xref: /openbmc/qemu/qemu-options.hx (revision 4d60b25b)
1HXCOMM Use DEFHEADING() to define headings in both help text and texi
2HXCOMM Text between STEXI and ETEXI are copied to texi version and
3HXCOMM discarded from C version
4HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to
5HXCOMM construct option structures, enums and help message for specified
6HXCOMM architectures.
7HXCOMM HXCOMM can be used for comments, discarded from both texi and C
8
9DEFHEADING(Standard options)
10STEXI
11@table @option
12ETEXI
13
14DEF("help", 0, QEMU_OPTION_h,
15    "-h or -help     display this help and exit\n", QEMU_ARCH_ALL)
16STEXI
17@item -h
18@findex -h
19Display help and exit
20ETEXI
21
22DEF("version", 0, QEMU_OPTION_version,
23    "-version        display version information and exit\n", QEMU_ARCH_ALL)
24STEXI
25@item -version
26@findex -version
27Display version information and exit
28ETEXI
29
30DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
31    "-machine [type=]name[,prop[=value][,...]]\n"
32    "                selects emulated machine ('-machine help' for list)\n"
33    "                property accel=accel1[:accel2[:...]] selects accelerator\n"
34    "                supported accelerators are kvm, xen, hax or tcg (default: tcg)\n"
35    "                kernel_irqchip=on|off|split controls accelerated irqchip support (default=off)\n"
36    "                vmport=on|off|auto controls emulation of vmport (default: auto)\n"
37    "                kvm_shadow_mem=size of KVM shadow MMU in bytes\n"
38    "                dump-guest-core=on|off include guest memory in a core dump (default=on)\n"
39    "                mem-merge=on|off controls memory merge support (default: on)\n"
40    "                igd-passthru=on|off controls IGD GFX passthrough support (default=off)\n"
41    "                aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n"
42    "                dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n"
43    "                suppress-vmdesc=on|off disables self-describing migration (default=off)\n"
44    "                nvdimm=on|off controls NVDIMM support (default=off)\n"
45    "                enforce-config-section=on|off enforce configuration section migration (default=off)\n"
46    "                s390-squash-mcss=on|off (deprecated) controls support for squashing into default css (default=off)\n",
47    QEMU_ARCH_ALL)
48STEXI
49@item -machine [type=]@var{name}[,prop=@var{value}[,...]]
50@findex -machine
51Select the emulated machine by @var{name}. Use @code{-machine help} to list
52available machines.
53
54For architectures which aim to support live migration compatibility
55across releases, each release will introduce a new versioned machine
56type. For example, the 2.8.0 release introduced machine types
57``pc-i440fx-2.8'' and ``pc-q35-2.8'' for the x86_64/i686 architectures.
58
59To allow live migration of guests from QEMU version 2.8.0, to QEMU
60version 2.9.0, the 2.9.0 version must support the ``pc-i440fx-2.8''
61and ``pc-q35-2.8'' machines too. To allow users live migrating VMs
62to skip multiple intermediate releases when upgrading, new releases
63of QEMU will support machine types from many previous versions.
64
65Supported machine properties are:
66@table @option
67@item accel=@var{accels1}[:@var{accels2}[:...]]
68This is used to enable an accelerator. Depending on the target architecture,
69kvm, xen, hax or tcg can be available. By default, tcg is used. If there is
70more than one accelerator specified, the next one is used if the previous one
71fails to initialize.
72@item kernel_irqchip=on|off
73Controls in-kernel irqchip support for the chosen accelerator when available.
74@item gfx_passthru=on|off
75Enables IGD GFX passthrough support for the chosen machine when available.
76@item vmport=on|off|auto
77Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the
78value based on accel. For accel=xen the default is off otherwise the default
79is on.
80@item kvm_shadow_mem=size
81Defines the size of the KVM shadow MMU.
82@item dump-guest-core=on|off
83Include guest memory in a core dump. The default is on.
84@item mem-merge=on|off
85Enables or disables memory merge support. This feature, when supported by
86the host, de-duplicates identical memory pages among VMs instances
87(enabled by default).
88@item aes-key-wrap=on|off
89Enables or disables AES key wrapping support on s390-ccw hosts. This feature
90controls whether AES wrapping keys will be created to allow
91execution of AES cryptographic functions.  The default is on.
92@item dea-key-wrap=on|off
93Enables or disables DEA key wrapping support on s390-ccw hosts. This feature
94controls whether DEA wrapping keys will be created to allow
95execution of DEA cryptographic functions.  The default is on.
96@item nvdimm=on|off
97Enables or disables NVDIMM support. The default is off.
98@item s390-squash-mcss=on|off
99Enables or disables squashing subchannels into the default css.
100The default is off.
101NOTE: This property is deprecated and will be removed in future releases.
102The ``s390-squash-mcss=on`` property has been obsoleted by allowing the
103cssid to be chosen freely. Instead of squashing subchannels into the
104default channel subsystem image for guests that do not support multiple
105channel subsystems, all devices can be put into the default channel
106subsystem image.
107@item enforce-config-section=on|off
108If @option{enforce-config-section} is set to @var{on}, force migration
109code to send configuration section even if the machine-type sets the
110@option{migration.send-configuration} property to @var{off}.
111NOTE: this parameter is deprecated. Please use @option{-global}
112@option{migration.send-configuration}=@var{on|off} instead.
113@end table
114ETEXI
115
116HXCOMM Deprecated by -machine
117DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL)
118
119DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
120    "-cpu cpu        select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL)
121STEXI
122@item -cpu @var{model}
123@findex -cpu
124Select CPU model (@code{-cpu help} for list and additional feature selection)
125ETEXI
126
127DEF("accel", HAS_ARG, QEMU_OPTION_accel,
128    "-accel [accel=]accelerator[,thread=single|multi]\n"
129    "                select accelerator (kvm, xen, hax or tcg; use 'help' for a list)\n"
130    "                thread=single|multi (enable multi-threaded TCG)\n", QEMU_ARCH_ALL)
131STEXI
132@item -accel @var{name}[,prop=@var{value}[,...]]
133@findex -accel
134This is used to enable an accelerator. Depending on the target architecture,
135kvm, xen, hax or tcg can be available. By default, tcg is used. If there is
136more than one accelerator specified, the next one is used if the previous one
137fails to initialize.
138@table @option
139@item thread=single|multi
140Controls number of TCG threads. When the TCG is multi-threaded there will be one
141thread per vCPU therefor taking advantage of additional host cores. The default
142is to enable multi-threading where both the back-end and front-ends support it and
143no incompatible TCG features have been enabled (e.g. icount/replay).
144@end table
145ETEXI
146
147DEF("smp", HAS_ARG, QEMU_OPTION_smp,
148    "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
149    "                set the number of CPUs to 'n' [default=1]\n"
150    "                maxcpus= maximum number of total cpus, including\n"
151    "                offline CPUs for hotplug, etc\n"
152    "                cores= number of CPU cores on one socket\n"
153    "                threads= number of threads on one CPU core\n"
154    "                sockets= number of discrete sockets in the system\n",
155        QEMU_ARCH_ALL)
156STEXI
157@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
158@findex -smp
159Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
160CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
161to 4.
162For the PC target, the number of @var{cores} per socket, the number
163of @var{threads} per cores and the total number of @var{sockets} can be
164specified. Missing values will be computed. If any on the three values is
165given, the total number of CPUs @var{n} can be omitted. @var{maxcpus}
166specifies the maximum number of hotpluggable CPUs.
167ETEXI
168
169DEF("numa", HAS_ARG, QEMU_OPTION_numa,
170    "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
171    "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n"
172    "-numa dist,src=source,dst=destination,val=distance\n", QEMU_ARCH_ALL)
173STEXI
174@item -numa node[,mem=@var{size}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}]
175@itemx -numa node[,memdev=@var{id}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}]
176@itemx -numa dist,src=@var{source},dst=@var{destination},val=@var{distance}
177@itemx -numa cpu,node-id=@var{node}[,socket-id=@var{x}][,core-id=@var{y}][,thread-id=@var{z}]
178@findex -numa
179Define a NUMA node and assign RAM and VCPUs to it.
180Set the NUMA distance from a source node to a destination node.
181
182Legacy VCPU assignment uses @samp{cpus} option where
183@var{firstcpu} and @var{lastcpu} are CPU indexes. Each
184@samp{cpus} option represent a contiguous range of CPU indexes
185(or a single VCPU if @var{lastcpu} is omitted). A non-contiguous
186set of VCPUs can be represented by providing multiple @samp{cpus}
187options. If @samp{cpus} is omitted on all nodes, VCPUs are automatically
188split between them.
189
190For example, the following option assigns VCPUs 0, 1, 2 and 5 to
191a NUMA node:
192@example
193-numa node,cpus=0-2,cpus=5
194@end example
195
196@samp{cpu} option is a new alternative to @samp{cpus} option
197which uses @samp{socket-id|core-id|thread-id} properties to assign
198CPU objects to a @var{node} using topology layout properties of CPU.
199The set of properties is machine specific, and depends on used
200machine type/@samp{smp} options. It could be queried with
201@samp{hotpluggable-cpus} monitor command.
202@samp{node-id} property specifies @var{node} to which CPU object
203will be assigned, it's required for @var{node} to be declared
204with @samp{node} option before it's used with @samp{cpu} option.
205
206For example:
207@example
208-M pc \
209-smp 1,sockets=2,maxcpus=2 \
210-numa node,nodeid=0 -numa node,nodeid=1 \
211-numa cpu,node-id=0,socket-id=0 -numa cpu,node-id=1,socket-id=1
212@end example
213
214@samp{mem} assigns a given RAM amount to a node. @samp{memdev}
215assigns RAM from a given memory backend device to a node. If
216@samp{mem} and @samp{memdev} are omitted in all nodes, RAM is
217split equally between them.
218
219@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore,
220if one node uses @samp{memdev}, all of them have to use it.
221
222@var{source} and @var{destination} are NUMA node IDs.
223@var{distance} is the NUMA distance from @var{source} to @var{destination}.
224The distance from a node to itself is always 10. If any pair of nodes is
225given a distance, then all pairs must be given distances. Although, when
226distances are only given in one direction for each pair of nodes, then
227the distances in the opposite directions are assumed to be the same. If,
228however, an asymmetrical pair of distances is given for even one node
229pair, then all node pairs must be provided distance values for both
230directions, even when they are symmetrical. When a node is unreachable
231from another node, set the pair's distance to 255.
232
233Note that the -@option{numa} option doesn't allocate any of the
234specified resources, it just assigns existing resources to NUMA
235nodes. This means that one still has to use the @option{-m},
236@option{-smp} options to allocate RAM and VCPUs respectively.
237
238ETEXI
239
240DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
241    "-add-fd fd=fd,set=set[,opaque=opaque]\n"
242    "                Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL)
243STEXI
244@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}]
245@findex -add-fd
246
247Add a file descriptor to an fd set.  Valid options are:
248
249@table @option
250@item fd=@var{fd}
251This option defines the file descriptor of which a duplicate is added to fd set.
252The file descriptor cannot be stdin, stdout, or stderr.
253@item set=@var{set}
254This option defines the ID of the fd set to add the file descriptor to.
255@item opaque=@var{opaque}
256This option defines a free-form string that can be used to describe @var{fd}.
257@end table
258
259You can open an image using pre-opened file descriptors from an fd set:
260@example
261qemu-system-i386
262-add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
263-add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
264-drive file=/dev/fdset/2,index=0,media=disk
265@end example
266ETEXI
267
268DEF("set", HAS_ARG, QEMU_OPTION_set,
269    "-set group.id.arg=value\n"
270    "                set <arg> parameter for item <id> of type <group>\n"
271    "                i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL)
272STEXI
273@item -set @var{group}.@var{id}.@var{arg}=@var{value}
274@findex -set
275Set parameter @var{arg} for item @var{id} of type @var{group}
276ETEXI
277
278DEF("global", HAS_ARG, QEMU_OPTION_global,
279    "-global driver.property=value\n"
280    "-global driver=driver,property=property,value=value\n"
281    "                set a global default for a driver property\n",
282    QEMU_ARCH_ALL)
283STEXI
284@item -global @var{driver}.@var{prop}=@var{value}
285@itemx -global driver=@var{driver},property=@var{property},value=@var{value}
286@findex -global
287Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.:
288
289@example
290qemu-system-i386 -global ide-hd.physical_block_size=4096 disk-image.img
291@end example
292
293In particular, you can use this to set driver properties for devices which are
294created automatically by the machine model. To create a device which is not
295created automatically and set properties on it, use -@option{device}.
296
297-global @var{driver}.@var{prop}=@var{value} is shorthand for -global
298driver=@var{driver},property=@var{prop},value=@var{value}.  The
299longhand syntax works even when @var{driver} contains a dot.
300ETEXI
301
302DEF("boot", HAS_ARG, QEMU_OPTION_boot,
303    "-boot [order=drives][,once=drives][,menu=on|off]\n"
304    "      [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
305    "                'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
306    "                'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n"
307    "                'sp_time': the period that splash picture last if menu=on, unit is ms\n"
308    "                'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n",
309    QEMU_ARCH_ALL)
310STEXI
311@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]
312@findex -boot
313Specify boot order @var{drives} as a string of drive letters. Valid
314drive letters depend on the target architecture. The x86 PC uses: a, b
315(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
316from network adapter 1-4), hard disk boot is the default. To apply a
317particular boot order only on the first startup, specify it via
318@option{once}. Note that the @option{order} or @option{once} parameter
319should not be used together with the @option{bootindex} property of
320devices, since the firmware implementations normally do not support both
321at the same time.
322
323Interactive boot menus/prompts can be enabled via @option{menu=on} as far
324as firmware/BIOS supports them. The default is non-interactive boot.
325
326A splash picture could be passed to bios, enabling user to show it as logo,
327when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
328supports them. Currently Seabios for X86 system support it.
329limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
330format(true color). The resolution should be supported by the SVGA mode, so
331the recommended is 320x240, 640x480, 800x640.
332
333A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms
334when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not
335reboot, qemu passes '-1' to bios by default. Currently Seabios for X86
336system support it.
337
338Do strict boot via @option{strict=on} as far as firmware/BIOS
339supports it. This only effects when boot priority is changed by
340bootindex options. The default is non-strict boot.
341
342@example
343# try to boot from network first, then from hard disk
344qemu-system-i386 -boot order=nc
345# boot from CD-ROM first, switch back to default order after reboot
346qemu-system-i386 -boot once=d
347# boot with a splash picture for 5 seconds.
348qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
349@end example
350
351Note: The legacy format '-boot @var{drives}' is still supported but its
352use is discouraged as it may be removed from future versions.
353ETEXI
354
355DEF("m", HAS_ARG, QEMU_OPTION_m,
356    "-m [size=]megs[,slots=n,maxmem=size]\n"
357    "                configure guest RAM\n"
358    "                size: initial amount of guest memory\n"
359    "                slots: number of hotplug slots (default: none)\n"
360    "                maxmem: maximum amount of guest memory (default: none)\n"
361    "NOTE: Some architectures might enforce a specific granularity\n",
362    QEMU_ARCH_ALL)
363STEXI
364@item -m [size=]@var{megs}[,slots=n,maxmem=size]
365@findex -m
366Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB.
367Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in
368megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem}
369could be used to set amount of hotpluggable memory slots and maximum amount of
370memory. Note that @var{maxmem} must be aligned to the page size.
371
372For example, the following command-line sets the guest startup RAM size to
3731GB, creates 3 slots to hotplug additional memory and sets the maximum
374memory the guest can reach to 4GB:
375
376@example
377qemu-system-x86_64 -m 1G,slots=3,maxmem=4G
378@end example
379
380If @var{slots} and @var{maxmem} are not specified, memory hotplug won't
381be enabled and the guest startup RAM will never increase.
382ETEXI
383
384DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
385    "-mem-path FILE  provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
386STEXI
387@item -mem-path @var{path}
388@findex -mem-path
389Allocate guest RAM from a temporarily created file in @var{path}.
390ETEXI
391
392DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
393    "-mem-prealloc   preallocate guest memory (use with -mem-path)\n",
394    QEMU_ARCH_ALL)
395STEXI
396@item -mem-prealloc
397@findex -mem-prealloc
398Preallocate memory when using -mem-path.
399ETEXI
400
401DEF("k", HAS_ARG, QEMU_OPTION_k,
402    "-k language     use keyboard layout (for example 'fr' for French)\n",
403    QEMU_ARCH_ALL)
404STEXI
405@item -k @var{language}
406@findex -k
407Use keyboard layout @var{language} (for example @code{fr} for
408French). This option is only needed where it is not easy to get raw PC
409keycodes (e.g. on Macs, with some X11 servers or with a VNC or curses
410display). You don't normally need to use it on PC/Linux or PC/Windows
411hosts.
412
413The available layouts are:
414@example
415ar  de-ch  es  fo     fr-ca  hu  ja  mk     no  pt-br  sv
416da  en-gb  et  fr     fr-ch  is  lt  nl     pl  ru     th
417de  en-us  fi  fr-be  hr     it  lv  nl-be  pt  sl     tr
418@end example
419
420The default is @code{en-us}.
421ETEXI
422
423
424DEF("audio-help", 0, QEMU_OPTION_audio_help,
425    "-audio-help     print list of audio drivers and their options\n",
426    QEMU_ARCH_ALL)
427STEXI
428@item -audio-help
429@findex -audio-help
430Will show the audio subsystem help: list of drivers, tunable
431parameters.
432ETEXI
433
434DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
435    "-soundhw c1,... enable audio support\n"
436    "                and only specified sound cards (comma separated list)\n"
437    "                use '-soundhw help' to get the list of supported cards\n"
438    "                use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL)
439STEXI
440@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
441@findex -soundhw
442Enable audio and selected sound hardware. Use 'help' to print all
443available sound hardware.
444
445@example
446qemu-system-i386 -soundhw sb16,adlib disk.img
447qemu-system-i386 -soundhw es1370 disk.img
448qemu-system-i386 -soundhw ac97 disk.img
449qemu-system-i386 -soundhw hda disk.img
450qemu-system-i386 -soundhw all disk.img
451qemu-system-i386 -soundhw help
452@end example
453
454Note that Linux's i810_audio OSS kernel (for AC97) module might
455require manually specifying clocking.
456
457@example
458modprobe i810_audio clocking=48000
459@end example
460ETEXI
461
462DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
463    "-balloon none   disable balloon device\n"
464    "-balloon virtio[,addr=str]\n"
465    "                enable virtio balloon device (default)\n", QEMU_ARCH_ALL)
466STEXI
467@item -balloon none
468@findex -balloon
469Disable balloon device.
470@item -balloon virtio[,addr=@var{addr}]
471Enable virtio balloon device (default), optionally with PCI address
472@var{addr}.
473ETEXI
474
475DEF("device", HAS_ARG, QEMU_OPTION_device,
476    "-device driver[,prop[=value][,...]]\n"
477    "                add device (based on driver)\n"
478    "                prop=value,... sets driver properties\n"
479    "                use '-device help' to print all possible drivers\n"
480    "                use '-device driver,help' to print all possible properties\n",
481    QEMU_ARCH_ALL)
482STEXI
483@item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
484@findex -device
485Add device @var{driver}.  @var{prop}=@var{value} sets driver
486properties.  Valid properties depend on the driver.  To get help on
487possible drivers and properties, use @code{-device help} and
488@code{-device @var{driver},help}.
489
490Some drivers are:
491@item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}][,sdrfile=@var{file}][,furareasize=@var{val}][,furdatafile=@var{file}]
492
493Add an IPMI BMC.  This is a simulation of a hardware management
494interface processor that normally sits on a system.  It provides
495a watchdog and the ability to reset and power control the system.
496You need to connect this to an IPMI interface to make it useful
497
498The IPMI slave address to use for the BMC.  The default is 0x20.
499This address is the BMC's address on the I2C network of management
500controllers.  If you don't know what this means, it is safe to ignore
501it.
502
503@table @option
504@item bmc=@var{id}
505The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
506@item slave_addr=@var{val}
507Define slave address to use for the BMC.  The default is 0x20.
508@item sdrfile=@var{file}
509file containing raw Sensor Data Records (SDR) data. The default is none.
