1HXCOMM Use DEFHEADING() to define headings in both help text and texi 2HXCOMM Text between STEXI and ETEXI are copied to texi version and 3HXCOMM discarded from C version 4HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to 5HXCOMM construct option structures, enums and help message for specified 6HXCOMM architectures. 7HXCOMM HXCOMM can be used for comments, discarded from both texi and C 8 9DEFHEADING(Standard options:) 10STEXI 11@table @option 12ETEXI 13 14DEF("help", 0, QEMU_OPTION_h, 15 "-h or -help display this help and exit\n", QEMU_ARCH_ALL) 16STEXI 17@item -h 18@findex -h 19Display help and exit 20ETEXI 21 22DEF("version", 0, QEMU_OPTION_version, 23 "-version display version information and exit\n", QEMU_ARCH_ALL) 24STEXI 25@item -version 26@findex -version 27Display version information and exit 28ETEXI 29 30DEF("machine", HAS_ARG, QEMU_OPTION_machine, \ 31 "-machine [type=]name[,prop[=value][,...]]\n" 32 " selects emulated machine ('-machine help' for list)\n" 33 " property accel=accel1[:accel2[:...]] selects accelerator\n" 34 " supported accelerators are kvm, xen, tcg (default: tcg)\n" 35 " kernel_irqchip=on|off controls accelerated irqchip support\n" 36 " vmport=on|off controls emulation of vmport (default: on)\n" 37 " kvm_shadow_mem=size of KVM shadow MMU\n" 38 " dump-guest-core=on|off include guest memory in a core dump (default=on)\n" 39 " mem-merge=on|off controls memory merge support (default: on)\n" 40 " iommu=on|off controls emulated Intel IOMMU (VT-d) support (default=off)\n", 41 QEMU_ARCH_ALL) 42STEXI 43@item -machine [type=]@var{name}[,prop=@var{value}[,...]] 44@findex -machine 45Select the emulated machine by @var{name}. Use @code{-machine help} to list 46available machines. Supported machine properties are: 47@table @option 48@item accel=@var{accels1}[:@var{accels2}[:...]] 49This is used to enable an accelerator. Depending on the target architecture, 50kvm, xen, or tcg can be available. By default, tcg is used. If there is more 51than one accelerator specified, the next one is used if the previous one fails 52to initialize. 53@item kernel_irqchip=on|off 54Enables in-kernel irqchip support for the chosen accelerator when available. 55@item vmport=on|off 56Enables emulation of VMWare IO port, for vmmouse etc. (enabled by default) 57@item kvm_shadow_mem=size 58Defines the size of the KVM shadow MMU. 59@item dump-guest-core=on|off 60Include guest memory in a core dump. The default is on. 61@item mem-merge=on|off 62Enables or disables memory merge support. This feature, when supported by 63the host, de-duplicates identical memory pages among VMs instances 64(enabled by default). 65@item iommu=on|off 66Enables or disables emulated Intel IOMMU (VT-d) support. The default is off. 67@end table 68ETEXI 69 70HXCOMM Deprecated by -machine 71DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL) 72 73DEF("cpu", HAS_ARG, QEMU_OPTION_cpu, 74 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL) 75STEXI 76@item -cpu @var{model} 77@findex -cpu 78Select CPU model (@code{-cpu help} for list and additional feature selection) 79ETEXI 80 81DEF("smp", HAS_ARG, QEMU_OPTION_smp, 82 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n" 83 " set the number of CPUs to 'n' [default=1]\n" 84 " maxcpus= maximum number of total cpus, including\n" 85 " offline CPUs for hotplug, etc\n" 86 " cores= number of CPU cores on one socket\n" 87 " threads= number of threads on one CPU core\n" 88 " sockets= number of discrete sockets in the system\n", 89 QEMU_ARCH_ALL) 90STEXI 91@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}] 92@findex -smp 93Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255 94CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs 95to 4. 96For the PC target, the number of @var{cores} per socket, the number 97of @var{threads} per cores and the total number of @var{sockets} can be 98specified. Missing values will be computed. If any on the three values is 99given, the total number of CPUs @var{n} can be omitted. @var{maxcpus} 100specifies the maximum number of hotpluggable CPUs. 101ETEXI 102 103DEF("numa", HAS_ARG, QEMU_OPTION_numa, 104 "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n" 105 "-numa node[,memdev=id][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL) 106STEXI 107@item -numa node[,mem=@var{size}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}] 108@item -numa node[,memdev=@var{id}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}] 109@findex -numa 110Simulate a multi node NUMA system. If @samp{mem}, @samp{memdev} 111and @samp{cpus} are omitted, resources are split equally. Also, note 112that the -@option{numa} option doesn't allocate any of the specified 113resources. That is, it just assigns existing resources to NUMA nodes. This 114means that one still has to use the @option{-m}, @option{-smp} options 115to allocate RAM and VCPUs respectively, and possibly @option{-object} 116to specify the memory backend for the @samp{memdev} suboption. 117 118@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, if one 119node uses @samp{memdev}, all of them have to use it. 120ETEXI 121 122DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd, 123 "-add-fd fd=fd,set=set[,opaque=opaque]\n" 124 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL) 125STEXI 126@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}] 127@findex -add-fd 128 129Add a file descriptor to an fd set. Valid options are: 130 131@table @option 132@item fd=@var{fd} 133This option defines the file descriptor of which a duplicate is added to fd set. 134The file descriptor cannot be stdin, stdout, or stderr. 135@item set=@var{set} 136This option defines the ID of the fd set to add the file descriptor to. 137@item opaque=@var{opaque} 138This option defines a free-form string that can be used to describe @var{fd}. 139@end table 140 141You can open an image using pre-opened file descriptors from an fd set: 142@example 143qemu-system-i386 144-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 145-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 146-drive file=/dev/fdset/2,index=0,media=disk 147@end example 148ETEXI 149 150DEF("set", HAS_ARG, QEMU_OPTION_set, 151 "-set group.id.arg=value\n" 152 " set <arg> parameter for item <id> of type <group>\n" 153 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL) 154STEXI 155@item -set @var{group}.@var{id}.@var{arg}=@var{value} 156@findex -set 157Set parameter @var{arg} for item @var{id} of type @var{group}\n" 158ETEXI 159 160DEF("global", HAS_ARG, QEMU_OPTION_global, 161 "-global driver.prop=value\n" 162 " set a global default for a driver property\n", 163 QEMU_ARCH_ALL) 164STEXI 165@item -global @var{driver}.@var{prop}=@var{value} 166@findex -global 167Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.: 168 169@example 170qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk 171@end example 172 173In particular, you can use this to set driver properties for devices which are 174created automatically by the machine model. To create a device which is not 175created automatically and set properties on it, use -@option{device}. 176ETEXI 177 178DEF("boot", HAS_ARG, QEMU_OPTION_boot, 179 "-boot [order=drives][,once=drives][,menu=on|off]\n" 180 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n" 181 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n" 182 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n" 183 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n" 184 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n", 185 QEMU_ARCH_ALL) 186STEXI 187@item -boot [order=@var{drives}][,once=@var{drives}][,menu=on|off][,splash=@var{sp_name}][,splash-time=@var{sp_time}][,reboot-timeout=@var{rb_timeout}][,strict=on|off] 188@findex -boot 189Specify boot order @var{drives} as a string of drive letters. Valid 190drive letters depend on the target achitecture. The x86 PC uses: a, b 191(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot 192from network adapter 1-4), hard disk boot is the default. To apply a 193particular boot order only on the first startup, specify it via 194@option{once}. 195 196Interactive boot menus/prompts can be enabled via @option{menu=on} as far 197as firmware/BIOS supports them. The default is non-interactive boot. 198 199A splash picture could be passed to bios, enabling user to show it as logo, 200when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS 201supports them. Currently Seabios for X86 system support it. 202limitation: The splash file could be a jpeg file or a BMP file in 24 BPP 203format(true color). The resolution should be supported by the SVGA mode, so 204the recommended is 320x240, 640x480, 800x640. 205 206A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms 207when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not 208reboot, qemu passes '-1' to bios by default. Currently Seabios for X86 209system support it. 210 211Do strict boot via @option{strict=on} as far as firmware/BIOS 212supports it. This only effects when boot priority is changed by 213bootindex options. The default is non-strict boot. 214 215@example 216# try to boot from network first, then from hard disk 217qemu-system-i386 -boot order=nc 218# boot from CD-ROM first, switch back to default order after reboot 219qemu-system-i386 -boot once=d 220# boot with a splash picture for 5 seconds. 221qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000 222@end example 223 224Note: The legacy format '-boot @var{drives}' is still supported but its 225use is discouraged as it may be removed from future versions. 226ETEXI 227 228DEF("m", HAS_ARG, QEMU_OPTION_m, 229 "-m[emory] [size=]megs[,slots=n,maxmem=size]\n" 230 " configure guest RAM\n" 231 " size: initial amount of guest memory (default: " 232 stringify(DEFAULT_RAM_SIZE) "MiB)\n" 233 " slots: number of hotplug slots (default: none)\n" 234 " maxmem: maximum amount of guest memory (default: none)\n" 235 "NOTE: Some architectures might enforce a specific granularity\n", 236 QEMU_ARCH_ALL) 237STEXI 238@item -m [size=]@var{megs} 239@findex -m 240Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally, 241a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or 242gigabytes respectively. Optional pair @var{slots}, @var{maxmem} could be used 243to set amount of hotluggable memory slots and possible maximum amount of memory. 244ETEXI 245 246DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath, 247 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL) 248STEXI 249@item -mem-path @var{path} 250@findex -mem-path 251Allocate guest RAM from a temporarily created file in @var{path}. 252ETEXI 253 254DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc, 255 "-mem-prealloc preallocate guest memory (use with -mem-path)\n", 256 QEMU_ARCH_ALL) 257STEXI 258@item -mem-prealloc 259@findex -mem-prealloc 260Preallocate memory when using -mem-path. 261ETEXI 262 263DEF("k", HAS_ARG, QEMU_OPTION_k, 264 "-k language use keyboard layout (for example 'fr' for French)\n", 265 QEMU_ARCH_ALL) 266STEXI 267@item -k @var{language} 268@findex -k 269Use keyboard layout @var{language} (for example @code{fr} for 270French). This option is only needed where it is not easy to get raw PC 271keycodes (e.g. on Macs, with some X11 servers or with a VNC 272display). You don't normally need to use it on PC/Linux or PC/Windows 273hosts. 274 275The available layouts are: 276@example 277ar de-ch es fo fr-ca hu ja mk no pt-br sv 278da en-gb et fr fr-ch is lt nl pl ru th 279de en-us fi fr-be hr it lv nl-be pt sl tr 280@end example 281 282The default is @code{en-us}. 283ETEXI 284 285 286DEF("audio-help", 0, QEMU_OPTION_audio_help, 287 "-audio-help print list of audio drivers and their options\n", 288 QEMU_ARCH_ALL) 289STEXI 290@item -audio-help 291@findex -audio-help 292Will show the audio subsystem help: list of drivers, tunable 293parameters. 294ETEXI 295 296DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw, 297 "-soundhw c1,... enable audio support\n" 298 " and only specified sound cards (comma separated list)\n" 299 " use '-soundhw help' to get the list of supported cards\n" 300 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL) 301STEXI 302@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all 303@findex -soundhw 304Enable audio and selected sound hardware. Use 'help' to print all 305available sound hardware. 306 307@example 308qemu-system-i386 -soundhw sb16,adlib disk.img 309qemu-system-i386 -soundhw es1370 disk.img 310qemu-system-i386 -soundhw ac97 disk.img 311qemu-system-i386 -soundhw hda disk.img 312qemu-system-i386 -soundhw all disk.img 313qemu-system-i386 -soundhw help 314@end example 315 316Note that Linux's i810_audio OSS kernel (for AC97) module might 317require manually specifying clocking. 318 319@example 320modprobe i810_audio clocking=48000 321@end example 322ETEXI 323 324DEF("balloon", HAS_ARG, QEMU_OPTION_balloon, 325 "-balloon none disable balloon device\n" 326 "-balloon virtio[,addr=str]\n" 327 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL) 328STEXI 329@item -balloon none 330@findex -balloon 331Disable balloon device. 332@item -balloon virtio[,addr=@var{addr}] 333Enable virtio balloon device (default), optionally with PCI address 334@var{addr}. 335ETEXI 336 337DEF("device", HAS_ARG, QEMU_OPTION_device, 338 "-device driver[,prop[=value][,...]]\n" 339 " add device (based on driver)\n" 340 " prop=value,... sets driver properties\n" 341 " use '-device help' to print all possible drivers\n" 342 " use '-device driver,help' to print all possible properties\n", 343 QEMU_ARCH_ALL) 344STEXI 345@item -device @var{driver}[,@var{prop}[=@var{value}][,...]] 346@findex -device 347Add device @var{driver}. @var{prop}=@var{value} sets driver 348properties. Valid properties depend on the driver. To get help on 349possible drivers and properties, use @code{-device help} and 350@code{-device @var{driver},help}. 351ETEXI 352 353DEF("name", HAS_ARG, QEMU_OPTION_name, 354 "-name string1[,process=string2][,debug-threads=on|off]\n" 355 " set the name of the guest\n" 356 " string1 sets the window title and string2 the process name (on Linux)\n" 357 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n" 358 " NOTE: The thread names are for debugging and not a stable API.\n", 359 QEMU_ARCH_ALL) 360STEXI 361@item -name @var{name} 362@findex -name 363Sets the @var{name} of the guest. 364This name will be displayed in the SDL window caption. 365The @var{name} will also be used for the VNC server. 366Also optionally set the top visible process name in Linux. 367Naming of individual threads can also be enabled on Linux to aid debugging. 368ETEXI 369 370DEF("uuid", HAS_ARG, QEMU_OPTION_uuid, 371 "-uuid %08x-%04x-%04x-%04x-%012x\n" 372 " specify machine UUID\n", QEMU_ARCH_ALL) 373STEXI 374@item -uuid @var{uuid} 375@findex -uuid 376Set system UUID. 377ETEXI 378 379STEXI 380@end table 381ETEXI 382DEFHEADING() 383 384DEFHEADING(Block device options:) 385STEXI 386@table @option 387ETEXI 388 389DEF("fda", HAS_ARG, QEMU_OPTION_fda, 390 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL) 391DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL) 392STEXI 393@item -fda @var{file} 394@item -fdb @var{file} 395@findex -fda 396@findex -fdb 397Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can 398use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}). 399ETEXI 400 401DEF("hda", HAS_ARG, QEMU_OPTION_hda, 402 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL) 403DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL) 404DEF("hdc", HAS_ARG, QEMU_OPTION_hdc, 405 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL) 406DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL) 407STEXI 408@item -hda @var{file} 409@item -hdb @var{file} 410@item -hdc @var{file} 411@item -hdd @var{file} 412@findex -hda 413@findex -hdb 414@findex -hdc 415@findex -hdd 416Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}). 417ETEXI 418 419DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom, 420 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n", 421 QEMU_ARCH_ALL) 422STEXI 423@item -cdrom @var{file} 424@findex -cdrom 425Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and 426@option{-cdrom} at the same time). You can use the host CD-ROM by 427using @file{/dev/cdrom} as filename (@pxref{host_drives}). 