1 HXCOMM Use DEFHEADING() to define headings in both help text and texi
2 HXCOMM Text between STEXI and ETEXI are copied to texi version and
3 HXCOMM discarded from C version
4 HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to
5 HXCOMM construct option structures, enums and help message for specified
7 HXCOMM HXCOMM can be used for comments, discarded from both texi and C
9 HXCOMM TODO : when we are able to change -help output without breaking
10 HXCOMM libvirt we should update the help options which refer to -cpu ?,
11 HXCOMM -driver ?, etc to use the preferred -cpu help etc instead.
13 DEFHEADING(Standard options:)
18 DEF("help", 0, QEMU_OPTION_h,
19 "-h or -help display this help and exit\n", QEMU_ARCH_ALL)
26 DEF("version", 0, QEMU_OPTION_version,
27 "-version display version information and exit\n", QEMU_ARCH_ALL)
31 Display version information and exit
34 DEF("machine", HAS_ARG, QEMU_OPTION_machine, \
35 "-machine [type=]name[,prop[=value][,...]]\n"
36 " selects emulated machine (-machine ? for list)\n"
37 " property accel=accel1[:accel2[:...]] selects accelerator\n"
38 " supported accelerators are kvm, xen, tcg (default: tcg)\n"
39 " kernel_irqchip=on|off controls accelerated irqchip support\n"
40 " kvm_shadow_mem=size of KVM shadow MMU\n"
41 " dump-guest-core=on|off include guest memory in a core dump (default=on)\n",
44 @item -machine [type=]@var{name}[,prop=@var{value}[,...]]
46 Select the emulated machine by @var{name}. Use @code{-machine ?} to list
47 available machines. Supported machine properties are:
49 @item accel=@var{accels1}[:@var{accels2}[:...]]
50 This is used to enable an accelerator. Depending on the target architecture,
51 kvm, xen, or tcg can be available. By default, tcg is used. If there is more
52 than one accelerator specified, the next one is used if the previous one fails
54 @item kernel_irqchip=on|off
55 Enables in-kernel irqchip support for the chosen accelerator when available.
56 @item kvm_shadow_mem=size
57 Defines the size of the KVM shadow MMU.
58 @item dump-guest-core=on|off
59 Include guest memory in a core dump. The default is on.
63 HXCOMM Deprecated by -machine
64 DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL)
66 DEF("cpu", HAS_ARG, QEMU_OPTION_cpu,
67 "-cpu cpu select CPU (-cpu ? for list)\n", QEMU_ARCH_ALL)
69 @item -cpu @var{model}
71 Select CPU model (-cpu ? for list and additional feature selection)
74 DEF("smp", HAS_ARG, QEMU_OPTION_smp,
75 "-smp n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n"
76 " set the number of CPUs to 'n' [default=1]\n"
77 " maxcpus= maximum number of total cpus, including\n"
78 " offline CPUs for hotplug, etc\n"
79 " cores= number of CPU cores on one socket\n"
80 " threads= number of threads on one CPU core\n"
81 " sockets= number of discrete sockets in the system\n",
84 @item -smp @var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
86 Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255
87 CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs
89 For the PC target, the number of @var{cores} per socket, the number
90 of @var{threads} per cores and the total number of @var{sockets} can be
91 specified. Missing values will be computed. If any on the three values is
92 given, the total number of CPUs @var{n} can be omitted. @var{maxcpus}
93 specifies the maximum number of hotpluggable CPUs.
96 DEF("numa", HAS_ARG, QEMU_OPTION_numa,
97 "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL)
99 @item -numa @var{opts}
101 Simulate a multi node NUMA system. If mem and cpus are omitted, resources
105 DEF("fda", HAS_ARG, QEMU_OPTION_fda,
106 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL)
107 DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL)
109 @item -fda @var{file}
110 @item -fdb @var{file}
113 Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can
114 use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}).
117 DEF("hda", HAS_ARG, QEMU_OPTION_hda,
118 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL)
119 DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL)
120 DEF("hdc", HAS_ARG, QEMU_OPTION_hdc,
121 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL)
122 DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL)
124 @item -hda @var{file}
125 @item -hdb @var{file}
126 @item -hdc @var{file}
127 @item -hdd @var{file}
132 Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}).
135 DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom,
136 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n",
139 @item -cdrom @var{file}
141 Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and
142 @option{-cdrom} at the same time). You can use the host CD-ROM by
143 using @file{/dev/cdrom} as filename (@pxref{host_drives}).
146 DEF("drive", HAS_ARG, QEMU_OPTION_drive,
147 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n"
148 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n"
149 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n"
150 " [,serial=s][,addr=A][,id=name][,aio=threads|native]\n"
151 " [,readonly=on|off][,copy-on-read=on|off]\n"
152 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]][[,iops=i]|[[,iops_rd=r][,iops_wr=w]]\n"
153 " use 'file' as a drive image\n", QEMU_ARCH_ALL)
155 @item -drive @var{option}[,@var{option}[,@var{option}[,...]]]
158 Define a new drive. Valid options are:
161 @item file=@var{file}
162 This option defines which disk image (@pxref{disk_images}) to use with
163 this drive. If the filename contains comma, you must double it
164 (for instance, "file=my,,file" to use file "my,file").
166 Special files such as iSCSI devices can be specified using protocol
167 specific URLs. See the section for "Device URL Syntax" for more information.
168 @item if=@var{interface}
169 This option defines on which type on interface the drive is connected.
170 Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio.
171 @item bus=@var{bus},unit=@var{unit}
172 These options define where is connected the drive by defining the bus number and
174 @item index=@var{index}
175 This option defines where is connected the drive by using an index in the list
176 of available connectors of a given interface type.
177 @item media=@var{media}
178 This option defines the type of the media: disk or cdrom.
179 @item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}]
180 These options have the same definition as they have in @option{-hdachs}.
181 @item snapshot=@var{snapshot}
182 @var{snapshot} is "on" or "off" and allows to enable snapshot for given drive (see @option{-snapshot}).
183 @item cache=@var{cache}
184 @var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data.
186 @var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
187 @item format=@var{format}
188 Specify which disk @var{format} will be used rather than detecting
189 the format. Can be used to specifiy format=raw to avoid interpreting
190 an untrusted format header.
191 @item serial=@var{serial}
192 This option specifies the serial number to assign to the device.
193 @item addr=@var{addr}
194 Specify the controller's PCI address (if=virtio only).
195 @item werror=@var{action},rerror=@var{action}
196 Specify which @var{action} to take on write and read errors. Valid actions are:
197 "ignore" (ignore the error and try to continue), "stop" (pause QEMU),
198 "report" (report the error to the guest), "enospc" (pause QEMU only if the
199 host disk is full; report the error to the guest otherwise).
200 The default setting is @option{werror=enospc} and @option{rerror=report}.
202 Open drive @option{file} as read-only. Guest write attempts will fail.
203 @item copy-on-read=@var{copy-on-read}
204 @var{copy-on-read} is "on" or "off" and enables whether to copy read backing
205 file sectors into the image file.
208 By default, writethrough caching is used for all block device. This means that
209 the host page cache will be used to read and write data but write notification
210 will be sent to the guest only when the data has been reported as written by
211 the storage subsystem.
213 Writeback caching will report data writes as completed as soon as the data is
214 present in the host page cache. This is safe as long as you trust your host.
215 If your host crashes or loses power, then the guest may experience data
218 The host page cache can be avoided entirely with @option{cache=none}. This will
219 attempt to do disk IO directly to the guests memory. QEMU may still perform
220 an internal copy of the data.
222 The host page cache can be avoided while only sending write notifications to
223 the guest when the data has been reported as written by the storage subsystem
224 using @option{cache=directsync}.
226 Some block drivers perform badly with @option{cache=writethrough}, most notably,
227 qcow2. If performance is more important than correctness,
228 @option{cache=writeback} should be used with qcow2.
230 In case you don't care about data integrity over host failures, use
231 cache=unsafe. This option tells QEMU that it never needs to write any data
232 to the disk but can instead keeps things in cache. If anything goes wrong,
233 like your host losing power, the disk storage getting disconnected accidentally,
234 etc. you're image will most probably be rendered unusable. When using
235 the @option{-snapshot} option, unsafe caching is always used.
237 Copy-on-read avoids accessing the same backing file sectors repeatedly and is
238 useful when the backing file is over a slow network. By default copy-on-read
241 Instead of @option{-cdrom} you can use:
243 qemu-system-i386 -drive file=file,index=2,media=cdrom
246 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
249 qemu-system-i386 -drive file=file,index=0,media=disk
250 qemu-system-i386 -drive file=file,index=1,media=disk
251 qemu-system-i386 -drive file=file,index=2,media=disk
252 qemu-system-i386 -drive file=file,index=3,media=disk
255 You can connect a CDROM to the slave of ide0:
257 qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
260 If you don't specify the "file=" argument, you define an empty drive:
262 qemu-system-i386 -drive if=ide,index=1,media=cdrom
265 You can connect a SCSI disk with unit ID 6 on the bus #0:
267 qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6
270 Instead of @option{-fda}, @option{-fdb}, you can use:
272 qemu-system-i386 -drive file=file,index=0,if=floppy
273 qemu-system-i386 -drive file=file,index=1,if=floppy
276 By default, @var{interface} is "ide" and @var{index} is automatically
279 qemu-system-i386 -drive file=a -drive file=b"
283 qemu-system-i386 -hda a -hdb b
287 DEF("set", HAS_ARG, QEMU_OPTION_set,
288 "-set group.id.arg=value\n"
289 " set <arg> parameter for item <id> of type <group>\n"
290 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL)
297 DEF("global", HAS_ARG, QEMU_OPTION_global,
298 "-global driver.prop=value\n"
299 " set a global default for a driver property\n",
302 @item -global @var{driver}.@var{prop}=@var{value}
304 Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.:
307 qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk
310 In particular, you can use this to set driver properties for devices which are
311 created automatically by the machine model. To create a device which is not
312 created automatically and set properties on it, use -@option{device}.