510@item fruareasize=@var{val}
511size of a Field Replaceable Unit (FRU) area.  The default is 1024.
512@item frudatafile=@var{file}
513file containing raw Field Replaceable Unit (FRU) inventory data. The default is none.
514@end table
515
516@item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}]
517
518Add a connection to an external IPMI BMC simulator.  Instead of
519locally emulating the BMC like the above item, instead connect
520to an external entity that provides the IPMI services.
521
522A connection is made to an external BMC simulator.  If you do this, it
523is strongly recommended that you use the "reconnect=" chardev option
524to reconnect to the simulator if the connection is lost.  Note that if
525this is not used carefully, it can be a security issue, as the
526interface has the ability to send resets, NMIs, and power off the VM.
527It's best if QEMU makes a connection to an external simulator running
528on a secure port on localhost, so neither the simulator nor QEMU is
529exposed to any outside network.
530
531See the "lanserv/README.vm" file in the OpenIPMI library for more
532details on the external interface.
533
534@item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
535
536Add a KCS IPMI interafce on the ISA bus.  This also adds a
537corresponding ACPI and SMBIOS entries, if appropriate.
538
539@table @option
540@item bmc=@var{id}
541The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
542@item ioport=@var{val}
543Define the I/O address of the interface.  The default is 0xca0 for KCS.
544@item irq=@var{val}
545Define the interrupt to use.  The default is 5.  To disable interrupts,
546set this to 0.
547@end table
548
549@item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
550
551Like the KCS interface, but defines a BT interface.  The default port is
5520xe4 and the default interrupt is 5.
553
554ETEXI
555
556DEF("name", HAS_ARG, QEMU_OPTION_name,
557    "-name string1[,process=string2][,debug-threads=on|off]\n"
558    "                set the name of the guest\n"
559    "                string1 sets the window title and string2 the process name (on Linux)\n"
560    "                When debug-threads is enabled, individual threads are given a separate name (on Linux)\n"
561    "                NOTE: The thread names are for debugging and not a stable API.\n",
562    QEMU_ARCH_ALL)
563STEXI
564@item -name @var{name}
565@findex -name
566Sets the @var{name} of the guest.
567This name will be displayed in the SDL window caption.
568The @var{name} will also be used for the VNC server.
569Also optionally set the top visible process name in Linux.
570Naming of individual threads can also be enabled on Linux to aid debugging.
571ETEXI
572
573DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
574    "-uuid %08x-%04x-%04x-%04x-%012x\n"
575    "                specify machine UUID\n", QEMU_ARCH_ALL)
576STEXI
577@item -uuid @var{uuid}
578@findex -uuid
579Set system UUID.
580ETEXI
581
582STEXI
583@end table
584ETEXI
585DEFHEADING()
586
587DEFHEADING(Block device options)
588STEXI
589@table @option
590ETEXI
591
592DEF("fda", HAS_ARG, QEMU_OPTION_fda,
593    "-fda/-fdb file  use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
594DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
595STEXI
596@item -fda @var{file}
597@itemx -fdb @var{file}
598@findex -fda
599@findex -fdb
600Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}).
601ETEXI
602
603DEF("hda", HAS_ARG, QEMU_OPTION_hda,
604    "-hda/-hdb file  use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
605DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
606DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
607    "-hdc/-hdd file  use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
608DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
609STEXI
610@item -hda @var{file}
611@itemx -hdb @var{file}
612@itemx -hdc @var{file}
613@itemx -hdd @var{file}
614@findex -hda
615@findex -hdb
616@findex -hdc
617@findex -hdd
618Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
619ETEXI
620
621DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
622    "-cdrom file     use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
623    QEMU_ARCH_ALL)
624STEXI
625@item -cdrom @var{file}
626@findex -cdrom
627Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
628@option{-cdrom} at the same time). You can use the host CD-ROM by
629using @file{/dev/cdrom} as filename (@pxref{host_drives}).
630ETEXI
631
632DEF("blockdev", HAS_ARG, QEMU_OPTION_blockdev,
633    "-blockdev [driver=]driver[,node-name=N][,discard=ignore|unmap]\n"
634    "          [,cache.direct=on|off][,cache.no-flush=on|off]\n"
635    "          [,read-only=on|off][,detect-zeroes=on|off|unmap]\n"
636    "          [,driver specific parameters...]\n"
637    "                configure a block backend\n", QEMU_ARCH_ALL)
638STEXI
639@item -blockdev @var{option}[,@var{option}[,@var{option}[,...]]]
640@findex -blockdev
641
642Define a new block driver node. Some of the options apply to all block drivers,
643other options are only accepted for a specific block driver. See below for a
644list of generic options and options for the most common block drivers.
645
646Options that expect a reference to another node (e.g. @code{file}) can be
647given in two ways. Either you specify the node name of an already existing node
648(file=@var{node-name}), or you define a new node inline, adding options
649for the referenced node after a dot (file.filename=@var{path},file.aio=native).
650
651A block driver node created with @option{-blockdev} can be used for a guest
652device by specifying its node name for the @code{drive} property in a
653@option{-device} argument that defines a block device.
654
655@table @option
656@item Valid options for any block driver node:
657
658@table @code
659@item driver
660Specifies the block driver to use for the given node.
661@item node-name
662This defines the name of the block driver node by which it will be referenced
663later. The name must be unique, i.e. it must not match the name of a different
664block driver node, or (if you use @option{-drive} as well) the ID of a drive.
665
666If no node name is specified, it is automatically generated. The generated node
667name is not intended to be predictable and changes between QEMU invocations.
668For the top level, an explicit node name must be specified.
669@item read-only
670Open the node read-only. Guest write attempts will fail.
671@item cache.direct
672The host page cache can be avoided with @option{cache.direct=on}. This will
673attempt to do disk IO directly to the guest's memory. QEMU may still perform an
674internal copy of the data.
675@item cache.no-flush
676In case you don't care about data integrity over host failures, you can use
677@option{cache.no-flush=on}. This option tells QEMU that it never needs to write
678any data to the disk but can instead keep things in cache. If anything goes
679wrong, like your host losing power, the disk storage getting disconnected
680accidentally, etc. your image will most probably be rendered unusable.
681@item discard=@var{discard}
682@var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls
683whether @code{discard} (also known as @code{trim} or @code{unmap}) requests are
684ignored or passed to the filesystem. Some machine types may not support
685discard requests.
686@item detect-zeroes=@var{detect-zeroes}
687@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic
688conversion of plain zero writes by the OS to driver specific optimized
689zero write commands. You may even choose "unmap" if @var{discard} is set
690to "unmap" to allow a zero write to be converted to an @code{unmap} operation.
691@end table
692
693@item Driver-specific options for @code{file}
694
695This is the protocol-level block driver for accessing regular files.
696
697@table @code
698@item filename
699The path to the image file in the local filesystem
700@item aio
701Specifies the AIO backend (threads/native, default: threads)
702@item locking
703Specifies whether the image file is protected with Linux OFD / POSIX locks. The
704default is to use the Linux Open File Descriptor API if available, otherwise no
705lock is applied.  (auto/on/off, default: auto)
706@end table
707Example:
708@example
709-blockdev driver=file,node-name=disk,filename=disk.img
710@end example
711
712@item Driver-specific options for @code{raw}
713
714This is the image format block driver for raw images. It is usually
715stacked on top of a protocol level block driver such as @code{file}.
716
717@table @code
718@item file
719Reference to or definition of the data source block driver node
720(e.g. a @code{file} driver node)
721@end table
722Example 1:
723@example
724-blockdev driver=file,node-name=disk_file,filename=disk.img
725-blockdev driver=raw,node-name=disk,file=disk_file
726@end example
727Example 2:
728@example
729-blockdev driver=raw,node-name=disk,file.driver=file,file.filename=disk.img
730@end example
731
732@item Driver-specific options for @code{qcow2}
733
734This is the image format block driver for qcow2 images. It is usually
735stacked on top of a protocol level block driver such as @code{file}.
736
737@table @code
738@item file
739Reference to or definition of the data source block driver node
740(e.g. a @code{file} driver node)
741
742@item backing
743Reference to or definition of the backing file block device (default is taken
744from the image file). It is allowed to pass an empty string here in order to
745disable the default backing file.
746
747@item lazy-refcounts
748Whether to enable the lazy refcounts feature (on/off; default is taken from the
749image file)
750
751@item cache-size
752The maximum total size of the L2 table and refcount block caches in bytes
753(default: 1048576 bytes or 8 clusters, whichever is larger)
754
755@item l2-cache-size
756The maximum size of the L2 table cache in bytes
757(default: 4/5 of the total cache size)
758
759@item refcount-cache-size
760The maximum size of the refcount block cache in bytes
761(default: 1/5 of the total cache size)
762
763@item cache-clean-interval
764Clean unused entries in the L2 and refcount caches. The interval is in seconds.
765The default value is 0 and it disables this feature.
766
767@item pass-discard-request
768Whether discard requests to the qcow2 device should be forwarded to the data
769source (on/off; default: on if discard=unmap is specified, off otherwise)
770
771@item pass-discard-snapshot
772Whether discard requests for the data source should be issued when a snapshot
773operation (e.g. deleting a snapshot) frees clusters in the qcow2 file (on/off;
774default: on)
775
776@item pass-discard-other
777Whether discard requests for the data source should be issued on other
778occasions where a cluster gets freed (on/off; default: off)
779
780@item overlap-check
781Which overlap checks to perform for writes to the image
782(none/constant/cached/all; default: cached). For details or finer
783granularity control refer to the QAPI documentation of @code{blockdev-add}.
784@end table
785
786Example 1:
787@example
788-blockdev driver=file,node-name=my_file,filename=/tmp/disk.qcow2
789-blockdev driver=qcow2,node-name=hda,file=my_file,overlap-check=none,cache-size=16777216
790@end example
791Example 2:
792@example
793-blockdev driver=qcow2,node-name=disk,file.driver=http,file.filename=http://example.com/image.qcow2
794@end example
795
796@item Driver-specific options for other drivers
797Please refer to the QAPI documentation of the @code{blockdev-add} QMP command.
798
799@end table
800
801ETEXI
802
803DEF("drive", HAS_ARG, QEMU_OPTION_drive,
804    "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
805    "       [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
806    "       [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
807    "       [,serial=s][,addr=A][,rerror=ignore|stop|report]\n"
808    "       [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n"
809    "       [,readonly=on|off][,copy-on-read=on|off]\n"
810    "       [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n"
811    "       [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n"
812    "       [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n"
813    "       [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n"
814    "       [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n"
815    "       [[,iops_size=is]]\n"
816    "       [[,group=g]]\n"
817    "                use 'file' as a drive image\n", QEMU_ARCH_ALL)
818STEXI
819@item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
820@findex -drive
821
822Define a new drive. This includes creating a block driver node (the backend) as
823well as a guest device, and is mostly a shortcut for defining the corresponding
824@option{-blockdev} and @option{-device} options.
825
826@option{-drive} accepts all options that are accepted by @option{-blockdev}. In
827addition, it knows the following options:
828
829@table @option
830@item file=@var{file}
831This option defines which disk image (@pxref{disk_images}) to use with
832this drive. If the filename contains comma, you must double it
833(for instance, "file=my,,file" to use file "my,file").
834
835Special files such as iSCSI devices can be specified using protocol
836specific URLs. See the section for "Device URL Syntax" for more information.
837@item if=@var{interface}
838This option defines on which type on interface the drive is connected.
839Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio, none.
840@item bus=@var{bus},unit=@var{unit}
841These options define where is connected the drive by defining the bus number and
842the unit id.
843@item index=@var{index}
844This option defines where is connected the drive by using an index in the list
845of available connectors of a given interface type.
846@item media=@var{media}
847This option defines the type of the media: disk or cdrom.
848@item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
849These options have the same definition as they have in @option{-hdachs}.
850These parameters are deprecated, use the corresponding parameters
851of @code{-device} instead.
852@item snapshot=@var{snapshot}
853@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive
854(see @option{-snapshot}).
855@item cache=@var{cache}
856@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough"
857and controls how the host cache is used to access block data. This is a
858shortcut that sets the @option{cache.direct} and @option{cache.no-flush}
859options (as in @option{-blockdev}), and additionally @option{cache.writeback},
860which provides a default for the @option{write-cache} option of block guest
861devices (as in @option{-device}). The modes correspond to the following
862settings:
863
864@c Our texi2pod.pl script doesn't support @multitable, so fall back to using
865@c plain ASCII art (well, UTF-8 art really). This looks okay both in the manpage
866@c and the HTML output.
867@example
868@             │ cache.writeback   cache.direct   cache.no-flush
869─────────────┼─────────────────────────────────────────────────
870writeback    │ on                off            off
871none         │ on                on             off
872writethrough │ off               off            off
873directsync   │ off               on             off
874unsafe       │ on                off            on
875@end example
876
877The default mode is @option{cache=writeback}.
878
879@item aio=@var{aio}
880@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
881@item format=@var{format}
882Specify which disk @var{format} will be used rather than detecting
883the format.  Can be used to specify format=raw to avoid interpreting
884an untrusted format header.
885@item serial=@var{serial}
886This option specifies the serial number to assign to the device. This
887parameter is deprecated, use the corresponding parameter of @code{-device}
888instead.
889@item addr=@var{addr}
890Specify the controller's PCI address (if=virtio only). This parameter is
891deprecated, use the corresponding parameter of @code{-device} instead.
892@item werror=@var{action},rerror=@var{action}
893Specify which @var{action} to take on write and read errors. Valid actions are:
894"ignore" (ignore the error and try to continue), "stop" (pause QEMU),
895"report" (report the error to the guest), "enospc" (pause QEMU only if the
896host disk is full; report the error to the guest otherwise).
897The default setting is @option{werror=enospc} and @option{rerror=report}.
898@item copy-on-read=@var{copy-on-read}
899@var{copy-on-read} is "on" or "off" and enables whether to copy read backing
900file sectors into the image file.
901@item bps=@var{b},bps_rd=@var{r},bps_wr=@var{w}
902Specify bandwidth throttling limits in bytes per second, either for all request
903types or for reads or writes only.  Small values can lead to timeouts or hangs
904inside the guest.  A safe minimum for disks is 2 MB/s.
905@item bps_max=@var{bm},bps_rd_max=@var{rm},bps_wr_max=@var{wm}
906Specify bursts in bytes per second, either for all request types or for reads
907or writes only.  Bursts allow the guest I/O to spike above the limit
908temporarily.
909@item iops=@var{i},iops_rd=@var{r},iops_wr=@var{w}
910Specify request rate limits in requests per second, either for all request
911types or for reads or writes only.
912@item iops_max=@var{bm},iops_rd_max=@var{rm},iops_wr_max=@var{wm}
913Specify bursts in requests per second, either for all request types or for reads
914or writes only.  Bursts allow the guest I/O to spike above the limit
915temporarily.
916@item iops_size=@var{is}
917Let every @var{is} bytes of a request count as a new request for iops
918throttling purposes.  Use this option to prevent guests from circumventing iops
919limits by sending fewer but larger requests.
920@item group=@var{g}
921Join a throttling quota group with given name @var{g}.  All drives that are
922members of the same group are accounted for together.  Use this option to
923prevent guests from circumventing throttling limits by using many small disks
924instead of a single larger disk.
925@end table
926
927By default, the @option{cache.writeback=on} mode is used. It will report data
928writes as completed as soon as the data is present in the host page cache.
929This is safe as long as your guest OS makes sure to correctly flush disk caches
930where needed. If your guest OS does not handle volatile disk write caches
931correctly and your host crashes or loses power, then the guest may experience
932data corruption.
933
934For such guests, you should consider using @option{cache.writeback=off}. This
935means that the host page cache will be used to read and write data, but write
936notification will be sent to the guest only after QEMU has made sure to flush
937each write to the disk. Be aware that this has a major impact on performance.
938
939When using the @option{-snapshot} option, unsafe caching is always used.
940
941Copy-on-read avoids accessing the same backing file sectors repeatedly and is
942useful when the backing file is over a slow network.  By default copy-on-read
943is off.
944
945Instead of @option{-cdrom} you can use:
946@example
947qemu-system-i386 -drive file=file,index=2,media=cdrom
948@end example
949
950Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
951use:
952@example
953qemu-system-i386 -drive file=file,index=0,media=disk
954qemu-system-i386 -drive file=file,index=1,media=disk
955qemu-system-i386 -drive file=file,index=2,media=disk
956qemu-system-i386 -drive file=file,index=3,media=disk
957@end example
958
959You can open an image using pre-opened file descriptors from an fd set:
960@example
961qemu-system-i386
962-add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
963-add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
964-drive file=/dev/fdset/2,index=0,media=disk
965@end example
966
967You can connect a CDROM to the slave of ide0:
968@example
969qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
970@end example
971
972If you don't specify the "file=" argument, you define an empty drive:
973@example
974qemu-system-i386 -drive if=ide,index=1,media=cdrom
975@end example
976
977Instead of @option{-fda}, @option{-fdb}, you can use:
978@example
979qemu-system-i386 -drive file=file,index=0,if=floppy
980qemu-system-i386 -drive file=file,index=1,if=floppy
981@end example
982
983By default, @var{interface} is "ide" and @var{index} is automatically
984incremented:
985@example
986qemu-system-i386 -drive file=a -drive file=b"
987@end example
988is interpreted like:
989@example
990qemu-system-i386 -hda a -hdb b
991@end example
992ETEXI
993
994DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
995    "-mtdblock file  use 'file' as on-board Flash memory image\n",
996    QEMU_ARCH_ALL)
997STEXI
998@item -mtdblock @var{file}
999@findex -mtdblock
1000Use @var{file} as on-board Flash memory image.
1001ETEXI
1002
1003DEF("sd", HAS_ARG, QEMU_OPTION_sd,
1004    "-sd file        use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL)
1005STEXI
1006@item -sd @var{file}
1007@findex -sd
1008Use @var{file} as SecureDigital card image.
1009ETEXI
1010
1011DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
1012    "-pflash file    use 'file' as a parallel flash image\n", QEMU_ARCH_ALL)
1013STEXI
1014@item -pflash @var{file}
1015@findex -pflash
1016Use @var{file} as a parallel flash image.
1017ETEXI
1018
1019DEF("snapshot", 0, QEMU_OPTION_snapshot,
1020    "-snapshot       write to temporary files instead of disk image files\n",
1021    QEMU_ARCH_ALL)
1022STEXI
1023@item -snapshot
1024@findex -snapshot
1025Write to temporary files instead of disk image files. In this case,
1026the raw disk image you use is not written back. You can however force
1027the write back by pressing @key{C-a s} (@pxref{disk_images}).
1028ETEXI
1029
1030DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
1031    "-hdachs c,h,s[,t]\n" \
1032    "                force hard disk 0 physical geometry and the optional BIOS\n" \
1033    "                translation (t=none or lba) (usually QEMU can guess them)\n",
1034    QEMU_ARCH_ALL)
1035STEXI
1036@item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
1037@findex -hdachs
1038Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
1039@var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
1040translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
1041all those parameters. This option is deprecated, please use
1042@code{-device ide-hd,cyls=c,heads=h,secs=s,...} instead.
1043ETEXI
1044
1045DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
1046    "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
1047    " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n"
1048    " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n"
1049    " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n"
1050    " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n"
1051    " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n"
1052    " [[,throttling.iops-size=is]]\n",
1053    QEMU_ARCH_ALL)
1054
1055STEXI
1056
1057@item -fsdev @var{fsdriver},id=@var{id},path=@var{path},[security_model=@var{security_model}][,writeout=@var{writeout}][,readonly][,socket=@var{socket}|sock_fd=@var{sock_fd}][,fmode=@var{fmode}][,dmode=@var{dmode}]
1058@findex -fsdev
1059Define a new file system device. Valid options are:
1060@table @option
1061@item @var{fsdriver}
1062This option specifies the fs driver backend to use.
1063Currently "local", "handle" and "proxy" file system drivers are supported.
1064@item id=@var{id}
1065Specifies identifier for this device
1066@item path=@var{path}
1067Specifies the export path for the file system device. Files under
1068this path will be available to the 9p client on the guest.
