xref: /openbmc/qemu/qemu-options.hx (revision 80e5db30)
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, tcg (default: tcg)\n"
35    "                kernel_irqchip=on|off controls accelerated irqchip support\n"
36    "                kernel_irqchip=on|off|split controls accelerated irqchip support (default=off)\n"
37    "                vmport=on|off|auto controls emulation of vmport (default: auto)\n"
38    "                kvm_shadow_mem=size of KVM shadow MMU in bytes\n"
39    "                dump-guest-core=on|off include guest memory in a core dump (default=on)\n"
40    "                mem-merge=on|off controls memory merge support (default: on)\n"
41    "                igd-passthru=on|off controls IGD GFX passthrough support (default=off)\n"
42    "                aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n"
43    "                dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n"
44    "                suppress-vmdesc=on|off disables self-describing migration (default=off)\n"
45    "                nvdimm=on|off controls NVDIMM support (default=off)\n"
46    "                enforce-config-section=on|off enforce configuration section migration (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. Supported machine properties are:
53@table @option
54@item accel=@var{accels1}[:@var{accels2}[:...]]
55This is used to enable an accelerator. Depending on the target architecture,
56kvm, xen, or tcg can be available. By default, tcg is used. If there is more
57than one accelerator specified, the next one is used if the previous one fails
58to initialize.
59@item kernel_irqchip=on|off
60Controls in-kernel irqchip support for the chosen accelerator when available.
61@item gfx_passthru=on|off
62Enables IGD GFX passthrough support for the chosen machine when available.
63@item vmport=on|off|auto
64Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the
65value based on accel. For accel=xen the default is off otherwise the default
66is on.
67@item kvm_shadow_mem=size
68Defines the size of the KVM shadow MMU.
69@item dump-guest-core=on|off
70Include guest memory in a core dump. The default is on.
71@item mem-merge=on|off
72Enables or disables memory merge support. This feature, when supported by
73the host, de-duplicates identical memory pages among VMs instances
74(enabled by default).
75@item aes-key-wrap=on|off
76Enables or disables AES key wrapping support on s390-ccw hosts. This feature
77controls whether AES wrapping keys will be created to allow
78execution of AES cryptographic functions.  The default is on.
79@item dea-key-wrap=on|off
80Enables or disables DEA key wrapping support on s390-ccw hosts. This feature
81controls whether DEA wrapping keys will be created to allow
82execution of DEA cryptographic functions.  The default is on.
83@item nvdimm=on|off
84Enables or disables NVDIMM support. The default is off.
85@end table
86ETEXI
87
88HXCOMM Deprecated by -machine
89DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL)
90
91DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
92    "-cpu cpu        select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL)
93STEXI
94@item -cpu @var{model}
95@findex -cpu
96Select CPU model (@code{-cpu help} for list and additional feature selection)
97ETEXI
98
99DEF("smp", HAS_ARG, QEMU_OPTION_smp,
100    "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
101    "                set the number of CPUs to 'n' [default=1]\n"
102    "                maxcpus= maximum number of total cpus, including\n"
103    "                offline CPUs for hotplug, etc\n"
104    "                cores= number of CPU cores on one socket\n"
105    "                threads= number of threads on one CPU core\n"
106    "                sockets= number of discrete sockets in the system\n",
107        QEMU_ARCH_ALL)
108STEXI
109@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
110@findex -smp
111Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
112CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
113to 4.
114For the PC target, the number of @var{cores} per socket, the number
115of @var{threads} per cores and the total number of @var{sockets} can be
116specified. Missing values will be computed. If any on the three values is
117given, the total number of CPUs @var{n} can be omitted. @var{maxcpus}
118specifies the maximum number of hotpluggable CPUs.
119ETEXI
120
121DEF("numa", HAS_ARG, QEMU_OPTION_numa,
122    "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n"
123    "-numa node[,memdev=id][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL)
124STEXI
125@item -numa node[,mem=@var{size}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}]
126@itemx -numa node[,memdev=@var{id}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}]
127@findex -numa
128Simulate a multi node NUMA system. If @samp{mem}, @samp{memdev}
129and @samp{cpus} are omitted, resources are split equally. Also, note
130that the -@option{numa} option doesn't allocate any of the specified
131resources. That is, it just assigns existing resources to NUMA nodes. This
132means that one still has to use the @option{-m}, @option{-smp} options
133to allocate RAM and VCPUs respectively, and possibly @option{-object}
134to specify the memory backend for the @samp{memdev} suboption.
135
136@samp{mem} and @samp{memdev} are mutually exclusive.  Furthermore, if one
137node uses @samp{memdev}, all of them have to use it.
138ETEXI
139
140DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
141    "-add-fd fd=fd,set=set[,opaque=opaque]\n"
142    "                Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL)
143STEXI
144@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}]
145@findex -add-fd
146
147Add a file descriptor to an fd set.  Valid options are:
148
149@table @option
150@item fd=@var{fd}
151This option defines the file descriptor of which a duplicate is added to fd set.
152The file descriptor cannot be stdin, stdout, or stderr.
153@item set=@var{set}
154This option defines the ID of the fd set to add the file descriptor to.
155@item opaque=@var{opaque}
156This option defines a free-form string that can be used to describe @var{fd}.
157@end table
158
159You can open an image using pre-opened file descriptors from an fd set:
160@example
161qemu-system-i386
162-add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
163-add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
164-drive file=/dev/fdset/2,index=0,media=disk
165@end example
166ETEXI
167
168DEF("set", HAS_ARG, QEMU_OPTION_set,
169    "-set group.id.arg=value\n"
170    "                set <arg> parameter for item <id> of type <group>\n"
171    "                i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL)
172STEXI
173@item -set @var{group}.@var{id}.@var{arg}=@var{value}
174@findex -set
175Set parameter @var{arg} for item @var{id} of type @var{group}
176ETEXI
177
178DEF("global", HAS_ARG, QEMU_OPTION_global,
179    "-global driver.property=value\n"
180    "-global driver=driver,property=property,value=value\n"
181    "                set a global default for a driver property\n",
182    QEMU_ARCH_ALL)
183STEXI
184@item -global @var{driver}.@var{prop}=@var{value}
185@itemx -global driver=@var{driver},property=@var{property},value=@var{value}
186@findex -global
187Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.:
188
189@example
190qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk
191@end example
192
193In particular, you can use this to set driver properties for devices which are
194created automatically by the machine model. To create a device which is not
195created automatically and set properties on it, use -@option{device}.
196
197-global @var{driver}.@var{prop}=@var{value} is shorthand for -global
198driver=@var{driver},property=@var{prop},value=@var{value}.  The
199longhand syntax works even when @var{driver} contains a dot.
200ETEXI
201
202DEF("boot", HAS_ARG, QEMU_OPTION_boot,
203    "-boot [order=drives][,once=drives][,menu=on|off]\n"
204    "      [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n"
205    "                'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
206    "                'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n"
207    "                'sp_time': the period that splash picture last if menu=on, unit is ms\n"
208    "                'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n",
209    QEMU_ARCH_ALL)
210STEXI
211@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]
212@findex -boot
213Specify boot order @var{drives} as a string of drive letters. Valid
214drive letters depend on the target architecture. The x86 PC uses: a, b
215(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
216from network adapter 1-4), hard disk boot is the default. To apply a
217particular boot order only on the first startup, specify it via
218@option{once}.
219
220Interactive boot menus/prompts can be enabled via @option{menu=on} as far
221as firmware/BIOS supports them. The default is non-interactive boot.
222
223A splash picture could be passed to bios, enabling user to show it as logo,
224when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
225supports them. Currently Seabios for X86 system support it.
226limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
227format(true color). The resolution should be supported by the SVGA mode, so
228the recommended is 320x240, 640x480, 800x640.
229
230A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms
231when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not
232reboot, qemu passes '-1' to bios by default. Currently Seabios for X86
233system support it.
234
235Do strict boot via @option{strict=on} as far as firmware/BIOS
236supports it. This only effects when boot priority is changed by
237bootindex options. The default is non-strict boot.
238
239@example
240# try to boot from network first, then from hard disk
241qemu-system-i386 -boot order=nc
242# boot from CD-ROM first, switch back to default order after reboot
243qemu-system-i386 -boot once=d
244# boot with a splash picture for 5 seconds.
245qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
246@end example
247
248Note: The legacy format '-boot @var{drives}' is still supported but its
249use is discouraged as it may be removed from future versions.
250ETEXI
251
252DEF("m", HAS_ARG, QEMU_OPTION_m,
253    "-m[emory] [size=]megs[,slots=n,maxmem=size]\n"
254    "                configure guest RAM\n"
255    "                size: initial amount of guest memory\n"
256    "                slots: number of hotplug slots (default: none)\n"
257    "                maxmem: maximum amount of guest memory (default: none)\n"
258    "NOTE: Some architectures might enforce a specific granularity\n",
259    QEMU_ARCH_ALL)
260STEXI
261@item -m [size=]@var{megs}[,slots=n,maxmem=size]
262@findex -m
263Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB.
264Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in
265megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem}
266could be used to set amount of hotpluggable memory slots and maximum amount of
267memory. Note that @var{maxmem} must be aligned to the page size.
268
269For example, the following command-line sets the guest startup RAM size to
2701GB, creates 3 slots to hotplug additional memory and sets the maximum
271memory the guest can reach to 4GB:
272
273@example
274qemu-system-x86_64 -m 1G,slots=3,maxmem=4G
275@end example
276
277If @var{slots} and @var{maxmem} are not specified, memory hotplug won't
278be enabled and the guest startup RAM will never increase.
279ETEXI
280
281DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
282    "-mem-path FILE  provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
283STEXI
284@item -mem-path @var{path}
285@findex -mem-path
286Allocate guest RAM from a temporarily created file in @var{path}.
287ETEXI
288
289DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
290    "-mem-prealloc   preallocate guest memory (use with -mem-path)\n",
291    QEMU_ARCH_ALL)
292STEXI
293@item -mem-prealloc
294@findex -mem-prealloc
295Preallocate memory when using -mem-path.
296ETEXI
297
298DEF("k", HAS_ARG, QEMU_OPTION_k,
299    "-k language     use keyboard layout (for example 'fr' for French)\n",
300    QEMU_ARCH_ALL)
301STEXI
302@item -k @var{language}
303@findex -k
304Use keyboard layout @var{language} (for example @code{fr} for
305French). This option is only needed where it is not easy to get raw PC
306keycodes (e.g. on Macs, with some X11 servers or with a VNC or curses
307display). You don't normally need to use it on PC/Linux or PC/Windows
308hosts.
309
310The available layouts are:
311@example
312ar  de-ch  es  fo     fr-ca  hu  ja  mk     no  pt-br  sv
313da  en-gb  et  fr     fr-ch  is  lt  nl     pl  ru     th
314de  en-us  fi  fr-be  hr     it  lv  nl-be  pt  sl     tr
315@end example
316
317The default is @code{en-us}.
318ETEXI
319
320
321DEF("audio-help", 0, QEMU_OPTION_audio_help,
322    "-audio-help     print list of audio drivers and their options\n",
323    QEMU_ARCH_ALL)
324STEXI
325@item -audio-help
326@findex -audio-help
327Will show the audio subsystem help: list of drivers, tunable
328parameters.
329ETEXI
330
331DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
332    "-soundhw c1,... enable audio support\n"
333    "                and only specified sound cards (comma separated list)\n"
334    "                use '-soundhw help' to get the list of supported cards\n"
335    "                use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL)
336STEXI
337@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
338@findex -soundhw
339Enable audio and selected sound hardware. Use 'help' to print all
340available sound hardware.
341
342@example
343qemu-system-i386 -soundhw sb16,adlib disk.img
344qemu-system-i386 -soundhw es1370 disk.img
345qemu-system-i386 -soundhw ac97 disk.img
346qemu-system-i386 -soundhw hda disk.img
347qemu-system-i386 -soundhw all disk.img
348qemu-system-i386 -soundhw help
349@end example
350
351Note that Linux's i810_audio OSS kernel (for AC97) module might
352require manually specifying clocking.
353
354@example
355modprobe i810_audio clocking=48000
356@end example
357ETEXI
358
359DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
360    "-balloon none   disable balloon device\n"
361    "-balloon virtio[,addr=str]\n"
362    "                enable virtio balloon device (default)\n", QEMU_ARCH_ALL)
363STEXI
364@item -balloon none
365@findex -balloon
366Disable balloon device.
367@item -balloon virtio[,addr=@var{addr}]
368Enable virtio balloon device (default), optionally with PCI address
369@var{addr}.
370ETEXI
371
372DEF("device", HAS_ARG, QEMU_OPTION_device,
373    "-device driver[,prop[=value][,...]]\n"
374    "                add device (based on driver)\n"
375    "                prop=value,... sets driver properties\n"
376    "                use '-device help' to print all possible drivers\n"
377    "                use '-device driver,help' to print all possible properties\n",
378    QEMU_ARCH_ALL)
379STEXI
380@item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
381@findex -device
382Add device @var{driver}.  @var{prop}=@var{value} sets driver
383properties.  Valid properties depend on the driver.  To get help on
384possible drivers and properties, use @code{-device help} and
385@code{-device @var{driver},help}.
386
387Some drivers are:
388@item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}]
389
390Add an IPMI BMC.  This is a simulation of a hardware management
391interface processor that normally sits on a system.  It provides
392a watchdog and the ability to reset and power control the system.
393You need to connect this to an IPMI interface to make it useful
394
395The IPMI slave address to use for the BMC.  The default is 0x20.
396This address is the BMC's address on the I2C network of management
397controllers.  If you don't know what this means, it is safe to ignore
398it.
399
400@item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}]
401
402Add a connection to an external IPMI BMC simulator.  Instead of
403locally emulating the BMC like the above item, instead connect
404to an external entity that provides the IPMI services.
405
406A connection is made to an external BMC simulator.  If you do this, it
407is strongly recommended that you use the "reconnect=" chardev option
408to reconnect to the simulator if the connection is lost.  Note that if
409this is not used carefully, it can be a security issue, as the
410interface has the ability to send resets, NMIs, and power off the VM.
411It's best if QEMU makes a connection to an external simulator running
412on a secure port on localhost, so neither the simulator nor QEMU is
413exposed to any outside network.
414
415See the "lanserv/README.vm" file in the OpenIPMI library for more
416details on the external interface.
417
418@item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
419
420Add a KCS IPMI interafce on the ISA bus.  This also adds a
421corresponding ACPI and SMBIOS entries, if appropriate.
422
423@table @option
424@item bmc=@var{id}
425The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above.
426@item ioport=@var{val}
427Define the I/O address of the interface.  The default is 0xca0 for KCS.
428@item irq=@var{val}
429Define the interrupt to use.  The default is 5.  To disable interrupts,
430set this to 0.
431@end table
432
433@item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}]
434
435Like the KCS interface, but defines a BT interface.  The default port is
4360xe4 and the default interrupt is 5.
437
438ETEXI
439
440DEF("name", HAS_ARG, QEMU_OPTION_name,
441    "-name string1[,process=string2][,debug-threads=on|off]\n"
442    "                set the name of the guest\n"
443    "                string1 sets the window title and string2 the process name (on Linux)\n"
444    "                When debug-threads is enabled, individual threads are given a separate name (on Linux)\n"
445    "                NOTE: The thread names are for debugging and not a stable API.\n",
446    QEMU_ARCH_ALL)
447STEXI
448@item -name @var{name}
449@findex -name
450Sets the @var{name} of the guest.
451This name will be displayed in the SDL window caption.
452The @var{name} will also be used for the VNC server.
453Also optionally set the top visible process name in Linux.
454Naming of individual threads can also be enabled on Linux to aid debugging.
455ETEXI
456
457DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
458    "-uuid %08x-%04x-%04x-%04x-%012x\n"
459    "                specify machine UUID\n", QEMU_ARCH_ALL)
460STEXI
461@item -uuid @var{uuid}
462@findex -uuid
463Set system UUID.
464ETEXI
465
466STEXI
467@end table
468ETEXI
469DEFHEADING()
470
471DEFHEADING(Block device options)
472STEXI
473@table @option
474ETEXI
475
476DEF("fda", HAS_ARG, QEMU_OPTION_fda,
477    "-fda/-fdb file  use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
478DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
479STEXI
480@item -fda @var{file}
481@itemx -fdb @var{file}
482@findex -fda
483@findex -fdb
484Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}).
485ETEXI
486
487DEF("hda", HAS_ARG, QEMU_OPTION_hda,
488    "-hda/-hdb file  use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
489DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
490DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
491    "-hdc/-hdd file  use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
492DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
493STEXI
494@item -hda @var{file}
495@itemx -hdb @var{file}
496@itemx -hdc @var{file}
497@itemx -hdd @var{file}
498@findex -hda
499@findex -hdb
500@findex -hdc
501@findex -hdd
502Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
503ETEXI
504
505DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
506    "-cdrom file     use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
507    QEMU_ARCH_ALL)
508STEXI
509@item -cdrom @var{file}
510@findex -cdrom
511Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
512@option{-cdrom} at the same time). You can use the host CD-ROM by
513using @file{/dev/cdrom} as filename (@pxref{host_drives}).
514ETEXI
515
516DEF("drive", HAS_ARG, QEMU_OPTION_drive,
517    "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
518    "       [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
519    "       [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
520    "       [,serial=s][,addr=A][,rerror=ignore|stop|report]\n"
521    "       [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n"
522    "       [,readonly=on|off][,copy-on-read=on|off]\n"
523    "       [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n"
524    "       [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n"
525    "       [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n"
526    "       [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n"
527    "       [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n"
528    "       [[,iops_size=is]]\n"
529    "       [[,group=g]]\n"
530    "                use 'file' as a drive image\n", QEMU_ARCH_ALL)
531STEXI
532@item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
533@findex -drive
534
535Define a new drive. Valid options are:
536
537@table @option
538@item file=@var{file}
539This option defines which disk image (@pxref{disk_images}) to use with
540this drive. If the filename contains comma, you must double it
541(for instance, "file=my,,file" to use file "my,file").