428ETEXI 429 430DEF("drive", HAS_ARG, QEMU_OPTION_drive, 431 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" 432 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n" 433 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n" 434 " [,serial=s][,addr=A][,rerror=ignore|stop|report]\n" 435 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n" 436 " [,readonly=on|off][,copy-on-read=on|off]\n" 437 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n" 438 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n" 439 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n" 440 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n" 441 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n" 442 " [[,iops_size=is]]\n" 443 " use 'file' as a drive image\n", QEMU_ARCH_ALL) 444STEXI 445@item -drive @var{option}[,@var{option}[,@var{option}[,...]]] 446@findex -drive 447 448Define a new drive. Valid options are: 449 450@table @option 451@item file=@var{file} 452This option defines which disk image (@pxref{disk_images}) to use with 453this drive. If the filename contains comma, you must double it 454(for instance, "file=my,,file" to use file "my,file"). 455 456Special files such as iSCSI devices can be specified using protocol 457specific URLs. See the section for "Device URL Syntax" for more information. 458@item if=@var{interface} 459This option defines on which type on interface the drive is connected. 460Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio. 461@item bus=@var{bus},unit=@var{unit} 462These options define where is connected the drive by defining the bus number and 463the unit id. 464@item index=@var{index} 465This option defines where is connected the drive by using an index in the list 466of available connectors of a given interface type. 467@item media=@var{media} 468This option defines the type of the media: disk or cdrom. 469@item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}] 470These options have the same definition as they have in @option{-hdachs}. 471@item snapshot=@var{snapshot} 472@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive 473(see @option{-snapshot}). 474@item cache=@var{cache} 475@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data. 476@item aio=@var{aio} 477@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO. 478@item discard=@var{discard} 479@var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls whether @dfn{discard} (also known as @dfn{trim} or @dfn{unmap}) requests are ignored or passed to the filesystem. Some machine types may not support discard requests. 480@item format=@var{format} 481Specify which disk @var{format} will be used rather than detecting 482the format. Can be used to specifiy format=raw to avoid interpreting 483an untrusted format header. 484@item serial=@var{serial} 485This option specifies the serial number to assign to the device. 486@item addr=@var{addr} 487Specify the controller's PCI address (if=virtio only). 488@item werror=@var{action},rerror=@var{action} 489Specify which @var{action} to take on write and read errors. Valid actions are: 490"ignore" (ignore the error and try to continue), "stop" (pause QEMU), 491"report" (report the error to the guest), "enospc" (pause QEMU only if the 492host disk is full; report the error to the guest otherwise). 493The default setting is @option{werror=enospc} and @option{rerror=report}. 494@item readonly 495Open drive @option{file} as read-only. Guest write attempts will fail. 496@item copy-on-read=@var{copy-on-read} 497@var{copy-on-read} is "on" or "off" and enables whether to copy read backing 498file sectors into the image file. 499@item detect-zeroes=@var{detect-zeroes} 500@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic 501conversion of plain zero writes by the OS to driver specific optimized 502zero write commands. You may even choose "unmap" if @var{discard} is set 503to "unmap" to allow a zero write to be converted to an UNMAP operation. 504@end table 505 506By default, the @option{cache=writeback} mode is used. It will report data 507writes as completed as soon as the data is present in the host page cache. 508This is safe as long as your guest OS makes sure to correctly flush disk caches 509where needed. If your guest OS does not handle volatile disk write caches 510correctly and your host crashes or loses power, then the guest may experience 511data corruption. 512 513For such guests, you should consider using @option{cache=writethrough}. This 514means that the host page cache will be used to read and write data, but write 515notification will be sent to the guest only after QEMU has made sure to flush 516each write to the disk. Be aware that this has a major impact on performance. 517 518The host page cache can be avoided entirely with @option{cache=none}. This will 519attempt to do disk IO directly to the guest's memory. QEMU may still perform 520an internal copy of the data. Note that this is considered a writeback mode and 521the guest OS must handle the disk write cache correctly in order to avoid data 522corruption on host crashes. 523 524The host page cache can be avoided while only sending write notifications to 525the guest when the data has been flushed to the disk using 526@option{cache=directsync}. 527 528In case you don't care about data integrity over host failures, use 529@option{cache=unsafe}. This option tells QEMU that it never needs to write any 530data to the disk but can instead keep things in cache. If anything goes wrong, 531like your host losing power, the disk storage getting disconnected accidentally, 532etc. your image will most probably be rendered unusable. When using 533the @option{-snapshot} option, unsafe caching is always used. 534 535Copy-on-read avoids accessing the same backing file sectors repeatedly and is 536useful when the backing file is over a slow network. By default copy-on-read 537is off. 538 539Instead of @option{-cdrom} you can use: 540@example 541qemu-system-i386 -drive file=file,index=2,media=cdrom 542@end example 543 544Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can 545use: 546@example 547qemu-system-i386 -drive file=file,index=0,media=disk 548qemu-system-i386 -drive file=file,index=1,media=disk 549qemu-system-i386 -drive file=file,index=2,media=disk 550qemu-system-i386 -drive file=file,index=3,media=disk 551@end example 552 553You can open an image using pre-opened file descriptors from an fd set: 554@example 555qemu-system-i386 556-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 557-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 558-drive file=/dev/fdset/2,index=0,media=disk 559@end example 560 561You can connect a CDROM to the slave of ide0: 562@example 563qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom 564@end example 565 566If you don't specify the "file=" argument, you define an empty drive: 567@example 568qemu-system-i386 -drive if=ide,index=1,media=cdrom 569@end example 570 571You can connect a SCSI disk with unit ID 6 on the bus #0: 572@example 573qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6 574@end example 575 576Instead of @option{-fda}, @option{-fdb}, you can use: 577@example 578qemu-system-i386 -drive file=file,index=0,if=floppy 579qemu-system-i386 -drive file=file,index=1,if=floppy 580@end example 581 582By default, @var{interface} is "ide" and @var{index} is automatically 583incremented: 584@example 585qemu-system-i386 -drive file=a -drive file=b" 586@end example 587is interpreted like: 588@example 589qemu-system-i386 -hda a -hdb b 590@end example 591ETEXI 592 593DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock, 594 "-mtdblock file use 'file' as on-board Flash memory image\n", 595 QEMU_ARCH_ALL) 596STEXI 597@item -mtdblock @var{file} 598@findex -mtdblock 599Use @var{file} as on-board Flash memory image. 600ETEXI 601 602DEF("sd", HAS_ARG, QEMU_OPTION_sd, 603 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL) 604STEXI 605@item -sd @var{file} 606@findex -sd 607Use @var{file} as SecureDigital card image. 608ETEXI 609 610DEF("pflash", HAS_ARG, QEMU_OPTION_pflash, 611 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL) 612STEXI 613@item -pflash @var{file} 614@findex -pflash 615Use @var{file} as a parallel flash image. 616ETEXI 617 618DEF("snapshot", 0, QEMU_OPTION_snapshot, 619 "-snapshot write to temporary files instead of disk image files\n", 620 QEMU_ARCH_ALL) 621STEXI 622@item -snapshot 623@findex -snapshot 624Write to temporary files instead of disk image files. In this case, 625the raw disk image you use is not written back. You can however force 626the write back by pressing @key{C-a s} (@pxref{disk_images}). 627ETEXI 628 629DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \ 630 "-hdachs c,h,s[,t]\n" \ 631 " force hard disk 0 physical geometry and the optional BIOS\n" \ 632 " translation (t=none or lba) (usually QEMU can guess them)\n", 633 QEMU_ARCH_ALL) 634STEXI 635@item -hdachs @var{c},@var{h},@var{s},[,@var{t}] 636@findex -hdachs 637Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <= 638@var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS 639translation mode (@var{t}=none, lba or auto). Usually QEMU can guess 640all those parameters. This option is useful for old MS-DOS disk 641images. 642ETEXI 643 644DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev, 645 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n" 646 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n", 647 QEMU_ARCH_ALL) 648 649STEXI 650 651@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}] 652@findex -fsdev 653Define a new file system device. Valid options are: 654@table @option 655@item @var{fsdriver} 656This option specifies the fs driver backend to use. 657Currently "local", "handle" and "proxy" file system drivers are supported. 658@item id=@var{id} 659Specifies identifier for this device 660@item path=@var{path} 661Specifies the export path for the file system device. Files under 662this path will be available to the 9p client on the guest. 663@item security_model=@var{security_model} 664Specifies the security model to be used for this export path. 665Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 666In "passthrough" security model, files are stored using the same 667credentials as they are created on the guest. This requires QEMU 668to run as root. In "mapped-xattr" security model, some of the file 669attributes like uid, gid, mode bits and link target are stored as 670file attributes. For "mapped-file" these attributes are stored in the 671hidden .virtfs_metadata directory. Directories exported by this security model cannot 672interact with other unix tools. "none" security model is same as 673passthrough except the sever won't report failures if it fails to 674set file attributes like ownership. Security model is mandatory 675only for local fsdriver. Other fsdrivers (like handle, proxy) don't take 676security model as a parameter. 677@item writeout=@var{writeout} 678This is an optional argument. The only supported value is "immediate". 679This means that host page cache will be used to read and write data but 680write notification will be sent to the guest only when the data has been 681reported as written by the storage subsystem. 682@item readonly 683Enables exporting 9p share as a readonly mount for guests. By default 684read-write access is given. 685@item socket=@var{socket} 686Enables proxy filesystem driver to use passed socket file for communicating 687with virtfs-proxy-helper 688@item sock_fd=@var{sock_fd} 689Enables proxy filesystem driver to use passed socket descriptor for 690communicating with virtfs-proxy-helper. Usually a helper like libvirt 691will create socketpair and pass one of the fds as sock_fd 692@end table 693 694-fsdev option is used along with -device driver "virtio-9p-pci". 695@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag} 696Options for virtio-9p-pci driver are: 697@table @option 698@item fsdev=@var{id} 699Specifies the id value specified along with -fsdev option 700@item mount_tag=@var{mount_tag} 701Specifies the tag name to be used by the guest to mount this export point 702@end table 703 704ETEXI 705 706DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs, 707 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n" 708 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n", 709 QEMU_ARCH_ALL) 710 711STEXI 712 713@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}] 714@findex -virtfs 715 716The general form of a Virtual File system pass-through options are: 717@table @option 718@item @var{fsdriver} 719This option specifies the fs driver backend to use. 720Currently "local", "handle" and "proxy" file system drivers are supported. 721@item id=@var{id} 722Specifies identifier for this device 723@item path=@var{path} 724Specifies the export path for the file system device. Files under 725this path will be available to the 9p client on the guest. 726@item security_model=@var{security_model} 727Specifies the security model to be used for this export path. 728Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 729In "passthrough" security model, files are stored using the same 730credentials as they are created on the guest. This requires QEMU 731to run as root. In "mapped-xattr" security model, some of the file 732attributes like uid, gid, mode bits and link target are stored as 733file attributes. For "mapped-file" these attributes are stored in the 734hidden .virtfs_metadata directory. Directories exported by this security model cannot 735interact with other unix tools. "none" security model is same as 736passthrough except the sever won't report failures if it fails to 737set file attributes like ownership. Security model is mandatory only 738for local fsdriver. Other fsdrivers (like handle, proxy) don't take security 739model as a parameter. 740@item writeout=@var{writeout} 741This is an optional argument. The only supported value is "immediate". 742This means that host page cache will be used to read and write data but 743write notification will be sent to the guest only when the data has been 744reported as written by the storage subsystem. 745@item readonly 746Enables exporting 9p share as a readonly mount for guests. By default 747read-write access is given. 748@item socket=@var{socket} 749Enables proxy filesystem driver to use passed socket file for 750communicating with virtfs-proxy-helper. Usually a helper like libvirt 751will create socketpair and pass one of the fds as sock_fd 752@item sock_fd 753Enables proxy filesystem driver to use passed 'sock_fd' as the socket 754descriptor for interfacing with virtfs-proxy-helper 755@end table 756ETEXI 757 758DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth, 759 "-virtfs_synth Create synthetic file system image\n", 760 QEMU_ARCH_ALL) 761STEXI 762@item -virtfs_synth 763@findex -virtfs_synth 764Create synthetic file system image 765ETEXI 766 767STEXI 768@end table 769ETEXI 770DEFHEADING() 771 772DEFHEADING(USB options:) 773STEXI 774@table @option 775ETEXI 776 777DEF("usb", 0, QEMU_OPTION_usb, 778 "-usb enable the USB driver (will be the default soon)\n", 779 QEMU_ARCH_ALL) 780STEXI 781@item -usb 782@findex -usb 783Enable the USB driver (will be the default soon) 784ETEXI 785 786DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice, 787 "-usbdevice name add the host or guest USB device 'name'\n", 788 QEMU_ARCH_ALL) 789STEXI 790 791@item -usbdevice @var{devname} 792@findex -usbdevice 793Add the USB device @var{devname}. @xref{usb_devices}. 794 795@table @option 796 797@item mouse 798Virtual Mouse. This will override the PS/2 mouse emulation when activated. 799 800@item tablet 801Pointer device that uses absolute coordinates (like a touchscreen). This 802means QEMU is able to report the mouse position without having to grab the 803mouse. Also overrides the PS/2 mouse emulation when activated. 804 805@item disk:[format=@var{format}]:@var{file} 806Mass storage device based on file. The optional @var{format} argument 807will be used rather than detecting the format. Can be used to specifiy 808@code{format=raw} to avoid interpreting an untrusted format header. 809 810@item host:@var{bus}.@var{addr} 811Pass through the host device identified by @var{bus}.@var{addr} (Linux only). 812 813@item host:@var{vendor_id}:@var{product_id} 814Pass through the host device identified by @var{vendor_id}:@var{product_id} 815(Linux only). 816 817@item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev} 818Serial converter to host character device @var{dev}, see @code{-serial} for the 819available devices. 