1069@item security_model=@var{security_model}
1070Specifies the security model to be used for this export path.
1071Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
1072In "passthrough" security model, files are stored using the same
1073credentials as they are created on the guest. This requires QEMU
1074to run as root. In "mapped-xattr" security model, some of the file
1075attributes like uid, gid, mode bits and link target are stored as
1076file attributes. For "mapped-file" these attributes are stored in the
1077hidden .virtfs_metadata directory. Directories exported by this security model cannot
1078interact with other unix tools. "none" security model is same as
1079passthrough except the sever won't report failures if it fails to
1080set file attributes like ownership. Security model is mandatory
1081only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
1082security model as a parameter.
1083@item writeout=@var{writeout}
1084This is an optional argument. The only supported value is "immediate".
1085This means that host page cache will be used to read and write data but
1086write notification will be sent to the guest only when the data has been
1087reported as written by the storage subsystem.
1088@item readonly
1089Enables exporting 9p share as a readonly mount for guests. By default
1090read-write access is given.
1091@item socket=@var{socket}
1092Enables proxy filesystem driver to use passed socket file for communicating
1093with virtfs-proxy-helper
1094@item sock_fd=@var{sock_fd}
1095Enables proxy filesystem driver to use passed socket descriptor for
1096communicating with virtfs-proxy-helper. Usually a helper like libvirt
1097will create socketpair and pass one of the fds as sock_fd
1098@item fmode=@var{fmode}
1099Specifies the default mode for newly created files on the host. Works only
1100with security models "mapped-xattr" and "mapped-file".
1101@item dmode=@var{dmode}
1102Specifies the default mode for newly created directories on the host. Works
1103only with security models "mapped-xattr" and "mapped-file".
1104@end table
1105
1106-fsdev option is used along with -device driver "virtio-9p-pci".
1107@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
1108Options for virtio-9p-pci driver are:
1109@table @option
1110@item fsdev=@var{id}
1111Specifies the id value specified along with -fsdev option
1112@item mount_tag=@var{mount_tag}
1113Specifies the tag name to be used by the guest to mount this export point
1114@end table
1115
1116ETEXI
1117
1118DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
1119    "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
1120    "        [,id=id][,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n",
1121    QEMU_ARCH_ALL)
1122
1123STEXI
1124
1125@item -virtfs @var{fsdriver}[,path=@var{path}],mount_tag=@var{mount_tag}[,security_model=@var{security_model}][,writeout=@var{writeout}][,readonly][,socket=@var{socket}|sock_fd=@var{sock_fd}][,fmode=@var{fmode}][,dmode=@var{dmode}]
1126@findex -virtfs
1127
1128The general form of a Virtual File system pass-through options are:
1129@table @option
1130@item @var{fsdriver}
1131This option specifies the fs driver backend to use.
1132Currently "local", "handle" and "proxy" file system drivers are supported.
1133@item id=@var{id}
1134Specifies identifier for this device
1135@item path=@var{path}
1136Specifies the export path for the file system device. Files under
1137this path will be available to the 9p client on the guest.
1138@item security_model=@var{security_model}
1139Specifies the security model to be used for this export path.
1140Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
1141In "passthrough" security model, files are stored using the same
1142credentials as they are created on the guest. This requires QEMU
1143to run as root. In "mapped-xattr" security model, some of the file
1144attributes like uid, gid, mode bits and link target are stored as
1145file attributes. For "mapped-file" these attributes are stored in the
1146hidden .virtfs_metadata directory. Directories exported by this security model cannot
1147interact with other unix tools. "none" security model is same as
1148passthrough except the sever won't report failures if it fails to
1149set file attributes like ownership. Security model is mandatory only
1150for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
1151model as a parameter.
1152@item writeout=@var{writeout}
1153This is an optional argument. The only supported value is "immediate".
1154This means that host page cache will be used to read and write data but
1155write notification will be sent to the guest only when the data has been
1156reported as written by the storage subsystem.
1157@item readonly
1158Enables exporting 9p share as a readonly mount for guests. By default
1159read-write access is given.
1160@item socket=@var{socket}
1161Enables proxy filesystem driver to use passed socket file for
1162communicating with virtfs-proxy-helper. Usually a helper like libvirt
1163will create socketpair and pass one of the fds as sock_fd
1164@item sock_fd
1165Enables proxy filesystem driver to use passed 'sock_fd' as the socket
1166descriptor for interfacing with virtfs-proxy-helper
1167@item fmode=@var{fmode}
1168Specifies the default mode for newly created files on the host. Works only
1169with security models "mapped-xattr" and "mapped-file".
1170@item dmode=@var{dmode}
1171Specifies the default mode for newly created directories on the host. Works
1172only with security models "mapped-xattr" and "mapped-file".
1173@end table
1174ETEXI
1175
1176DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
1177    "-virtfs_synth Create synthetic file system image\n",
1178    QEMU_ARCH_ALL)
1179STEXI
1180@item -virtfs_synth
1181@findex -virtfs_synth
1182Create synthetic file system image
1183ETEXI
1184
1185STEXI
1186@end table
1187ETEXI
1188DEFHEADING()
1189
1190DEFHEADING(USB options)
1191STEXI
1192@table @option
1193ETEXI
1194
1195DEF("usb", 0, QEMU_OPTION_usb,
1196    "-usb            enable the USB driver (if it is not used by default yet)\n",
1197    QEMU_ARCH_ALL)
1198STEXI
1199@item -usb
1200@findex -usb
1201Enable the USB driver (if it is not used by default yet).
1202ETEXI
1203
1204DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
1205    "-usbdevice name add the host or guest USB device 'name'\n",
1206    QEMU_ARCH_ALL)
1207STEXI
1208
1209@item -usbdevice @var{devname}
1210@findex -usbdevice
1211Add the USB device @var{devname}. Note that this option is deprecated,
1212please use @code{-device usb-...} instead. @xref{usb_devices}.
1213
1214@table @option
1215
1216@item mouse
1217Virtual Mouse. This will override the PS/2 mouse emulation when activated.
1218
1219@item tablet
1220Pointer device that uses absolute coordinates (like a touchscreen). This
1221means QEMU is able to report the mouse position without having to grab the
1222mouse. Also overrides the PS/2 mouse emulation when activated.
1223
1224@item disk:[format=@var{format}]:@var{file}
1225Mass storage device based on file. The optional @var{format} argument
1226will be used rather than detecting the format. Can be used to specify
1227@code{format=raw} to avoid interpreting an untrusted format header.
1228
1229@item host:@var{bus}.@var{addr}
1230Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
1231
1232@item host:@var{vendor_id}:@var{product_id}
1233Pass through the host device identified by @var{vendor_id}:@var{product_id}
1234(Linux only).
1235
1236@item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
1237Serial converter to host character device @var{dev}, see @code{-serial} for the
1238available devices.
1239
1240@item braille
1241Braille device.  This will use BrlAPI to display the braille output on a real
1242or fake device.
1243
1244@item net:@var{options}
1245Network adapter that supports CDC ethernet and RNDIS protocols.
1246
1247@end table
1248ETEXI
1249
1250STEXI
1251@end table
1252ETEXI
1253DEFHEADING()
1254
1255DEFHEADING(Display options)
1256STEXI
1257@table @option
1258ETEXI
1259
1260DEF("display", HAS_ARG, QEMU_OPTION_display,
1261    "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
1262    "            [,window_close=on|off][,gl=on|off]\n"
1263    "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n"
1264    "-display vnc=<display>[,<optargs>]\n"
1265    "-display curses\n"
1266    "-display none"
1267    "                select display type\n"
1268    "The default display is equivalent to\n"
1269#if defined(CONFIG_GTK)
1270            "\t\"-display gtk\"\n"
1271#elif defined(CONFIG_SDL)
1272            "\t\"-display sdl\"\n"
1273#elif defined(CONFIG_COCOA)
1274            "\t\"-display cocoa\"\n"
1275#elif defined(CONFIG_VNC)
1276            "\t\"-vnc localhost:0,to=99,id=default\"\n"
1277#else
1278            "\t\"-display none\"\n"
1279#endif
1280    , QEMU_ARCH_ALL)
1281STEXI
1282@item -display @var{type}
1283@findex -display
1284Select type of display to use. This option is a replacement for the
1285old style -sdl/-curses/... options. Valid values for @var{type} are
1286@table @option
1287@item sdl
1288Display video output via SDL (usually in a separate graphics
1289window; see the SDL documentation for other possibilities).
1290@item curses
1291Display video output via curses. For graphics device models which
1292support a text mode, QEMU can display this output using a
1293curses/ncurses interface. Nothing is displayed when the graphics
1294device is in graphical mode or if the graphics device does not support
1295a text mode. Generally only the VGA device models support text mode.
1296@item none
1297Do not display video output. The guest will still see an emulated
1298graphics card, but its output will not be displayed to the QEMU
1299user. This option differs from the -nographic option in that it
1300only affects what is done with video output; -nographic also changes
1301the destination of the serial and parallel port data.
1302@item gtk
1303Display video output in a GTK window. This interface provides drop-down
1304menus and other UI elements to configure and control the VM during
1305runtime.
1306@item vnc
1307Start a VNC server on display <arg>
1308@end table
1309ETEXI
1310
1311DEF("nographic", 0, QEMU_OPTION_nographic,
1312    "-nographic      disable graphical output and redirect serial I/Os to console\n",
1313    QEMU_ARCH_ALL)
1314STEXI
1315@item -nographic
1316@findex -nographic
1317Normally, if QEMU is compiled with graphical window support, it displays
1318output such as guest graphics, guest console, and the QEMU monitor in a
1319window. With this option, you can totally disable graphical output so
1320that QEMU is a simple command line application. The emulated serial port
1321is redirected on the console and muxed with the monitor (unless
1322redirected elsewhere explicitly). Therefore, you can still use QEMU to
1323debug a Linux kernel with a serial console. Use @key{C-a h} for help on
1324switching between the console and monitor.
1325ETEXI
1326
1327DEF("curses", 0, QEMU_OPTION_curses,
1328    "-curses         shorthand for -display curses\n",
1329    QEMU_ARCH_ALL)
1330STEXI
1331@item -curses
1332@findex -curses
1333Normally, if QEMU is compiled with graphical window support, it displays
1334output such as guest graphics, guest console, and the QEMU monitor in a
1335window. With this option, QEMU can display the VGA output when in text
1336mode using a curses/ncurses interface. Nothing is displayed in graphical
1337mode.
1338ETEXI
1339
1340DEF("no-frame", 0, QEMU_OPTION_no_frame,
1341    "-no-frame       open SDL window without a frame and window decorations\n",
1342    QEMU_ARCH_ALL)
1343STEXI
1344@item -no-frame
1345@findex -no-frame
1346Do not use decorations for SDL windows and start them using the whole
1347available screen space. This makes the using QEMU in a dedicated desktop
1348workspace more convenient.
1349ETEXI
1350
1351DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
1352    "-alt-grab       use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
1353    QEMU_ARCH_ALL)
1354STEXI
1355@item -alt-grab
1356@findex -alt-grab
1357Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
1358affects the special keys (for fullscreen, monitor-mode switching, etc).
1359ETEXI
1360
1361DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
1362    "-ctrl-grab      use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
1363    QEMU_ARCH_ALL)
1364STEXI
1365@item -ctrl-grab
1366@findex -ctrl-grab
1367Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
1368affects the special keys (for fullscreen, monitor-mode switching, etc).
1369ETEXI
1370
1371DEF("no-quit", 0, QEMU_OPTION_no_quit,
1372    "-no-quit        disable SDL window close capability\n", QEMU_ARCH_ALL)
1373STEXI
1374@item -no-quit
1375@findex -no-quit
1376Disable SDL window close capability.
1377ETEXI
1378
1379DEF("sdl", 0, QEMU_OPTION_sdl,
1380    "-sdl            shorthand for -display sdl\n", QEMU_ARCH_ALL)
1381STEXI
1382@item -sdl
1383@findex -sdl
1384Enable SDL.
1385ETEXI
1386
1387DEF("spice", HAS_ARG, QEMU_OPTION_spice,
1388    "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
1389    "       [,x509-key-file=<file>][,x509-key-password=<file>]\n"
1390    "       [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
1391    "       [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n"
1392    "       [,tls-ciphers=<list>]\n"
1393    "       [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
1394    "       [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
1395    "       [,sasl][,password=<secret>][,disable-ticketing]\n"
1396    "       [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
1397    "       [,jpeg-wan-compression=[auto|never|always]]\n"
1398    "       [,zlib-glz-wan-compression=[auto|never|always]]\n"
1399    "       [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
1400    "       [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
1401    "       [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
1402    "       [,gl=[on|off]][,rendernode=<file>]\n"
1403    "   enable spice\n"
1404    "   at least one of {port, tls-port} is mandatory\n",
1405    QEMU_ARCH_ALL)
1406STEXI
1407@item -spice @var{option}[,@var{option}[,...]]
1408@findex -spice
1409Enable the spice remote desktop protocol. Valid options are
1410
1411@table @option
1412
1413@item port=<nr>
1414Set the TCP port spice is listening on for plaintext channels.
1415
1416@item addr=<addr>
1417Set the IP address spice is listening on.  Default is any address.
1418
1419@item ipv4
1420@itemx ipv6
1421@itemx unix
1422Force using the specified IP version.
1423
1424@item password=<secret>
1425Set the password you need to authenticate.
1426
1427@item sasl
1428Require that the client use SASL to authenticate with the spice.
1429The exact choice of authentication method used is controlled from the
1430system / user's SASL configuration file for the 'qemu' service. This
1431is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1432unprivileged user, an environment variable SASL_CONF_PATH can be used
1433to make it search alternate locations for the service config.
1434While some SASL auth methods can also provide data encryption (eg GSSAPI),
1435it is recommended that SASL always be combined with the 'tls' and
1436'x509' settings to enable use of SSL and server certificates. This
1437ensures a data encryption preventing compromise of authentication
1438credentials.
1439
1440@item disable-ticketing
1441Allow client connects without authentication.
1442
1443@item disable-copy-paste
1444Disable copy paste between the client and the guest.
1445
1446@item disable-agent-file-xfer
1447Disable spice-vdagent based file-xfer between the client and the guest.
1448
1449@item tls-port=<nr>
1450Set the TCP port spice is listening on for encrypted channels.
1451
1452@item x509-dir=<dir>
1453Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1454
1455@item x509-key-file=<file>
1456@itemx x509-key-password=<file>
1457@itemx x509-cert-file=<file>
1458@itemx x509-cacert-file=<file>
1459@itemx x509-dh-key-file=<file>
1460The x509 file names can also be configured individually.
1461
1462@item tls-ciphers=<list>
1463Specify which ciphers to use.
1464
1465@item tls-channel=[main|display|cursor|inputs|record|playback]
1466@itemx plaintext-channel=[main|display|cursor|inputs|record|playback]
1467Force specific channel to be used with or without TLS encryption.  The
1468options can be specified multiple times to configure multiple
1469channels.  The special name "default" can be used to set the default
1470mode.  For channels which are not explicitly forced into one mode the
1471spice client is allowed to pick tls/plaintext as he pleases.
1472
1473@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1474Configure image compression (lossless).
1475Default is auto_glz.
1476
1477@item jpeg-wan-compression=[auto|never|always]
1478@itemx zlib-glz-wan-compression=[auto|never|always]
1479Configure wan image compression (lossy for slow links).
1480Default is auto.
1481
1482@item streaming-video=[off|all|filter]
1483Configure video stream detection.  Default is off.
1484
1485@item agent-mouse=[on|off]
1486Enable/disable passing mouse events via vdagent.  Default is on.
1487
1488@item playback-compression=[on|off]
1489Enable/disable audio stream compression (using celt 0.5.1).  Default is on.
1490
1491@item seamless-migration=[on|off]
1492Enable/disable spice seamless migration. Default is off.
1493
1494@item gl=[on|off]
1495Enable/disable OpenGL context. Default is off.
1496
1497@item rendernode=<file>
1498DRM render node for OpenGL rendering. If not specified, it will pick
1499the first available. (Since 2.9)
1500
1501@end table
1502ETEXI
1503
1504DEF("portrait", 0, QEMU_OPTION_portrait,
1505    "-portrait       rotate graphical output 90 deg left (only PXA LCD)\n",
1506    QEMU_ARCH_ALL)
1507STEXI
1508@item -portrait
1509@findex -portrait
1510Rotate graphical output 90 deg left (only PXA LCD).
1511ETEXI
1512
1513DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1514    "-rotate <deg>   rotate graphical output some deg left (only PXA LCD)\n",
1515    QEMU_ARCH_ALL)
1516STEXI
1517@item -rotate @var{deg}
1518@findex -rotate
1519Rotate graphical output some deg left (only PXA LCD).
1520ETEXI
1521
1522DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1523    "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n"
1524    "                select video card type\n", QEMU_ARCH_ALL)
1525STEXI
1526@item -vga @var{type}
1527@findex -vga
1528Select type of VGA card to emulate. Valid values for @var{type} are
1529@table @option
1530@item cirrus
1531Cirrus Logic GD5446 Video card. All Windows versions starting from
1532Windows 95 should recognize and use this graphic card. For optimal
1533performances, use 16 bit color depth in the guest and the host OS.
1534(This card was the default before QEMU 2.2)
1535@item std
1536Standard VGA card with Bochs VBE extensions.  If your guest OS
1537supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1538to use high resolution modes (>= 1280x1024x16) then you should use
1539this option. (This card is the default since QEMU 2.2)
1540@item vmware
1541VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1542recent XFree86/XOrg server or Windows guest with a driver for this
1543card.
1544@item qxl
1545QXL paravirtual graphic card.  It is VGA compatible (including VESA
15462.0 VBE support).  Works best with qxl guest drivers installed though.
1547Recommended choice when using the spice protocol.
1548@item tcx
1549(sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1550sun4m machines and offers both 8-bit and 24-bit colour depths at a
1551fixed resolution of 1024x768.
1552@item cg3
1553(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1554for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1555resolutions aimed at people wishing to run older Solaris versions.
1556@item virtio
1557Virtio VGA card.
1558@item none
1559Disable VGA card.
1560@end table
1561ETEXI
1562
1563DEF("full-screen", 0, QEMU_OPTION_full_screen,
1564    "-full-screen    start in full screen\n", QEMU_ARCH_ALL)
1565STEXI
1566@item -full-screen
1567@findex -full-screen
1568Start in full screen.
1569ETEXI
1570
1571DEF("g", 1, QEMU_OPTION_g ,
1572    "-g WxH[xDEPTH]  Set the initial graphical resolution and depth\n",
1573    QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1574STEXI
1575@item -g @var{width}x@var{height}[x@var{depth}]
1576@findex -g
1577Set the initial graphical resolution and depth (PPC, SPARC only).
1578ETEXI
1579
1580DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1581    "-vnc <display>  shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL)
1582STEXI
1583@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1584@findex -vnc
1585Normally, if QEMU is compiled with graphical window support, it displays
1586output such as guest graphics, guest console, and the QEMU monitor in a
1587window. With this option, you can have QEMU listen on VNC display
1588@var{display} and redirect the VGA display over the VNC session. It is
1589very useful to enable the usb tablet device when using this option
1590(option @option{-device usb-tablet}). When using the VNC display, you
1591must use the @option{-k} parameter to set the keyboard layout if you are
1592not using en-us. Valid syntax for the @var{display} is
1593
1594@table @option
1595
1596@item to=@var{L}
1597
1598With this option, QEMU will try next available VNC @var{display}s, until the
1599number @var{L}, if the origianlly defined "-vnc @var{display}" is not
1600available, e.g. port 5900+@var{display} is already used by another
1601application. By default, to=0.
1602
1603@item @var{host}:@var{d}
1604
1605TCP connections will only be allowed from @var{host} on display @var{d}.
1606By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1607be omitted in which case the server will accept connections from any host.
1608
1609@item unix:@var{path}
1610
1611Connections will be allowed over UNIX domain sockets where @var{path} is the
1612location of a unix socket to listen for connections on.
1613
1614@item none
1615
1616VNC is initialized but not started. The monitor @code{change} command
1617can be used to later start the VNC server.
