Merge remote-tracking branch 'remotes/kraxel/tags/pull-ui-20160324-1' into staging
[qemu.git] / qemu-options.hx
blobb98fa3e1f107482f85337ab01bf8d7891448b1fd
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
6 HXCOMM architectures.
7 HXCOMM HXCOMM can be used for comments, discarded from both texi and C
9 DEFHEADING(Standard options:)
10 STEXI
11 @table @option
12 ETEXI
14 DEF("help", 0, QEMU_OPTION_h,
15 "-h or -help display this help and exit\n", QEMU_ARCH_ALL)
16 STEXI
17 @item -h
18 @findex -h
19 Display help and exit
20 ETEXI
22 DEF("version", 0, QEMU_OPTION_version,
23 "-version display version information and exit\n", QEMU_ARCH_ALL)
24 STEXI
25 @item -version
26 @findex -version
27 Display version information and exit
28 ETEXI
30 DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
31 "-machine [type=]name[,prop[=value][,...]]\n"
32 " selects emulated machine ('-machine help' for list)\n"
33 " property accel=accel1[:accel2[:...]] selects accelerator\n"
34 " supported accelerators are kvm, xen, tcg (default: tcg)\n"
35 " kernel_irqchip=on|off controls accelerated irqchip support\n"
36 " kernel_irqchip=on|off|split controls accelerated irqchip support (default=off)\n"
37 " vmport=on|off|auto controls emulation of vmport (default: auto)\n"
38 " kvm_shadow_mem=size of KVM shadow MMU\n"
39 " dump-guest-core=on|off include guest memory in a core dump (default=on)\n"
40 " mem-merge=on|off controls memory merge support (default: on)\n"
41 " iommu=on|off controls emulated Intel IOMMU (VT-d) support (default=off)\n"
42 " igd-passthru=on|off controls IGD GFX passthrough support (default=off)\n"
43 " aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n"
44 " dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n"
45 " suppress-vmdesc=on|off disables self-describing migration (default=off)\n"
46 " nvdimm=on|off controls NVDIMM support (default=off)\n"
47 " enforce-config-section=on|off enforce configuration section migration (default=off)\n",
48 QEMU_ARCH_ALL)
49 STEXI
50 @item -machine [type=]@var{name}[,prop=@var{value}[,...]]
51 @findex -machine
52 Select the emulated machine by @var{name}. Use @code{-machine help} to list
53 available machines. Supported machine properties are:
54 @table @option
55 @item accel=@var{accels1}[:@var{accels2}[:...]]
56 This is used to enable an accelerator. Depending on the target architecture,
57 kvm, xen, or tcg can be available. By default, tcg is used. If there is more
58 than one accelerator specified, the next one is used if the previous one fails
59 to initialize.
60 @item kernel_irqchip=on|off
61 Controls in-kernel irqchip support for the chosen accelerator when available.
62 @item gfx_passthru=on|off
63 Enables IGD GFX passthrough support for the chosen machine when available.
64 @item vmport=on|off|auto
65 Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the
66 value based on accel. For accel=xen the default is off otherwise the default
67 is on.
68 @item kvm_shadow_mem=size
69 Defines the size of the KVM shadow MMU.
70 @item dump-guest-core=on|off
71 Include guest memory in a core dump. The default is on.
72 @item mem-merge=on|off
73 Enables or disables memory merge support. This feature, when supported by
74 the host, de-duplicates identical memory pages among VMs instances
75 (enabled by default).
76 @item iommu=on|off
77 Enables or disables emulated Intel IOMMU (VT-d) support. The default is off.
78 @item aes-key-wrap=on|off
79 Enables or disables AES key wrapping support on s390-ccw hosts. This feature
80 controls whether AES wrapping keys will be created to allow
81 execution of AES cryptographic functions. The default is on.
82 @item dea-key-wrap=on|off
83 Enables or disables DEA key wrapping support on s390-ccw hosts. This feature
84 controls whether DEA wrapping keys will be created to allow
85 execution of DEA cryptographic functions. The default is on.
86 @item nvdimm=on|off
87 Enables or disables NVDIMM support. The default is off.
88 @end table
89 ETEXI
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)
96 STEXI
97 @item -cpu @var{model}
98 @findex -cpu
99 Select CPU model (@code{-cpu help} for list and additional feature selection)
100 ETEXI
102 DEF("smp", HAS_ARG, QEMU_OPTION_smp,
103 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
104 " set the number of CPUs to 'n' [default=1]\n"
105 " maxcpus= maximum number of total cpus, including\n"
106 " offline CPUs for hotplug, etc\n"
107 " cores= number of CPU cores on one socket\n"
108 " threads= number of threads on one CPU core\n"
109 " sockets= number of discrete sockets in the system\n",
110 QEMU_ARCH_ALL)
111 STEXI
112 @item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
113 @findex -smp
114 Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
115 CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
116 to 4.
117 For the PC target, the number of @var{cores} per socket, the number
118 of @var{threads} per cores and the total number of @var{sockets} can be
119 specified. Missing values will be computed. If any on the three values is
120 given, the total number of CPUs @var{n} can be omitted. @var{maxcpus}
121 specifies the maximum number of hotpluggable CPUs.
122 ETEXI
124 DEF("numa", HAS_ARG, QEMU_OPTION_numa,
125 "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n"
126 "-numa node[,memdev=id][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL)
127 STEXI
128 @item -numa node[,mem=@var{size}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}]
129 @itemx -numa node[,memdev=@var{id}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}]
130 @findex -numa
131 Simulate a multi node NUMA system. If @samp{mem}, @samp{memdev}
132 and @samp{cpus} are omitted, resources are split equally. Also, note
133 that the -@option{numa} option doesn't allocate any of the specified
134 resources. That is, it just assigns existing resources to NUMA nodes. This
135 means that one still has to use the @option{-m}, @option{-smp} options
136 to allocate RAM and VCPUs respectively, and possibly @option{-object}
137 to specify the memory backend for the @samp{memdev} suboption.
139 @samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, if one
140 node uses @samp{memdev}, all of them have to use it.
141 ETEXI
143 DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
144 "-add-fd fd=fd,set=set[,opaque=opaque]\n"
145 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL)
146 STEXI
147 @item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}]
148 @findex -add-fd
150 Add a file descriptor to an fd set. Valid options are:
152 @table @option
153 @item fd=@var{fd}
154 This option defines the file descriptor of which a duplicate is added to fd set.
155 The file descriptor cannot be stdin, stdout, or stderr.
156 @item set=@var{set}
157 This option defines the ID of the fd set to add the file descriptor to.
158 @item opaque=@var{opaque}
159 This option defines a free-form string that can be used to describe @var{fd}.
160 @end table
162 You can open an image using pre-opened file descriptors from an fd set:
163 @example
164 qemu-system-i386
165 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
166 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
167 -drive file=/dev/fdset/2,index=0,media=disk
168 @end example
169 ETEXI
171 DEF("set", HAS_ARG, QEMU_OPTION_set,
172 "-set group.id.arg=value\n"
173 " set <arg> parameter for item <id> of type <group>\n"
174 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL)
175 STEXI
176 @item -set @var{group}.@var{id}.@var{arg}=@var{value}
177 @findex -set
178 Set parameter @var{arg} for item @var{id} of type @var{group}\n"
179 ETEXI
181 DEF("global", HAS_ARG, QEMU_OPTION_global,
182 "-global driver.property=value\n"
183 "-global driver=driver,property=property,value=value\n"
184 " set a global default for a driver property\n",
185 QEMU_ARCH_ALL)
186 STEXI
187 @item -global @var{driver}.@var{prop}=@var{value}
188 @itemx -global driver=@var{driver},property=@var{property},value=@var{value}
189 @findex -global
190 Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.:
192 @example
193 qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk
194 @end example
196 In particular, you can use this to set driver properties for devices which are
197 created automatically by the machine model. To create a device which is not
198 created automatically and set properties on it, use -@option{device}.
200 -global @var{driver}.@var{prop}=@var{value} is shorthand for -global
201 driver=@var{driver},property=@var{prop},value=@var{value}. The
202 longhand syntax works even when @var{driver} contains a dot.
203 ETEXI
205 DEF("boot", HAS_ARG, QEMU_OPTION_boot,
206 "-boot [order=drives][,once=drives][,menu=on|off]\n"
207 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
208 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
209 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n"
210 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n"
211 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n",
212 QEMU_ARCH_ALL)
213 STEXI
214 @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]
215 @findex -boot
216 Specify boot order @var{drives} as a string of drive letters. Valid
217 drive letters depend on the target architecture. The x86 PC uses: a, b
218 (floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
219 from network adapter 1-4), hard disk boot is the default. To apply a
220 particular boot order only on the first startup, specify it via
221 @option{once}.
223 Interactive boot menus/prompts can be enabled via @option{menu=on} as far
224 as firmware/BIOS supports them. The default is non-interactive boot.
226 A splash picture could be passed to bios, enabling user to show it as logo,
227 when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
228 supports them. Currently Seabios for X86 system support it.
229 limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
230 format(true color). The resolution should be supported by the SVGA mode, so
231 the recommended is 320x240, 640x480, 800x640.
233 A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms
234 when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not
235 reboot, qemu passes '-1' to bios by default. Currently Seabios for X86
236 system support it.
238 Do strict boot via @option{strict=on} as far as firmware/BIOS
239 supports it. This only effects when boot priority is changed by
240 bootindex options. The default is non-strict boot.
242 @example
243 # try to boot from network first, then from hard disk
244 qemu-system-i386 -boot order=nc
245 # boot from CD-ROM first, switch back to default order after reboot
246 qemu-system-i386 -boot once=d
247 # boot with a splash picture for 5 seconds.
248 qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
249 @end example
251 Note: The legacy format '-boot @var{drives}' is still supported but its
252 use is discouraged as it may be removed from future versions.
253 ETEXI
255 DEF("m", HAS_ARG, QEMU_OPTION_m,
256 "-m[emory] [size=]megs[,slots=n,maxmem=size]\n"
257 " configure guest RAM\n"
258 " size: initial amount of guest memory\n"
259 " slots: number of hotplug slots (default: none)\n"
260 " maxmem: maximum amount of guest memory (default: none)\n"
261 "NOTE: Some architectures might enforce a specific granularity\n",
262 QEMU_ARCH_ALL)
263 STEXI
264 @item -m [size=]@var{megs}[,slots=n,maxmem=size]
265 @findex -m
266 Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB.
267 Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in
268 megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem}
269 could be used to set amount of hotpluggable memory slots and maximum amount of
270 memory. Note that @var{maxmem} must be aligned to the page size.
272 For example, the following command-line sets the guest startup RAM size to
273 1GB, creates 3 slots to hotplug additional memory and sets the maximum
274 memory the guest can reach to 4GB:
276 @example
277 qemu-system-x86_64 -m 1G,slots=3,maxmem=4G
278 @end example
280 If @var{slots} and @var{maxmem} are not specified, memory hotplug won't
281 be enabled and the guest startup RAM will never increase.
282 ETEXI
284 DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
285 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
286 STEXI
287 @item -mem-path @var{path}
288 @findex -mem-path
289 Allocate guest RAM from a temporarily created file in @var{path}.
290 ETEXI
292 DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
293 "-mem-prealloc preallocate guest memory (use with -mem-path)\n",
294 QEMU_ARCH_ALL)
295 STEXI
296 @item -mem-prealloc
297 @findex -mem-prealloc
298 Preallocate memory when using -mem-path.
299 ETEXI
301 DEF("k", HAS_ARG, QEMU_OPTION_k,
302 "-k language use keyboard layout (for example 'fr' for French)\n",
303 QEMU_ARCH_ALL)
304 STEXI
305 @item -k @var{language}
306 @findex -k
307 Use keyboard layout @var{language} (for example @code{fr} for
308 French). This option is only needed where it is not easy to get raw PC
309 keycodes (e.g. on Macs, with some X11 servers or with a VNC
310 display). You don't normally need to use it on PC/Linux or PC/Windows
311 hosts.
313 The available layouts are:
314 @example
315 ar de-ch es fo fr-ca hu ja mk no pt-br sv
316 da en-gb et fr fr-ch is lt nl pl ru th
317 de en-us fi fr-be hr it lv nl-be pt sl tr
318 @end example
320 The default is @code{en-us}.
321 ETEXI
324 DEF("audio-help", 0, QEMU_OPTION_audio_help,
325 "-audio-help print list of audio drivers and their options\n",
326 QEMU_ARCH_ALL)
327 STEXI
328 @item -audio-help
329 @findex -audio-help
330 Will show the audio subsystem help: list of drivers, tunable
331 parameters.
332 ETEXI
334 DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
335 "-soundhw c1,... enable audio support\n"
336 " and only specified sound cards (comma separated list)\n"
337 " use '-soundhw help' to get the list of supported cards\n"
338 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL)
339 STEXI
340 @item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
341 @findex -soundhw
342 Enable audio and selected sound hardware. Use 'help' to print all
343 available sound hardware.
345 @example
346 qemu-system-i386 -soundhw sb16,adlib disk.img
347 qemu-system-i386 -soundhw es1370 disk.img
348 qemu-system-i386 -soundhw ac97 disk.img
349 qemu-system-i386 -soundhw hda disk.img
350 qemu-system-i386 -soundhw all disk.img
351 qemu-system-i386 -soundhw help
352 @end example
354 Note that Linux's i810_audio OSS kernel (for AC97) module might
355 require manually specifying clocking.
357 @example
358 modprobe i810_audio clocking=48000
359 @end example
360 ETEXI
362 DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
363 "-balloon none disable balloon device\n"
364 "-balloon virtio[,addr=str]\n"
365 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL)
366 STEXI
367 @item -balloon none
368 @findex -balloon
369 Disable balloon device.
370 @item -balloon virtio[,addr=@var{addr}]
371 Enable virtio balloon device (default), optionally with PCI address
372 @var{addr}.
373 ETEXI
375 DEF("device", HAS_ARG, QEMU_OPTION_device,
376 "-device driver[,prop[=value][,...]]\n"
377 " add device (based on driver)\n"
378 " prop=value,... sets driver properties\n"
379 " use '-device help' to print all possible drivers\n"
380 " use '-device driver,help' to print all possible properties\n",
381 QEMU_ARCH_ALL)
382 STEXI
383 @item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
384 @findex -device
385 Add device @var{driver}. @var{prop}=@var{value} sets driver
386 properties. Valid properties depend on the driver. To get help on
387 possible drivers and properties, use @code{-device help} and
388 @code{-device @var{driver},help}.
390 Some drivers are:
391 @item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}]
393 Add an IPMI BMC. This is a simulation of a hardware management
394 interface processor that normally sits on a system. It provides
395 a watchdog and the ability to reset and power control the system.
396 You need to connect this to an IPMI interface to make it useful
398 The IPMI slave address to use for the BMC. The default is 0x20.
399 This address is the BMC's address on the I2C network of management
400 controllers. If you don't know what this means, it is safe to ignore
403 @item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}]
405 Add a connection to an external IPMI BMC simulator. Instead of
406 locally emulating the BMC like the above item, instead connect
407 to an external entity that provides the IPMI services.
409 A connection is made to an external BMC simulator. If you do this, it
410 is strongly recommended that you use the "reconnect=" chardev option
411 to reconnect to the simulator if the connection is lost. Note that if
412 this is not used carefully, it can be a security issue, as the
413 interface has the ability to send resets, NMIs, and power off the VM.
414 It's best if QEMU makes a connection to an external simulator running
415 on a secure port on localhost, so neither the simulator nor QEMU is
416 exposed to any outside network.
418 See the "lanserv/README.vm" file in the OpenIPMI library for more
419 details on the external interface.
421 @item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
423 Add a KCS IPMI interafce on the ISA bus. This also adds a
424 corresponding ACPI and SMBIOS entries, if appropriate.
426 @table @option
427 @item bmc=@var{id}
428 The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
429 @item ioport=@var{val}
430 Define the I/O address of the interface. The default is 0xca0 for KCS.
431 @item irq=@var{val}
432 Define the interrupt to use. The default is 5. To disable interrupts,
433 set this to 0.
434 @end table
436 @item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
438 Like the KCS interface, but defines a BT interface. The default port is
439 0xe4 and the default interrupt is 5.