542
543Special files such as iSCSI devices can be specified using protocol
544specific URLs. See the section for "Device URL Syntax" for more information.
545@item if=@var{interface}
546This option defines on which type on interface the drive is connected.
547Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio.
548@item bus=@var{bus},unit=@var{unit}
549These options define where is connected the drive by defining the bus number and
550the unit id.
551@item index=@var{index}
552This option defines where is connected the drive by using an index in the list
553of available connectors of a given interface type.
554@item media=@var{media}
555This option defines the type of the media: disk or cdrom.
556@item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
557These options have the same definition as they have in @option{-hdachs}.
558@item snapshot=@var{snapshot}
559@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive
560(see @option{-snapshot}).
561@item cache=@var{cache}
562@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data.
563@item aio=@var{aio}
564@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
565@item discard=@var{discard}
566@var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls whether @dfn{discard} (also known as @dfn{trim} or @dfn{unmap}) requests are ignored or passed to the filesystem.  Some machine types may not support discard requests.
567@item format=@var{format}
568Specify which disk @var{format} will be used rather than detecting
569the format.  Can be used to specify format=raw to avoid interpreting
570an untrusted format header.
571@item serial=@var{serial}
572This option specifies the serial number to assign to the device.
573@item addr=@var{addr}
574Specify the controller's PCI address (if=virtio only).
575@item werror=@var{action},rerror=@var{action}
576Specify which @var{action} to take on write and read errors. Valid actions are:
577"ignore" (ignore the error and try to continue), "stop" (pause QEMU),
578"report" (report the error to the guest), "enospc" (pause QEMU only if the
579host disk is full; report the error to the guest otherwise).
580The default setting is @option{werror=enospc} and @option{rerror=report}.
581@item readonly
582Open drive @option{file} as read-only. Guest write attempts will fail.
583@item copy-on-read=@var{copy-on-read}
584@var{copy-on-read} is "on" or "off" and enables whether to copy read backing
585file sectors into the image file.
586@item detect-zeroes=@var{detect-zeroes}
587@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic
588conversion of plain zero writes by the OS to driver specific optimized
589zero write commands. You may even choose "unmap" if @var{discard} is set
590to "unmap" to allow a zero write to be converted to an UNMAP operation.
591@end table
592
593By default, the @option{cache=writeback} mode is used. It will report data
594writes as completed as soon as the data is present in the host page cache.
595This is safe as long as your guest OS makes sure to correctly flush disk caches
596where needed. If your guest OS does not handle volatile disk write caches
597correctly and your host crashes or loses power, then the guest may experience
598data corruption.
599
600For such guests, you should consider using @option{cache=writethrough}. This
601means that the host page cache will be used to read and write data, but write
602notification will be sent to the guest only after QEMU has made sure to flush
603each write to the disk. Be aware that this has a major impact on performance.
604
605The host page cache can be avoided entirely with @option{cache=none}.  This will
606attempt to do disk IO directly to the guest's memory.  QEMU may still perform
607an internal copy of the data. Note that this is considered a writeback mode and
608the guest OS must handle the disk write cache correctly in order to avoid data
609corruption on host crashes.
610
611The host page cache can be avoided while only sending write notifications to
612the guest when the data has been flushed to the disk using
613@option{cache=directsync}.
614
615In case you don't care about data integrity over host failures, use
616@option{cache=unsafe}. This option tells QEMU that it never needs to write any
617data to the disk but can instead keep things in cache. If anything goes wrong,
618like your host losing power, the disk storage getting disconnected accidentally,
619etc. your image will most probably be rendered unusable.   When using
620the @option{-snapshot} option, unsafe caching is always used.
621
622Copy-on-read avoids accessing the same backing file sectors repeatedly and is
623useful when the backing file is over a slow network.  By default copy-on-read
624is off.
625
626Instead of @option{-cdrom} you can use:
627@example
628qemu-system-i386 -drive file=file,index=2,media=cdrom
629@end example
630
631Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
632use:
633@example
634qemu-system-i386 -drive file=file,index=0,media=disk
635qemu-system-i386 -drive file=file,index=1,media=disk
636qemu-system-i386 -drive file=file,index=2,media=disk
637qemu-system-i386 -drive file=file,index=3,media=disk
638@end example
639
640You can open an image using pre-opened file descriptors from an fd set:
641@example
642qemu-system-i386
643-add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
644-add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
645-drive file=/dev/fdset/2,index=0,media=disk
646@end example
647
648You can connect a CDROM to the slave of ide0:
649@example
650qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
651@end example
652
653If you don't specify the "file=" argument, you define an empty drive:
654@example
655qemu-system-i386 -drive if=ide,index=1,media=cdrom
656@end example
657
658You can connect a SCSI disk with unit ID 6 on the bus #0:
659@example
660qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6
661@end example
662
663Instead of @option{-fda}, @option{-fdb}, you can use:
664@example
665qemu-system-i386 -drive file=file,index=0,if=floppy
666qemu-system-i386 -drive file=file,index=1,if=floppy
667@end example
668
669By default, @var{interface} is "ide" and @var{index} is automatically
670incremented:
671@example
672qemu-system-i386 -drive file=a -drive file=b"
673@end example
674is interpreted like:
675@example
676qemu-system-i386 -hda a -hdb b
677@end example
678ETEXI
679
680DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
681    "-mtdblock file  use 'file' as on-board Flash memory image\n",
682    QEMU_ARCH_ALL)
683STEXI
684@item -mtdblock @var{file}
685@findex -mtdblock
686Use @var{file} as on-board Flash memory image.
687ETEXI
688
689DEF("sd", HAS_ARG, QEMU_OPTION_sd,
690    "-sd file        use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL)
691STEXI
692@item -sd @var{file}
693@findex -sd
694Use @var{file} as SecureDigital card image.
695ETEXI
696
697DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
698    "-pflash file    use 'file' as a parallel flash image\n", QEMU_ARCH_ALL)
699STEXI
700@item -pflash @var{file}
701@findex -pflash
702Use @var{file} as a parallel flash image.
703ETEXI
704
705DEF("snapshot", 0, QEMU_OPTION_snapshot,
706    "-snapshot       write to temporary files instead of disk image files\n",
707    QEMU_ARCH_ALL)
708STEXI
709@item -snapshot
710@findex -snapshot
711Write to temporary files instead of disk image files. In this case,
712the raw disk image you use is not written back. You can however force
713the write back by pressing @key{C-a s} (@pxref{disk_images}).
714ETEXI
715
716DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
717    "-hdachs c,h,s[,t]\n" \
718    "                force hard disk 0 physical geometry and the optional BIOS\n" \
719    "                translation (t=none or lba) (usually QEMU can guess them)\n",
720    QEMU_ARCH_ALL)
721STEXI
722@item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
723@findex -hdachs
724Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
725@var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
726translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
727all those parameters. This option is useful for old MS-DOS disk
728images.
729ETEXI
730
731DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
732    "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
733    " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
734    QEMU_ARCH_ALL)
735
736STEXI
737
738@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}]
739@findex -fsdev
740Define a new file system device. Valid options are:
741@table @option
742@item @var{fsdriver}
743This option specifies the fs driver backend to use.
744Currently "local", "handle" and "proxy" file system drivers are supported.
745@item id=@var{id}
746Specifies identifier for this device
747@item path=@var{path}
748Specifies the export path for the file system device. Files under
749this path will be available to the 9p client on the guest.
750@item security_model=@var{security_model}
751Specifies the security model to be used for this export path.
752Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
753In "passthrough" security model, files are stored using the same
754credentials as they are created on the guest. This requires QEMU
755to run as root. In "mapped-xattr" security model, some of the file
756attributes like uid, gid, mode bits and link target are stored as
757file attributes. For "mapped-file" these attributes are stored in the
758hidden .virtfs_metadata directory. Directories exported by this security model cannot
759interact with other unix tools. "none" security model is same as
760passthrough except the sever won't report failures if it fails to
761set file attributes like ownership. Security model is mandatory
762only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
763security model as a parameter.
764@item writeout=@var{writeout}
765This is an optional argument. The only supported value is "immediate".
766This means that host page cache will be used to read and write data but
767write notification will be sent to the guest only when the data has been
768reported as written by the storage subsystem.
769@item readonly
770Enables exporting 9p share as a readonly mount for guests. By default
771read-write access is given.
772@item socket=@var{socket}
773Enables proxy filesystem driver to use passed socket file for communicating
774with virtfs-proxy-helper
775@item sock_fd=@var{sock_fd}
776Enables proxy filesystem driver to use passed socket descriptor for
777communicating with virtfs-proxy-helper. Usually a helper like libvirt
778will create socketpair and pass one of the fds as sock_fd
779@end table
780
781-fsdev option is used along with -device driver "virtio-9p-pci".
782@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
783Options for virtio-9p-pci driver are:
784@table @option
785@item fsdev=@var{id}
786Specifies the id value specified along with -fsdev option
787@item mount_tag=@var{mount_tag}
788Specifies the tag name to be used by the guest to mount this export point
789@end table
790
791ETEXI
792
793DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
794    "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
795    "        [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
796    QEMU_ARCH_ALL)
797
798STEXI
799
800@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}]
801@findex -virtfs
802
803The general form of a Virtual File system pass-through options are:
804@table @option
805@item @var{fsdriver}
806This option specifies the fs driver backend to use.
807Currently "local", "handle" and "proxy" file system drivers are supported.
808@item id=@var{id}
809Specifies identifier for this device
810@item path=@var{path}
811Specifies the export path for the file system device. Files under
812this path will be available to the 9p client on the guest.
813@item security_model=@var{security_model}
814Specifies the security model to be used for this export path.
815Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
816In "passthrough" security model, files are stored using the same
817credentials as they are created on the guest. This requires QEMU
818to run as root. In "mapped-xattr" security model, some of the file
819attributes like uid, gid, mode bits and link target are stored as
820file attributes. For "mapped-file" these attributes are stored in the
821hidden .virtfs_metadata directory. Directories exported by this security model cannot
822interact with other unix tools. "none" security model is same as
823passthrough except the sever won't report failures if it fails to
824set file attributes like ownership. Security model is mandatory only
825for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
826model as a parameter.
827@item writeout=@var{writeout}
828This is an optional argument. The only supported value is "immediate".
829This means that host page cache will be used to read and write data but
830write notification will be sent to the guest only when the data has been
831reported as written by the storage subsystem.
832@item readonly
833Enables exporting 9p share as a readonly mount for guests. By default
834read-write access is given.
835@item socket=@var{socket}
836Enables proxy filesystem driver to use passed socket file for
837communicating with virtfs-proxy-helper. Usually a helper like libvirt
838will create socketpair and pass one of the fds as sock_fd
839@item sock_fd
840Enables proxy filesystem driver to use passed 'sock_fd' as the socket
841descriptor for interfacing with virtfs-proxy-helper
842@end table
843ETEXI
844
845DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
846    "-virtfs_synth Create synthetic file system image\n",
847    QEMU_ARCH_ALL)
848STEXI
849@item -virtfs_synth
850@findex -virtfs_synth
851Create synthetic file system image
852ETEXI
853
854STEXI
855@end table
856ETEXI
857DEFHEADING()
858
859DEFHEADING(USB options)
860STEXI
861@table @option
862ETEXI
863
864DEF("usb", 0, QEMU_OPTION_usb,
865    "-usb            enable the USB driver (will be the default soon)\n",
866    QEMU_ARCH_ALL)
867STEXI
868@item -usb
869@findex -usb
870Enable the USB driver (will be the default soon)
871ETEXI
872
873DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
874    "-usbdevice name add the host or guest USB device 'name'\n",
875    QEMU_ARCH_ALL)
876STEXI
877
878@item -usbdevice @var{devname}
879@findex -usbdevice
880Add the USB device @var{devname}. @xref{usb_devices}.
881
882@table @option
883
884@item mouse
885Virtual Mouse. This will override the PS/2 mouse emulation when activated.
886
887@item tablet
888Pointer device that uses absolute coordinates (like a touchscreen). This
889means QEMU is able to report the mouse position without having to grab the
890mouse. Also overrides the PS/2 mouse emulation when activated.
891
892@item disk:[format=@var{format}]:@var{file}
893Mass storage device based on file. The optional @var{format} argument
894will be used rather than detecting the format. Can be used to specify
895@code{format=raw} to avoid interpreting an untrusted format header.
896
897@item host:@var{bus}.@var{addr}
898Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
899
900@item host:@var{vendor_id}:@var{product_id}
901Pass through the host device identified by @var{vendor_id}:@var{product_id}
902(Linux only).
903
904@item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
905Serial converter to host character device @var{dev}, see @code{-serial} for the
906available devices.
907
908@item braille
909Braille device.  This will use BrlAPI to display the braille output on a real
910or fake device.
911
912@item net:@var{options}
913Network adapter that supports CDC ethernet and RNDIS protocols.
914
915@end table
916ETEXI
917
918STEXI
919@end table
920ETEXI
921DEFHEADING()
922
923DEFHEADING(Display options)
924STEXI
925@table @option
926ETEXI
927
928DEF("display", HAS_ARG, QEMU_OPTION_display,
929    "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
930    "            [,window_close=on|off][,gl=on|off]|curses|none|\n"
931    "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n"
932    "-display vnc=<display>[,<optargs>]\n"
933    "-display curses\n"
934    "-display none"
935    "                select display type\n"
936    "The default display is equivalent to\n"
937#if defined(CONFIG_GTK)
938            "\t\"-display gtk\"\n"
939#elif defined(CONFIG_SDL)
940            "\t\"-display sdl\"\n"
941#elif defined(CONFIG_COCOA)
942            "\t\"-display cocoa\"\n"
943#elif defined(CONFIG_VNC)
944            "\t\"-vnc localhost:0,to=99,id=default\"\n"
945#else
946            "\t\"-display none\"\n"
947#endif
948    , QEMU_ARCH_ALL)
949STEXI
950@item -display @var{type}
951@findex -display
952Select type of display to use. This option is a replacement for the
953old style -sdl/-curses/... options. Valid values for @var{type} are
954@table @option
955@item sdl
956Display video output via SDL (usually in a separate graphics
957window; see the SDL documentation for other possibilities).
958@item curses
959Display video output via curses. For graphics device models which
960support a text mode, QEMU can display this output using a
961curses/ncurses interface. Nothing is displayed when the graphics
962device is in graphical mode or if the graphics device does not support
963a text mode. Generally only the VGA device models support text mode.
964@item none
965Do not display video output. The guest will still see an emulated
966graphics card, but its output will not be displayed to the QEMU
967user. This option differs from the -nographic option in that it
968only affects what is done with video output; -nographic also changes
969the destination of the serial and parallel port data.
970@item gtk
971Display video output in a GTK window. This interface provides drop-down
972menus and other UI elements to configure and control the VM during
973runtime.
974@item vnc
975Start a VNC server on display <arg>
976@end table
977ETEXI
978
979DEF("nographic", 0, QEMU_OPTION_nographic,
980    "-nographic      disable graphical output and redirect serial I/Os to console\n",
981    QEMU_ARCH_ALL)
982STEXI
983@item -nographic
984@findex -nographic
985Normally, if QEMU is compiled with graphical window support, it displays
986output such as guest graphics, guest console, and the QEMU monitor in a
987window. With this option, you can totally disable graphical output so
988that QEMU is a simple command line application. The emulated serial port
989is redirected on the console and muxed with the monitor (unless
990redirected elsewhere explicitly). Therefore, you can still use QEMU to
991debug a Linux kernel with a serial console. Use @key{C-a h} for help on
992switching between the console and monitor.
993ETEXI
994
995DEF("curses", 0, QEMU_OPTION_curses,
996    "-curses         shorthand for -display curses\n",
997    QEMU_ARCH_ALL)
998STEXI
999@item -curses
1000@findex -curses
1001Normally, if QEMU is compiled with graphical window support, it displays
1002output such as guest graphics, guest console, and the QEMU monitor in a
1003window. With this option, QEMU can display the VGA output when in text
1004mode using a curses/ncurses interface. Nothing is displayed in graphical
1005mode.
1006ETEXI
1007
1008DEF("no-frame", 0, QEMU_OPTION_no_frame,
1009    "-no-frame       open SDL window without a frame and window decorations\n",
1010    QEMU_ARCH_ALL)
1011STEXI
1012@item -no-frame
1013@findex -no-frame
1014Do not use decorations for SDL windows and start them using the whole
1015available screen space. This makes the using QEMU in a dedicated desktop
1016workspace more convenient.
1017ETEXI
1018
1019DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
1020    "-alt-grab       use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
1021    QEMU_ARCH_ALL)
1022STEXI
1023@item -alt-grab
1024@findex -alt-grab
1025Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
1026affects the special keys (for fullscreen, monitor-mode switching, etc).
1027ETEXI
1028
1029DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
1030    "-ctrl-grab      use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
1031    QEMU_ARCH_ALL)
1032STEXI
1033@item -ctrl-grab
1034@findex -ctrl-grab
1035Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
1036affects the special keys (for fullscreen, monitor-mode switching, etc).
1037ETEXI
1038
1039DEF("no-quit", 0, QEMU_OPTION_no_quit,
1040    "-no-quit        disable SDL window close capability\n", QEMU_ARCH_ALL)
1041STEXI
1042@item -no-quit
1043@findex -no-quit
1044Disable SDL window close capability.