315 DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock,
316 "-mtdblock file use 'file' as on-board Flash memory image\n",
319 @item -mtdblock @var{file}
321 Use @var{file} as on-board Flash memory image.
324 DEF("sd", HAS_ARG, QEMU_OPTION_sd,
325 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL)
329 Use @var{file} as SecureDigital card image.
332 DEF("pflash", HAS_ARG, QEMU_OPTION_pflash,
333 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL)
335 @item -pflash @var{file}
337 Use @var{file} as a parallel flash image.
340 DEF("boot", HAS_ARG, QEMU_OPTION_boot,
341 "-boot [order=drives][,once=drives][,menu=on|off]\n"
342 " [,splash=sp_name][,splash-time=sp_time]\n"
343 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n"
344 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n"
345 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n",
348 @item -boot [order=@var{drives}][,once=@var{drives}][,menu=on|off][,splash=@var{sp_name}][,splash-time=@var{sp_time}]
350 Specify boot order @var{drives} as a string of drive letters. Valid
351 drive letters depend on the target achitecture. The x86 PC uses: a, b
352 (floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot
353 from network adapter 1-4), hard disk boot is the default. To apply a
354 particular boot order only on the first startup, specify it via
357 Interactive boot menus/prompts can be enabled via @option{menu=on} as far
358 as firmware/BIOS supports them. The default is non-interactive boot.
360 A splash picture could be passed to bios, enabling user to show it as logo,
361 when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS
362 supports them. Currently Seabios for X86 system support it.
363 limitation: The splash file could be a jpeg file or a BMP file in 24 BPP
364 format(true color). The resolution should be supported by the SVGA mode, so
365 the recommended is 320x240, 640x480, 800x640.
368 # try to boot from network first, then from hard disk
369 qemu-system-i386 -boot order=nc
370 # boot from CD-ROM first, switch back to default order after reboot
371 qemu-system-i386 -boot once=d
372 # boot with a splash picture for 5 seconds.
373 qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000
376 Note: The legacy format '-boot @var{drives}' is still supported but its
377 use is discouraged as it may be removed from future versions.
380 DEF("snapshot", 0, QEMU_OPTION_snapshot,
381 "-snapshot write to temporary files instead of disk image files\n",
386 Write to temporary files instead of disk image files. In this case,
387 the raw disk image you use is not written back. You can however force
388 the write back by pressing @key{C-a s} (@pxref{disk_images}).
391 DEF("m", HAS_ARG, QEMU_OPTION_m,
392 "-m megs set virtual RAM size to megs MB [default="
393 stringify(DEFAULT_RAM_SIZE) "]\n", QEMU_ARCH_ALL)
397 Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally,
398 a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or
399 gigabytes respectively.
402 DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
403 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL)
405 @item -mem-path @var{path}
406 Allocate guest RAM from a temporarily created file in @var{path}.
410 DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
411 "-mem-prealloc preallocate guest memory (use with -mem-path)\n",
415 Preallocate memory when using -mem-path.
419 DEF("k", HAS_ARG, QEMU_OPTION_k,
420 "-k language use keyboard layout (for example 'fr' for French)\n",
423 @item -k @var{language}
425 Use keyboard layout @var{language} (for example @code{fr} for
426 French). This option is only needed where it is not easy to get raw PC
427 keycodes (e.g. on Macs, with some X11 servers or with a VNC
428 display). You don't normally need to use it on PC/Linux or PC/Windows
431 The available layouts are:
433 ar de-ch es fo fr-ca hu ja mk no pt-br sv
434 da en-gb et fr fr-ch is lt nl pl ru th
435 de en-us fi fr-be hr it lv nl-be pt sl tr
438 The default is @code{en-us}.
442 DEF("audio-help", 0, QEMU_OPTION_audio_help,
443 "-audio-help print list of audio drivers and their options\n",
448 Will show the audio subsystem help: list of drivers, tunable
452 DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw,
453 "-soundhw c1,... enable audio support\n"
454 " and only specified sound cards (comma separated list)\n"
455 " use -soundhw ? to get the list of supported cards\n"
456 " use -soundhw all to enable all of them\n", QEMU_ARCH_ALL)
458 @item -soundhw @var{card1}[,@var{card2},...] or -soundhw all
460 Enable audio and selected sound hardware. Use ? to print all
461 available sound hardware.
464 qemu-system-i386 -soundhw sb16,adlib disk.img
465 qemu-system-i386 -soundhw es1370 disk.img
466 qemu-system-i386 -soundhw ac97 disk.img
467 qemu-system-i386 -soundhw hda disk.img
468 qemu-system-i386 -soundhw all disk.img
469 qemu-system-i386 -soundhw ?
472 Note that Linux's i810_audio OSS kernel (for AC97) module might
473 require manually specifying clocking.
476 modprobe i810_audio clocking=48000
480 DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
481 "-balloon none disable balloon device\n"
482 "-balloon virtio[,addr=str]\n"
483 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL)
487 Disable balloon device.
488 @item -balloon virtio[,addr=@var{addr}]
489 Enable virtio balloon device (default), optionally with PCI address
497 DEF("usb", 0, QEMU_OPTION_usb,
498 "-usb enable the USB driver (will be the default soon)\n",
506 Enable the USB driver (will be the default soon)
509 DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice,
510 "-usbdevice name add the host or guest USB device 'name'\n",
514 @item -usbdevice @var{devname}
516 Add the USB device @var{devname}. @xref{usb_devices}.
521 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
524 Pointer device that uses absolute coordinates (like a touchscreen). This
525 means QEMU is able to report the mouse position without having to grab the
526 mouse. Also overrides the PS/2 mouse emulation when activated.
528 @item disk:[format=@var{format}]:@var{file}
529 Mass storage device based on file. The optional @var{format} argument
530 will be used rather than detecting the format. Can be used to specifiy
531 @code{format=raw} to avoid interpreting an untrusted format header.
533 @item host:@var{bus}.@var{addr}
534 Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
536 @item host:@var{vendor_id}:@var{product_id}
537 Pass through the host device identified by @var{vendor_id}:@var{product_id}
540 @item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
541 Serial converter to host character device @var{dev}, see @code{-serial} for the
545 Braille device. This will use BrlAPI to display the braille output on a real
548 @item net:@var{options}
549 Network adapter that supports CDC ethernet and RNDIS protocols.
554 DEF("device", HAS_ARG, QEMU_OPTION_device,
555 "-device driver[,prop[=value][,...]]\n"
556 " add device (based on driver)\n"
557 " prop=value,... sets driver properties\n"
558 " use -device ? to print all possible drivers\n"
559 " use -device driver,? to print all possible properties\n",
562 @item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
564 Add device @var{driver}. @var{prop}=@var{value} sets driver
565 properties. Valid properties depend on the driver. To get help on
566 possible drivers and properties, use @code{-device ?} and
567 @code{-device @var{driver},?}.
572 DEFHEADING(File system options:)
574 DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev,
575 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
576 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
581 @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}]
583 Define a new file system device. Valid options are:
586 This option specifies the fs driver backend to use.
587 Currently "local", "handle" and "proxy" file system drivers are supported.
589 Specifies identifier for this device
590 @item path=@var{path}
591 Specifies the export path for the file system device. Files under
592 this path will be available to the 9p client on the guest.
593 @item security_model=@var{security_model}
594 Specifies the security model to be used for this export path.
595 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
596 In "passthrough" security model, files are stored using the same
597 credentials as they are created on the guest. This requires QEMU
598 to run as root. In "mapped-xattr" security model, some of the file
599 attributes like uid, gid, mode bits and link target are stored as
600 file attributes. For "mapped-file" these attributes are stored in the
601 hidden .virtfs_metadata directory. Directories exported by this security model cannot
602 interact with other unix tools. "none" security model is same as
603 passthrough except the sever won't report failures if it fails to
604 set file attributes like ownership. Security model is mandatory
605 only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
606 security model as a parameter.
607 @item writeout=@var{writeout}
608 This is an optional argument. The only supported value is "immediate".
609 This means that host page cache will be used to read and write data but
610 write notification will be sent to the guest only when the data has been
611 reported as written by the storage subsystem.
613 Enables exporting 9p share as a readonly mount for guests. By default
614 read-write access is given.
615 @item socket=@var{socket}
616 Enables proxy filesystem driver to use passed socket file for communicating
617 with virtfs-proxy-helper
618 @item sock_fd=@var{sock_fd}
619 Enables proxy filesystem driver to use passed socket descriptor for
620 communicating with virtfs-proxy-helper. Usually a helper like libvirt
621 will create socketpair and pass one of the fds as sock_fd
624 -fsdev option is used along with -device driver "virtio-9p-pci".
625 @item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
626 Options for virtio-9p-pci driver are:
629 Specifies the id value specified along with -fsdev option
630 @item mount_tag=@var{mount_tag}
631 Specifies the tag name to be used by the guest to mount this export point
638 DEFHEADING(Virtual File system pass-through options:)
640 DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs,
641 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
642 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n",
647 @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}]
650 The general form of a Virtual File system pass-through options are:
653 This option specifies the fs driver backend to use.
654 Currently "local", "handle" and "proxy" file system drivers are supported.
656 Specifies identifier for this device
657 @item path=@var{path}
658 Specifies the export path for the file system device. Files under
659 this path will be available to the 9p client on the guest.
660 @item security_model=@var{security_model}
661 Specifies the security model to be used for this export path.
662 Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none".
663 In "passthrough" security model, files are stored using the same
664 credentials as they are created on the guest. This requires QEMU
665 to run as root. In "mapped-xattr" security model, some of the file
666 attributes like uid, gid, mode bits and link target are stored as
667 file attributes. For "mapped-file" these attributes are stored in the
668 hidden .virtfs_metadata directory. Directories exported by this security model cannot
669 interact with other unix tools. "none" security model is same as
670 passthrough except the sever won't report failures if it fails to
671 set file attributes like ownership. Security model is mandatory only
672 for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
673 model as a parameter.
