabled and/or deactivated most TPM commands will fail.
3153 To create a passthrough TPM use the following two options:
3155 -tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
3157 Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
3158 @code{tpmdev=tpm0} in the device option.
3168 DEFHEADING(Linux/Multiboot boot specific)
3171 When using these options, you can use a given Linux or Multiboot
3172 kernel without installing it in the disk image. It can be useful
3173 for easier testing of various kernels.
3178 DEF("kernel
", HAS_ARG, QEMU_OPTION_kernel, \
3179 "-kernel bzImage use
'bzImage' as kernel image
\n", QEMU_ARCH_ALL)
3181 @item -kernel @var{bzImage}
3183 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
3184 or in multiboot format.
3187 DEF("append
", HAS_ARG, QEMU_OPTION_append, \
3188 "-append cmdline use
'cmdline' as kernel command line
\n", QEMU_ARCH_ALL)
3190 @item -append @var{cmdline}
3192 Use @var{cmdline} as kernel command line
3195 DEF("initrd
", HAS_ARG, QEMU_OPTION_initrd, \
3196 "-initrd file use
'file' as initial ram disk
\n", QEMU_ARCH_ALL)
3198 @item -initrd @var{file}
3200 Use @var{file} as initial ram disk.
3202 @item -initrd "@
var{file1
} arg
=foo
,@
var{file2
}"
3204 This syntax is only available with multiboot.
3206 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
3210 DEF("dtb
", HAS_ARG, QEMU_OPTION_dtb, \
3211 "-dtb file use
'file' as device tree image
\n", QEMU_ARCH_ALL)
3213 @item -dtb @var{file}
3215 Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
3224 DEFHEADING(Debug/Expert options)
3229 DEF("fw_cfg
", HAS_ARG, QEMU_OPTION_fwcfg,
3230 "-fw_cfg
[name
=]<name
>,file
=<file
>\n"
3231 " add named fw_cfg entry with contents from file
\n"
3232 "-fw_cfg
[name
=]<name
>,string
=<str
>\n"
3233 " add named fw_cfg entry with contents from string
\n",
3237 @item -fw_cfg [name=]@var{name},file=@var{file}
3239 Add named fw_cfg entry with contents from file @var{file}.
3241 @item -fw_cfg [name=]@var{name},string=@var{str}
3242 Add named fw_cfg entry with contents from string @var{str}.
3244 The terminating NUL character of the contents of @var{str} will not be
3245 included as part of the fw_cfg item data. To insert contents with
3246 embedded NUL characters, you have to use the @var{file} parameter.
3248 The fw_cfg entries are passed by QEMU through to the guest.
3252 -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin
3254 creates an fw_cfg entry named opt/com.mycompany/blob with contents
3259 DEF("serial
", HAS_ARG, QEMU_OPTION_serial, \
3260 "-serial dev redirect the serial port to char device
'dev'\n",
3263 @item -serial @var{dev}
3265 Redirect the virtual serial port to host character device
3266 @var{dev}. The default device is @code{vc} in graphical mode and
3267 @code{stdio} in non graphical mode.
3269 This option can be used several times to simulate up to 4 serial
3272 Use @code{-serial none} to disable all serial ports.
3274 Available character devices are:
3276 @item vc[:@var{W}x@var{H}]
3277 Virtual console. Optionally, a width and height can be given in pixel with
3281 It is also possible to specify width or height in characters:
3286 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
3288 No device is allocated.
3291 @item chardev:@var{id}
3292 Use a named character device defined with the @code{-chardev} option.
3294 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
3295 parameters are set according to the emulated ones.
3296 @item /dev/parport@var{N}
3297 [Linux only, parallel port only] Use host parallel port
3298 @var{N}. Currently SPP and EPP parallel port features can be used.
3299 @item file:@var{filename}
3300 Write output to @var{filename}. No character can be read.
3302 [Unix only] standard input/output
3303 @item pipe:@var{filename}
3304 name pipe @var{filename}
3306 [Windows only] Use host serial port @var{n}
3307 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
3308 This implements UDP Net Console.
3309 When @var{remote_host} or @var{src_ip} are not specified
3310 they default to @code{0.0.0.0}.
3311 When not using a specified @var{src_port} a random port is automatically chosen.
3313 If you just want a simple readonly console you can use @code{netcat} or
3314 @code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
3315 @code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
3316 will appear in the netconsole session.
3318 If you plan to send characters back via netconsole or you want to stop
3319 and start QEMU a lot of times, you should have QEMU use the same
3320 source port each time by using something like @code{-serial
3321 udp::4555@@:4556} to QEMU. Another approach is to use a patched
3322 version of netcat which can listen to a TCP port and send and receive
3323 characters via udp. If you have a patched version of netcat which
3324 activates telnet remote echo and single char transfer, then you can
3325 use the following options to set up a netcat redirector to allow
3326 telnet on port 5555 to access the QEMU port.
3329 -serial udp::4555@@:4556
3330 @item netcat options:
3331 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
3332 @item telnet options:
3336 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}]
3337 The TCP Net Console has two modes of operation. It can send the serial
3338 I/O to a location or wait for a connection from a location. By default
3339 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
3340 the @var{server} option QEMU will wait for a client socket application
3341 to connect to the port before continuing, unless the @code{nowait}
3342 option was specified. The @code{nodelay} option disables the Nagle buffering
3343 algorithm. The @code{reconnect} option only applies if @var{noserver} is
3344 set, if the connection goes down it will attempt to reconnect at the
3345 given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only
3346 one TCP connection at a time is accepted. You can use @code{telnet} to
3347 connect to the corresponding character device.