1045ETEXI
1046
1047DEF("sdl", 0, QEMU_OPTION_sdl,
1048    "-sdl            shorthand for -display sdl\n", QEMU_ARCH_ALL)
1049STEXI
1050@item -sdl
1051@findex -sdl
1052Enable SDL.
1053ETEXI
1054
1055DEF("spice", HAS_ARG, QEMU_OPTION_spice,
1056    "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n"
1057    "       [,x509-key-file=<file>][,x509-key-password=<file>]\n"
1058    "       [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n"
1059    "       [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n"
1060    "       [,tls-ciphers=<list>]\n"
1061    "       [,tls-channel=[main|display|cursor|inputs|record|playback]]\n"
1062    "       [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n"
1063    "       [,sasl][,password=<secret>][,disable-ticketing]\n"
1064    "       [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n"
1065    "       [,jpeg-wan-compression=[auto|never|always]]\n"
1066    "       [,zlib-glz-wan-compression=[auto|never|always]]\n"
1067    "       [,streaming-video=[off|all|filter]][,disable-copy-paste]\n"
1068    "       [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n"
1069    "       [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n"
1070    "       [,gl=[on|off]]\n"
1071    "   enable spice\n"
1072    "   at least one of {port, tls-port} is mandatory\n",
1073    QEMU_ARCH_ALL)
1074STEXI
1075@item -spice @var{option}[,@var{option}[,...]]
1076@findex -spice
1077Enable the spice remote desktop protocol. Valid options are
1078
1079@table @option
1080
1081@item port=<nr>
1082Set the TCP port spice is listening on for plaintext channels.
1083
1084@item addr=<addr>
1085Set the IP address spice is listening on.  Default is any address.
1086
1087@item ipv4
1088@itemx ipv6
1089@itemx unix
1090Force using the specified IP version.
1091
1092@item password=<secret>
1093Set the password you need to authenticate.
1094
1095@item sasl
1096Require that the client use SASL to authenticate with the spice.
1097The exact choice of authentication method used is controlled from the
1098system / user's SASL configuration file for the 'qemu' service. This
1099is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1100unprivileged user, an environment variable SASL_CONF_PATH can be used
1101to make it search alternate locations for the service config.
1102While some SASL auth methods can also provide data encryption (eg GSSAPI),
1103it is recommended that SASL always be combined with the 'tls' and
1104'x509' settings to enable use of SSL and server certificates. This
1105ensures a data encryption preventing compromise of authentication
1106credentials.
1107
1108@item disable-ticketing
1109Allow client connects without authentication.
1110
1111@item disable-copy-paste
1112Disable copy paste between the client and the guest.
1113
1114@item disable-agent-file-xfer
1115Disable spice-vdagent based file-xfer between the client and the guest.
1116
1117@item tls-port=<nr>
1118Set the TCP port spice is listening on for encrypted channels.
1119
1120@item x509-dir=<dir>
1121Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1122
1123@item x509-key-file=<file>
1124@itemx x509-key-password=<file>
1125@itemx x509-cert-file=<file>
1126@itemx x509-cacert-file=<file>
1127@itemx x509-dh-key-file=<file>
1128The x509 file names can also be configured individually.
1129
1130@item tls-ciphers=<list>
1131Specify which ciphers to use.
1132
1133@item tls-channel=[main|display|cursor|inputs|record|playback]
1134@itemx plaintext-channel=[main|display|cursor|inputs|record|playback]
1135Force specific channel to be used with or without TLS encryption.  The
1136options can be specified multiple times to configure multiple
1137channels.  The special name "default" can be used to set the default
1138mode.  For channels which are not explicitly forced into one mode the
1139spice client is allowed to pick tls/plaintext as he pleases.
1140
1141@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1142Configure image compression (lossless).
1143Default is auto_glz.
1144
1145@item jpeg-wan-compression=[auto|never|always]
1146@itemx zlib-glz-wan-compression=[auto|never|always]
1147Configure wan image compression (lossy for slow links).
1148Default is auto.
1149
1150@item streaming-video=[off|all|filter]
1151Configure video stream detection.  Default is off.
1152
1153@item agent-mouse=[on|off]
1154Enable/disable passing mouse events via vdagent.  Default is on.
1155
1156@item playback-compression=[on|off]
1157Enable/disable audio stream compression (using celt 0.5.1).  Default is on.
1158
1159@item seamless-migration=[on|off]
1160Enable/disable spice seamless migration. Default is off.
1161
1162@item gl=[on|off]
1163Enable/disable OpenGL context. Default is off.
1164
1165@end table
1166ETEXI
1167
1168DEF("portrait", 0, QEMU_OPTION_portrait,
1169    "-portrait       rotate graphical output 90 deg left (only PXA LCD)\n",
1170    QEMU_ARCH_ALL)
1171STEXI
1172@item -portrait
1173@findex -portrait
1174Rotate graphical output 90 deg left (only PXA LCD).
1175ETEXI
1176
1177DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
1178    "-rotate <deg>   rotate graphical output some deg left (only PXA LCD)\n",
1179    QEMU_ARCH_ALL)
1180STEXI
1181@item -rotate @var{deg}
1182@findex -rotate
1183Rotate graphical output some deg left (only PXA LCD).
1184ETEXI
1185
1186DEF("vga", HAS_ARG, QEMU_OPTION_vga,
1187    "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n"
1188    "                select video card type\n", QEMU_ARCH_ALL)
1189STEXI
1190@item -vga @var{type}
1191@findex -vga
1192Select type of VGA card to emulate. Valid values for @var{type} are
1193@table @option
1194@item cirrus
1195Cirrus Logic GD5446 Video card. All Windows versions starting from
1196Windows 95 should recognize and use this graphic card. For optimal
1197performances, use 16 bit color depth in the guest and the host OS.
1198(This one is the default)
1199@item std
1200Standard VGA card with Bochs VBE extensions.  If your guest OS
1201supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1202to use high resolution modes (>= 1280x1024x16) then you should use
1203this option.
1204@item vmware
1205VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1206recent XFree86/XOrg server or Windows guest with a driver for this
1207card.
1208@item qxl
1209QXL paravirtual graphic card.  It is VGA compatible (including VESA
12102.0 VBE support).  Works best with qxl guest drivers installed though.
1211Recommended choice when using the spice protocol.
1212@item tcx
1213(sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1214sun4m machines and offers both 8-bit and 24-bit colour depths at a
1215fixed resolution of 1024x768.
1216@item cg3
1217(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1218for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1219resolutions aimed at people wishing to run older Solaris versions.
1220@item virtio
1221Virtio VGA card.
1222@item none
1223Disable VGA card.
1224@end table
1225ETEXI
1226
1227DEF("full-screen", 0, QEMU_OPTION_full_screen,
1228    "-full-screen    start in full screen\n", QEMU_ARCH_ALL)
1229STEXI
1230@item -full-screen
1231@findex -full-screen
1232Start in full screen.
1233ETEXI
1234
1235DEF("g", 1, QEMU_OPTION_g ,
1236    "-g WxH[xDEPTH]  Set the initial graphical resolution and depth\n",
1237    QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1238STEXI
1239@item -g @var{width}x@var{height}[x@var{depth}]
1240@findex -g
1241Set the initial graphical resolution and depth (PPC, SPARC only).
1242ETEXI
1243
1244DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
1245    "-vnc <display>  shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL)
1246STEXI
1247@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1248@findex -vnc
1249Normally, if QEMU is compiled with graphical window support, it displays
1250output such as guest graphics, guest console, and the QEMU monitor in a
1251window. With this option, you can have QEMU listen on VNC display
1252@var{display} and redirect the VGA display over the VNC session. It is
1253very useful to enable the usb tablet device when using this option
1254(option @option{-usbdevice tablet}). When using the VNC display, you
1255must use the @option{-k} parameter to set the keyboard layout if you are
1256not using en-us. Valid syntax for the @var{display} is
1257
1258@table @option
1259
1260@item to=@var{L}
1261
1262With this option, QEMU will try next available VNC @var{display}s, until the
1263number @var{L}, if the origianlly defined "-vnc @var{display}" is not
1264available, e.g. port 5900+@var{display} is already used by another
1265application. By default, to=0.
1266
1267@item @var{host}:@var{d}
1268
1269TCP connections will only be allowed from @var{host} on display @var{d}.
1270By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1271be omitted in which case the server will accept connections from any host.
1272
1273@item unix:@var{path}
1274
1275Connections will be allowed over UNIX domain sockets where @var{path} is the
1276location of a unix socket to listen for connections on.
1277
1278@item none
1279
1280VNC is initialized but not started. The monitor @code{change} command
1281can be used to later start the VNC server.
1282
1283@end table
1284
1285Following the @var{display} value there may be one or more @var{option} flags
1286separated by commas. Valid options are
1287
1288@table @option
1289
1290@item reverse
1291
1292Connect to a listening VNC client via a ``reverse'' connection. The
1293client is specified by the @var{display}. For reverse network
1294connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1295is a TCP port number, not a display number.
1296
1297@item websocket
1298
1299Opens an additional TCP listening port dedicated to VNC Websocket connections.
1300By definition the Websocket port is 5700+@var{display}. If @var{host} is
1301specified connections will only be allowed from this host.
1302As an alternative the Websocket port could be specified by using
1303@code{websocket}=@var{port}.
1304If no TLS credentials are provided, the websocket connection runs in
1305unencrypted mode. If TLS credentials are provided, the websocket connection
1306requires encrypted client connections.
1307
1308@item password
1309
1310Require that password based authentication is used for client connections.
1311
1312The password must be set separately using the @code{set_password} command in
1313the @ref{pcsys_monitor}. The syntax to change your password is:
1314@code{set_password <protocol> <password>} where <protocol> could be either
1315"vnc" or "spice".
1316
1317If you would like to change <protocol> password expiration, you should use
1318@code{expire_password <protocol> <expiration-time>} where expiration time could
1319be one of the following options: now, never, +seconds or UNIX time of
1320expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1321to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1322date and time).
1323
1324You can also use keywords "now" or "never" for the expiration time to
1325allow <protocol> password to expire immediately or never expire.
1326
1327@item tls-creds=@var{ID}
1328
1329Provides the ID of a set of TLS credentials to use to secure the
1330VNC server. They will apply to both the normal VNC server socket
1331and the websocket socket (if enabled). Setting TLS credentials
1332will cause the VNC server socket to enable the VeNCrypt auth
1333mechanism.  The credentials should have been previously created
1334using the @option{-object tls-creds} argument.
1335
1336The @option{tls-creds} parameter obsoletes the @option{tls},
1337@option{x509}, and @option{x509verify} options, and as such
1338it is not permitted to set both new and old type options at
1339the same time.
1340
1341@item tls
1342
1343Require that client use TLS when communicating with the VNC server. This
1344uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1345attack. It is recommended that this option be combined with either the
1346@option{x509} or @option{x509verify} options.
1347
1348This option is now deprecated in favor of using the @option{tls-creds}
1349argument.
1350
1351@item x509=@var{/path/to/certificate/dir}
1352
1353Valid if @option{tls} is specified. Require that x509 credentials are used
1354for negotiating the TLS session. The server will send its x509 certificate
1355to the client. It is recommended that a password be set on the VNC server
1356to provide authentication of the client when this is used. The path following
1357this option specifies where the x509 certificates are to be loaded from.
1358See the @ref{vnc_security} section for details on generating certificates.
1359
1360This option is now deprecated in favour of using the @option{tls-creds}
1361argument.
1362
1363@item x509verify=@var{/path/to/certificate/dir}
1364
1365Valid if @option{tls} is specified. Require that x509 credentials are used
1366for negotiating the TLS session. The server will send its x509 certificate
1367to the client, and request that the client send its own x509 certificate.
1368The server will validate the client's certificate against the CA certificate,
1369and reject clients when validation fails. If the certificate authority is
1370trusted, this is a sufficient authentication mechanism. You may still wish
1371to set a password on the VNC server as a second authentication layer. The
1372path following this option specifies where the x509 certificates are to
1373be loaded from. See the @ref{vnc_security} section for details on generating
1374certificates.
1375
1376This option is now deprecated in favour of using the @option{tls-creds}
1377argument.
1378
1379@item sasl
1380
1381Require that the client use SASL to authenticate with the VNC server.
1382The exact choice of authentication method used is controlled from the
1383system / user's SASL configuration file for the 'qemu' service. This
1384is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1385unprivileged user, an environment variable SASL_CONF_PATH can be used
1386to make it search alternate locations for the service config.
1387While some SASL auth methods can also provide data encryption (eg GSSAPI),
1388it is recommended that SASL always be combined with the 'tls' and
1389'x509' settings to enable use of SSL and server certificates. This
1390ensures a data encryption preventing compromise of authentication
1391credentials. See the @ref{vnc_security} section for details on using
1392SASL authentication.
1393
1394@item acl
1395
1396Turn on access control lists for checking of the x509 client certificate
1397and SASL party. For x509 certs, the ACL check is made against the
1398certificate's distinguished name. This is something that looks like
1399@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1400made against the username, which depending on the SASL plugin, may
1401include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1402When the @option{acl} flag is set, the initial access list will be
1403empty, with a @code{deny} policy. Thus no one will be allowed to
1404use the VNC server until the ACLs have been loaded. This can be
1405achieved using the @code{acl} monitor command.
1406
1407@item lossy
1408
1409Enable lossy compression methods (gradient, JPEG, ...). If this
1410option is set, VNC client may receive lossy framebuffer updates
1411depending on its encoding settings. Enabling this option can save
1412a lot of bandwidth at the expense of quality.
1413
1414@item non-adaptive
1415
1416Disable adaptive encodings. Adaptive encodings are enabled by default.
1417An adaptive encoding will try to detect frequently updated screen regions,
1418and send updates in these regions using a lossy encoding (like JPEG).
1419This can be really helpful to save bandwidth when playing videos. Disabling
1420adaptive encodings restores the original static behavior of encodings
1421like Tight.
1422
1423@item share=[allow-exclusive|force-shared|ignore]
1424
1425Set display sharing policy.  'allow-exclusive' allows clients to ask
1426for exclusive access.  As suggested by the rfb spec this is
1427implemented by dropping other connections.  Connecting multiple
1428clients in parallel requires all clients asking for a shared session
1429(vncviewer: -shared switch).  This is the default.  'force-shared'
1430disables exclusive client access.  Useful for shared desktop sessions,
1431where you don't want someone forgetting specify -shared disconnect
1432everybody else.  'ignore' completely ignores the shared flag and
1433allows everybody connect unconditionally.  Doesn't conform to the rfb
1434spec but is traditional QEMU behavior.
1435
1436@item key-delay-ms
1437
1438Set keyboard delay, for key down and key up events, in milliseconds.
1439Default is 1.  Keyboards are low-bandwidth devices, so this slowdown
1440can help the device and guest to keep up and not lose events in case
1441events are arriving in bulk.  Possible causes for the latter are flaky
1442network connections, or scripts for automated testing.
1443
1444@end table
1445ETEXI
1446
1447STEXI
1448@end table
1449ETEXI
1450ARCHHEADING(, QEMU_ARCH_I386)
1451
1452ARCHHEADING(i386 target only, QEMU_ARCH_I386)
1453STEXI
1454@table @option
1455ETEXI
1456
1457DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1458    "-win2k-hack     use it when installing Windows 2000 to avoid a disk full bug\n",
1459    QEMU_ARCH_I386)
1460STEXI
1461@item -win2k-hack
1462@findex -win2k-hack
1463Use it when installing Windows 2000 to avoid a disk full bug. After
1464Windows 2000 is installed, you no longer need this option (this option
1465slows down the IDE transfers).
1466ETEXI
1467
1468HXCOMM Deprecated by -rtc
1469DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1470
1471DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1472    "-no-fd-bootchk  disable boot signature checking for floppy disks\n",
1473    QEMU_ARCH_I386)
1474STEXI
1475@item -no-fd-bootchk
1476@findex -no-fd-bootchk
1477Disable boot signature checking for floppy disks in BIOS. May
1478be needed to boot from old floppy disks.
1479ETEXI
1480
1481DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1482           "-no-acpi        disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1483STEXI
1484@item -no-acpi
1485@findex -no-acpi
1486Disable ACPI (Advanced Configuration and Power Interface) support. Use
1487it if your guest OS complains about ACPI problems (PC target machine
1488only).
1489ETEXI
1490
1491DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1492    "-no-hpet        disable HPET\n", QEMU_ARCH_I386)
1493STEXI
1494@item -no-hpet
1495@findex -no-hpet
1496Disable HPET support.
1497ETEXI
1498
1499DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1500    "-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"
1501    "                ACPI table description\n", QEMU_ARCH_I386)
1502STEXI
1503@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}]...]
1504@findex -acpitable
1505Add ACPI table with specified header fields and context from specified files.
1506For file=, take whole ACPI table from the specified files, including all
1507ACPI headers (possible overridden by other options).
1508For data=, only data
1509portion of the table is used, all header information is specified in the
1510command line.
1511If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id
1512fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order
1513to ensure the field matches required by the Microsoft SLIC spec and the ACPI
1514spec.
1515ETEXI
1516
1517DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1518    "-smbios file=binary\n"
1519    "                load SMBIOS entry from binary file\n"
1520    "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1521    "              [,uefi=on|off]\n"
1522    "                specify SMBIOS type 0 fields\n"
1523    "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1524    "              [,uuid=uuid][,sku=str][,family=str]\n"
1525    "                specify SMBIOS type 1 fields\n"
1526    "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1527    "              [,asset=str][,location=str]\n"
1528    "                specify SMBIOS type 2 fields\n"
1529    "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n"
1530    "              [,sku=str]\n"
1531    "                specify SMBIOS type 3 fields\n"
1532    "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n"
1533    "              [,asset=str][,part=str]\n"
1534    "                specify SMBIOS type 4 fields\n"
1535    "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n"
1536    "               [,asset=str][,part=str][,speed=%d]\n"
1537    "                specify SMBIOS type 17 fields\n",
1538    QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1539STEXI
1540@item -smbios file=@var{binary}
1541@findex -smbios
1542Load SMBIOS entry from binary file.