674 @item writeout=@var{writeout}
675 This is an optional argument. The only supported value is "immediate".
676 This means that host page cache will be used to read and write data but
677 write notification will be sent to the guest only when the data has been
678 reported as written by the storage subsystem.
680 Enables exporting 9p share as a readonly mount for guests. By default
681 read-write access is given.
682 @item socket=@var{socket}
683 Enables proxy filesystem driver to use passed socket file for
684 communicating with virtfs-proxy-helper. Usually a helper like libvirt
685 will create socketpair and pass one of the fds as sock_fd
687 Enables proxy filesystem driver to use passed 'sock_fd' as the socket
688 descriptor for interfacing with virtfs-proxy-helper
692 DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth,
693 "-virtfs_synth Create synthetic file system image\n",
697 @findex -virtfs_synth
698 Create synthetic file system image
703 DEF("name", HAS_ARG, QEMU_OPTION_name,
704 "-name string1[,process=string2]\n"
705 " set the name of the guest\n"
706 " string1 sets the window title and string2 the process name (on Linux)\n",
709 @item -name @var{name}
711 Sets the @var{name} of the guest.
712 This name will be displayed in the SDL window caption.
713 The @var{name} will also be used for the VNC server.
714 Also optionally set the top visible process name in Linux.
717 DEF("uuid", HAS_ARG, QEMU_OPTION_uuid,
718 "-uuid %08x-%04x-%04x-%04x-%012x\n"
719 " specify machine UUID\n", QEMU_ARCH_ALL)
721 @item -uuid @var{uuid}
732 DEFHEADING(Display options:)
738 DEF("display", HAS_ARG, QEMU_OPTION_display,
739 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n"
740 " [,window_close=on|off]|curses|none|\n"
741 " vnc=<display>[,<optargs>]\n"
742 " select display type\n", QEMU_ARCH_ALL)
744 @item -display @var{type}
746 Select type of display to use. This option is a replacement for the
747 old style -sdl/-curses/... options. Valid values for @var{type} are
750 Display video output via SDL (usually in a separate graphics
751 window; see the SDL documentation for other possibilities).
753 Display video output via curses. For graphics device models which
754 support a text mode, QEMU can display this output using a
755 curses/ncurses interface. Nothing is displayed when the graphics
756 device is in graphical mode or if the graphics device does not support
757 a text mode. Generally only the VGA device models support text mode.
759 Do not display video output. The guest will still see an emulated
760 graphics card, but its output will not be displayed to the QEMU
761 user. This option differs from the -nographic option in that it
762 only affects what is done with video output; -nographic also changes
763 the destination of the serial and parallel port data.
765 Start a VNC server on display <arg>
769 DEF("nographic", 0, QEMU_OPTION_nographic,
770 "-nographic disable graphical output and redirect serial I/Os to console\n",
775 Normally, QEMU uses SDL to display the VGA output. With this option,
776 you can totally disable graphical output so that QEMU is a simple
777 command line application. The emulated serial port is redirected on
778 the console. Therefore, you can still use QEMU to debug a Linux kernel
779 with a serial console.
782 DEF("curses", 0, QEMU_OPTION_curses,
783 "-curses use a curses/ncurses interface instead of SDL\n",
788 Normally, QEMU uses SDL to display the VGA output. With this option,
789 QEMU can display the VGA output when in text mode using a
790 curses/ncurses interface. Nothing is displayed in graphical mode.
793 DEF("no-frame", 0, QEMU_OPTION_no_frame,
794 "-no-frame open SDL window without a frame and window decorations\n",
799 Do not use decorations for SDL windows and start them using the whole
800 available screen space. This makes the using QEMU in a dedicated desktop
801 workspace more convenient.
804 DEF("alt-grab", 0, QEMU_OPTION_alt_grab,
805 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n",
810 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
811 affects the special keys (for fullscreen, monitor-mode switching, etc).
814 DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab,
815 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n",
820 Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
821 affects the special keys (for fullscreen, monitor-mode switching, etc).
824 DEF("no-quit", 0, QEMU_OPTION_no_quit,
825 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL)
829 Disable SDL window close capability.
832 DEF("sdl", 0, QEMU_OPTION_sdl,
833 "-sdl enable SDL\n", QEMU_ARCH_ALL)
840 DEF("spice", HAS_ARG, QEMU_OPTION_spice,
841 "-spice <args> enable spice\n", QEMU_ARCH_ALL)
843 @item -spice @var{option}[,@var{option}[,...]]
845 Enable the spice remote desktop protocol. Valid options are
850 Set the TCP port spice is listening on for plaintext channels.
853 Set the IP address spice is listening on. Default is any address.
857 Force using the specified IP version.
859 @item password=<secret>
860 Set the password you need to authenticate.
863 Require that the client use SASL to authenticate with the spice.
864 The exact choice of authentication method used is controlled from the
865 system / user's SASL configuration file for the 'qemu' service. This
866 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
867 unprivileged user, an environment variable SASL_CONF_PATH can be used
868 to make it search alternate locations for the service config.
869 While some SASL auth methods can also provide data encryption (eg GSSAPI),
870 it is recommended that SASL always be combined with the 'tls' and
871 'x509' settings to enable use of SSL and server certificates. This
872 ensures a data encryption preventing compromise of authentication
875 @item disable-ticketing
876 Allow client connects without authentication.
878 @item disable-copy-paste
879 Disable copy paste between the client and the guest.
882 Set the TCP port spice is listening on for encrypted channels.
885 Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
887 @item x509-key-file=<file>
888 @item x509-key-password=<file>
889 @item x509-cert-file=<file>
890 @item x509-cacert-file=<file>
891 @item x509-dh-key-file=<file>
892 The x509 file names can also be configured individually.
894 @item tls-ciphers=<list>
895 Specify which ciphers to use.
897 @item tls-channel=[main|display|cursor|inputs|record|playback]
898 @item plaintext-channel=[main|display|cursor|inputs|record|playback]
899 Force specific channel to be used with or without TLS encryption. The
900 options can be specified multiple times to configure multiple
901 channels. The special name "default" can be used to set the default
902 mode. For channels which are not explicitly forced into one mode the
903 spice client is allowed to pick tls/plaintext as he pleases.
905 @item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
906 Configure image compression (lossless).
909 @item jpeg-wan-compression=[auto|never|always]
910 @item zlib-glz-wan-compression=[auto|never|always]
911 Configure wan image compression (lossy for slow links).
914 @item streaming-video=[off|all|filter]
915 Configure video stream detection. Default is filter.
917 @item agent-mouse=[on|off]
918 Enable/disable passing mouse events via vdagent. Default is on.
920 @item playback-compression=[on|off]
921 Enable/disable audio stream compression (using celt 0.5.1). Default is on.
923 @item seamless-migration=[on|off]
924 Enable/disable spice seamless migration. Default is off.
929 DEF("portrait", 0, QEMU_OPTION_portrait,
930 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n",
935 Rotate graphical output 90 deg left (only PXA LCD).
938 DEF("rotate", HAS_ARG, QEMU_OPTION_rotate,
939 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n",
944 Rotate graphical output some deg left (only PXA LCD).
947 DEF("vga", HAS_ARG, QEMU_OPTION_vga,
948 "-vga [std|cirrus|vmware|qxl|xenfb|none]\n"
949 " select video card type\n", QEMU_ARCH_ALL)
951 @item -vga @var{type}
953 Select type of VGA card to emulate. Valid values for @var{type} are
956 Cirrus Logic GD5446 Video card. All Windows versions starting from
957 Windows 95 should recognize and use this graphic card. For optimal
958 performances, use 16 bit color depth in the guest and the host OS.
959 (This one is the default)
961 Standard VGA card with Bochs VBE extensions. If your guest OS
962 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
963 to use high resolution modes (>= 1280x1024x16) then you should use
966 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
967 recent XFree86/XOrg server or Windows guest with a driver for this
970 QXL paravirtual graphic card. It is VGA compatible (including VESA
971 2.0 VBE support). Works best with qxl guest drivers installed though.
972 Recommended choice when using the spice protocol.
978 DEF("full-screen", 0, QEMU_OPTION_full_screen,
979 "-full-screen start in full screen\n", QEMU_ARCH_ALL)
983 Start in full screen.
986 DEF("g", 1, QEMU_OPTION_g ,
987 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n",
988 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
990 @item -g @var{width}x@var{height}[x@var{depth}]
992 Set the initial graphical resolution and depth (PPC, SPARC only).
995 DEF("vnc", HAS_ARG, QEMU_OPTION_vnc ,
996 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL)
998 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1000 Normally, QEMU uses SDL to display the VGA output. With this option,
1001 you can have QEMU listen on VNC display @var{display} and redirect the VGA
1002 display over the VNC session. It is very useful to enable the usb
1003 tablet device when using this option (option @option{-usbdevice
1004 tablet}). When using the VNC display, you must use the @option{-k}
1005 parameter to set the keyboard layout if you are not using en-us. Valid
1006 syntax for the @var{display} is
1010 @item @var{host}:@var{d}
1012 TCP connections will only be allowed from @var{host} on display @var{d}.
1013 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1014 be omitted in which case the server will accept connections from any host.
1016 @item unix:@var{path}
1018 Connections will be allowed over UNIX domain sockets where @var{path} is the
1019 location of a unix socket to listen for connections on.
1023 VNC is initialized but not started. The monitor @code{change} command
1024 can be used to later start the VNC server.
1028 Following the @var{display} value there may be one or more @var{option} flags
1029 separated by commas. Valid options are
1035 Connect to a listening VNC client via a ``reverse'' connection. The
1036 client is specified by the @var{display}. For reverse network
1037 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1038 is a TCP port number, not a display number.