3349 @item Example to send tcp console to 192.168.0.2 port 4444
3350 -serial tcp:192.168.0.2:4444
3351 @item Example to listen and wait on port 4444 for connection
3352 -serial tcp::4444,server
3353 @item Example to not wait and listen on ip 192.168.0.100 port 4444
3354 -serial tcp:192.168.0.100:4444,server,nowait
3357 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
3358 The telnet protocol is used instead of raw tcp sockets. The options
3359 work the same as if you had specified @code{-serial tcp}. The
3360 difference is that the port acts like a telnet server or client using
3361 telnet option negotiation. This will also allow you to send the
3362 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
3363 sequence. Typically in unix telnet you do it with Control-] and then
3364 type "send
break" followed by pressing the enter key.
3366 @item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}]
3367 A unix domain socket is used instead of a tcp socket. The option works the
3368 same as if you had specified @code{-serial tcp} except the unix domain socket
3369 @var{path} is used for connections.
3371 @item mon:@var{dev_string}
3372 This is a special option to allow the monitor to be multiplexed onto
3373 another serial port. The monitor is accessed with key sequence of
3374 @key{Control-a} and then pressing @key{c}.
3375 @var{dev_string} should be any one of the serial devices specified
3376 above. An example to multiplex the monitor onto a telnet server
3377 listening on port 4444 would be:
3379 @item -serial mon:telnet::4444,server,nowait
3381 When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
3382 QEMU any more but will be passed to the guest instead.
3385 Braille device. This will use BrlAPI to display the braille output on a real
3389 Three button serial mouse. Configure the guest to use Microsoft protocol.
3393 DEF("parallel
", HAS_ARG, QEMU_OPTION_parallel, \
3394 "-parallel dev redirect the parallel port to char device
'dev'\n",
3397 @item -parallel @var{dev}
3399 Redirect the virtual parallel port to host device @var{dev} (same
3400 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
3401 be used to use hardware devices connected on the corresponding host
3404 This option can be used several times to simulate up to 3 parallel
3407 Use @code{-parallel none} to disable all parallel ports.
3410 DEF("monitor
", HAS_ARG, QEMU_OPTION_monitor, \
3411 "-monitor dev redirect the monitor to char device
'dev'\n",
3414 @item -monitor @var{dev}
3416 Redirect the monitor to host device @var{dev} (same devices as the
3418 The default device is @code{vc} in graphical mode and @code{stdio} in
3420 Use @code{-monitor none} to disable the default monitor.
3422 DEF("qmp
", HAS_ARG, QEMU_OPTION_qmp, \
3423 "-qmp dev like
-monitor but opens
in 'control' mode
\n",
3426 @item -qmp @var{dev}
3428 Like -monitor but opens in 'control' mode.
3430 DEF("qmp
-pretty
", HAS_ARG, QEMU_OPTION_qmp_pretty, \
3431 "-qmp
-pretty dev like
-qmp but uses pretty JSON formatting
\n",
3434 @item -qmp-pretty @var{dev}
3436 Like -qmp but uses pretty JSON formatting.
3439 DEF("mon
", HAS_ARG, QEMU_OPTION_mon, \
3440 "-mon
[chardev
=]name
[,mode
=readline|control
]\n", QEMU_ARCH_ALL)
3442 @item -mon [chardev=]name[,mode=readline|control]
3444 Setup monitor on chardev @var{name}.
3447 DEF("debugcon
", HAS_ARG, QEMU_OPTION_debugcon, \
3448 "-debugcon dev redirect the debug console to char device
'dev'\n",
3451 @item -debugcon @var{dev}
3453 Redirect the debug console to host device @var{dev} (same devices as the
3454 serial port). The debug console is an I/O port which is typically port
3455 0xe9; writing to that I/O port sends output to this device.
3456 The default device is @code{vc} in graphical mode and @code{stdio} in
3460 DEF("pidfile
", HAS_ARG, QEMU_OPTION_pidfile, \
3461 "-pidfile file write PID to
'file'\n", QEMU_ARCH_ALL)
3463 @item -pidfile @var{file}
3465 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
3469 DEF("singlestep
", 0, QEMU_OPTION_singlestep, \
3470 "-singlestep always run
in singlestep mode
\n", QEMU_ARCH_ALL)
3474 Run the emulation in single step mode.
3477 DEF("S
", 0, QEMU_OPTION_S, \
3478 "-S freeze CPU at
startup (use
'c' to start execution
)\n",
3483 Do not start CPU at startup (you must type 'c' in the monitor).
3486 DEF("realtime
", HAS_ARG, QEMU_OPTION_realtime,
3487 "-realtime
[mlock
=on|off
]\n"
3488 " run qemu with realtime features
\n"
3489 " mlock
=on|off controls mlock
support (default: on
)\n",
3492 @item -realtime mlock=on|off
3494 Run qemu with realtime features.
3495 mlocking qemu and guest memory can be enabled via @option{mlock=on}
3496 (enabled by default).
3499 DEF("gdb
", HAS_ARG, QEMU_OPTION_gdb, \
3500 "-gdb dev wait
for gdb connection on
'dev'\n", QEMU_ARCH_ALL)
3502 @item -gdb @var{dev}
3504 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
3505 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
3506 stdio are reasonable use case. The latter is allowing to start QEMU from
3507 within gdb and establish the connection via a pipe:
3509 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
3513 DEF("s
", 0, QEMU_OPTION_s, \
3514 "-s shorthand
for -gdb tcp
::" DEFAULT_GDBSTUB_PORT "\n",
3519 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
3520 (@pxref{gdb_usage}).