1618
1619@end table
1620
1621Following the @var{display} value there may be one or more @var{option} flags
1622separated by commas. Valid options are
1623
1624@table @option
1625
1626@item reverse
1627
1628Connect to a listening VNC client via a ``reverse'' connection. The
1629client is specified by the @var{display}. For reverse network
1630connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1631is a TCP port number, not a display number.
1632
1633@item websocket
1634
1635Opens an additional TCP listening port dedicated to VNC Websocket connections.
1636If a bare @var{websocket} option is given, the Websocket port is
16375700+@var{display}. An alternative port can be specified with the
1638syntax @code{websocket}=@var{port}.
1639
1640If @var{host} is specified connections will only be allowed from this host.
1641It is possible to control the websocket listen address independently, using
1642the syntax @code{websocket}=@var{host}:@var{port}.
1643
1644If no TLS credentials are provided, the websocket connection runs in
1645unencrypted mode. If TLS credentials are provided, the websocket connection
1646requires encrypted client connections.
1647
1648@item password
1649
1650Require that password based authentication is used for client connections.
1651
1652The password must be set separately using the @code{set_password} command in
1653the @ref{pcsys_monitor}. The syntax to change your password is:
1654@code{set_password <protocol> <password>} where <protocol> could be either
1655"vnc" or "spice".
1656
1657If you would like to change <protocol> password expiration, you should use
1658@code{expire_password <protocol> <expiration-time>} where expiration time could
1659be one of the following options: now, never, +seconds or UNIX time of
1660expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1661to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1662date and time).
1663
1664You can also use keywords "now" or "never" for the expiration time to
1665allow <protocol> password to expire immediately or never expire.
1666
1667@item tls-creds=@var{ID}
1668
1669Provides the ID of a set of TLS credentials to use to secure the
1670VNC server. They will apply to both the normal VNC server socket
1671and the websocket socket (if enabled). Setting TLS credentials
1672will cause the VNC server socket to enable the VeNCrypt auth
1673mechanism.  The credentials should have been previously created
1674using the @option{-object tls-creds} argument.
1675
1676The @option{tls-creds} parameter obsoletes the @option{tls},
1677@option{x509}, and @option{x509verify} options, and as such
1678it is not permitted to set both new and old type options at
1679the same time.
1680
1681@item tls
1682
1683Require that client use TLS when communicating with the VNC server. This
1684uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1685attack. It is recommended that this option be combined with either the
1686@option{x509} or @option{x509verify} options.
1687
1688This option is now deprecated in favor of using the @option{tls-creds}
1689argument.
1690
1691@item x509=@var{/path/to/certificate/dir}
1692
1693Valid if @option{tls} is specified. Require that x509 credentials are used
1694for negotiating the TLS session. The server will send its x509 certificate
1695to the client. It is recommended that a password be set on the VNC server
1696to provide authentication of the client when this is used. The path following
1697this option specifies where the x509 certificates are to be loaded from.
1698See the @ref{vnc_security} section for details on generating certificates.
1699
1700This option is now deprecated in favour of using the @option{tls-creds}
1701argument.
1702
1703@item x509verify=@var{/path/to/certificate/dir}
1704
1705Valid if @option{tls} is specified. Require that x509 credentials are used
1706for negotiating the TLS session. The server will send its x509 certificate
1707to the client, and request that the client send its own x509 certificate.
1708The server will validate the client's certificate against the CA certificate,
1709and reject clients when validation fails. If the certificate authority is
1710trusted, this is a sufficient authentication mechanism. You may still wish
1711to set a password on the VNC server as a second authentication layer. The
1712path following this option specifies where the x509 certificates are to
1713be loaded from. See the @ref{vnc_security} section for details on generating
1714certificates.
1715
1716This option is now deprecated in favour of using the @option{tls-creds}
1717argument.
1718
1719@item sasl
1720
1721Require that the client use SASL to authenticate with the VNC server.
1722The exact choice of authentication method used is controlled from the
1723system / user's SASL configuration file for the 'qemu' service. This
1724is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1725unprivileged user, an environment variable SASL_CONF_PATH can be used
1726to make it search alternate locations for the service config.
1727While some SASL auth methods can also provide data encryption (eg GSSAPI),
1728it is recommended that SASL always be combined with the 'tls' and
1729'x509' settings to enable use of SSL and server certificates. This
1730ensures a data encryption preventing compromise of authentication
1731credentials. See the @ref{vnc_security} section for details on using
1732SASL authentication.
1733
1734@item acl
1735
1736Turn on access control lists for checking of the x509 client certificate
1737and SASL party. For x509 certs, the ACL check is made against the
1738certificate's distinguished name. This is something that looks like
1739@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1740made against the username, which depending on the SASL plugin, may
1741include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1742When the @option{acl} flag is set, the initial access list will be
1743empty, with a @code{deny} policy. Thus no one will be allowed to
1744use the VNC server until the ACLs have been loaded. This can be
1745achieved using the @code{acl} monitor command.
1746
1747@item lossy
1748
1749Enable lossy compression methods (gradient, JPEG, ...). If this
1750option is set, VNC client may receive lossy framebuffer updates
1751depending on its encoding settings. Enabling this option can save
1752a lot of bandwidth at the expense of quality.
1753
1754@item non-adaptive
1755
1756Disable adaptive encodings. Adaptive encodings are enabled by default.
1757An adaptive encoding will try to detect frequently updated screen regions,
1758and send updates in these regions using a lossy encoding (like JPEG).
1759This can be really helpful to save bandwidth when playing videos. Disabling
1760adaptive encodings restores the original static behavior of encodings
1761like Tight.
1762
1763@item share=[allow-exclusive|force-shared|ignore]
1764
1765Set display sharing policy.  'allow-exclusive' allows clients to ask
1766for exclusive access.  As suggested by the rfb spec this is
1767implemented by dropping other connections.  Connecting multiple
1768clients in parallel requires all clients asking for a shared session
1769(vncviewer: -shared switch).  This is the default.  'force-shared'
1770disables exclusive client access.  Useful for shared desktop sessions,
1771where you don't want someone forgetting specify -shared disconnect
1772everybody else.  'ignore' completely ignores the shared flag and
1773allows everybody connect unconditionally.  Doesn't conform to the rfb
1774spec but is traditional QEMU behavior.
1775
1776@item key-delay-ms
1777
1778Set keyboard delay, for key down and key up events, in milliseconds.
1779Default is 10.  Keyboards are low-bandwidth devices, so this slowdown
1780can help the device and guest to keep up and not lose events in case
1781events are arriving in bulk.  Possible causes for the latter are flaky
1782network connections, or scripts for automated testing.
1783
1784@end table
1785ETEXI
1786
1787STEXI
1788@end table
1789ETEXI
1790ARCHHEADING(, QEMU_ARCH_I386)
1791
1792ARCHHEADING(i386 target only, QEMU_ARCH_I386)
1793STEXI
1794@table @option
1795ETEXI
1796
1797DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1798    "-win2k-hack     use it when installing Windows 2000 to avoid a disk full bug\n",
1799    QEMU_ARCH_I386)
1800STEXI
1801@item -win2k-hack
1802@findex -win2k-hack
1803Use it when installing Windows 2000 to avoid a disk full bug. After
1804Windows 2000 is installed, you no longer need this option (this option
1805slows down the IDE transfers).
1806ETEXI
1807
1808HXCOMM Deprecated by -rtc
1809DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1810
1811DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1812    "-no-fd-bootchk  disable boot signature checking for floppy disks\n",
1813    QEMU_ARCH_I386)
1814STEXI
1815@item -no-fd-bootchk
1816@findex -no-fd-bootchk
1817Disable boot signature checking for floppy disks in BIOS. May
1818be needed to boot from old floppy disks.
1819ETEXI
1820
1821DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1822           "-no-acpi        disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1823STEXI
1824@item -no-acpi
1825@findex -no-acpi
1826Disable ACPI (Advanced Configuration and Power Interface) support. Use
1827it if your guest OS complains about ACPI problems (PC target machine
1828only).
1829ETEXI
1830
1831DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1832    "-no-hpet        disable HPET\n", QEMU_ARCH_I386)
1833STEXI
1834@item -no-hpet
1835@findex -no-hpet
1836Disable HPET support.
1837ETEXI
1838
1839DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1840    "-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"
1841    "                ACPI table description\n", QEMU_ARCH_I386)
1842STEXI
1843@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}]...]
1844@findex -acpitable
1845Add ACPI table with specified header fields and context from specified files.
1846For file=, take whole ACPI table from the specified files, including all
1847ACPI headers (possible overridden by other options).
1848For data=, only data
1849portion of the table is used, all header information is specified in the
1850command line.
1851If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id
1852fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order
1853to ensure the field matches required by the Microsoft SLIC spec and the ACPI
1854spec.
1855ETEXI
1856
1857DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1858    "-smbios file=binary\n"
1859    "                load SMBIOS entry from binary file\n"
1860    "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1861    "              [,uefi=on|off]\n"
1862    "                specify SMBIOS type 0 fields\n"
1863    "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1864    "              [,uuid=uuid][,sku=str][,family=str]\n"
1865    "                specify SMBIOS type 1 fields\n"
1866    "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1867    "              [,asset=str][,location=str]\n"
1868    "                specify SMBIOS type 2 fields\n"
1869    "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n"
1870    "              [,sku=str]\n"
1871    "                specify SMBIOS type 3 fields\n"
1872    "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n"
1873    "              [,asset=str][,part=str]\n"
1874    "                specify SMBIOS type 4 fields\n"
1875    "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n"
1876    "               [,asset=str][,part=str][,speed=%d]\n"
1877    "                specify SMBIOS type 17 fields\n",
1878    QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1879STEXI
1880@item -smbios file=@var{binary}
1881@findex -smbios
1882Load SMBIOS entry from binary file.
1883
1884@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1885Specify SMBIOS type 0 fields
1886
1887@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}]
1888Specify SMBIOS type 1 fields
1889
1890@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}]
1891Specify SMBIOS type 2 fields
1892
1893@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}]
1894Specify SMBIOS type 3 fields
1895
1896@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}]
1897Specify SMBIOS type 4 fields
1898
1899@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}]
1900Specify SMBIOS type 17 fields
1901ETEXI
1902
1903STEXI
1904@end table
1905ETEXI
1906DEFHEADING()
1907
1908DEFHEADING(Network options)
1909STEXI
1910@table @option
1911ETEXI
1912
1913HXCOMM Legacy slirp options (now moved to -net user):
1914#ifdef CONFIG_SLIRP
1915DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1916DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1917DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1918#ifndef _WIN32
1919DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1920#endif
1921#endif
1922
1923DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1924#ifdef CONFIG_SLIRP
1925    "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n"
1926    "         [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n"
1927    "         [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n"
1928    "         [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,tftp=dir]\n"
1929    "         [,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1930#ifndef _WIN32
1931                                             "[,smb=dir[,smbserver=addr]]\n"
1932#endif
1933    "                configure a user mode network backend with ID 'str',\n"
1934    "                its DHCP server and optional services\n"
1935#endif
1936#ifdef _WIN32
1937    "-netdev tap,id=str,ifname=name\n"
1938    "                configure a host TAP network backend with ID 'str'\n"
1939#else
1940    "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n"
1941    "         [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n"
1942    "         [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n"
1943    "         [,poll-us=n]\n"
1944    "                configure a host TAP network backend with ID 'str'\n"
1945    "                connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1946    "                use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1947    "                to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1948    "                to deconfigure it\n"
1949    "                use '[down]script=no' to disable script execution\n"
1950    "                use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1951    "                configure it\n"
1952    "                use 'fd=h' to connect to an already opened TAP interface\n"
1953    "                use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n"
1954    "                use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
1955    "                default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
1956    "                use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1957    "                use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1958    "                use vhost=on to enable experimental in kernel accelerator\n"
1959    "                    (only has effect for virtio guests which use MSIX)\n"
1960    "                use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1961    "                use 'vhostfd=h' to connect to an already opened vhost net device\n"
1962    "                use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n"
1963    "                use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n"
1964    "                use 'poll-us=n' to speciy the maximum number of microseconds that could be\n"
1965    "                spent on busy polling for vhost net\n"
1966    "-netdev bridge,id=str[,br=bridge][,helper=helper]\n"
1967    "                configure a host TAP network backend with ID 'str' that is\n"
1968    "                connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1969    "                using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n"
1970#endif
1971#ifdef __linux__
1972    "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n"
1973    "         [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n"
1974    "         [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n"
1975    "         [,rxcookie=rxcookie][,offset=offset]\n"
1976    "                configure a network backend with ID 'str' connected to\n"
1977    "                an Ethernet over L2TPv3 pseudowire.\n"
1978    "                Linux kernel 3.3+ as well as most routers can talk\n"
1979    "                L2TPv3. This transport allows connecting a VM to a VM,\n"
1980    "                VM to a router and even VM to Host. It is a nearly-universal\n"
1981    "                standard (RFC3391). Note - this implementation uses static\n"
1982    "                pre-configured tunnels (same as the Linux kernel).\n"
1983    "                use 'src=' to specify source address\n"
1984    "                use 'dst=' to specify destination address\n"
1985    "                use 'udp=on' to specify udp encapsulation\n"
1986    "                use 'srcport=' to specify source udp port\n"
1987    "                use 'dstport=' to specify destination udp port\n"
1988    "                use 'ipv6=on' to force v6\n"
1989    "                L2TPv3 uses cookies to prevent misconfiguration as\n"
1990    "                well as a weak security measure\n"
1991    "                use 'rxcookie=0x012345678' to specify a rxcookie\n"
1992    "                use 'txcookie=0x012345678' to specify a txcookie\n"
1993    "                use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n"
1994    "                use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n"
1995    "                use 'pincounter=on' to work around broken counter handling in peer\n"
1996    "                use 'offset=X' to add an extra offset between header and data\n"
1997#endif
1998    "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n"
1999    "                configure a network backend to connect to another network\n"
2000    "                using a socket connection\n"
2001    "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
2002    "                configure a network backend to connect to a multicast maddr and port\n"
2003    "                use 'localaddr=addr' to specify the host address to send packets from\n"
2004    "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
2005    "                configure a network backend to connect to another network\n"
2006    "                using an UDP tunnel\n"
2007#ifdef CONFIG_VDE
2008    "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
2009    "                configure a network backend to connect to port 'n' of a vde switch\n"
2010    "                running on host and listening for incoming connections on 'socketpath'.\n"
2011    "                Use group 'groupname' and mode 'octalmode' to change default\n"
2012    "                ownership and permissions for communication port.\n"
2013#endif
2014#ifdef CONFIG_NETMAP
2015    "-netdev netmap,id=str,ifname=name[,devname=nmname]\n"
2016    "                attach to the existing netmap-enabled network interface 'name', or to a\n"
2017    "                VALE port (created on the fly) called 'name' ('nmname' is name of the \n"
2018    "                netmap device, defaults to '/dev/netmap')\n"
2019#endif
2020    "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n"
2021    "                configure a vhost-user network, backed by a chardev 'dev'\n"
2022    "-netdev hubport,id=str,hubid=n\n"
2023    "                configure a hub port on QEMU VLAN 'n'\n", QEMU_ARCH_ALL)
2024DEF("net", HAS_ARG, QEMU_OPTION_net,
2025    "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
2026    "                old way to create a new NIC and connect it to VLAN 'n'\n"
2027    "                (use the '-device devtype,netdev=str' option if possible instead)\n"
2028    "-net dump[,vlan=n][,file=f][,len=n]\n"
2029    "                dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n"
2030    "-net none       use it alone to have zero network devices. If no -net option\n"
2031    "                is provided, the default is '-net nic -net user'\n"
2032    "-net ["
2033#ifdef CONFIG_SLIRP
2034    "user|"
2035#endif
2036    "tap|"
2037    "bridge|"
2038#ifdef CONFIG_VDE
2039    "vde|"
2040#endif
2041#ifdef CONFIG_NETMAP
2042    "netmap|"
2043#endif
2044    "socket][,vlan=n][,option][,option][,...]\n"
2045    "                old way to initialize a host network interface\n"
2046    "                (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL)
2047STEXI
2048@item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
2049@findex -net
2050Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
2051= 0 is the default). The NIC is an e1000 by default on the PC
2052target. Optionally, the MAC address can be changed to @var{mac}, the
2053device address set to @var{addr} (PCI cards only),
2054and a @var{name} can be assigned for use in monitor commands.
2055Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
2056that the card should have; this option currently only affects virtio cards; set
2057@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
2058NIC is created.  QEMU can emulate several different models of network card.
2059Valid values for @var{type} are
2060@code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
2061@code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
2062@code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
2063Not all devices are supported on all targets.  Use @code{-net nic,model=help}
2064for a list of available devices for your target.
2065
2066@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
2067@findex -netdev
2068@item -net user[,@var{option}][,@var{option}][,...]
2069Use the user mode network stack which requires no administrator
2070privilege to run. Valid options are:
2071
2072@table @option
2073@item vlan=@var{n}
2074Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
2075
2076@item id=@var{id}
2077@itemx name=@var{name}
2078Assign symbolic name for use in monitor commands.
2079
2080@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must
2081be enabled.  If neither is specified both protocols are enabled.
2082
2083@item net=@var{addr}[/@var{mask}]
2084Set IP network address the guest will see. Optionally specify the netmask,
2085either in the form a.b.c.d or as number of valid top-most bits. Default is
208610.0.2.0/24.
2087
2088@item host=@var{addr}
2089Specify the guest-visible address of the host. Default is the 2nd IP in the
2090guest network, i.e. x.x.x.2.
2091
2092@item ipv6-net=@var{addr}[/@var{int}]
2093Set IPv6 network address the guest will see (default is fec0::/64). The
2094network prefix is given in the usual hexadecimal IPv6 address
2095notation. The prefix size is optional, and is given as the number of
2096valid top-most bits (default is 64).
2097
2098@item ipv6-host=@var{addr}
2099Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in
2100the guest network, i.e. xxxx::2.
2101
2102@item restrict=on|off
2103If this option is enabled, the guest will be isolated, i.e. it will not be
2104able to contact the host and no guest IP packets will be routed over the host
2105to the outside. This option does not affect any explicitly set forwarding rules.
2106
2107@item hostname=@var{name}
2108Specifies the client hostname reported by the built-in DHCP server.
2109
2110@item dhcpstart=@var{addr}
2111Specify the first of the 16 IPs the built-in DHCP server can assign. Default
2112is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
2113
2114@item dns=@var{addr}
2115Specify the guest-visible address of the virtual nameserver. The address must
2116be different from the host address. Default is the 3rd IP in the guest network,
2117i.e. x.x.x.3.
2118
2119@item ipv6-dns=@var{addr}
2120Specify the guest-visible address of the IPv6 virtual nameserver. The address
2121must be different from the host address. Default is the 3rd IP in the guest
2122network, i.e. xxxx::3.
2123
2124@item dnssearch=@var{domain}
2125Provides an entry for the domain-search list sent by the built-in
2126DHCP server. More than one domain suffix can be transmitted by specifying
2127this option multiple times. If supported, this will cause the guest to
2128automatically try to append the given domain suffix(es) in case a domain name
2129can not be resolved.
2130
2131Example:
2132@example
2133qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
2134@end example
2135
2136@item tftp=@var{dir}
2137When using the user mode network stack, activate a built-in TFTP
2138server. The files in @var{dir} will be exposed as the root of a TFTP server.
2139The TFTP client on the guest must be configured in binary mode (use the command
2140@code{bin} of the Unix TFTP client).
2141
2142@item bootfile=@var{file}
2143When using the user mode network stack, broadcast @var{file} as the BOOTP
2144filename. In conjunction with @option{tftp}, this can be used to network boot
2145a guest from a local directory.
2146
2147Example (using pxelinux):
2148@example
2149qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
2150@end example
2151
2152@item smb=@var{dir}[,smbserver=@var{addr}]
2153When using the user mode network stack, activate a built-in SMB
2154server so that Windows OSes can access to the host files in @file{@var{dir}}
2155transparently. The IP address of the SMB server can be set to @var{addr}. By
2156default the 4th IP in the guest network is used, i.e. x.x.x.4.