1543
1544@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1545Specify SMBIOS type 0 fields
1546
1547@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}]
1548Specify SMBIOS type 1 fields
1549
1550@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}]
1551Specify SMBIOS type 2 fields
1552
1553@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}]
1554Specify SMBIOS type 3 fields
1555
1556@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}]
1557Specify SMBIOS type 4 fields
1558
1559@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}]
1560Specify SMBIOS type 17 fields
1561ETEXI
1562
1563STEXI
1564@end table
1565ETEXI
1566DEFHEADING()
1567
1568DEFHEADING(Network options)
1569STEXI
1570@table @option
1571ETEXI
1572
1573HXCOMM Legacy slirp options (now moved to -net user):
1574#ifdef CONFIG_SLIRP
1575DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1576DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1577DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1578#ifndef _WIN32
1579DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1580#endif
1581#endif
1582
1583DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1584#ifdef CONFIG_SLIRP
1585    "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n"
1586    "         [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n"
1587    "         [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n"
1588    "         [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,tftp=dir]\n"
1589    "         [,bootfile=f][,hostfwd=rule][,guestfwd=rule]"
1590#ifndef _WIN32
1591                                             "[,smb=dir[,smbserver=addr]]\n"
1592#endif
1593    "                configure a user mode network backend with ID 'str',\n"
1594    "                its DHCP server and optional services\n"
1595#endif
1596#ifdef _WIN32
1597    "-netdev tap,id=str,ifname=name\n"
1598    "                configure a host TAP network backend with ID 'str'\n"
1599#else
1600    "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n"
1601    "         [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n"
1602    "         [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n"
1603    "         [,poll-us=n]\n"
1604    "                configure a host TAP network backend with ID 'str'\n"
1605    "                connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1606    "                use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1607    "                to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1608    "                to deconfigure it\n"
1609    "                use '[down]script=no' to disable script execution\n"
1610    "                use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1611    "                configure it\n"
1612    "                use 'fd=h' to connect to an already opened TAP interface\n"
1613    "                use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n"
1614    "                use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
1615    "                default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
1616    "                use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1617    "                use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1618    "                use vhost=on to enable experimental in kernel accelerator\n"
1619    "                    (only has effect for virtio guests which use MSIX)\n"
1620    "                use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1621    "                use 'vhostfd=h' to connect to an already opened vhost net device\n"
1622    "                use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n"
1623    "                use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n"
1624    "                use 'poll-us=n' to speciy the maximum number of microseconds that could be\n"
1625    "                spent on busy polling for vhost net\n"
1626    "-netdev bridge,id=str[,br=bridge][,helper=helper]\n"
1627    "                configure a host TAP network backend with ID 'str' that is\n"
1628    "                connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n"
1629    "                using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n"
1630#endif
1631#ifdef __linux__
1632    "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n"
1633    "         [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n"
1634    "         [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n"
1635    "         [,rxcookie=rxcookie][,offset=offset]\n"
1636    "                configure a network backend with ID 'str' connected to\n"
1637    "                an Ethernet over L2TPv3 pseudowire.\n"
1638    "                Linux kernel 3.3+ as well as most routers can talk\n"
1639    "                L2TPv3. This transport allows connecting a VM to a VM,\n"
1640    "                VM to a router and even VM to Host. It is a nearly-universal\n"
1641    "                standard (RFC3391). Note - this implementation uses static\n"
1642    "                pre-configured tunnels (same as the Linux kernel).\n"
1643    "                use 'src=' to specify source address\n"
1644    "                use 'dst=' to specify destination address\n"
1645    "                use 'udp=on' to specify udp encapsulation\n"
1646    "                use 'srcport=' to specify source udp port\n"
1647    "                use 'dstport=' to specify destination udp port\n"
1648    "                use 'ipv6=on' to force v6\n"
1649    "                L2TPv3 uses cookies to prevent misconfiguration as\n"
1650    "                well as a weak security measure\n"
1651    "                use 'rxcookie=0x012345678' to specify a rxcookie\n"
1652    "                use 'txcookie=0x012345678' to specify a txcookie\n"
1653    "                use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n"
1654    "                use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n"
1655    "                use 'pincounter=on' to work around broken counter handling in peer\n"
1656    "                use 'offset=X' to add an extra offset between header and data\n"
1657#endif
1658    "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n"
1659    "                configure a network backend to connect to another network\n"
1660    "                using a socket connection\n"
1661    "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1662    "                configure a network backend to connect to a multicast maddr and port\n"
1663    "                use 'localaddr=addr' to specify the host address to send packets from\n"
1664    "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
1665    "                configure a network backend to connect to another network\n"
1666    "                using an UDP tunnel\n"
1667#ifdef CONFIG_VDE
1668    "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1669    "                configure a network backend to connect to port 'n' of a vde switch\n"
1670    "                running on host and listening for incoming connections on 'socketpath'.\n"
1671    "                Use group 'groupname' and mode 'octalmode' to change default\n"
1672    "                ownership and permissions for communication port.\n"
1673#endif
1674#ifdef CONFIG_NETMAP
1675    "-netdev netmap,id=str,ifname=name[,devname=nmname]\n"
1676    "                attach to the existing netmap-enabled network interface 'name', or to a\n"
1677    "                VALE port (created on the fly) called 'name' ('nmname' is name of the \n"
1678    "                netmap device, defaults to '/dev/netmap')\n"
1679#endif
1680    "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n"
1681    "                configure a vhost-user network, backed by a chardev 'dev'\n"
1682    "-netdev hubport,id=str,hubid=n\n"
1683    "                configure a hub port on QEMU VLAN 'n'\n", QEMU_ARCH_ALL)
1684DEF("net", HAS_ARG, QEMU_OPTION_net,
1685    "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
1686    "                old way to create a new NIC and connect it to VLAN 'n'\n"
1687    "                (use the '-device devtype,netdev=str' option if possible instead)\n"
1688    "-net dump[,vlan=n][,file=f][,len=n]\n"
1689    "                dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n"
1690    "-net none       use it alone to have zero network devices. If no -net option\n"
1691    "                is provided, the default is '-net nic -net user'\n"
1692    "-net ["
1693#ifdef CONFIG_SLIRP
1694    "user|"
1695#endif
1696    "tap|"
1697    "bridge|"
1698#ifdef CONFIG_VDE
1699    "vde|"
1700#endif
1701#ifdef CONFIG_NETMAP
1702    "netmap|"
1703#endif
1704    "socket][,vlan=n][,option][,option][,...]\n"
1705    "                old way to initialize a host network interface\n"
1706    "                (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL)
1707STEXI
1708@item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1709@findex -net
1710Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1711= 0 is the default). The NIC is an e1000 by default on the PC
1712target. Optionally, the MAC address can be changed to @var{mac}, the
1713device address set to @var{addr} (PCI cards only),
1714and a @var{name} can be assigned for use in monitor commands.
1715Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1716that the card should have; this option currently only affects virtio cards; set
1717@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1718NIC is created.  QEMU can emulate several different models of network card.
1719Valid values for @var{type} are
1720@code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1721@code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1722@code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1723Not all devices are supported on all targets.  Use @code{-net nic,model=help}
1724for a list of available devices for your target.
1725
1726@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
1727@findex -netdev
1728@item -net user[,@var{option}][,@var{option}][,...]
1729Use the user mode network stack which requires no administrator
1730privilege to run. Valid options are:
1731
1732@table @option
1733@item vlan=@var{n}
1734Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1735
1736@item id=@var{id}
1737@itemx name=@var{name}
1738Assign symbolic name for use in monitor commands.
1739
1740@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must
1741be enabled.  If neither is specified both protocols are enabled.
1742
1743@item net=@var{addr}[/@var{mask}]
1744Set IP network address the guest will see. Optionally specify the netmask,
1745either in the form a.b.c.d or as number of valid top-most bits. Default is
174610.0.2.0/24.
1747
1748@item host=@var{addr}
1749Specify the guest-visible address of the host. Default is the 2nd IP in the
1750guest network, i.e. x.x.x.2.
1751
1752@item ipv6-net=@var{addr}[/@var{int}]
1753Set IPv6 network address the guest will see (default is fec0::/64). The
1754network prefix is given in the usual hexadecimal IPv6 address
1755notation. The prefix size is optional, and is given as the number of
1756valid top-most bits (default is 64).
1757
1758@item ipv6-host=@var{addr}
1759Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in
1760the guest network, i.e. xxxx::2.
1761
1762@item restrict=on|off
1763If this option is enabled, the guest will be isolated, i.e. it will not be
1764able to contact the host and no guest IP packets will be routed over the host
1765to the outside. This option does not affect any explicitly set forwarding rules.
1766
1767@item hostname=@var{name}
1768Specifies the client hostname reported by the built-in DHCP server.
1769
1770@item dhcpstart=@var{addr}
1771Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1772is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1773
1774@item dns=@var{addr}
1775Specify the guest-visible address of the virtual nameserver. The address must
1776be different from the host address. Default is the 3rd IP in the guest network,
1777i.e. x.x.x.3.
1778
1779@item ipv6-dns=@var{addr}
1780Specify the guest-visible address of the IPv6 virtual nameserver. The address
1781must be different from the host address. Default is the 3rd IP in the guest
1782network, i.e. xxxx::3.
1783
1784@item dnssearch=@var{domain}
1785Provides an entry for the domain-search list sent by the built-in
1786DHCP server. More than one domain suffix can be transmitted by specifying
1787this option multiple times. If supported, this will cause the guest to
1788automatically try to append the given domain suffix(es) in case a domain name
1789can not be resolved.
1790
1791Example:
1792@example
1793qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
1794@end example
1795
1796@item tftp=@var{dir}
1797When using the user mode network stack, activate a built-in TFTP
1798server. The files in @var{dir} will be exposed as the root of a TFTP server.
1799The TFTP client on the guest must be configured in binary mode (use the command
1800@code{bin} of the Unix TFTP client).
1801
1802@item bootfile=@var{file}
1803When using the user mode network stack, broadcast @var{file} as the BOOTP
1804filename. In conjunction with @option{tftp}, this can be used to network boot
1805a guest from a local directory.
1806
1807Example (using pxelinux):
1808@example
1809qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1810@end example
1811
1812@item smb=@var{dir}[,smbserver=@var{addr}]
1813When using the user mode network stack, activate a built-in SMB
1814server so that Windows OSes can access to the host files in @file{@var{dir}}
1815transparently. The IP address of the SMB server can be set to @var{addr}. By
1816default the 4th IP in the guest network is used, i.e. x.x.x.4.
1817
1818In the guest Windows OS, the line:
1819@example
182010.0.2.4 smbserver
1821@end example
1822must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1823or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1824
1825Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
1826
1827Note that a SAMBA server must be installed on the host OS.
1828QEMU was tested successfully with smbd versions from Red Hat 9,
1829Fedora Core 3 and OpenSUSE 11.x.
1830
1831@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1832Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1833the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1834@var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1835given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1836be bound to a specific host interface. If no connection type is set, TCP is
1837used. This option can be given multiple times.
1838
1839For example, to redirect host X11 connection from screen 1 to guest
1840screen 0, use the following:
1841
1842@example
1843# on the host
1844qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1845# this host xterm should open in the guest X11 server
1846xterm -display :1
1847@end example
1848
1849To redirect telnet connections from host port 5555 to telnet port on
1850the guest, use the following:
1851
1852@example
1853# on the host
1854qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
1855telnet localhost 5555
1856@end example
1857
1858Then when you use on the host @code{telnet localhost 5555}, you
1859connect to the guest telnet server.
1860
1861@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1862@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
1863Forward guest TCP connections to the IP address @var{server} on port @var{port}
1864to the character device @var{dev} or to a program executed by @var{cmd:command}
1865which gets spawned for each connection. This option can be given multiple times.
1866
1867You can either use a chardev directly and have that one used throughout QEMU's
1868lifetime, like in the following example:
1869
1870@example
1871# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
1872# the guest accesses it
1873qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...]
1874@end example
1875
1876Or you can execute a command on every TCP connection established by the guest,
1877so that QEMU behaves similar to an inetd process for that virtual server:
1878
1879@example
1880# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
1881# and connect the TCP stream to its stdin/stdout
1882qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
1883@end example
1884
1885@end table
1886
1887Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
1888processed and applied to -net user. Mixing them with the new configuration
1889syntax gives undefined results. Their use for new applications is discouraged
1890as they will be removed from future versions.
1891
1892@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}]
1893@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}]
1894Connect the host TAP network interface @var{name} to VLAN @var{n}.
1895
1896Use the network script @var{file} to configure it and the network script
1897@var{dfile} to deconfigure it. If @var{name} is not provided, the OS
1898automatically provides one. The default network configure script is
1899@file{/etc/qemu-ifup} and the default network deconfigure script is
1900@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
1901to disable script execution.
1902
1903If running QEMU as an unprivileged user, use the network helper
1904@var{helper} to configure the TAP interface and attach it to the bridge.
1905The default network helper executable is @file{/path/to/qemu-bridge-helper}
1906and the default bridge device is @file{br0}.
1907
1908@option{fd}=@var{h} can be used to specify the handle of an already
1909opened host TAP interface.
1910
1911Examples:
1912
1913@example
1914#launch a QEMU instance with the default network script
1915qemu-system-i386 linux.img -net nic -net tap
1916@end example
1917
1918@example
1919#launch a QEMU instance with two NICs, each one connected
1920#to a TAP device
1921qemu-system-i386 linux.img \
1922                 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
1923                 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
1924@end example
1925
1926@example
1927#launch a QEMU instance with the default network helper to
1928#connect a TAP device to bridge br0
1929qemu-system-i386 linux.img \
1930                 -net nic -net tap,"helper=/path/to/qemu-bridge-helper"
1931@end example
1932
1933@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
1934@itemx -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
1935Connect a host TAP network interface to a host bridge device.
1936
1937Use the network helper @var{helper} to configure the TAP interface and
1938attach it to the bridge. The default network helper executable is
1939@file{/path/to/qemu-bridge-helper} and the default bridge
1940device is @file{br0}.
1941
1942Examples:
1943
1944@example
1945#launch a QEMU instance with the default network helper to
1946#connect a TAP device to bridge br0
1947qemu-system-i386 linux.img -net bridge -net nic,model=virtio
1948@end example
1949
1950@example
1951#launch a QEMU instance with the default network helper to
1952#connect a TAP device to bridge qemubr0
1953qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
1954@end example
1955
1956@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1957@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1958
1959Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
1960machine using a TCP socket connection. If @option{listen} is
1961specified, QEMU waits for incoming connections on @var{port}
1962(@var{host} is optional). @option{connect} is used to connect to
1963another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
1964specifies an already opened TCP socket.
1965
1966Example:
1967@example
1968# launch a first QEMU instance
1969qemu-system-i386 linux.img \
1970                 -net nic,macaddr=52:54:00:12:34:56 \
1971                 -net socket,listen=:1234
1972# connect the VLAN 0 of this instance to the VLAN 0
1973# of the first instance
1974qemu-system-i386 linux.img \
1975                 -net nic,macaddr=52:54:00:12:34:57 \
1976                 -net socket,connect=127.0.0.1:1234
1977@end example
1978
1979@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1980@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1981
1982Create a VLAN @var{n} shared with another QEMU virtual
1983machines using a UDP multicast socket, effectively making a bus for
1984every QEMU with same multicast address @var{maddr} and @var{port}.
1985NOTES:
1986@enumerate
1987@item
1988Several QEMU can be running on different hosts and share same bus (assuming
1989correct multicast setup for these hosts).
1990@item
1991mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
1992@url{http://user-mode-linux.sf.net}.
1993@item
1994Use @option{fd=h} to specify an already opened UDP multicast socket.
1995@end enumerate
1996
1997Example:
1998@example
1999# launch one QEMU instance
2000qemu-system-i386 linux.img \
2001                 -net nic,macaddr=52:54:00:12:34:56 \
2002                 -net socket,mcast=230.0.0.1:1234
2003# launch another QEMU instance on same "bus"
2004qemu-system-i386 linux.img \
2005                 -net nic,macaddr=52:54:00:12:34:57 \
2006                 -net socket,mcast=230.0.0.1:1234
2007# launch yet another QEMU instance on same "bus"
2008qemu-system-i386 linux.img \
2009                 -net nic,macaddr=52:54:00:12:34:58 \
2010                 -net socket,mcast=230.0.0.1:1234
2011@end example
2012
2013Example (User Mode Linux compat.):
2014@example
2015# launch QEMU instance (note mcast address selected
2016# is UML's default)
2017qemu-system-i386 linux.img \
2018                 -net nic,macaddr=52:54:00:12:34:56 \
2019                 -net socket,mcast=239.192.168.1:1102
2020# launch UML
2021/path/to/linux ubd0=/path/to/root_fs eth0=mcast
2022@end example
2023
2024Example (send packets from host's 1.2.3.4):
2025@example
2026qemu-system-i386 linux.img \
2027                 -net nic,macaddr=52:54:00:12:34:56 \
2028                 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
2029@end example
2030
2031@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}]
2032@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}]
2033Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular
2034protocol to transport Ethernet (and other Layer 2) data frames between
2035two systems. It is present in routers, firewalls and the Linux kernel
2036(from version 3.3 onwards).