820 821@item braille 822Braille device. This will use BrlAPI to display the braille output on a real 823or fake device. 824 825@item net:@var{options} 826Network adapter that supports CDC ethernet and RNDIS protocols. 827 828@end table 829ETEXI 830 831STEXI 832@end table 833ETEXI 834DEFHEADING() 835 836DEFHEADING(Display options:) 837STEXI 838@table @option 839ETEXI 840 841DEF("display", HAS_ARG, QEMU_OPTION_display, 842 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n" 843 " [,window_close=on|off]|curses|none|\n" 844 " gtk[,grab_on_hover=on|off]|\n" 845 " vnc=<display>[,<optargs>]\n" 846 " select display type\n", QEMU_ARCH_ALL) 847STEXI 848@item -display @var{type} 849@findex -display 850Select type of display to use. This option is a replacement for the 851old style -sdl/-curses/... options. Valid values for @var{type} are 852@table @option 853@item sdl 854Display video output via SDL (usually in a separate graphics 855window; see the SDL documentation for other possibilities). 856@item curses 857Display video output via curses. For graphics device models which 858support a text mode, QEMU can display this output using a 859curses/ncurses interface. Nothing is displayed when the graphics 860device is in graphical mode or if the graphics device does not support 861a text mode. Generally only the VGA device models support text mode. 862@item none 863Do not display video output. The guest will still see an emulated 864graphics card, but its output will not be displayed to the QEMU 865user. This option differs from the -nographic option in that it 866only affects what is done with video output; -nographic also changes 867the destination of the serial and parallel port data. 868@item gtk 869Display video output in a GTK window. This interface provides drop-down 870menus and other UI elements to configure and control the VM during 871runtime. 872@item vnc 873Start a VNC server on display <arg> 874@end table 875ETEXI 876 877DEF("nographic", 0, QEMU_OPTION_nographic, 878 "-nographic disable graphical output and redirect serial I/Os to console\n", 879 QEMU_ARCH_ALL) 880STEXI 881@item -nographic 882@findex -nographic 883Normally, QEMU uses SDL to display the VGA output. With this option, 884you can totally disable graphical output so that QEMU is a simple 885command line application. The emulated serial port is redirected on 886the console and muxed with the monitor (unless redirected elsewhere 887explicitly). Therefore, you can still use QEMU to debug a Linux kernel 888with a serial console. Use @key{C-a h} for help on switching between 889the console and monitor. 890ETEXI 891 892DEF("curses", 0, QEMU_OPTION_curses, 893 "-curses use a curses/ncurses interface instead of SDL\n", 894 QEMU_ARCH_ALL) 895STEXI 896@item -curses 897@findex -curses 898Normally, QEMU uses SDL to display the VGA output. With this option, 899QEMU can display the VGA output when in text mode using a 900curses/ncurses interface. Nothing is displayed in graphical mode. 901ETEXI 902 903DEF("no-frame", 0, QEMU_OPTION_no_frame, 904 "-no-frame open SDL window without a frame and window decorations\n", 905 QEMU_ARCH_ALL) 906STEXI 907@item -no-frame 908@findex -no-frame 909Do not use decorations for SDL windows and start them using the whole 910available screen space. This makes the using QEMU in a dedicated desktop 911workspace more convenient. 912ETEXI 913 914DEF("alt-grab", 0, QEMU_OPTION_alt_grab, 915 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n", 916 QEMU_ARCH_ALL) 917STEXI 918@item -alt-grab 919@findex -alt-grab 920Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also 921affects the special keys (for fullscreen, monitor-mode switching, etc). 922ETEXI 923 924DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab, 925 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n", 926 QEMU_ARCH_ALL) 927STEXI 928@item -ctrl-grab 929@findex -ctrl-grab 930Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also 931affects the special keys (for fullscreen, monitor-mode switching, etc). 932ETEXI 933 934DEF("no-quit", 0, QEMU_OPTION_no_quit, 935 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL) 936STEXI 937@item -no-quit 938@findex -no-quit 939Disable SDL window close capability. 940ETEXI 941 942DEF("sdl", 0, QEMU_OPTION_sdl, 943 "-sdl enable SDL\n", QEMU_ARCH_ALL) 944STEXI 945@item -sdl 946@findex -sdl 947Enable SDL. 948ETEXI 949 950DEF("spice", HAS_ARG, QEMU_OPTION_spice, 951 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n" 952 " [,x509-key-file=<file>][,x509-key-password=<file>]\n" 953 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n" 954 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6]\n" 955 " [,tls-ciphers=<list>]\n" 956 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n" 957 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n" 958 " [,sasl][,password=<secret>][,disable-ticketing]\n" 959 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n" 960 " [,jpeg-wan-compression=[auto|never|always]]\n" 961 " [,zlib-glz-wan-compression=[auto|never|always]]\n" 962 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n" 963 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n" 964 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n" 965 " enable spice\n" 966 " at least one of {port, tls-port} is mandatory\n", 967 QEMU_ARCH_ALL) 968STEXI 969@item -spice @var{option}[,@var{option}[,...]] 970@findex -spice 971Enable the spice remote desktop protocol. Valid options are 972 973@table @option 974 975@item port=<nr> 976Set the TCP port spice is listening on for plaintext channels. 977 978@item addr=<addr> 979Set the IP address spice is listening on. Default is any address. 980 981@item ipv4 982@item ipv6 983Force using the specified IP version. 984 985@item password=<secret> 986Set the password you need to authenticate. 987 988@item sasl 989Require that the client use SASL to authenticate with the spice. 990The exact choice of authentication method used is controlled from the 991system / user's SASL configuration file for the 'qemu' service. This 992is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 993unprivileged user, an environment variable SASL_CONF_PATH can be used 994to make it search alternate locations for the service config. 995While some SASL auth methods can also provide data encryption (eg GSSAPI), 996it is recommended that SASL always be combined with the 'tls' and 997'x509' settings to enable use of SSL and server certificates. This 998ensures a data encryption preventing compromise of authentication 999credentials. 1000 1001@item disable-ticketing 1002Allow client connects without authentication. 1003 1004@item disable-copy-paste 1005Disable copy paste between the client and the guest. 1006 1007@item disable-agent-file-xfer 1008Disable spice-vdagent based file-xfer between the client and the guest. 1009 1010@item tls-port=<nr> 1011Set the TCP port spice is listening on for encrypted channels. 1012 1013@item x509-dir=<dir> 1014Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir 1015 1016@item x509-key-file=<file> 1017@item x509-key-password=<file> 1018@item x509-cert-file=<file> 1019@item x509-cacert-file=<file> 1020@item x509-dh-key-file=<file> 1021The x509 file names can also be configured individually. 1022 1023@item tls-ciphers=<list> 1024Specify which ciphers to use. 1025 1026@item tls-channel=[main|display|cursor|inputs|record|playback] 1027@item plaintext-channel=[main|display|cursor|inputs|record|playback] 1028Force specific channel to be used with or without TLS encryption. The 1029options can be specified multiple times to configure multiple 1030channels. The special name "default" can be used to set the default 1031mode. For channels which are not explicitly forced into one mode the 1032spice client is allowed to pick tls/plaintext as he pleases. 1033 1034@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off] 1035Configure image compression (lossless). 1036Default is auto_glz. 1037 1038@item jpeg-wan-compression=[auto|never|always] 1039@item zlib-glz-wan-compression=[auto|never|always] 1040Configure wan image compression (lossy for slow links). 1041Default is auto. 1042 1043@item streaming-video=[off|all|filter] 1044Configure video stream detection. Default is filter. 1045 1046@item agent-mouse=[on|off] 1047Enable/disable passing mouse events via vdagent. Default is on. 1048 1049@item playback-compression=[on|off] 1050Enable/disable audio stream compression (using celt 0.5.1). Default is on. 1051 1052@item seamless-migration=[on|off] 1053Enable/disable spice seamless migration. Default is off. 1054 1055@end table 1056ETEXI 1057 1058DEF("portrait", 0, QEMU_OPTION_portrait, 1059 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n", 1060 QEMU_ARCH_ALL) 1061STEXI 1062@item -portrait 1063@findex -portrait 1064Rotate graphical output 90 deg left (only PXA LCD). 1065ETEXI 1066 1067DEF("rotate", HAS_ARG, QEMU_OPTION_rotate, 1068 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n", 1069 QEMU_ARCH_ALL) 1070STEXI 1071@item -rotate @var{deg} 1072@findex -rotate 1073Rotate graphical output some deg left (only PXA LCD). 1074ETEXI 1075 1076DEF("vga", HAS_ARG, QEMU_OPTION_vga, 1077 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|none]\n" 1078 " select video card type\n", QEMU_ARCH_ALL) 1079STEXI 1080@item -vga @var{type} 1081@findex -vga 1082Select type of VGA card to emulate. Valid values for @var{type} are 1083@table @option 1084@item cirrus 1085Cirrus Logic GD5446 Video card. All Windows versions starting from 1086Windows 95 should recognize and use this graphic card. For optimal 1087performances, use 16 bit color depth in the guest and the host OS. 1088(This one is the default) 1089@item std 1090Standard VGA card with Bochs VBE extensions. If your guest OS 1091supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want 1092to use high resolution modes (>= 1280x1024x16) then you should use 1093this option. 1094@item vmware 1095VMWare SVGA-II compatible adapter. Use it if you have sufficiently 1096recent XFree86/XOrg server or Windows guest with a driver for this 1097card. 1098@item qxl 1099QXL paravirtual graphic card. It is VGA compatible (including VESA 11002.0 VBE support). Works best with qxl guest drivers installed though. 1101Recommended choice when using the spice protocol. 1102@item tcx 1103(sun4m only) Sun TCX framebuffer. This is the default framebuffer for 1104sun4m machines and offers both 8-bit and 24-bit colour depths at a 1105fixed resolution of 1024x768. 1106@item cg3 1107(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer 1108for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP) 1109resolutions aimed at people wishing to run older Solaris versions. 1110@item none 1111Disable VGA card. 1112@end table 1113ETEXI 1114 1115DEF("full-screen", 0, QEMU_OPTION_full_screen, 1116 "-full-screen start in full screen\n", QEMU_ARCH_ALL) 1117STEXI 1118@item -full-screen 1119@findex -full-screen 1120Start in full screen. 1121ETEXI 1122 1123DEF("g", 1, QEMU_OPTION_g , 1124 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n", 1125 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 1126STEXI 1127@item -g @var{width}x@var{height}[x@var{depth}] 1128@findex -g 1129Set the initial graphical resolution and depth (PPC, SPARC only). 1130ETEXI 1131 1132DEF("vnc", HAS_ARG, QEMU_OPTION_vnc , 1133 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL) 1134STEXI 1135@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]] 1136@findex -vnc 1137Normally, QEMU uses SDL to display the VGA output. With this option, 1138you can have QEMU listen on VNC display @var{display} and redirect the VGA 1139display over the VNC session. It is very useful to enable the usb 1140tablet device when using this option (option @option{-usbdevice 1141tablet}). When using the VNC display, you must use the @option{-k} 1142parameter to set the keyboard layout if you are not using en-us. Valid 1143syntax for the @var{display} is 1144 1145@table @option 1146 1147@item @var{host}:@var{d} 1148 1149TCP connections will only be allowed from @var{host} on display @var{d}. 1150By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can 1151be omitted in which case the server will accept connections from any host. 1152 1153@item unix:@var{path} 1154 1155Connections will be allowed over UNIX domain sockets where @var{path} is the 1156location of a unix socket to listen for connections on. 1157 1158@item none 1159 1160VNC is initialized but not started. The monitor @code{change} command 1161can be used to later start the VNC server. 1162 1163@end table 1164 1165Following the @var{display} value there may be one or more @var{option} flags 1166separated by commas. Valid options are 1167 1168@table @option 1169 1170@item reverse 1171 1172Connect to a listening VNC client via a ``reverse'' connection. The 1173client is specified by the @var{display}. For reverse network 1174connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument 1175is a TCP port number, not a display number. 1176 1177@item websocket 1178 1179Opens an additional TCP listening port dedicated to VNC Websocket connections. 1180By definition the Websocket port is 5700+@var{display}. If @var{host} is 1181specified connections will only be allowed from this host. 1182As an alternative the Websocket port could be specified by using 1183@code{websocket}=@var{port}. 1184TLS encryption for the Websocket connection is supported if the required 1185certificates are specified with the VNC option @option{x509}. 1186 1187@item password 1188 1189Require that password based authentication is used for client connections. 1190 1191The password must be set separately using the @code{set_password} command in 1192the @ref{pcsys_monitor}. The syntax to change your password is: 1193@code{set_password <protocol> <password>} where <protocol> could be either 1194"vnc" or "spice". 1195 1196If you would like to change <protocol> password expiration, you should use 1197@code{expire_password <protocol> <expiration-time>} where expiration time could 1198be one of the following options: now, never, +seconds or UNIX time of 1199expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800 1200to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this 1201date and time). 1202 1203You can also use keywords "now" or "never" for the expiration time to 1204allow <protocol> password to expire immediately or never expire. 1205 1206@item tls 1207 1208Require that client use TLS when communicating with the VNC server. This 1209uses anonymous TLS credentials so is susceptible to a man-in-the-middle 1210attack. It is recommended that this option be combined with either the 1211@option{x509} or @option{x509verify} options. 1212 1213@item x509=@var{/path/to/certificate/dir} 1214 1215Valid if @option{tls} is specified. Require that x509 credentials are used 1216for negotiating the TLS session. The server will send its x509 certificate 1217to the client. It is recommended that a password be set on the VNC server 1218to provide authentication of the client when this is used. The path following 1219this option specifies where the x509 certificates are to be loaded from. 1220See the @ref{vnc_security} section for details on generating certificates. 1221 1222@item x509verify=@var{/path/to/certificate/dir} 1223 1224Valid if @option{tls} is specified. Require that x509 credentials are used 1225for negotiating the TLS session. The server will send its x509 certificate 1226to the client, and request that the client send its own x509 certificate. 1227The server will validate the client's certificate against the CA certificate, 1228and reject clients when validation fails. If the certificate authority is 1229trusted, this is a sufficient authentication mechanism. You may still wish 1230to set a password on the VNC server as a second authentication layer. The 1231path following this option specifies where the x509 certificates are to 1232be loaded from. See the @ref{vnc_security} section for details on generating 1233certificates. 1234 1235@item sasl 1236 1237Require that the client use SASL to authenticate with the VNC server. 1238The exact choice of authentication method used is controlled from the 1239system / user's SASL configuration file for the 'qemu' service. This 1240is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1241unprivileged user, an environment variable SASL_CONF_PATH can be used 1242to make it search alternate locations for the service config. 