1042 Require that password based authentication is used for client connections.
1044 The password must be set separately using the @code{set_password} command in
1045 the @ref{pcsys_monitor}. The syntax to change your password is:
1046 @code{set_password <protocol> <password>} where <protocol> could be either
1049 If you would like to change <protocol> password expiration, you should use
1050 @code{expire_password <protocol> <expiration-time>} where expiration time could
1051 be one of the following options: now, never, +seconds or UNIX time of
1052 expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1053 to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this
1056 You can also use keywords "now" or "never" for the expiration time to
1057 allow <protocol> password to expire immediately or never expire.
1061 Require that client use TLS when communicating with the VNC server. This
1062 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1063 attack. It is recommended that this option be combined with either the
1064 @option{x509} or @option{x509verify} options.
1066 @item x509=@var{/path/to/certificate/dir}
1068 Valid if @option{tls} is specified. Require that x509 credentials are used
1069 for negotiating the TLS session. The server will send its x509 certificate
1070 to the client. It is recommended that a password be set on the VNC server
1071 to provide authentication of the client when this is used. The path following
1072 this option specifies where the x509 certificates are to be loaded from.
1073 See the @ref{vnc_security} section for details on generating certificates.
1075 @item x509verify=@var{/path/to/certificate/dir}
1077 Valid if @option{tls} is specified. Require that x509 credentials are used
1078 for negotiating the TLS session. The server will send its x509 certificate
1079 to the client, and request that the client send its own x509 certificate.
1080 The server will validate the client's certificate against the CA certificate,
1081 and reject clients when validation fails. If the certificate authority is
1082 trusted, this is a sufficient authentication mechanism. You may still wish
1083 to set a password on the VNC server as a second authentication layer. The
1084 path following this option specifies where the x509 certificates are to
1085 be loaded from. See the @ref{vnc_security} section for details on generating
1090 Require that the client use SASL to authenticate with the VNC server.
1091 The exact choice of authentication method used is controlled from the
1092 system / user's SASL configuration file for the 'qemu' service. This
1093 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1094 unprivileged user, an environment variable SASL_CONF_PATH can be used
1095 to make it search alternate locations for the service config.
1096 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1097 it is recommended that SASL always be combined with the 'tls' and
1098 'x509' settings to enable use of SSL and server certificates. This
1099 ensures a data encryption preventing compromise of authentication
1100 credentials. See the @ref{vnc_security} section for details on using
1101 SASL authentication.
1105 Turn on access control lists for checking of the x509 client certificate
1106 and SASL party. For x509 certs, the ACL check is made against the
1107 certificate's distinguished name. This is something that looks like
1108 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1109 made against the username, which depending on the SASL plugin, may
1110 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1111 When the @option{acl} flag is set, the initial access list will be
1112 empty, with a @code{deny} policy. Thus no one will be allowed to
1113 use the VNC server until the ACLs have been loaded. This can be
1114 achieved using the @code{acl} monitor command.
1118 Enable lossy compression methods (gradient, JPEG, ...). If this
1119 option is set, VNC client may receive lossy framebuffer updates
1120 depending on its encoding settings. Enabling this option can save
1121 a lot of bandwidth at the expense of quality.
1125 Disable adaptive encodings. Adaptive encodings are enabled by default.
1126 An adaptive encoding will try to detect frequently updated screen regions,
1127 and send updates in these regions using a lossy encoding (like JPEG).
1128 This can be really helpful to save bandwidth when playing videos. Disabling
1129 adaptive encodings allows to restore the original static behavior of encodings
1132 @item share=[allow-exclusive|force-shared|ignore]
1134 Set display sharing policy. 'allow-exclusive' allows clients to ask
1135 for exclusive access. As suggested by the rfb spec this is
1136 implemented by dropping other connections. Connecting multiple
1137 clients in parallel requires all clients asking for a shared session
1138 (vncviewer: -shared switch). This is the default. 'force-shared'
1139 disables exclusive client access. Useful for shared desktop sessions,
1140 where you don't want someone forgetting specify -shared disconnect
1141 everybody else. 'ignore' completely ignores the shared flag and
1142 allows everybody connect unconditionally. Doesn't conform to the rfb
1143 spec but is traditional QEMU behavior.
1152 ARCHHEADING(, QEMU_ARCH_I386)
1154 ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1159 DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack,
1160 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n",
1165 Use it when installing Windows 2000 to avoid a disk full bug. After
1166 Windows 2000 is installed, you no longer need this option (this option
1167 slows down the IDE transfers).
1170 HXCOMM Deprecated by -rtc
1171 DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386)
1173 DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk,
1174 "-no-fd-bootchk disable boot signature checking for floppy disks\n",
1177 @item -no-fd-bootchk
1178 @findex -no-fd-bootchk
1179 Disable boot signature checking for floppy disks in Bochs BIOS. It may
1180 be needed to boot from old floppy disks.
1181 TODO: check reference to Bochs BIOS.
1184 DEF("no-acpi", 0, QEMU_OPTION_no_acpi,
1185 "-no-acpi disable ACPI\n", QEMU_ARCH_I386)
1189 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1190 it if your guest OS complains about ACPI problems (PC target machine
1194 DEF("no-hpet", 0, QEMU_OPTION_no_hpet,
1195 "-no-hpet disable HPET\n", QEMU_ARCH_I386)
1199 Disable HPET support.
1202 DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable,
1203 "-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"
1204 " ACPI table description\n", QEMU_ARCH_I386)
1206 @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}]...]
1208 Add ACPI table with specified header fields and context from specified files.
1209 For file=, take whole ACPI table from the specified files, including all
1210 ACPI headers (possible overridden by other options).
1211 For data=, only data
1212 portion of the table is used, all header information is specified in the
1216 DEF("smbios", HAS_ARG, QEMU_OPTION_smbios,
1217 "-smbios file=binary\n"
1218 " load SMBIOS entry from binary file\n"
1219 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n"
1220 " specify SMBIOS type 0 fields\n"
1221 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n"
1222 " [,uuid=uuid][,sku=str][,family=str]\n"
1223 " specify SMBIOS type 1 fields\n", QEMU_ARCH_I386)
1225 @item -smbios file=@var{binary}
1227 Load SMBIOS entry from binary file.
1229 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}]
1231 Specify SMBIOS type 0 fields
1233 @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}]
1234 Specify SMBIOS type 1 fields
1242 DEFHEADING(Network options:)
1247 HXCOMM Legacy slirp options (now moved to -net user):
1249 DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL)
1250 DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL)
1251 DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL)
1253 DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL)
1257 DEF("net", HAS_ARG, QEMU_OPTION_net,
1258 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n"
1259 " create a new Network Interface Card and connect it to VLAN 'n'\n"
1261 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=on|off]\n"
1262 " [,hostname=host][,dhcpstart=addr][,dns=addr][,tftp=dir][,bootfile=f]\n"
1263 " [,hostfwd=rule][,guestfwd=rule]"
1265 "[,smb=dir[,smbserver=addr]]\n"
1267 " connect the user mode network stack to VLAN 'n', configure its\n"
1268 " DHCP server and enabled optional services\n"
1271 "-net tap[,vlan=n][,name=str],ifname=name\n"
1272 " connect the host TAP network interface to VLAN 'n'\n"
1274 "-net tap[,vlan=n][,name=str][,fd=h][,ifname=name][,script=file][,downscript=dfile][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off][,vhostfd=h][,vhostforce=on|off]\n"
1275 " connect the host TAP network interface to VLAN 'n' \n"
1276 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n"
1277 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n"
1278 " to deconfigure it\n"
1279 " use '[down]script=no' to disable script execution\n"
1280 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n"
1282 " use 'fd=h' to connect to an already opened TAP interface\n"
1283 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n"
1284 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n"
1285 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n"
1286 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n"
1287 " use vhost=on to enable experimental in kernel accelerator\n"
1288 " (only has effect for virtio guests which use MSIX)\n"
1289 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n"
1290 " use 'vhostfd=h' to connect to an already opened vhost net device\n"
1291 "-net bridge[,vlan=n][,name=str][,br=bridge][,helper=helper]\n"
1292 " connects a host TAP network interface to a host bridge device 'br'\n"
1293 " (default=" DEFAULT_BRIDGE_INTERFACE ") using the program 'helper'\n"
1294 " (default=" DEFAULT_BRIDGE_HELPER ")\n"
1296 "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n"
1297 " connect the vlan 'n' to another VLAN using a socket connection\n"
1298 "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port[,localaddr=addr]]\n"
1299 " connect the vlan 'n' to multicast maddr and port\n"
1300 " use 'localaddr=addr' to specify the host address to send packets from\n"
1301 "-net socket[,vlan=n][,name=str][,fd=h][,udp=host:port][,localaddr=host:port]\n"
1302 " connect the vlan 'n' to another VLAN using an UDP tunnel\n"
1304 "-net vde[,vlan=n][,name=str][,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
1305 " connect the vlan 'n' to port 'n' of a vde switch running\n"
1306 " on host and listening for incoming connections on 'socketpath'.\n"
1307 " Use group 'groupname' and mode 'octalmode' to change default\n"
1308 " ownership and permissions for communication port.\n"
1310 "-net dump[,vlan=n][,file=f][,len=n]\n"
1311 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n"
1312 "-net none use it alone to have zero network devices. If no -net option\n"
1313 " is provided, the default is '-net nic -net user'\n", QEMU_ARCH_ALL)
1314 DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
1324 "socket],id=str[,option][,option][,...]\n", QEMU_ARCH_ALL)
1326 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1328 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1329 = 0 is the default). The NIC is an e1000 by default on the PC
1330 target. Optionally, the MAC address can be changed to @var{mac}, the
1331 device address set to @var{addr} (PCI cards only),
1332 and a @var{name} can be assigned for use in monitor commands.