2037
2038This transport allows a VM to communicate to another VM, router or firewall directly.
2039
2040@item src=@var{srcaddr}
2041    source address (mandatory)
2042@item dst=@var{dstaddr}
2043    destination address (mandatory)
2044@item udp
2045    select udp encapsulation (default is ip).
2046@item srcport=@var{srcport}
2047    source udp port.
2048@item dstport=@var{dstport}
2049    destination udp port.
2050@item ipv6
2051    force v6, otherwise defaults to v4.
2052@item rxcookie=@var{rxcookie}
2053@itemx txcookie=@var{txcookie}
2054    Cookies are a weak form of security in the l2tpv3 specification.
2055Their function is mostly to prevent misconfiguration. By default they are 32
2056bit.
2057@item cookie64
2058    Set cookie size to 64 bit instead of the default 32
2059@item counter=off
2060    Force a 'cut-down' L2TPv3 with no counter as in
2061draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00
2062@item pincounter=on
2063    Work around broken counter handling in peer. This may also help on
2064networks which have packet reorder.
2065@item offset=@var{offset}
2066    Add an extra offset between header and data
2067
2068For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan
2069on the remote Linux host 1.2.3.4:
2070@example
2071# Setup tunnel on linux host using raw ip as encapsulation
2072# on 1.2.3.4
2073ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \
2074    encap udp udp_sport 16384 udp_dport 16384
2075ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \
2076    0xFFFFFFFF peer_session_id 0xFFFFFFFF
2077ifconfig vmtunnel0 mtu 1500
2078ifconfig vmtunnel0 up
2079brctl addif br-lan vmtunnel0
2080
2081
2082# on 4.3.2.1
2083# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter
2084
2085qemu-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
2086
2087
2088@end example
2089
2090@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2091@itemx -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2092Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
2093listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
2094and MODE @var{octalmode} to change default ownership and permissions for
2095communication port. This option is only available if QEMU has been compiled
2096with vde support enabled.
2097
2098Example:
2099@example
2100# launch vde switch
2101vde_switch -F -sock /tmp/myswitch
2102# launch QEMU instance
2103qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch
2104@end example
2105
2106@item -netdev hubport,id=@var{id},hubid=@var{hubid}
2107
2108Create a hub port on QEMU "vlan" @var{hubid}.
2109
2110The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single
2111netdev.  @code{-net} and @code{-device} with parameter @option{vlan} create the
2112required hub automatically.
2113
2114@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n]
2115
2116Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should
2117be a unix domain socket backed one. The vhost-user uses a specifically defined
2118protocol to pass vhost ioctl replacement messages to an application on the other
2119end of the socket. On non-MSIX guests, the feature can be forced with
2120@var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to
2121be created for multiqueue vhost-user.
2122
2123Example:
2124@example
2125qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \
2126     -numa node,memdev=mem \
2127     -chardev socket,path=/path/to/socket \
2128     -netdev type=vhost-user,id=net0,chardev=chr0 \
2129     -device virtio-net-pci,netdev=net0
2130@end example
2131
2132@item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
2133Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
2134At most @var{len} bytes (64k by default) per packet are stored. The file format is
2135libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
2136Note: For devices created with '-netdev', use '-object filter-dump,...' instead.
2137
2138@item -net none
2139Indicate that no network devices should be configured. It is used to
2140override the default configuration (@option{-net nic -net user}) which
2141is activated if no @option{-net} options are provided.
2142ETEXI
2143
2144STEXI
2145@end table
2146ETEXI
2147DEFHEADING()
2148
2149DEFHEADING(Character device options)
2150STEXI
2151
2152The general form of a character device option is:
2153@table @option
2154ETEXI
2155
2156DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
2157    "-chardev help\n"
2158    "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2159    "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
2160    "         [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n"
2161    "         [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n"
2162    "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n"
2163    "         [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n"
2164    "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
2165    "         [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
2166    "         [,logfile=PATH][,logappend=on|off]\n"
2167    "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2168    "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
2169    "         [,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2170    "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n"
2171    "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2172    "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2173#ifdef _WIN32
2174    "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2175    "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2176#else
2177    "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2178    "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n"
2179#endif
2180#ifdef CONFIG_BRLAPI
2181    "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2182#endif
2183#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
2184        || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
2185    "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2186    "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2187#endif
2188#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
2189    "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2190    "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n"
2191#endif
2192#if defined(CONFIG_SPICE)
2193    "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2194    "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n"
2195#endif
2196    , QEMU_ARCH_ALL
2197)
2198
2199STEXI
2200@item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
2201@findex -chardev
2202Backend is one of:
2203@option{null},
2204@option{socket},
2205@option{udp},
2206@option{msmouse},
2207@option{vc},
2208@option{ringbuf},
2209@option{file},
2210@option{pipe},
2211@option{console},
2212@option{serial},
2213@option{pty},
2214@option{stdio},
2215@option{braille},
2216@option{tty},
2217@option{parallel},
2218@option{parport},
2219@option{spicevmc}.
2220@option{spiceport}.
2221The specific backend will determine the applicable options.
2222
2223Use "-chardev help" to print all available chardev backend types.
2224
2225All devices must have an id, which can be any string up to 127 characters long.
2226It is used to uniquely identify this device in other command line directives.
2227
2228A character device may be used in multiplexing mode by multiple front-ends.
2229Specify @option{mux=on} to enable this mode.
2230A multiplexer is a "1:N" device, and here the "1" end is your specified chardev
2231backend, and the "N" end is the various parts of QEMU that can talk to a chardev.
2232If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will
2233create a multiplexer with your specified ID, and you can then configure multiple
2234front ends to use that chardev ID for their input/output. Up to four different
2235front ends can be connected to a single multiplexed chardev. (Without
2236multiplexing enabled, a chardev can only be used by a single front end.)
2237For instance you could use this to allow a single stdio chardev to be used by
2238two serial ports and the QEMU monitor:
2239
2240@example
2241-chardev stdio,mux=on,id=char0 \
2242-mon chardev=char0,mode=readline \
2243-serial chardev:char0 \
2244-serial chardev:char0
2245@end example
2246
2247You can have more than one multiplexer in a system configuration; for instance
2248you could have a TCP port multiplexed between UART 0 and UART 1, and stdio
2249multiplexed between the QEMU monitor and a parallel port:
2250
2251@example
2252-chardev stdio,mux=on,id=char0 \
2253-mon chardev=char0,mode=readline \
2254-parallel chardev:char0 \
2255-chardev tcp,...,mux=on,id=char1 \
2256-serial chardev:char1 \
2257-serial chardev:char1
2258@end example
2259
2260When you're using a multiplexed character device, some escape sequences are
2261interpreted in the input. @xref{mux_keys, Keys in the character backend
2262multiplexer}.
2263
2264Note that some other command line options may implicitly create multiplexed
2265character backends; for instance @option{-serial mon:stdio} creates a
2266multiplexed stdio backend connected to the serial port and the QEMU monitor,
2267and @option{-nographic} also multiplexes the console and the monitor to
2268stdio.
2269
2270There is currently no support for multiplexing in the other direction
2271(where a single QEMU front end takes input and output from multiple chardevs).
2272
2273Every backend supports the @option{logfile} option, which supplies the path
2274to a file to record all data transmitted via the backend. The @option{logappend}
2275option controls whether the log file will be truncated or appended to when
2276opened.
2277
2278Further options to each backend are described below.
2279
2280@item -chardev null ,id=@var{id}
2281A void device. This device will not emit any data, and will drop any data it
2282receives. The null backend does not take any options.
2283
2284@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}] [,tls-creds=@var{id}]
2285
2286Create a two-way stream socket, which can be either a TCP or a unix socket. A
2287unix socket will be created if @option{path} is specified. Behaviour is
2288undefined if TCP options are specified for a unix socket.
2289
2290@option{server} specifies that the socket shall be a listening socket.
2291
2292@option{nowait} specifies that QEMU should not block waiting for a client to
2293connect to a listening socket.
2294
2295@option{telnet} specifies that traffic on the socket should interpret telnet
2296escape sequences.
2297
2298@option{reconnect} sets the timeout for reconnecting on non-server sockets when
2299the remote end goes away.  qemu will delay this many seconds and then attempt
2300to reconnect.  Zero disables reconnecting, and is the default.
2301
2302@option{tls-creds} requests enablement of the TLS protocol for encryption,
2303and specifies the id of the TLS credentials to use for the handshake. The
2304credentials must be previously created with the @option{-object tls-creds}
2305argument.
2306
2307TCP and unix socket options are given below:
2308
2309@table @option
2310
2311@item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
2312
2313@option{host} for a listening socket specifies the local address to be bound.
2314For a connecting socket species the remote host to connect to. @option{host} is
2315optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
2316
2317@option{port} for a listening socket specifies the local port to be bound. For a
2318connecting socket specifies the port on the remote host to connect to.
2319@option{port} can be given as either a port number or a service name.
2320@option{port} is required.
2321
2322@option{to} is only relevant to listening sockets. If it is specified, and
2323@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
2324to and including @option{to} until it succeeds. @option{to} must be specified
2325as a port number.
2326
2327@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2328If neither is specified the socket may use either protocol.
2329
2330@option{nodelay} disables the Nagle algorithm.
2331
2332@item unix options: path=@var{path}
2333
2334@option{path} specifies the local path of the unix socket. @option{path} is
2335required.
2336
2337@end table
2338
2339@item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
2340
2341Sends all traffic from the guest to a remote host over UDP.
2342
2343@option{host} specifies the remote host to connect to. If not specified it
2344defaults to @code{localhost}.
2345
2346@option{port} specifies the port on the remote host to connect to. @option{port}
2347is required.
2348
2349@option{localaddr} specifies the local address to bind to. If not specified it
2350defaults to @code{0.0.0.0}.
2351
2352@option{localport} specifies the local port to bind to. If not specified any
2353available local port will be used.
2354
2355@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2356If neither is specified the device may use either protocol.
2357
2358@item -chardev msmouse ,id=@var{id}
2359
2360Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
2361take any options.
2362
2363@item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
2364
2365Connect to a QEMU text console. @option{vc} may optionally be given a specific
2366size.
2367
2368@option{width} and @option{height} specify the width and height respectively of
2369the console, in pixels.
2370
2371@option{cols} and @option{rows} specify that the console be sized to fit a text
2372console with the given dimensions.
2373
2374@item -chardev ringbuf ,id=@var{id} [,size=@var{size}]
2375
2376Create a ring buffer with fixed size @option{size}.
2377@var{size} must be a power of two and defaults to @code{64K}.
2378
2379@item -chardev file ,id=@var{id} ,path=@var{path}
2380
2381Log all traffic received from the guest to a file.
2382
2383@option{path} specifies the path of the file to be opened. This file will be
2384created if it does not already exist, and overwritten if it does. @option{path}
2385is required.
2386
2387@item -chardev pipe ,id=@var{id} ,path=@var{path}
2388
2389Create a two-way connection to the guest. The behaviour differs slightly between
2390Windows hosts and other hosts:
2391
2392On Windows, a single duplex pipe will be created at
2393@file{\\.pipe\@option{path}}.
2394
2395On other hosts, 2 pipes will be created called @file{@option{path}.in} and
2396@file{@option{path}.out}. Data written to @file{@option{path}.in} will be
2397received by the guest. Data written by the guest can be read from
2398@file{@option{path}.out}. QEMU will not create these fifos, and requires them to
2399be present.
2400
2401@option{path} forms part of the pipe path as described above. @option{path} is
2402required.
2403
2404@item -chardev console ,id=@var{id}
2405
2406Send traffic from the guest to QEMU's standard output. @option{console} does not
2407take any options.
2408
2409@option{console} is only available on Windows hosts.
2410
2411@item -chardev serial ,id=@var{id} ,path=@option{path}
2412
2413Send traffic from the guest to a serial device on the host.
2414
2415On Unix hosts serial will actually accept any tty device,
2416not only serial lines.
2417
2418@option{path} specifies the name of the serial device to open.
2419
2420@item -chardev pty ,id=@var{id}
2421
2422Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2423not take any options.
2424
2425@option{pty} is not available on Windows hosts.
2426
2427@item -chardev stdio ,id=@var{id} [,signal=on|off]
2428Connect to standard input and standard output of the QEMU process.
2429
2430@option{signal} controls if signals are enabled on the terminal, that includes
2431exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2432default, use @option{signal=off} to disable it.
2433
2434@option{stdio} is not available on Windows hosts.
2435
2436@item -chardev braille ,id=@var{id}
2437
2438Connect to a local BrlAPI server. @option{braille} does not take any options.
2439
2440@item -chardev tty ,id=@var{id} ,path=@var{path}
2441
2442@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2443DragonFlyBSD hosts.  It is an alias for @option{serial}.
2444
2445@option{path} specifies the path to the tty. @option{path} is required.
2446
2447@item -chardev parallel ,id=@var{id} ,path=@var{path}
2448@itemx -chardev parport ,id=@var{id} ,path=@var{path}
2449
2450@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2451
2452Connect to a local parallel port.
2453
2454@option{path} specifies the path to the parallel port device. @option{path} is
2455required.
2456
2457@item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2458
2459@option{spicevmc} is only available when spice support is built in.
2460
2461@option{debug} debug level for spicevmc
2462
2463@option{name} name of spice channel to connect to
2464
2465Connect to a spice virtual machine channel, such as vdiport.
2466
2467@item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2468
2469@option{spiceport} is only available when spice support is built in.
2470
2471@option{debug} debug level for spicevmc
2472
2473@option{name} name of spice port to connect to
2474
2475Connect to a spice port, allowing a Spice client to handle the traffic
2476identified by a name (preferably a fqdn).
2477ETEXI
2478
2479STEXI
2480@end table
2481ETEXI
2482DEFHEADING()
2483
2484DEFHEADING(Device URL Syntax)
2485STEXI
2486
2487In addition to using normal file images for the emulated storage devices,
2488QEMU can also use networked resources such as iSCSI devices. These are
2489specified using a special URL syntax.
2490
2491@table @option
2492@item iSCSI
2493iSCSI support allows QEMU to access iSCSI resources directly and use as
2494images for the guest storage. Both disk and cdrom images are supported.
2495
2496Syntax for specifying iSCSI LUNs is
2497``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
2498
2499By default qemu will use the iSCSI initiator-name
2500'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command
2501line or a configuration file.
2502
2503Since version Qemu 2.4 it is possible to specify a iSCSI request timeout to detect
2504stalled requests and force a reestablishment of the session. The timeout
2505is specified in seconds. The default is 0 which means no timeout. Libiscsi
25061.15.0 or greater is required for this feature.
2507
2508Example (without authentication):
2509@example
2510qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
2511                 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
2512                 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2513@end example
2514
2515Example (CHAP username/password via URL):
2516@example
2517qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
2518@end example
2519
2520Example (CHAP username/password via environment variables):
2521@example
2522LIBISCSI_CHAP_USERNAME="user" \
2523LIBISCSI_CHAP_PASSWORD="password" \
2524qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2525@end example
2526
2527iSCSI support is an optional feature of QEMU and only available when
2528compiled and linked against libiscsi.
2529ETEXI
2530DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
2531    "-iscsi [user=user][,password=password]\n"
2532    "       [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
2533    "       [,initiator-name=initiator-iqn][,id=target-iqn]\n"
2534    "       [,timeout=timeout]\n"
2535    "                iSCSI session parameters\n", QEMU_ARCH_ALL)
2536STEXI
2537
2538iSCSI parameters such as username and password can also be specified via
2539a configuration file. See qemu-doc for more information and examples.
2540
2541@item NBD
2542QEMU supports NBD (Network Block Devices) both using TCP protocol as well
2543as Unix Domain Sockets.
2544
2545Syntax for specifying a NBD device using TCP
2546``nbd:<server-ip>:<port>[:exportname=<export>]''
2547
2548Syntax for specifying a NBD device using Unix Domain Sockets
2549``nbd:unix:<domain-socket>[:exportname=<export>]''
2550
2551
2552Example for TCP
2553@example
2554qemu-system-i386 --drive file=nbd:192.0.2.1:30000
2555@end example
2556
2557Example for Unix Domain Sockets
2558@example
2559qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket
2560@end example
2561
2562@item SSH
2563QEMU supports SSH (Secure Shell) access to remote disks.
2564
2565Examples:
2566@example
2567qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img
2568qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img
2569@end example
2570
2571Currently authentication must be done using ssh-agent.  Other
2572authentication methods may be supported in future.
2573
2574@item Sheepdog
2575Sheepdog is a distributed storage system for QEMU.
2576QEMU supports using either local sheepdog devices or remote networked
2577devices.
2578
2579Syntax for specifying a sheepdog device
2580@example
2581sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag]
2582@end example
2583
2584Example
2585@example
2586qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine
2587@end example
2588
2589See also @url{http://http://www.osrg.net/sheepdog/}.
2590
2591@item GlusterFS
2592GlusterFS is an user space distributed file system.
2593QEMU supports the use of GlusterFS volumes for hosting VM disk images using
2594TCP, Unix Domain Sockets and RDMA transport protocols.
2595
2596Syntax for specifying a VM disk image on GlusterFS volume is
2597@example
2598
2599URI:
2600gluster[+type]://[host[:port]]/volume/path[?socket=...][,debug=N][,logfile=...]