1243While some SASL auth methods can also provide data encryption (eg GSSAPI), 1244it is recommended that SASL always be combined with the 'tls' and 1245'x509' settings to enable use of SSL and server certificates. This 1246ensures a data encryption preventing compromise of authentication 1247credentials. See the @ref{vnc_security} section for details on using 1248SASL authentication. 1249 1250@item acl 1251 1252Turn on access control lists for checking of the x509 client certificate 1253and SASL party. For x509 certs, the ACL check is made against the 1254certificate's distinguished name. This is something that looks like 1255@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is 1256made against the username, which depending on the SASL plugin, may 1257include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}. 1258When the @option{acl} flag is set, the initial access list will be 1259empty, with a @code{deny} policy. Thus no one will be allowed to 1260use the VNC server until the ACLs have been loaded. This can be 1261achieved using the @code{acl} monitor command. 1262 1263@item lossy 1264 1265Enable lossy compression methods (gradient, JPEG, ...). If this 1266option is set, VNC client may receive lossy framebuffer updates 1267depending on its encoding settings. Enabling this option can save 1268a lot of bandwidth at the expense of quality. 1269 1270@item non-adaptive 1271 1272Disable adaptive encodings. Adaptive encodings are enabled by default. 1273An adaptive encoding will try to detect frequently updated screen regions, 1274and send updates in these regions using a lossy encoding (like JPEG). 1275This can be really helpful to save bandwidth when playing videos. Disabling 1276adaptive encodings restores the original static behavior of encodings 1277like Tight. 1278 1279@item share=[allow-exclusive|force-shared|ignore] 1280 1281Set display sharing policy. 'allow-exclusive' allows clients to ask 1282for exclusive access. As suggested by the rfb spec this is 1283implemented by dropping other connections. Connecting multiple 1284clients in parallel requires all clients asking for a shared session 1285(vncviewer: -shared switch). This is the default. 'force-shared' 1286disables exclusive client access. Useful for shared desktop sessions, 1287where you don't want someone forgetting specify -shared disconnect 1288everybody else. 'ignore' completely ignores the shared flag and 1289allows everybody connect unconditionally. Doesn't conform to the rfb 1290spec but is traditional QEMU behavior. 1291 1292@end table 1293ETEXI 1294 1295STEXI 1296@end table 1297ETEXI 1298ARCHHEADING(, QEMU_ARCH_I386) 1299 1300ARCHHEADING(i386 target only:, QEMU_ARCH_I386) 1301STEXI 1302@table @option 1303ETEXI 1304 1305DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack, 1306 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n", 1307 QEMU_ARCH_I386) 1308STEXI 1309@item -win2k-hack 1310@findex -win2k-hack 1311Use it when installing Windows 2000 to avoid a disk full bug. After 1312Windows 2000 is installed, you no longer need this option (this option 1313slows down the IDE transfers). 1314ETEXI 1315 1316HXCOMM Deprecated by -rtc 1317DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386) 1318 1319DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk, 1320 "-no-fd-bootchk disable boot signature checking for floppy disks\n", 1321 QEMU_ARCH_I386) 1322STEXI 1323@item -no-fd-bootchk 1324@findex -no-fd-bootchk 1325Disable boot signature checking for floppy disks in BIOS. May 1326be needed to boot from old floppy disks. 1327ETEXI 1328 1329DEF("no-acpi", 0, QEMU_OPTION_no_acpi, 1330 "-no-acpi disable ACPI\n", QEMU_ARCH_I386) 1331STEXI 1332@item -no-acpi 1333@findex -no-acpi 1334Disable ACPI (Advanced Configuration and Power Interface) support. Use 1335it if your guest OS complains about ACPI problems (PC target machine 1336only). 1337ETEXI 1338 1339DEF("no-hpet", 0, QEMU_OPTION_no_hpet, 1340 "-no-hpet disable HPET\n", QEMU_ARCH_I386) 1341STEXI 1342@item -no-hpet 1343@findex -no-hpet 1344Disable HPET support. 1345ETEXI 1346 1347DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable, 1348 "-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" 1349 " ACPI table description\n", QEMU_ARCH_I386) 1350STEXI 1351@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}]...] 1352@findex -acpitable 1353Add ACPI table with specified header fields and context from specified files. 1354For file=, take whole ACPI table from the specified files, including all 1355ACPI headers (possible overridden by other options). 1356For data=, only data 1357portion of the table is used, all header information is specified in the 1358command line. 1359ETEXI 1360 1361DEF("smbios", HAS_ARG, QEMU_OPTION_smbios, 1362 "-smbios file=binary\n" 1363 " load SMBIOS entry from binary file\n" 1364 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d][,uefi=on|off]\n" 1365 " specify SMBIOS type 0 fields\n" 1366 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1367 " [,uuid=uuid][,sku=str][,family=str]\n" 1368 " specify SMBIOS type 1 fields\n", QEMU_ARCH_I386) 1369STEXI 1370@item -smbios file=@var{binary} 1371@findex -smbios 1372Load SMBIOS entry from binary file. 1373 1374@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off] 1375Specify SMBIOS type 0 fields 1376 1377@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}] 1378Specify SMBIOS type 1 fields 1379ETEXI 1380 1381STEXI 1382@end table 1383ETEXI 1384DEFHEADING() 1385 1386DEFHEADING(Network options:) 1387STEXI 1388@table @option 1389ETEXI 1390 1391HXCOMM Legacy slirp options (now moved to -net user): 1392#ifdef CONFIG_SLIRP 1393DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL) 1394DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL) 1395DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL) 1396#ifndef _WIN32 1397DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL) 1398#endif 1399#endif 1400 1401DEF("net", HAS_ARG, QEMU_OPTION_net, 1402 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n" 1403 " create a new Network Interface Card and connect it to VLAN 'n'\n" 1404#ifdef CONFIG_SLIRP 1405 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=on|off]\n" 1406 " [,hostname=host][,dhcpstart=addr][,dns=addr][,dnssearch=domain][,tftp=dir]\n" 1407 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]" 1408#ifndef _WIN32 1409 "[,smb=dir[,smbserver=addr]]\n" 1410#endif 1411 " connect the user mode network stack to VLAN 'n', configure its\n" 1412 " DHCP server and enabled optional services\n" 1413#endif 1414#ifdef _WIN32 1415 "-net tap[,vlan=n][,name=str],ifname=name\n" 1416 " connect the host TAP network interface to VLAN 'n'\n" 1417#else 1418 "-net tap[,vlan=n][,name=str][,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off][,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n" 1419 " connect the host TAP network interface to VLAN 'n'\n" 1420 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n" 1421 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n" 1422 " to deconfigure it\n" 1423 " use '[down]script=no' to disable script execution\n" 1424 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n" 1425 " configure it\n" 1426 " use 'fd=h' to connect to an already opened TAP interface\n" 1427 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n" 1428 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n" 1429 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n" 1430 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n" 1431 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" 1432 " use vhost=on to enable experimental in kernel accelerator\n" 1433 " (only has effect for virtio guests which use MSIX)\n" 1434 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n" 1435 " use 'vhostfd=h' to connect to an already opened vhost net device\n" 1436 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n" 1437 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n" 1438 "-net bridge[,vlan=n][,name=str][,br=bridge][,helper=helper]\n" 1439 " connects a host TAP network interface to a host bridge device 'br'\n" 1440 " (default=" DEFAULT_BRIDGE_INTERFACE ") using the program 'helper'\n" 1441 " (default=" DEFAULT_BRIDGE_HELPER ")\n" 1442#endif 1443#ifdef __linux__ 1444 "-net l2tpv3[,vlan=n][,name=str],src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport],txsession=txsession[,rxsession=rxsession][,ipv6=on/off][,udp=on/off][,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie][,rxcookie=rxcookie][,offset=offset]\n" 1445 " connect the VLAN to an Ethernet over L2TPv3 pseudowire\n" 1446 " Linux kernel 3.3+ as well as most routers can talk\n" 1447 " L2TPv3. This transport allows connecting a VM to a VM,\n" 1448 " VM to a router and even VM to Host. It is a nearly-universal\n" 1449 " standard (RFC3391). Note - this implementation uses static\n" 1450 " pre-configured tunnels (same as the Linux kernel).\n" 1451 " use 'src=' to specify source address\n" 1452 " use 'dst=' to specify destination address\n" 1453 " use 'udp=on' to specify udp encapsulation\n" 1454 " use 'srcport=' to specify source udp port\n" 1455 " use 'dstport=' to specify destination udp port\n" 1456 " use 'ipv6=on' to force v6\n" 1457 " L2TPv3 uses cookies to prevent misconfiguration as\n" 1458 " well as a weak security measure\n" 1459 " use 'rxcookie=0x012345678' to specify a rxcookie\n" 1460 " use 'txcookie=0x012345678' to specify a txcookie\n" 1461 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n" 1462 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n" 1463 " use 'pincounter=on' to work around broken counter handling in peer\n" 1464 " use 'offset=X' to add an extra offset between header and data\n" 1465#endif 1466 "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n" 1467 " connect the vlan 'n' to another VLAN using a socket connection\n" 1468 "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port[,localaddr=addr]]\n" 1469 " connect the vlan 'n' to multicast maddr and port\n" 1470 " use 'localaddr=addr' to specify the host address to send packets from\n" 1471 "-net socket[,vlan=n][,name=str][,fd=h][,udp=host:port][,localaddr=host:port]\n" 1472 " connect the vlan 'n' to another VLAN using an UDP tunnel\n" 1473#ifdef CONFIG_VDE 1474 "-net vde[,vlan=n][,name=str][,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n" 1475 " connect the vlan 'n' to port 'n' of a vde switch running\n" 1476 " on host and listening for incoming connections on 'socketpath'.\n" 1477 " Use group 'groupname' and mode 'octalmode' to change default\n" 1478 " ownership and permissions for communication port.\n" 1479#endif 1480#ifdef CONFIG_NETMAP 1481 "-net netmap,ifname=name[,devname=nmname]\n" 1482 " attach to the existing netmap-enabled network interface 'name', or to a\n" 1483 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n" 1484 " netmap device, defaults to '/dev/netmap')\n" 1485#endif 1486 "-net dump[,vlan=n][,file=f][,len=n]\n" 1487 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n" 1488 "-net none use it alone to have zero network devices. If no -net option\n" 1489 " is provided, the default is '-net nic -net user'\n", QEMU_ARCH_ALL) 1490DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, 1491 "-netdev [" 1492#ifdef CONFIG_SLIRP 1493 "user|" 1494#endif 1495 "tap|" 1496 "bridge|" 1497#ifdef CONFIG_VDE 1498 "vde|" 1499#endif 1500#ifdef CONFIG_NETMAP 1501 "netmap|" 1502#endif 1503 "vhost-user|" 1504 "socket|" 1505 "hubport],id=str[,option][,option][,...]\n", QEMU_ARCH_ALL) 1506STEXI 1507@item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}] 1508@findex -net 1509Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n} 1510= 0 is the default). The NIC is an e1000 by default on the PC 1511target. Optionally, the MAC address can be changed to @var{mac}, the 1512device address set to @var{addr} (PCI cards only), 1513and a @var{name} can be assigned for use in monitor commands. 1514Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors 1515that the card should have; this option currently only affects virtio cards; set 1516@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single 1517NIC is created. QEMU can emulate several different models of network card. 1518Valid values for @var{type} are 1519@code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er}, 1520@code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139}, 1521@code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}. 1522Not all devices are supported on all targets. Use @code{-net nic,model=help} 1523for a list of available devices for your target. 1524 1525@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...] 1526@findex -netdev 1527@item -net user[,@var{option}][,@var{option}][,...] 1528Use the user mode network stack which requires no administrator 1529privilege to run. Valid options are: 1530 1531@table @option 1532@item vlan=@var{n} 1533Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default). 1534 1535@item id=@var{id} 1536@item name=@var{name} 1537Assign symbolic name for use in monitor commands. 1538 1539@item net=@var{addr}[/@var{mask}] 1540Set IP network address the guest will see. Optionally specify the netmask, 1541either in the form a.b.c.d or as number of valid top-most bits. Default is 154210.0.2.0/24. 1543 1544@item host=@var{addr} 1545Specify the guest-visible address of the host. Default is the 2nd IP in the 1546guest network, i.e. x.x.x.2. 1547 1548@item restrict=on|off 1549If this option is enabled, the guest will be isolated, i.e. it will not be 1550able to contact the host and no guest IP packets will be routed over the host 1551to the outside. This option does not affect any explicitly set forwarding rules. 1552 1553@item hostname=@var{name} 1554Specifies the client hostname reported by the built-in DHCP server. 1555 1556@item dhcpstart=@var{addr} 1557Specify the first of the 16 IPs the built-in DHCP server can assign. Default 1558is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31. 1559 1560@item dns=@var{addr} 1561Specify the guest-visible address of the virtual nameserver. The address must 1562be different from the host address. Default is the 3rd IP in the guest network, 1563i.e. x.x.x.3. 1564 1565@item dnssearch=@var{domain} 1566Provides an entry for the domain-search list sent by the built-in 1567DHCP server. More than one domain suffix can be transmitted by specifying 1568this option multiple times. If supported, this will cause the guest to 1569automatically try to append the given domain suffix(es) in case a domain name 1570can not be resolved. 1571 1572Example: 1573@example 1574qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...] 1575@end example 1576 1577@item tftp=@var{dir} 1578When using the user mode network stack, activate a built-in TFTP 1579server. The files in @var{dir} will be exposed as the root of a TFTP server. 1580The TFTP client on the guest must be configured in binary mode (use the command 1581@code{bin} of the Unix TFTP client). 1582 1583@item bootfile=@var{file} 1584When using the user mode network stack, broadcast @var{file} as the BOOTP 1585filename. In conjunction with @option{tftp}, this can be used to network boot 1586a guest from a local directory. 1587 1588Example (using pxelinux): 1589@example 1590qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0 1591@end example 1592 1593@item smb=@var{dir}[,smbserver=@var{addr}] 1594When using the user mode network stack, activate a built-in SMB 1595server so that Windows OSes can access to the host files in @file{@var{dir}} 1596transparently. The IP address of the SMB server can be set to @var{addr}. By 1597default the 4th IP in the guest network is used, i.e. x.x.x.4. 1598 1599In the guest Windows OS, the line: 1600@example 160110.0.2.4 smbserver 1602@end example 1603must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me) 1604or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000). 1605 1606Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}. 1607 1608Note that a SAMBA server must be installed on the host OS. 1609QEMU was tested successfully with smbd versions from Red Hat 9, 1610Fedora Core 3 and OpenSUSE 11.x. 1611 1612@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport} 1613Redirect incoming TCP or UDP connections to the host port @var{hostport} to 1614the guest IP address @var{guestaddr} on guest port @var{guestport}. If 1615@var{guestaddr} is not specified, its value is x.x.x.15 (default first address 1616given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can 1617be bound to a specific host interface. If no connection type is set, TCP is 1618used. This option can be given multiple times. 