2157
2158In the guest Windows OS, the line:
2159@example
216010.0.2.4 smbserver
2161@end example
2162must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
2163or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
2164
2165Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
2166
2167Note that a SAMBA server must be installed on the host OS.
2168QEMU was tested successfully with smbd versions from Red Hat 9,
2169Fedora Core 3 and OpenSUSE 11.x.
2170
2171@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
2172Redirect incoming TCP or UDP connections to the host port @var{hostport} to
2173the guest IP address @var{guestaddr} on guest port @var{guestport}. If
2174@var{guestaddr} is not specified, its value is x.x.x.15 (default first address
2175given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
2176be bound to a specific host interface. If no connection type is set, TCP is
2177used. This option can be given multiple times.
2178
2179For example, to redirect host X11 connection from screen 1 to guest
2180screen 0, use the following:
2181
2182@example
2183# on the host
2184qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
2185# this host xterm should open in the guest X11 server
2186xterm -display :1
2187@end example
2188
2189To redirect telnet connections from host port 5555 to telnet port on
2190the guest, use the following:
2191
2192@example
2193# on the host
2194qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
2195telnet localhost 5555
2196@end example
2197
2198Then when you use on the host @code{telnet localhost 5555}, you
2199connect to the guest telnet server.
2200
2201@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
2202@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
2203Forward guest TCP connections to the IP address @var{server} on port @var{port}
2204to the character device @var{dev} or to a program executed by @var{cmd:command}
2205which gets spawned for each connection. This option can be given multiple times.
2206
2207You can either use a chardev directly and have that one used throughout QEMU's
2208lifetime, like in the following example:
2209
2210@example
2211# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
2212# the guest accesses it
2213qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...]
2214@end example
2215
2216Or you can execute a command on every TCP connection established by the guest,
2217so that QEMU behaves similar to an inetd process for that virtual server:
2218
2219@example
2220# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
2221# and connect the TCP stream to its stdin/stdout
2222qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
2223@end example
2224
2225@end table
2226
2227Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
2228processed and applied to -net user. Mixing them with the new configuration
2229syntax gives undefined results. Their use for new applications is discouraged
2230as they will be removed from future versions.
2231
2232@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}]
2233@itemx -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}]
2234Connect the host TAP network interface @var{name} to VLAN @var{n}.
2235
2236Use the network script @var{file} to configure it and the network script
2237@var{dfile} to deconfigure it. If @var{name} is not provided, the OS
2238automatically provides one. The default network configure script is
2239@file{/etc/qemu-ifup} and the default network deconfigure script is
2240@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
2241to disable script execution.
2242
2243If running QEMU as an unprivileged user, use the network helper
2244@var{helper} to configure the TAP interface and attach it to the bridge.
2245The default network helper executable is @file{/path/to/qemu-bridge-helper}
2246and the default bridge device is @file{br0}.
2247
2248@option{fd}=@var{h} can be used to specify the handle of an already
2249opened host TAP interface.
2250
2251Examples:
2252
2253@example
2254#launch a QEMU instance with the default network script
2255qemu-system-i386 linux.img -net nic -net tap
2256@end example
2257
2258@example
2259#launch a QEMU instance with two NICs, each one connected
2260#to a TAP device
2261qemu-system-i386 linux.img \
2262                 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
2263                 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
2264@end example
2265
2266@example
2267#launch a QEMU instance with the default network helper to
2268#connect a TAP device to bridge br0
2269qemu-system-i386 linux.img \
2270                 -net nic -net tap,"helper=/path/to/qemu-bridge-helper"
2271@end example
2272
2273@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
2274@itemx -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
2275Connect a host TAP network interface to a host bridge device.
2276
2277Use the network helper @var{helper} to configure the TAP interface and
2278attach it to the bridge. The default network helper executable is
2279@file{/path/to/qemu-bridge-helper} and the default bridge
2280device is @file{br0}.
2281
2282Examples:
2283
2284@example
2285#launch a QEMU instance with the default network helper to
2286#connect a TAP device to bridge br0
2287qemu-system-i386 linux.img -net bridge -net nic,model=virtio
2288@end example
2289
2290@example
2291#launch a QEMU instance with the default network helper to
2292#connect a TAP device to bridge qemubr0
2293qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
2294@end example
2295
2296@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
2297@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
2298
2299Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
2300machine using a TCP socket connection. If @option{listen} is
2301specified, QEMU waits for incoming connections on @var{port}
2302(@var{host} is optional). @option{connect} is used to connect to
2303another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
2304specifies an already opened TCP socket.
2305
2306Example:
2307@example
2308# launch a first QEMU instance
2309qemu-system-i386 linux.img \
2310                 -net nic,macaddr=52:54:00:12:34:56 \
2311                 -net socket,listen=:1234
2312# connect the VLAN 0 of this instance to the VLAN 0
2313# of the first instance
2314qemu-system-i386 linux.img \
2315                 -net nic,macaddr=52:54:00:12:34:57 \
2316                 -net socket,connect=127.0.0.1:1234
2317@end example
2318
2319@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
2320@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
2321
2322Create a VLAN @var{n} shared with another QEMU virtual
2323machines using a UDP multicast socket, effectively making a bus for
2324every QEMU with same multicast address @var{maddr} and @var{port}.
2325NOTES:
2326@enumerate
2327@item
2328Several QEMU can be running on different hosts and share same bus (assuming
2329correct multicast setup for these hosts).
2330@item
2331mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
2332@url{http://user-mode-linux.sf.net}.
2333@item
2334Use @option{fd=h} to specify an already opened UDP multicast socket.
2335@end enumerate
2336
2337Example:
2338@example
2339# launch one QEMU instance
2340qemu-system-i386 linux.img \
2341                 -net nic,macaddr=52:54:00:12:34:56 \
2342                 -net socket,mcast=230.0.0.1:1234
2343# launch another QEMU instance on same "bus"
2344qemu-system-i386 linux.img \
2345                 -net nic,macaddr=52:54:00:12:34:57 \
2346                 -net socket,mcast=230.0.0.1:1234
2347# launch yet another QEMU instance on same "bus"
2348qemu-system-i386 linux.img \
2349                 -net nic,macaddr=52:54:00:12:34:58 \
2350                 -net socket,mcast=230.0.0.1:1234
2351@end example
2352
2353Example (User Mode Linux compat.):
2354@example
2355# launch QEMU instance (note mcast address selected
2356# is UML's default)
2357qemu-system-i386 linux.img \
2358                 -net nic,macaddr=52:54:00:12:34:56 \
2359                 -net socket,mcast=239.192.168.1:1102
2360# launch UML
2361/path/to/linux ubd0=/path/to/root_fs eth0=mcast
2362@end example
2363
2364Example (send packets from host's 1.2.3.4):
2365@example
2366qemu-system-i386 linux.img \
2367                 -net nic,macaddr=52:54:00:12:34:56 \
2368                 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
2369@end example
2370
2371@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}]
2372@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}]
2373Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular
2374protocol to transport Ethernet (and other Layer 2) data frames between
2375two systems. It is present in routers, firewalls and the Linux kernel
2376(from version 3.3 onwards).
2377
2378This transport allows a VM to communicate to another VM, router or firewall directly.
2379
2380@item src=@var{srcaddr}
2381    source address (mandatory)
2382@item dst=@var{dstaddr}
2383    destination address (mandatory)
2384@item udp
2385    select udp encapsulation (default is ip).
2386@item srcport=@var{srcport}
2387    source udp port.
2388@item dstport=@var{dstport}
2389    destination udp port.
2390@item ipv6
2391    force v6, otherwise defaults to v4.
2392@item rxcookie=@var{rxcookie}
2393@itemx txcookie=@var{txcookie}
2394    Cookies are a weak form of security in the l2tpv3 specification.
2395Their function is mostly to prevent misconfiguration. By default they are 32
2396bit.
2397@item cookie64
2398    Set cookie size to 64 bit instead of the default 32
2399@item counter=off
2400    Force a 'cut-down' L2TPv3 with no counter as in
2401draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00
2402@item pincounter=on
2403    Work around broken counter handling in peer. This may also help on
2404networks which have packet reorder.
2405@item offset=@var{offset}
2406    Add an extra offset between header and data
2407
2408For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan
2409on the remote Linux host 1.2.3.4:
2410@example
2411# Setup tunnel on linux host using raw ip as encapsulation
2412# on 1.2.3.4
2413ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \
2414    encap udp udp_sport 16384 udp_dport 16384
2415ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \
2416    0xFFFFFFFF peer_session_id 0xFFFFFFFF
2417ifconfig vmtunnel0 mtu 1500
2418ifconfig vmtunnel0 up
2419brctl addif br-lan vmtunnel0
2420
2421
2422# on 4.3.2.1
2423# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter
2424
2425qemu-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
2426
2427
2428@end example
2429
2430@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2431@itemx -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2432Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
2433listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
2434and MODE @var{octalmode} to change default ownership and permissions for
2435communication port. This option is only available if QEMU has been compiled
2436with vde support enabled.
2437
2438Example:
2439@example
2440# launch vde switch
2441vde_switch -F -sock /tmp/myswitch
2442# launch QEMU instance
2443qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch
2444@end example
2445
2446@item -netdev hubport,id=@var{id},hubid=@var{hubid}
2447
2448Create a hub port on QEMU "vlan" @var{hubid}.
2449
2450The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single
2451netdev.  @code{-net} and @code{-device} with parameter @option{vlan} create the
2452required hub automatically.
2453
2454@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n]
2455
2456Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should
2457be a unix domain socket backed one. The vhost-user uses a specifically defined
2458protocol to pass vhost ioctl replacement messages to an application on the other
2459end of the socket. On non-MSIX guests, the feature can be forced with
2460@var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to
2461be created for multiqueue vhost-user.
2462
2463Example:
2464@example
2465qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \
2466     -numa node,memdev=mem \
2467     -chardev socket,id=chr0,path=/path/to/socket \
2468     -netdev type=vhost-user,id=net0,chardev=chr0 \
2469     -device virtio-net-pci,netdev=net0
2470@end example
2471
2472@item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
2473Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
2474At most @var{len} bytes (64k by default) per packet are stored. The file format is
2475libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
2476Note: For devices created with '-netdev', use '-object filter-dump,...' instead.
2477
2478@item -net none
2479Indicate that no network devices should be configured. It is used to
2480override the default configuration (@option{-net nic -net user}) which
2481is activated if no @option{-net} options are provided.
2482ETEXI
2483
2484STEXI
2485@end table
2486ETEXI
2487DEFHEADING()
2488
2489DEFHEADING(Character device options)
2490STEXI
2491
2492The general form of a character device option is:
2493@table @option
2494ETEXI
2495
2496DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
2497    "-chardev help\n"
2498    "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2499    "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
2500    "         [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n"
2501    "         [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n"
2502    "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n"
2503    "         [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n"
2504    "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
2505    "         [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
2506    "         [,logfile=PATH][,logappend=on|off]\n"
2507    "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2508    "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
2509    "         [,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2510    "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n"
2511    "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2512    "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2513#ifdef _WIN32
2514    "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2515    "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2516#else
2517    "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2518    "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n"
2519#endif
2520#ifdef CONFIG_BRLAPI
2521    "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2522#endif
2523#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
2524        || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
2525    "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2526    "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2527#endif
2528#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
2529    "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2530    "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2531#endif
2532#if defined(CONFIG_SPICE)
2533    "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2534    "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2535#endif
2536    , QEMU_ARCH_ALL
2537)
2538
2539STEXI
2540@item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
2541@findex -chardev
2542Backend is one of:
2543@option{null},
2544@option{socket},
2545@option{udp},
2546@option{msmouse},
2547@option{vc},
2548@option{ringbuf},
2549@option{file},
2550@option{pipe},
2551@option{console},
2552@option{serial},
2553@option{pty},
2554@option{stdio},
2555@option{braille},
2556@option{tty},
2557@option{parallel},
2558@option{parport},
2559@option{spicevmc}.
2560@option{spiceport}.
2561The specific backend will determine the applicable options.
2562
2563Use "-chardev help" to print all available chardev backend types.
2564
2565All devices must have an id, which can be any string up to 127 characters long.
2566It is used to uniquely identify this device in other command line directives.
2567
2568A character device may be used in multiplexing mode by multiple front-ends.
2569Specify @option{mux=on} to enable this mode.
2570A multiplexer is a "1:N" device, and here the "1" end is your specified chardev
2571backend, and the "N" end is the various parts of QEMU that can talk to a chardev.
2572If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will
2573create a multiplexer with your specified ID, and you can then configure multiple
2574front ends to use that chardev ID for their input/output. Up to four different
2575front ends can be connected to a single multiplexed chardev. (Without
2576multiplexing enabled, a chardev can only be used by a single front end.)
2577For instance you could use this to allow a single stdio chardev to be used by
2578two serial ports and the QEMU monitor:
2579
2580@example
2581-chardev stdio,mux=on,id=char0 \
2582-mon chardev=char0,mode=readline \
2583-serial chardev:char0 \
2584-serial chardev:char0
2585@end example
2586
2587You can have more than one multiplexer in a system configuration; for instance
2588you could have a TCP port multiplexed between UART 0 and UART 1, and stdio
2589multiplexed between the QEMU monitor and a parallel port:
2590
2591@example
2592-chardev stdio,mux=on,id=char0 \
2593-mon chardev=char0,mode=readline \
2594-parallel chardev:char0 \
2595-chardev tcp,...,mux=on,id=char1 \
2596-serial chardev:char1 \
2597-serial chardev:char1
2598@end example
2599
2600When you're using a multiplexed character device, some escape sequences are
2601interpreted in the input. @xref{mux_keys, Keys in the character backend
2602multiplexer}.
2603
2604Note that some other command line options may implicitly create multiplexed
2605character backends; for instance @option{-serial mon:stdio} creates a
2606multiplexed stdio backend connected to the serial port and the QEMU monitor,
2607and @option{-nographic} also multiplexes the console and the monitor to
2608stdio.
2609
2610There is currently no support for multiplexing in the other direction
2611(where a single QEMU front end takes input and output from multiple chardevs).
2612
2613Every backend supports the @option{logfile} option, which supplies the path
2614to a file to record all data transmitted via the backend. The @option{logappend}
2615option controls whether the log file will be truncated or appended to when
2616opened.
2617
2618Further options to each backend are described below.
2619
2620@item -chardev null ,id=@var{id}
2621A void device. This device will not emit any data, and will drop any data it
2622receives. The null backend does not take any options.
2623
2624@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}] [,tls-creds=@var{id}]
2625
2626Create a two-way stream socket, which can be either a TCP or a unix socket. A
2627unix socket will be created if @option{path} is specified. Behaviour is
2628undefined if TCP options are specified for a unix socket.
2629
2630@option{server} specifies that the socket shall be a listening socket.
2631
2632@option{nowait} specifies that QEMU should not block waiting for a client to
2633connect to a listening socket.
2634
2635@option{telnet} specifies that traffic on the socket should interpret telnet
2636escape sequences.
2637
2638@option{reconnect} sets the timeout for reconnecting on non-server sockets when
2639the remote end goes away.  qemu will delay this many seconds and then attempt
2640to reconnect.  Zero disables reconnecting, and is the default.
2641
2642@option{tls-creds} requests enablement of the TLS protocol for encryption,
2643and specifies the id of the TLS credentials to use for the handshake. The
2644credentials must be previously created with the @option{-object tls-creds}
2645argument.
2646
2647TCP and unix socket options are given below:
2648
2649@table @option
2650
2651@item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
2652
2653@option{host} for a listening socket specifies the local address to be bound.
2654For a connecting socket species the remote host to connect to. @option{host} is
2655optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
2656
2657@option{port} for a listening socket specifies the local port to be bound. For a
2658connecting socket specifies the port on the remote host to connect to.
2659@option{port} can be given as either a port number or a service name.
2660@option{port} is required.
2661
2662@option{to} is only relevant to listening sockets. If it is specified, and
2663@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
2664to and including @option{to} until it succeeds. @option{to} must be specified
2665as a port number.
2666
2667@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2668If neither is specified the socket may use either protocol.
2669
2670@option{nodelay} disables the Nagle algorithm.
2671
2672@item unix options: path=@var{path}
2673
2674@option{path} specifies the local path of the unix socket. @option{path} is
2675required.
2676
2677@end table
2678
2679@item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
2680
2681Sends all traffic from the guest to a remote host over UDP.
2682
2683@option{host} specifies the remote host to connect to. If not specified it
2684defaults to @code{localhost}.
2685
2686@option{port} specifies the port on the remote host to connect to. @option{port}
2687is required.
2688
2689@option{localaddr} specifies the local address to bind to. If not specified it
2690defaults to @code{0.0.0.0}.
2691
2692@option{localport} specifies the local port to bind to. If not specified any
2693available local port will be used.
2694
2695@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2696If neither is specified the device may use either protocol.
2697
2698@item -chardev msmouse ,id=@var{id}
2699
2700Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
2701take any options.
2702
2703@item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
2704
2705Connect to a QEMU text console. @option{vc} may optionally be given a specific
2706size.
2707
2708@option{width} and @option{height} specify the width and height respectively of
2709the console, in pixels.
2710
2711@option{cols} and @option{rows} specify that the console be sized to fit a text
2712console with the given dimensions.
2713
2714@item -chardev ringbuf ,id=@var{id} [,size=@var{size}]
2715
2716Create a ring buffer with fixed size @option{size}.
2717@var{size} must be a power of two and defaults to @code{64K}.
2718
2719@item -chardev file ,id=@var{id} ,path=@var{path}
2720
2721Log all traffic received from the guest to a file.
2722
2723@option{path} specifies the path of the file to be opened. This file will be
2724created if it does not already exist, and overwritten if it does. @option{path}
2725is required.
2726
2727@item -chardev pipe ,id=@var{id} ,path=@var{path}
2728
2729Create a two-way connection to the guest. The behaviour differs slightly between
2730Windows hosts and other hosts:
2731
2732On Windows, a single duplex pipe will be created at
2733@file{\\.pipe\@option{path}}.
2734
2735On other hosts, 2 pipes will be created called @file{@option{path}.in} and
2736@file{@option{path}.out}. Data written to @file{@option{path}.in} will be
2737received by the guest. Data written by the guest can be read from
2738@file{@option{path}.out}. QEMU will not create these fifos, and requires them to
2739be present.
2740
2741@option{path} forms part of the pipe path as described above. @option{path} is
2742required.
2743
2744@item -chardev console ,id=@var{id}
2745
2746Send traffic from the guest to QEMU's standard output. @option{console} does not
2747take any options.
2748
2749@option{console} is only available on Windows hosts.
2750
2751@item -chardev serial ,id=@var{id} ,path=@option{path}
2752
2753Send traffic from the guest to a serial device on the host.
2754
2755On Unix hosts serial will actually accept any tty device,
2756not only serial lines.
2757
2758@option{path} specifies the name of the serial device to open.
2759
2760@item -chardev pty ,id=@var{id}
2761
2762Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2763not take any options.
2764
2765@option{pty} is not available on Windows hosts.
2766
2767@item -chardev stdio ,id=@var{id} [,signal=on|off]
2768Connect to standard input and standard output of the QEMU process.
2769
2770@option{signal} controls if signals are enabled on the terminal, that includes
2771exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2772default, use @option{signal=off} to disable it.
2773
2774@item -chardev braille ,id=@var{id}
2775
2776Connect to a local BrlAPI server. @option{braille} does not take any options.
2777
2778@item -chardev tty ,id=@var{id} ,path=@var{path}
2779
2780@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2781DragonFlyBSD hosts.  It is an alias for @option{serial}.
2782
2783@option{path} specifies the path to the tty. @option{path} is required.
2784
2785@item -chardev parallel ,id=@var{id} ,path=@var{path}
2786@itemx -chardev parport ,id=@var{id} ,path=@var{path}
2787
2788@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2789
2790Connect to a local parallel port.
2791
2792@option{path} specifies the path to the parallel port device. @option{path} is
2793required.
2794
2795@item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2796
2797@option{spicevmc} is only available when spice support is built in.
2798
2799@option{debug} debug level for spicevmc
2800
2801@option{name} name of spice channel to connect to
2802
2803Connect to a spice virtual machine channel, such as vdiport.
2804
2805@item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2806
2807@option{spiceport} is only available when spice support is built in.