3523 DEF("d
", HAS_ARG, QEMU_OPTION_d, \
3524 "-d item1
,... enable logging of specified
items (use
'-d help' for a list of log items
)\n",
3527 @item -d @var{item1}[,...]
3529 Enable logging of specified items. Use '-d help' for a list of log items.
3532 DEF("D
", HAS_ARG, QEMU_OPTION_D, \
3533 "-D logfile output log to
logfile (default stderr
)\n",
3536 @item -D @var{logfile}
3538 Output log in @var{logfile} instead of to stderr
3541 DEF("dfilter
", HAS_ARG, QEMU_OPTION_DFILTER, \
3542 "-dfilter range
,.. filter debug output to range of
addresses (useful
for -d cpu
,exec
,etc
..)\n",
3545 @item -dfilter @var{range1}[,...]
3547 Filter debug output to that relevant to a range of target addresses. The filter
3548 spec can be either @var{start}+@var{size}, @var{start}-@var{size} or
3549 @var{start}..@var{end} where @var{start} @var{end} and @var{size} are the
3550 addresses and sizes required. For example:
3552 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000
3554 Will dump output for any code in the 0x1000 sized block starting at 0x8000 and
3555 the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized
3556 block starting at 0xffffffc00005f000.
3559 DEF("L
", HAS_ARG, QEMU_OPTION_L, \
3560 "-L path set the directory
for the BIOS
, VGA BIOS and keymaps
\n",
3565 Set the directory for the BIOS, VGA BIOS and keymaps.
3567 To list all the data directories, use @code{-L help}.
3570 DEF("bios
", HAS_ARG, QEMU_OPTION_bios, \
3571 "-bios file set the filename
for the BIOS
\n", QEMU_ARCH_ALL)
3573 @item -bios @var{file}
3575 Set the filename for the BIOS.
3578 DEF("enable
-kvm
", 0, QEMU_OPTION_enable_kvm, \
3579 "-enable
-kvm enable KVM full virtualization support
\n", QEMU_ARCH_ALL)
3583 Enable KVM full virtualization support. This option is only available
3584 if KVM support is enabled when compiling.
3587 DEF("enable
-hax
", 0, QEMU_OPTION_enable_hax, \
3588 "-enable
-hax enable HAX virtualization support
\n", QEMU_ARCH_I386)
3592 Enable HAX (Hardware-based Acceleration eXecution) support. This option
3593 is only available if HAX support is enabled when compiling. HAX is only
3594 applicable to MAC and Windows platform, and thus does not conflict with
3598 DEF("xen
-domid
", HAS_ARG, QEMU_OPTION_xen_domid,
3599 "-xen
-domid id specify xen guest domain id
\n", QEMU_ARCH_ALL)
3600 DEF("xen
-create
", 0, QEMU_OPTION_xen_create,
3601 "-xen
-create create domain
using xen hypercalls
, bypassing xend
\n"
3602 " warning
: should not be used when xend is
in use
\n",
3604 DEF("xen
-attach
", 0, QEMU_OPTION_xen_attach,
3605 "-xen
-attach attach to existing xen domain
\n"
3606 " xend will use
this when starting QEMU
\n",
3608 DEF("xen
-domid
-restrict
", 0, QEMU_OPTION_xen_domid_restrict,
3609 "-xen
-domid
-restrict restrict set of available xen operations
\n"
3610 " to specified domain id
. (Does not affect
\n"
3611 " xenpv machine type
).\n",
3614 @item -xen-domid @var{id}
3616 Specify xen guest domain @var{id} (XEN only).
3619 Create domain using xen hypercalls, bypassing xend.
3620 Warning: should not be used when xend is in use (XEN only).
3623 Attach to existing xen domain.
3624 xend will use this when starting QEMU (XEN only).
3625 @findex -xen-domid-restrict
3626 Restrict set of available xen operations to specified domain id (XEN only).
3629 DEF("no
-reboot
", 0, QEMU_OPTION_no_reboot, \
3630 "-no
-reboot exit instead of rebooting
\n", QEMU_ARCH_ALL)
3634 Exit instead of rebooting.
3637 DEF("no
-shutdown
", 0, QEMU_OPTION_no_shutdown, \
3638 "-no
-shutdown stop before shutdown
\n", QEMU_ARCH_ALL)
3641 @findex -no-shutdown
3642 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
3643 This allows for instance switching to monitor to commit changes to the
3647 DEF("loadvm
", HAS_ARG, QEMU_OPTION_loadvm, \
3648 "-loadvm
[tag|id
]\n" \
3649 " start right away with a saved
state (loadvm
in monitor
)\n",
3652 @item -loadvm @var{file}
3654 Start right away with a saved state (@code{loadvm} in monitor)
3658 DEF("daemonize
", 0, QEMU_OPTION_daemonize, \
3659 "-daemonize daemonize QEMU after initializing
\n", QEMU_ARCH_ALL)
3664 Daemonize the QEMU process after initialization. QEMU will not detach from
3665 standard IO until it is ready to receive connections on any of its devices.
3666 This option is a useful way for external programs to launch QEMU without having
3667 to cope with initialization race conditions.