1333 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1334 that the card should have; this option currently only affects virtio cards; set
1335 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1336 NIC is created. QEMU can emulate several different models of network card.
1337 Valid values for @var{type} are
1338 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1339 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1340 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1341 Not all devices are supported on all targets. Use -net nic,model=?
1342 for a list of available devices for your target.
1344 @item -net user[,@var{option}][,@var{option}][,...]
1345 Use the user mode network stack which requires no administrator
1346 privilege to run. Valid options are:
1350 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1352 @item name=@var{name}
1353 Assign symbolic name for use in monitor commands.
1355 @item net=@var{addr}[/@var{mask}]
1356 Set IP network address the guest will see. Optionally specify the netmask,
1357 either in the form a.b.c.d or as number of valid top-most bits. Default is
1360 @item host=@var{addr}
1361 Specify the guest-visible address of the host. Default is the 2nd IP in the
1362 guest network, i.e. x.x.x.2.
1364 @item restrict=on|off
1365 If this option is enabled, the guest will be isolated, i.e. it will not be
1366 able to contact the host and no guest IP packets will be routed over the host
1367 to the outside. This option does not affect any explicitly set forwarding rules.
1369 @item hostname=@var{name}
1370 Specifies the client hostname reported by the builtin DHCP server.
1372 @item dhcpstart=@var{addr}
1373 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1374 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1376 @item dns=@var{addr}
1377 Specify the guest-visible address of the virtual nameserver. The address must
1378 be different from the host address. Default is the 3rd IP in the guest network,
1381 @item tftp=@var{dir}
1382 When using the user mode network stack, activate a built-in TFTP
1383 server. The files in @var{dir} will be exposed as the root of a TFTP server.
1384 The TFTP client on the guest must be configured in binary mode (use the command
1385 @code{bin} of the Unix TFTP client).
1387 @item bootfile=@var{file}
1388 When using the user mode network stack, broadcast @var{file} as the BOOTP
1389 filename. In conjunction with @option{tftp}, this can be used to network boot
1390 a guest from a local directory.
1392 Example (using pxelinux):
1394 qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1397 @item smb=@var{dir}[,smbserver=@var{addr}]
1398 When using the user mode network stack, activate a built-in SMB
1399 server so that Windows OSes can access to the host files in @file{@var{dir}}
1400 transparently. The IP address of the SMB server can be set to @var{addr}. By
1401 default the 4th IP in the guest network is used, i.e. x.x.x.4.
1403 In the guest Windows OS, the line:
1407 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1408 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1410 Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}.
1412 Note that a SAMBA server must be installed on the host OS.
1413 QEMU was tested successfully with smbd versions from Red Hat 9,
1414 Fedora Core 3 and OpenSUSE 11.x.
1416 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1417 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1418 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1419 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1420 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1421 be bound to a specific host interface. If no connection type is set, TCP is
1422 used. This option can be given multiple times.
1424 For example, to redirect host X11 connection from screen 1 to guest
1425 screen 0, use the following:
1429 qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1430 # this host xterm should open in the guest X11 server
1434 To redirect telnet connections from host port 5555 to telnet port on
1435 the guest, use the following:
1439 qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
1440 telnet localhost 5555
1443 Then when you use on the host @code{telnet localhost 5555}, you
1444 connect to the guest telnet server.
1446 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1447 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
1448 Forward guest TCP connections to the IP address @var{server} on port @var{port}
1449 to the character device @var{dev} or to a program executed by @var{cmd:command}
1450 which gets spawned for each connection. This option can be given multiple times.
1452 You can either use a chardev directly and have that one used throughout QEMU's
1453 lifetime, like in the following example:
1456 # open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
1457 # the guest accesses it
1458 qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...]
1461 Or you can execute a command on every TCP connection established by the guest,
1462 so that QEMU behaves similar to an inetd process for that virtual server:
1465 # call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234
1466 # and connect the TCP stream to its stdin/stdout
1467 qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
1472 Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
1473 processed and applied to -net user. Mixing them with the new configuration
1474 syntax gives undefined results. Their use for new applications is discouraged
1475 as they will be removed from future versions.
1477 @item -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1478 Connect the host TAP network interface @var{name} to VLAN @var{n}.
1480 Use the network script @var{file} to configure it and the network script
1481 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
1482 automatically provides one. The default network configure script is
1483 @file{/etc/qemu-ifup} and the default network deconfigure script is
1484 @file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
1485 to disable script execution.
1487 If running QEMU as an unprivileged user, use the network helper
1488 @var{helper} to configure the TAP interface. The default network
1489 helper executable is @file{/usr/local/libexec/qemu-bridge-helper}.
1491 @option{fd}=@var{h} can be used to specify the handle of an already
1492 opened host TAP interface.
1497 #launch a QEMU instance with the default network script
1498 qemu-system-i386 linux.img -net nic -net tap
1502 #launch a QEMU instance with two NICs, each one connected
1504 qemu-system-i386 linux.img \
1505 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
1506 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
1510 #launch a QEMU instance with the default network helper to
1511 #connect a TAP device to bridge br0
1512 qemu-system-i386 linux.img \
1513 -net nic -net tap,"helper=/usr/local/libexec/qemu-bridge-helper"
1516 @item -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
1517 Connect a host TAP network interface to a host bridge device.
1519 Use the network helper @var{helper} to configure the TAP interface and
1520 attach it to the bridge. The default network helper executable is
1521 @file{/usr/local/libexec/qemu-bridge-helper} and the default bridge
1522 device is @file{br0}.
1527 #launch a QEMU instance with the default network helper to
1528 #connect a TAP device to bridge br0
1529 qemu-system-i386 linux.img -net bridge -net nic,model=virtio
1533 #launch a QEMU instance with the default network helper to
1534 #connect a TAP device to bridge qemubr0
1535 qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
1538 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1540 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
1541 machine using a TCP socket connection. If @option{listen} is
1542 specified, QEMU waits for incoming connections on @var{port}
1543 (@var{host} is optional). @option{connect} is used to connect to
1544 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
1545 specifies an already opened TCP socket.
1549 # launch a first QEMU instance
1550 qemu-system-i386 linux.img \
1551 -net nic,macaddr=52:54:00:12:34:56 \
1552 -net socket,listen=:1234
1553 # connect the VLAN 0 of this instance to the VLAN 0
1554 # of the first instance
1555 qemu-system-i386 linux.img \
1556 -net nic,macaddr=52:54:00:12:34:57 \
1557 -net socket,connect=127.0.0.1:1234
1560 @item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1562 Create a VLAN @var{n} shared with another QEMU virtual
1563 machines using a UDP multicast socket, effectively making a bus for
1564 every QEMU with same multicast address @var{maddr} and @var{port}.
1568 Several QEMU can be running on different hosts and share same bus (assuming
1569 correct multicast setup for these hosts).
1571 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
1572 @url{http://user-mode-linux.sf.net}.
1574 Use @option{fd=h} to specify an already opened UDP multicast socket.
1579 # launch one QEMU instance
1580 qemu-system-i386 linux.img \
1581 -net nic,macaddr=52:54:00:12:34:56 \
1582 -net socket,mcast=230.0.0.1:1234
1583 # launch another QEMU instance on same "bus"
1584 qemu-system-i386 linux.img \
1585 -net nic,macaddr=52:54:00:12:34:57 \
1586 -net socket,mcast=230.0.0.1:1234
1587 # launch yet another QEMU instance on same "bus"
1588 qemu-system-i386 linux.img \
1589 -net nic,macaddr=52:54:00:12:34:58 \
1590 -net socket,mcast=230.0.0.1:1234
1593 Example (User Mode Linux compat.):
1595 # launch QEMU instance (note mcast address selected
1597 qemu-system-i386 linux.img \
1598 -net nic,macaddr=52:54:00:12:34:56 \
1599 -net socket,mcast=239.192.168.1:1102
1601 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
1604 Example (send packets from host's 1.2.3.4):
1606 qemu-system-i386 linux.img \
1607 -net nic,macaddr=52:54:00:12:34:56 \
1608 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
1611 @item -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
1612 Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
1613 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
1614 and MODE @var{octalmode} to change default ownership and permissions for
1615 communication port. This option is only available if QEMU has been compiled
1616 with vde support enabled.
1621 vde_switch -F -sock /tmp/myswitch
1622 # launch QEMU instance
1623 qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch
1626 @item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
1627 Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
1628 At most @var{len} bytes (64k by default) per packet are stored. The file format is
1629 libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
1632 Indicate that no network devices should be configured. It is used to
1633 override the default configuration (@option{-net nic -net user}) which
1634 is activated if no @option{-net} options are provided.
1641 DEFHEADING(Character device options:)
1643 DEF("chardev", HAS_ARG, QEMU_OPTION_chardev,
1644 "-chardev null,id=id[,mux=on|off]\n"
1645 "-chardev socket,id=id[,host=host],port=host[,to=to][,ipv4][,ipv6][,nodelay]\n"
1646 " [,server][,nowait][,telnet][,mux=on|off] (tcp)\n"
1647 "-chardev socket,id=id,path=path[,server][,nowait][,telnet],[mux=on|off] (unix)\n"
1648 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n"
1649 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n"
1650 "-chardev msmouse,id=id[,mux=on|off]\n"
1651 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n"
1653 "-chardev file,id=id,path=path[,mux=on|off]\n"
1654 "-chardev pipe,id=id,path=path[,mux=on|off]\n"
1656 "-chardev console,id=id[,mux=on|off]\n"
1657 "-chardev serial,id=id,path=path[,mux=on|off]\n"
1659 "-chardev pty,id=id[,mux=on|off]\n"
1660 "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n"
1662 #ifdef CONFIG_BRLAPI
1663 "-chardev braille,id=id[,mux=on|off]\n"
1665 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
1666 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
1667 "-chardev tty,id=id,path=path[,mux=on|off]\n"
1669 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
1670 "-chardev parport,id=id,path=path[,mux=on|off]\n"
1672 #if defined(CONFIG_SPICE)
1673 "-chardev spicevmc,id=id,name=name[,debug=debug]\n"
1680 The general form of a character device option is:
1683 @item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
1701 The specific backend will determine the applicable options.
1703 All devices must have an id, which can be any string up to 127 characters long.
1704 It is used to uniquely identify this device in other command line directives.
1706 A character device may be used in multiplexing mode by multiple front-ends.
1707 The key sequence of @key{Control-a} and @key{c} will rotate the input focus
1708 between attached front-ends. Specify @option{mux=on} to enable this mode.