1619 1620For example, to redirect host X11 connection from screen 1 to guest 1621screen 0, use the following: 1622 1623@example 1624# on the host 1625qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...] 1626# this host xterm should open in the guest X11 server 1627xterm -display :1 1628@end example 1629 1630To redirect telnet connections from host port 5555 to telnet port on 1631the guest, use the following: 1632 1633@example 1634# on the host 1635qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...] 1636telnet localhost 5555 1637@end example 1638 1639Then when you use on the host @code{telnet localhost 5555}, you 1640connect to the guest telnet server. 1641 1642@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev} 1643@item guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command} 1644Forward guest TCP connections to the IP address @var{server} on port @var{port} 1645to the character device @var{dev} or to a program executed by @var{cmd:command} 1646which gets spawned for each connection. This option can be given multiple times. 1647 1648You can either use a chardev directly and have that one used throughout QEMU's 1649lifetime, like in the following example: 1650 1651@example 1652# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever 1653# the guest accesses it 1654qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...] 1655@end example 1656 1657Or you can execute a command on every TCP connection established by the guest, 1658so that QEMU behaves similar to an inetd process for that virtual server: 1659 1660@example 1661# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 1662# and connect the TCP stream to its stdin/stdout 1663qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321' 1664@end example 1665 1666@end table 1667 1668Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still 1669processed and applied to -net user. Mixing them with the new configuration 1670syntax gives undefined results. Their use for new applications is discouraged 1671as they will be removed from future versions. 1672 1673@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}] 1674@item -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}] 1675Connect the host TAP network interface @var{name} to VLAN @var{n}. 1676 1677Use the network script @var{file} to configure it and the network script 1678@var{dfile} to deconfigure it. If @var{name} is not provided, the OS 1679automatically provides one. The default network configure script is 1680@file{/etc/qemu-ifup} and the default network deconfigure script is 1681@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no} 1682to disable script execution. 1683 1684If running QEMU as an unprivileged user, use the network helper 1685@var{helper} to configure the TAP interface. The default network 1686helper executable is @file{/path/to/qemu-bridge-helper}. 1687 1688@option{fd}=@var{h} can be used to specify the handle of an already 1689opened host TAP interface. 1690 1691Examples: 1692 1693@example 1694#launch a QEMU instance with the default network script 1695qemu-system-i386 linux.img -net nic -net tap 1696@end example 1697 1698@example 1699#launch a QEMU instance with two NICs, each one connected 1700#to a TAP device 1701qemu-system-i386 linux.img \ 1702 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \ 1703 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1 1704@end example 1705 1706@example 1707#launch a QEMU instance with the default network helper to 1708#connect a TAP device to bridge br0 1709qemu-system-i386 linux.img \ 1710 -net nic -net tap,"helper=/path/to/qemu-bridge-helper" 1711@end example 1712 1713@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}] 1714@item -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}] 1715Connect a host TAP network interface to a host bridge device. 1716 1717Use the network helper @var{helper} to configure the TAP interface and 1718attach it to the bridge. The default network helper executable is 1719@file{/path/to/qemu-bridge-helper} and the default bridge 1720device is @file{br0}. 1721 1722Examples: 1723 1724@example 1725#launch a QEMU instance with the default network helper to 1726#connect a TAP device to bridge br0 1727qemu-system-i386 linux.img -net bridge -net nic,model=virtio 1728@end example 1729 1730@example 1731#launch a QEMU instance with the default network helper to 1732#connect a TAP device to bridge qemubr0 1733qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio 1734@end example 1735 1736@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 1737@item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 1738 1739Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual 1740machine using a TCP socket connection. If @option{listen} is 1741specified, QEMU waits for incoming connections on @var{port} 1742(@var{host} is optional). @option{connect} is used to connect to 1743another QEMU instance using the @option{listen} option. @option{fd}=@var{h} 1744specifies an already opened TCP socket. 1745 1746Example: 1747@example 1748# launch a first QEMU instance 1749qemu-system-i386 linux.img \ 1750 -net nic,macaddr=52:54:00:12:34:56 \ 1751 -net socket,listen=:1234 1752# connect the VLAN 0 of this instance to the VLAN 0 1753# of the first instance 1754qemu-system-i386 linux.img \ 1755 -net nic,macaddr=52:54:00:12:34:57 \ 1756 -net socket,connect=127.0.0.1:1234 1757@end example 1758 1759@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 1760@item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 1761 1762Create a VLAN @var{n} shared with another QEMU virtual 1763machines using a UDP multicast socket, effectively making a bus for 1764every QEMU with same multicast address @var{maddr} and @var{port}. 1765NOTES: 1766@enumerate 1767@item 1768Several QEMU can be running on different hosts and share same bus (assuming 1769correct multicast setup for these hosts). 1770@item 1771mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see 1772@url{http://user-mode-linux.sf.net}. 1773@item 1774Use @option{fd=h} to specify an already opened UDP multicast socket. 1775@end enumerate 1776 1777Example: 1778@example 1779# launch one QEMU instance 1780qemu-system-i386 linux.img \ 1781 -net nic,macaddr=52:54:00:12:34:56 \ 1782 -net socket,mcast=230.0.0.1:1234 1783# launch another QEMU instance on same "bus" 1784qemu-system-i386 linux.img \ 1785 -net nic,macaddr=52:54:00:12:34:57 \ 1786 -net socket,mcast=230.0.0.1:1234 1787# launch yet another QEMU instance on same "bus" 1788qemu-system-i386 linux.img \ 1789 -net nic,macaddr=52:54:00:12:34:58 \ 1790 -net socket,mcast=230.0.0.1:1234 1791@end example 1792 1793Example (User Mode Linux compat.): 1794@example 1795# launch QEMU instance (note mcast address selected 1796# is UML's default) 1797qemu-system-i386 linux.img \ 1798 -net nic,macaddr=52:54:00:12:34:56 \ 1799 -net socket,mcast=239.192.168.1:1102 1800# launch UML 1801/path/to/linux ubd0=/path/to/root_fs eth0=mcast 1802@end example 1803 1804Example (send packets from host's 1.2.3.4): 1805@example 1806qemu-system-i386 linux.img \ 1807 -net nic,macaddr=52:54:00:12:34:56 \ 1808 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4 1809@end example 1810 1811@item -netdev l2tpv3,id=@var{id},src=@var{srcaddr},dst=@var{dstaddr}[,srcport=@var{srcport}][,dstport=@var{dstport}],txsession=@var{txsession}[,rxsession=@var{rxsession}][,ipv6][,udp][,cookie64][,counter][,pincounter][,txcookie=@var{txcookie}][,rxcookie=@var{rxcookie}][,offset=@var{offset}] 1812@item -net l2tpv3[,vlan=@var{n}][,name=@var{name}],src=@var{srcaddr},dst=@var{dstaddr}[,srcport=@var{srcport}][,dstport=@var{dstport}],txsession=@var{txsession}[,rxsession=@var{rxsession}][,ipv6][,udp][,cookie64][,counter][,pincounter][,txcookie=@var{txcookie}][,rxcookie=@var{rxcookie}][,offset=@var{offset}] 1813Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular 1814protocol to transport Ethernet (and other Layer 2) data frames between 1815two systems. It is present in routers, firewalls and the Linux kernel 1816(from version 3.3 onwards). 1817 1818This transport allows a VM to communicate to another VM, router or firewall directly. 1819 1820@item src=@var{srcaddr} 1821 source address (mandatory) 1822@item dst=@var{dstaddr} 1823 destination address (mandatory) 1824@item udp 1825 select udp encapsulation (default is ip). 1826@item srcport=@var{srcport} 1827 source udp port. 1828@item dstport=@var{dstport} 1829 destination udp port. 1830@item ipv6 1831 force v6, otherwise defaults to v4. 1832@item rxcookie=@var{rxcookie} 1833@item txcookie=@var{txcookie} 1834 Cookies are a weak form of security in the l2tpv3 specification. 1835Their function is mostly to prevent misconfiguration. By default they are 32 1836bit. 1837@item cookie64 1838 Set cookie size to 64 bit instead of the default 32 1839@item counter=off 1840 Force a 'cut-down' L2TPv3 with no counter as in 1841draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00 1842@item pincounter=on 1843 Work around broken counter handling in peer. This may also help on 1844networks which have packet reorder. 1845@item offset=@var{offset} 1846 Add an extra offset between header and data 1847 1848For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan 1849on the remote Linux host 1.2.3.4: 1850@example 1851# Setup tunnel on linux host using raw ip as encapsulation 1852# on 1.2.3.4 1853ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \ 1854 encap udp udp_sport 16384 udp_dport 16384 1855ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \ 1856 0xFFFFFFFF peer_session_id 0xFFFFFFFF 1857ifconfig vmtunnel0 mtu 1500 1858ifconfig vmtunnel0 up 1859brctl addif br-lan vmtunnel0 1860 1861 1862# on 4.3.2.1 1863# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter 1864 1865qemu-system-i386 linux.img -net nic -net l2tpv3,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter 1866 1867 1868@end example 1869 1870@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 1871@item -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 1872Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and 1873listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname} 1874and MODE @var{octalmode} to change default ownership and permissions for 1875communication port. This option is only available if QEMU has been compiled 1876with vde support enabled. 1877 1878Example: 1879@example 1880# launch vde switch 1881vde_switch -F -sock /tmp/myswitch 1882# launch QEMU instance 1883qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch 1884@end example 1885 1886@item -netdev hubport,id=@var{id},hubid=@var{hubid} 1887 1888Create a hub port on QEMU "vlan" @var{hubid}. 1889 1890The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single 1891netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the 1892required hub automatically. 1893 1894@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off] 1895 1896Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should 1897be a unix domain socket backed one. The vhost-user uses a specifically defined 1898protocol to pass vhost ioctl replacement messages to an application on the other 1899end of the socket. On non-MSIX guests, the feature can be forced with 1900@var{vhostforce}. 1901 1902Example: 1903@example 1904qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \ 1905 -numa node,memdev=mem \ 1906 -chardev socket,path=/path/to/socket \ 1907 -netdev type=vhost-user,id=net0,chardev=chr0 \ 1908 -device virtio-net-pci,netdev=net0 1909@end example 1910 1911@item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}] 1912Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default). 1913At most @var{len} bytes (64k by default) per packet are stored. The file format is 1914libpcap, so it can be analyzed with tools such as tcpdump or Wireshark. 1915 1916@item -net none 1917Indicate that no network devices should be configured. It is used to 1918override the default configuration (@option{-net nic -net user}) which 1919is activated if no @option{-net} options are provided. 1920ETEXI 1921 1922STEXI 1923@end table 1924ETEXI 1925DEFHEADING() 1926 1927DEFHEADING(Character device options:) 1928STEXI 1929 1930The general form of a character device option is: 1931@table @option 1932ETEXI 1933 1934DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, 1935 "-chardev null,id=id[,mux=on|off]\n" 1936 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n" 1937 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off] (tcp)\n" 1938 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off] (unix)\n" 1939 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" 1940 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n" 1941 "-chardev msmouse,id=id[,mux=on|off]\n" 1942 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n" 1943 " [,mux=on|off]\n" 1944 "-chardev ringbuf,id=id[,size=size]\n" 1945 "-chardev file,id=id,path=path[,mux=on|off]\n" 1946 "-chardev pipe,id=id,path=path[,mux=on|off]\n" 1947#ifdef _WIN32 1948 "-chardev console,id=id[,mux=on|off]\n" 1949 "-chardev serial,id=id,path=path[,mux=on|off]\n" 1950#else 1951 "-chardev pty,id=id[,mux=on|off]\n" 1952 "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n" 1953#endif 1954#ifdef CONFIG_BRLAPI 1955 "-chardev braille,id=id[,mux=on|off]\n" 1956#endif 1957#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 1958 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) 1959 "-chardev serial,id=id,path=path[,mux=on|off]\n" 1960 "-chardev tty,id=id,path=path[,mux=on|off]\n" 1961#endif 1962#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) 1963 "-chardev parallel,id=id,path=path[,mux=on|off]\n" 1964 "-chardev parport,id=id,path=path[,mux=on|off]\n" 1965#endif 1966#if defined(CONFIG_SPICE) 1967 "-chardev spicevmc,id=id,name=name[,debug=debug]\n" 1968 "-chardev spiceport,id=id,name=name[,debug=debug]\n" 1969#endif 1970 , QEMU_ARCH_ALL 1971) 1972 1973STEXI 1974@item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}] 1975@findex -chardev 1976Backend is one of: 1977@option{null}, 1978@option{socket}, 1979@option{udp}, 1980@option{msmouse}, 1981@option{vc}, 1982@option{ringbuf}, 1983@option{file}, 1984@option{pipe}, 1985@option{console}, 1986@option{serial}, 1987@option{pty}, 1988@option{stdio}, 1989@option{braille}, 1990@option{tty}, 1991@option{parallel}, 1992@option{parport}, 1993@option{spicevmc}. 1994@option{spiceport}. 1995The specific backend will determine the applicable options. 1996 1997All devices must have an id, which can be any string up to 127 characters long. 1998It is used to uniquely identify this device in other command line directives. 1999 2000A character device may be used in multiplexing mode by multiple front-ends. 2001The key sequence of @key{Control-a} and @key{c} will rotate the input focus 2002between attached front-ends. Specify @option{mux=on} to enable this mode. 2003 2004Options to each backend are described below. 2005 2006@item -chardev null ,id=@var{id} 2007A void device. This device will not emit any data, and will drop any data it 2008receives. The null backend does not take any options. 2009 2010@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}] 2011 2012Create a two-way stream socket, which can be either a TCP or a unix socket. A 2013unix socket will be created if @option{path} is specified. Behaviour is 2014undefined if TCP options are specified for a unix socket. 2015 2016@option{server} specifies that the socket shall be a listening socket. 2017 2018@option{nowait} specifies that QEMU should not block waiting for a client to 2019connect to a listening socket. 2020 2021@option{telnet} specifies that traffic on the socket should interpret telnet 2022escape sequences. 2023 2024@option{reconnect} sets the timeout for reconnecting on non-server sockets when 2025the remote end goes away. qemu will delay this many seconds and then attempt 2026to reconnect. Zero disables reconnecting, and is the default. 2027 2028TCP and unix socket options are given below: 2029 2030@table @option 2031 2032@item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay] 2033 2034@option{host} for a listening socket specifies the local address to be bound. 