441 ETEXI
443 DEF("name", HAS_ARG, QEMU_OPTION_name,
444 "-name string1[,process=string2][,debug-threads=on|off]\n"
445 " set the name of the guest\n"
446 " string1 sets the window title and string2 the process name (on Linux)\n"
447 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n"
448 " NOTE: The thread names are for debugging and not a stable API.\n",
449 QEMU_ARCH_ALL)
450 STEXI
451 @item -name @var{name}
452 @findex -name
453 Sets the @var{name} of the guest.
454 This name will be displayed in the SDL window caption.
455 The @var{name} will also be used for the VNC server.
456 Also optionally set the top visible process name in Linux.
457 Naming of individual threads can also be enabled on Linux to aid debugging.
458 ETEXI
460 DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
461 "-uuid %08x-%04x-%04x-%04x-%012x\n"
462 " specify machine UUID\n", QEMU_ARCH_ALL)
463 STEXI
464 @item -uuid @var{uuid}
465 @findex -uuid
466 Set system UUID.
467 ETEXI
469 STEXI
470 @end table
471 ETEXI
472 DEFHEADING()
474 DEFHEADING(Block device options:)
475 STEXI
476 @table @option
477 ETEXI
479 DEF("fda", HAS_ARG, QEMU_OPTION_fda,
480 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
481 DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
482 STEXI
483 @item -fda @var{file}
484 @itemx -fdb @var{file}
485 @findex -fda
486 @findex -fdb
487 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}).
488 ETEXI
490 DEF("hda", HAS_ARG, QEMU_OPTION_hda,
491 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
492 DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
493 DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
494 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
495 DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
496 STEXI
497 @item -hda @var{file}
498 @itemx -hdb @var{file}
499 @itemx -hdc @var{file}
500 @itemx -hdd @var{file}
501 @findex -hda
502 @findex -hdb
503 @findex -hdc
504 @findex -hdd
505 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
506 ETEXI
508 DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
509 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
510 QEMU_ARCH_ALL)
511 STEXI
512 @item -cdrom @var{file}
513 @findex -cdrom
514 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
515 @option{-cdrom} at the same time). You can use the host CD-ROM by
516 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
517 ETEXI
519 DEF("drive", HAS_ARG, QEMU_OPTION_drive,
520 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
521 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
522 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
523 " [,serial=s][,addr=A][,rerror=ignore|stop|report]\n"
524 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n"
525 " [,readonly=on|off][,copy-on-read=on|off]\n"
526 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n"
527 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n"
528 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n"
529 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n"
530 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n"
531 " [[,iops_size=is]]\n"
532 " [[,group=g]]\n"
533 " use 'file' as a drive image\n", QEMU_ARCH_ALL)
534 STEXI
535 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
536 @findex -drive
538 Define a new drive. Valid options are:
540 @table @option
541 @item file=@var{file}
542 This option defines which disk image (@pxref{disk_images}) to use with
543 this drive. If the filename contains comma, you must double it
544 (for instance, "file=my,,file" to use file "my,file").
546 Special files such as iSCSI devices can be specified using protocol
547 specific URLs. See the section for "Device URL Syntax" for more information.
548 @item if=@var{interface}
549 This option defines on which type on interface the drive is connected.
550 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio.
551 @item bus=@var{bus},unit=@var{unit}
552 These options define where is connected the drive by defining the bus number and
553 the unit id.
554 @item index=@var{index}
555 This option defines where is connected the drive by using an index in the list
556 of available connectors of a given interface type.
557 @item media=@var{media}
558 This option defines the type of the media: disk or cdrom.
559 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
560 These options have the same definition as they have in @option{-hdachs}.
561 @item snapshot=@var{snapshot}
562 @var{snapshot} is "on" or "off" and controls snapshot mode for the given drive
563 (see @option{-snapshot}).
564 @item cache=@var{cache}
565 @var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data.
566 @item aio=@var{aio}
567 @var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
568 @item discard=@var{discard}
569 @var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls whether @dfn{discard} (also known as @dfn{trim} or @dfn{unmap}) requests are ignored or passed to the filesystem. Some machine types may not support discard requests.
570 @item format=@var{format}
571 Specify which disk @var{format} will be used rather than detecting
572 the format. Can be used to specifiy format=raw to avoid interpreting
573 an untrusted format header.
574 @item serial=@var{serial}
575 This option specifies the serial number to assign to the device.
576 @item addr=@var{addr}
577 Specify the controller's PCI address (if=virtio only).
578 @item werror=@var{action},rerror=@var{action}
579 Specify which @var{action} to take on write and read errors. Valid actions are:
580 "ignore" (ignore the error and try to continue), "stop" (pause QEMU),
581 "report" (report the error to the guest), "enospc" (pause QEMU only if the
582 host disk is full; report the error to the guest otherwise).
583 The default setting is @option{werror=enospc} and @option{rerror=report}.
584 @item readonly
585 Open drive @option{file} as read-only. Guest write attempts will fail.
586 @item copy-on-read=@var{copy-on-read}
587 @var{copy-on-read} is "on" or "off" and enables whether to copy read backing
588 file sectors into the image file.
589 @item detect-zeroes=@var{detect-zeroes}
590 @var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic
591 conversion of plain zero writes by the OS to driver specific optimized
592 zero write commands. You may even choose "unmap" if @var{discard} is set
593 to "unmap" to allow a zero write to be converted to an UNMAP operation.
594 @end table
596 By default, the @option{cache=writeback} mode is used. It will report data
597 writes as completed as soon as the data is present in the host page cache.
598 This is safe as long as your guest OS makes sure to correctly flush disk caches
599 where needed. If your guest OS does not handle volatile disk write caches
600 correctly and your host crashes or loses power, then the guest may experience
601 data corruption.
603 For such guests, you should consider using @option{cache=writethrough}. This
604 means that the host page cache will be used to read and write data, but write
605 notification will be sent to the guest only after QEMU has made sure to flush
606 each write to the disk. Be aware that this has a major impact on performance.
608 The host page cache can be avoided entirely with @option{cache=none}. This will
609 attempt to do disk IO directly to the guest's memory. QEMU may still perform
610 an internal copy of the data. Note that this is considered a writeback mode and
611 the guest OS must handle the disk write cache correctly in order to avoid data
612 corruption on host crashes.
614 The host page cache can be avoided while only sending write notifications to
615 the guest when the data has been flushed to the disk using
616 @option{cache=directsync}.
618 In case you don't care about data integrity over host failures, use
619 @option{cache=unsafe}. This option tells QEMU that it never needs to write any
620 data to the disk but can instead keep things in cache. If anything goes wrong,
621 like your host losing power, the disk storage getting disconnected accidentally,
622 etc. your image will most probably be rendered unusable. When using
623 the @option{-snapshot} option, unsafe caching is always used.
625 Copy-on-read avoids accessing the same backing file sectors repeatedly and is
626 useful when the backing file is over a slow network. By default copy-on-read
627 is off.
629 Instead of @option{-cdrom} you can use:
630 @example
631 qemu-system-i386 -drive file=file,index=2,media=cdrom
632 @end example
634 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
635 use:
636 @example
637 qemu-system-i386 -drive file=file,index=0,media=disk
638 qemu-system-i386 -drive file=file,index=1,media=disk
639 qemu-system-i386 -drive file=file,index=2,media=disk
640 qemu-system-i386 -drive file=file,index=3,media=disk
641 @end example
643 You can open an image using pre-opened file descriptors from an fd set:
644 @example
645 qemu-system-i386
646 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
647 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
648 -drive file=/dev/fdset/2,index=0,media=disk
649 @end example
651 You can connect a CDROM to the slave of ide0:
652 @example
653 qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
654 @end example
656 If you don't specify the "file=" argument, you define an empty drive:
657 @example
658 qemu-system-i386 -drive if=ide,index=1,media=cdrom
659 @end example
661 You can connect a SCSI disk with unit ID 6 on the bus #0:
662 @example
663 qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6
664 @end example
666 Instead of @option{-fda}, @option{-fdb}, you can use:
667 @example
668 qemu-system-i386 -drive file=file,index=0,if=floppy
669 qemu-system-i386 -drive file=file,index=1,if=floppy
670 @end example
672 By default, @var{interface} is "ide" and @var{index} is automatically
673 incremented:
674 @example
675 qemu-system-i386 -drive file=a -drive file=b"
676 @end example
677 is interpreted like:
678 @example
679 qemu-system-i386 -hda a -hdb b
680 @end example
681 ETEXI
683 DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
684 "-mtdblock file use 'file' as on-board Flash memory image\n",
685 QEMU_ARCH_ALL)
686 STEXI
687 @item -mtdblock @var{file}
688 @findex -mtdblock
689 Use @var{file} as on-board Flash memory image.
690 ETEXI
692 DEF("sd", HAS_ARG, QEMU_OPTION_sd,
693 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL)
694 STEXI
695 @item -sd @var{file}
696 @findex -sd
697 Use @var{file} as SecureDigital card image.
698 ETEXI
700 DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
701 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL)
702 STEXI
703 @item -pflash @var{file}
704 @findex -pflash
705 Use @var{file} as a parallel flash image.
706 ETEXI
708 DEF("snapshot", 0, QEMU_OPTION_snapshot,
709 "-snapshot write to temporary files instead of disk image files\n",
710 QEMU_ARCH_ALL)
711 STEXI
712 @item -snapshot
713 @findex -snapshot
714 Write to temporary files instead of disk image files. In this case,
715 the raw disk image you use is not written back. You can however force
716 the write back by pressing @key{C-a s} (@pxref{disk_images}).
717 ETEXI
719 DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
720 "-hdachs c,h,s[,t]\n" \
721 " force hard disk 0 physical geometry and the optional BIOS\n" \
722 " translation (t=none or lba) (usually QEMU can guess them)\n",
723 QEMU_ARCH_ALL)
724 STEXI
725 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
726 @findex -hdachs
727 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
728 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
729 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
730 all those parameters. This option is useful for old MS-DOS disk
731 images.
732 ETEXI
734 DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
735 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
736 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
737 QEMU_ARCH_ALL)
739 STEXI
741 @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}]
742 @findex -fsdev
743 Define a new file system device. Valid options are:
744 @table @option
745 @item @var{fsdriver}
746 This option specifies the fs driver backend to use.
747 Currently "local", "handle" and "proxy" file system drivers are supported.
748 @item id=@var{id}
749 Specifies identifier for this device
750 @item path=@var{path}
751 Specifies the export path for the file system device. Files under
752 this path will be available to the 9p client on the guest.
753 @item security_model=@var{security_model}
754 Specifies the security model to be used for this export path.
755 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
756 In "passthrough" security model, files are stored using the same
757 credentials as they are created on the guest. This requires QEMU
758 to run as root. In "mapped-xattr" security model, some of the file
759 attributes like uid, gid, mode bits and link target are stored as
760 file attributes. For "mapped-file" these attributes are stored in the
761 hidden .virtfs_metadata directory. Directories exported by this security model cannot
762 interact with other unix tools. "none" security model is same as
763 passthrough except the sever won't report failures if it fails to
764 set file attributes like ownership. Security model is mandatory
765 only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
766 security model as a parameter.
767 @item writeout=@var{writeout}
768 This is an optional argument. The only supported value is "immediate".
769 This means that host page cache will be used to read and write data but
770 write notification will be sent to the guest only when the data has been
771 reported as written by the storage subsystem.
772 @item readonly
773 Enables exporting 9p share as a readonly mount for guests. By default
774 read-write access is given.
775 @item socket=@var{socket}
776 Enables proxy filesystem driver to use passed socket file for communicating
777 with virtfs-proxy-helper
778 @item sock_fd=@var{sock_fd}
779 Enables proxy filesystem driver to use passed socket descriptor for
780 communicating with virtfs-proxy-helper. Usually a helper like libvirt
781 will create socketpair and pass one of the fds as sock_fd
782 @end table
784 -fsdev option is used along with -device driver "virtio-9p-pci".
785 @item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
786 Options for virtio-9p-pci driver are:
787 @table @option
788 @item fsdev=@var{id}
789 Specifies the id value specified along with -fsdev option
790 @item mount_tag=@var{mount_tag}
791 Specifies the tag name to be used by the guest to mount this export point
792 @end table
794 ETEXI
796 DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
797 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
798 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
799 QEMU_ARCH_ALL)
801 STEXI
803 @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}]
804 @findex -virtfs
806 The general form of a Virtual File system pass-through options are:
807 @table @option
808 @item @var{fsdriver}
809 This option specifies the fs driver backend to use.
810 Currently "local", "handle" and "proxy" file system drivers are supported.
811 @item id=@var{id}
812 Specifies identifier for this device
813 @item path=@var{path}
814 Specifies the export path for the file system device. Files under
815 this path will be available to the 9p client on the guest.
816 @item security_model=@var{security_model}
817 Specifies the security model to be used for this export path.
818 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
819 In "passthrough" security model, files are stored using the same
820 credentials as they are created on the guest. This requires QEMU
821 to run as root. In "mapped-xattr" security model, some of the file
822 attributes like uid, gid, mode bits and link target are stored as
823 file attributes. For "mapped-file" these attributes are stored in the
824 hidden .virtfs_metadata directory. Directories exported by this security model cannot
825 interact with other unix tools. "none" security model is same as
826 passthrough except the sever won't report failures if it fails to
827 set file attributes like ownership. Security model is mandatory only
828 for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
829 model as a parameter.
830 @item writeout=@var{writeout}
831 This is an optional argument. The only supported value is "immediate".
832 This means that host page cache will be used to read and write data but
833 write notification will be sent to the guest only when the data has been
834 reported as written by the storage subsystem.
835 @item readonly
836 Enables exporting 9p share as a readonly mount for guests. By default
837 read-write access is given.
838 @item socket=@var{socket}
839 Enables proxy filesystem driver to use passed socket file for
840 communicating with virtfs-proxy-helper. Usually a helper like libvirt
841 will create socketpair and pass one of the fds as sock_fd
842 @item sock_fd
843 Enables proxy filesystem driver to use passed 'sock_fd' as the socket
844 descriptor for interfacing with virtfs-proxy-helper
845 @end table
846 ETEXI
848 DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
849 "-virtfs_synth Create synthetic file system image\n",
850 QEMU_ARCH_ALL)
851 STEXI
852 @item -virtfs_synth
853 @findex -virtfs_synth
854 Create synthetic file system image
855 ETEXI
857 STEXI
858 @end table
859 ETEXI
860 DEFHEADING()
862 DEFHEADING(USB options:)
863 STEXI
864 @table @option
865 ETEXI
867 DEF("usb", 0, QEMU_OPTION_usb,
868 "-usb enable the USB driver (will be the default soon)\n",
869 QEMU_ARCH_ALL)
870 STEXI
871 @item -usb
872 @findex -usb
873 Enable the USB driver (will be the default soon)
874 ETEXI
876 DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
877 "-usbdevice name add the host or guest USB device 'name'\n",
878 QEMU_ARCH_ALL)
879 STEXI
881 @item -usbdevice @var{devname}
882 @findex -usbdevice
883 Add the USB device @var{devname}. @xref{usb_devices}.
885 @table @option
887 @item mouse
888 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
890 @item tablet
891 Pointer device that uses absolute coordinates (like a touchscreen). This
892 means QEMU is able to report the mouse position without having to grab the
893 mouse. Also overrides the PS/2 mouse emulation when activated.
895 @item disk:[format=@var{format}]:@var{file}
896 Mass storage device based on file. The optional @var{format} argument
897 will be used rather than detecting the format. Can be used to specifiy
898 @code{format=raw} to avoid interpreting an untrusted format header.
900 @item host:@var{bus}.@var{addr}
901 Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
903 @item host:@var{vendor_id}:@var{product_id}
904 Pass through the host device identified by @var{vendor_id}:@var{product_id}
905 (Linux only).
907 @item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
908 Serial converter to host character device @var{dev}, see @code{-serial} for the
909 available devices.
911 @item braille
912 Braille device. This will use BrlAPI to display the braille output on a real
913 or fake device.
915 @item net:@var{options}
916 Network adapter that supports CDC ethernet and RNDIS protocols.
918 @end table
919 ETEXI
921 STEXI
922 @end table
923 ETEXI
924 DEFHEADING()
926 DEFHEADING(Display options:)
927 STEXI
928 @table @option
929 ETEXI
931 DEF("display", HAS_ARG, QEMU_OPTION_display,
932 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
933 " [,window_close=on|off]|curses|none|\n"
934 " gtk[,grab_on_hover=on|off]|\n"
935 " vnc=<display>[,<optargs>]\n"
936 " select display type\n", QEMU_ARCH_ALL)
937 STEXI
938 @item -display @var{type}
939 @findex -display
940 Select type of display to use. This option is a replacement for the
941 old style -sdl/-curses/... options. Valid values for @var{type} are
942 @table @option
943 @item sdl
944 Display video output via SDL (usually in a separate graphics
945 window; see the SDL documentation for other possibilities).
