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|auto controls emulation of vmport (default: auto)\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 " aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n" 42 " dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n" 43 " suppress-vmdesc=on|off disables self-describing migration (default=off)\n", 44 QEMU_ARCH_ALL) 45STEXI 46@item -machine [type=]@var{name}[,prop=@var{value}[,...]] 47@findex -machine 48Select the emulated machine by @var{name}. Use @code{-machine help} to list 49available machines. Supported machine properties are: 50@table @option 51@item accel=@var{accels1}[:@var{accels2}[:...]] 52This is used to enable an accelerator. Depending on the target architecture, 53kvm, xen, or tcg can be available. By default, tcg is used. If there is more 54than one accelerator specified, the next one is used if the previous one fails 55to initialize. 56@item kernel_irqchip=on|off 57Enables in-kernel irqchip support for the chosen accelerator when available. 58@item vmport=on|off|auto 59Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the 60value based on accel. For accel=xen the default is off otherwise the default 61is on. 62@item kvm_shadow_mem=size 63Defines the size of the KVM shadow MMU. 64@item dump-guest-core=on|off 65Include guest memory in a core dump. The default is on. 66@item mem-merge=on|off 67Enables or disables memory merge support. This feature, when supported by 68the host, de-duplicates identical memory pages among VMs instances 69(enabled by default). 70@item iommu=on|off 71Enables or disables emulated Intel IOMMU (VT-d) support. The default is off. 72@item aes-key-wrap=on|off 73Enables or disables AES key wrapping support on s390-ccw hosts. This feature 74controls whether AES wrapping keys will be created to allow 75execution of AES cryptographic functions. The default is on. 76@item dea-key-wrap=on|off 77Enables or disables DEA key wrapping support on s390-ccw hosts. This feature 78controls whether DEA wrapping keys will be created to allow 79execution of DEA cryptographic functions. The default is on. 80@end table 81ETEXI 82 83HXCOMM Deprecated by -machine 84DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL) 85 86DEF("cpu", HAS_ARG, QEMU_OPTION_cpu, 87 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL) 88STEXI 89@item -cpu @var{model} 90@findex -cpu 91Select CPU model (@code{-cpu help} for list and additional feature selection) 92ETEXI 93 94DEF("smp", HAS_ARG, QEMU_OPTION_smp, 95 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n" 96 " set the number of CPUs to 'n' [default=1]\n" 97 " maxcpus= maximum number of total cpus, including\n" 98 " offline CPUs for hotplug, etc\n" 99 " cores= number of CPU cores on one socket\n" 100 " threads= number of threads on one CPU core\n" 101 " sockets= number of discrete sockets in the system\n", 102 QEMU_ARCH_ALL) 103STEXI 104@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}] 105@findex -smp 106Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255 107CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs 108to 4. 109For the PC target, the number of @var{cores} per socket, the number 110of @var{threads} per cores and the total number of @var{sockets} can be 111specified. Missing values will be computed. If any on the three values is 112given, the total number of CPUs @var{n} can be omitted. @var{maxcpus} 113specifies the maximum number of hotpluggable CPUs. 114ETEXI 115 116DEF("numa", HAS_ARG, QEMU_OPTION_numa, 117 "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n" 118 "-numa node[,memdev=id][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL) 119STEXI 120@item -numa node[,mem=@var{size}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}] 121@item -numa node[,memdev=@var{id}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}] 122@findex -numa 123Simulate a multi node NUMA system. If @samp{mem}, @samp{memdev} 124and @samp{cpus} are omitted, resources are split equally. Also, note 125that the -@option{numa} option doesn't allocate any of the specified 126resources. That is, it just assigns existing resources to NUMA nodes. This 127means that one still has to use the @option{-m}, @option{-smp} options 128to allocate RAM and VCPUs respectively, and possibly @option{-object} 129to specify the memory backend for the @samp{memdev} suboption. 