3670 DEF("option
-rom
", HAS_ARG, QEMU_OPTION_option_rom, \
3671 "-option
-rom rom load a file
, rom
, into the option ROM space
\n",
3674 @item -option-rom @var{file}
3676 Load the contents of @var{file} as an option ROM.
3677 This option is useful to load things like EtherBoot.
3680 HXCOMM Silently ignored for compatibility
3681 DEF("clock
", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL)
3683 HXCOMM Options deprecated by -rtc
3684 DEF("localtime
", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
3685 DEF("startdate
", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
3687 DEF("rtc
", HAS_ARG, QEMU_OPTION_rtc, \
3688 "-rtc
[base
=utc|localtime|date
][,clock
=host|rt|vm
][,driftfix
=none|slew
]\n" \
3689 " set the RTC base and clock
, enable drift fix
for clock
ticks (x86 only
)\n",
3694 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
3696 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
3697 UTC or local time, respectively. @code{localtime} is required for correct date in
3698 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
3699 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
3701 By default the RTC is driven by the host system time. This allows using of the
3702 RTC as accurate reference clock inside the guest, specifically if the host
3703 time is smoothly following an accurate external reference clock, e.g. via NTP.
3704 If you want to isolate the guest time from the host, you can set @option{clock}
3705 to @code{rt} instead. To even prevent it from progressing during suspension,
3706 you can set it to @code{vm}.
3708 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
3709 specifically with Windows' ACPI HAL. This option will try to figure out how
3710 many timer interrupts were not processed by the Windows guest and will
3714 DEF("icount
", HAS_ARG, QEMU_OPTION_icount, \
3715 "-icount
[shift
=N|auto
][,align
=on|off
][,sleep
=on|off
,rr
=record|replay
,rrfile
=<filename
>,rrsnapshot
=<snapshot
>]\n" \
3716 " enable virtual instruction counter with
2^N clock ticks per
\n" \
3717 " instruction
, enable aligning the host and virtual clocks
\n" \
3718 " or disable real time cpu sleeping
\n", QEMU_ARCH_ALL)
3720 @item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}]
3722 Enable virtual instruction counter. The virtual cpu will execute one
3723 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
3724 then the virtual cpu speed will be automatically adjusted to keep virtual
3725 time within a few seconds of real time.
3727 When the virtual cpu is sleeping, the virtual time will advance at default
3728 speed unless @option{sleep=on|off} is specified.
3729 With @option{sleep=on|off}, the virtual time will jump to the next timer deadline
3730 instantly whenever the virtual cpu goes to sleep mode and will not advance
3731 if no timer is enabled. This behavior give deterministic execution times from
3732 the guest point of view.
3734 Note that while this option can give deterministic behavior, it does not
3735 provide cycle accurate emulation. Modern CPUs contain superscalar out of
3736 order cores with complex cache hierarchies. The number of instructions
3737 executed often has little or no correlation with actual performance.
3739 @option{align=on} will activate the delay algorithm which will try
3740 to synchronise the host clock and the virtual clock. The goal is to
3741 have a guest running at the real frequency imposed by the shift option.
3742 Whenever the guest clock is behind the host clock and if
3743 @option{align=on} is specified then we print a message to the user
3744 to inform about the delay.
3745 Currently this option does not work when @option{shift} is @code{auto}.
3746 Note: The sync algorithm will work for those shift values for which
3747 the guest clock runs ahead of the host clock. Typically this happens
3748 when the shift value is high (how high depends on the host machine).
3750 When @option{rr} option is specified deterministic record/replay is enabled.
3751 Replay log is written into @var{filename} file in record mode and
3752 read from this file in replay mode.
3754 Option rrsnapshot is used to create new vm snapshot named @var{snapshot}
3755 at the start of execution recording. In replay mode this option is used
3756 to load the initial VM state.
3759 DEF("watchdog
", HAS_ARG, QEMU_OPTION_watchdog, \
3760 "-watchdog model
\n" \
3761 " enable virtual hardware watchdog
[default=none
]\n",
3764 @item -watchdog @var{model}
3766 Create a virtual hardware watchdog device. Once enabled (by a guest
3767 action), the watchdog must be periodically polled by an agent inside
3768 the guest or else the guest will be restarted. Choose a model for
3769 which your guest has drivers.
3771 The @var{model} is the model of hardware watchdog to emulate. Use
3772 @code{-watchdog help} to list available hardware models. Only one
3773 watchdog can be enabled for a guest.
3775 The following models may be available:
3778 iBASE 700 is a very simple ISA watchdog with a single timer.
3780 Intel 6300ESB I/O controller hub is a much more featureful PCI-based
3781 dual-timer watchdog.
3783 A virtual watchdog for s390x backed by the diagnose 288 hypercall
3784 (currently KVM only).
3788 DEF("watchdog
-action
", HAS_ARG, QEMU_OPTION_watchdog_action, \
3789 "-watchdog
-action reset|shutdown|poweroff|pause|debug|none
\n" \
3790 " action when watchdog fires
[default=reset
]\n",
3793 @item -watchdog-action @var{action}
3794 @findex -watchdog-action
3796 The @var{action} controls what QEMU will do when the watchdog timer
3799 @code{reset} (forcefully reset the guest).
3800 Other possible actions are:
3801 @code{shutdown} (attempt to gracefully shutdown the guest),
3802 @code{poweroff} (forcefully poweroff the guest),
3803 @code{pause} (pause the guest),
3804 @code{debug} (print a debug message and continue), or
3805 @code{none} (do nothing).
3807 Note that the @code{shutdown} action requires that the guest responds
3808 to ACPI signals, which it may not be able to do in the sort of
3809 situations where the watchdog would have expired, and thus
3810 @code{-watchdog-action shutdown} is not recommended for production use.
3815 @item -watchdog i6300esb -watchdog-action pause
3816 @itemx -watchdog ib700
3820 DEF("echr
", HAS_ARG, QEMU_OPTION_echr, \
3821 "-echr chr set terminal escape character instead of ctrl
-a
\n",
3825 @item -echr @var{numeric_ascii_value}
3827 Change the escape character used for switching to the monitor when using
3828 monitor and serial sharing. The default is @code{0x01} when using the
3829 @code{-nographic} option. @code{0x01} is equal to pressing
3830 @code{Control-a}. You can select a different character from the ascii
3831 control keys where 1 through 26 map to Control-a through Control-z. For
3832 instance you could use the either of the following to change the escape
3833 character to Control-t.