1710 Options to each backend are described below.
1712 @item -chardev null ,id=@var{id}
1713 A void device. This device will not emit any data, and will drop any data it
1714 receives. The null backend does not take any options.
1716 @item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet]
1718 Create a two-way stream socket, which can be either a TCP or a unix socket. A
1719 unix socket will be created if @option{path} is specified. Behaviour is
1720 undefined if TCP options are specified for a unix socket.
1722 @option{server} specifies that the socket shall be a listening socket.
1724 @option{nowait} specifies that QEMU should not block waiting for a client to
1725 connect to a listening socket.
1727 @option{telnet} specifies that traffic on the socket should interpret telnet
1730 TCP and unix socket options are given below:
1734 @item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
1736 @option{host} for a listening socket specifies the local address to be bound.
1737 For a connecting socket species the remote host to connect to. @option{host} is
1738 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
1740 @option{port} for a listening socket specifies the local port to be bound. For a
1741 connecting socket specifies the port on the remote host to connect to.
1742 @option{port} can be given as either a port number or a service name.
1743 @option{port} is required.
1745 @option{to} is only relevant to listening sockets. If it is specified, and
1746 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
1747 to and including @option{to} until it succeeds. @option{to} must be specified
1750 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1751 If neither is specified the socket may use either protocol.
1753 @option{nodelay} disables the Nagle algorithm.
1755 @item unix options: path=@var{path}
1757 @option{path} specifies the local path of the unix socket. @option{path} is
1762 @item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
1764 Sends all traffic from the guest to a remote host over UDP.
1766 @option{host} specifies the remote host to connect to. If not specified it
1767 defaults to @code{localhost}.
1769 @option{port} specifies the port on the remote host to connect to. @option{port}
1772 @option{localaddr} specifies the local address to bind to. If not specified it
1773 defaults to @code{0.0.0.0}.
1775 @option{localport} specifies the local port to bind to. If not specified any
1776 available local port will be used.
1778 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
1779 If neither is specified the device may use either protocol.
1781 @item -chardev msmouse ,id=@var{id}
1783 Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
1786 @item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
1788 Connect to a QEMU text console. @option{vc} may optionally be given a specific
1791 @option{width} and @option{height} specify the width and height respectively of
1792 the console, in pixels.
1794 @option{cols} and @option{rows} specify that the console be sized to fit a text
1795 console with the given dimensions.
1797 @item -chardev file ,id=@var{id} ,path=@var{path}
1799 Log all traffic received from the guest to a file.
1801 @option{path} specifies the path of the file to be opened. This file will be
1802 created if it does not already exist, and overwritten if it does. @option{path}
1805 @item -chardev pipe ,id=@var{id} ,path=@var{path}
1807 Create a two-way connection to the guest. The behaviour differs slightly between
1808 Windows hosts and other hosts:
1810 On Windows, a single duplex pipe will be created at
1811 @file{\\.pipe\@option{path}}.
1813 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
1814 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
1815 received by the guest. Data written by the guest can be read from
1816 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
1819 @option{path} forms part of the pipe path as described above. @option{path} is
1822 @item -chardev console ,id=@var{id}
1824 Send traffic from the guest to QEMU's standard output. @option{console} does not
1827 @option{console} is only available on Windows hosts.
1829 @item -chardev serial ,id=@var{id} ,path=@option{path}
1831 Send traffic from the guest to a serial device on the host.
1834 only available on Windows hosts.
1836 @option{path} specifies the name of the serial device to open.
1838 @item -chardev pty ,id=@var{id}
1840 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
1841 not take any options.
1843 @option{pty} is not available on Windows hosts.
1845 @item -chardev stdio ,id=@var{id} [,signal=on|off]
1846 Connect to standard input and standard output of the QEMU process.
1848 @option{signal} controls if signals are enabled on the terminal, that includes
1849 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
1850 default, use @option{signal=off} to disable it.
1852 @option{stdio} is not available on Windows hosts.
1854 @item -chardev braille ,id=@var{id}
1856 Connect to a local BrlAPI server. @option{braille} does not take any options.
1858 @item -chardev tty ,id=@var{id} ,path=@var{path}
1860 Connect to a local tty device.
1862 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
1865 @option{path} specifies the path to the tty. @option{path} is required.
1867 @item -chardev parport ,id=@var{id} ,path=@var{path}
1869 @option{parport} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
1871 Connect to a local parallel port.
1873 @option{path} specifies the path to the parallel port device. @option{path} is
1876 @item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
1878 @option{spicevmc} is only available when spice support is built in.
1880 @option{debug} debug level for spicevmc
1882 @option{name} name of spice channel to connect to
1884 Connect to a spice virtual machine channel, such as vdiport.
1892 DEFHEADING(Device URL Syntax:)
1894 In addition to using normal file images for the emulated storage devices,
1895 QEMU can also use networked resources such as iSCSI devices. These are
1896 specified using a special URL syntax.
1900 iSCSI support allows QEMU to access iSCSI resources directly and use as
1901 images for the guest storage. Both disk and cdrom images are supported.
1903 Syntax for specifying iSCSI LUNs is
1904 ``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
1906 By default qemu will use the iSCSI initiator-name
1907 'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command
1908 line or a configuration file.
1911 Example (without authentication):
1913 qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
1914 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
1915 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
1918 Example (CHAP username/password via URL):
1920 qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
1923 Example (CHAP username/password via environment variables):
1925 LIBISCSI_CHAP_USERNAME="user" \
1926 LIBISCSI_CHAP_PASSWORD="password" \
1927 qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
1930 iSCSI support is an optional feature of QEMU and only available when
1931 compiled and linked against libiscsi.
1933 DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi,
1934 "-iscsi [user=user][,password=password]\n"
1935 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n"
1936 " [,initiator-name=iqn]\n"
1937 " iSCSI session parameters\n", QEMU_ARCH_ALL)
1940 iSCSI parameters such as username and password can also be specified via
1941 a configuration file. See qemu-doc for more information and examples.
1944 QEMU supports NBD (Network Block Devices) both using TCP protocol as well
1945 as Unix Domain Sockets.
1947 Syntax for specifying a NBD device using TCP
1948 ``nbd:<server-ip>:<port>[:exportname=<export>]''
1950 Syntax for specifying a NBD device using Unix Domain Sockets
1951 ``nbd:unix:<domain-socket>[:exportname=<export>]''
1956 qemu-system-i386 --drive file=nbd:192.0.2.1:30000
1959 Example for Unix Domain Sockets
1961 qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket
1965 Sheepdog is a distributed storage system for QEMU.
1966 QEMU supports using either local sheepdog devices or remote networked
1969 Syntax for specifying a sheepdog device
1971 ``sheepdog:<vdiname>''
1973 ``sheepdog:<vdiname>:<snapid>''
1975 ``sheepdog:<vdiname>:<tag>''
1977 ``sheepdog:<host>:<port>:<vdiname>''
1979 ``sheepdog:<host>:<port>:<vdiname>:<snapid>''
1981 ``sheepdog:<host>:<port>:<vdiname>:<tag>''
1986 qemu-system-i386 --drive file=sheepdog:192.0.2.1:30000:MyVirtualMachine
1989 See also @url{http://http://www.osrg.net/sheepdog/}.
1994 DEFHEADING(Bluetooth(R) options:)
1996 DEF("bt", HAS_ARG, QEMU_OPTION_bt, \
1997 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \
1998 "-bt hci,host[:id]\n" \
1999 " use host's HCI with the given name\n" \
2000 "-bt hci[,vlan=n]\n" \
2001 " emulate a standard HCI in virtual scatternet 'n'\n" \
2002 "-bt vhci[,vlan=n]\n" \
2003 " add host computer to virtual scatternet 'n' using VHCI\n" \
2004 "-bt device:dev[,vlan=n]\n" \
2005 " emulate a bluetooth device 'dev' in scatternet 'n'\n",
2012 Defines the function of the corresponding Bluetooth HCI. -bt options
2013 are matched with the HCIs present in the chosen machine type. For
2014 example when emulating a machine with only one HCI built into it, only
2015 the first @code{-bt hci[...]} option is valid and defines the HCI's
2016 logic. The Transport Layer is decided by the machine type. Currently
2017 the machines @code{n800} and @code{n810} have one HCI and all other
2021 The following three types are recognized:
2025 (default) The corresponding Bluetooth HCI assumes no internal logic
2026 and will not respond to any HCI commands or emit events.
2028 @item -bt hci,host[:@var{id}]
2029 (@code{bluez} only) The corresponding HCI passes commands / events
2030 to / from the physical HCI identified by the name @var{id} (default:
2031 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
2032 capable systems like Linux.
2034 @item -bt hci[,vlan=@var{n}]
2035 Add a virtual, standard HCI that will participate in the Bluetooth
2036 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
2037 VLANs, devices inside a bluetooth network @var{n} can only communicate
2038 with other devices in the same network (scatternet).