2601
2602JSON:
2603'json:@{"driver":"qcow2","file":@{"driver":"gluster","volume":"testvol","path":"a.img","debug":N,"logfile":"...",
2604@                                 "server":[@{"type":"tcp","host":"...","port":"..."@},
2605@                                           @{"type":"unix","socket":"..."@}]@}@}'
2606@end example
2607
2608
2609Example
2610@example
2611URI:
2612qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img,
2613@                               file.debug=9,file.logfile=/var/log/qemu-gluster.log
2614
2615JSON:
2616qemu-system-x86_64 'json:@{"driver":"qcow2",
2617@                          "file":@{"driver":"gluster",
2618@                                   "volume":"testvol","path":"a.img",
2619@                                   "debug":9,"logfile":"/var/log/qemu-gluster.log",
2620@                                   "server":[@{"type":"tcp","host":"1.2.3.4","port":24007@},
2621@                                             @{"type":"unix","socket":"/var/run/glusterd.socket"@}]@}@}'
2622qemu-system-x86_64 -drive driver=qcow2,file.driver=gluster,file.volume=testvol,file.path=/path/a.img,
2623@                                      file.debug=9,file.logfile=/var/log/qemu-gluster.log,
2624@                                      file.server.0.type=tcp,file.server.0.host=1.2.3.4,file.server.0.port=24007,
2625@                                      file.server.1.type=unix,file.server.1.socket=/var/run/glusterd.socket
2626@end example
2627
2628See also @url{http://www.gluster.org}.
2629
2630@item HTTP/HTTPS/FTP/FTPS
2631QEMU supports read-only access to files accessed over http(s) and ftp(s).
2632
2633Syntax using a single filename:
2634@example
2635<protocol>://[<username>[:<password>]@@]<host>/<path>
2636@end example
2637
2638where:
2639@table @option
2640@item protocol
2641'http', 'https', 'ftp', or 'ftps'.
2642
2643@item username
2644Optional username for authentication to the remote server.
2645
2646@item password
2647Optional password for authentication to the remote server.
2648
2649@item host
2650Address of the remote server.
2651
2652@item path
2653Path on the remote server, including any query string.
2654@end table
2655
2656The following options are also supported:
2657@table @option
2658@item url
2659The full URL when passing options to the driver explicitly.
2660
2661@item readahead
2662The amount of data to read ahead with each range request to the remote server.
2663This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it
2664does not have a suffix, it will be assumed to be in bytes. The value must be a
2665multiple of 512 bytes. It defaults to 256k.
2666
2667@item sslverify
2668Whether to verify the remote server's certificate when connecting over SSL. It
2669can have the value 'on' or 'off'. It defaults to 'on'.
2670
2671@item cookie
2672Send this cookie (it can also be a list of cookies separated by ';') with
2673each outgoing request.  Only supported when using protocols such as HTTP
2674which support cookies, otherwise ignored.
2675
2676@item timeout
2677Set the timeout in seconds of the CURL connection. This timeout is the time
2678that CURL waits for a response from the remote server to get the size of the
2679image to be downloaded. If not set, the default timeout of 5 seconds is used.
2680@end table
2681
2682Note that when passing options to qemu explicitly, @option{driver} is the value
2683of <protocol>.
2684
2685Example: boot from a remote Fedora 20 live ISO image
2686@example
2687qemu-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
2688
2689qemu-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
2690@end example
2691
2692Example: boot from a remote Fedora 20 cloud image using a local overlay for
2693writes, copy-on-read, and a readahead of 64k
2694@example
2695qemu-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
2696
2697qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on
2698@end example
2699
2700Example: boot from an image stored on a VMware vSphere server with a self-signed
2701certificate using a local overlay for writes, a readahead of 64k and a timeout
2702of 10 seconds.
2703@example
2704qemu-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
2705
2706qemu-system-x86_64 -drive file=/tmp/test.qcow2
2707@end example
2708ETEXI
2709
2710STEXI
2711@end table
2712ETEXI
2713
2714DEFHEADING(Bluetooth(R) options)
2715STEXI
2716@table @option
2717ETEXI
2718
2719DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
2720    "-bt hci,null    dumb bluetooth HCI - doesn't respond to commands\n" \
2721    "-bt hci,host[:id]\n" \
2722    "                use host's HCI with the given name\n" \
2723    "-bt hci[,vlan=n]\n" \
2724    "                emulate a standard HCI in virtual scatternet 'n'\n" \
2725    "-bt vhci[,vlan=n]\n" \
2726    "                add host computer to virtual scatternet 'n' using VHCI\n" \
2727    "-bt device:dev[,vlan=n]\n" \
2728    "                emulate a bluetooth device 'dev' in scatternet 'n'\n",
2729    QEMU_ARCH_ALL)
2730STEXI
2731@item -bt hci[...]
2732@findex -bt
2733Defines the function of the corresponding Bluetooth HCI.  -bt options
2734are matched with the HCIs present in the chosen machine type.  For
2735example when emulating a machine with only one HCI built into it, only
2736the first @code{-bt hci[...]} option is valid and defines the HCI's
2737logic.  The Transport Layer is decided by the machine type.  Currently
2738the machines @code{n800} and @code{n810} have one HCI and all other
2739machines have none.
2740
2741@anchor{bt-hcis}
2742The following three types are recognized:
2743
2744@table @option
2745@item -bt hci,null
2746(default) The corresponding Bluetooth HCI assumes no internal logic
2747and will not respond to any HCI commands or emit events.
2748
2749@item -bt hci,host[:@var{id}]
2750(@code{bluez} only) The corresponding HCI passes commands / events
2751to / from the physical HCI identified by the name @var{id} (default:
2752@code{hci0}) on the computer running QEMU.  Only available on @code{bluez}
2753capable systems like Linux.
2754
2755@item -bt hci[,vlan=@var{n}]
2756Add a virtual, standard HCI that will participate in the Bluetooth
2757scatternet @var{n} (default @code{0}).  Similarly to @option{-net}
2758VLANs, devices inside a bluetooth network @var{n} can only communicate
2759with other devices in the same network (scatternet).
2760@end table
2761
2762@item -bt vhci[,vlan=@var{n}]
2763(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2764to the host bluetooth stack instead of to the emulated target.  This
2765allows the host and target machines to participate in a common scatternet
2766and communicate.  Requires the Linux @code{vhci} driver installed.  Can
2767be used as following:
2768
2769@example
2770qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2771@end example
2772
2773@item -bt device:@var{dev}[,vlan=@var{n}]
2774Emulate a bluetooth device @var{dev} and place it in network @var{n}
2775(default @code{0}).  QEMU can only emulate one type of bluetooth devices
2776currently:
2777
2778@table @option
2779@item keyboard
2780Virtual wireless keyboard implementing the HIDP bluetooth profile.
2781@end table
2782ETEXI
2783
2784STEXI
2785@end table
2786ETEXI
2787DEFHEADING()
2788
2789#ifdef CONFIG_TPM
2790DEFHEADING(TPM device options)
2791
2792DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
2793    "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n"
2794    "                use path to provide path to a character device; default is /dev/tpm0\n"
2795    "                use cancel-path to provide path to TPM's cancel sysfs entry; if\n"
2796    "                not provided it will be searched for in /sys/class/misc/tpm?/device\n",
2797    QEMU_ARCH_ALL)
2798STEXI
2799
2800The general form of a TPM device option is:
2801@table @option
2802
2803@item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
2804@findex -tpmdev
2805Backend type must be:
2806@option{passthrough}.
2807
2808The specific backend type will determine the applicable options.
2809The @code{-tpmdev} option creates the TPM backend and requires a
2810@code{-device} option that specifies the TPM frontend interface model.
2811
2812Options to each backend are described below.
2813
2814Use 'help' to print all available TPM backend types.
2815@example
2816qemu -tpmdev help
2817@end example
2818
2819@item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path}
2820
2821(Linux-host only) Enable access to the host's TPM using the passthrough
2822driver.
2823
2824@option{path} specifies the path to the host's TPM device, i.e., on
2825a Linux host this would be @code{/dev/tpm0}.
2826@option{path} is optional and by default @code{/dev/tpm0} is used.
2827
2828@option{cancel-path} specifies the path to the host TPM device's sysfs
2829entry allowing for cancellation of an ongoing TPM command.
2830@option{cancel-path} is optional and by default QEMU will search for the
2831sysfs entry to use.
2832
2833Some notes about using the host's TPM with the passthrough driver:
2834
2835The TPM device accessed by the passthrough driver must not be
2836used by any other application on the host.
2837
2838Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
2839the VM's firmware (BIOS/UEFI) will not be able to initialize the
2840TPM again and may therefore not show a TPM-specific menu that would
2841otherwise allow the user to configure the TPM, e.g., allow the user to
2842enable/disable or activate/deactivate the TPM.
2843Further, if TPM ownership is released from within a VM then the host's TPM
2844will get disabled and deactivated. To enable and activate the
2845TPM again afterwards, the host has to be rebooted and the user is
2846required to enter the firmware's menu to enable and activate the TPM.
2847If the TPM is left disabled and/or deactivated most TPM commands will fail.
2848
2849To create a passthrough TPM use the following two options:
2850@example
2851-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
2852@end example
2853Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
2854@code{tpmdev=tpm0} in the device option.
2855
2856@end table
2857
2858ETEXI
2859
2860DEFHEADING()
2861
2862#endif
2863
2864DEFHEADING(Linux/Multiboot boot specific)
2865STEXI
2866
2867When using these options, you can use a given Linux or Multiboot
2868kernel without installing it in the disk image. It can be useful
2869for easier testing of various kernels.
2870
2871@table @option
2872ETEXI
2873
2874DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
2875    "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL)
2876STEXI
2877@item -kernel @var{bzImage}
2878@findex -kernel
2879Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2880or in multiboot format.
2881ETEXI
2882
2883DEF("append", HAS_ARG, QEMU_OPTION_append, \
2884    "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL)
2885STEXI
2886@item -append @var{cmdline}
2887@findex -append
2888Use @var{cmdline} as kernel command line
2889ETEXI
2890
2891DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
2892           "-initrd file    use 'file' as initial ram disk\n", QEMU_ARCH_ALL)
2893STEXI
2894@item -initrd @var{file}
2895@findex -initrd
2896Use @var{file} as initial ram disk.
2897
2898@item -initrd "@var{file1} arg=foo,@var{file2}"
2899
2900This syntax is only available with multiboot.
2901
2902Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
2903first module.
2904ETEXI
2905
2906DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
2907    "-dtb    file    use 'file' as device tree image\n", QEMU_ARCH_ALL)
2908STEXI
2909@item -dtb @var{file}
2910@findex -dtb
2911Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
2912on boot.
2913ETEXI
2914
2915STEXI
2916@end table
2917ETEXI
2918DEFHEADING()
2919
2920DEFHEADING(Debug/Expert options)
2921STEXI
2922@table @option
2923ETEXI
2924
2925DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg,
2926    "-fw_cfg [name=]<name>,file=<file>\n"
2927    "                add named fw_cfg entry with contents from file\n"
2928    "-fw_cfg [name=]<name>,string=<str>\n"
2929    "                add named fw_cfg entry with contents from string\n",
2930    QEMU_ARCH_ALL)
2931STEXI
2932
2933@item -fw_cfg [name=]@var{name},file=@var{file}
2934@findex -fw_cfg
2935Add named fw_cfg entry with contents from file @var{file}.
2936
2937@item -fw_cfg [name=]@var{name},string=@var{str}
2938Add named fw_cfg entry with contents from string @var{str}.
2939
2940The terminating NUL character of the contents of @var{str} will not be
2941included as part of the fw_cfg item data. To insert contents with
2942embedded NUL characters, you have to use the @var{file} parameter.
2943
2944The fw_cfg entries are passed by QEMU through to the guest.
2945
2946Example:
2947@example
2948    -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin
2949@end example
2950creates an fw_cfg entry named opt/com.mycompany/blob with contents
2951from ./my_blob.bin.
2952
2953ETEXI
2954
2955DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
2956    "-serial dev     redirect the serial port to char device 'dev'\n",
2957    QEMU_ARCH_ALL)
2958STEXI
2959@item -serial @var{dev}
2960@findex -serial
2961Redirect the virtual serial port to host character device
2962@var{dev}. The default device is @code{vc} in graphical mode and
2963@code{stdio} in non graphical mode.
2964
2965This option can be used several times to simulate up to 4 serial
2966ports.
2967
2968Use @code{-serial none} to disable all serial ports.
2969
2970Available character devices are:
2971@table @option
2972@item vc[:@var{W}x@var{H}]
2973Virtual console. Optionally, a width and height can be given in pixel with
2974@example
2975vc:800x600
2976@end example
2977It is also possible to specify width or height in characters:
2978@example
2979vc:80Cx24C
2980@end example
2981@item pty
2982[Linux only] Pseudo TTY (a new PTY is automatically allocated)
2983@item none
2984No device is allocated.
2985@item null
2986void device
2987@item chardev:@var{id}
2988Use a named character device defined with the @code{-chardev} option.
2989@item /dev/XXX
2990[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
2991parameters are set according to the emulated ones.
2992@item /dev/parport@var{N}
2993[Linux only, parallel port only] Use host parallel port
2994@var{N}. Currently SPP and EPP parallel port features can be used.
2995@item file:@var{filename}
2996Write output to @var{filename}. No character can be read.
2997@item stdio
2998[Unix only] standard input/output
2999@item pipe:@var{filename}
3000name pipe @var{filename}
3001@item COM@var{n}
3002[Windows only] Use host serial port @var{n}
3003@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
3004This implements UDP Net Console.
3005When @var{remote_host} or @var{src_ip} are not specified
3006they default to @code{0.0.0.0}.
3007When not using a specified @var{src_port} a random port is automatically chosen.
3008
3009If you just want a simple readonly console you can use @code{netcat} or
3010@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
3011@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
3012will appear in the netconsole session.
3013
3014If you plan to send characters back via netconsole or you want to stop
3015and start QEMU a lot of times, you should have QEMU use the same
3016source port each time by using something like @code{-serial
3017udp::4555@@:4556} to QEMU. Another approach is to use a patched
3018version of netcat which can listen to a TCP port and send and receive
3019characters via udp.  If you have a patched version of netcat which
3020activates telnet remote echo and single char transfer, then you can
3021use the following options to step up a netcat redirector to allow
3022telnet on port 5555 to access the QEMU port.
3023@table @code
3024@item QEMU Options:
3025-serial udp::4555@@:4556
3026@item netcat options:
3027-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
3028@item telnet options:
3029localhost 5555
3030@end table
3031
3032@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}]
3033The TCP Net Console has two modes of operation.  It can send the serial
3034I/O to a location or wait for a connection from a location.  By default
3035the TCP Net Console is sent to @var{host} at the @var{port}.  If you use
3036the @var{server} option QEMU will wait for a client socket application
3037to connect to the port before continuing, unless the @code{nowait}
3038option was specified.  The @code{nodelay} option disables the Nagle buffering
3039algorithm.  The @code{reconnect} option only applies if @var{noserver} is
3040set, if the connection goes down it will attempt to reconnect at the
3041given interval.  If @var{host} is omitted, 0.0.0.0 is assumed. Only
3042one TCP connection at a time is accepted. You can use @code{telnet} to
3043connect to the corresponding character device.
3044@table @code
3045@item Example to send tcp console to 192.168.0.2 port 4444
3046-serial tcp:192.168.0.2:4444
3047@item Example to listen and wait on port 4444 for connection
3048-serial tcp::4444,server
3049@item Example to not wait and listen on ip 192.168.0.100 port 4444
3050-serial tcp:192.168.0.100:4444,server,nowait
3051@end table
3052
3053@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
3054The telnet protocol is used instead of raw tcp sockets.  The options
3055work the same as if you had specified @code{-serial tcp}.  The
3056difference is that the port acts like a telnet server or client using
3057telnet option negotiation.  This will also allow you to send the
3058MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
3059sequence.  Typically in unix telnet you do it with Control-] and then
3060type "send break" followed by pressing the enter key.
3061
3062@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}]
3063A unix domain socket is used instead of a tcp socket.  The option works the
3064same as if you had specified @code{-serial tcp} except the unix domain socket
3065@var{path} is used for connections.
3066
3067@item mon:@var{dev_string}
3068This is a special option to allow the monitor to be multiplexed onto
3069another serial port.  The monitor is accessed with key sequence of
3070@key{Control-a} and then pressing @key{c}.
3071@var{dev_string} should be any one of the serial devices specified
3072above.  An example to multiplex the monitor onto a telnet server
3073listening on port 4444 would be:
3074@table @code
3075@item -serial mon:telnet::4444,server,nowait
3076@end table
3077When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
3078QEMU any more but will be passed to the guest instead.
3079
3080@item braille
3081Braille device.  This will use BrlAPI to display the braille output on a real
3082or fake device.
3083
3084@item msmouse
3085Three button serial mouse. Configure the guest to use Microsoft protocol.
3086@end table
3087ETEXI
3088
3089DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
3090    "-parallel dev   redirect the parallel port to char device 'dev'\n",
3091    QEMU_ARCH_ALL)
3092STEXI
3093@item -parallel @var{dev}
3094@findex -parallel
3095Redirect the virtual parallel port to host device @var{dev} (same
3096devices as the serial port). On Linux hosts, @file{/dev/parportN} can
3097be used to use hardware devices connected on the corresponding host
3098parallel port.
3099
3100This option can be used several times to simulate up to 3 parallel
3101ports.
3102
3103Use @code{-parallel none} to disable all parallel ports.
3104ETEXI
3105
3106DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
3107    "-monitor dev    redirect the monitor to char device 'dev'\n",
3108    QEMU_ARCH_ALL)
3109STEXI
3110@item -monitor @var{dev}
3111@findex -monitor
3112Redirect the monitor to host device @var{dev} (same devices as the
3113serial port).
3114The default device is @code{vc} in graphical mode and @code{stdio} in
3115non graphical mode.
3116Use @code{-monitor none} to disable the default monitor.