3840 DEF("virtioconsole
", HAS_ARG, QEMU_OPTION_virtiocon, \
3841 "-virtioconsole c
\n" \
3842 " set virtio console
\n", QEMU_ARCH_ALL)
3844 @item -virtioconsole @var{c}
3845 @findex -virtioconsole
3848 This option is maintained for backward compatibility.
3850 Please use @code{-device virtconsole} for the new way of invocation.
3853 DEF("show
-cursor
", 0, QEMU_OPTION_show_cursor, \
3854 "-show
-cursor show cursor
\n", QEMU_ARCH_ALL)
3857 @findex -show-cursor
3861 DEF("tb
-size
", HAS_ARG, QEMU_OPTION_tb_size, \
3862 "-tb
-size n set TB size
\n", QEMU_ARCH_ALL)
3864 @item -tb-size @var{n}
3869 DEF("incoming
", HAS_ARG, QEMU_OPTION_incoming, \
3870 "-incoming tcp
:[host
]:port
[,to
=maxport
][,ipv4
][,ipv6
]\n" \
3871 "-incoming rdma
:host
:port
[,ipv4
][,ipv6
]\n" \
3872 "-incoming unix
:socketpath
\n" \
3873 " prepare
for incoming migration
, listen on
\n" \
3874 " specified protocol and socket address
\n" \
3875 "-incoming fd
:fd
\n" \
3876 "-incoming exec
:cmdline
\n" \
3877 " accept incoming migration on given file descriptor
\n" \
3878 " or from given external command
\n" \
3879 "-incoming defer
\n" \
3880 " wait
for the URI to be specified via migrate_incoming
\n",
3883 @item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6]
3884 @itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6]
3886 Prepare for incoming migration, listen on a given tcp port.
3888 @item -incoming unix:@var{socketpath}
3889 Prepare for incoming migration, listen on a given unix socket.
3891 @item -incoming fd:@var{fd}
3892 Accept incoming migration from a given filedescriptor.
3894 @item -incoming exec:@var{cmdline}
3895 Accept incoming migration as an output from specified external command.
3897 @item -incoming defer
3898 Wait for the URI to be specified via migrate_incoming. The monitor can
3899 be used to change settings (such as migration parameters) prior to issuing
3900 the migrate_incoming to allow the migration to begin.
3903 DEF("only
-migratable
", 0, QEMU_OPTION_only_migratable, \
3904 "-only
-migratable allow only migratable devices
\n", QEMU_ARCH_ALL)
3906 @item -only-migratable
3907 @findex -only-migratable
3908 Only allow migratable devices. Devices will not be allowed to enter an
3912 DEF("nodefaults
", 0, QEMU_OPTION_nodefaults, \
3913 "-nodefaults don
't create default devices\n", QEMU_ARCH_ALL)
3917 Don't create
default devices
. Normally
, QEMU sets the
default devices like serial
3918 port
, parallel port
, virtual console
, monitor device
, VGA adapter
, floppy and
3919 CD
-ROM drive and others
. The @code
{-nodefaults
} option will disable all those
3924 DEF("chroot", HAS_ARG
, QEMU_OPTION_chroot
, \
3925 "-chroot dir chroot to dir just before starting the VM\n",
3929 @item
-chroot @
var{dir
}
3931 Immediately before starting guest execution
, chroot to the specified
3932 directory
. Especially useful
in combination with
-runas
.
3936 DEF("runas", HAS_ARG
, QEMU_OPTION_runas
, \
3937 "-runas user change to user id user just before starting the VM\n",
3941 @item
-runas @
var{user
}
3943 Immediately before starting guest execution
, drop root privileges
, switching
3944 to the specified user
.
3947 DEF("prom-env", HAS_ARG
, QEMU_OPTION_prom_env
,
3948 "-prom-env variable=value\n"
3949 " set OpenBIOS nvram variables\n",
3950 QEMU_ARCH_PPC | QEMU_ARCH_SPARC
)
3952 @item
-prom
-env @
var{variable
}=@
var{value
}
3954 Set OpenBIOS nvram @
var{variable
} to given @
var{value
} (PPC
, SPARC only
).
3956 DEF("semihosting", 0, QEMU_OPTION_semihosting
,
3957 "-semihosting semihosting mode\n",
3958 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3962 @findex
-semihosting
3963 Enable semihosting
mode (ARM
, M68K
, Xtensa
, MIPS only
).
3965 DEF("semihosting-config", HAS_ARG
, QEMU_OPTION_semihosting_config
,
3966 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \
3967 " semihosting configuration\n",
3968 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3971 @item
-semihosting
-config
[enable
=on|off
][,target
=native|gdb|auto
][,arg
=str
[,...]]
3972 @findex
-semihosting
-config
3973 Enable and configure
semihosting (ARM
, M68K
, Xtensa
, MIPS only
).
3975 @item target
=@code
{native|gdb|auto
}
3976 Defines where the semihosting calls will be addressed
, to
QEMU (@code
{native
})
3977 or to
GDB (@code
{gdb
}). The
default is @code
{auto
}, which means @code
{gdb
}
3978 during debug sessions and @code
{native
} otherwise
.
3979 @item arg
=@
var{str1
},arg
=@
var{str2
},...