2808
2809@option{debug} debug level for spicevmc
2810
2811@option{name} name of spice port to connect to
2812
2813Connect to a spice port, allowing a Spice client to handle the traffic
2814identified by a name (preferably a fqdn).
2815ETEXI
2816
2817STEXI
2818@end table
2819ETEXI
2820DEFHEADING()
2821
2822DEFHEADING(Device URL Syntax)
2823STEXI
2824
2825In addition to using normal file images for the emulated storage devices,
2826QEMU can also use networked resources such as iSCSI devices. These are
2827specified using a special URL syntax.
2828
2829@table @option
2830@item iSCSI
2831iSCSI support allows QEMU to access iSCSI resources directly and use as
2832images for the guest storage. Both disk and cdrom images are supported.
2833
2834Syntax for specifying iSCSI LUNs is
2835``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
2836
2837By default qemu will use the iSCSI initiator-name
2838'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command
2839line or a configuration file.
2840
2841Since version Qemu 2.4 it is possible to specify a iSCSI request timeout to detect
2842stalled requests and force a reestablishment of the session. The timeout
2843is specified in seconds. The default is 0 which means no timeout. Libiscsi
28441.15.0 or greater is required for this feature.
2845
2846Example (without authentication):
2847@example
2848qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
2849                 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
2850                 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2851@end example
2852
2853Example (CHAP username/password via URL):
2854@example
2855qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
2856@end example
2857
2858Example (CHAP username/password via environment variables):
2859@example
2860LIBISCSI_CHAP_USERNAME="user" \
2861LIBISCSI_CHAP_PASSWORD="password" \
2862qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2863@end example
2864
2865iSCSI support is an optional feature of QEMU and only available when
2866compiled and linked against libiscsi.
2867ETEXI
2868DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
2869    "-iscsi [user=user][,password=password]\n"
2870    "       [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
2871    "       [,initiator-name=initiator-iqn][,id=target-iqn]\n"
2872    "       [,timeout=timeout]\n"
2873    "                iSCSI session parameters\n", QEMU_ARCH_ALL)
2874STEXI
2875
2876iSCSI parameters such as username and password can also be specified via
2877a configuration file. See qemu-doc for more information and examples.
2878
2879@item NBD
2880QEMU supports NBD (Network Block Devices) both using TCP protocol as well
2881as Unix Domain Sockets.
2882
2883Syntax for specifying a NBD device using TCP
2884``nbd:<server-ip>:<port>[:exportname=<export>]''
2885
2886Syntax for specifying a NBD device using Unix Domain Sockets
2887``nbd:unix:<domain-socket>[:exportname=<export>]''
2888
2889
2890Example for TCP
2891@example
2892qemu-system-i386 --drive file=nbd:192.0.2.1:30000
2893@end example
2894
2895Example for Unix Domain Sockets
2896@example
2897qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket
2898@end example
2899
2900@item SSH
2901QEMU supports SSH (Secure Shell) access to remote disks.
2902
2903Examples:
2904@example
2905qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img
2906qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img
2907@end example
2908
2909Currently authentication must be done using ssh-agent.  Other
2910authentication methods may be supported in future.
2911
2912@item Sheepdog
2913Sheepdog is a distributed storage system for QEMU.
2914QEMU supports using either local sheepdog devices or remote networked
2915devices.
2916
2917Syntax for specifying a sheepdog device
2918@example
2919sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag]
2920@end example
2921
2922Example
2923@example
2924qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine
2925@end example
2926
2927See also @url{https://sheepdog.github.io/sheepdog/}.
2928
2929@item GlusterFS
2930GlusterFS is a user space distributed file system.
2931QEMU supports the use of GlusterFS volumes for hosting VM disk images using
2932TCP, Unix Domain Sockets and RDMA transport protocols.
2933
2934Syntax for specifying a VM disk image on GlusterFS volume is
2935@example
2936
2937URI:
2938gluster[+type]://[host[:port]]/volume/path[?socket=...][,debug=N][,logfile=...]
2939
2940JSON:
2941'json:@{"driver":"qcow2","file":@{"driver":"gluster","volume":"testvol","path":"a.img","debug":N,"logfile":"...",
2942@                                 "server":[@{"type":"tcp","host":"...","port":"..."@},
2943@                                           @{"type":"unix","socket":"..."@}]@}@}'
2944@end example
2945
2946
2947Example
2948@example
2949URI:
2950qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img,
2951@                               file.debug=9,file.logfile=/var/log/qemu-gluster.log
2952
2953JSON:
2954qemu-system-x86_64 'json:@{"driver":"qcow2",
2955@                          "file":@{"driver":"gluster",
2956@                                   "volume":"testvol","path":"a.img",
2957@                                   "debug":9,"logfile":"/var/log/qemu-gluster.log",
2958@                                   "server":[@{"type":"tcp","host":"1.2.3.4","port":24007@},
2959@                                             @{"type":"unix","socket":"/var/run/glusterd.socket"@}]@}@}'
2960qemu-system-x86_64 -drive driver=qcow2,file.driver=gluster,file.volume=testvol,file.path=/path/a.img,
2961@                                      file.debug=9,file.logfile=/var/log/qemu-gluster.log,
2962@                                      file.server.0.type=tcp,file.server.0.host=1.2.3.4,file.server.0.port=24007,
2963@                                      file.server.1.type=unix,file.server.1.socket=/var/run/glusterd.socket
2964@end example
2965
2966See also @url{http://www.gluster.org}.
2967
2968@item HTTP/HTTPS/FTP/FTPS
2969QEMU supports read-only access to files accessed over http(s) and ftp(s).
2970
2971Syntax using a single filename:
2972@example
2973<protocol>://[<username>[:<password>]@@]<host>/<path>
2974@end example
2975
2976where:
2977@table @option
2978@item protocol
2979'http', 'https', 'ftp', or 'ftps'.
2980
2981@item username
2982Optional username for authentication to the remote server.
2983
2984@item password
2985Optional password for authentication to the remote server.
2986
2987@item host
2988Address of the remote server.
2989
2990@item path
2991Path on the remote server, including any query string.
2992@end table
2993
2994The following options are also supported:
2995@table @option
2996@item url
2997The full URL when passing options to the driver explicitly.
2998
2999@item readahead
3000The amount of data to read ahead with each range request to the remote server.
3001This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it
3002does not have a suffix, it will be assumed to be in bytes. The value must be a
3003multiple of 512 bytes. It defaults to 256k.
3004
3005@item sslverify
3006Whether to verify the remote server's certificate when connecting over SSL. It
3007can have the value 'on' or 'off'. It defaults to 'on'.
3008
3009@item cookie
3010Send this cookie (it can also be a list of cookies separated by ';') with
3011each outgoing request.  Only supported when using protocols such as HTTP
3012which support cookies, otherwise ignored.
3013
3014@item timeout
3015Set the timeout in seconds of the CURL connection. This timeout is the time
3016that CURL waits for a response from the remote server to get the size of the
3017image to be downloaded. If not set, the default timeout of 5 seconds is used.
3018@end table
3019
3020Note that when passing options to qemu explicitly, @option{driver} is the value
3021of <protocol>.
3022
3023Example: boot from a remote Fedora 20 live ISO image
3024@example
3025qemu-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
3026
3027qemu-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
3028@end example
3029
3030Example: boot from a remote Fedora 20 cloud image using a local overlay for
3031writes, copy-on-read, and a readahead of 64k
3032@example
3033qemu-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
3034
3035qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on
3036@end example
3037
3038Example: boot from an image stored on a VMware vSphere server with a self-signed
3039certificate using a local overlay for writes, a readahead of 64k and a timeout
3040of 10 seconds.
3041@example
3042qemu-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
3043
3044qemu-system-x86_64 -drive file=/tmp/test.qcow2
3045@end example
3046ETEXI
3047
3048STEXI
3049@end table
3050ETEXI
3051
3052DEFHEADING(Bluetooth(R) options)
3053STEXI
3054@table @option
3055ETEXI
3056
3057DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
3058    "-bt hci,null    dumb bluetooth HCI - doesn't respond to commands\n" \
3059    "-bt hci,host[:id]\n" \
3060    "                use host's HCI with the given name\n" \
3061    "-bt hci[,vlan=n]\n" \
3062    "                emulate a standard HCI in virtual scatternet 'n'\n" \
3063    "-bt vhci[,vlan=n]\n" \
3064    "                add host computer to virtual scatternet 'n' using VHCI\n" \
3065    "-bt device:dev[,vlan=n]\n" \
3066    "                emulate a bluetooth device 'dev' in scatternet 'n'\n",
3067    QEMU_ARCH_ALL)
3068STEXI
3069@item -bt hci[...]
3070@findex -bt
3071Defines the function of the corresponding Bluetooth HCI.  -bt options
3072are matched with the HCIs present in the chosen machine type.  For
3073example when emulating a machine with only one HCI built into it, only
3074the first @code{-bt hci[...]} option is valid and defines the HCI's
3075logic.  The Transport Layer is decided by the machine type.  Currently
3076the machines @code{n800} and @code{n810} have one HCI and all other
3077machines have none.
3078
3079@anchor{bt-hcis}
3080The following three types are recognized:
3081
3082@table @option
3083@item -bt hci,null
3084(default) The corresponding Bluetooth HCI assumes no internal logic
3085and will not respond to any HCI commands or emit events.
3086
3087@item -bt hci,host[:@var{id}]
3088(@code{bluez} only) The corresponding HCI passes commands / events
3089to / from the physical HCI identified by the name @var{id} (default:
3090@code{hci0}) on the computer running QEMU.  Only available on @code{bluez}
3091capable systems like Linux.
3092
3093@item -bt hci[,vlan=@var{n}]
3094Add a virtual, standard HCI that will participate in the Bluetooth
3095scatternet @var{n} (default @code{0}).  Similarly to @option{-net}
3096VLANs, devices inside a bluetooth network @var{n} can only communicate
3097with other devices in the same network (scatternet).
3098@end table
3099
3100@item -bt vhci[,vlan=@var{n}]
3101(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
3102to the host bluetooth stack instead of to the emulated target.  This
3103allows the host and target machines to participate in a common scatternet
3104and communicate.  Requires the Linux @code{vhci} driver installed.  Can
3105be used as following:
3106
3107@example
3108qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
3109@end example
3110
3111@item -bt device:@var{dev}[,vlan=@var{n}]
3112Emulate a bluetooth device @var{dev} and place it in network @var{n}
3113(default @code{0}).  QEMU can only emulate one type of bluetooth devices
3114currently:
3115
3116@table @option
3117@item keyboard
3118Virtual wireless keyboard implementing the HIDP bluetooth profile.
3119@end table
3120ETEXI
3121
3122STEXI
3123@end table
3124ETEXI
3125DEFHEADING()
3126
3127#ifdef CONFIG_TPM
3128DEFHEADING(TPM device options)
3129
3130DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
3131    "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
3132    "                use path to provide path to a character device; default is /dev/tpm0\n"
3133    "                use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
3134    "                not provided it will be searched for in /sys/class/misc/tpm?/device\n"
3135    "-tpmdev emulator,id=id,chardev=dev\n"
3136    "                configure the TPM device using chardev backend\n",
3137    QEMU_ARCH_ALL)
3138STEXI
3139
3140The general form of a TPM device option is:
3141@table @option
3142
3143@item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
3144@findex -tpmdev
3145Backend type must be either one of the following:
3146@option{passthrough}, @option{emulator}.
3147
3148The specific backend type will determine the applicable options.
3149The @code{-tpmdev} option creates the TPM backend and requires a
3150@code{-device} option that specifies the TPM frontend interface model.
3151
3152Options to each backend are described below.
3153
3154Use 'help' to print all available TPM backend types.
3155@example
3156qemu -tpmdev help
3157@end example
3158
3159@item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path}
3160
3161(Linux-host only) Enable access to the host's TPM using the passthrough
3162driver.
3163
3164@option{path} specifies the path to the host's TPM device, i.e., on
3165a Linux host this would be @code{/dev/tpm0}.
3166@option{path} is optional and by default @code{/dev/tpm0} is used.
3167
3168@option{cancel-path} specifies the path to the host TPM device's sysfs
3169entry allowing for cancellation of an ongoing TPM command.
3170@option{cancel-path} is optional and by default QEMU will search for the
3171sysfs entry to use.
3172
3173Some notes about using the host's TPM with the passthrough driver:
3174
3175The TPM device accessed by the passthrough driver must not be
3176used by any other application on the host.
3177
3178Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
3179the VM's firmware (BIOS/UEFI) will not be able to initialize the
3180TPM again and may therefore not show a TPM-specific menu that would
3181otherwise allow the user to configure the TPM, e.g., allow the user to
3182enable/disable or activate/deactivate the TPM.
3183Further, if TPM ownership is released from within a VM then the host's TPM
3184will get disabled and deactivated. To enable and activate the
3185TPM again afterwards, the host has to be rebooted and the user is
3186required to enter the firmware's menu to enable and activate the TPM.
3187If the TPM is left disabled and/or deactivated most TPM commands will fail.
3188
3189To create a passthrough TPM use the following two options:
3190@example
3191-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
3192@end example
3193Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
3194@code{tpmdev=tpm0} in the device option.
3195
3196@item -tpmdev emulator, id=@var{id}, chardev=@var{dev}
3197
3198(Linux-host only) Enable access to a TPM emulator using Unix domain socket based
3199chardev backend.
3200
3201@option{chardev} specifies the unique ID of a character device backend that provides connection to the software TPM server.
3202
3203To create a TPM emulator backend device with chardev socket backend:
3204@example
3205
3206-chardev socket,id=chrtpm,path=/tmp/swtpm-sock -tpmdev emulator,id=tpm0,chardev=chrtpm -device tpm-tis,tpmdev=tpm0
3207
3208@end example
3209
3210@end table
3211
3212ETEXI
3213
3214DEFHEADING()
3215
3216#endif
3217
3218DEFHEADING(Linux/Multiboot boot specific)
3219STEXI
3220
3221When using these options, you can use a given Linux or Multiboot
3222kernel without installing it in the disk image. It can be useful
3223for easier testing of various kernels.
3224
3225@table @option
3226ETEXI
3227
3228DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
3229    "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL)
3230STEXI
3231@item -kernel @var{bzImage}
3232@findex -kernel
3233Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
3234or in multiboot format.
3235ETEXI
3236
3237DEF("append", HAS_ARG, QEMU_OPTION_append, \
3238    "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL)
3239STEXI
3240@item -append @var{cmdline}
3241@findex -append
3242Use @var{cmdline} as kernel command line
3243ETEXI
3244
3245DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
3246           "-initrd file    use 'file' as initial ram disk\n", QEMU_ARCH_ALL)
3247STEXI
3248@item -initrd @var{file}
3249@findex -initrd
3250Use @var{file} as initial ram disk.
3251
3252@item -initrd "@var{file1} arg=foo,@var{file2}"
3253
3254This syntax is only available with multiboot.
3255
3256Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
3257first module.
3258ETEXI
3259
3260DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
3261    "-dtb    file    use 'file' as device tree image\n", QEMU_ARCH_ALL)
3262STEXI
3263@item -dtb @var{file}
3264@findex -dtb
3265Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
3266on boot.
3267ETEXI
3268
3269STEXI
3270@end table
3271ETEXI
3272DEFHEADING()
3273
3274DEFHEADING(Debug/Expert options)
3275STEXI
3276@table @option
3277ETEXI
3278
3279DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg,
3280    "-fw_cfg [name=]<name>,file=<file>\n"
3281    "                add named fw_cfg entry with contents from file\n"
3282    "-fw_cfg [name=]<name>,string=<str>\n"
3283    "                add named fw_cfg entry with contents from string\n",
3284    QEMU_ARCH_ALL)
3285STEXI
3286
3287@item -fw_cfg [name=]@var{name},file=@var{file}
3288@findex -fw_cfg
3289Add named fw_cfg entry with contents from file @var{file}.
3290
3291@item -fw_cfg [name=]@var{name},string=@var{str}
3292Add named fw_cfg entry with contents from string @var{str}.
3293
3294The terminating NUL character of the contents of @var{str} will not be
3295included as part of the fw_cfg item data. To insert contents with
3296embedded NUL characters, you have to use the @var{file} parameter.
3297
3298The fw_cfg entries are passed by QEMU through to the guest.
3299
3300Example:
3301@example
3302    -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin
3303@end example
3304creates an fw_cfg entry named opt/com.mycompany/blob with contents
3305from ./my_blob.bin.
3306
3307ETEXI
3308
3309DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
3310    "-serial dev     redirect the serial port to char device 'dev'\n",
3311    QEMU_ARCH_ALL)
3312STEXI
3313@item -serial @var{dev}
3314@findex -serial
3315Redirect the virtual serial port to host character device
3316@var{dev}. The default device is @code{vc} in graphical mode and
3317@code{stdio} in non graphical mode.
3318
3319This option can be used several times to simulate up to 4 serial
3320ports.
3321
3322Use @code{-serial none} to disable all serial ports.
3323
3324Available character devices are:
3325@table @option
3326@item vc[:@var{W}x@var{H}]
3327Virtual console. Optionally, a width and height can be given in pixel with
3328@example
3329vc:800x600
3330@end example
3331It is also possible to specify width or height in characters:
3332@example
3333vc:80Cx24C
3334@end example
3335@item pty
3336[Linux only] Pseudo TTY (a new PTY is automatically allocated)
3337@item none
3338No device is allocated.
3339@item null
3340void device
3341@item chardev:@var{id}
3342Use a named character device defined with the @code{-chardev} option.
3343@item /dev/XXX
3344[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
3345parameters are set according to the emulated ones.
3346@item /dev/parport@var{N}
3347[Linux only, parallel port only] Use host parallel port
3348@var{N}. Currently SPP and EPP parallel port features can be used.
3349@item file:@var{filename}
3350Write output to @var{filename}. No character can be read.
3351@item stdio
3352[Unix only] standard input/output
3353@item pipe:@var{filename}
3354name pipe @var{filename}
3355@item COM@var{n}
3356[Windows only] Use host serial port @var{n}
3357@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
3358This implements UDP Net Console.
3359When @var{remote_host} or @var{src_ip} are not specified
3360they default to @code{0.0.0.0}.
3361When not using a specified @var{src_port} a random port is automatically chosen.
3362
3363If you just want a simple readonly console you can use @code{netcat} or
3364@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
3365@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
3366will appear in the netconsole session.
3367
3368If you plan to send characters back via netconsole or you want to stop
3369and start QEMU a lot of times, you should have QEMU use the same
3370source port each time by using something like @code{-serial
3371udp::4555@@:4556} to QEMU. Another approach is to use a patched
3372version of netcat which can listen to a TCP port and send and receive
3373characters via udp.  If you have a patched version of netcat which
3374activates telnet remote echo and single char transfer, then you can
3375use the following options to set up a netcat redirector to allow
3376telnet on port 5555 to access the QEMU port.
3377@table @code
3378@item QEMU Options:
3379-serial udp::4555@@:4556
3380@item netcat options:
3381-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
3382@item telnet options:
3383localhost 5555
3384@end table
3385
3386@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}]
3387The TCP Net Console has two modes of operation.  It can send the serial
3388I/O to a location or wait for a connection from a location.  By default
3389the TCP Net Console is sent to @var{host} at the @var{port}.  If you use
3390the @var{server} option QEMU will wait for a client socket application
3391to connect to the port before continuing, unless the @code{nowait}
3392option was specified.  The @code{nodelay} option disables the Nagle buffering
3393algorithm.  The @code{reconnect} option only applies if @var{noserver} is
3394set, if the connection goes down it will attempt to reconnect at the
3395given interval.  If @var{host} is omitted, 0.0.0.0 is assumed. Only
3396one TCP connection at a time is accepted. You can use @code{telnet} to
3397connect to the corresponding character device.
3398@table @code
3399@item Example to send tcp console to 192.168.0.2 port 4444
3400-serial tcp:192.168.0.2:4444
3401@item Example to listen and wait on port 4444 for connection
3402-serial tcp::4444,server
3403@item Example to not wait and listen on ip 192.168.0.100 port 4444
3404-serial tcp:192.168.0.100:4444,server,nowait
3405@end table
3406
3407@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
3408The telnet protocol is used instead of raw tcp sockets.  The options
3409work the same as if you had specified @code{-serial tcp}.  The
3410difference is that the port acts like a telnet server or client using
3411telnet option negotiation.  This will also allow you to send the
3412MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
3413sequence.  Typically in unix telnet you do it with Control-] and then
3414type "send break" followed by pressing the enter key.