2035For a connecting socket species the remote host to connect to. @option{host} is 2036optional for listening sockets. If not specified it defaults to @code{0.0.0.0}. 2037 2038@option{port} for a listening socket specifies the local port to be bound. For a 2039connecting socket specifies the port on the remote host to connect to. 2040@option{port} can be given as either a port number or a service name. 2041@option{port} is required. 2042 2043@option{to} is only relevant to listening sockets. If it is specified, and 2044@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up 2045to and including @option{to} until it succeeds. @option{to} must be specified 2046as a port number. 2047 2048@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2049If neither is specified the socket may use either protocol. 2050 2051@option{nodelay} disables the Nagle algorithm. 2052 2053@item unix options: path=@var{path} 2054 2055@option{path} specifies the local path of the unix socket. @option{path} is 2056required. 2057 2058@end table 2059 2060@item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6] 2061 2062Sends all traffic from the guest to a remote host over UDP. 2063 2064@option{host} specifies the remote host to connect to. If not specified it 2065defaults to @code{localhost}. 2066 2067@option{port} specifies the port on the remote host to connect to. @option{port} 2068is required. 2069 2070@option{localaddr} specifies the local address to bind to. If not specified it 2071defaults to @code{0.0.0.0}. 2072 2073@option{localport} specifies the local port to bind to. If not specified any 2074available local port will be used. 2075 2076@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2077If neither is specified the device may use either protocol. 2078 2079@item -chardev msmouse ,id=@var{id} 2080 2081Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not 2082take any options. 2083 2084@item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]] 2085 2086Connect to a QEMU text console. @option{vc} may optionally be given a specific 2087size. 2088 2089@option{width} and @option{height} specify the width and height respectively of 2090the console, in pixels. 2091 2092@option{cols} and @option{rows} specify that the console be sized to fit a text 2093console with the given dimensions. 2094 2095@item -chardev ringbuf ,id=@var{id} [,size=@var{size}] 2096 2097Create a ring buffer with fixed size @option{size}. 2098@var{size} must be a power of two, and defaults to @code{64K}). 2099 2100@item -chardev file ,id=@var{id} ,path=@var{path} 2101 2102Log all traffic received from the guest to a file. 2103 2104@option{path} specifies the path of the file to be opened. This file will be 2105created if it does not already exist, and overwritten if it does. @option{path} 2106is required. 2107 2108@item -chardev pipe ,id=@var{id} ,path=@var{path} 2109 2110Create a two-way connection to the guest. The behaviour differs slightly between 2111Windows hosts and other hosts: 2112 2113On Windows, a single duplex pipe will be created at 2114@file{\\.pipe\@option{path}}. 2115 2116On other hosts, 2 pipes will be created called @file{@option{path}.in} and 2117@file{@option{path}.out}. Data written to @file{@option{path}.in} will be 2118received by the guest. Data written by the guest can be read from 2119@file{@option{path}.out}. QEMU will not create these fifos, and requires them to 2120be present. 2121 2122@option{path} forms part of the pipe path as described above. @option{path} is 2123required. 2124 2125@item -chardev console ,id=@var{id} 2126 2127Send traffic from the guest to QEMU's standard output. @option{console} does not 2128take any options. 2129 2130@option{console} is only available on Windows hosts. 2131 2132@item -chardev serial ,id=@var{id} ,path=@option{path} 2133 2134Send traffic from the guest to a serial device on the host. 2135 2136On Unix hosts serial will actually accept any tty device, 2137not only serial lines. 2138 2139@option{path} specifies the name of the serial device to open. 2140 2141@item -chardev pty ,id=@var{id} 2142 2143Create a new pseudo-terminal on the host and connect to it. @option{pty} does 2144not take any options. 2145 2146@option{pty} is not available on Windows hosts. 2147 2148@item -chardev stdio ,id=@var{id} [,signal=on|off] 2149Connect to standard input and standard output of the QEMU process. 2150 2151@option{signal} controls if signals are enabled on the terminal, that includes 2152exiting QEMU with the key sequence @key{Control-c}. This option is enabled by 2153default, use @option{signal=off} to disable it. 2154 2155@option{stdio} is not available on Windows hosts. 2156 2157@item -chardev braille ,id=@var{id} 2158 2159Connect to a local BrlAPI server. @option{braille} does not take any options. 2160 2161@item -chardev tty ,id=@var{id} ,path=@var{path} 2162 2163@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and 2164DragonFlyBSD hosts. It is an alias for @option{serial}. 2165 2166@option{path} specifies the path to the tty. @option{path} is required. 2167 2168@item -chardev parallel ,id=@var{id} ,path=@var{path} 2169@item -chardev parport ,id=@var{id} ,path=@var{path} 2170 2171@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts. 2172 2173Connect to a local parallel port. 2174 2175@option{path} specifies the path to the parallel port device. @option{path} is 2176required. 2177 2178@item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name} 2179 2180@option{spicevmc} is only available when spice support is built in. 2181 2182@option{debug} debug level for spicevmc 2183 2184@option{name} name of spice channel to connect to 2185 2186Connect to a spice virtual machine channel, such as vdiport. 2187 2188@item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name} 2189 2190@option{spiceport} is only available when spice support is built in. 2191 2192@option{debug} debug level for spicevmc 2193 2194@option{name} name of spice port to connect to 2195 2196Connect to a spice port, allowing a Spice client to handle the traffic 2197identified by a name (preferably a fqdn). 2198ETEXI 2199 2200STEXI 2201@end table 2202ETEXI 2203DEFHEADING() 2204 2205DEFHEADING(Device URL Syntax:) 2206STEXI 2207 2208In addition to using normal file images for the emulated storage devices, 2209QEMU can also use networked resources such as iSCSI devices. These are 2210specified using a special URL syntax. 2211 2212@table @option 2213@item iSCSI 2214iSCSI support allows QEMU to access iSCSI resources directly and use as 2215images for the guest storage. Both disk and cdrom images are supported. 2216 2217Syntax for specifying iSCSI LUNs is 2218``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>'' 2219 2220By default qemu will use the iSCSI initiator-name 2221'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command 2222line or a configuration file. 2223 2224 2225Example (without authentication): 2226@example 2227qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \ 2228 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \ 2229 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 2230@end example 2231 2232Example (CHAP username/password via URL): 2233@example 2234qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1 2235@end example 2236 2237Example (CHAP username/password via environment variables): 2238@example 2239LIBISCSI_CHAP_USERNAME="user" \ 2240LIBISCSI_CHAP_PASSWORD="password" \ 2241qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 2242@end example 2243 2244iSCSI support is an optional feature of QEMU and only available when 2245compiled and linked against libiscsi. 2246ETEXI 2247DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi, 2248 "-iscsi [user=user][,password=password]\n" 2249 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n" 2250 " [,initiator-name=initiator-iqn][,id=target-iqn]\n" 2251 " iSCSI session parameters\n", QEMU_ARCH_ALL) 2252STEXI 2253 2254iSCSI parameters such as username and password can also be specified via 2255a configuration file. See qemu-doc for more information and examples. 2256 2257@item NBD 2258QEMU supports NBD (Network Block Devices) both using TCP protocol as well 2259as Unix Domain Sockets. 2260 2261Syntax for specifying a NBD device using TCP 2262``nbd:<server-ip>:<port>[:exportname=<export>]'' 2263 2264Syntax for specifying a NBD device using Unix Domain Sockets 2265``nbd:unix:<domain-socket>[:exportname=<export>]'' 2266 2267 2268Example for TCP 2269@example 2270qemu-system-i386 --drive file=nbd:192.0.2.1:30000 2271@end example 2272 2273Example for Unix Domain Sockets 2274@example 2275qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket 2276@end example 2277 2278@item SSH 2279QEMU supports SSH (Secure Shell) access to remote disks. 2280 2281Examples: 2282@example 2283qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img 2284qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img 2285@end example 2286 2287Currently authentication must be done using ssh-agent. Other 2288authentication methods may be supported in future. 2289 2290@item Sheepdog 2291Sheepdog is a distributed storage system for QEMU. 2292QEMU supports using either local sheepdog devices or remote networked 2293devices. 2294 2295Syntax for specifying a sheepdog device 2296@example 2297sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag] 2298@end example 2299 2300Example 2301@example 2302qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine 2303@end example 2304 2305See also @url{http://http://www.osrg.net/sheepdog/}. 2306 2307@item GlusterFS 2308GlusterFS is an user space distributed file system. 2309QEMU supports the use of GlusterFS volumes for hosting VM disk images using 2310TCP, Unix Domain Sockets and RDMA transport protocols. 2311 2312Syntax for specifying a VM disk image on GlusterFS volume is 2313@example 2314gluster[+transport]://[server[:port]]/volname/image[?socket=...] 2315@end example 2316 2317 2318Example 2319@example 2320qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img 2321@end example 2322 2323See also @url{http://www.gluster.org}. 2324 2325@item HTTP/HTTPS/FTP/FTPS/TFTP 2326QEMU supports read-only access to files accessed over http(s), ftp(s) and tftp. 2327 2328Syntax using a single filename: 2329@example 2330<protocol>://[<username>[:<password>]@@]<host>/<path> 2331@end example 2332 2333where: 2334@table @option 2335@item protocol 2336'http', 'https', 'ftp', 'ftps', or 'tftp'. 2337 2338@item username 2339Optional username for authentication to the remote server. 2340 2341@item password 2342Optional password for authentication to the remote server. 2343 2344@item host 2345Address of the remote server. 2346 2347@item path 2348Path on the remote server, including any query string. 2349@end table 2350 2351The following options are also supported: 2352@table @option 2353@item url 2354The full URL when passing options to the driver explicitly. 2355 2356@item readahead 2357The amount of data to read ahead with each range request to the remote server. 2358This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it 2359does not have a suffix, it will be assumed to be in bytes. The value must be a 2360multiple of 512 bytes. It defaults to 256k. 2361 2362@item sslverify 2363Whether to verify the remote server's certificate when connecting over SSL. It 2364can have the value 'on' or 'off'. It defaults to 'on'. 2365 2366@item cookie 2367Send this cookie (it can also be a list of cookies separated by ';') with 2368each outgoing request. Only supported when using protocols such as HTTP 2369which support cookies, otherwise ignored. 2370 2371@item timeout 2372Set the timeout in seconds of the CURL connection. This timeout is the time 2373that CURL waits for a response from the remote server to get the size of the 2374image to be downloaded. If not set, the default timeout of 5 seconds is used. 2375@end table 2376 2377Note that when passing options to qemu explicitly, @option{driver} is the value 2378of <protocol>. 2379 2380Example: boot from a remote Fedora 20 live ISO image 2381@example 2382qemu-system-x86_64 --drive media=cdrom,file=http://dl.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly 2383 2384qemu-system-x86_64 --drive media=cdrom,file.driver=http,file.url=http://dl.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly 2385@end example 2386 2387Example: boot from a remote Fedora 20 cloud image using a local overlay for 2388writes, copy-on-read, and a readahead of 64k 2389@example 2390qemu-img create -f qcow2 -o backing_file='json:@{"file.driver":"http",, "file.url":"https://dl.fedoraproject.org/pub/fedora/linux/releases/20/Images/x86_64/Fedora-x86_64-20-20131211.1-sda.qcow2",, "file.readahead":"64k"@}' /tmp/Fedora-x86_64-20-20131211.1-sda.qcow2 2391 2392qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on 2393@end example 2394 2395Example: boot from an image stored on a VMware vSphere server with a self-signed 2396certificate using a local overlay for writes, a readahead of 64k and a timeout 2397of 10 seconds. 2398@example 2399qemu-img create -f qcow2 -o backing_file='json:@{"file.driver":"https",, "file.url":"https://user:password@@vsphere.example.com/folder/test/test-flat.vmdk?dcPath=Datacenter&dsName=datastore1",, "file.sslverify":"off",, "file.readahead":"64k",, "file.timeout":10@}' /tmp/test.qcow2 2400 2401qemu-system-x86_64 -drive file=/tmp/test.qcow2 2402@end example 2403ETEXI 2404 2405STEXI 2406@end table 2407ETEXI 2408 2409DEFHEADING(Bluetooth(R) options:) 2410STEXI 2411@table @option 2412ETEXI 2413 2414DEF("bt", HAS_ARG, QEMU_OPTION_bt, \ 2415 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \ 2416 "-bt hci,host[:id]\n" \ 2417 " use host's HCI with the given name\n" \ 2418 "-bt hci[,vlan=n]\n" \ 2419 " emulate a standard HCI in virtual scatternet 'n'\n" \ 2420 "-bt vhci[,vlan=n]\n" \ 2421 " add host computer to virtual scatternet 'n' using VHCI\n" \ 2422 "-bt device:dev[,vlan=n]\n" \ 2423 " emulate a bluetooth device 'dev' in scatternet 'n'\n", 2424 QEMU_ARCH_ALL) 2425STEXI 2426@item -bt hci[...] 2427@findex -bt 2428Defines the function of the corresponding Bluetooth HCI. -bt options 2429are matched with the HCIs present in the chosen machine type. For 2430example when emulating a machine with only one HCI built into it, only 2431the first @code{-bt hci[...]} option is valid and defines the HCI's 2432logic. The Transport Layer is decided by the machine type. Currently 2433the machines @code{n800} and @code{n810} have one HCI and all other 2434machines have none. 2435 2436@anchor{bt-hcis} 2437The following three types are recognized: 2438 2439@table @option 2440@item -bt hci,null 2441(default) The corresponding Bluetooth HCI assumes no internal logic 2442and will not respond to any HCI commands or emit events. 2443 2444@item -bt hci,host[:@var{id}] 2445(@code{bluez} only) The corresponding HCI passes commands / events 2446to / from the physical HCI identified by the name @var{id} (default: 2447@code{hci0}) on the computer running QEMU. Only available on @code{bluez} 2448capable systems like Linux. 2449 2450@item -bt hci[,vlan=@var{n}] 2451Add a virtual, standard HCI that will participate in the Bluetooth 2452scatternet @var{n} (default @code{0}). Similarly to @option{-net} 2453VLANs, devices inside a bluetooth network @var{n} can only communicate 2454with other devices in the same network (scatternet). 2455@end table 2456 2457@item -bt vhci[,vlan=@var{n}] 2458(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached 2459to the host bluetooth stack instead of to the emulated target. This 2460allows the host and target machines to participate in a common scatternet 2461and communicate. Requires the Linux @code{vhci} driver installed. Can 2462be used as following: 2463 2464@example 2465qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5 2466@end example 2467 2468@item -bt device:@var{dev}[,vlan=@var{n}] 2469Emulate a bluetooth device @var{dev} and place it in network @var{n} 2470(default @code{0}). QEMU can only emulate one type of bluetooth devices 2471currently: 2472 2473@table @option 2474@item keyboard 2475Virtual wireless keyboard implementing the HIDP bluetooth profile. 2476@end table 2477ETEXI 2478 2479STEXI 2480@end table 2481ETEXI 2482DEFHEADING() 2483 2484#ifdef CONFIG_TPM 2485DEFHEADING(TPM device options:) 2486 2487DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \ 2488 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n" 2489 " use path to provide path to a character device; default is /dev/tpm0\n" 2490 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n" 2491 " not provided it will be searched for in /sys/class/misc/tpm?