3980 Allows the user to pass input arguments
, and can be used multiple times to build
3981 up a list
. The old
-style @code
{-kernel
}/@code
{-append
} method of passing a
3982 command line is still supported
for backward compatibility
. If both the
3983 @code
{--semihosting
-config arg
} and the @code
{-kernel
}/@code
{-append
} are
3984 specified
, the former is passed to semihosting as it always takes precedence
.
3987 DEF("old-param", 0, QEMU_OPTION_old_param
,
3988 "-old-param old param mode\n", QEMU_ARCH_ARM
)
3991 @findex
-old
-param (ARM
)
3992 Old param
mode (ARM only
).
3995 DEF("sandbox", HAS_ARG
, QEMU_OPTION_sandbox
, \
3996 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n",
3999 @item
-sandbox @
var{arg
}
4001 Enable Seccomp mode
2 system call filter
. 'on' will enable syscall filtering and
'off' will
4002 disable it
. The
default is
'off'.
4005 DEF("readconfig", HAS_ARG
, QEMU_OPTION_readconfig
,
4006 "-readconfig <file>\n", QEMU_ARCH_ALL
)
4008 @item
-readconfig @
var{file
}
4010 Read device configuration from @
var{file
}. This approach is useful when you want to spawn
4011 QEMU process with many command line options but you don
't want to exceed the command line
4014 DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
4015 "-writeconfig <file>\n"
4016 " read/write config file\n", QEMU_ARCH_ALL)
4018 @item -writeconfig @var{file}
4019 @findex -writeconfig
4020 Write device configuration to @var{file}. The @var{file} can be either filename to save
4021 command line and device configuration into file or dash @code{-}) character to print the
4022 output to stdout. This can be later used as input file for @code{-readconfig} option.
4024 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig,
4026 " do not load default config files at startup\n",
4030 @findex -nodefconfig
4031 Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
4032 The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
4034 DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
4036 " do not load user-provided config files at startup\n",
4039 @item -no-user-config
4040 @findex -no-user-config
4041 The @code{-no-user-config} option makes QEMU not load any of the user-provided
4042 config files on @var{sysconfdir}, but won't make it skip the QEMU
-provided config
4043 files from @
var{datadir
}.
4045 DEF("trace", HAS_ARG
, QEMU_OPTION_trace
,
4046 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
4047 " specify tracing options\n",
4050 HXCOMM This line is not accurate
, as some sub
-options are backend
-specific but
4051 HXCOMM HX does not support conditional compilation of text
.
4052 @item
-trace [[enable
=]@
var{pattern
}][,events
=@
var{file
}][,file
=@
var{file
}]
4054 @include qemu
-option
-trace.texi
4058 DEF("qtest", HAS_ARG
, QEMU_OPTION_qtest
, "", QEMU_ARCH_ALL
)
4059 DEF("qtest-log", HAS_ARG
, QEMU_OPTION_qtest_log
, "", QEMU_ARCH_ALL
)
4062 DEF("enable-fips", 0, QEMU_OPTION_enablefips
,
4063 "-enable-fips enable FIPS 140-2 compliance\n",
4068 @findex
-enable
-fips
4069 Enable FIPS
140-2 compliance mode
.
4072 HXCOMM Deprecated by
-machine accel
=tcg property
4073 DEF("no-kvm", 0, QEMU_OPTION_no_kvm
, "", QEMU_ARCH_I386
)
4075 HXCOMM Deprecated by kvm
-pit driver properties
4076 DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection
,
4079 HXCOMM
Deprecated (ignored
)
4080 DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit
, "", QEMU_ARCH_I386
)
4082 HXCOMM Deprecated by
-machine kernel_irqchip
=on|off property
4083 DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip
, "", QEMU_ARCH_I386
)
4085 HXCOMM
Deprecated (ignored
)
4086 DEF("tdf", 0, QEMU_OPTION_tdf
,"", QEMU_ARCH_ALL
)
4088 DEF("msg", HAS_ARG
, QEMU_OPTION_msg
,
4089 "-msg timestamp[=on|off]\n"
4090 " change the format of messages\n"
4091 " on|off controls leading timestamps (default:on)\n",
4094 @item
-msg timestamp
[=on|off
]
4096 prepend a timestamp to each log message
.(default:on
)
4099 DEF("dump-vmstate", HAS_ARG
, QEMU_OPTION_dump_vmstate
,
4100 "-dump-vmstate <file>\n"
4101 " Output vmstate information in JSON format to file.\n"
4102 " Use the scripts/vmstate-static-checker.py file to\n"
4103 " check for possible regressions in migration code\n"
4104 " by comparing two such vmstate dumps.\n",
4107 @item
-dump
-vmstate @
var{file
}
4108 @findex
-dump
-vmstate
4109 Dump json
-encoded vmstate information
for current machine type to file
4117 DEFHEADING(Generic object creation
)
4122 DEF("object", HAS_ARG
, QEMU_OPTION_object
,
4123 "-object TYPENAME[,PROP1=VALUE1,...]\n"
4124 " create a new object of type TYPENAME setting properties\n"
4125 " in the order they are specified. Note that the 'id'\n"
4126 " property must be set. These objects are placed in the\n"
4127 " '/objects' path.\n",
4130 @item
-object @
var{typename
}[,@
var{prop1
}=@
var{value1
},...]