2041 @item -bt vhci[,vlan=@var{n}]
2042 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2043 to the host bluetooth stack instead of to the emulated target. This
2044 allows the host and target machines to participate in a common scatternet
2045 and communicate. Requires the Linux @code{vhci} driver installed. Can
2046 be used as following:
2049 qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2052 @item -bt device:@var{dev}[,vlan=@var{n}]
2053 Emulate a bluetooth device @var{dev} and place it in network @var{n}
2054 (default @code{0}). QEMU can only emulate one type of bluetooth devices
2059 Virtual wireless keyboard implementing the HIDP bluetooth profile.
2066 DEFHEADING(Linux/Multiboot boot specific:)
2069 When using these options, you can use a given Linux or Multiboot
2070 kernel without installing it in the disk image. It can be useful
2071 for easier testing of various kernels.
2076 DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \
2077 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL)
2079 @item -kernel @var{bzImage}
2081 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2082 or in multiboot format.
2085 DEF("append", HAS_ARG, QEMU_OPTION_append, \
2086 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL)
2088 @item -append @var{cmdline}
2090 Use @var{cmdline} as kernel command line
2093 DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \
2094 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL)
2096 @item -initrd @var{file}
2098 Use @var{file} as initial ram disk.
2100 @item -initrd "@var{file1} arg=foo,@var{file2}"
2102 This syntax is only available with multiboot.
2104 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
2108 DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \
2109 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL)
2111 @item -dtb @var{file}
2113 Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
2123 DEFHEADING(Debug/Expert options:)
2129 DEF("serial", HAS_ARG, QEMU_OPTION_serial, \
2130 "-serial dev redirect the serial port to char device 'dev'\n",
2133 @item -serial @var{dev}
2135 Redirect the virtual serial port to host character device
2136 @var{dev}. The default device is @code{vc} in graphical mode and
2137 @code{stdio} in non graphical mode.
2139 This option can be used several times to simulate up to 4 serial
2142 Use @code{-serial none} to disable all serial ports.
2144 Available character devices are:
2146 @item vc[:@var{W}x@var{H}]
2147 Virtual console. Optionally, a width and height can be given in pixel with
2151 It is also possible to specify width or height in characters:
2156 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
2158 No device is allocated.
2162 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
2163 parameters are set according to the emulated ones.
2164 @item /dev/parport@var{N}
2165 [Linux only, parallel port only] Use host parallel port
2166 @var{N}. Currently SPP and EPP parallel port features can be used.
2167 @item file:@var{filename}
2168 Write output to @var{filename}. No character can be read.
2170 [Unix only] standard input/output
2171 @item pipe:@var{filename}
2172 name pipe @var{filename}
2174 [Windows only] Use host serial port @var{n}
2175 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
2176 This implements UDP Net Console.
2177 When @var{remote_host} or @var{src_ip} are not specified
2178 they default to @code{0.0.0.0}.
2179 When not using a specified @var{src_port} a random port is automatically chosen.
2181 If you just want a simple readonly console you can use @code{netcat} or
2182 @code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
2183 @code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
2184 will appear in the netconsole session.
2186 If you plan to send characters back via netconsole or you want to stop
2187 and start QEMU a lot of times, you should have QEMU use the same
2188 source port each time by using something like @code{-serial
2189 udp::4555@@:4556} to QEMU. Another approach is to use a patched
2190 version of netcat which can listen to a TCP port and send and receive
2191 characters via udp. If you have a patched version of netcat which
2192 activates telnet remote echo and single char transfer, then you can
2193 use the following options to step up a netcat redirector to allow
2194 telnet on port 5555 to access the QEMU port.
2197 -serial udp::4555@@:4556
2198 @item netcat options:
2199 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
2200 @item telnet options:
2204 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay]
2205 The TCP Net Console has two modes of operation. It can send the serial
2206 I/O to a location or wait for a connection from a location. By default
2207 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
2208 the @var{server} option QEMU will wait for a client socket application
2209 to connect to the port before continuing, unless the @code{nowait}
2210 option was specified. The @code{nodelay} option disables the Nagle buffering
2211 algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only
2212 one TCP connection at a time is accepted. You can use @code{telnet} to
2213 connect to the corresponding character device.
2215 @item Example to send tcp console to 192.168.0.2 port 4444
2216 -serial tcp:192.168.0.2:4444
2217 @item Example to listen and wait on port 4444 for connection
2218 -serial tcp::4444,server
2219 @item Example to not wait and listen on ip 192.168.0.100 port 4444
2220 -serial tcp:192.168.0.100:4444,server,nowait
2223 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
2224 The telnet protocol is used instead of raw tcp sockets. The options
2225 work the same as if you had specified @code{-serial tcp}. The
2226 difference is that the port acts like a telnet server or client using
2227 telnet option negotiation. This will also allow you to send the
2228 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
2229 sequence. Typically in unix telnet you do it with Control-] and then
2230 type "send break" followed by pressing the enter key.
2232 @item unix:@var{path}[,server][,nowait]
2233 A unix domain socket is used instead of a tcp socket. The option works the
2234 same as if you had specified @code{-serial tcp} except the unix domain socket
2235 @var{path} is used for connections.
2237 @item mon:@var{dev_string}
2238 This is a special option to allow the monitor to be multiplexed onto
2239 another serial port. The monitor is accessed with key sequence of
2240 @key{Control-a} and then pressing @key{c}. See monitor access
2241 @ref{pcsys_keys} in the -nographic section for more keys.
2242 @var{dev_string} should be any one of the serial devices specified
2243 above. An example to multiplex the monitor onto a telnet server
2244 listening on port 4444 would be:
2246 @item -serial mon:telnet::4444,server,nowait
2250 Braille device. This will use BrlAPI to display the braille output on a real
2254 Three button serial mouse. Configure the guest to use Microsoft protocol.
2258 DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \
2259 "-parallel dev redirect the parallel port to char device 'dev'\n",
2262 @item -parallel @var{dev}
2264 Redirect the virtual parallel port to host device @var{dev} (same
2265 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
2266 be used to use hardware devices connected on the corresponding host
2269 This option can be used several times to simulate up to 3 parallel
2272 Use @code{-parallel none} to disable all parallel ports.
2275 DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \
2276 "-monitor dev redirect the monitor to char device 'dev'\n",
2279 @item -monitor @var{dev}
2281 Redirect the monitor to host device @var{dev} (same devices as the
2283 The default device is @code{vc} in graphical mode and @code{stdio} in
2286 DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \
2287 "-qmp dev like -monitor but opens in 'control' mode\n",
2290 @item -qmp @var{dev}
2292 Like -monitor but opens in 'control' mode.
2295 DEF("mon", HAS_ARG, QEMU_OPTION_mon, \
2296 "-mon chardev=[name][,mode=readline|control][,default]\n", QEMU_ARCH_ALL)
2298 @item -mon chardev=[name][,mode=readline|control][,default]
2300 Setup monitor on chardev @var{name}.
2303 DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \
2304 "-debugcon dev redirect the debug console to char device 'dev'\n",
2307 @item -debugcon @var{dev}
2309 Redirect the debug console to host device @var{dev} (same devices as the
2310 serial port). The debug console is an I/O port which is typically port
2311 0xe9; writing to that I/O port sends output to this device.
2312 The default device is @code{vc} in graphical mode and @code{stdio} in
2316 DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \
2317 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL)
2319 @item -pidfile @var{file}
2321 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
2325 DEF("singlestep", 0, QEMU_OPTION_singlestep, \
2326 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL)
2330 Run the emulation in single step mode.
2333 DEF("S", 0, QEMU_OPTION_S, \
2334 "-S freeze CPU at startup (use 'c' to start execution)\n",
2339 Do not start CPU at startup (you must type 'c' in the monitor).
2342 DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \
2343 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL)
2345 @item -gdb @var{dev}
2347 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
2348 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
2349 stdio are reasonable use case. The latter is allowing to start QEMU from
2350 within gdb and establish the connection via a pipe:
2352 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
2356 DEF("s", 0, QEMU_OPTION_s, \
2357 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n",
2362 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
2363 (@pxref{gdb_usage}).
2366 DEF("d", HAS_ARG, QEMU_OPTION_d, \
2367 "-d item1,... output log to /tmp/qemu.log (use -d ? for a list of log items)\n",
2372 Output log in /tmp/qemu.log
2375 DEF("D", HAS_ARG, QEMU_OPTION_D, \
2376 "-D logfile output log to logfile (instead of the default /tmp/qemu.log)\n",
2379 @item -D @var{logfile}
2381 Output log in @var{logfile} instead of /tmp/qemu.log
2384 DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \
2385 "-hdachs c,h,s[,t]\n" \
2386 " force hard disk 0 physical geometry and the optional BIOS\n" \
2387 " translation (t=none or lba) (usually QEMU can guess them)\n",
2390 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
2392 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
2393 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
2394 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
2395 all those parameters. This option is useful for old MS-DOS disk
2399 DEF("L", HAS_ARG, QEMU_OPTION_L, \
2400 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n",
2405 Set the directory for the BIOS, VGA BIOS and keymaps.
2408 DEF("bios", HAS_ARG, QEMU_OPTION_bios, \
2409 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL)
2411 @item -bios @var{file}
2413 Set the filename for the BIOS.
2416 DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \
2417 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL)
2421 Enable KVM full virtualization support. This option is only available
2422 if KVM support is enabled when compiling.
2425 DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid,
2426 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL)
2427 DEF("xen-create", 0, QEMU_OPTION_xen_create,
2428 "-xen-create create domain using xen hypercalls, bypassing xend\n"
2429 " warning: should not be used when xend is in use\n",
2431 DEF("xen-attach", 0, QEMU_OPTION_xen_attach,
2432 "-xen-attach attach to existing xen domain\n"
2433 " xend will use this when starting QEMU\n",
2436 @item -xen-domid @var{id}
2438 Specify xen guest domain @var{id} (XEN only).
2441 Create domain using xen hypercalls, bypassing xend.
2442 Warning: should not be used when xend is in use (XEN only).
2445 Attach to existing xen domain.
2446 xend will use this when starting QEMU (XEN only).