/device\n", 2492 QEMU_ARCH_ALL) 2493STEXI 2494 2495The general form of a TPM device option is: 2496@table @option 2497 2498@item -tpmdev @var{backend} ,id=@var{id} [,@var{options}] 2499@findex -tpmdev 2500Backend type must be: 2501@option{passthrough}. 2502 2503The specific backend type will determine the applicable options. 2504The @code{-tpmdev} option creates the TPM backend and requires a 2505@code{-device} option that specifies the TPM frontend interface model. 2506 2507Options to each backend are described below. 2508 2509Use 'help' to print all available TPM backend types. 2510@example 2511qemu -tpmdev help 2512@end example 2513 2514@item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path} 2515 2516(Linux-host only) Enable access to the host's TPM using the passthrough 2517driver. 2518 2519@option{path} specifies the path to the host's TPM device, i.e., on 2520a Linux host this would be @code{/dev/tpm0}. 2521@option{path} is optional and by default @code{/dev/tpm0} is used. 2522 2523@option{cancel-path} specifies the path to the host TPM device's sysfs 2524entry allowing for cancellation of an ongoing TPM command. 2525@option{cancel-path} is optional and by default QEMU will search for the 2526sysfs entry to use. 2527 2528Some notes about using the host's TPM with the passthrough driver: 2529 2530The TPM device accessed by the passthrough driver must not be 2531used by any other application on the host. 2532 2533Since the host's firmware (BIOS/UEFI) has already initialized the TPM, 2534the VM's firmware (BIOS/UEFI) will not be able to initialize the 2535TPM again and may therefore not show a TPM-specific menu that would 2536otherwise allow the user to configure the TPM, e.g., allow the user to 2537enable/disable or activate/deactivate the TPM. 2538Further, if TPM ownership is released from within a VM then the host's TPM 2539will get disabled and deactivated. To enable and activate the 2540TPM again afterwards, the host has to be rebooted and the user is 2541required to enter the firmware's menu to enable and activate the TPM. 2542If the TPM is left disabled and/or deactivated most TPM commands will fail. 2543 2544To create a passthrough TPM use the following two options: 2545@example 2546-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0 2547@end example 2548Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by 2549@code{tpmdev=tpm0} in the device option. 2550 2551@end table 2552 2553ETEXI 2554 2555DEFHEADING() 2556 2557#endif 2558 2559DEFHEADING(Linux/Multiboot boot specific:) 2560STEXI 2561 2562When using these options, you can use a given Linux or Multiboot 2563kernel without installing it in the disk image. It can be useful 2564for easier testing of various kernels. 2565 2566@table @option 2567ETEXI 2568 2569DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \ 2570 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL) 2571STEXI 2572@item -kernel @var{bzImage} 2573@findex -kernel 2574Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel 2575or in multiboot format. 2576ETEXI 2577 2578DEF("append", HAS_ARG, QEMU_OPTION_append, \ 2579 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL) 2580STEXI 2581@item -append @var{cmdline} 2582@findex -append 2583Use @var{cmdline} as kernel command line 2584ETEXI 2585 2586DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \ 2587 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL) 2588STEXI 2589@item -initrd @var{file} 2590@findex -initrd 2591Use @var{file} as initial ram disk. 2592 2593@item -initrd "@var{file1} arg=foo,@var{file2}" 2594 2595This syntax is only available with multiboot. 2596 2597Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the 2598first module. 2599ETEXI 2600 2601DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \ 2602 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL) 2603STEXI 2604@item -dtb @var{file} 2605@findex -dtb 2606Use @var{file} as a device tree binary (dtb) image and pass it to the kernel 2607on boot. 2608ETEXI 2609 2610STEXI 2611@end table 2612ETEXI 2613DEFHEADING() 2614 2615DEFHEADING(Debug/Expert options:) 2616STEXI 2617@table @option 2618ETEXI 2619 2620DEF("serial", HAS_ARG, QEMU_OPTION_serial, \ 2621 "-serial dev redirect the serial port to char device 'dev'\n", 2622 QEMU_ARCH_ALL) 2623STEXI 2624@item -serial @var{dev} 2625@findex -serial 2626Redirect the virtual serial port to host character device 2627@var{dev}. The default device is @code{vc} in graphical mode and 2628@code{stdio} in non graphical mode. 2629 2630This option can be used several times to simulate up to 4 serial 2631ports. 2632 2633Use @code{-serial none} to disable all serial ports. 2634 2635Available character devices are: 2636@table @option 2637@item vc[:@var{W}x@var{H}] 2638Virtual console. Optionally, a width and height can be given in pixel with 2639@example 2640vc:800x600 2641@end example 2642It is also possible to specify width or height in characters: 2643@example 2644vc:80Cx24C 2645@end example 2646@item pty 2647[Linux only] Pseudo TTY (a new PTY is automatically allocated) 2648@item none 2649No device is allocated. 2650@item null 2651void device 2652@item chardev:@var{id} 2653Use a named character device defined with the @code{-chardev} option. 2654@item /dev/XXX 2655[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port 2656parameters are set according to the emulated ones. 2657@item /dev/parport@var{N} 2658[Linux only, parallel port only] Use host parallel port 2659@var{N}. Currently SPP and EPP parallel port features can be used. 2660@item file:@var{filename} 2661Write output to @var{filename}. No character can be read. 2662@item stdio 2663[Unix only] standard input/output 2664@item pipe:@var{filename} 2665name pipe @var{filename} 2666@item COM@var{n} 2667[Windows only] Use host serial port @var{n} 2668@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}] 2669This implements UDP Net Console. 2670When @var{remote_host} or @var{src_ip} are not specified 2671they default to @code{0.0.0.0}. 2672When not using a specified @var{src_port} a random port is automatically chosen. 2673 2674If you just want a simple readonly console you can use @code{netcat} or 2675@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as: 2676@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it 2677will appear in the netconsole session. 2678 2679If you plan to send characters back via netconsole or you want to stop 2680and start QEMU a lot of times, you should have QEMU use the same 2681source port each time by using something like @code{-serial 2682udp::4555@@:4556} to QEMU. Another approach is to use a patched 2683version of netcat which can listen to a TCP port and send and receive 2684characters via udp. If you have a patched version of netcat which 2685activates telnet remote echo and single char transfer, then you can 2686use the following options to step up a netcat redirector to allow 2687telnet on port 5555 to access the QEMU port. 2688@table @code 2689@item QEMU Options: 2690-serial udp::4555@@:4556 2691@item netcat options: 2692-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T 2693@item telnet options: 2694localhost 5555 2695@end table 2696 2697@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}] 2698The TCP Net Console has two modes of operation. It can send the serial 2699I/O to a location or wait for a connection from a location. By default 2700the TCP Net Console is sent to @var{host} at the @var{port}. If you use 2701the @var{server} option QEMU will wait for a client socket application 2702to connect to the port before continuing, unless the @code{nowait} 2703option was specified. The @code{nodelay} option disables the Nagle buffering 2704algorithm. The @code{reconnect} option only applies if @var{noserver} is 2705set, if the connection goes down it will attempt to reconnect at the 2706given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only 2707one TCP connection at a time is accepted. You can use @code{telnet} to 2708connect to the corresponding character device. 2709@table @code 2710@item Example to send tcp console to 192.168.0.2 port 4444 2711-serial tcp:192.168.0.2:4444 2712@item Example to listen and wait on port 4444 for connection 2713-serial tcp::4444,server 2714@item Example to not wait and listen on ip 192.168.0.100 port 4444 2715-serial tcp:192.168.0.100:4444,server,nowait 2716@end table 2717 2718@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay] 2719The telnet protocol is used instead of raw tcp sockets. The options 2720work the same as if you had specified @code{-serial tcp}. The 2721difference is that the port acts like a telnet server or client using 2722telnet option negotiation. This will also allow you to send the 2723MAGIC_SYSRQ sequence if you use a telnet that supports sending the break 2724sequence. Typically in unix telnet you do it with Control-] and then 2725type "send break" followed by pressing the enter key. 2726 2727@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}] 2728A unix domain socket is used instead of a tcp socket. The option works the 2729same as if you had specified @code{-serial tcp} except the unix domain socket 2730@var{path} is used for connections. 2731 2732@item mon:@var{dev_string} 2733This is a special option to allow the monitor to be multiplexed onto 2734another serial port. The monitor is accessed with key sequence of 2735@key{Control-a} and then pressing @key{c}. 2736@var{dev_string} should be any one of the serial devices specified 2737above. An example to multiplex the monitor onto a telnet server 2738listening on port 4444 would be: 2739@table @code 2740@item -serial mon:telnet::4444,server,nowait 2741@end table 2742When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate 2743QEMU any more but will be passed to the guest instead. 2744 2745@item braille 2746Braille device. This will use BrlAPI to display the braille output on a real 2747or fake device. 2748 2749@item msmouse 2750Three button serial mouse. Configure the guest to use Microsoft protocol. 2751@end table 2752ETEXI 2753 2754DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \ 2755 "-parallel dev redirect the parallel port to char device 'dev'\n", 2756 QEMU_ARCH_ALL) 2757STEXI 2758@item -parallel @var{dev} 2759@findex -parallel 2760Redirect the virtual parallel port to host device @var{dev} (same 2761devices as the serial port). On Linux hosts, @file{/dev/parportN} can 2762be used to use hardware devices connected on the corresponding host 2763parallel port. 2764 2765This option can be used several times to simulate up to 3 parallel 2766ports. 2767 2768Use @code{-parallel none} to disable all parallel ports. 2769ETEXI 2770 2771DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \ 2772 "-monitor dev redirect the monitor to char device 'dev'\n", 2773 QEMU_ARCH_ALL) 2774STEXI 2775@item -monitor @var{dev} 2776@findex -monitor 2777Redirect the monitor to host device @var{dev} (same devices as the 2778serial port). 2779The default device is @code{vc} in graphical mode and @code{stdio} in 2780non graphical mode. 2781Use @code{-monitor none} to disable the default monitor. 2782ETEXI 2783DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \ 2784 "-qmp dev like -monitor but opens in 'control' mode\n", 2785 QEMU_ARCH_ALL) 2786STEXI 2787@item -qmp @var{dev} 2788@findex -qmp 2789Like -monitor but opens in 'control' mode. 2790ETEXI 2791 2792DEF("mon", HAS_ARG, QEMU_OPTION_mon, \ 2793 "-mon [chardev=]name[,mode=readline|control][,default]\n", QEMU_ARCH_ALL) 2794STEXI 2795@item -mon [chardev=]name[,mode=readline|control][,default] 2796@findex -mon 2797Setup monitor on chardev @var{name}. 2798ETEXI 2799 2800DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ 2801 "-debugcon dev redirect the debug console to char device 'dev'\n", 2802 QEMU_ARCH_ALL) 2803STEXI 2804@item -debugcon @var{dev} 2805@findex -debugcon 2806Redirect the debug console to host device @var{dev} (same devices as the 2807serial port). The debug console is an I/O port which is typically port 28080xe9; writing to that I/O port sends output to this device. 2809The default device is @code{vc} in graphical mode and @code{stdio} in 2810non graphical mode. 2811ETEXI 2812 2813DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ 2814 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL) 2815STEXI 2816@item -pidfile @var{file} 2817@findex -pidfile 2818Store the QEMU process PID in @var{file}. It is useful if you launch QEMU 2819from a script. 2820ETEXI 2821 2822DEF("singlestep", 0, QEMU_OPTION_singlestep, \ 2823 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) 2824STEXI 2825@item -singlestep 2826@findex -singlestep 2827Run the emulation in single step mode. 2828ETEXI 2829 2830DEF("S", 0, QEMU_OPTION_S, \ 2831 "-S freeze CPU at startup (use 'c' to start execution)\n", 2832 QEMU_ARCH_ALL) 2833STEXI 2834@item -S 2835@findex -S 2836Do not start CPU at startup (you must type 'c' in the monitor). 2837ETEXI 2838 2839DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, 2840 "-realtime [mlock=on|off]\n" 2841 " run qemu with realtime features\n" 2842 " mlock=on|off controls mlock support (default: on)\n", 2843 QEMU_ARCH_ALL) 2844STEXI 2845@item -realtime mlock=on|off 2846@findex -realtime 2847Run qemu with realtime features. 2848mlocking qemu and guest memory can be enabled via @option{mlock=on} 2849(enabled by default). 2850ETEXI 2851 2852DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ 2853 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) 2854STEXI 2855@item -gdb @var{dev} 2856@findex -gdb 2857Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical 2858connections will likely be TCP-based, but also UDP, pseudo TTY, or even 2859stdio are reasonable use case. The latter is allowing to start QEMU from 2860within gdb and establish the connection via a pipe: 2861@example 2862(gdb) target remote | exec qemu-system-i386 -gdb stdio ... 2863@end example 2864ETEXI 2865 2866DEF("s", 0, QEMU_OPTION_s, \ 2867 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n", 2868 QEMU_ARCH_ALL) 2869STEXI 2870@item -s 2871@findex -s 2872Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234 2873(@pxref{gdb_usage}). 2874ETEXI 2875 2876DEF("d", HAS_ARG, QEMU_OPTION_d, \ 2877 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n", 2878 QEMU_ARCH_ALL) 2879STEXI 2880@item -d @var{item1}[,...] 2881@findex -d 2882Enable logging of specified items. Use '-d help' for a list of log items. 2883ETEXI 2884 2885DEF("D", HAS_ARG, QEMU_OPTION_D, \ 2886 "-D logfile output log to logfile (default stderr)\n", 2887 QEMU_ARCH_ALL) 2888STEXI 2889@item -D @var{logfile} 2890@findex -D 2891Output log in @var{logfile} instead of to stderr 2892ETEXI 2893 2894DEF("L", HAS_ARG, QEMU_OPTION_L, \ 2895 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", 2896 QEMU_ARCH_ALL) 2897STEXI 2898@item -L @var{path} 2899@findex -L 2900Set the directory for the BIOS, VGA BIOS and keymaps. 2901ETEXI 2902 2903DEF("bios", HAS_ARG, QEMU_OPTION_bios, \ 2904 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL) 2905STEXI 2906@item -bios @var{file} 2907@findex -bios 2908Set the filename for the BIOS. 2909ETEXI 2910 2911DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \ 2912 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL) 2913STEXI 2914@item -enable-kvm 2915@findex -enable-kvm 2916Enable KVM full virtualization support. This option is only available 2917if KVM support is enabled when compiling. 2918ETEXI 2919 2920DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, 2921 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) 2922DEF("xen-create", 0, QEMU_OPTION_xen_create, 2923 "-xen-create create domain using xen hypercalls, bypassing xend\n" 2924 " warning: should not be used when xend is in use\n", 2925 QEMU_ARCH_ALL) 2926DEF("xen-attach", 0, QEMU_OPTION_xen_attach, 2927 "-xen-attach attach to existing xen domain\n" 2928 " xend will use this when starting QEMU\n", 2929 QEMU_ARCH_ALL) 2930STEXI 2931@item -xen-domid @var{id} 2932@findex -xen-domid 2933Specify xen guest domain @var{id} (XEN only). 2934@item -xen-create 2935@findex -xen-create 2936Create domain using xen hypercalls, bypassing xend. 2937Warning: should not be used when xend is in use (XEN only). 2938@item -xen-attach 2939@findex -xen-attach 2940Attach to existing xen domain. 