3415
3416@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}]
3417A unix domain socket is used instead of a tcp socket.  The option works the
3418same as if you had specified @code{-serial tcp} except the unix domain socket
3419@var{path} is used for connections.
3420
3421@item mon:@var{dev_string}
3422This is a special option to allow the monitor to be multiplexed onto
3423another serial port.  The monitor is accessed with key sequence of
3424@key{Control-a} and then pressing @key{c}.
3425@var{dev_string} should be any one of the serial devices specified
3426above.  An example to multiplex the monitor onto a telnet server
3427listening on port 4444 would be:
3428@table @code
3429@item -serial mon:telnet::4444,server,nowait
3430@end table
3431When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
3432QEMU any more but will be passed to the guest instead.
3433
3434@item braille
3435Braille device.  This will use BrlAPI to display the braille output on a real
3436or fake device.
3437
3438@item msmouse
3439Three button serial mouse. Configure the guest to use Microsoft protocol.
3440@end table
3441ETEXI
3442
3443DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
3444    "-parallel dev   redirect the parallel port to char device 'dev'\n",
3445    QEMU_ARCH_ALL)
3446STEXI
3447@item -parallel @var{dev}
3448@findex -parallel
3449Redirect the virtual parallel port to host device @var{dev} (same
3450devices as the serial port). On Linux hosts, @file{/dev/parportN} can
3451be used to use hardware devices connected on the corresponding host
3452parallel port.
3453
3454This option can be used several times to simulate up to 3 parallel
3455ports.
3456
3457Use @code{-parallel none} to disable all parallel ports.
3458ETEXI
3459
3460DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
3461    "-monitor dev    redirect the monitor to char device 'dev'\n",
3462    QEMU_ARCH_ALL)
3463STEXI
3464@item -monitor @var{dev}
3465@findex -monitor
3466Redirect the monitor to host device @var{dev} (same devices as the
3467serial port).
3468The default device is @code{vc} in graphical mode and @code{stdio} in
3469non graphical mode.
3470Use @code{-monitor none} to disable the default monitor.
3471ETEXI
3472DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
3473    "-qmp dev        like -monitor but opens in 'control' mode\n",
3474    QEMU_ARCH_ALL)
3475STEXI
3476@item -qmp @var{dev}
3477@findex -qmp
3478Like -monitor but opens in 'control' mode.
3479ETEXI
3480DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \
3481    "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n",
3482    QEMU_ARCH_ALL)
3483STEXI
3484@item -qmp-pretty @var{dev}
3485@findex -qmp-pretty
3486Like -qmp but uses pretty JSON formatting.
3487ETEXI
3488
3489DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
3490    "-mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]\n", QEMU_ARCH_ALL)
3491STEXI
3492@item -mon [chardev=]name[,mode=readline|control][,pretty[=on|off]]
3493@findex -mon
3494Setup monitor on chardev @var{name}. @code{pretty} turns on JSON pretty printing
3495easing human reading and debugging.
3496ETEXI
3497
3498DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
3499    "-debugcon dev   redirect the debug console to char device 'dev'\n",
3500    QEMU_ARCH_ALL)
3501STEXI
3502@item -debugcon @var{dev}
3503@findex -debugcon
3504Redirect the debug console to host device @var{dev} (same devices as the
3505serial port).  The debug console is an I/O port which is typically port
35060xe9; writing to that I/O port sends output to this device.
3507The default device is @code{vc} in graphical mode and @code{stdio} in
3508non graphical mode.
3509ETEXI
3510
3511DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
3512    "-pidfile file   write PID to 'file'\n", QEMU_ARCH_ALL)
3513STEXI
3514@item -pidfile @var{file}
3515@findex -pidfile
3516Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
3517from a script.
3518ETEXI
3519
3520DEF("singlestep", 0, QEMU_OPTION_singlestep, \
3521    "-singlestep     always run in singlestep mode\n", QEMU_ARCH_ALL)
3522STEXI
3523@item -singlestep
3524@findex -singlestep
3525Run the emulation in single step mode.
3526ETEXI
3527
3528DEF("S", 0, QEMU_OPTION_S, \
3529    "-S              freeze CPU at startup (use 'c' to start execution)\n",
3530    QEMU_ARCH_ALL)
3531STEXI
3532@item -S
3533@findex -S
3534Do not start CPU at startup (you must type 'c' in the monitor).
3535ETEXI
3536
3537DEF("realtime", HAS_ARG, QEMU_OPTION_realtime,
3538    "-realtime [mlock=on|off]\n"
3539    "                run qemu with realtime features\n"
3540    "                mlock=on|off controls mlock support (default: on)\n",
3541    QEMU_ARCH_ALL)
3542STEXI
3543@item -realtime mlock=on|off
3544@findex -realtime
3545Run qemu with realtime features.
3546mlocking qemu and guest memory can be enabled via @option{mlock=on}
3547(enabled by default).
3548ETEXI
3549
3550DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
3551    "-gdb dev        wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL)
3552STEXI
3553@item -gdb @var{dev}
3554@findex -gdb
3555Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
3556connections will likely be TCP-based, but also UDP, pseudo TTY, or even
3557stdio are reasonable use case. The latter is allowing to start QEMU from
3558within gdb and establish the connection via a pipe:
3559@example
3560(gdb) target remote | exec qemu-system-i386 -gdb stdio ...
3561@end example
3562ETEXI
3563
3564DEF("s", 0, QEMU_OPTION_s, \
3565    "-s              shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
3566    QEMU_ARCH_ALL)
3567STEXI
3568@item -s
3569@findex -s
3570Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
3571(@pxref{gdb_usage}).
3572ETEXI
3573
3574DEF("d", HAS_ARG, QEMU_OPTION_d, \
3575    "-d item1,...    enable logging of specified items (use '-d help' for a list of log items)\n",
3576    QEMU_ARCH_ALL)
3577STEXI
3578@item -d @var{item1}[,...]
3579@findex -d
3580Enable logging of specified items. Use '-d help' for a list of log items.
3581ETEXI
3582
3583DEF("D", HAS_ARG, QEMU_OPTION_D, \
3584    "-D logfile      output log to logfile (default stderr)\n",
3585    QEMU_ARCH_ALL)
3586STEXI
3587@item -D @var{logfile}
3588@findex -D
3589Output log in @var{logfile} instead of to stderr
3590ETEXI
3591
3592DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \
3593    "-dfilter range,..  filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n",
3594    QEMU_ARCH_ALL)
3595STEXI
3596@item -dfilter @var{range1}[,...]
3597@findex -dfilter
3598Filter debug output to that relevant to a range of target addresses. The filter
3599spec can be either @var{start}+@var{size}, @var{start}-@var{size} or
3600@var{start}..@var{end} where @var{start} @var{end} and @var{size} are the
3601addresses and sizes required. For example:
3602@example
3603    -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000
3604@end example
3605Will dump output for any code in the 0x1000 sized block starting at 0x8000 and
3606the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized
3607block starting at 0xffffffc00005f000.
3608ETEXI
3609
3610DEF("L", HAS_ARG, QEMU_OPTION_L, \
3611    "-L path         set the directory for the BIOS, VGA BIOS and keymaps\n",
3612    QEMU_ARCH_ALL)
3613STEXI
3614@item -L  @var{path}
3615@findex -L
3616Set the directory for the BIOS, VGA BIOS and keymaps.
3617
3618To list all the data directories, use @code{-L help}.
3619ETEXI
3620
3621DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
3622    "-bios file      set the filename for the BIOS\n", QEMU_ARCH_ALL)
3623STEXI
3624@item -bios @var{file}
3625@findex -bios
3626Set the filename for the BIOS.
3627ETEXI
3628
3629DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
3630    "-enable-kvm     enable KVM full virtualization support\n", QEMU_ARCH_ALL)
3631STEXI
3632@item -enable-kvm
3633@findex -enable-kvm
3634Enable KVM full virtualization support. This option is only available
3635if KVM support is enabled when compiling.
3636ETEXI
3637
3638DEF("enable-hax", 0, QEMU_OPTION_enable_hax, \
3639    "-enable-hax     enable HAX virtualization support\n", QEMU_ARCH_I386)
3640STEXI
3641@item -enable-hax
3642@findex -enable-hax
3643Enable HAX (Hardware-based Acceleration eXecution) support. This option
3644is only available if HAX support is enabled when compiling. HAX is only
3645applicable to MAC and Windows platform, and thus does not conflict with
3646KVM.
3647ETEXI
3648
3649DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
3650    "-xen-domid id   specify xen guest domain id\n", QEMU_ARCH_ALL)
3651DEF("xen-create", 0, QEMU_OPTION_xen_create,
3652    "-xen-create     create domain using xen hypercalls, bypassing xend\n"
3653    "                warning: should not be used when xend is in use\n",
3654    QEMU_ARCH_ALL)
3655DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
3656    "-xen-attach     attach to existing xen domain\n"
3657    "                xend will use this when starting QEMU\n",
3658    QEMU_ARCH_ALL)
3659DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict,
3660    "-xen-domid-restrict     restrict set of available xen operations\n"
3661    "                        to specified domain id. (Does not affect\n"
3662    "                        xenpv machine type).\n",
3663    QEMU_ARCH_ALL)
3664STEXI
3665@item -xen-domid @var{id}
3666@findex -xen-domid
3667Specify xen guest domain @var{id} (XEN only).
3668@item -xen-create
3669@findex -xen-create
3670Create domain using xen hypercalls, bypassing xend.
3671Warning: should not be used when xend is in use (XEN only).
3672@item -xen-attach
3673@findex -xen-attach
3674Attach to existing xen domain.
3675xend will use this when starting QEMU (XEN only).
3676@findex -xen-domid-restrict
3677Restrict set of available xen operations to specified domain id (XEN only).
3678ETEXI
3679
3680DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
3681    "-no-reboot      exit instead of rebooting\n", QEMU_ARCH_ALL)
3682STEXI
3683@item -no-reboot
3684@findex -no-reboot
3685Exit instead of rebooting.
3686ETEXI
3687
3688DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
3689    "-no-shutdown    stop before shutdown\n", QEMU_ARCH_ALL)
3690STEXI
3691@item -no-shutdown
3692@findex -no-shutdown
3693Don't exit QEMU on guest shutdown, but instead only stop the emulation.
3694This allows for instance switching to monitor to commit changes to the
3695disk image.
3696ETEXI
3697
3698DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
3699    "-loadvm [tag|id]\n" \
3700    "                start right away with a saved state (loadvm in monitor)\n",
3701    QEMU_ARCH_ALL)
3702STEXI
3703@item -loadvm @var{file}
3704@findex -loadvm
3705Start right away with a saved state (@code{loadvm} in monitor)
3706ETEXI
3707
3708#ifndef _WIN32
3709DEF("daemonize", 0, QEMU_OPTION_daemonize, \
3710    "-daemonize      daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
3711#endif
3712STEXI
3713@item -daemonize
3714@findex -daemonize
3715Daemonize the QEMU process after initialization.  QEMU will not detach from
3716standard IO until it is ready to receive connections on any of its devices.
3717This option is a useful way for external programs to launch QEMU without having
3718to cope with initialization race conditions.
3719ETEXI
3720
3721DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
3722    "-option-rom rom load a file, rom, into the option ROM space\n",
3723    QEMU_ARCH_ALL)
3724STEXI
3725@item -option-rom @var{file}
3726@findex -option-rom
3727Load the contents of @var{file} as an option ROM.
3728This option is useful to load things like EtherBoot.
3729ETEXI
3730
3731HXCOMM Silently ignored for compatibility
3732DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL)
3733
3734HXCOMM Options deprecated by -rtc
3735DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
3736DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
3737
3738DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
3739    "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
3740    "                set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
3741    QEMU_ARCH_ALL)
3742
3743STEXI
3744
3745@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
3746@findex -rtc
3747Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
3748UTC or local time, respectively. @code{localtime} is required for correct date in
3749MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
3750format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
3751
3752By default the RTC is driven by the host system time. This allows using of the
3753RTC as accurate reference clock inside the guest, specifically if the host
3754time is smoothly following an accurate external reference clock, e.g. via NTP.
3755If you want to isolate the guest time from the host, you can set @option{clock}
3756to @code{rt} instead.  To even prevent it from progressing during suspension,
3757you can set it to @code{vm}.
3758
3759Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
3760specifically with Windows' ACPI HAL. This option will try to figure out how
3761many timer interrupts were not processed by the Windows guest and will
3762re-inject them.
3763ETEXI
3764
3765DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
3766    "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \
3767    "                enable virtual instruction counter with 2^N clock ticks per\n" \
3768    "                instruction, enable aligning the host and virtual clocks\n" \
3769    "                or disable real time cpu sleeping\n", QEMU_ARCH_ALL)
3770STEXI
3771@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}]
3772@findex -icount
3773Enable virtual instruction counter.  The virtual cpu will execute one
3774instruction every 2^@var{N} ns of virtual time.  If @code{auto} is specified
3775then the virtual cpu speed will be automatically adjusted to keep virtual
3776time within a few seconds of real time.
3777
3778When the virtual cpu is sleeping, the virtual time will advance at default
3779speed unless @option{sleep=on|off} is specified.
3780With @option{sleep=on|off}, the virtual time will jump to the next timer deadline
3781instantly whenever the virtual cpu goes to sleep mode and will not advance
3782if no timer is enabled. This behavior give deterministic execution times from
3783the guest point of view.
3784
3785Note that while this option can give deterministic behavior, it does not
3786provide cycle accurate emulation.  Modern CPUs contain superscalar out of
3787order cores with complex cache hierarchies.  The number of instructions
3788executed often has little or no correlation with actual performance.
3789
3790@option{align=on} will activate the delay algorithm which will try
3791to synchronise the host clock and the virtual clock. The goal is to
3792have a guest running at the real frequency imposed by the shift option.
3793Whenever the guest clock is behind the host clock and if
3794@option{align=on} is specified then we print a message to the user
3795to inform about the delay.
3796Currently this option does not work when @option{shift} is @code{auto}.
3797Note: The sync algorithm will work for those shift values for which
3798the guest clock runs ahead of the host clock. Typically this happens
3799when the shift value is high (how high depends on the host machine).
3800
3801When @option{rr} option is specified deterministic record/replay is enabled.
3802Replay log is written into @var{filename} file in record mode and
3803read from this file in replay mode.
3804
3805Option rrsnapshot is used to create new vm snapshot named @var{snapshot}
3806at the start of execution recording. In replay mode this option is used
3807to load the initial VM state.
3808ETEXI
3809
3810DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
3811    "-watchdog model\n" \
3812    "                enable virtual hardware watchdog [default=none]\n",
3813    QEMU_ARCH_ALL)
3814STEXI
3815@item -watchdog @var{model}
3816@findex -watchdog
3817Create a virtual hardware watchdog device.  Once enabled (by a guest
3818action), the watchdog must be periodically polled by an agent inside
3819the guest or else the guest will be restarted. Choose a model for
3820which your guest has drivers.
3821
3822The @var{model} is the model of hardware watchdog to emulate. Use
3823@code{-watchdog help} to list available hardware models. Only one
3824watchdog can be enabled for a guest.
3825
3826The following models may be available:
3827@table @option
3828@item ib700
3829iBASE 700 is a very simple ISA watchdog with a single timer.
3830@item i6300esb
3831Intel 6300ESB I/O controller hub is a much more featureful PCI-based
3832dual-timer watchdog.
3833@item diag288
3834A virtual watchdog for s390x backed by the diagnose 288 hypercall
3835(currently KVM only).
3836@end table
3837ETEXI
3838
3839DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
3840    "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
3841    "                action when watchdog fires [default=reset]\n",
3842    QEMU_ARCH_ALL)
3843STEXI
3844@item -watchdog-action @var{action}
3845@findex -watchdog-action
3846
3847The @var{action} controls what QEMU will do when the watchdog timer
3848expires.
3849The default is
3850@code{reset} (forcefully reset the guest).
3851Other possible actions are:
3852@code{shutdown} (attempt to gracefully shutdown the guest),
3853@code{poweroff} (forcefully poweroff the guest),
3854@code{pause} (pause the guest),
3855@code{debug} (print a debug message and continue), or
3856@code{none} (do nothing).
3857
3858Note that the @code{shutdown} action requires that the guest responds
3859to ACPI signals, which it may not be able to do in the sort of
3860situations where the watchdog would have expired, and thus
3861@code{-watchdog-action shutdown} is not recommended for production use.
3862
3863Examples:
3864
3865@table @code
3866@item -watchdog i6300esb -watchdog-action pause
3867@itemx -watchdog ib700
3868@end table
3869ETEXI
3870
3871DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
3872    "-echr chr       set terminal escape character instead of ctrl-a\n",
3873    QEMU_ARCH_ALL)
3874STEXI
3875
3876@item -echr @var{numeric_ascii_value}
3877@findex -echr
3878Change the escape character used for switching to the monitor when using
3879monitor and serial sharing.  The default is @code{0x01} when using the
3880@code{-nographic} option.  @code{0x01} is equal to pressing
3881@code{Control-a}.  You can select a different character from the ascii
3882control keys where 1 through 26 map to Control-a through Control-z.  For
3883instance you could use the either of the following to change the escape
3884character to Control-t.
3885@table @code
3886@item -echr 0x14
3887@itemx -echr 20
3888@end table
3889ETEXI
3890
3891DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
3892    "-virtioconsole c\n" \
3893    "                set virtio console\n", QEMU_ARCH_ALL)
3894STEXI
3895@item -virtioconsole @var{c}
3896@findex -virtioconsole
3897Set virtio console.
3898
3899This option is maintained for backward compatibility.
3900
3901Please use @code{-device virtconsole} for the new way of invocation.
3902ETEXI
3903
3904DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
3905    "-show-cursor    show cursor\n", QEMU_ARCH_ALL)
3906STEXI
3907@item -show-cursor
3908@findex -show-cursor
3909Show cursor.
3910ETEXI
3911
3912DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
3913    "-tb-size n      set TB size\n", QEMU_ARCH_ALL)
3914STEXI
3915@item -tb-size @var{n}
3916@findex -tb-size
3917Set TB size.
3918ETEXI
3919
3920DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
3921    "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \
3922    "-incoming rdma:host:port[,ipv4][,ipv6]\n" \
3923    "-incoming unix:socketpath\n" \
3924    "                prepare for incoming migration, listen on\n" \
3925    "                specified protocol and socket address\n" \
3926    "-incoming fd:fd\n" \
3927    "-incoming exec:cmdline\n" \
3928    "                accept incoming migration on given file descriptor\n" \
3929    "                or from given external command\n" \
3930    "-incoming defer\n" \
3931    "                wait for the URI to be specified via migrate_incoming\n",
3932    QEMU_ARCH_ALL)
3933STEXI
3934@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6]
3935@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6]
3936@findex -incoming
3937Prepare for incoming migration, listen on a given tcp port.
3938
3939@item -incoming unix:@var{socketpath}
3940Prepare for incoming migration, listen on a given unix socket.
3941
3942@item -incoming fd:@var{fd}
3943Accept incoming migration from a given filedescriptor.
3944
3945@item -incoming exec:@var{cmdline}
3946Accept incoming migration as an output from specified external command.
3947
3948@item -incoming defer
3949Wait for the URI to be specified via migrate_incoming.  The monitor can
3950be used to change settings (such as migration parameters) prior to issuing
3951the migrate_incoming to allow the migration to begin.
3952ETEXI
3953
3954DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \
3955    "-only-migratable     allow only migratable devices\n", QEMU_ARCH_ALL)
3956STEXI
3957@item -only-migratable
3958@findex -only-migratable
3959Only allow migratable devices. Devices will not be allowed to enter an
3960unmigratable state.