946 @item curses
947 Display video output via curses. For graphics device models which
948 support a text mode, QEMU can display this output using a
949 curses/ncurses interface. Nothing is displayed when the graphics
950 device is in graphical mode or if the graphics device does not support
951 a text mode. Generally only the VGA device models support text mode.
952 @item none
953 Do not display video output. The guest will still see an emulated
954 graphics card, but its output will not be displayed to the QEMU
955 user. This option differs from the -nographic option in that it
956 only affects what is done with video output; -nographic also changes
957 the destination of the serial and parallel port data.
958 @item gtk
959 Display video output in a GTK window. This interface provides drop-down
960 menus and other UI elements to configure and control the VM during
961 runtime.
962 @item vnc
963 Start a VNC server on display <arg>
964 @end table
965 ETEXI
967 DEF("nographic", 0, QEMU_OPTION_nographic,
968 "-nographic disable graphical output and redirect serial I/Os to console\n",
969 QEMU_ARCH_ALL)
970 STEXI
971 @item -nographic
972 @findex -nographic
973 Normally, QEMU uses SDL to display the VGA output. With this option,
974 you can totally disable graphical output so that QEMU is a simple
975 command line application. The emulated serial port is redirected on
976 the console and muxed with the monitor (unless redirected elsewhere
977 explicitly). Therefore, you can still use QEMU to debug a Linux kernel
978 with a serial console. Use @key{C-a h} for help on switching between
979 the console and monitor.
980 ETEXI
982 DEF("curses", 0, QEMU_OPTION_curses,
983 "-curses use a curses/ncurses interface instead of SDL\n",
984 QEMU_ARCH_ALL)
985 STEXI
986 @item -curses
987 @findex -curses
988 Normally, QEMU uses SDL to display the VGA output. With this option,
989 QEMU can display the VGA output when in text mode using a
990 curses/ncurses interface. Nothing is displayed in graphical mode.
991 ETEXI
993 DEF("no-frame", 0, QEMU_OPTION_no_frame,
994 "-no-frame open SDL window without a frame and window decorations\n",
995 QEMU_ARCH_ALL)
996 STEXI
997 @item -no-frame
998 @findex -no-frame
999 Do not use decorations for SDL windows and start them using the whole
1000 available screen space. This makes the using QEMU in a dedicated desktop
1001 workspace more convenient.
1002 ETEXI
1004 DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
1005 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
1006 QEMU_ARCH_ALL)
1007 STEXI
1008 @item -alt-grab
1009 @findex -alt-grab
1010 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
1011 affects the special keys (for fullscreen, monitor-mode switching, etc).
1012 ETEXI
1014 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
1015 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
1016 QEMU_ARCH_ALL)
1017 STEXI
1018 @item -ctrl-grab
1019 @findex -ctrl-grab
1020 Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
1021 affects the special keys (for fullscreen, monitor-mode switching, etc).
1022 ETEXI
1024 DEF("no-quit", 0, QEMU_OPTION_no_quit,
1025 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL)
1026 STEXI
1027 @item -no-quit
1028 @findex -no-quit
1029 Disable SDL window close capability.
1030 ETEXI
1032 DEF("sdl", 0, QEMU_OPTION_sdl,
1033 "-sdl enable SDL\n", QEMU_ARCH_ALL)
1034 STEXI
1035 @item -sdl
1036 @findex -sdl
1037 Enable SDL.
1038 ETEXI
1040 DEF("spice", HAS_ARG, QEMU_OPTION_spice,
1041 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
1042 " [,x509-key-file=<file>][,x509-key-password=<file>]\n"
1043 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
1044 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n"
1045 " [,tls-ciphers=<list>]\n"
1046 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
1047 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
1048 " [,sasl][,password=<secret>][,disable-ticketing]\n"
1049 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
1050 " [,jpeg-wan-compression=[auto|never|always]]\n"
1051 " [,zlib-glz-wan-compression=[auto|never|always]]\n"
1052 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
1053 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
1054 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
1055 " [,gl=[on|off]]\n"
1056 " enable spice\n"
1057 " at least one of {port, tls-port} is mandatory\n",
1058 QEMU_ARCH_ALL)
1059 STEXI
1060 @item -spice @var{option}[,@var{option}[,...]]
1061 @findex -spice
1062 Enable the spice remote desktop protocol. Valid options are
1064 @table @option
1066 @item port=<nr>
1067 Set the TCP port spice is listening on for plaintext channels.
1069 @item addr=<addr>
1070 Set the IP address spice is listening on. Default is any address.
1072 @item ipv4
1073 @itemx ipv6
1074 @itemx unix
1075 Force using the specified IP version.
1077 @item password=<secret>
1078 Set the password you need to authenticate.
1080 @item sasl
1081 Require that the client use SASL to authenticate with the spice.
1082 The exact choice of authentication method used is controlled from the
1083 system / user's SASL configuration file for the 'qemu' service. This
1084 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1085 unprivileged user, an environment variable SASL_CONF_PATH can be used
1086 to make it search alternate locations for the service config.
1087 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1088 it is recommended that SASL always be combined with the 'tls' and
1089 'x509' settings to enable use of SSL and server certificates. This
1090 ensures a data encryption preventing compromise of authentication
1091 credentials.
1093 @item disable-ticketing
1094 Allow client connects without authentication.
1096 @item disable-copy-paste
1097 Disable copy paste between the client and the guest.
1099 @item disable-agent-file-xfer
1100 Disable spice-vdagent based file-xfer between the client and the guest.
1102 @item tls-port=<nr>
1103 Set the TCP port spice is listening on for encrypted channels.
1105 @item x509-dir=<dir>
1106 Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1108 @item x509-key-file=<file>
1109 @itemx x509-key-password=<file>
1110 @itemx x509-cert-file=<file>
1111 @itemx x509-cacert-file=<file>
1112 @itemx x509-dh-key-file=<file>
1113 The x509 file names can also be configured individually.
1115 @item tls-ciphers=<list>
1116 Specify which ciphers to use.
1118 @item tls-channel=[main|display|cursor|inputs|record|playback]
1119 @itemx plaintext-channel=[main|display|cursor|inputs|record|playback]
1120 Force specific channel to be used with or without TLS encryption. The
1121 options can be specified multiple times to configure multiple
1122 channels. The special name "default" can be used to set the default
1123 mode. For channels which are not explicitly forced into one mode the
1124 spice client is allowed to pick tls/plaintext as he pleases.
1126 @item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1127 Configure image compression (lossless).
1128 Default is auto_glz.
1130 @item jpeg-wan-compression=[auto|never|always]
1131 @itemx zlib-glz-wan-compression=[auto|never|always]
1132 Configure wan image compression (lossy for slow links).
1133 Default is auto.
1135 @item streaming-video=[off|all|filter]
1136 Configure video stream detection. Default is filter.
1138 @item agent-mouse=[on|off]
1139 Enable/disable passing mouse events via vdagent. Default is on.
1141 @item playback-compression=[on|off]
1142 Enable/disable audio stream compression (using celt 0.5.1). Default is on.
1144 @item seamless-migration=[on|off]
1145 Enable/disable spice seamless migration. Default is off.
1147 @item gl=[on|off]
1148 Enable/disable OpenGL context. Default is off.
1150 @end table
1151 ETEXI
1153 DEF("portrait", 0, QEMU_OPTION_portrait,
1154 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
1155 QEMU_ARCH_ALL)
1156 STEXI
1157 @item -portrait
1158 @findex -portrait
1159 Rotate graphical output 90 deg left (only PXA LCD).
1160 ETEXI
1162 DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1163 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
1164 QEMU_ARCH_ALL)
1165 STEXI
1166 @item -rotate @var{deg}
1167 @findex -rotate
1168 Rotate graphical output some deg left (only PXA LCD).
1169 ETEXI
1171 DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1172 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n"
1173 " select video card type\n", QEMU_ARCH_ALL)
1174 STEXI
1175 @item -vga @var{type}
1176 @findex -vga
1177 Select type of VGA card to emulate. Valid values for @var{type} are
1178 @table @option
1179 @item cirrus
1180 Cirrus Logic GD5446 Video card. All Windows versions starting from
1181 Windows 95 should recognize and use this graphic card. For optimal
1182 performances, use 16 bit color depth in the guest and the host OS.
1183 (This one is the default)
1184 @item std
1185 Standard VGA card with Bochs VBE extensions. If your guest OS
1186 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1187 to use high resolution modes (>= 1280x1024x16) then you should use
1188 this option.
1189 @item vmware
1190 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1191 recent XFree86/XOrg server or Windows guest with a driver for this
1192 card.
1193 @item qxl
1194 QXL paravirtual graphic card. It is VGA compatible (including VESA
1195 2.0 VBE support). Works best with qxl guest drivers installed though.
1196 Recommended choice when using the spice protocol.
1197 @item tcx
1198 (sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1199 sun4m machines and offers both 8-bit and 24-bit colour depths at a
1200 fixed resolution of 1024x768.
1201 @item cg3
1202 (sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1203 for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1204 resolutions aimed at people wishing to run older Solaris versions.
1205 @item virtio
1206 Virtio VGA card.
1207 @item none
1208 Disable VGA card.
1209 @end table
1210 ETEXI
1212 DEF("full-screen", 0, QEMU_OPTION_full_screen,
1213 "-full-screen start in full screen\n", QEMU_ARCH_ALL)
1214 STEXI
1215 @item -full-screen
1216 @findex -full-screen
1217 Start in full screen.
1218 ETEXI
1220 DEF("g", 1, QEMU_OPTION_g ,
1221 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
1222 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1223 STEXI
1224 @item -g @var{width}x@var{height}[x@var{depth}]
1225 @findex -g
1226 Set the initial graphical resolution and depth (PPC, SPARC only).
1227 ETEXI
1229 DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1230 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL)
1231 STEXI
1232 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1233 @findex -vnc
1234 Normally, QEMU uses SDL to display the VGA output. With this option,
1235 you can have QEMU listen on VNC display @var{display} and redirect the VGA
1236 display over the VNC session. It is very useful to enable the usb
1237 tablet device when using this option (option @option{-usbdevice
1238 tablet}). When using the VNC display, you must use the @option{-k}
1239 parameter to set the keyboard layout if you are not using en-us. Valid
1240 syntax for the @var{display} is
1242 @table @option
1244 @item @var{host}:@var{d}
1246 TCP connections will only be allowed from @var{host} on display @var{d}.
1247 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1248 be omitted in which case the server will accept connections from any host.
1250 @item unix:@var{path}
1252 Connections will be allowed over UNIX domain sockets where @var{path} is the
1253 location of a unix socket to listen for connections on.
1255 @item none
1257 VNC is initialized but not started. The monitor @code{change} command
1258 can be used to later start the VNC server.
1260 @end table
1262 Following the @var{display} value there may be one or more @var{option} flags
1263 separated by commas. Valid options are
1265 @table @option
1267 @item reverse
1269 Connect to a listening VNC client via a ``reverse'' connection. The
1270 client is specified by the @var{display}. For reverse network
1271 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1272 is a TCP port number, not a display number.
1274 @item websocket
1276 Opens an additional TCP listening port dedicated to VNC Websocket connections.
1277 By definition the Websocket port is 5700+@var{display}. If @var{host} is
1278 specified connections will only be allowed from this host.
1279 As an alternative the Websocket port could be specified by using
1280 @code{websocket}=@var{port}.
1281 If no TLS credentials are provided, the websocket connection runs in
1282 unencrypted mode. If TLS credentials are provided, the websocket connection
1283 requires encrypted client connections.
1285 @item password
1287 Require that password based authentication is used for client connections.
1289 The password must be set separately using the @code{set_password} command in
1290 the @ref{pcsys_monitor}. The syntax to change your password is:
1291 @code{set_password <protocol> <password>} where <protocol> could be either
1292 "vnc" or "spice".
1294 If you would like to change <protocol> password expiration, you should use
1295 @code{expire_password <protocol> <expiration-time>} where expiration time could
1296 be one of the following options: now, never, +seconds or UNIX time of
1297 expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1298 to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1299 date and time).
1301 You can also use keywords "now" or "never" for the expiration time to
1302 allow <protocol> password to expire immediately or never expire.
1304 @item tls-creds=@var{ID}
1306 Provides the ID of a set of TLS credentials to use to secure the
1307 VNC server. They will apply to both the normal VNC server socket
1308 and the websocket socket (if enabled). Setting TLS credentials
1309 will cause the VNC server socket to enable the VeNCrypt auth
1310 mechanism. The credentials should have been previously created
1311 using the @option{-object tls-creds} argument.
1313 The @option{tls-creds} parameter obsoletes the @option{tls},
1314 @option{x509}, and @option{x509verify} options, and as such
1315 it is not permitted to set both new and old type options at
1316 the same time.
1318 @item tls
1320 Require that client use TLS when communicating with the VNC server. This
1321 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1322 attack. It is recommended that this option be combined with either the
1323 @option{x509} or @option{x509verify} options.
1325 This option is now deprecated in favor of using the @option{tls-creds}
1326 argument.
1328 @item x509=@var{/path/to/certificate/dir}
1330 Valid if @option{tls} is specified. Require that x509 credentials are used
1331 for negotiating the TLS session. The server will send its x509 certificate
1332 to the client. It is recommended that a password be set on the VNC server
1333 to provide authentication of the client when this is used. The path following
1334 this option specifies where the x509 certificates are to be loaded from.
1335 See the @ref{vnc_security} section for details on generating certificates.
1337 This option is now deprecated in favour of using the @option{tls-creds}
1338 argument.
1340 @item x509verify=@var{/path/to/certificate/dir}
1342 Valid if @option{tls} is specified. Require that x509 credentials are used
1343 for negotiating the TLS session. The server will send its x509 certificate
1344 to the client, and request that the client send its own x509 certificate.
1345 The server will validate the client's certificate against the CA certificate,
1346 and reject clients when validation fails. If the certificate authority is
1347 trusted, this is a sufficient authentication mechanism. You may still wish
1348 to set a password on the VNC server as a second authentication layer. The
1349 path following this option specifies where the x509 certificates are to
1350 be loaded from. See the @ref{vnc_security} section for details on generating
1351 certificates.
1353 This option is now deprecated in favour of using the @option{tls-creds}
1354 argument.
1356 @item sasl
1358 Require that the client use SASL to authenticate with the VNC server.
1359 The exact choice of authentication method used is controlled from the
1360 system / user's SASL configuration file for the 'qemu' service. This
1361 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1362 unprivileged user, an environment variable SASL_CONF_PATH can be used
1363 to make it search alternate locations for the service config.
1364 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1365 it is recommended that SASL always be combined with the 'tls' and
1366 'x509' settings to enable use of SSL and server certificates. This
1367 ensures a data encryption preventing compromise of authentication
1368 credentials. See the @ref{vnc_security} section for details on using
1369 SASL authentication.
1371 @item acl
1373 Turn on access control lists for checking of the x509 client certificate
1374 and SASL party. For x509 certs, the ACL check is made against the
1375 certificate's distinguished name. This is something that looks like
1376 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1377 made against the username, which depending on the SASL plugin, may
1378 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1379 When the @option{acl} flag is set, the initial access list will be
1380 empty, with a @code{deny} policy. Thus no one will be allowed to
1381 use the VNC server until the ACLs have been loaded. This can be
1382 achieved using the @code{acl} monitor command.
1384 @item lossy
1386 Enable lossy compression methods (gradient, JPEG, ...). If this
1387 option is set, VNC client may receive lossy framebuffer updates
1388 depending on its encoding settings. Enabling this option can save
1389 a lot of bandwidth at the expense of quality.
1391 @item non-adaptive
1393 Disable adaptive encodings. Adaptive encodings are enabled by default.
1394 An adaptive encoding will try to detect frequently updated screen regions,
1395 and send updates in these regions using a lossy encoding (like JPEG).
1396 This can be really helpful to save bandwidth when playing videos. Disabling
1397 adaptive encodings restores the original static behavior of encodings
1398 like Tight.
1400 @item share=[allow-exclusive|force-shared|ignore]
1402 Set display sharing policy. 'allow-exclusive' allows clients to ask
1403 for exclusive access. As suggested by the rfb spec this is
1404 implemented by dropping other connections. Connecting multiple
1405 clients in parallel requires all clients asking for a shared session
1406 (vncviewer: -shared switch). This is the default. 'force-shared'
1407 disables exclusive client access. Useful for shared desktop sessions,
1408 where you don't want someone forgetting specify -shared disconnect
1409 everybody else. 'ignore' completely ignores the shared flag and
1410 allows everybody connect unconditionally. Doesn't conform to the rfb
1411 spec but is traditional QEMU behavior.