2941xend will use this when starting QEMU (XEN only). 2942ETEXI 2943 2944DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \ 2945 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL) 2946STEXI 2947@item -no-reboot 2948@findex -no-reboot 2949Exit instead of rebooting. 2950ETEXI 2951 2952DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \ 2953 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL) 2954STEXI 2955@item -no-shutdown 2956@findex -no-shutdown 2957Don't exit QEMU on guest shutdown, but instead only stop the emulation. 2958This allows for instance switching to monitor to commit changes to the 2959disk image. 2960ETEXI 2961 2962DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ 2963 "-loadvm [tag|id]\n" \ 2964 " start right away with a saved state (loadvm in monitor)\n", 2965 QEMU_ARCH_ALL) 2966STEXI 2967@item -loadvm @var{file} 2968@findex -loadvm 2969Start right away with a saved state (@code{loadvm} in monitor) 2970ETEXI 2971 2972#ifndef _WIN32 2973DEF("daemonize", 0, QEMU_OPTION_daemonize, \ 2974 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) 2975#endif 2976STEXI 2977@item -daemonize 2978@findex -daemonize 2979Daemonize the QEMU process after initialization. QEMU will not detach from 2980standard IO until it is ready to receive connections on any of its devices. 2981This option is a useful way for external programs to launch QEMU without having 2982to cope with initialization race conditions. 2983ETEXI 2984 2985DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \ 2986 "-option-rom rom load a file, rom, into the option ROM space\n", 2987 QEMU_ARCH_ALL) 2988STEXI 2989@item -option-rom @var{file} 2990@findex -option-rom 2991Load the contents of @var{file} as an option ROM. 2992This option is useful to load things like EtherBoot. 2993ETEXI 2994 2995HXCOMM Silently ignored for compatibility 2996DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL) 2997 2998HXCOMM Options deprecated by -rtc 2999DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL) 3000DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL) 3001 3002DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \ 3003 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \ 3004 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n", 3005 QEMU_ARCH_ALL) 3006 3007STEXI 3008 3009@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew] 3010@findex -rtc 3011Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current 3012UTC or local time, respectively. @code{localtime} is required for correct date in 3013MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the 3014format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC. 3015 3016By default the RTC is driven by the host system time. This allows using of the 3017RTC as accurate reference clock inside the guest, specifically if the host 3018time is smoothly following an accurate external reference clock, e.g. via NTP. 3019If you want to isolate the guest time from the host, you can set @option{clock} 3020to @code{rt} instead. To even prevent it from progressing during suspension, 3021you can set it to @code{vm}. 3022 3023Enable @option{driftfix} (i386 targets only) if you experience time drift problems, 3024specifically with Windows' ACPI HAL. This option will try to figure out how 3025many timer interrupts were not processed by the Windows guest and will 3026re-inject them. 3027ETEXI 3028 3029DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ 3030 "-icount [shift=N|auto][,align=on|off]\n" \ 3031 " enable virtual instruction counter with 2^N clock ticks per\n" \ 3032 " instruction and enable aligning the host and virtual clocks\n", QEMU_ARCH_ALL) 3033STEXI 3034@item -icount [shift=@var{N}|auto] 3035@findex -icount 3036Enable virtual instruction counter. The virtual cpu will execute one 3037instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified 3038then the virtual cpu speed will be automatically adjusted to keep virtual 3039time within a few seconds of real time. 3040 3041Note that while this option can give deterministic behavior, it does not 3042provide cycle accurate emulation. Modern CPUs contain superscalar out of 3043order cores with complex cache hierarchies. The number of instructions 3044executed often has little or no correlation with actual performance. 3045 3046@option{align=on} will activate the delay algorithm which will try to 3047to synchronise the host clock and the virtual clock. The goal is to 3048have a guest running at the real frequency imposed by the shift option. 3049Whenever the guest clock is behind the host clock and if 3050@option{align=on} is specified then we print a messsage to the user 3051to inform about the delay. 3052Currently this option does not work when @option{shift} is @code{auto}. 3053Note: The sync algorithm will work for those shift values for which 3054the guest clock runs ahead of the host clock. Typically this happens 3055when the shift value is high (how high depends on the host machine). 3056ETEXI 3057 3058DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ 3059 "-watchdog i6300esb|ib700\n" \ 3060 " enable virtual hardware watchdog [default=none]\n", 3061 QEMU_ARCH_ALL) 3062STEXI 3063@item -watchdog @var{model} 3064@findex -watchdog 3065Create a virtual hardware watchdog device. Once enabled (by a guest 3066action), the watchdog must be periodically polled by an agent inside 3067the guest or else the guest will be restarted. 3068 3069The @var{model} is the model of hardware watchdog to emulate. Choices 3070for model are: @code{ib700} (iBASE 700) which is a very simple ISA 3071watchdog with a single timer, or @code{i6300esb} (Intel 6300ESB I/O 3072controller hub) which is a much more featureful PCI-based dual-timer 3073watchdog. Choose a model for which your guest has drivers. 3074 3075Use @code{-watchdog help} to list available hardware models. Only one 3076watchdog can be enabled for a guest. 3077ETEXI 3078 3079DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \ 3080 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \ 3081 " action when watchdog fires [default=reset]\n", 3082 QEMU_ARCH_ALL) 3083STEXI 3084@item -watchdog-action @var{action} 3085@findex -watchdog-action 3086 3087The @var{action} controls what QEMU will do when the watchdog timer 3088expires. 3089The default is 3090@code{reset} (forcefully reset the guest). 3091Other possible actions are: 3092@code{shutdown} (attempt to gracefully shutdown the guest), 3093@code{poweroff} (forcefully poweroff the guest), 3094@code{pause} (pause the guest), 3095@code{debug} (print a debug message and continue), or 3096@code{none} (do nothing). 3097 3098Note that the @code{shutdown} action requires that the guest responds 3099to ACPI signals, which it may not be able to do in the sort of 3100situations where the watchdog would have expired, and thus 3101@code{-watchdog-action shutdown} is not recommended for production use. 3102 3103Examples: 3104 3105@table @code 3106@item -watchdog i6300esb -watchdog-action pause 3107@item -watchdog ib700 3108@end table 3109ETEXI 3110 3111DEF("echr", HAS_ARG, QEMU_OPTION_echr, \ 3112 "-echr chr set terminal escape character instead of ctrl-a\n", 3113 QEMU_ARCH_ALL) 3114STEXI 3115 3116@item -echr @var{numeric_ascii_value} 3117@findex -echr 3118Change the escape character used for switching to the monitor when using 3119monitor and serial sharing. The default is @code{0x01} when using the 3120@code{-nographic} option. @code{0x01} is equal to pressing 3121@code{Control-a}. You can select a different character from the ascii 3122control keys where 1 through 26 map to Control-a through Control-z. For 3123instance you could use the either of the following to change the escape 3124character to Control-t. 3125@table @code 3126@item -echr 0x14 3127@item -echr 20 3128@end table 3129ETEXI 3130 3131DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \ 3132 "-virtioconsole c\n" \ 3133 " set virtio console\n", QEMU_ARCH_ALL) 3134STEXI 3135@item -virtioconsole @var{c} 3136@findex -virtioconsole 3137Set virtio console. 3138 3139This option is maintained for backward compatibility. 3140 3141Please use @code{-device virtconsole} for the new way of invocation. 3142ETEXI 3143 3144DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \ 3145 "-show-cursor show cursor\n", QEMU_ARCH_ALL) 3146STEXI 3147@item -show-cursor 3148@findex -show-cursor 3149Show cursor. 3150ETEXI 3151 3152DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \ 3153 "-tb-size n set TB size\n", QEMU_ARCH_ALL) 3154STEXI 3155@item -tb-size @var{n} 3156@findex -tb-size 3157Set TB size. 3158ETEXI 3159 3160DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \ 3161 "-incoming p prepare for incoming migration, listen on port p\n", 3162 QEMU_ARCH_ALL) 3163STEXI 3164@item -incoming @var{port} 3165@findex -incoming 3166Prepare for incoming migration, listen on @var{port}. 3167ETEXI 3168 3169DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \ 3170 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL) 3171STEXI 3172@item -nodefaults 3173@findex -nodefaults 3174Don't create default devices. Normally, QEMU sets the default devices like serial 3175port, parallel port, virtual console, monitor device, VGA adapter, floppy and 3176CD-ROM drive and others. The @code{-nodefaults} option will disable all those 3177default devices. 3178ETEXI 3179 3180#ifndef _WIN32 3181DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \ 3182 "-chroot dir chroot to dir just before starting the VM\n", 3183 QEMU_ARCH_ALL) 3184#endif 3185STEXI 3186@item -chroot @var{dir} 3187@findex -chroot 3188Immediately before starting guest execution, chroot to the specified 3189directory. Especially useful in combination with -runas. 3190ETEXI 3191 3192#ifndef _WIN32 3193DEF("runas", HAS_ARG, QEMU_OPTION_runas, \ 3194 "-runas user change to user id user just before starting the VM\n", 3195 QEMU_ARCH_ALL) 3196#endif 3197STEXI 3198@item -runas @var{user} 3199@findex -runas 3200Immediately before starting guest execution, drop root privileges, switching 3201to the specified user. 3202ETEXI 3203 3204DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env, 3205 "-prom-env variable=value\n" 3206 " set OpenBIOS nvram variables\n", 3207 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 3208STEXI 3209@item -prom-env @var{variable}=@var{value} 3210@findex -prom-env 3211Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only). 3212ETEXI 3213DEF("semihosting", 0, QEMU_OPTION_semihosting, 3214 "-semihosting semihosting mode\n", 3215 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32) 3216STEXI 3217@item -semihosting 3218@findex -semihosting 3219Semihosting mode (ARM, M68K, Xtensa only). 3220ETEXI 3221DEF("old-param", 0, QEMU_OPTION_old_param, 3222 "-old-param old param mode\n", QEMU_ARCH_ARM) 3223STEXI 3224@item -old-param 3225@findex -old-param (ARM) 3226Old param mode (ARM only). 3227ETEXI 3228 3229DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ 3230 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n", 3231 QEMU_ARCH_ALL) 3232STEXI 3233@item -sandbox @var{arg} 3234@findex -sandbox 3235Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will 3236disable it. The default is 'off'. 3237ETEXI 3238 3239DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, 3240 "-readconfig <file>\n", QEMU_ARCH_ALL) 3241STEXI 3242@item -readconfig @var{file} 3243@findex -readconfig 3244Read device configuration from @var{file}. This approach is useful when you want to spawn 3245QEMU process with many command line options but you don't want to exceed the command line 3246character limit. 3247ETEXI 3248DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig, 3249 "-writeconfig <file>\n" 3250 " read/write config file\n", QEMU_ARCH_ALL) 3251STEXI 3252@item -writeconfig @var{file} 3253@findex -writeconfig 3254Write device configuration to @var{file}. The @var{file} can be either filename to save 3255command line and device configuration into file or dash @code{-}) character to print the 3256output to stdout. This can be later used as input file for @code{-readconfig} option. 3257ETEXI 3258DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, 3259 "-nodefconfig\n" 3260 " do not load default config files at startup\n", 3261 QEMU_ARCH_ALL) 3262STEXI 3263@item -nodefconfig 3264@findex -nodefconfig 3265Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup. 3266The @code{-nodefconfig} option will prevent QEMU from loading any of those config files. 3267ETEXI 3268DEF("no-user-config", 0, QEMU_OPTION_nouserconfig, 3269 "-no-user-config\n" 3270 " do not load user-provided config files at startup\n", 3271 QEMU_ARCH_ALL) 3272STEXI 3273@item -no-user-config 3274@findex -no-user-config 3275The @code{-no-user-config} option makes QEMU not load any of the user-provided 3276config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config 3277files from @var{datadir}. 3278ETEXI 3279DEF("trace", HAS_ARG, QEMU_OPTION_trace, 3280 "-trace [events=<file>][,file=<file>]\n" 3281 " specify tracing options\n", 3282 QEMU_ARCH_ALL) 3283STEXI 3284HXCOMM This line is not accurate, as some sub-options are backend-specific but 3285HXCOMM HX does not support conditional compilation of text. 3286@item -trace [events=@var{file}][,file=@var{file}] 3287@findex -trace 3288 3289Specify tracing options. 3290 3291@table @option 3292@item events=@var{file} 3293Immediately enable events listed in @var{file}. 3294The file must contain one event name (as listed in the @var{trace-events} file) 3295per line. 3296This option is only available if QEMU has been compiled with 3297either @var{simple} or @var{stderr} tracing backend. 3298@item file=@var{file} 3299Log output traces to @var{file}. 3300 3301This option is only available if QEMU has been compiled with 3302the @var{simple} tracing backend. 3303@end table 3304ETEXI 3305 3306HXCOMM Internal use 3307DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL) 3308DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL) 3309 3310#ifdef __linux__ 3311DEF("enable-fips", 0, QEMU_OPTION_enablefips, 3312 "-enable-fips enable FIPS 140-2 compliance\n", 3313 QEMU_ARCH_ALL) 3314#endif 3315STEXI 3316@item -enable-fips 3317@findex -enable-fips 3318Enable FIPS 140-2 compliance mode. 3319ETEXI 3320 3321HXCOMM Deprecated by -machine accel=tcg property 3322DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386) 3323 3324HXCOMM Deprecated by kvm-pit driver properties 3325DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection, 3326 "", QEMU_ARCH_I386) 3327 3328HXCOMM Deprecated (ignored) 3329DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386) 3330 3331HXCOMM Deprecated by -machine kernel_irqchip=on|off property 3332DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386) 3333 3334HXCOMM Deprecated (ignored) 3335DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL) 3336 3337DEF("object", HAS_ARG, QEMU_OPTION_object, 3338 "-object TYPENAME[,PROP1=VALUE1,...]\n" 3339 " create an new object of type TYPENAME setting properties\n" 3340 " in the order they are specified. Note that the 'id'\n" 3341 " property must be set. These objects are placed in the\n" 3342 " '/objects' path.\n", 3343 QEMU_ARCH_ALL) 3344STEXI 3345@item -object @var{typename}[,@var{prop1}=@var{value1},...] 3346@findex -object 3347Create an new object of type @var{typename} setting properties 3348in the order they are specified. Note that the 'id' 3349property must be set. These objects are placed in the 3350'/objects' path. 3351ETEXI 3352 3353DEF("msg", HAS_ARG, QEMU_OPTION_msg, 3354 "-msg timestamp[=on|off]\n" 3355 " change the format of messages\n" 3356 " on|off controls leading timestamps (default:on)\n", 3357 QEMU_ARCH_ALL) 3358STEXI 3359@item -msg timestamp[=on|off] 3360@findex -msg 3361prepend a timestamp to each log message.(default:on) 3362ETEXI 3363 3364DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate, 3365 "-dump-vmstate <file>\n" 3366 " Output vmstate information in JSON format to file.\n" 3367 " Use the scripts/vmstate-static-checker.py file to\n" 3368 " check for possible regressions in migration code\n" 3369 " by comparing two such vmstate dumps.", 3370 QEMU_ARCH_ALL) 3371STEXI 3372@item -dump-vmstate @var{file} 3373@findex -dump-vmstate 3374Dump json-encoded vmstate information for current machine type to file 3375in @var{file} 3376ETEXI 3377 3378HXCOMM This is the last statement. Insert new options before this line! 3379STEXI 3380@end table 3381ETEXI 3382