3117ETEXI
3118DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
3119    "-qmp dev        like -monitor but opens in 'control' mode\n",
3120    QEMU_ARCH_ALL)
3121STEXI
3122@item -qmp @var{dev}
3123@findex -qmp
3124Like -monitor but opens in 'control' mode.
3125ETEXI
3126DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \
3127    "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n",
3128    QEMU_ARCH_ALL)
3129STEXI
3130@item -qmp-pretty @var{dev}
3131@findex -qmp-pretty
3132Like -qmp but uses pretty JSON formatting.
3133ETEXI
3134
3135DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
3136    "-mon [chardev=]name[,mode=readline|control]\n", QEMU_ARCH_ALL)
3137STEXI
3138@item -mon [chardev=]name[,mode=readline|control]
3139@findex -mon
3140Setup monitor on chardev @var{name}.
3141ETEXI
3142
3143DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
3144    "-debugcon dev   redirect the debug console to char device 'dev'\n",
3145    QEMU_ARCH_ALL)
3146STEXI
3147@item -debugcon @var{dev}
3148@findex -debugcon
3149Redirect the debug console to host device @var{dev} (same devices as the
3150serial port).  The debug console is an I/O port which is typically port
31510xe9; writing to that I/O port sends output to this device.
3152The default device is @code{vc} in graphical mode and @code{stdio} in
3153non graphical mode.
3154ETEXI
3155
3156DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
3157    "-pidfile file   write PID to 'file'\n", QEMU_ARCH_ALL)
3158STEXI
3159@item -pidfile @var{file}
3160@findex -pidfile
3161Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
3162from a script.
3163ETEXI
3164
3165DEF("singlestep", 0, QEMU_OPTION_singlestep, \
3166    "-singlestep     always run in singlestep mode\n", QEMU_ARCH_ALL)
3167STEXI
3168@item -singlestep
3169@findex -singlestep
3170Run the emulation in single step mode.
3171ETEXI
3172
3173DEF("S", 0, QEMU_OPTION_S, \
3174    "-S              freeze CPU at startup (use 'c' to start execution)\n",
3175    QEMU_ARCH_ALL)
3176STEXI
3177@item -S
3178@findex -S
3179Do not start CPU at startup (you must type 'c' in the monitor).
3180ETEXI
3181
3182DEF("realtime", HAS_ARG, QEMU_OPTION_realtime,
3183    "-realtime [mlock=on|off]\n"
3184    "                run qemu with realtime features\n"
3185    "                mlock=on|off controls mlock support (default: on)\n",
3186    QEMU_ARCH_ALL)
3187STEXI
3188@item -realtime mlock=on|off
3189@findex -realtime
3190Run qemu with realtime features.
3191mlocking qemu and guest memory can be enabled via @option{mlock=on}
3192(enabled by default).
3193ETEXI
3194
3195DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
3196    "-gdb dev        wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL)
3197STEXI
3198@item -gdb @var{dev}
3199@findex -gdb
3200Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
3201connections will likely be TCP-based, but also UDP, pseudo TTY, or even
3202stdio are reasonable use case. The latter is allowing to start QEMU from
3203within gdb and establish the connection via a pipe:
3204@example
3205(gdb) target remote | exec qemu-system-i386 -gdb stdio ...
3206@end example
3207ETEXI
3208
3209DEF("s", 0, QEMU_OPTION_s, \
3210    "-s              shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
3211    QEMU_ARCH_ALL)
3212STEXI
3213@item -s
3214@findex -s
3215Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
3216(@pxref{gdb_usage}).
3217ETEXI
3218
3219DEF("d", HAS_ARG, QEMU_OPTION_d, \
3220    "-d item1,...    enable logging of specified items (use '-d help' for a list of log items)\n",
3221    QEMU_ARCH_ALL)
3222STEXI
3223@item -d @var{item1}[,...]
3224@findex -d
3225Enable logging of specified items. Use '-d help' for a list of log items.
3226ETEXI
3227
3228DEF("D", HAS_ARG, QEMU_OPTION_D, \
3229    "-D logfile      output log to logfile (default stderr)\n",
3230    QEMU_ARCH_ALL)
3231STEXI
3232@item -D @var{logfile}
3233@findex -D
3234Output log in @var{logfile} instead of to stderr
3235ETEXI
3236
3237DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \
3238    "-dfilter range,..  filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n",
3239    QEMU_ARCH_ALL)
3240STEXI
3241@item -dfilter @var{range1}[,...]
3242@findex -dfilter
3243Filter debug output to that relevant to a range of target addresses. The filter
3244spec can be either @var{start}+@var{size}, @var{start}-@var{size} or
3245@var{start}..@var{end} where @var{start} @var{end} and @var{size} are the
3246addresses and sizes required. For example:
3247@example
3248    -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000
3249@end example
3250Will dump output for any code in the 0x1000 sized block starting at 0x8000 and
3251the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized
3252block starting at 0xffffffc00005f000.
3253ETEXI
3254
3255DEF("L", HAS_ARG, QEMU_OPTION_L, \
3256    "-L path         set the directory for the BIOS, VGA BIOS and keymaps\n",
3257    QEMU_ARCH_ALL)
3258STEXI
3259@item -L  @var{path}
3260@findex -L
3261Set the directory for the BIOS, VGA BIOS and keymaps.
3262
3263To list all the data directories, use @code{-L help}.
3264ETEXI
3265
3266DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
3267    "-bios file      set the filename for the BIOS\n", QEMU_ARCH_ALL)
3268STEXI
3269@item -bios @var{file}
3270@findex -bios
3271Set the filename for the BIOS.
3272ETEXI
3273
3274DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
3275    "-enable-kvm     enable KVM full virtualization support\n", QEMU_ARCH_ALL)
3276STEXI
3277@item -enable-kvm
3278@findex -enable-kvm
3279Enable KVM full virtualization support. This option is only available
3280if KVM support is enabled when compiling.
3281ETEXI
3282
3283DEF("enable-hax", 0, QEMU_OPTION_enable_hax, \
3284    "-enable-hax     enable HAX virtualization support\n", QEMU_ARCH_I386)
3285STEXI
3286@item -enable-hax
3287@findex -enable-hax
3288Enable HAX (Hardware-based Acceleration eXecution) support. This option
3289is only available if HAX support is enabled when compiling. HAX is only
3290applicable to MAC and Windows platform, and thus does not conflict with
3291KVM.
3292ETEXI
3293
3294DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
3295    "-xen-domid id   specify xen guest domain id\n", QEMU_ARCH_ALL)
3296DEF("xen-create", 0, QEMU_OPTION_xen_create,
3297    "-xen-create     create domain using xen hypercalls, bypassing xend\n"
3298    "                warning: should not be used when xend is in use\n",
3299    QEMU_ARCH_ALL)
3300DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
3301    "-xen-attach     attach to existing xen domain\n"
3302    "                xend will use this when starting QEMU\n",
3303    QEMU_ARCH_ALL)
3304STEXI
3305@item -xen-domid @var{id}
3306@findex -xen-domid
3307Specify xen guest domain @var{id} (XEN only).
3308@item -xen-create
3309@findex -xen-create
3310Create domain using xen hypercalls, bypassing xend.
3311Warning: should not be used when xend is in use (XEN only).
3312@item -xen-attach
3313@findex -xen-attach
3314Attach to existing xen domain.
3315xend will use this when starting QEMU (XEN only).
3316ETEXI
3317
3318DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
3319    "-no-reboot      exit instead of rebooting\n", QEMU_ARCH_ALL)
3320STEXI
3321@item -no-reboot
3322@findex -no-reboot
3323Exit instead of rebooting.
3324ETEXI
3325
3326DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
3327    "-no-shutdown    stop before shutdown\n", QEMU_ARCH_ALL)
3328STEXI
3329@item -no-shutdown
3330@findex -no-shutdown
3331Don't exit QEMU on guest shutdown, but instead only stop the emulation.
3332This allows for instance switching to monitor to commit changes to the
3333disk image.
3334ETEXI
3335
3336DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
3337    "-loadvm [tag|id]\n" \
3338    "                start right away with a saved state (loadvm in monitor)\n",
3339    QEMU_ARCH_ALL)
3340STEXI
3341@item -loadvm @var{file}
3342@findex -loadvm
3343Start right away with a saved state (@code{loadvm} in monitor)
3344ETEXI
3345
3346#ifndef _WIN32
3347DEF("daemonize", 0, QEMU_OPTION_daemonize, \
3348    "-daemonize      daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
3349#endif
3350STEXI
3351@item -daemonize
3352@findex -daemonize
3353Daemonize the QEMU process after initialization.  QEMU will not detach from
3354standard IO until it is ready to receive connections on any of its devices.
3355This option is a useful way for external programs to launch QEMU without having
3356to cope with initialization race conditions.
3357ETEXI
3358
3359DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
3360    "-option-rom rom load a file, rom, into the option ROM space\n",
3361    QEMU_ARCH_ALL)
3362STEXI
3363@item -option-rom @var{file}
3364@findex -option-rom
3365Load the contents of @var{file} as an option ROM.
3366This option is useful to load things like EtherBoot.
3367ETEXI
3368
3369HXCOMM Silently ignored for compatibility
3370DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL)
3371
3372HXCOMM Options deprecated by -rtc
3373DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
3374DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
3375
3376DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
3377    "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
3378    "                set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
3379    QEMU_ARCH_ALL)
3380
3381STEXI
3382
3383@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
3384@findex -rtc
3385Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
3386UTC or local time, respectively. @code{localtime} is required for correct date in
3387MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
3388format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
3389
3390By default the RTC is driven by the host system time. This allows using of the
3391RTC as accurate reference clock inside the guest, specifically if the host
3392time is smoothly following an accurate external reference clock, e.g. via NTP.
3393If you want to isolate the guest time from the host, you can set @option{clock}
3394to @code{rt} instead.  To even prevent it from progressing during suspension,
3395you can set it to @code{vm}.
3396
3397Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
3398specifically with Windows' ACPI HAL. This option will try to figure out how
3399many timer interrupts were not processed by the Windows guest and will
3400re-inject them.
3401ETEXI
3402
3403DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
3404    "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>]\n" \
3405    "                enable virtual instruction counter with 2^N clock ticks per\n" \
3406    "                instruction, enable aligning the host and virtual clocks\n" \
3407    "                or disable real time cpu sleeping\n", QEMU_ARCH_ALL)
3408STEXI
3409@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename}]
3410@findex -icount
3411Enable virtual instruction counter.  The virtual cpu will execute one
3412instruction every 2^@var{N} ns of virtual time.  If @code{auto} is specified
3413then the virtual cpu speed will be automatically adjusted to keep virtual
3414time within a few seconds of real time.
3415
3416When the virtual cpu is sleeping, the virtual time will advance at default
3417speed unless @option{sleep=on|off} is specified.
3418With @option{sleep=on|off}, the virtual time will jump to the next timer deadline
3419instantly whenever the virtual cpu goes to sleep mode and will not advance
3420if no timer is enabled. This behavior give deterministic execution times from
3421the guest point of view.
3422
3423Note that while this option can give deterministic behavior, it does not
3424provide cycle accurate emulation.  Modern CPUs contain superscalar out of
3425order cores with complex cache hierarchies.  The number of instructions
3426executed often has little or no correlation with actual performance.
3427
3428@option{align=on} will activate the delay algorithm which will try
3429to synchronise the host clock and the virtual clock. The goal is to
3430have a guest running at the real frequency imposed by the shift option.
3431Whenever the guest clock is behind the host clock and if
3432@option{align=on} is specified then we print a message to the user
3433to inform about the delay.
3434Currently this option does not work when @option{shift} is @code{auto}.
3435Note: The sync algorithm will work for those shift values for which
3436the guest clock runs ahead of the host clock. Typically this happens
3437when the shift value is high (how high depends on the host machine).
3438
3439When @option{rr} option is specified deterministic record/replay is enabled.
3440Replay log is written into @var{filename} file in record mode and
3441read from this file in replay mode.
3442ETEXI
3443
3444DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
3445    "-watchdog model\n" \
3446    "                enable virtual hardware watchdog [default=none]\n",
3447    QEMU_ARCH_ALL)
3448STEXI
3449@item -watchdog @var{model}
3450@findex -watchdog
3451Create a virtual hardware watchdog device.  Once enabled (by a guest
3452action), the watchdog must be periodically polled by an agent inside
3453the guest or else the guest will be restarted. Choose a model for
3454which your guest has drivers.
3455
3456The @var{model} is the model of hardware watchdog to emulate. Use
3457@code{-watchdog help} to list available hardware models. Only one
3458watchdog can be enabled for a guest.
3459
3460The following models may be available:
3461@table @option
3462@item ib700
3463iBASE 700 is a very simple ISA watchdog with a single timer.
3464@item i6300esb
3465Intel 6300ESB I/O controller hub is a much more featureful PCI-based
3466dual-timer watchdog.
3467@item diag288
3468A virtual watchdog for s390x backed by the diagnose 288 hypercall
3469(currently KVM only).
3470@end table
3471ETEXI
3472
3473DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
3474    "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
3475    "                action when watchdog fires [default=reset]\n",
3476    QEMU_ARCH_ALL)
3477STEXI
3478@item -watchdog-action @var{action}
3479@findex -watchdog-action
3480
3481The @var{action} controls what QEMU will do when the watchdog timer
3482expires.
3483The default is
3484@code{reset} (forcefully reset the guest).
3485Other possible actions are:
3486@code{shutdown} (attempt to gracefully shutdown the guest),
3487@code{poweroff} (forcefully poweroff the guest),
3488@code{pause} (pause the guest),
3489@code{debug} (print a debug message and continue), or
3490@code{none} (do nothing).
3491
3492Note that the @code{shutdown} action requires that the guest responds
3493to ACPI signals, which it may not be able to do in the sort of
3494situations where the watchdog would have expired, and thus
3495@code{-watchdog-action shutdown} is not recommended for production use.
3496
3497Examples:
3498
3499@table @code
3500@item -watchdog i6300esb -watchdog-action pause
3501@itemx -watchdog ib700
3502@end table
3503ETEXI
3504
3505DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
3506    "-echr chr       set terminal escape character instead of ctrl-a\n",
3507    QEMU_ARCH_ALL)
3508STEXI
3509
3510@item -echr @var{numeric_ascii_value}
3511@findex -echr
3512Change the escape character used for switching to the monitor when using
3513monitor and serial sharing.  The default is @code{0x01} when using the
3514@code{-nographic} option.  @code{0x01} is equal to pressing
3515@code{Control-a}.  You can select a different character from the ascii
3516control keys where 1 through 26 map to Control-a through Control-z.  For
3517instance you could use the either of the following to change the escape
3518character to Control-t.
3519@table @code
3520@item -echr 0x14
3521@itemx -echr 20
3522@end table
3523ETEXI
3524
3525DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
3526    "-virtioconsole c\n" \
3527    "                set virtio console\n", QEMU_ARCH_ALL)
3528STEXI
3529@item -virtioconsole @var{c}
3530@findex -virtioconsole
3531Set virtio console.
3532
3533This option is maintained for backward compatibility.
3534
3535Please use @code{-device virtconsole} for the new way of invocation.
3536ETEXI
3537
3538DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
3539    "-show-cursor    show cursor\n", QEMU_ARCH_ALL)
3540STEXI
3541@item -show-cursor
3542@findex -show-cursor
3543Show cursor.
3544ETEXI
3545
3546DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
3547    "-tb-size n      set TB size\n", QEMU_ARCH_ALL)
3548STEXI
3549@item -tb-size @var{n}
3550@findex -tb-size
3551Set TB size.
3552ETEXI
3553
3554DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
3555    "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \
3556    "-incoming rdma:host:port[,ipv4][,ipv6]\n" \
3557    "-incoming unix:socketpath\n" \
3558    "                prepare for incoming migration, listen on\n" \
3559    "                specified protocol and socket address\n" \
3560    "-incoming fd:fd\n" \
3561    "-incoming exec:cmdline\n" \
3562    "                accept incoming migration on given file descriptor\n" \
3563    "                or from given external command\n" \
3564    "-incoming defer\n" \
3565    "                wait for the URI to be specified via migrate_incoming\n",
3566    QEMU_ARCH_ALL)
3567STEXI
3568@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6]
3569@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6]
3570@findex -incoming
3571Prepare for incoming migration, listen on a given tcp port.
3572
3573@item -incoming unix:@var{socketpath}
3574Prepare for incoming migration, listen on a given unix socket.
3575
3576@item -incoming fd:@var{fd}
3577Accept incoming migration from a given filedescriptor.
3578
3579@item -incoming exec:@var{cmdline}
3580Accept incoming migration as an output from specified external command.
3581
3582@item -incoming defer
3583Wait for the URI to be specified via migrate_incoming.  The monitor can
3584be used to change settings (such as migration parameters) prior to issuing
3585the migrate_incoming to allow the migration to begin.
3586ETEXI
3587
3588DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
3589    "-nodefaults     don't create default devices\n", QEMU_ARCH_ALL)
3590STEXI
3591@item -nodefaults
3592@findex -nodefaults
3593Don't create default devices. Normally, QEMU sets the default devices like serial
3594port, parallel port, virtual console, monitor device, VGA adapter, floppy and
3595CD-ROM drive and others. The @code{-nodefaults} option will disable all those
3596default devices.
3597ETEXI
3598
3599#ifndef _WIN32
3600DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
3601    "-chroot dir     chroot to dir just before starting the VM\n",
3602    QEMU_ARCH_ALL)
3603#endif
3604STEXI
3605@item -chroot @var{dir}
3606@findex -chroot
3607Immediately before starting guest execution, chroot to the specified
3608directory.  Especially useful in combination with -runas.