4132 Create a
new object of type @
var{typename
} setting properties
4133 in the order they are specified
. Note that the
'id'
4134 property must be set
. These objects are placed
in the
4139 @item
-object memory
-backend
-file
,id
=@
var{id
},size
=@
var{size
},mem
-path
=@
var{dir
},share
=@
var{on|off
}
4141 Creates a memory file backend object
, which can be used to back
4142 the guest RAM with huge pages
. The @option
{id
} parameter is a
4143 unique ID that will be used to reference
this memory region
4144 when configuring the @option
{-numa
} argument
. The @option
{size
}
4145 option provides the size of the memory region
, and accepts
4146 common suffixes
, eg @option
{500M
}. The @option
{mem
-path
} provides
4147 the path to either a shared memory or huge page filesystem mount
.
4148 The @option
{share
} boolean option determines whether the memory
4149 region is marked as
private to QEMU
, or shared
. The latter allows
4150 a co
-operating external process to access the QEMU memory region
.
4152 @item
-object rng
-random
,id
=@
var{id
},filename
=@
var{/dev
/random
}
4154 Creates a random number generator backend which obtains entropy from
4155 a device on the host
. The @option
{id
} parameter is a unique ID that
4156 will be used to reference
this entropy backend from the @option
{virtio
-rng
}
4157 device
. The @option
{filename
} parameter specifies which file to obtain
4158 entropy from and
if omitted defaults to @option
{/dev
/random
}.
4160 @item
-object rng
-egd
,id
=@
var{id
},chardev
=@
var{chardevid
}
4162 Creates a random number generator backend which obtains entropy from
4163 an external daemon running on the host
. The @option
{id
} parameter is
4164 a unique ID that will be used to reference
this entropy backend from
4165 the @option
{virtio
-rng
} device
. The @option
{chardev
} parameter is
4166 the unique ID of a character device backend that provides the connection
4169 @item
-object tls
-creds
-anon
,id
=@
var{id
},endpoint
=@
var{endpoint
},dir
=@
var{/path
/to
/cred
/dir
},verify
-peer
=@
var{on|off
}
4171 Creates a TLS anonymous credentials object
, which can be used to provide
4172 TLS support on network backends
. The @option
{id
} parameter is a unique
4173 ID which network backends will use to access the credentials
. The
4174 @option
{endpoint
} is either @option
{server
} or @option
{client
} depending
4175 on whether the QEMU network backend that uses the credentials will be
4176 acting as a client or as a server
. If @option
{verify
-peer
} is enabled
4177 (the
default) then once the handshake is completed
, the peer credentials
4178 will be verified
, though
this is a no
-op
for anonymous credentials
.
4180 The @
var{dir
} parameter tells QEMU where to find the credential
4181 files
. For server endpoints
, this directory may contain a file
4182 @
var{dh
-params
.pem
} providing diffie
-hellman parameters to use
4183 for the TLS server
. If the file is missing
, QEMU will generate
4184 a set of DH parameters at startup
. This is a computationally
4185 expensive operation that consumes random pool entropy
, so it is
4186 recommended that a persistent set of parameters be generated
4189 @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
}
4191 Creates a TLS anonymous credentials object
, which can be used to provide
4192 TLS support on network backends
. The @option
{id
} parameter is a unique
4193 ID which network backends will use to access the credentials
. The
4194 @option
{endpoint
} is either @option
{server
} or @option
{client
} depending
4195 on whether the QEMU network backend that uses the credentials will be
4196 acting as a client or as a server
. If @option
{verify
-peer
} is enabled
4197 (the
default) then once the handshake is completed
, the peer credentials
4198 will be verified
. With x509 certificates
, this implies that the clients
4199 must be provided with valid client certificates too
.
4201 The @
var{dir
} parameter tells QEMU where to find the credential
4202 files
. For server endpoints
, this directory may contain a file
4203 @
var{dh
-params
.pem
} providing diffie
-hellman parameters to use
4204 for the TLS server
. If the file is missing
, QEMU will generate
4205 a set of DH parameters at startup
. This is a computationally
4206 expensive operation that consumes random pool entropy
, so it is
4207 recommended that a persistent set of parameters be generated
4210 For x509 certificate credentials the directory will contain further files
4211 providing the x509 certificates
. The certificates must be stored
4212 in PEM format
, in filenames @
var{ca
-cert
.pem
}, @
var{ca
-crl
.pem
} (optional
),
4213 @
var{server
-cert
.pem
} (only servers
), @
var{server
-key
.pem
} (only servers
),
4214 @
var{client
-cert
.pem
} (only clients
), and @
var{client
-key
.pem
} (only clients
).
4216 For the @
var{server
-key
.pem
} and @
var{client
-key
.pem
} files which
4217 contain sensitive
private keys
, it is possible to use an encrypted
4218 version by providing the @
var{passwordid
} parameter
. This provides
4219 the ID of a previously created @code
{secret
} object containing the
4220 password
for decryption
.
4222 @item
-object filter
-buffer
,id
=@
var{id
},netdev
=@
var{netdevid
},interval
=@
var{t
}[,queue
=@
var{all|rx|tx
}][,status
=@
var{on|off
}]
4224 Interval @
var{t
} can
't be 0, this filter batches the packet delivery: all
4225 packets arriving in a given interval on netdev @var{netdevid} are delayed
4226 until the end of the interval. Interval is in microseconds.
4227 @option{status} is optional that indicate whether the netfilter is
4228 on (enabled) or off (disabled), the default status for netfilter will be 'on
'.
4230 queue @var{all|rx|tx} is an option that can be applied to any netfilter.
4232 @option{all}: the filter is attached both to the receive and the transmit
4233 queue of the netdev (default).
4235 @option{rx}: the filter is attached to the receive queue of the netdev,
4236 where it will receive packets sent to the netdev.
4238 @option{tx}: the filter is attached to the transmit queue of the netdev,
4239 where it will receive packets sent by the netdev.