1413 @end table
1414 ETEXI
1416 STEXI
1417 @end table
1418 ETEXI
1419 ARCHHEADING(, QEMU_ARCH_I386)
1421 ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1422 STEXI
1423 @table @option
1424 ETEXI
1426 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1427 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1428 QEMU_ARCH_I386)
1429 STEXI
1430 @item -win2k-hack
1431 @findex -win2k-hack
1432 Use it when installing Windows 2000 to avoid a disk full bug. After
1433 Windows 2000 is installed, you no longer need this option (this option
1434 slows down the IDE transfers).
1435 ETEXI
1437 HXCOMM Deprecated by -rtc
1438 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1440 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1441 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1442 QEMU_ARCH_I386)
1443 STEXI
1444 @item -no-fd-bootchk
1445 @findex -no-fd-bootchk
1446 Disable boot signature checking for floppy disks in BIOS. May
1447 be needed to boot from old floppy disks.
1448 ETEXI
1450 DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1451 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1452 STEXI
1453 @item -no-acpi
1454 @findex -no-acpi
1455 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1456 it if your guest OS complains about ACPI problems (PC target machine
1457 only).
1458 ETEXI
1460 DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1461 "-no-hpet disable HPET\n", QEMU_ARCH_I386)
1462 STEXI
1463 @item -no-hpet
1464 @findex -no-hpet
1465 Disable HPET support.
1466 ETEXI
1468 DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1469 "-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"
1470 " ACPI table description\n", QEMU_ARCH_I386)
1471 STEXI
1472 @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}]...]
1473 @findex -acpitable
1474 Add ACPI table with specified header fields and context from specified files.
1475 For file=, take whole ACPI table from the specified files, including all
1476 ACPI headers (possible overridden by other options).
1477 For data=, only data
1478 portion of the table is used, all header information is specified in the
1479 command line.
1480 If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id
1481 fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order
1482 to ensure the field matches required by the Microsoft SLIC spec and the ACPI
1483 spec.
1484 ETEXI
1486 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1487 "-smbios file=binary\n"
1488 " load SMBIOS entry from binary file\n"
1489 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1490 " [,uefi=on|off]\n"
1491 " specify SMBIOS type 0 fields\n"
1492 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1493 " [,uuid=uuid][,sku=str][,family=str]\n"
1494 " specify SMBIOS type 1 fields\n"
1495 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1496 " [,asset=str][,location=str]\n"
1497 " specify SMBIOS type 2 fields\n"
1498 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n"
1499 " [,sku=str]\n"
1500 " specify SMBIOS type 3 fields\n"
1501 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n"
1502 " [,asset=str][,part=str]\n"
1503 " specify SMBIOS type 4 fields\n"
1504 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n"
1505 " [,asset=str][,part=str][,speed=%d]\n"
1506 " specify SMBIOS type 17 fields\n",
1507 QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1508 STEXI
1509 @item -smbios file=@var{binary}
1510 @findex -smbios
1511 Load SMBIOS entry from binary file.
1513 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1514 Specify SMBIOS type 0 fields
1516 @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}]
1517 Specify SMBIOS type 1 fields
1519 @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}]
1520 Specify SMBIOS type 2 fields
1522 @item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}]
1523 Specify SMBIOS type 3 fields
1525 @item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}]
1526 Specify SMBIOS type 4 fields
1528 @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}]
1529 Specify SMBIOS type 17 fields
1530 ETEXI
1532 STEXI
1533 @end table
1534 ETEXI
1535 DEFHEADING()
1537 DEFHEADING(Network options:)
1538 STEXI
1539 @table @option
1540 ETEXI
1542 HXCOMM Legacy slirp options (now moved to -net user):
1543 #ifdef CONFIG_SLIRP
1544 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1545 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1546 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1547 #ifndef _WIN32
1548 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1549 #endif
1550 #endif
1552 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1553 #ifdef CONFIG_SLIRP
1554 "-netdev user,id=str[,net=addr[/mask]][,host=addr][,ip6-net=addr[/int]]\n"
1555 " [,ip6-host=addr][,restrict=on|off][,hostname=host][,dhcpstart=addr]\n"
1556 " [,dns=addr][,ip6-dns=addr][,dnssearch=domain][,tftp=dir]\n"
1557 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1558 #ifndef _WIN32
1559 "[,smb=dir[,smbserver=addr]]\n"
1560 #endif
1561 " configure a user mode network backend with ID 'str',\n"
1562 " its DHCP server and optional services\n"
1563 #endif
1564 #ifdef _WIN32
1565 "-netdev tap,id=str,ifname=name\n"
1566 " configure a host TAP network backend with ID 'str'\n"
1567 #else
1568 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n"
1569 " [,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n"
1570 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n"
1571 " configure a host TAP network backend with ID 'str'\n"
1572 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1573 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1574 " to deconfigure it\n"
1575 " use '[down]script=no' to disable script execution\n"
1576 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1577 " configure it\n"
1578 " use 'fd=h' to connect to an already opened TAP interface\n"
1579 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n"
1580 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
1581 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
1582 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1583 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1584 " use vhost=on to enable experimental in kernel accelerator\n"
1585 " (only has effect for virtio guests which use MSIX)\n"
1586 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1587 " use 'vhostfd=h' to connect to an already opened vhost net device\n"
1588 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n"
1589 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n"
1590 "-netdev bridge,id=str[,br=bridge][,helper=helper]\n"
1591 " configure a host TAP network backend with ID 'str' that is\n"
1592 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1593 " using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n"
1594 #endif
1595 #ifdef __linux__
1596 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n"
1597 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n"
1598 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n"
1599 " [,rxcookie=rxcookie][,offset=offset]\n"
1600 " configure a network backend with ID 'str' connected to\n"
1601 " an Ethernet over L2TPv3 pseudowire.\n"
1602 " Linux kernel 3.3+ as well as most routers can talk\n"
1603 " L2TPv3. This transport allows connecting a VM to a VM,\n"
1604 " VM to a router and even VM to Host. It is a nearly-universal\n"
1605 " standard (RFC3391). Note - this implementation uses static\n"
1606 " pre-configured tunnels (same as the Linux kernel).\n"
1607 " use 'src=' to specify source address\n"
1608 " use 'dst=' to specify destination address\n"
1609 " use 'udp=on' to specify udp encapsulation\n"
1610 " use 'srcport=' to specify source udp port\n"
1611 " use 'dstport=' to specify destination udp port\n"
1612 " use 'ipv6=on' to force v6\n"
1613 " L2TPv3 uses cookies to prevent misconfiguration as\n"
1614 " well as a weak security measure\n"
1615 " use 'rxcookie=0x012345678' to specify a rxcookie\n"
1616 " use 'txcookie=0x012345678' to specify a txcookie\n"
1617 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n"
1618 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n"
1619 " use 'pincounter=on' to work around broken counter handling in peer\n"
1620 " use 'offset=X' to add an extra offset between header and data\n"
1621 #endif
1622 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n"
1623 " configure a network backend to connect to another network\n"
1624 " using a socket connection\n"
1625 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1626 " configure a network backend to connect to a multicast maddr and port\n"
1627 " use 'localaddr=addr' to specify the host address to send packets from\n"
1628 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
1629 " configure a network backend to connect to another network\n"
1630 " using an UDP tunnel\n"
1631 #ifdef CONFIG_VDE
1632 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1633 " configure a network backend to connect to port 'n' of a vde switch\n"
1634 " running on host and listening for incoming connections on 'socketpath'.\n"
1635 " Use group 'groupname' and mode 'octalmode' to change default\n"
1636 " ownership and permissions for communication port.\n"
1637 #endif
1638 #ifdef CONFIG_NETMAP
1639 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n"
1640 " attach to the existing netmap-enabled network interface 'name', or to a\n"
1641 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n"
1642 " netmap device, defaults to '/dev/netmap')\n"
1643 #endif
1644 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n"
1645 " configure a vhost-user network, backed by a chardev 'dev'\n"
1646 "-netdev hubport,id=str,hubid=n\n"
1647 " configure a hub port on QEMU VLAN 'n'\n", QEMU_ARCH_ALL)
1648 DEF("net", HAS_ARG, QEMU_OPTION_net,
1649 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
1650 " old way to create a new NIC and connect it to VLAN 'n'\n"
1651 " (use the '-device devtype,netdev=str' option if possible instead)\n"
1652 "-net dump[,vlan=n][,file=f][,len=n]\n"
1653 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n"
1654 "-net none use it alone to have zero network devices. If no -net option\n"
1655 " is provided, the default is '-net nic -net user'\n"
1656 "-net ["
1657 #ifdef CONFIG_SLIRP
1658 "user|"
1659 #endif
1660 "tap|"
1661 "bridge|"
1662 #ifdef CONFIG_VDE
1663 "vde|"
1664 #endif
1665 #ifdef CONFIG_NETMAP
1666 "netmap|"
1667 #endif
1668 "socket][,vlan=n][,option][,option][,...]\n"
1669 " old way to initialize a host network interface\n"
1670 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL)
1671 STEXI
1672 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1673 @findex -net
1674 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1675 = 0 is the default). The NIC is an e1000 by default on the PC
1676 target. Optionally, the MAC address can be changed to @var{mac}, the
1677 device address set to @var{addr} (PCI cards only),
1678 and a @var{name} can be assigned for use in monitor commands.
1679 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1680 that the card should have; this option currently only affects virtio cards; set
1681 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1682 NIC is created. QEMU can emulate several different models of network card.
1683 Valid values for @var{type} are
1684 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1685 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1686 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1687 Not all devices are supported on all targets. Use @code{-net nic,model=help}
1688 for a list of available devices for your target.
1690 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
1691 @findex -netdev
1692 @item -net user[,@var{option}][,@var{option}][,...]
1693 Use the user mode network stack which requires no administrator
1694 privilege to run. Valid options are:
1696 @table @option
1697 @item vlan=@var{n}
1698 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1700 @item id=@var{id}
1701 @itemx name=@var{name}
1702 Assign symbolic name for use in monitor commands.
1704 @item net=@var{addr}[/@var{mask}]
1705 Set IP network address the guest will see. Optionally specify the netmask,
1706 either in the form a.b.c.d or as number of valid top-most bits. Default is
1707 10.0.2.0/24.
1709 @item host=@var{addr}
1710 Specify the guest-visible address of the host. Default is the 2nd IP in the
1711 guest network, i.e. x.x.x.2.
1713 @item ip6-net=@var{addr}[/@var{int}]
1714 Set IPv6 network address the guest will see. Optionally specify the prefix
1715 size, as number of valid top-most bits. Default is fec0::/64.
1717 @item ip6-host=@var{addr}
1718 Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in
1719 the guest network, i.e. xxxx::2.
1721 @item restrict=on|off
1722 If this option is enabled, the guest will be isolated, i.e. it will not be
1723 able to contact the host and no guest IP packets will be routed over the host
1724 to the outside. This option does not affect any explicitly set forwarding rules.
1726 @item hostname=@var{name}
1727 Specifies the client hostname reported by the built-in DHCP server.
1729 @item dhcpstart=@var{addr}
1730 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1731 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1733 @item dns=@var{addr}
1734 Specify the guest-visible address of the virtual nameserver. The address must
1735 be different from the host address. Default is the 3rd IP in the guest network,
1736 i.e. x.x.x.3.
1738 @item ip6-dns=@var{addr}
1739 Specify the guest-visible address of the IPv6 virtual nameserver. The address
1740 must be different from the host address. Default is the 3rd IP in the guest
1741 network, i.e. xxxx::3.
1743 @item dnssearch=@var{domain}
1744 Provides an entry for the domain-search list sent by the built-in
1745 DHCP server. More than one domain suffix can be transmitted by specifying
1746 this option multiple times. If supported, this will cause the guest to
1747 automatically try to append the given domain suffix(es) in case a domain name
1748 can not be resolved.
1750 Example:
1751 @example
1752 qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
1753 @end example
1755 @item tftp=@var{dir}
1756 When using the user mode network stack, activate a built-in TFTP
1757 server. The files in @var{dir} will be exposed as the root of a TFTP server.
1758 The TFTP client on the guest must be configured in binary mode (use the command
1759 @code{bin} of the Unix TFTP client).
1761 @item bootfile=@var{file}
1762 When using the user mode network stack, broadcast @var{file} as the BOOTP
1763 filename. In conjunction with @option{tftp}, this can be used to network boot
1764 a guest from a local directory.
1766 Example (using pxelinux):
1767 @example
1768 qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1769 @end example
1771 @item smb=@var{dir}[,smbserver=@var{addr}]
1772 When using the user mode network stack, activate a built-in SMB
1773 server so that Windows OSes can access to the host files in @file{@var{dir}}
1774 transparently. The IP address of the SMB server can be set to @var{addr}. By
1775 default the 4th IP in the guest network is used, i.e. x.x.x.4.
1777 In the guest Windows OS, the line:
1778 @example
1779 10.0.2.4 smbserver
1780 @end example
1781 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1782 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1784 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
1786 Note that a SAMBA server must be installed on the host OS.
1787 QEMU was tested successfully with smbd versions from Red Hat 9,
1788 Fedora Core 3 and OpenSUSE 11.x.
1790 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1791 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1792 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1793 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1794 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1795 be bound to a specific host interface. If no connection type is set, TCP is
1796 used. This option can be given multiple times.
1798 For example, to redirect host X11 connection from screen 1 to guest
1799 screen 0, use the following:
1801 @example
1802 # on the host
1803 qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1804 # this host xterm should open in the guest X11 server
1805 xterm -display :1
1806 @end example
1808 To redirect telnet connections from host port 5555 to telnet port on
1809 the guest, use the following:
1811 @example
1812 # on the host
1813 qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
1814 telnet localhost 5555
1815 @end example
1817 Then when you use on the host @code{telnet localhost 5555}, you
1818 connect to the guest telnet server.
1820 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1821 @itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
1822 Forward guest TCP connections to the IP address @var{server} on port @var{port}
1823 to the character device @var{dev} or to a program executed by @var{cmd:command}
1824 which gets spawned for each connection. This option can be given multiple times.
1826 You can either use a chardev directly and have that one used throughout QEMU's
1827 lifetime, like in the following example:
1829 @example
1830 # open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
1831 # the guest accesses it
1832 qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...]
1833 @end example
1835 Or you can execute a command on every TCP connection established by the guest,
1836 so that QEMU behaves similar to an inetd process for that virtual server:
1838 @example
1839 # call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
1840 # and connect the TCP stream to its stdin/stdout
1841 qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
1842 @end example
1844 @end table
1846 Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
1847 processed and applied to -net user. Mixing them with the new configuration
1848 syntax gives undefined results. Their use for new applications is discouraged
1849 as they will be removed from future versions.
1851 @item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1852 @itemx -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1853 Connect the host TAP network interface @var{name} to VLAN @var{n}.
1855 Use the network script @var{file} to configure it and the network script
1856 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
1857 automatically provides one. The default network configure script is
1858 @file{/etc/qemu-ifup} and the default network deconfigure script is
1859 @file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
1860 to disable script execution.
1862 If running QEMU as an unprivileged user, use the network helper
1863 @var{helper} to configure the TAP interface. The default network
1864 helper executable is @file{/path/to/qemu-bridge-helper}.
1866 @option{fd}=@var{h} can be used to specify the handle of an already
1867 opened host TAP interface.
1869 Examples:
1871 @example
1872 #launch a QEMU instance with the default network script
1873 qemu-system-i386 linux.img -net nic -net tap
1874 @end example
1876 @example
1877 #launch a QEMU instance with two NICs, each one connected
1878 #to a TAP device
1879 qemu-system-i386 linux.img \
1880 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
1881 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
1882 @end example
1884 @example
1885 #launch a QEMU instance with the default network helper to
1886 #connect a TAP device to bridge br0
1887 qemu-system-i386 linux.img \
1888 -net nic -net tap,"helper=/path/to/qemu-bridge-helper"
1889 @end example
1891 @item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
1892 @itemx -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
1893 Connect a host TAP network interface to a host bridge device.
1895 Use the network helper @var{helper} to configure the TAP interface and
1896 attach it to the bridge. The default network helper executable is
1897 @file{/path/to/qemu-bridge-helper} and the default bridge
1898 device is @file{br0}.
1900 Examples:
1902 @example
1903 #launch a QEMU instance with the default network helper to
1904 #connect a TAP device to bridge br0
1905 qemu-system-i386 linux.img -net bridge -net nic,model=virtio
1906 @end example
1908 @example
1909 #launch a QEMU instance with the default network helper to
1910 #connect a TAP device to bridge qemubr0
1911 qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
1912 @end example
1914 @item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1915 @itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1917 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
1918 machine using a TCP socket connection. If @option{listen} is
1919 specified, QEMU waits for incoming connections on @var{port}
1920 (@var{host} is optional). @option{connect} is used to connect to
1921 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
1922 specifies an already opened TCP socket.