3609ETEXI
3610
3611#ifndef _WIN32
3612DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
3613    "-runas user     change to user id user just before starting the VM\n",
3614    QEMU_ARCH_ALL)
3615#endif
3616STEXI
3617@item -runas @var{user}
3618@findex -runas
3619Immediately before starting guest execution, drop root privileges, switching
3620to the specified user.
3621ETEXI
3622
3623DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
3624    "-prom-env variable=value\n"
3625    "                set OpenBIOS nvram variables\n",
3626    QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3627STEXI
3628@item -prom-env @var{variable}=@var{value}
3629@findex -prom-env
3630Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
3631ETEXI
3632DEF("semihosting", 0, QEMU_OPTION_semihosting,
3633    "-semihosting    semihosting mode\n",
3634    QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3635    QEMU_ARCH_MIPS)
3636STEXI
3637@item -semihosting
3638@findex -semihosting
3639Enable semihosting mode (ARM, M68K, Xtensa, MIPS only).
3640ETEXI
3641DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config,
3642    "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \
3643    "                semihosting configuration\n",
3644QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3645QEMU_ARCH_MIPS)
3646STEXI
3647@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]
3648@findex -semihosting-config
3649Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only).
3650@table @option
3651@item target=@code{native|gdb|auto}
3652Defines where the semihosting calls will be addressed, to QEMU (@code{native})
3653or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb}
3654during debug sessions and @code{native} otherwise.
3655@item arg=@var{str1},arg=@var{str2},...
3656Allows the user to pass input arguments, and can be used multiple times to build
3657up a list. The old-style @code{-kernel}/@code{-append} method of passing a
3658command line is still supported for backward compatibility. If both the
3659@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are
3660specified, the former is passed to semihosting as it always takes precedence.
3661@end table
3662ETEXI
3663DEF("old-param", 0, QEMU_OPTION_old_param,
3664    "-old-param      old param mode\n", QEMU_ARCH_ARM)
3665STEXI
3666@item -old-param
3667@findex -old-param (ARM)
3668Old param mode (ARM only).
3669ETEXI
3670
3671DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
3672    "-sandbox <arg>  Enable seccomp mode 2 system call filter (default 'off').\n",
3673    QEMU_ARCH_ALL)
3674STEXI
3675@item -sandbox @var{arg}
3676@findex -sandbox
3677Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
3678disable it.  The default is 'off'.
3679ETEXI
3680
3681DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
3682    "-readconfig <file>\n", QEMU_ARCH_ALL)
3683STEXI
3684@item -readconfig @var{file}
3685@findex -readconfig
3686Read device configuration from @var{file}. This approach is useful when you want to spawn
3687QEMU process with many command line options but you don't want to exceed the command line
3688character limit.
3689ETEXI
3690DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
3691    "-writeconfig <file>\n"
3692    "                read/write config file\n", QEMU_ARCH_ALL)
3693STEXI
3694@item -writeconfig @var{file}
3695@findex -writeconfig
3696Write device configuration to @var{file}. The @var{file} can be either filename to save
3697command line and device configuration into file or dash @code{-}) character to print the
3698output to stdout. This can be later used as input file for @code{-readconfig} option.
3699ETEXI
3700DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig,
3701    "-nodefconfig\n"
3702    "                do not load default config files at startup\n",
3703    QEMU_ARCH_ALL)
3704STEXI
3705@item -nodefconfig
3706@findex -nodefconfig
3707Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
3708The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
3709ETEXI
3710DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
3711    "-no-user-config\n"
3712    "                do not load user-provided config files at startup\n",
3713    QEMU_ARCH_ALL)
3714STEXI
3715@item -no-user-config
3716@findex -no-user-config
3717The @code{-no-user-config} option makes QEMU not load any of the user-provided
3718config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config
3719files from @var{datadir}.
3720ETEXI
3721DEF("trace", HAS_ARG, QEMU_OPTION_trace,
3722    "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n"
3723    "                specify tracing options\n",
3724    QEMU_ARCH_ALL)
3725STEXI
3726HXCOMM This line is not accurate, as some sub-options are backend-specific but
3727HXCOMM HX does not support conditional compilation of text.
3728@item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}]
3729@findex -trace
3730@include qemu-option-trace.texi
3731ETEXI
3732
3733HXCOMM Internal use
3734DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL)
3735DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL)
3736
3737#ifdef __linux__
3738DEF("enable-fips", 0, QEMU_OPTION_enablefips,
3739    "-enable-fips    enable FIPS 140-2 compliance\n",
3740    QEMU_ARCH_ALL)
3741#endif
3742STEXI
3743@item -enable-fips
3744@findex -enable-fips
3745Enable FIPS 140-2 compliance mode.
3746ETEXI
3747
3748HXCOMM Deprecated by -machine accel=tcg property
3749DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386)
3750
3751HXCOMM Deprecated by kvm-pit driver properties
3752DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection,
3753    "", QEMU_ARCH_I386)
3754
3755HXCOMM Deprecated (ignored)
3756DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386)
3757
3758HXCOMM Deprecated by -machine kernel_irqchip=on|off property
3759DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386)
3760
3761HXCOMM Deprecated (ignored)
3762DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL)
3763
3764DEF("msg", HAS_ARG, QEMU_OPTION_msg,
3765    "-msg timestamp[=on|off]\n"
3766    "                change the format of messages\n"
3767    "                on|off controls leading timestamps (default:on)\n",
3768    QEMU_ARCH_ALL)
3769STEXI
3770@item -msg timestamp[=on|off]
3771@findex -msg
3772prepend a timestamp to each log message.(default:on)
3773ETEXI
3774
3775DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate,
3776    "-dump-vmstate <file>\n"
3777    "                Output vmstate information in JSON format to file.\n"
3778    "                Use the scripts/vmstate-static-checker.py file to\n"
3779    "                check for possible regressions in migration code\n"
3780    "                by comparing two such vmstate dumps.\n",
3781    QEMU_ARCH_ALL)
3782STEXI
3783@item -dump-vmstate @var{file}
3784@findex -dump-vmstate
3785Dump json-encoded vmstate information for current machine type to file
3786in @var{file}
3787ETEXI
3788
3789STEXI
3790@end table
3791ETEXI
3792DEFHEADING()
3793DEFHEADING(Generic object creation)
3794STEXI
3795@table @option
3796ETEXI
3797
3798DEF("object", HAS_ARG, QEMU_OPTION_object,
3799    "-object TYPENAME[,PROP1=VALUE1,...]\n"
3800    "                create a new object of type TYPENAME setting properties\n"
3801    "                in the order they are specified.  Note that the 'id'\n"
3802    "                property must be set.  These objects are placed in the\n"
3803    "                '/objects' path.\n",
3804    QEMU_ARCH_ALL)
3805STEXI
3806@item -object @var{typename}[,@var{prop1}=@var{value1},...]
3807@findex -object
3808Create a new object of type @var{typename} setting properties
3809in the order they are specified.  Note that the 'id'
3810property must be set.  These objects are placed in the
3811'/objects' path.
3812
3813@table @option
3814
3815@item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off}
3816
3817Creates a memory file backend object, which can be used to back
3818the guest RAM with huge pages. The @option{id} parameter is a
3819unique ID that will be used to reference this memory region
3820when configuring the @option{-numa} argument. The @option{size}
3821option provides the size of the memory region, and accepts
3822common suffixes, eg @option{500M}. The @option{mem-path} provides
3823the path to either a shared memory or huge page filesystem mount.
3824The @option{share} boolean option determines whether the memory
3825region is marked as private to QEMU, or shared. The latter allows
3826a co-operating external process to access the QEMU memory region.
3827
3828@item -object rng-random,id=@var{id},filename=@var{/dev/random}
3829
3830Creates a random number generator backend which obtains entropy from
3831a device on the host. The @option{id} parameter is a unique ID that
3832will be used to reference this entropy backend from the @option{virtio-rng}
3833device. The @option{filename} parameter specifies which file to obtain
3834entropy from and if omitted defaults to @option{/dev/random}.
3835
3836@item -object rng-egd,id=@var{id},chardev=@var{chardevid}
3837
3838Creates a random number generator backend which obtains entropy from
3839an external daemon running on the host. The @option{id} parameter is
3840a unique ID that will be used to reference this entropy backend from
3841the @option{virtio-rng} device. The @option{chardev} parameter is
3842the unique ID of a character device backend that provides the connection
3843to the RNG daemon.
3844
3845@item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off}
3846
3847Creates a TLS anonymous credentials object, which can be used to provide
3848TLS support on network backends. The @option{id} parameter is a unique
3849ID which network backends will use to access the credentials. The
3850@option{endpoint} is either @option{server} or @option{client} depending
3851on whether the QEMU network backend that uses the credentials will be
3852acting as a client or as a server. If @option{verify-peer} is enabled
3853(the default) then once the handshake is completed, the peer credentials
3854will be verified, though this is a no-op for anonymous credentials.
3855
3856The @var{dir} parameter tells QEMU where to find the credential
3857files. For server endpoints, this directory may contain a file
3858@var{dh-params.pem} providing diffie-hellman parameters to use
3859for the TLS server. If the file is missing, QEMU will generate
3860a set of DH parameters at startup. This is a computationally
3861expensive operation that consumes random pool entropy, so it is
3862recommended that a persistent set of parameters be generated
3863upfront and saved.
3864
3865@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}
3866
3867Creates a TLS anonymous credentials object, which can be used to provide
3868TLS support on network backends. The @option{id} parameter is a unique
3869ID which network backends will use to access the credentials. The
3870@option{endpoint} is either @option{server} or @option{client} depending
3871on whether the QEMU network backend that uses the credentials will be
3872acting as a client or as a server. If @option{verify-peer} is enabled
3873(the default) then once the handshake is completed, the peer credentials
3874will be verified. With x509 certificates, this implies that the clients
3875must be provided with valid client certificates too.
3876
3877The @var{dir} parameter tells QEMU where to find the credential
3878files. For server endpoints, this directory may contain a file
3879@var{dh-params.pem} providing diffie-hellman parameters to use
3880for the TLS server. If the file is missing, QEMU will generate
3881a set of DH parameters at startup. This is a computationally
3882expensive operation that consumes random pool entropy, so it is
3883recommended that a persistent set of parameters be generated
3884upfront and saved.
3885
3886For x509 certificate credentials the directory will contain further files
3887providing the x509 certificates. The certificates must be stored
3888in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional),
3889@var{server-cert.pem} (only servers), @var{server-key.pem} (only servers),
3890@var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients).
3891
3892For the @var{server-key.pem} and @var{client-key.pem} files which
3893contain sensitive private keys, it is possible to use an encrypted
3894version by providing the @var{passwordid} parameter. This provides
3895the ID of a previously created @code{secret} object containing the
3896password for decryption.
3897
3898@item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}]
3899
3900Interval @var{t} can't be 0, this filter batches the packet delivery: all
3901packets arriving in a given interval on netdev @var{netdevid} are delayed
3902until the end of the interval. Interval is in microseconds.
3903@option{status} is optional that indicate whether the netfilter is
3904on (enabled) or off (disabled), the default status for netfilter will be 'on'.
3905
3906queue @var{all|rx|tx} is an option that can be applied to any netfilter.
3907
3908@option{all}: the filter is attached both to the receive and the transmit
3909              queue of the netdev (default).
3910
3911@option{rx}: the filter is attached to the receive queue of the netdev,
3912             where it will receive packets sent to the netdev.
3913
3914@option{tx}: the filter is attached to the transmit queue of the netdev,
3915             where it will receive packets sent by the netdev.
3916
3917@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid}[,queue=@var{all|rx|tx}]
3918
3919filter-mirror on netdev @var{netdevid},mirror net packet to chardev
3920@var{chardevid}
3921
3922@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},
3923outdev=@var{chardevid}[,queue=@var{all|rx|tx}]
3924
3925filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev
3926@var{chardevid},and redirect indev's packet to filter.
3927Create a filter-redirector we need to differ outdev id from indev id, id can not
3928be the same. we can just use indev or outdev, but at least one of indev or outdev
3929need to be specified.
3930
3931@item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},rewriter-mode=@var{mode}[,queue=@var{all|rx|tx}]
3932
3933Filter-rewriter is a part of COLO project.It will rewrite tcp packet to
3934secondary from primary to keep secondary tcp connection,and rewrite
3935tcp packet to primary from secondary make tcp packet can be handled by
3936client.
3937
3938usage:
3939colo secondary:
3940-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
3941-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
3942-object filter-rewriter,id=rew0,netdev=hn0,queue=all
3943
3944@item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}]
3945
3946Dump the network traffic on netdev @var{dev} to the file specified by
3947@var{filename}. At most @var{len} bytes (64k by default) per packet are stored.
3948The file format is libpcap, so it can be analyzed with tools such as tcpdump
3949or Wireshark.
3950
3951@item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},
3952outdev=@var{chardevid}
3953
3954Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with
3955secondary packet. If the packets are same, we will output primary
3956packet to outdev@var{chardevid}, else we will notify colo-frame
3957do checkpoint and send primary packet to outdev@var{chardevid}.
3958
3959we must use it with the help of filter-mirror and filter-redirector.
3960
3961@example
3962
3963primary:
3964-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown
3965-device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66
3966-chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait
3967-chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait
3968-chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait
3969-chardev socket,id=compare0-0,host=3.3.3.3,port=9001
3970-chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait
3971-chardev socket,id=compare_out0,host=3.3.3.3,port=9005
3972-object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0
3973-object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out
3974-object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0
3975-object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0
3976
3977secondary:
3978-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown
3979-device e1000,netdev=hn0,mac=52:a4:00:12:78:66
3980-chardev socket,id=red0,host=3.3.3.3,port=9003
3981-chardev socket,id=red1,host=3.3.3.3,port=9004
3982-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
3983-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
3984
3985@end example
3986
3987If you want to know the detail of above command line, you can read
3988the colo-compare git log.
3989
3990@item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}]
3991
3992Creates a cryptodev backend which executes crypto opreation from
3993the QEMU cipher APIS. The @var{id} parameter is
3994a unique ID that will be used to reference this cryptodev backend from
3995the @option{virtio-crypto} device. The @var{queues} parameter is optional,
3996which specify the queue number of cryptodev backend, the default of
3997@var{queues} is 1.
3998
3999@example
4000
4001 # qemu-system-x86_64 \
4002   [...] \
4003       -object cryptodev-backend-builtin,id=cryptodev0 \
4004       -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
4005   [...]
4006@end example
4007
4008@item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4009@item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
4010
4011Defines a secret to store a password, encryption key, or some other sensitive
4012data. The sensitive data can either be passed directly via the @var{data}
4013parameter, or indirectly via the @var{file} parameter. Using the @var{data}
4014parameter is insecure unless the sensitive data is encrypted.
4015
4016The sensitive data can be provided in raw format (the default), or base64.
4017When encoded as JSON, the raw format only supports valid UTF-8 characters,
4018so base64 is recommended for sending binary data. QEMU will convert from
4019which ever format is provided to the format it needs internally. eg, an
4020RBD password can be provided in raw format, even though it will be base64
4021encoded when passed onto the RBD sever.
4022
4023For added protection, it is possible to encrypt the data associated with
4024a secret using the AES-256-CBC cipher. Use of encryption is indicated
4025by providing the @var{keyid} and @var{iv} parameters. The @var{keyid}
4026parameter provides the ID of a previously defined secret that contains
4027the AES-256 decryption key. This key should be 32-bytes long and be
4028base64 encoded. The @var{iv} parameter provides the random initialization
4029vector used for encryption of this particular secret and should be a
4030base64 encrypted string of the 16-byte IV.
4031
4032The simplest (insecure) usage is to provide the secret inline
4033
4034@example
4035
4036 # $QEMU -object secret,id=sec0,data=letmein,format=raw
4037
4038@end example
4039
4040The simplest secure usage is to provide the secret via a file
4041
4042 # echo -n "letmein" > mypasswd.txt
4043 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw
4044
4045For greater security, AES-256-CBC should be used. To illustrate usage,
4046consider the openssl command line tool which can encrypt the data. Note
4047that when encrypting, the plaintext must be padded to the cipher block
4048size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm.
4049
4050First a master key needs to be created in base64 encoding:
4051
4052@example
4053 # openssl rand -base64 32 > key.b64
4054 # KEY=$(base64 -d key.b64 | hexdump  -v -e '/1 "%02X"')
4055@end example
4056
4057Each secret to be encrypted needs to have a random initialization vector
4058generated. These do not need to be kept secret
4059
4060@example
4061 # openssl rand -base64 16 > iv.b64
4062 # IV=$(base64 -d iv.b64 | hexdump  -v -e '/1 "%02X"')
4063@end example
4064
4065The secret to be defined can now be encrypted, in this case we're
4066telling openssl to base64 encode the result, but it could be left
4067as raw bytes if desired.
4068
4069@example
4070 # SECRET=$(echo -n "letmein" |
4071            openssl enc -aes-256-cbc -a -K $KEY -iv $IV)
4072@end example
4073
4074When launching QEMU, create a master secret pointing to @code{key.b64}
4075and specify that to be used to decrypt the user password. Pass the
4076contents of @code{iv.b64} to the second secret
4077
4078@example
4079 # $QEMU \
4080     -object secret,id=secmaster0,format=base64,file=key.b64 \
4081     -object secret,id=sec0,keyid=secmaster0,format=base64,\
4082         data=$SECRET,iv=$(<iv.b64)
4083@end example
4084
4085@end table
4086
4087ETEXI
4088
4089
4090HXCOMM This is the last statement. Insert new options before this line!
4091STEXI
4092@end table
4093ETEXI
4094