4241 @item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid}[,queue=@var{all|rx|tx}]
4243 filter-mirror on netdev @var{netdevid},mirror net packet to chardev
4246 @item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},
4247 outdev=@var{chardevid}[,queue=@var{all|rx|tx}]
4249 filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev
4250 @
var{chardevid
},and redirect indev
's packet to filter.
4251 Create a filter-redirector we need to differ outdev id from indev id, id can not
4252 be the same. we can just use indev or outdev, but at least one of indev or outdev
4253 need to be specified.
4255 @item -object filter-rewriter,id=@var{id},netdev=@var{netdevid}[,queue=@var{all|rx|tx}]
4257 Filter-rewriter is a part of COLO project.It will rewrite tcp packet to
4258 secondary from primary to keep secondary tcp connection,and rewrite
4259 tcp packet to primary from secondary make tcp packet can be handled by
4264 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4265 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4266 -object filter-rewriter,id=rew0,netdev=hn0,queue=all
4268 @item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}]
4270 Dump the network traffic on netdev @var{dev} to the file specified by
4271 @var{filename}. At most @var{len} bytes (64k by default) per packet are stored.
4272 The file format is libpcap, so it can be analyzed with tools such as tcpdump
4275 @item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},
4276 outdev=@var{chardevid}
4278 Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with
4279 secondary packet. If the packets are same, we will output primary
4280 packet to outdev@var{chardevid}, else we will notify colo-frame
4281 do checkpoint and send primary packet to outdev@var{chardevid}.
4283 we must use it with the help of filter-mirror and filter-redirector.
4288 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown
4289 -device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66
4290 -chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait
4291 -chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait
4292 -chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait
4293 -chardev socket,id=compare0-0,host=3.3.3.3,port=9001
4294 -chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait
4295 -chardev socket,id=compare_out0,host=3.3.3.3,port=9005
4296 -object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0
4297 -object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out
4298 -object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0
4299 -object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0
4302 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown
4303 -device e1000,netdev=hn0,mac=52:a4:00:12:78:66
4304 -chardev socket,id=red0,host=3.3.3.3,port=9003
4305 -chardev socket,id=red1,host=3.3.3.3,port=9004
4306 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4307 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4311 If you want to know the detail of above command line, you can read
4312 the colo-compare git log.
4314 @item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}]
4316 Creates a cryptodev backend which executes crypto opreation from
4317 the QEMU cipher APIS. The @var{id} parameter is
4318 a unique ID that will be used to reference this cryptodev backend from
4319 the @option{virtio-crypto} device. The @var{queues} parameter is optional,
4320 which specify the queue number of cryptodev backend, the default of
4325 # qemu-system-x86_64 \
4327 -object cryptodev-backend-builtin,id=cryptodev0 \
4328 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4332 @item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4333 @item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4335 Defines a secret to store a password, encryption key, or some other sensitive
4336 data. The sensitive data can either be passed directly via the @var{data}
4337 parameter, or indirectly via the @var{file} parameter. Using the @var{data}
4338 parameter is insecure unless the sensitive data is encrypted.
4340 The sensitive data can be provided in raw format (the default), or base64.
4341 When encoded as JSON, the raw format only supports valid UTF-8 characters,
4342 so base64 is recommended for sending binary data. QEMU will convert from
4343 which ever format is provided to the format it needs internally. eg, an
4344 RBD password can be provided in raw format, even though it will be base64
4345 encoded when passed onto the RBD sever.
4347 For added protection, it is possible to encrypt the data associated with
4348 a secret using the AES-256-CBC cipher. Use of encryption is indicated
4349 by providing the @var{keyid} and @var{iv} parameters. The @var{keyid}
4350 parameter provides the ID of a previously defined secret that contains
4351 the AES-256 decryption key. This key should be 32-bytes long and be
4352 base64 encoded. The @var{iv} parameter provides the random initialization
4353 vector used for encryption of this particular secret and should be a
4354 base64 encrypted string of the 16-byte IV.
4356 The simplest (insecure) usage is to provide the secret inline
4360 # $QEMU -object secret,id=sec0,data=letmein,format=raw
4364 The simplest secure usage is to provide the secret via a file
4366 # echo -n "letmein" > mypasswd.txt
4367 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw
4369 For greater security, AES-256-CBC should be used. To illustrate usage,
4370 consider the openssl command line tool which can encrypt the data. Note
4371 that when encrypting, the plaintext must be padded to the cipher block
4372 size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm.
4374 First a master key needs to be created in base64 encoding:
4377 # openssl rand -base64 32 > key.b64
4378 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"')
4381 Each secret to be encrypted needs to have a random initialization vector
4382 generated. These do not need to be kept secret
4385 # openssl rand -base64 16 > iv.b64
4386 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"')
4389 The secret to be defined can now be encrypted, in this case we're
4390 telling openssl to base64 encode the result
, but it could be left
4391 as raw bytes
if desired
.
4394 # SECRET
=$
(echo
-n
"letmein" |
4395 openssl enc
-aes
-256-cbc
-a
-K $KEY
-iv $IV
)
4398 When launching QEMU
, create a master secret pointing to @code
{key
.b64
}
4399 and specify that to be used to decrypt the user password
. Pass the
4400 contents of @code
{iv
.b64
} to the second secret
4404 -object secret
,id
=secmaster0
,format
=base64
,file
=key
.b64 \
4405 -object secret
,id
=sec0
,keyid
=secmaster0
,format
=base64
,\
4406 data
=$SECRET
,iv
=$
(<iv
.b64
)
4414 HXCOMM This is the last statement
. Insert
new options before
this line
!