1924 Example:
1925 @example
1926 # launch a first QEMU instance
1927 qemu-system-i386 linux.img \
1928 -net nic,macaddr=52:54:00:12:34:56 \
1929 -net socket,listen=:1234
1930 # connect the VLAN 0 of this instance to the VLAN 0
1931 # of the first instance
1932 qemu-system-i386 linux.img \
1933 -net nic,macaddr=52:54:00:12:34:57 \
1934 -net socket,connect=127.0.0.1:1234
1935 @end example
1937 @item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1938 @itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1940 Create a VLAN @var{n} shared with another QEMU virtual
1941 machines using a UDP multicast socket, effectively making a bus for
1942 every QEMU with same multicast address @var{maddr} and @var{port}.
1943 NOTES:
1944 @enumerate
1945 @item
1946 Several QEMU can be running on different hosts and share same bus (assuming
1947 correct multicast setup for these hosts).
1948 @item
1949 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
1950 @url{http://user-mode-linux.sf.net}.
1951 @item
1952 Use @option{fd=h} to specify an already opened UDP multicast socket.
1953 @end enumerate
1955 Example:
1956 @example
1957 # launch one QEMU instance
1958 qemu-system-i386 linux.img \
1959 -net nic,macaddr=52:54:00:12:34:56 \
1960 -net socket,mcast=230.0.0.1:1234
1961 # launch another QEMU instance on same "bus"
1962 qemu-system-i386 linux.img \
1963 -net nic,macaddr=52:54:00:12:34:57 \
1964 -net socket,mcast=230.0.0.1:1234
1965 # launch yet another QEMU instance on same "bus"
1966 qemu-system-i386 linux.img \
1967 -net nic,macaddr=52:54:00:12:34:58 \
1968 -net socket,mcast=230.0.0.1:1234
1969 @end example
1971 Example (User Mode Linux compat.):
1972 @example
1973 # launch QEMU instance (note mcast address selected
1974 # is UML's default)
1975 qemu-system-i386 linux.img \
1976 -net nic,macaddr=52:54:00:12:34:56 \
1977 -net socket,mcast=239.192.168.1:1102
1978 # launch UML
1979 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
1980 @end example
1982 Example (send packets from host's 1.2.3.4):
1983 @example
1984 qemu-system-i386 linux.img \
1985 -net nic,macaddr=52:54:00:12:34:56 \
1986 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
1987 @end example
1989 @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}]
1990 @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}]
1991 Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular
1992 protocol to transport Ethernet (and other Layer 2) data frames between
1993 two systems. It is present in routers, firewalls and the Linux kernel
1994 (from version 3.3 onwards).
1996 This transport allows a VM to communicate to another VM, router or firewall directly.
1998 @item src=@var{srcaddr}
1999 source address (mandatory)
2000 @item dst=@var{dstaddr}
2001 destination address (mandatory)
2002 @item udp
2003 select udp encapsulation (default is ip).
2004 @item srcport=@var{srcport}
2005 source udp port.
2006 @item dstport=@var{dstport}
2007 destination udp port.
2008 @item ipv6
2009 force v6, otherwise defaults to v4.
2010 @item rxcookie=@var{rxcookie}
2011 @itemx txcookie=@var{txcookie}
2012 Cookies are a weak form of security in the l2tpv3 specification.
2013 Their function is mostly to prevent misconfiguration. By default they are 32
2014 bit.
2015 @item cookie64
2016 Set cookie size to 64 bit instead of the default 32
2017 @item counter=off
2018 Force a 'cut-down' L2TPv3 with no counter as in
2019 draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00
2020 @item pincounter=on
2021 Work around broken counter handling in peer. This may also help on
2022 networks which have packet reorder.
2023 @item offset=@var{offset}
2024 Add an extra offset between header and data
2026 For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan
2027 on the remote Linux host 1.2.3.4:
2028 @example
2029 # Setup tunnel on linux host using raw ip as encapsulation
2030 # on 1.2.3.4
2031 ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \
2032 encap udp udp_sport 16384 udp_dport 16384
2033 ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \
2034 0xFFFFFFFF peer_session_id 0xFFFFFFFF
2035 ifconfig vmtunnel0 mtu 1500
2036 ifconfig vmtunnel0 up
2037 brctl addif br-lan vmtunnel0
2040 # on 4.3.2.1
2041 # launch QEMU instance - if your network has reorder or is very lossy add ,pincounter
2043 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
2046 @end example
2048 @item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2049 @itemx -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2050 Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
2051 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
2052 and MODE @var{octalmode} to change default ownership and permissions for
2053 communication port. This option is only available if QEMU has been compiled
2054 with vde support enabled.
2056 Example:
2057 @example
2058 # launch vde switch
2059 vde_switch -F -sock /tmp/myswitch
2060 # launch QEMU instance
2061 qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch
2062 @end example
2064 @item -netdev hubport,id=@var{id},hubid=@var{hubid}
2066 Create a hub port on QEMU "vlan" @var{hubid}.
2068 The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single
2069 netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the
2070 required hub automatically.
2072 @item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n]
2074 Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should
2075 be a unix domain socket backed one. The vhost-user uses a specifically defined
2076 protocol to pass vhost ioctl replacement messages to an application on the other
2077 end of the socket. On non-MSIX guests, the feature can be forced with
2078 @var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to
2079 be created for multiqueue vhost-user.
2081 Example:
2082 @example
2083 qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \
2084 -numa node,memdev=mem \
2085 -chardev socket,path=/path/to/socket \
2086 -netdev type=vhost-user,id=net0,chardev=chr0 \
2087 -device virtio-net-pci,netdev=net0
2088 @end example
2090 @item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
2091 Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
2092 At most @var{len} bytes (64k by default) per packet are stored. The file format is
2093 libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
2094 Note: For devices created with '-netdev', use '-object filter-dump,...' instead.
2096 @item -net none
2097 Indicate that no network devices should be configured. It is used to
2098 override the default configuration (@option{-net nic -net user}) which
2099 is activated if no @option{-net} options are provided.
2100 ETEXI
2102 STEXI
2103 @end table
2104 ETEXI
2105 DEFHEADING()
2107 DEFHEADING(Character device options:)
2108 STEXI
2110 The general form of a character device option is:
2111 @table @option
2112 ETEXI
2114 DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
2115 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2116 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
2117 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n"
2118 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n"
2119 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n"
2120 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n"
2121 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
2122 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
2123 " [,logfile=PATH][,logappend=on|off]\n"
2124 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2125 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
2126 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2127 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n"
2128 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2129 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2130 #ifdef _WIN32
2131 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2132 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2133 #else
2134 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2135 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n"
2136 #endif
2137 #ifdef CONFIG_BRLAPI
2138 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2139 #endif
2140 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
2141 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
2142 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2143 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2144 #endif
2145 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
2146 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2147 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2148 #endif
2149 #if defined(CONFIG_SPICE)
2150 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2151 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2152 #endif
2153 , QEMU_ARCH_ALL
2156 STEXI
2157 @item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
2158 @findex -chardev
2159 Backend is one of:
2160 @option{null},
2161 @option{socket},
2162 @option{udp},
2163 @option{msmouse},
2164 @option{vc},
2165 @option{ringbuf},
2166 @option{file},
2167 @option{pipe},
2168 @option{console},
2169 @option{serial},
2170 @option{pty},
2171 @option{stdio},
2172 @option{braille},
2173 @option{tty},
2174 @option{parallel},
2175 @option{parport},
2176 @option{spicevmc}.
2177 @option{spiceport}.
2178 The specific backend will determine the applicable options.
2180 All devices must have an id, which can be any string up to 127 characters long.
2181 It is used to uniquely identify this device in other command line directives.
2183 A character device may be used in multiplexing mode by multiple front-ends.
2184 Specify @option{mux=on} to enable this mode.
2185 A multiplexer is a "1:N" device, and here the "1" end is your specified chardev
2186 backend, and the "N" end is the various parts of QEMU that can talk to a chardev.
2187 If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will
2188 create a multiplexer with your specified ID, and you can then configure multiple
2189 front ends to use that chardev ID for their input/output. Up to four different
2190 front ends can be connected to a single multiplexed chardev. (Without
2191 multiplexing enabled, a chardev can only be used by a single front end.)
2192 For instance you could use this to allow a single stdio chardev to be used by
2193 two serial ports and the QEMU monitor:
2195 @example
2196 -chardev stdio,mux=on,id=char0 \
2197 -mon chardev=char0,mode=readline,default \
2198 -serial chardev:char0 \
2199 -serial chardev:char0
2200 @end example
2202 You can have more than one multiplexer in a system configuration; for instance
2203 you could have a TCP port multiplexed between UART 0 and UART 1, and stdio
2204 multiplexed between the QEMU monitor and a parallel port:
2206 @example
2207 -chardev stdio,mux=on,id=char0 \
2208 -mon chardev=char0,mode=readline,default \
2209 -parallel chardev:char0 \
2210 -chardev tcp,...,mux=on,id=char1 \
2211 -serial chardev:char1 \
2212 -serial chardev:char1
2213 @end example
2215 When you're using a multiplexed character device, some escape sequences are
2216 interpreted in the input. @xref{mux_keys, Keys in the character backend
2217 multiplexer}.
2219 Note that some other command line options may implicitly create multiplexed
2220 character backends; for instance @option{-serial mon:stdio} creates a
2221 multiplexed stdio backend connected to the serial port and the QEMU monitor,
2222 and @option{-nographic} also multiplexes the console and the monitor to
2223 stdio.
2225 There is currently no support for multiplexing in the other direction
2226 (where a single QEMU front end takes input and output from multiple chardevs).
2228 Every backend supports the @option{logfile} option, which supplies the path
2229 to a file to record all data transmitted via the backend. The @option{logappend}
2230 option controls whether the log file will be truncated or appended to when
2231 opened.
2233 Further options to each backend are described below.
2235 @item -chardev null ,id=@var{id}
2236 A void device. This device will not emit any data, and will drop any data it
2237 receives. The null backend does not take any options.
2239 @item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}] [,tls-creds=@var{id}]
2241 Create a two-way stream socket, which can be either a TCP or a unix socket. A
2242 unix socket will be created if @option{path} is specified. Behaviour is
2243 undefined if TCP options are specified for a unix socket.
2245 @option{server} specifies that the socket shall be a listening socket.
2247 @option{nowait} specifies that QEMU should not block waiting for a client to
2248 connect to a listening socket.
2250 @option{telnet} specifies that traffic on the socket should interpret telnet
2251 escape sequences.
2253 @option{reconnect} sets the timeout for reconnecting on non-server sockets when
2254 the remote end goes away. qemu will delay this many seconds and then attempt
2255 to reconnect. Zero disables reconnecting, and is the default.
2257 @option{tls-creds} requests enablement of the TLS protocol for encryption,
2258 and specifies the id of the TLS credentials to use for the handshake. The
2259 credentials must be previously created with the @option{-object tls-creds}
2260 argument.
2262 TCP and unix socket options are given below:
2264 @table @option
2266 @item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
2268 @option{host} for a listening socket specifies the local address to be bound.
2269 For a connecting socket species the remote host to connect to. @option{host} is
2270 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
2272 @option{port} for a listening socket specifies the local port to be bound. For a
2273 connecting socket specifies the port on the remote host to connect to.
2274 @option{port} can be given as either a port number or a service name.
2275 @option{port} is required.
2277 @option{to} is only relevant to listening sockets. If it is specified, and
2278 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
2279 to and including @option{to} until it succeeds. @option{to} must be specified
2280 as a port number.
2282 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2283 If neither is specified the socket may use either protocol.
2285 @option{nodelay} disables the Nagle algorithm.
2287 @item unix options: path=@var{path}
2289 @option{path} specifies the local path of the unix socket. @option{path} is
2290 required.
2292 @end table
2294 @item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
2296 Sends all traffic from the guest to a remote host over UDP.
2298 @option{host} specifies the remote host to connect to. If not specified it
2299 defaults to @code{localhost}.
2301 @option{port} specifies the port on the remote host to connect to. @option{port}
2302 is required.
2304 @option{localaddr} specifies the local address to bind to. If not specified it
2305 defaults to @code{0.0.0.0}.
2307 @option{localport} specifies the local port to bind to. If not specified any
2308 available local port will be used.
2310 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2311 If neither is specified the device may use either protocol.
2313 @item -chardev msmouse ,id=@var{id}
2315 Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
2316 take any options.
2318 @item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
2320 Connect to a QEMU text console. @option{vc} may optionally be given a specific
2321 size.
2323 @option{width} and @option{height} specify the width and height respectively of
2324 the console, in pixels.
2326 @option{cols} and @option{rows} specify that the console be sized to fit a text
2327 console with the given dimensions.
2329 @item -chardev ringbuf ,id=@var{id} [,size=@var{size}]
2331 Create a ring buffer with fixed size @option{size}.
2332 @var{size} must be a power of two, and defaults to @code{64K}).
2334 @item -chardev file ,id=@var{id} ,path=@var{path}
2336 Log all traffic received from the guest to a file.
2338 @option{path} specifies the path of the file to be opened. This file will be
2339 created if it does not already exist, and overwritten if it does. @option{path}
2340 is required.
2342 @item -chardev pipe ,id=@var{id} ,path=@var{path}
2344 Create a two-way connection to the guest. The behaviour differs slightly between
2345 Windows hosts and other hosts:
2347 On Windows, a single duplex pipe will be created at
2348 @file{\\.pipe\@option{path}}.
2350 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
2351 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
2352 received by the guest. Data written by the guest can be read from
2353 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
2354 be present.
2356 @option{path} forms part of the pipe path as described above. @option{path} is
2357 required.
2359 @item -chardev console ,id=@var{id}
2361 Send traffic from the guest to QEMU's standard output. @option{console} does not
2362 take any options.
2364 @option{console} is only available on Windows hosts.
2366 @item -chardev serial ,id=@var{id} ,path=@option{path}
2368 Send traffic from the guest to a serial device on the host.
2370 On Unix hosts serial will actually accept any tty device,
2371 not only serial lines.
2373 @option{path} specifies the name of the serial device to open.
2375 @item -chardev pty ,id=@var{id}
2377 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2378 not take any options.
2380 @option{pty} is not available on Windows hosts.
2382 @item -chardev stdio ,id=@var{id} [,signal=on|off]
2383 Connect to standard input and standard output of the QEMU process.
2385 @option{signal} controls if signals are enabled on the terminal, that includes
2386 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2387 default, use @option{signal=off} to disable it.
2389 @option{stdio} is not available on Windows hosts.
2391 @item -chardev braille ,id=@var{id}
2393 Connect to a local BrlAPI server. @option{braille} does not take any options.
2395 @item -chardev tty ,id=@var{id} ,path=@var{path}
2397 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2398 DragonFlyBSD hosts. It is an alias for @option{serial}.
2400 @option{path} specifies the path to the tty. @option{path} is required.
2402 @item -chardev parallel ,id=@var{id} ,path=@var{path}
2403 @itemx -chardev parport ,id=@var{id} ,path=@var{path}
2405 @option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2407 Connect to a local parallel port.
2409 @option{path} specifies the path to the parallel port device. @option{path} is
2410 required.
2412 @item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2414 @option{spicevmc} is only available when spice support is built in.
2416 @option{debug} debug level for spicevmc
2418 @option{name} name of spice channel to connect to
2420 Connect to a spice virtual machine channel, such as vdiport.
2422 @item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2424 @option{spiceport} is only available when spice support is built in.
2426 @option{debug} debug level for spicevmc
2428 @option{name} name of spice port to connect to
2430 Connect to a spice port, allowing a Spice client to handle the traffic
2431 identified by a name (preferably a fqdn).
2432 ETEXI
2434 STEXI
2435 @end table
2436 ETEXI
2437 DEFHEADING()
2439 DEFHEADING(Device URL Syntax:)
2440 STEXI
2442 In addition to using normal file images for the emulated storage devices,
2443 QEMU can also use networked resources such as iSCSI devices. These are
2444 specified using a special URL syntax.
2446 @table @option
2447 @item iSCSI
2448 iSCSI support allows QEMU to access iSCSI resources directly and use as
2449 images for the guest storage. Both disk and cdrom images are supported.
2451 Syntax for specifying iSCSI LUNs is
2452 ``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
2454 By default qemu will use the iSCSI initiator-name
2455 'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command
2456 line or a configuration file.
2458 Since version Qemu 2.4 it is possible to specify a iSCSI request timeout to detect
2459 stalled requests and force a reestablishment of the session. The timeout
2460 is specified in seconds. The default is 0 which means no timeout. Libiscsi
2461 1.15.0 or greater is required for this feature.