2449 DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \
2450 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL)
2454 Exit instead of rebooting.
2457 DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \
2458 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL)
2461 @findex -no-shutdown
2462 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
2463 This allows for instance switching to monitor to commit changes to the
2467 DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \
2468 "-loadvm [tag|id]\n" \
2469 " start right away with a saved state (loadvm in monitor)\n",
2472 @item -loadvm @var{file}
2474 Start right away with a saved state (@code{loadvm} in monitor)
2478 DEF("daemonize", 0, QEMU_OPTION_daemonize, \
2479 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL)
2484 Daemonize the QEMU process after initialization. QEMU will not detach from
2485 standard IO until it is ready to receive connections on any of its devices.
2486 This option is a useful way for external programs to launch QEMU without having
2487 to cope with initialization race conditions.
2490 DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \
2491 "-option-rom rom load a file, rom, into the option ROM space\n",
2494 @item -option-rom @var{file}
2496 Load the contents of @var{file} as an option ROM.
2497 This option is useful to load things like EtherBoot.
2500 DEF("clock", HAS_ARG, QEMU_OPTION_clock, \
2501 "-clock force the use of the given methods for timer alarm.\n" \
2502 " To see what timers are available use -clock ?\n",
2505 @item -clock @var{method}
2507 Force the use of the given methods for timer alarm. To see what timers
2508 are available use -clock ?.
2511 HXCOMM Options deprecated by -rtc
2512 DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL)
2513 DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL)
2515 DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \
2516 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \
2517 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n",
2522 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
2524 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
2525 UTC or local time, respectively. @code{localtime} is required for correct date in
2526 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
2527 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
2529 By default the RTC is driven by the host system time. This allows to use the
2530 RTC as accurate reference clock inside the guest, specifically if the host
2531 time is smoothly following an accurate external reference clock, e.g. via NTP.
2532 If you want to isolate the guest time from the host, you can set @option{clock}
2533 to @code{rt} instead. To even prevent it from progressing during suspension,
2534 you can set it to @code{vm}.
2536 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
2537 specifically with Windows' ACPI HAL. This option will try to figure out how
2538 many timer interrupts were not processed by the Windows guest and will
2542 DEF("icount", HAS_ARG, QEMU_OPTION_icount, \
2543 "-icount [N|auto]\n" \
2544 " enable virtual instruction counter with 2^N clock ticks per\n" \
2545 " instruction\n", QEMU_ARCH_ALL)
2547 @item -icount [@var{N}|auto]
2549 Enable virtual instruction counter. The virtual cpu will execute one
2550 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
2551 then the virtual cpu speed will be automatically adjusted to keep virtual
2552 time within a few seconds of real time.
2554 Note that while this option can give deterministic behavior, it does not
2555 provide cycle accurate emulation. Modern CPUs contain superscalar out of
2556 order cores with complex cache hierarchies. The number of instructions
2557 executed often has little or no correlation with actual performance.
2560 DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \
2561 "-watchdog i6300esb|ib700\n" \
2562 " enable virtual hardware watchdog [default=none]\n",
2565 @item -watchdog @var{model}
2567 Create a virtual hardware watchdog device. Once enabled (by a guest
2568 action), the watchdog must be periodically polled by an agent inside
2569 the guest or else the guest will be restarted.
2571 The @var{model} is the model of hardware watchdog to emulate. Choices
2572 for model are: @code{ib700} (iBASE 700) which is a very simple ISA
2573 watchdog with a single timer, or @code{i6300esb} (Intel 6300ESB I/O
2574 controller hub) which is a much more featureful PCI-based dual-timer
2575 watchdog. Choose a model for which your guest has drivers.
2577 Use @code{-watchdog ?} to list available hardware models. Only one
2578 watchdog can be enabled for a guest.
2581 DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \
2582 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \
2583 " action when watchdog fires [default=reset]\n",
2586 @item -watchdog-action @var{action}
2588 The @var{action} controls what QEMU will do when the watchdog timer
2591 @code{reset} (forcefully reset the guest).
2592 Other possible actions are:
2593 @code{shutdown} (attempt to gracefully shutdown the guest),
2594 @code{poweroff} (forcefully poweroff the guest),
2595 @code{pause} (pause the guest),
2596 @code{debug} (print a debug message and continue), or
2597 @code{none} (do nothing).
2599 Note that the @code{shutdown} action requires that the guest responds
2600 to ACPI signals, which it may not be able to do in the sort of
2601 situations where the watchdog would have expired, and thus
2602 @code{-watchdog-action shutdown} is not recommended for production use.
2607 @item -watchdog i6300esb -watchdog-action pause
2608 @item -watchdog ib700
2612 DEF("echr", HAS_ARG, QEMU_OPTION_echr, \
2613 "-echr chr set terminal escape character instead of ctrl-a\n",
2617 @item -echr @var{numeric_ascii_value}
2619 Change the escape character used for switching to the monitor when using
2620 monitor and serial sharing. The default is @code{0x01} when using the
2621 @code{-nographic} option. @code{0x01} is equal to pressing
2622 @code{Control-a}. You can select a different character from the ascii
2623 control keys where 1 through 26 map to Control-a through Control-z. For
2624 instance you could use the either of the following to change the escape
2625 character to Control-t.
2632 DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \
2633 "-virtioconsole c\n" \
2634 " set virtio console\n", QEMU_ARCH_ALL)
2636 @item -virtioconsole @var{c}
2637 @findex -virtioconsole
2640 This option is maintained for backward compatibility.
2642 Please use @code{-device virtconsole} for the new way of invocation.
2645 DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \
2646 "-show-cursor show cursor\n", QEMU_ARCH_ALL)
2649 @findex -show-cursor
2653 DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \
2654 "-tb-size n set TB size\n", QEMU_ARCH_ALL)
2656 @item -tb-size @var{n}
2661 DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \
2662 "-incoming p prepare for incoming migration, listen on port p\n",
2665 @item -incoming @var{port}
2667 Prepare for incoming migration, listen on @var{port}.
2670 DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \
2671 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL)
2675 Don't create default devices. Normally, QEMU sets the default devices like serial
2676 port, parallel port, virtual console, monitor device, VGA adapter, floppy and
2677 CD-ROM drive and others. The @code{-nodefaults} option will disable all those
2682 DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \
2683 "-chroot dir chroot to dir just before starting the VM\n",
2687 @item -chroot @var{dir}
2689 Immediately before starting guest execution, chroot to the specified
2690 directory. Especially useful in combination with -runas.
2694 DEF("runas", HAS_ARG, QEMU_OPTION_runas, \
2695 "-runas user change to user id user just before starting the VM\n",
2699 @item -runas @var{user}
2701 Immediately before starting guest execution, drop root privileges, switching
2702 to the specified user.
2705 DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env,
2706 "-prom-env variable=value\n"
2707 " set OpenBIOS nvram variables\n",
2708 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
2710 @item -prom-env @var{variable}=@var{value}
2712 Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only).
2714 DEF("semihosting", 0, QEMU_OPTION_semihosting,
2715 "-semihosting semihosting mode\n", QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA)
2718 @findex -semihosting
2719 Semihosting mode (ARM, M68K, Xtensa only).
2721 DEF("old-param", 0, QEMU_OPTION_old_param,
2722 "-old-param old param mode\n", QEMU_ARCH_ARM)
2725 @findex -old-param (ARM)
2726 Old param mode (ARM only).
2729 DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \
2730 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n",
2735 Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will
2736 disable it. The default is 'off'.
2739 DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig,
2740 "-readconfig <file>\n", QEMU_ARCH_ALL)
2742 @item -readconfig @var{file}
2744 Read device configuration from @var{file}. This approach is useful when you want to spawn
2745 QEMU process with many command line options but you don't want to exceed the command line
2748 DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
2749 "-writeconfig <file>\n"
2750 " read/write config file\n", QEMU_ARCH_ALL)
2752 @item -writeconfig @var{file}
2753 @findex -writeconfig
2754 Write device configuration to @var{file}. The @var{file} can be either filename to save
2755 command line and device configuration into file or dash @code{-}) character to print the
2756 output to stdout. This can be later used as input file for @code{-readconfig} option.
2758 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig,
2760 " do not load default config files at startup\n",
2764 @findex -nodefconfig
2765 Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
2766 The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
2768 DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
2770 " do not load user-provided config files at startup\n",
2773 @item -no-user-config
2774 @findex -no-user-config
2775 The @code{-no-user-config} option makes QEMU not load any of the user-provided
2776 config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config
2777 files from @var{datadir}.
2779 DEF("trace", HAS_ARG, QEMU_OPTION_trace,
2780 "-trace [events=<file>][,file=<file>]\n"
2781 " specify tracing options\n",
2784 HXCOMM This line is not accurate, as some sub-options are backend-specific but
2785 HXCOMM HX does not support conditional compilation of text.
2786 @item -trace [events=@var{file}][,file=@var{file}]
2789 Specify tracing options.
2792 @item events=@var{file}
2793 Immediately enable events listed in @var{file}.
2794 The file must contain one event name (as listed in the @var{trace-events} file)
2796 This option is only available if QEMU has been compiled with
2797 either @var{simple} or @var{stderr} tracing backend.
2798 @item file=@var{file}
2799 Log output traces to @var{file}.
2801 This option is only available if QEMU has been compiled with
2802 the @var{simple} tracing backend.
2806 DEF("qtest", HAS_ARG, QEMU_OPTION_qtest,
2807 "-qtest CHR specify tracing options\n",
2810 DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log,
2811 "-qtest-log LOG specify tracing options\n",
2815 DEF("enable-fips", 0, QEMU_OPTION_enablefips,
2816 "-enable-fips enable FIPS 140-2 compliance\n",
2821 @findex -enable-fips
2822 Enable FIPS 140-2 compliance mode.
2825 HXCOMM This is the last statement. Insert new options before this line!