130 131@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, if one 132node uses @samp{memdev}, all of them have to use it. 133ETEXI 134 135DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd, 136 "-add-fd fd=fd,set=set[,opaque=opaque]\n" 137 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL) 138STEXI 139@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}] 140@findex -add-fd 141 142Add a file descriptor to an fd set. Valid options are: 143 144@table @option 145@item fd=@var{fd} 146This option defines the file descriptor of which a duplicate is added to fd set. 147The file descriptor cannot be stdin, stdout, or stderr. 148@item set=@var{set} 149This option defines the ID of the fd set to add the file descriptor to. 150@item opaque=@var{opaque} 151This option defines a free-form string that can be used to describe @var{fd}. 152@end table 153 154You can open an image using pre-opened file descriptors from an fd set: 155@example 156qemu-system-i386 157-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 158-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 159-drive file=/dev/fdset/2,index=0,media=disk 160@end example 161ETEXI 162 163DEF("set", HAS_ARG, QEMU_OPTION_set, 164 "-set group.id.arg=value\n" 165 " set <arg> parameter for item <id> of type <group>\n" 166 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL) 167STEXI 168@item -set @var{group}.@var{id}.@var{arg}=@var{value} 169@findex -set 170Set parameter @var{arg} for item @var{id} of type @var{group}\n" 171ETEXI 172 173DEF("global", HAS_ARG, QEMU_OPTION_global, 174 "-global driver.prop=value\n" 175 " set a global default for a driver property\n", 176 QEMU_ARCH_ALL) 177STEXI 178@item -global @var{driver}.@var{prop}=@var{value} 179@findex -global 180Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.: 181 182@example 183qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk 184@end example 185 186In particular, you can use this to set driver properties for devices which are 187created automatically by the machine model. To create a device which is not 188created automatically and set properties on it, use -@option{device}. 189ETEXI 190 191DEF("boot", HAS_ARG, QEMU_OPTION_boot, 192 "-boot [order=drives][,once=drives][,menu=on|off]\n" 193 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n" 194 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n" 195 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n" 196 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n" 197 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n", 198 QEMU_ARCH_ALL) 199STEXI 200@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] 201@findex -boot 202Specify boot order @var{drives} as a string of drive letters. Valid 203drive letters depend on the target achitecture. The x86 PC uses: a, b 204(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot 205from network adapter 1-4), hard disk boot is the default. To apply a 206particular boot order only on the first startup, specify it via 207@option{once}. 208 209Interactive boot menus/prompts can be enabled via @option{menu=on} as far 210as firmware/BIOS supports them. The default is non-interactive boot. 211 212A splash picture could be passed to bios, enabling user to show it as logo, 213when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS 214supports them. Currently Seabios for X86 system support it. 215limitation: The splash file could be a jpeg file or a BMP file in 24 BPP 216format(true color). The resolution should be supported by the SVGA mode, so 217the recommended is 320x240, 640x480, 800x640. 218 219A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms 220when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not 221reboot, qemu passes '-1' to bios by default. Currently Seabios for X86 222system support it. 223 224Do strict boot via @option{strict=on} as far as firmware/BIOS 225supports it. This only effects when boot priority is changed by 226bootindex options. The default is non-strict boot. 227 228@example 229# try to boot from network first, then from hard disk 230qemu-system-i386 -boot order=nc 231# boot from CD-ROM first, switch back to default order after reboot 232qemu-system-i386 -boot once=d 233# boot with a splash picture for 5 seconds. 234qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000 235@end example 236 237Note: The legacy format '-boot @var{drives}' is still supported but its 238use is discouraged as it may be removed from future versions. 239ETEXI 240 241DEF("m", HAS_ARG, QEMU_OPTION_m, 242 "-m[emory] [size=]megs[,slots=n,maxmem=size]\n" 243 " configure guest RAM\n" 244 " size: initial amount of guest memory (default: " 245 stringify(DEFAULT_RAM_SIZE) "MiB)\n" 246 " slots: number of hotplug slots (default: none)\n" 247 " maxmem: maximum amount of guest memory (default: none)\n" 248 "NOTE: Some architectures might enforce a specific granularity\n", 249 QEMU_ARCH_ALL) 250STEXI 251@item -m [size=]@var{megs}[,slots=n,maxmem=size] 252@findex -m 253Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB. 254Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in 255megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem} 256could be used to set amount of hotpluggable memory slots and maximum amount of 257memory. Note that @var{maxmem} must be aligned to the page size. 258 259For example, the following command-line sets the guest startup RAM size to 2601GB, creates 3 slots to hotplug additional memory and sets the maximum 261memory the guest can reach to 4GB: 262 263@example 264qemu-system-x86_64 -m 1G,slots=3,maxmem=4G 265@end example 266 267If @var{slots} and @var{maxmem} are not specified, memory hotplug won't 268be enabled and the guest startup RAM will never increase. 269ETEXI 270 271DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath, 272 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL) 273STEXI 274@item -mem-path @var{path} 275@findex -mem-path 276Allocate guest RAM from a temporarily created file in @var{path}. 277ETEXI 278 279DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc, 280 "-mem-prealloc preallocate guest memory (use with -mem-path)\n", 281 QEMU_ARCH_ALL) 282STEXI 283@item -mem-prealloc 284@findex -mem-prealloc 285Preallocate memory when using -mem-path. 286ETEXI 287 288DEF("k", HAS_ARG, QEMU_OPTION_k, 289 "-k language use keyboard layout (for example 'fr' for French)\n", 290 QEMU_ARCH_ALL) 291STEXI 292@item -k @var{language} 293@findex -k 294Use keyboard layout @var{language} (for example @code{fr} for 295French). This option is only needed where it is not easy to get raw PC 296keycodes (e.g. on Macs, with some X11 servers or with a VNC 297display). You don't normally need to use it on PC/Linux or PC/Windows 298hosts. 299 300The available layouts are: 301@example 302ar de-ch es fo fr-ca hu ja mk no pt-br sv 303da en-gb et fr fr-ch is lt nl pl ru th 304de en-us fi fr-be hr it lv nl-be pt sl tr 305@end example 306 307The default is @code{en-us}. 308ETEXI 309 310 311DEF("audio-help", 0, QEMU_OPTION_audio_help, 312 "-audio-help print list of audio drivers and their options\n", 313 QEMU_ARCH_ALL) 314STEXI 315@item -audio-help 316@findex -audio-help 317Will show the audio subsystem help: list of drivers, tunable 318parameters. 319ETEXI 320 321DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw, 322 "-soundhw c1,... enable audio support\n" 323 " and only specified sound cards (comma separated list)\n" 324 " use '-soundhw help' to get the list of supported cards\n" 325 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL) 326STEXI 327@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all 328@findex -soundhw 329Enable audio and selected sound hardware. Use 'help' to print all 330available sound hardware. 331 332@example 333qemu-system-i386 -soundhw sb16,adlib disk.img 334qemu-system-i386 -soundhw es1370 disk.img 335qemu-system-i386 -soundhw ac97 disk.img 336qemu-system-i386 -soundhw hda disk.img 337qemu-system-i386 -soundhw all disk.img 338qemu-system-i386 -soundhw help 339@end example 340 341Note that Linux's i810_audio OSS kernel (for AC97) module might 342require manually specifying clocking. 343 344@example 345modprobe i810_audio clocking=48000 346@end example 347ETEXI 348 349DEF("balloon", HAS_ARG, QEMU_OPTION_balloon, 350 "-balloon none disable balloon device\n" 351 "-balloon virtio[,addr=str]\n" 352 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL) 353STEXI 354@item -balloon none 355@findex -balloon 356Disable balloon device. 