2463 Example (without authentication):
2464 @example
2465 qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
2466 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
2467 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2468 @end example
2470 Example (CHAP username/password via URL):
2471 @example
2472 qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
2473 @end example
2475 Example (CHAP username/password via environment variables):
2476 @example
2477 LIBISCSI_CHAP_USERNAME="user" \
2478 LIBISCSI_CHAP_PASSWORD="password" \
2479 qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2480 @end example
2482 iSCSI support is an optional feature of QEMU and only available when
2483 compiled and linked against libiscsi.
2484 ETEXI
2485 DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
2486 "-iscsi [user=user][,password=password]\n"
2487 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
2488 " [,initiator-name=initiator-iqn][,id=target-iqn]\n"
2489 " [,timeout=timeout]\n"
2490 " iSCSI session parameters\n", QEMU_ARCH_ALL)
2491 STEXI
2493 iSCSI parameters such as username and password can also be specified via
2494 a configuration file. See qemu-doc for more information and examples.
2496 @item NBD
2497 QEMU supports NBD (Network Block Devices) both using TCP protocol as well
2498 as Unix Domain Sockets.
2500 Syntax for specifying a NBD device using TCP
2501 ``nbd:<server-ip>:<port>[:exportname=<export>]''
2503 Syntax for specifying a NBD device using Unix Domain Sockets
2504 ``nbd:unix:<domain-socket>[:exportname=<export>]''
2507 Example for TCP
2508 @example
2509 qemu-system-i386 --drive file=nbd:192.0.2.1:30000
2510 @end example
2512 Example for Unix Domain Sockets
2513 @example
2514 qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket
2515 @end example
2517 @item SSH
2518 QEMU supports SSH (Secure Shell) access to remote disks.
2520 Examples:
2521 @example
2522 qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img
2523 qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img
2524 @end example
2526 Currently authentication must be done using ssh-agent. Other
2527 authentication methods may be supported in future.
2529 @item Sheepdog
2530 Sheepdog is a distributed storage system for QEMU.
2531 QEMU supports using either local sheepdog devices or remote networked
2532 devices.
2534 Syntax for specifying a sheepdog device
2535 @example
2536 sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag]
2537 @end example
2539 Example
2540 @example
2541 qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine
2542 @end example
2544 See also @url{http://http://www.osrg.net/sheepdog/}.
2546 @item GlusterFS
2547 GlusterFS is an user space distributed file system.
2548 QEMU supports the use of GlusterFS volumes for hosting VM disk images using
2549 TCP, Unix Domain Sockets and RDMA transport protocols.
2551 Syntax for specifying a VM disk image on GlusterFS volume is
2552 @example
2553 gluster[+transport]://[server[:port]]/volname/image[?socket=...]
2554 @end example
2557 Example
2558 @example
2559 qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img
2560 @end example
2562 See also @url{http://www.gluster.org}.
2564 @item HTTP/HTTPS/FTP/FTPS/TFTP
2565 QEMU supports read-only access to files accessed over http(s), ftp(s) and tftp.
2567 Syntax using a single filename:
2568 @example
2569 <protocol>://[<username>[:<password>]@@]<host>/<path>
2570 @end example
2572 where:
2573 @table @option
2574 @item protocol
2575 'http', 'https', 'ftp', 'ftps', or 'tftp'.
2577 @item username
2578 Optional username for authentication to the remote server.
2580 @item password
2581 Optional password for authentication to the remote server.
2583 @item host
2584 Address of the remote server.
2586 @item path
2587 Path on the remote server, including any query string.
2588 @end table
2590 The following options are also supported:
2591 @table @option
2592 @item url
2593 The full URL when passing options to the driver explicitly.
2595 @item readahead
2596 The amount of data to read ahead with each range request to the remote server.
2597 This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it
2598 does not have a suffix, it will be assumed to be in bytes. The value must be a
2599 multiple of 512 bytes. It defaults to 256k.
2601 @item sslverify
2602 Whether to verify the remote server's certificate when connecting over SSL. It
2603 can have the value 'on' or 'off'. It defaults to 'on'.
2605 @item cookie
2606 Send this cookie (it can also be a list of cookies separated by ';') with
2607 each outgoing request. Only supported when using protocols such as HTTP
2608 which support cookies, otherwise ignored.
2610 @item timeout
2611 Set the timeout in seconds of the CURL connection. This timeout is the time
2612 that CURL waits for a response from the remote server to get the size of the
2613 image to be downloaded. If not set, the default timeout of 5 seconds is used.
2614 @end table
2616 Note that when passing options to qemu explicitly, @option{driver} is the value
2617 of <protocol>.
2619 Example: boot from a remote Fedora 20 live ISO image
2620 @example
2621 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
2623 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
2624 @end example
2626 Example: boot from a remote Fedora 20 cloud image using a local overlay for
2627 writes, copy-on-read, and a readahead of 64k
2628 @example
2629 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
2631 qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on
2632 @end example
2634 Example: boot from an image stored on a VMware vSphere server with a self-signed
2635 certificate using a local overlay for writes, a readahead of 64k and a timeout
2636 of 10 seconds.
2637 @example
2638 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
2640 qemu-system-x86_64 -drive file=/tmp/test.qcow2
2641 @end example
2642 ETEXI
2644 STEXI
2645 @end table
2646 ETEXI
2648 DEFHEADING(Bluetooth(R) options:)
2649 STEXI
2650 @table @option
2651 ETEXI
2653 DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
2654 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \
2655 "-bt hci,host[:id]\n" \
2656 " use host's HCI with the given name\n" \
2657 "-bt hci[,vlan=n]\n" \
2658 " emulate a standard HCI in virtual scatternet 'n'\n" \
2659 "-bt vhci[,vlan=n]\n" \
2660 " add host computer to virtual scatternet 'n' using VHCI\n" \
2661 "-bt device:dev[,vlan=n]\n" \
2662 " emulate a bluetooth device 'dev' in scatternet 'n'\n",
2663 QEMU_ARCH_ALL)
2664 STEXI
2665 @item -bt hci[...]
2666 @findex -bt
2667 Defines the function of the corresponding Bluetooth HCI. -bt options
2668 are matched with the HCIs present in the chosen machine type. For
2669 example when emulating a machine with only one HCI built into it, only
2670 the first @code{-bt hci[...]} option is valid and defines the HCI's
2671 logic. The Transport Layer is decided by the machine type. Currently
2672 the machines @code{n800} and @code{n810} have one HCI and all other
2673 machines have none.
2675 @anchor{bt-hcis}
2676 The following three types are recognized:
2678 @table @option
2679 @item -bt hci,null
2680 (default) The corresponding Bluetooth HCI assumes no internal logic
2681 and will not respond to any HCI commands or emit events.
2683 @item -bt hci,host[:@var{id}]
2684 (@code{bluez} only) The corresponding HCI passes commands / events
2685 to / from the physical HCI identified by the name @var{id} (default:
2686 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
2687 capable systems like Linux.
2689 @item -bt hci[,vlan=@var{n}]
2690 Add a virtual, standard HCI that will participate in the Bluetooth
2691 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
2692 VLANs, devices inside a bluetooth network @var{n} can only communicate
2693 with other devices in the same network (scatternet).
2694 @end table
2696 @item -bt vhci[,vlan=@var{n}]
2697 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2698 to the host bluetooth stack instead of to the emulated target. This
2699 allows the host and target machines to participate in a common scatternet
2700 and communicate. Requires the Linux @code{vhci} driver installed. Can
2701 be used as following:
2703 @example
2704 qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2705 @end example
2707 @item -bt device:@var{dev}[,vlan=@var{n}]
2708 Emulate a bluetooth device @var{dev} and place it in network @var{n}
2709 (default @code{0}). QEMU can only emulate one type of bluetooth devices
2710 currently:
2712 @table @option
2713 @item keyboard
2714 Virtual wireless keyboard implementing the HIDP bluetooth profile.
2715 @end table
2716 ETEXI
2718 STEXI
2719 @end table
2720 ETEXI
2721 DEFHEADING()
2723 #ifdef CONFIG_TPM
2724 DEFHEADING(TPM device options:)
2726 DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
2727 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
2728 " use path to provide path to a character device; default is /dev/tpm0\n"
2729 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
2730 " not provided it will be searched for in /sys/class/misc/tpm?/device\n",
2731 QEMU_ARCH_ALL)
2732 STEXI
2734 The general form of a TPM device option is:
2735 @table @option
2737 @item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
2738 @findex -tpmdev
2739 Backend type must be:
2740 @option{passthrough}.
2742 The specific backend type will determine the applicable options.
2743 The @code{-tpmdev} option creates the TPM backend and requires a
2744 @code{-device} option that specifies the TPM frontend interface model.
2746 Options to each backend are described below.
2748 Use 'help' to print all available TPM backend types.
2749 @example
2750 qemu -tpmdev help
2751 @end example
2753 @item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path}
2755 (Linux-host only) Enable access to the host's TPM using the passthrough
2756 driver.
2758 @option{path} specifies the path to the host's TPM device, i.e., on
2759 a Linux host this would be @code{/dev/tpm0}.
2760 @option{path} is optional and by default @code{/dev/tpm0} is used.
2762 @option{cancel-path} specifies the path to the host TPM device's sysfs
2763 entry allowing for cancellation of an ongoing TPM command.
2764 @option{cancel-path} is optional and by default QEMU will search for the
2765 sysfs entry to use.
2767 Some notes about using the host's TPM with the passthrough driver:
2769 The TPM device accessed by the passthrough driver must not be
2770 used by any other application on the host.
2772 Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
2773 the VM's firmware (BIOS/UEFI) will not be able to initialize the
2774 TPM again and may therefore not show a TPM-specific menu that would
2775 otherwise allow the user to configure the TPM, e.g., allow the user to
2776 enable/disable or activate/deactivate the TPM.
2777 Further, if TPM ownership is released from within a VM then the host's TPM
2778 will get disabled and deactivated. To enable and activate the
2779 TPM again afterwards, the host has to be rebooted and the user is
2780 required to enter the firmware's menu to enable and activate the TPM.
2781 If the TPM is left disabled and/or deactivated most TPM commands will fail.
2783 To create a passthrough TPM use the following two options:
2784 @example
2785 -tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
2786 @end example
2787 Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
2788 @code{tpmdev=tpm0} in the device option.
2790 @end table
2792 ETEXI
2794 DEFHEADING()
2796 #endif
2798 DEFHEADING(Linux/Multiboot boot specific:)
2799 STEXI
2801 When using these options, you can use a given Linux or Multiboot
2802 kernel without installing it in the disk image. It can be useful
2803 for easier testing of various kernels.
2805 @table @option
2806 ETEXI
2808 DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
2809 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL)
2810 STEXI
2811 @item -kernel @var{bzImage}
2812 @findex -kernel
2813 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2814 or in multiboot format.
2815 ETEXI
2817 DEF("append", HAS_ARG, QEMU_OPTION_append, \
2818 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL)
2819 STEXI
2820 @item -append @var{cmdline}
2821 @findex -append
2822 Use @var{cmdline} as kernel command line
2823 ETEXI
2825 DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
2826 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL)
2827 STEXI
2828 @item -initrd @var{file}
2829 @findex -initrd
2830 Use @var{file} as initial ram disk.
2832 @item -initrd "@var{file1} arg=foo,@var{file2}"
2834 This syntax is only available with multiboot.
2836 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
2837 first module.
2838 ETEXI
2840 DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
2841 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL)
2842 STEXI
2843 @item -dtb @var{file}
2844 @findex -dtb
2845 Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
2846 on boot.
2847 ETEXI
2849 STEXI
2850 @end table
2851 ETEXI
2852 DEFHEADING()
2854 DEFHEADING(Debug/Expert options:)
2855 STEXI
2856 @table @option
2857 ETEXI
2859 DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg,
2860 "-fw_cfg [name=]<name>,file=<file>\n"
2861 " add named fw_cfg entry from file\n"
2862 "-fw_cfg [name=]<name>,string=<str>\n"
2863 " add named fw_cfg entry from string\n",
2864 QEMU_ARCH_ALL)
2865 STEXI
2866 @item -fw_cfg [name=]@var{name},file=@var{file}
2867 @findex -fw_cfg
2868 Add named fw_cfg entry from file. @var{name} determines the name of
2869 the entry in the fw_cfg file directory exposed to the guest.
2871 @item -fw_cfg [name=]@var{name},string=@var{str}
2872 Add named fw_cfg entry from string.
2873 ETEXI
2875 DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
2876 "-serial dev redirect the serial port to char device 'dev'\n",
2877 QEMU_ARCH_ALL)
2878 STEXI
2879 @item -serial @var{dev}
2880 @findex -serial
2881 Redirect the virtual serial port to host character device
2882 @var{dev}. The default device is @code{vc} in graphical mode and
2883 @code{stdio} in non graphical mode.
2885 This option can be used several times to simulate up to 4 serial
2886 ports.
2888 Use @code{-serial none} to disable all serial ports.
2890 Available character devices are:
2891 @table @option
2892 @item vc[:@var{W}x@var{H}]
2893 Virtual console. Optionally, a width and height can be given in pixel with
2894 @example
2895 vc:800x600
2896 @end example
2897 It is also possible to specify width or height in characters:
2898 @example
2899 vc:80Cx24C
2900 @end example
2901 @item pty
2902 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
2903 @item none
2904 No device is allocated.
2905 @item null
2906 void device
2907 @item chardev:@var{id}
2908 Use a named character device defined with the @code{-chardev} option.
2909 @item /dev/XXX
2910 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
2911 parameters are set according to the emulated ones.
2912 @item /dev/parport@var{N}
2913 [Linux only, parallel port only] Use host parallel port
2914 @var{N}. Currently SPP and EPP parallel port features can be used.
2915 @item file:@var{filename}
2916 Write output to @var{filename}. No character can be read.
2917 @item stdio
2918 [Unix only] standard input/output
2919 @item pipe:@var{filename}
2920 name pipe @var{filename}
2921 @item COM@var{n}
2922 [Windows only] Use host serial port @var{n}
2923 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
2924 This implements UDP Net Console.
2925 When @var{remote_host} or @var{src_ip} are not specified
2926 they default to @code{0.0.0.0}.
2927 When not using a specified @var{src_port} a random port is automatically chosen.
2929 If you just want a simple readonly console you can use @code{netcat} or
2930 @code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
2931 @code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
2932 will appear in the netconsole session.
2934 If you plan to send characters back via netconsole or you want to stop
2935 and start QEMU a lot of times, you should have QEMU use the same
2936 source port each time by using something like @code{-serial
2937 udp::4555@@:4556} to QEMU. Another approach is to use a patched
2938 version of netcat which can listen to a TCP port and send and receive
2939 characters via udp. If you have a patched version of netcat which
2940 activates telnet remote echo and single char transfer, then you can
2941 use the following options to step up a netcat redirector to allow
2942 telnet on port 5555 to access the QEMU port.
2943 @table @code
2944 @item QEMU Options:
2945 -serial udp::4555@@:4556
2946 @item netcat options:
2947 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
2948 @item telnet options:
2949 localhost 5555
2950 @end table
2952 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}]
2953 The TCP Net Console has two modes of operation. It can send the serial
2954 I/O to a location or wait for a connection from a location. By default
2955 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
2956 the @var{server} option QEMU will wait for a client socket application
2957 to connect to the port before continuing, unless the @code{nowait}
2958 option was specified. The @code{nodelay} option disables the Nagle buffering
2959 algorithm. The @code{reconnect} option only applies if @var{noserver} is
2960 set, if the connection goes down it will attempt to reconnect at the
2961 given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only
2962 one TCP connection at a time is accepted. You can use @code{telnet} to
2963 connect to the corresponding character device.
2964 @table @code
2965 @item Example to send tcp console to 192.168.0.2 port 4444
2966 -serial tcp:192.168.0.2:4444
2967 @item Example to listen and wait on port 4444 for connection
2968 -serial tcp::4444,server
2969 @item Example to not wait and listen on ip 192.168.0.100 port 4444
2970 -serial tcp:192.168.0.100:4444,server,nowait
2971 @end table
2973 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
2974 The telnet protocol is used instead of raw tcp sockets. The options
2975 work the same as if you had specified @code{-serial tcp}. The
2976 difference is that the port acts like a telnet server or client using
2977 telnet option negotiation. This will also allow you to send the
2978 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
2979 sequence. Typically in unix telnet you do it with Control-] and then
2980 type "send break" followed by pressing the enter key.
2982 @item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}]
2983 A unix domain socket is used instead of a tcp socket. The option works the
2984 same as if you had specified @code{-serial tcp} except the unix domain socket
2985 @var{path} is used for connections.