3961ETEXI
3962
3963DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
3964    "-nodefaults     don't create default devices\n", QEMU_ARCH_ALL)
3965STEXI
3966@item -nodefaults
3967@findex -nodefaults
3968Don't create default devices. Normally, QEMU sets the default devices like serial
3969port, parallel port, virtual console, monitor device, VGA adapter, floppy and
3970CD-ROM drive and others. The @code{-nodefaults} option will disable all those
3971default devices.
3972ETEXI
3973
3974#ifndef _WIN32
3975DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
3976    "-chroot dir     chroot to dir just before starting the VM\n",
3977    QEMU_ARCH_ALL)
3978#endif
3979STEXI
3980@item -chroot @var{dir}
3981@findex -chroot
3982Immediately before starting guest execution, chroot to the specified
3983directory.  Especially useful in combination with -runas.
3984ETEXI
3985
3986#ifndef _WIN32
3987DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
3988    "-runas user     change to user id user just before starting the VM\n",
3989    QEMU_ARCH_ALL)
3990#endif
3991STEXI
3992@item -runas @var{user}
3993@findex -runas
3994Immediately before starting guest execution, drop root privileges, switching
3995to the specified user.
3996ETEXI
3997
3998DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
3999    "-prom-env variable=value\n"
4000    "                set OpenBIOS nvram variables\n",
4001    QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
4002STEXI
4003@item -prom-env @var{variable}=@var{value}
4004@findex -prom-env
4005Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
4006ETEXI
4007DEF("semihosting", 0, QEMU_OPTION_semihosting,
4008    "-semihosting    semihosting mode\n",
4009    QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
4010    QEMU_ARCH_MIPS)
4011STEXI
4012@item -semihosting
4013@findex -semihosting
4014Enable semihosting mode (ARM, M68K, Xtensa, MIPS only).
4015ETEXI
4016DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config,
4017    "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \
4018    "                semihosting configuration\n",
4019QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
4020QEMU_ARCH_MIPS)
4021STEXI
4022@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]
4023@findex -semihosting-config
4024Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only).
4025@table @option
4026@item target=@code{native|gdb|auto}
4027Defines where the semihosting calls will be addressed, to QEMU (@code{native})
4028or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb}
4029during debug sessions and @code{native} otherwise.
4030@item arg=@var{str1},arg=@var{str2},...
4031Allows the user to pass input arguments, and can be used multiple times to build
4032up a list. The old-style @code{-kernel}/@code{-append} method of passing a
4033command line is still supported for backward compatibility. If both the
4034@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are
4035specified, the former is passed to semihosting as it always takes precedence.
4036@end table
4037ETEXI
4038DEF("old-param", 0, QEMU_OPTION_old_param,
4039    "-old-param      old param mode\n", QEMU_ARCH_ARM)
4040STEXI
4041@item -old-param
4042@findex -old-param (ARM)
4043Old param mode (ARM only).
4044ETEXI
4045
4046DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
4047    "-sandbox on[,obsolete=allow|deny][,elevateprivileges=allow|deny|children]\n" \
4048    "          [,spawn=allow|deny][,resourcecontrol=allow|deny]\n" \
4049    "                Enable seccomp mode 2 system call filter (default 'off').\n" \
4050    "                use 'obsolete' to allow obsolete system calls that are provided\n" \
4051    "                    by the kernel, but typically no longer used by modern\n" \
4052    "                    C library implementations.\n" \
4053    "                use 'elevateprivileges' to allow or deny QEMU process to elevate\n" \
4054    "                    its privileges by blacklisting all set*uid|gid system calls.\n" \
4055    "                    The value 'children' will deny set*uid|gid system calls for\n" \
4056    "                    main QEMU process but will allow forks and execves to run unprivileged\n" \
4057    "                use 'spawn' to avoid QEMU to spawn new threads or processes by\n" \
4058    "                     blacklisting *fork and execve\n" \
4059    "                use 'resourcecontrol' to disable process affinity and schedular priority\n",
4060    QEMU_ARCH_ALL)
4061STEXI
4062@item -sandbox @var{arg}[,obsolete=@var{string}][,elevateprivileges=@var{string}][,spawn=@var{string}][,resourcecontrol=@var{string}]
4063@findex -sandbox
4064Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
4065disable it.  The default is 'off'.
4066@table @option
4067@item obsolete=@var{string}
4068Enable Obsolete system calls
4069@item elevateprivileges=@var{string}
4070Disable set*uid|gid system calls
4071@item spawn=@var{string}
4072Disable *fork and execve
4073@item resourcecontrol=@var{string}
4074Disable process affinity and schedular priority
4075@end table
4076ETEXI
4077
4078DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
4079    "-readconfig <file>\n", QEMU_ARCH_ALL)
4080STEXI
4081@item -readconfig @var{file}
4082@findex -readconfig
4083Read device configuration from @var{file}. This approach is useful when you want to spawn
4084QEMU process with many command line options but you don't want to exceed the command line
4085character limit.
4086ETEXI
4087DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
4088    "-writeconfig <file>\n"
4089    "                read/write config file\n", QEMU_ARCH_ALL)
4090STEXI
4091@item -writeconfig @var{file}
4092@findex -writeconfig
4093Write device configuration to @var{file}. The @var{file} can be either filename to save
4094command line and device configuration into file or dash @code{-}) character to print the
4095output to stdout. This can be later used as input file for @code{-readconfig} option.
4096ETEXI
4097HXCOMM Deprecated, same as -no-user-config
4098DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, "", QEMU_ARCH_ALL)
4099DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
4100    "-no-user-config\n"
4101    "                do not load default user-provided config files at startup\n",
4102    QEMU_ARCH_ALL)
4103STEXI
4104@item -no-user-config
4105@findex -no-user-config
4106The @code{-no-user-config} option makes QEMU not load any of the user-provided
4107config files on @var{sysconfdir}.
4108ETEXI
4109DEF("trace", HAS_ARG, QEMU_OPTION_trace,
4110    "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
4111    "                specify tracing options\n",
4112    QEMU_ARCH_ALL)
4113STEXI
4114HXCOMM This line is not accurate, as some sub-options are backend-specific but
4115HXCOMM HX does not support conditional compilation of text.
4116@item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}]
4117@findex -trace
4118@include qemu-option-trace.texi
4119ETEXI
4120
4121HXCOMM Internal use
4122DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL)
4123DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL)
4124
4125#ifdef __linux__
4126DEF("enable-fips", 0, QEMU_OPTION_enablefips,
4127    "-enable-fips    enable FIPS 140-2 compliance\n",
4128    QEMU_ARCH_ALL)
4129#endif
4130STEXI
4131@item -enable-fips
4132@findex -enable-fips
4133Enable FIPS 140-2 compliance mode.
4134ETEXI
4135
4136HXCOMM Deprecated by -machine accel=tcg property
4137DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386)
4138
4139HXCOMM Deprecated by kvm-pit driver properties
4140DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection,
4141    "", QEMU_ARCH_I386)
4142
4143HXCOMM Deprecated (ignored)
4144DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386)
4145
4146HXCOMM Deprecated by -machine kernel_irqchip=on|off property
4147DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386)
4148
4149HXCOMM Deprecated (ignored)
4150DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL)
4151
4152DEF("msg", HAS_ARG, QEMU_OPTION_msg,
4153    "-msg timestamp[=on|off]\n"
4154    "                change the format of messages\n"
4155    "                on|off controls leading timestamps (default:on)\n",
4156    QEMU_ARCH_ALL)
4157STEXI
4158@item -msg timestamp[=on|off]
4159@findex -msg
4160prepend a timestamp to each log message.(default:on)
4161ETEXI
4162
4163DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate,
4164    "-dump-vmstate <file>\n"
4165    "                Output vmstate information in JSON format to file.\n"
4166    "                Use the scripts/vmstate-static-checker.py file to\n"
4167    "                check for possible regressions in migration code\n"
4168    "                by comparing two such vmstate dumps.\n",
4169    QEMU_ARCH_ALL)
4170STEXI
4171@item -dump-vmstate @var{file}
4172@findex -dump-vmstate
4173Dump json-encoded vmstate information for current machine type to file
4174in @var{file}
4175ETEXI
4176
4177STEXI
4178@end table
4179ETEXI
4180DEFHEADING()
4181DEFHEADING(Generic object creation)
4182STEXI
4183@table @option
4184ETEXI
4185
4186DEF("object", HAS_ARG, QEMU_OPTION_object,
4187    "-object TYPENAME[,PROP1=VALUE1,...]\n"
4188    "                create a new object of type TYPENAME setting properties\n"
4189    "                in the order they are specified.  Note that the 'id'\n"
4190    "                property must be set.  These objects are placed in the\n"
4191    "                '/objects' path.\n",
4192    QEMU_ARCH_ALL)
4193STEXI
4194@item -object @var{typename}[,@var{prop1}=@var{value1},...]
4195@findex -object
4196Create a new object of type @var{typename} setting properties
4197in the order they are specified.  Note that the 'id'
4198property must be set.  These objects are placed in the
4199'/objects' path.
4200
4201@table @option
4202
4203@item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off},discard-data=@var{on|off}
4204
4205Creates a memory file backend object, which can be used to back
4206the guest RAM with huge pages. The @option{id} parameter is a
4207unique ID that will be used to reference this memory region
4208when configuring the @option{-numa} argument. The @option{size}
4209option provides the size of the memory region, and accepts
4210common suffixes, eg @option{500M}. The @option{mem-path} provides
4211the path to either a shared memory or huge page filesystem mount.
4212The @option{share} boolean option determines whether the memory
4213region is marked as private to QEMU, or shared. The latter allows
4214a co-operating external process to access the QEMU memory region.
4215Setting the @option{discard-data} boolean option to @var{on}
4216indicates that file contents can be destroyed when QEMU exits,
4217to avoid unnecessarily flushing data to the backing file.  Note
4218that @option{discard-data} is only an optimization, and QEMU
4219might not discard file contents if it aborts unexpectedly or is
4220terminated using SIGKILL.
4221
4222@item -object rng-random,id=@var{id},filename=@var{/dev/random}
4223
4224Creates a random number generator backend which obtains entropy from
4225a device on the host. The @option{id} parameter is a unique ID that
4226will be used to reference this entropy backend from the @option{virtio-rng}
4227device. The @option{filename} parameter specifies which file to obtain
4228entropy from and if omitted defaults to @option{/dev/random}.
4229
4230@item -object rng-egd,id=@var{id},chardev=@var{chardevid}
4231
4232Creates a random number generator backend which obtains entropy from
4233an external daemon running on the host. The @option{id} parameter is
4234a unique ID that will be used to reference this entropy backend from
4235the @option{virtio-rng} device. The @option{chardev} parameter is
4236the unique ID of a character device backend that provides the connection
4237to the RNG daemon.
4238
4239@item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off}
4240
4241Creates a TLS anonymous credentials object, which can be used to provide
4242TLS support on network backends. The @option{id} parameter is a unique
4243ID which network backends will use to access the credentials. The
4244@option{endpoint} is either @option{server} or @option{client} depending
4245on whether the QEMU network backend that uses the credentials will be
4246acting as a client or as a server. If @option{verify-peer} is enabled
4247(the default) then once the handshake is completed, the peer credentials
4248will be verified, though this is a no-op for anonymous credentials.
4249
4250The @var{dir} parameter tells QEMU where to find the credential
4251files. For server endpoints, this directory may contain a file
4252@var{dh-params.pem} providing diffie-hellman parameters to use
4253for the TLS server. If the file is missing, QEMU will generate
4254a set of DH parameters at startup. This is a computationally
4255expensive operation that consumes random pool entropy, so it is
4256recommended that a persistent set of parameters be generated
4257upfront and saved.
4258
4259@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}
4260
4261Creates a TLS anonymous credentials object, which can be used to provide
4262TLS support on network backends. The @option{id} parameter is a unique
4263ID which network backends will use to access the credentials. The
4264@option{endpoint} is either @option{server} or @option{client} depending
4265on whether the QEMU network backend that uses the credentials will be
4266acting as a client or as a server. If @option{verify-peer} is enabled
4267(the default) then once the handshake is completed, the peer credentials
4268will be verified. With x509 certificates, this implies that the clients
4269must be provided with valid client certificates too.
4270
4271The @var{dir} parameter tells QEMU where to find the credential
4272files. For server endpoints, this directory may contain a file
4273@var{dh-params.pem} providing diffie-hellman parameters to use
4274for the TLS server. If the file is missing, QEMU will generate
4275a set of DH parameters at startup. This is a computationally
4276expensive operation that consumes random pool entropy, so it is
4277recommended that a persistent set of parameters be generated
4278upfront and saved.
4279
4280For x509 certificate credentials the directory will contain further files
4281providing the x509 certificates. The certificates must be stored
4282in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional),
4283@var{server-cert.pem} (only servers), @var{server-key.pem} (only servers),
4284@var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients).
4285
4286For the @var{server-key.pem} and @var{client-key.pem} files which
4287contain sensitive private keys, it is possible to use an encrypted
4288version by providing the @var{passwordid} parameter. This provides
4289the ID of a previously created @code{secret} object containing the
4290password for decryption.
4291
4292@item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}]
4293
4294Interval @var{t} can't be 0, this filter batches the packet delivery: all
4295packets arriving in a given interval on netdev @var{netdevid} are delayed
4296until the end of the interval. Interval is in microseconds.
4297@option{status} is optional that indicate whether the netfilter is
4298on (enabled) or off (disabled), the default status for netfilter will be 'on'.
4299
4300queue @var{all|rx|tx} is an option that can be applied to any netfilter.
4301
4302@option{all}: the filter is attached both to the receive and the transmit
4303              queue of the netdev (default).
4304
4305@option{rx}: the filter is attached to the receive queue of the netdev,
4306             where it will receive packets sent to the netdev.
4307
4308@option{tx}: the filter is attached to the transmit queue of the netdev,
4309             where it will receive packets sent by the netdev.
4310
4311@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4312
4313filter-mirror on netdev @var{netdevid},mirror net packet to chardev@var{chardevid}, if it has the vnet_hdr_support flag, filter-mirror will mirror packet with vnet_hdr_len.
4314
4315@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},outdev=@var{chardevid},queue=@var{all|rx|tx}[,vnet_hdr_support]
4316
4317filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev
4318@var{chardevid},and redirect indev's packet to filter.if it has the vnet_hdr_support flag,
4319filter-redirector will redirect packet with vnet_hdr_len.
4320Create a filter-redirector we need to differ outdev id from indev id, id can not
4321be the same. we can just use indev or outdev, but at least one of indev or outdev
4322need to be specified.
4323
4324@item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},queue=@var{all|rx|tx},[vnet_hdr_support]
4325
4326Filter-rewriter is a part of COLO project.It will rewrite tcp packet to
4327secondary from primary to keep secondary tcp connection,and rewrite
4328tcp packet to primary from secondary make tcp packet can be handled by
4329client.if it has the vnet_hdr_support flag, we can parse packet with vnet header.
4330
4331usage:
4332colo secondary:
4333-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4334-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4335-object filter-rewriter,id=rew0,netdev=hn0,queue=all
4336
4337@item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}]
4338
4339Dump the network traffic on netdev @var{dev} to the file specified by
4340@var{filename}. At most @var{len} bytes (64k by default) per packet are stored.
4341The file format is libpcap, so it can be analyzed with tools such as tcpdump
4342or Wireshark.
4343
4344@item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},outdev=@var{chardevid}[,vnet_hdr_support]
4345
4346Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with
4347secondary packet. If the packets are same, we will output primary
4348packet to outdev@var{chardevid}, else we will notify colo-frame
4349do checkpoint and send primary packet to outdev@var{chardevid}.
4350if it has the vnet_hdr_support flag, colo compare will send/recv packet with vnet_hdr_len.
4351
4352we must use it with the help of filter-mirror and filter-redirector.
4353
4354@example
4355
4356primary:
4357-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown
4358-device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66
4359-chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait
4360-chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait
4361-chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait
4362-chardev socket,id=compare0-0,host=3.3.3.3,port=9001
4363-chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait
4364-chardev socket,id=compare_out0,host=3.3.3.3,port=9005
4365-object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0
4366-object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out
4367-object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0
4368-object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0
4369
4370secondary:
4371-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown
4372-device e1000,netdev=hn0,mac=52:a4:00:12:78:66
4373-chardev socket,id=red0,host=3.3.3.3,port=9003
4374-chardev socket,id=red1,host=3.3.3.3,port=9004
4375-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
4376-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
4377
4378@end example
4379
4380If you want to know the detail of above command line, you can read
4381the colo-compare git log.
4382
4383@item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}]
4384
4385Creates a cryptodev backend which executes crypto opreation from
4386the QEMU cipher APIS. The @var{id} parameter is
4387a unique ID that will be used to reference this cryptodev backend from
4388the @option{virtio-crypto} device. The @var{queues} parameter is optional,
4389which specify the queue number of cryptodev backend, the default of
4390@var{queues} is 1.
4391
4392@example
4393
4394 # qemu-system-x86_64 \
4395   [...] \
4396       -object cryptodev-backend-builtin,id=cryptodev0 \
4397       -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4398   [...]
4399@end example
4400
4401@item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4402@item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4403
4404Defines a secret to store a password, encryption key, or some other sensitive
4405data. The sensitive data can either be passed directly via the @var{data}
4406parameter, or indirectly via the @var{file} parameter. Using the @var{data}
4407parameter is insecure unless the sensitive data is encrypted.
4408
4409The sensitive data can be provided in raw format (the default), or base64.
4410When encoded as JSON, the raw format only supports valid UTF-8 characters,
4411so base64 is recommended for sending binary data. QEMU will convert from
4412which ever format is provided to the format it needs internally. eg, an
4413RBD password can be provided in raw format, even though it will be base64
4414encoded when passed onto the RBD sever.
4415
4416For added protection, it is possible to encrypt the data associated with
4417a secret using the AES-256-CBC cipher. Use of encryption is indicated
4418by providing the @var{keyid} and @var{iv} parameters. The @var{keyid}
4419parameter provides the ID of a previously defined secret that contains
4420the AES-256 decryption key. This key should be 32-bytes long and be
4421base64 encoded. The @var{iv} parameter provides the random initialization
4422vector used for encryption of this particular secret and should be a
4423base64 encrypted string of the 16-byte IV.
4424
4425The simplest (insecure) usage is to provide the secret inline
4426
4427@example
4428
4429 # $QEMU -object secret,id=sec0,data=letmein,format=raw
4430
4431@end example
4432
4433The simplest secure usage is to provide the secret via a file
4434
4435 # printf "letmein" > mypasswd.txt
4436 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw
4437
4438For greater security, AES-256-CBC should be used. To illustrate usage,
4439consider the openssl command line tool which can encrypt the data. Note
4440that when encrypting, the plaintext must be padded to the cipher block
4441size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm.
4442
4443First a master key needs to be created in base64 encoding:
4444
4445@example
4446 # openssl rand -base64 32 > key.b64
4447 # KEY=$(base64 -d key.b64 | hexdump  -v -e '/1 "%02X"')
4448@end example
4449
4450Each secret to be encrypted needs to have a random initialization vector
4451generated. These do not need to be kept secret
4452
4453@example
4454 # openssl rand -base64 16 > iv.b64
4455 # IV=$(base64 -d iv.b64 | hexdump  -v -e '/1 "%02X"')
4456@end example
4457
4458The secret to be defined can now be encrypted, in this case we're
4459telling openssl to base64 encode the result, but it could be left
4460as raw bytes if desired.
4461
4462@example
4463 # SECRET=$(printf "letmein" |
4464            openssl enc -aes-256-cbc -a -K $KEY -iv $IV)
4465@end example
4466
4467When launching QEMU, create a master secret pointing to @code{key.b64}
4468and specify that to be used to decrypt the user password. Pass the
4469contents of @code{iv.b64} to the second secret
4470
4471@example
4472 # $QEMU \
4473     -object secret,id=secmaster0,format=base64,file=key.b64 \
4474     -object secret,id=sec0,keyid=secmaster0,format=base64,\
4475         data=$SECRET,iv=$(<iv.b64)
4476@end example
4477
4478@end table
4479
4480ETEXI
4481
4482
4483HXCOMM This is the last statement. Insert new options before this line!
4484STEXI
4485@end table
4486ETEXI
4487