2987 @item mon:@var{dev_string}
2988 This is a special option to allow the monitor to be multiplexed onto
2989 another serial port. The monitor is accessed with key sequence of
2990 @key{Control-a} and then pressing @key{c}.
2991 @var{dev_string} should be any one of the serial devices specified
2992 above. An example to multiplex the monitor onto a telnet server
2993 listening on port 4444 would be:
2994 @table @code
2995 @item -serial mon:telnet::4444,server,nowait
2996 @end table
2997 When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
2998 QEMU any more but will be passed to the guest instead.
3000 @item braille
3001 Braille device. This will use BrlAPI to display the braille output on a real
3002 or fake device.
3004 @item msmouse
3005 Three button serial mouse. Configure the guest to use Microsoft protocol.
3006 @end table
3007 ETEXI
3009 DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
3010 "-parallel dev redirect the parallel port to char device 'dev'\n",
3011 QEMU_ARCH_ALL)
3012 STEXI
3013 @item -parallel @var{dev}
3014 @findex -parallel
3015 Redirect the virtual parallel port to host device @var{dev} (same
3016 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
3017 be used to use hardware devices connected on the corresponding host
3018 parallel port.
3020 This option can be used several times to simulate up to 3 parallel
3021 ports.
3023 Use @code{-parallel none} to disable all parallel ports.
3024 ETEXI
3026 DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
3027 "-monitor dev redirect the monitor to char device 'dev'\n",
3028 QEMU_ARCH_ALL)
3029 STEXI
3030 @item -monitor @var{dev}
3031 @findex -monitor
3032 Redirect the monitor to host device @var{dev} (same devices as the
3033 serial port).
3034 The default device is @code{vc} in graphical mode and @code{stdio} in
3035 non graphical mode.
3036 Use @code{-monitor none} to disable the default monitor.
3037 ETEXI
3038 DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
3039 "-qmp dev like -monitor but opens in 'control' mode\n",
3040 QEMU_ARCH_ALL)
3041 STEXI
3042 @item -qmp @var{dev}
3043 @findex -qmp
3044 Like -monitor but opens in 'control' mode.
3045 ETEXI
3046 DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \
3047 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n",
3048 QEMU_ARCH_ALL)
3049 STEXI
3050 @item -qmp-pretty @var{dev}
3051 @findex -qmp-pretty
3052 Like -qmp but uses pretty JSON formatting.
3053 ETEXI
3055 DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
3056 "-mon [chardev=]name[,mode=readline|control][,default]\n", QEMU_ARCH_ALL)
3057 STEXI
3058 @item -mon [chardev=]name[,mode=readline|control][,default]
3059 @findex -mon
3060 Setup monitor on chardev @var{name}.
3061 ETEXI
3063 DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
3064 "-debugcon dev redirect the debug console to char device 'dev'\n",
3065 QEMU_ARCH_ALL)
3066 STEXI
3067 @item -debugcon @var{dev}
3068 @findex -debugcon
3069 Redirect the debug console to host device @var{dev} (same devices as the
3070 serial port). The debug console is an I/O port which is typically port
3071 0xe9; writing to that I/O port sends output to this device.
3072 The default device is @code{vc} in graphical mode and @code{stdio} in
3073 non graphical mode.
3074 ETEXI
3076 DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
3077 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL)
3078 STEXI
3079 @item -pidfile @var{file}
3080 @findex -pidfile
3081 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
3082 from a script.
3083 ETEXI
3085 DEF("singlestep", 0, QEMU_OPTION_singlestep, \
3086 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL)
3087 STEXI
3088 @item -singlestep
3089 @findex -singlestep
3090 Run the emulation in single step mode.
3091 ETEXI
3093 DEF("S", 0, QEMU_OPTION_S, \
3094 "-S freeze CPU at startup (use 'c' to start execution)\n",
3095 QEMU_ARCH_ALL)
3096 STEXI
3097 @item -S
3098 @findex -S
3099 Do not start CPU at startup (you must type 'c' in the monitor).
3100 ETEXI
3102 DEF("realtime", HAS_ARG, QEMU_OPTION_realtime,
3103 "-realtime [mlock=on|off]\n"
3104 " run qemu with realtime features\n"
3105 " mlock=on|off controls mlock support (default: on)\n",
3106 QEMU_ARCH_ALL)
3107 STEXI
3108 @item -realtime mlock=on|off
3109 @findex -realtime
3110 Run qemu with realtime features.
3111 mlocking qemu and guest memory can be enabled via @option{mlock=on}
3112 (enabled by default).
3113 ETEXI
3115 DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
3116 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL)
3117 STEXI
3118 @item -gdb @var{dev}
3119 @findex -gdb
3120 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
3121 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
3122 stdio are reasonable use case. The latter is allowing to start QEMU from
3123 within gdb and establish the connection via a pipe:
3124 @example
3125 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
3126 @end example
3127 ETEXI
3129 DEF("s", 0, QEMU_OPTION_s, \
3130 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
3131 QEMU_ARCH_ALL)
3132 STEXI
3133 @item -s
3134 @findex -s
3135 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
3136 (@pxref{gdb_usage}).
3137 ETEXI
3139 DEF("d", HAS_ARG, QEMU_OPTION_d, \
3140 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n",
3141 QEMU_ARCH_ALL)
3142 STEXI
3143 @item -d @var{item1}[,...]
3144 @findex -d
3145 Enable logging of specified items. Use '-d help' for a list of log items.
3146 ETEXI
3148 DEF("D", HAS_ARG, QEMU_OPTION_D, \
3149 "-D logfile output log to logfile (default stderr)\n",
3150 QEMU_ARCH_ALL)
3151 STEXI
3152 @item -D @var{logfile}
3153 @findex -D
3154 Output log in @var{logfile} instead of to stderr
3155 ETEXI
3157 DEF("L", HAS_ARG, QEMU_OPTION_L, \
3158 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
3159 QEMU_ARCH_ALL)
3160 STEXI
3161 @item -L @var{path}
3162 @findex -L
3163 Set the directory for the BIOS, VGA BIOS and keymaps.
3164 ETEXI
3166 DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
3167 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL)
3168 STEXI
3169 @item -bios @var{file}
3170 @findex -bios
3171 Set the filename for the BIOS.
3172 ETEXI
3174 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
3175 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL)
3176 STEXI
3177 @item -enable-kvm
3178 @findex -enable-kvm
3179 Enable KVM full virtualization support. This option is only available
3180 if KVM support is enabled when compiling.
3181 ETEXI
3183 DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
3184 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL)
3185 DEF("xen-create", 0, QEMU_OPTION_xen_create,
3186 "-xen-create create domain using xen hypercalls, bypassing xend\n"
3187 " warning: should not be used when xend is in use\n",
3188 QEMU_ARCH_ALL)
3189 DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
3190 "-xen-attach attach to existing xen domain\n"
3191 " xend will use this when starting QEMU\n",
3192 QEMU_ARCH_ALL)
3193 STEXI
3194 @item -xen-domid @var{id}
3195 @findex -xen-domid
3196 Specify xen guest domain @var{id} (XEN only).
3197 @item -xen-create
3198 @findex -xen-create
3199 Create domain using xen hypercalls, bypassing xend.
3200 Warning: should not be used when xend is in use (XEN only).
3201 @item -xen-attach
3202 @findex -xen-attach
3203 Attach to existing xen domain.
3204 xend will use this when starting QEMU (XEN only).
3205 ETEXI
3207 DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
3208 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL)
3209 STEXI
3210 @item -no-reboot
3211 @findex -no-reboot
3212 Exit instead of rebooting.
3213 ETEXI
3215 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
3216 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL)
3217 STEXI
3218 @item -no-shutdown
3219 @findex -no-shutdown
3220 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
3221 This allows for instance switching to monitor to commit changes to the
3222 disk image.
3223 ETEXI
3225 DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
3226 "-loadvm [tag|id]\n" \
3227 " start right away with a saved state (loadvm in monitor)\n",
3228 QEMU_ARCH_ALL)
3229 STEXI
3230 @item -loadvm @var{file}
3231 @findex -loadvm
3232 Start right away with a saved state (@code{loadvm} in monitor)
3233 ETEXI
3235 #ifndef _WIN32
3236 DEF("daemonize", 0, QEMU_OPTION_daemonize, \
3237 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
3238 #endif
3239 STEXI
3240 @item -daemonize
3241 @findex -daemonize
3242 Daemonize the QEMU process after initialization. QEMU will not detach from
3243 standard IO until it is ready to receive connections on any of its devices.
3244 This option is a useful way for external programs to launch QEMU without having
3245 to cope with initialization race conditions.
3246 ETEXI
3248 DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
3249 "-option-rom rom load a file, rom, into the option ROM space\n",
3250 QEMU_ARCH_ALL)
3251 STEXI
3252 @item -option-rom @var{file}
3253 @findex -option-rom
3254 Load the contents of @var{file} as an option ROM.
3255 This option is useful to load things like EtherBoot.
3256 ETEXI
3258 HXCOMM Silently ignored for compatibility
3259 DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL)
3261 HXCOMM Options deprecated by -rtc
3262 DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
3263 DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
3265 DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
3266 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
3267 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
3268 QEMU_ARCH_ALL)
3270 STEXI
3272 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
3273 @findex -rtc
3274 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
3275 UTC or local time, respectively. @code{localtime} is required for correct date in
3276 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
3277 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
3279 By default the RTC is driven by the host system time. This allows using of the
3280 RTC as accurate reference clock inside the guest, specifically if the host
3281 time is smoothly following an accurate external reference clock, e.g. via NTP.
3282 If you want to isolate the guest time from the host, you can set @option{clock}
3283 to @code{rt} instead. To even prevent it from progressing during suspension,
3284 you can set it to @code{vm}.
3286 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
3287 specifically with Windows' ACPI HAL. This option will try to figure out how
3288 many timer interrupts were not processed by the Windows guest and will
3289 re-inject them.
3290 ETEXI
3292 DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
3293 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>]\n" \
3294 " enable virtual instruction counter with 2^N clock ticks per\n" \
3295 " instruction, enable aligning the host and virtual clocks\n" \
3296 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL)
3297 STEXI
3298 @item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename}]
3299 @findex -icount
3300 Enable virtual instruction counter. The virtual cpu will execute one
3301 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
3302 then the virtual cpu speed will be automatically adjusted to keep virtual
3303 time within a few seconds of real time.
3305 When the virtual cpu is sleeping, the virtual time will advance at default
3306 speed unless @option{sleep=on|off} is specified.
3307 With @option{sleep=on|off}, the virtual time will jump to the next timer deadline
3308 instantly whenever the virtual cpu goes to sleep mode and will not advance
3309 if no timer is enabled. This behavior give deterministic execution times from
3310 the guest point of view.
3312 Note that while this option can give deterministic behavior, it does not
3313 provide cycle accurate emulation. Modern CPUs contain superscalar out of
3314 order cores with complex cache hierarchies. The number of instructions
3315 executed often has little or no correlation with actual performance.
3317 @option{align=on} will activate the delay algorithm which will try
3318 to synchronise the host clock and the virtual clock. The goal is to
3319 have a guest running at the real frequency imposed by the shift option.
3320 Whenever the guest clock is behind the host clock and if
3321 @option{align=on} is specified then we print a message to the user
3322 to inform about the delay.
3323 Currently this option does not work when @option{shift} is @code{auto}.
3324 Note: The sync algorithm will work for those shift values for which
3325 the guest clock runs ahead of the host clock. Typically this happens
3326 when the shift value is high (how high depends on the host machine).
3328 When @option{rr} option is specified deterministic record/replay is enabled.
3329 Replay log is written into @var{filename} file in record mode and
3330 read from this file in replay mode.
3331 ETEXI
3333 DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
3334 "-watchdog model\n" \
3335 " enable virtual hardware watchdog [default=none]\n",
3336 QEMU_ARCH_ALL)
3337 STEXI
3338 @item -watchdog @var{model}
3339 @findex -watchdog
3340 Create a virtual hardware watchdog device. Once enabled (by a guest
3341 action), the watchdog must be periodically polled by an agent inside
3342 the guest or else the guest will be restarted. Choose a model for
3343 which your guest has drivers.
3345 The @var{model} is the model of hardware watchdog to emulate. Use
3346 @code{-watchdog help} to list available hardware models. Only one
3347 watchdog can be enabled for a guest.
3349 The following models may be available:
3350 @table @option
3351 @item ib700
3352 iBASE 700 is a very simple ISA watchdog with a single timer.
3353 @item i6300esb
3354 Intel 6300ESB I/O controller hub is a much more featureful PCI-based
3355 dual-timer watchdog.
3356 @item diag288
3357 A virtual watchdog for s390x backed by the diagnose 288 hypercall
3358 (currently KVM only).
3359 @end table
3360 ETEXI
3362 DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
3363 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
3364 " action when watchdog fires [default=reset]\n",
3365 QEMU_ARCH_ALL)
3366 STEXI
3367 @item -watchdog-action @var{action}
3368 @findex -watchdog-action
3370 The @var{action} controls what QEMU will do when the watchdog timer
3371 expires.
3372 The default is
3373 @code{reset} (forcefully reset the guest).
3374 Other possible actions are:
3375 @code{shutdown} (attempt to gracefully shutdown the guest),
3376 @code{poweroff} (forcefully poweroff the guest),
3377 @code{pause} (pause the guest),
3378 @code{debug} (print a debug message and continue), or
3379 @code{none} (do nothing).
3381 Note that the @code{shutdown} action requires that the guest responds
3382 to ACPI signals, which it may not be able to do in the sort of
3383 situations where the watchdog would have expired, and thus
3384 @code{-watchdog-action shutdown} is not recommended for production use.
3386 Examples:
3388 @table @code
3389 @item -watchdog i6300esb -watchdog-action pause
3390 @itemx -watchdog ib700
3391 @end table
3392 ETEXI
3394 DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
3395 "-echr chr set terminal escape character instead of ctrl-a\n",
3396 QEMU_ARCH_ALL)
3397 STEXI
3399 @item -echr @var{numeric_ascii_value}
3400 @findex -echr
3401 Change the escape character used for switching to the monitor when using
3402 monitor and serial sharing. The default is @code{0x01} when using the
3403 @code{-nographic} option. @code{0x01} is equal to pressing
3404 @code{Control-a}. You can select a different character from the ascii
3405 control keys where 1 through 26 map to Control-a through Control-z. For
3406 instance you could use the either of the following to change the escape
3407 character to Control-t.
3408 @table @code
3409 @item -echr 0x14
3410 @itemx -echr 20
3411 @end table
3412 ETEXI
3414 DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
3415 "-virtioconsole c\n" \
3416 " set virtio console\n", QEMU_ARCH_ALL)
3417 STEXI
3418 @item -virtioconsole @var{c}
3419 @findex -virtioconsole
3420 Set virtio console.
3422 This option is maintained for backward compatibility.
3424 Please use @code{-device virtconsole} for the new way of invocation.
3425 ETEXI
3427 DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
3428 "-show-cursor show cursor\n", QEMU_ARCH_ALL)
3429 STEXI
3430 @item -show-cursor
3431 @findex -show-cursor
3432 Show cursor.
3433 ETEXI
3435 DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
3436 "-tb-size n set TB size\n", QEMU_ARCH_ALL)
3437 STEXI
3438 @item -tb-size @var{n}
3439 @findex -tb-size
3440 Set TB size.
3441 ETEXI
3443 DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
3444 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \
3445 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \
3446 "-incoming unix:socketpath\n" \
3447 " prepare for incoming migration, listen on\n" \
3448 " specified protocol and socket address\n" \
3449 "-incoming fd:fd\n" \
3450 "-incoming exec:cmdline\n" \
3451 " accept incoming migration on given file descriptor\n" \
3452 " or from given external command\n" \
3453 "-incoming defer\n" \
3454 " wait for the URI to be specified via migrate_incoming\n",
3455 QEMU_ARCH_ALL)
3456 STEXI
3457 @item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6]
3458 @itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6]
3459 @findex -incoming
3460 Prepare for incoming migration, listen on a given tcp port.
3462 @item -incoming unix:@var{socketpath}
3463 Prepare for incoming migration, listen on a given unix socket.
3465 @item -incoming fd:@var{fd}
3466 Accept incoming migration from a given filedescriptor.
3468 @item -incoming exec:@var{cmdline}
3469 Accept incoming migration as an output from specified external command.
3471 @item -incoming defer
3472 Wait for the URI to be specified via migrate_incoming. The monitor can
3473 be used to change settings (such as migration parameters) prior to issuing
3474 the migrate_incoming to allow the migration to begin.
3475 ETEXI
3477 DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
3478 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL)
3479 STEXI
3480 @item -nodefaults
3481 @findex -nodefaults
3482 Don't create default devices. Normally, QEMU sets the default devices like serial
3483 port, parallel port, virtual console, monitor device, VGA adapter, floppy and
3484 CD-ROM drive and others. The @code{-nodefaults} option will disable all those
3485 default devices.
3486 ETEXI
3488 #ifndef _WIN32
3489 DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
3490 "-chroot dir chroot to dir just before starting the VM\n",
3491 QEMU_ARCH_ALL)
3492 #endif
3493 STEXI
3494 @item -chroot @var{dir}
3495 @findex -chroot
3496 Immediately before starting guest execution, chroot to the specified
3497 directory. Especially useful in combination with -runas.
3498 ETEXI
3500 #ifndef _WIN32
3501 DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
3502 "-runas user change to user id user just before starting the VM\n",
3503 QEMU_ARCH_ALL)
3504 #endif
3505 STEXI
3506 @item -runas @var{user}
3507 @findex -runas
3508 Immediately before starting guest execution, drop root privileges, switching
3509 to the specified user.
3510 ETEXI
3512 DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
3513 "-prom-env variable=value\n"
3514 " set OpenBIOS nvram variables\n",
3515 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3516 STEXI
3517 @item -prom-env @var{variable}=@var{value}
3518 @findex -prom-env
3519 Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
3520 ETEXI
3521 DEF("semihosting", 0, QEMU_OPTION_semihosting,
3522 "-semihosting semihosting mode\n",
3523 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3524 QEMU_ARCH_MIPS)
3525 STEXI
3526 @item -semihosting
3527 @findex -semihosting
3528 Enable semihosting mode (ARM, M68K, Xtensa, MIPS only).
3529 ETEXI
3530 DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config,
3531 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \
3532 " semihosting configuration\n",
3533 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3534 QEMU_ARCH_MIPS)
3535 STEXI
3536 @item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]
3537 @findex -semihosting-config
3538 Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only).
3539 @table @option
3540 @item target=@code{native|gdb|auto}
3541 Defines where the semihosting calls will be addressed, to QEMU (@code{native})
3542 or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb}
3543 during debug sessions and @code{native} otherwise.
3544 @item arg=@var{str1},arg=@var{str2},...
3545 Allows the user to pass input arguments, and can be used multiple times to build
3546 up a list. The old-style @code{-kernel}/@code{-append} method of passing a
3547 command line is still supported for backward compatibility. If both the
3548 @code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are
3549 specified, the former is passed to semihosting as it always takes precedence.
3550 @end table
3551 ETEXI
3552 DEF("old-param", 0, QEMU_OPTION_old_param,
3553 "-old-param old param mode\n", QEMU_ARCH_ARM)
3554 STEXI
3555 @item -old-param
3556 @findex -old-param (ARM)
3557 Old param mode (ARM only).
3558 ETEXI
3560 DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
3561 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n",
3562 QEMU_ARCH_ALL)
3563 STEXI
3564 @item -sandbox @var{arg}
3565 @findex -sandbox
3566 Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
3567 disable it. The default is 'off'.
3568 ETEXI
3570 DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
3571 "-readconfig <file>\n", QEMU_ARCH_ALL)
3572 STEXI
3573 @item -readconfig @var{file}
3574 @findex -readconfig
3575 Read device configuration from @var{file}. This approach is useful when you want to spawn
3576 QEMU process with many command line options but you don't want to exceed the command line
3577 character limit.
3578 ETEXI
3579 DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
3580 "-writeconfig <file>\n"
3581 " read/write config file\n", QEMU_ARCH_ALL)
3582 STEXI
3583 @item -writeconfig @var{file}
3584 @findex -writeconfig
3585 Write device configuration to @var{file}. The @var{file} can be either filename to save
3586 command line and device configuration into file or dash @code{-}) character to print the
3587 output to stdout. This can be later used as input file for @code{-readconfig} option.
3588 ETEXI
3589 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig,
3590 "-nodefconfig\n"
3591 " do not load default config files at startup\n",
3592 QEMU_ARCH_ALL)
3593 STEXI
3594 @item -nodefconfig
3595 @findex -nodefconfig
3596 Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
3597 The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
3598 ETEXI
3599 DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
3600 "-no-user-config\n"
3601 " do not load user-provided config files at startup\n",
3602 QEMU_ARCH_ALL)
3603 STEXI
3604 @item -no-user-config
3605 @findex -no-user-config
3606 The @code{-no-user-config} option makes QEMU not load any of the user-provided
3607 config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config
3608 files from @var{datadir}.
3609 ETEXI
3610 DEF("trace", HAS_ARG, QEMU_OPTION_trace,
3611 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
3612 " specify tracing options\n",
3613 QEMU_ARCH_ALL)
3614 STEXI
3615 HXCOMM This line is not accurate, as some sub-options are backend-specific but
3616 HXCOMM HX does not support conditional compilation of text.
3617 @item -trace [events=@var{file}][,file=@var{file}]
3618 @findex -trace
3620 Specify tracing options.
3622 @table @option
3623 @item [enable=]@var{pattern}
3624 Immediately enable events matching @var{pattern}.
3625 The file must contain one event name (as listed in the @file{trace-events} file)
3626 per line; globbing patterns are accepted too. This option is only
3627 available if QEMU has been compiled with the @var{simple}, @var{stderr}
3628 or @var{ftrace} tracing backend. To specify multiple events or patterns,
3629 specify the @option{-trace} option multiple times.
3631 Use @code{-trace help} to print a list of names of trace points.
3633 @item events=@var{file}
3634 Immediately enable events listed in @var{file}.
3635 The file must contain one event name (as listed in the @file{trace-events} file)
3636 per line; globbing patterns are accepted too. This option is only
3637 available if QEMU has been compiled with the @var{simple}, @var{stderr} or
3638 @var{ftrace} tracing backend.
3640 @item file=@var{file}
3641 Log output traces to @var{file}.
3642 This option is only available if QEMU has been compiled with
3643 the @var{simple} tracing backend.
3644 @end table
3645 ETEXI
3647 HXCOMM Internal use
3648 DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL)
3649 DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL)
3651 #ifdef __linux__
3652 DEF("enable-fips", 0, QEMU_OPTION_enablefips,
3653 "-enable-fips enable FIPS 140-2 compliance\n",
3654 QEMU_ARCH_ALL)
3655 #endif
3656 STEXI
3657 @item -enable-fips
3658 @findex -enable-fips
3659 Enable FIPS 140-2 compliance mode.
3660 ETEXI
3662 HXCOMM Deprecated by -machine accel=tcg property
3663 DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386)
3665 HXCOMM Deprecated by kvm-pit driver properties
3666 DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection,
3667 "", QEMU_ARCH_I386)
3669 HXCOMM Deprecated (ignored)
3670 DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386)
3672 HXCOMM Deprecated by -machine kernel_irqchip=on|off property
3673 DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386)
3675 HXCOMM Deprecated (ignored)
3676 DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL)
3678 DEF("msg", HAS_ARG, QEMU_OPTION_msg,
3679 "-msg timestamp[=on|off]\n"
3680 " change the format of messages\n"
3681 " on|off controls leading timestamps (default:on)\n",
3682 QEMU_ARCH_ALL)
3683 STEXI
3684 @item -msg timestamp[=on|off]
3685 @findex -msg
3686 prepend a timestamp to each log message.(default:on)
3687 ETEXI
3689 DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate,
3690 "-dump-vmstate <file>\n"
3691 " Output vmstate information in JSON format to file.\n"
3692 " Use the scripts/vmstate-static-checker.py file to\n"
3693 " check for possible regressions in migration code\n"
3694 " by comparing two such vmstate dumps.\n",
3695 QEMU_ARCH_ALL)
3696 STEXI
3697 @item -dump-vmstate @var{file}
3698 @findex -dump-vmstate
3699 Dump json-encoded vmstate information for current machine type to file
3700 in @var{file}
3701 ETEXI
3703 DEFHEADING(Generic object creation)
3705 DEF("object", HAS_ARG, QEMU_OPTION_object,
3706 "-object TYPENAME[,PROP1=VALUE1,...]\n"
3707 " create a new object of type TYPENAME setting properties\n"
3708 " in the order they are specified. Note that the 'id'\n"
3709 " property must be set. These objects are placed in the\n"
3710 " '/objects' path.\n",
3711 QEMU_ARCH_ALL)
3712 STEXI
3713 @item -object @var{typename}[,@var{prop1}=@var{value1},...]
3714 @findex -object
3715 Create a new object of type @var{typename} setting properties
3716 in the order they are specified. Note that the 'id'
3717 property must be set. These objects are placed in the
3718 '/objects' path.
3720 @table @option
3722 @item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off}
3724 Creates a memory file backend object, which can be used to back
3725 the guest RAM with huge pages. The @option{id} parameter is a
3726 unique ID that will be used to reference this memory region
3727 when configuring the @option{-numa} argument. The @option{size}
3728 option provides the size of the memory region, and accepts
3729 common suffixes, eg @option{500M}. The @option{mem-path} provides
3730 the path to either a shared memory or huge page filesystem mount.
3731 The @option{share} boolean option determines whether the memory
3732 region is marked as private to QEMU, or shared. The latter allows
3733 a co-operating external process to access the QEMU memory region.
3735 @item -object rng-random,id=@var{id},filename=@var{/dev/random}
3737 Creates a random number generator backend which obtains entropy from
3738 a device on the host. The @option{id} parameter is a unique ID that
3739 will be used to reference this entropy backend from the @option{virtio-rng}
3740 device. The @option{filename} parameter specifies which file to obtain
3741 entropy from and if omitted defaults to @option{/dev/random}.
3743 @item -object rng-egd,id=@var{id},chardev=@var{chardevid}
3745 Creates a random number generator backend which obtains entropy from
3746 an external daemon running on the host. The @option{id} parameter is
3747 a unique ID that will be used to reference this entropy backend from
3748 the @option{virtio-rng} device. The @option{chardev} parameter is
3749 the unique ID of a character device backend that provides the connection
3750 to the RNG daemon.
3752 @item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off}
3754 Creates a TLS anonymous credentials object, which can be used to provide
3755 TLS support on network backends. The @option{id} parameter is a unique
3756 ID which network backends will use to access the credentials. The
3757 @option{endpoint} is either @option{server} or @option{client} depending
3758 on whether the QEMU network backend that uses the credentials will be
3759 acting as a client or as a server. If @option{verify-peer} is enabled
3760 (the default) then once the handshake is completed, the peer credentials
3761 will be verified, though this is a no-op for anonymous credentials.
3763 The @var{dir} parameter tells QEMU where to find the credential
3764 files. For server endpoints, this directory may contain a file
3765 @var{dh-params.pem} providing diffie-hellman parameters to use
3766 for the TLS server. If the file is missing, QEMU will generate
3767 a set of DH parameters at startup. This is a computationally
3768 expensive operation that consumes random pool entropy, so it is
3769 recommended that a persistent set of parameters be generated
3770 upfront and saved.
3772 @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}
3774 Creates a TLS anonymous credentials object, which can be used to provide
3775 TLS support on network backends. The @option{id} parameter is a unique
3776 ID which network backends will use to access the credentials. The
3777 @option{endpoint} is either @option{server} or @option{client} depending
3778 on whether the QEMU network backend that uses the credentials will be
3779 acting as a client or as a server. If @option{verify-peer} is enabled
3780 (the default) then once the handshake is completed, the peer credentials
3781 will be verified. With x509 certificates, this implies that the clients
3782 must be provided with valid client certificates too.
3784 The @var{dir} parameter tells QEMU where to find the credential
3785 files. For server endpoints, this directory may contain a file
3786 @var{dh-params.pem} providing diffie-hellman parameters to use
3787 for the TLS server. If the file is missing, QEMU will generate
3788 a set of DH parameters at startup. This is a computationally
3789 expensive operation that consumes random pool entropy, so it is
3790 recommended that a persistent set of parameters be generated
3791 upfront and saved.
3793 For x509 certificate credentials the directory will contain further files
3794 providing the x509 certificates. The certificates must be stored
3795 in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional),
3796 @var{server-cert.pem} (only servers), @var{server-key.pem} (only servers),
3797 @var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients).
3799 For the @var{server-key.pem} and @var{client-key.pem} files which
3800 contain sensitive private keys, it is possible to use an encrypted
3801 version by providing the @var{passwordid} parameter. This provides
3802 the ID of a previously created @code{secret} object containing the
3803 password for decryption.
3805 @item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}]
3807 Interval @var{t} can't be 0, this filter batches the packet delivery: all
3808 packets arriving in a given interval on netdev @var{netdevid} are delayed
3809 until the end of the interval. Interval is in microseconds.
3810 @option{status} is optional that indicate whether the netfilter is
3811 on (enabled) or off (disabled), the default status for netfilter will be 'on'.
3813 queue @var{all|rx|tx} is an option that can be applied to any netfilter.
3815 @option{all}: the filter is attached both to the receive and the transmit
3816 queue of the netdev (default).
3818 @option{rx}: the filter is attached to the receive queue of the netdev,
3819 where it will receive packets sent to the netdev.
3821 @option{tx}: the filter is attached to the transmit queue of the netdev,
3822 where it will receive packets sent by the netdev.
3824 @item -object filter-dump,id=@var{id},netdev=@var{dev},file=@var{filename}][,maxlen=@var{len}]
3826 Dump the network traffic on netdev @var{dev} to the file specified by
3827 @var{filename}. At most @var{len} bytes (64k by default) per packet are stored.
3828 The file format is libpcap, so it can be analyzed with tools such as tcpdump
3829 or Wireshark.
3831 @item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
3832 @item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
3834 Defines a secret to store a password, encryption key, or some other sensitive
3835 data. The sensitive data can either be passed directly via the @var{data}
3836 parameter, or indirectly via the @var{file} parameter. Using the @var{data}
3837 parameter is insecure unless the sensitive data is encrypted.
3839 The sensitive data can be provided in raw format (the default), or base64.
3840 When encoded as JSON, the raw format only supports valid UTF-8 characters,
3841 so base64 is recommended for sending binary data. QEMU will convert from
3842 which ever format is provided to the format it needs internally. eg, an
3843 RBD password can be provided in raw format, even though it will be base64
3844 encoded when passed onto the RBD sever.
3846 For added protection, it is possible to encrypt the data associated with
3847 a secret using the AES-256-CBC cipher. Use of encryption is indicated
3848 by providing the @var{keyid} and @var{iv} parameters. The @var{keyid}
3849 parameter provides the ID of a previously defined secret that contains
3850 the AES-256 decryption key. This key should be 32-bytes long and be
3851 base64 encoded. The @var{iv} parameter provides the random initialization
3852 vector used for encryption of this particular secret and should be a
3853 base64 encrypted string of the 32-byte IV.
3855 The simplest (insecure) usage is to provide the secret inline
3857 @example
3859 # $QEMU -object secret,id=sec0,data=letmein,format=raw
3861 @end example
3863 The simplest secure usage is to provide the secret via a file
3865 # echo -n "letmein" > mypasswd.txt
3866 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw
3868 For greater security, AES-256-CBC should be used. To illustrate usage,
3869 consider the openssl command line tool which can encrypt the data. Note
3870 that when encrypting, the plaintext must be padded to the cipher block
3871 size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm.
3873 First a master key needs to be created in base64 encoding:
3875 @example
3876 # openssl rand -base64 32 > key.b64
3877 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"')
3878 @end example
3880 Each secret to be encrypted needs to have a random initialization vector
3881 generated. These do not need to be kept secret
3883 @example
3884 # openssl rand -base64 16 > iv.b64
3885 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"')
3886 @end example
3888 The secret to be defined can now be encrypted, in this case we're
3889 telling openssl to base64 encode the result, but it could be left
3890 as raw bytes if desired.
3892 @example
3893 # SECRET=$(echo -n "letmein" |
3894 openssl enc -aes-256-cbc -a -K $KEY -iv $IV)
3895 @end example
3897 When launching QEMU, create a master secret pointing to @code{key.b64}
3898 and specify that to be used to decrypt the user password. Pass the
3899 contents of @code{iv.b64} to the second secret
3901 @example
3902 # $QEMU \
3903 -object secret,id=secmaster0,format=base64,file=key.b64 \
3904 -object secret,id=sec0,keyid=secmaster0,format=base64,\
3905 data=$SECRET,iv=$(<iv.b64)
3906 @end example
3908 @end table
3910 ETEXI
3913 HXCOMM This is the last statement. Insert new options before this line!
3914 STEXI
3915 @end table
3916 ETEXI