357@item -balloon virtio[,addr=@var{addr}] 358Enable virtio balloon device (default), optionally with PCI address 359@var{addr}. 360ETEXI 361 362DEF("device", HAS_ARG, QEMU_OPTION_device, 363 "-device driver[,prop[=value][,...]]\n" 364 " add device (based on driver)\n" 365 " prop=value,... sets driver properties\n" 366 " use '-device help' to print all possible drivers\n" 367 " use '-device driver,help' to print all possible properties\n", 368 QEMU_ARCH_ALL) 369STEXI 370@item -device @var{driver}[,@var{prop}[=@var{value}][,...]] 371@findex -device 372Add device @var{driver}. @var{prop}=@var{value} sets driver 373properties. Valid properties depend on the driver. To get help on 374possible drivers and properties, use @code{-device help} and 375@code{-device @var{driver},help}. 376ETEXI 377 378DEF("name", HAS_ARG, QEMU_OPTION_name, 379 "-name string1[,process=string2][,debug-threads=on|off]\n" 380 " set the name of the guest\n" 381 " string1 sets the window title and string2 the process name (on Linux)\n" 382 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n" 383 " NOTE: The thread names are for debugging and not a stable API.\n", 384 QEMU_ARCH_ALL) 385STEXI 386@item -name @var{name} 387@findex -name 388Sets the @var{name} of the guest. 389This name will be displayed in the SDL window caption. 390The @var{name} will also be used for the VNC server. 391Also optionally set the top visible process name in Linux. 392Naming of individual threads can also be enabled on Linux to aid debugging. 393ETEXI 394 395DEF("uuid", HAS_ARG, QEMU_OPTION_uuid, 396 "-uuid %08x-%04x-%04x-%04x-%012x\n" 397 " specify machine UUID\n", QEMU_ARCH_ALL) 398STEXI 399@item -uuid @var{uuid} 400@findex -uuid 401Set system UUID. 402ETEXI 403 404STEXI 405@end table 406ETEXI 407DEFHEADING() 408 409DEFHEADING(Block device options:) 410STEXI 411@table @option 412ETEXI 413 414DEF("fda", HAS_ARG, QEMU_OPTION_fda, 415 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL) 416DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL) 417STEXI 418@item -fda @var{file} 419@item -fdb @var{file} 420@findex -fda 421@findex -fdb 422Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). 423ETEXI 424 425DEF("hda", HAS_ARG, QEMU_OPTION_hda, 426 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL) 427DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL) 428DEF("hdc", HAS_ARG, QEMU_OPTION_hdc, 429 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL) 430DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL) 431STEXI 432@item -hda @var{file} 433@item -hdb @var{file} 434@item -hdc @var{file} 435@item -hdd @var{file} 436@findex -hda 437@findex -hdb 438@findex -hdc 439@findex -hdd 440Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}). 441ETEXI 442 443DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom, 444 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n", 445 QEMU_ARCH_ALL) 446STEXI 447@item -cdrom @var{file} 448@findex -cdrom 449Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and 450@option{-cdrom} at the same time). You can use the host CD-ROM by 451using @file{/dev/cdrom} as filename (@pxref{host_drives}). 452ETEXI 453 454DEF("drive", HAS_ARG, QEMU_OPTION_drive, 455 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" 456 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n" 457 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n" 458 " [,serial=s][,addr=A][,rerror=ignore|stop|report]\n" 459 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n" 460 " [,readonly=on|off][,copy-on-read=on|off]\n" 461 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n" 462 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n" 463 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n" 464 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n" 465 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n" 466 " [[,iops_size=is]]\n" 467 " use 'file' as a drive image\n", QEMU_ARCH_ALL) 468STEXI 469@item -drive @var{option}[,@var{option}[,@var{option}[,...]]] 470@findex -drive 471 472Define a new drive. Valid options are: 473 474@table @option 475@item file=@var{file} 476This option defines which disk image (@pxref{disk_images}) to use with 477this drive. If the filename contains comma, you must double it 478(for instance, "file=my,,file" to use file "my,file"). 479 480Special files such as iSCSI devices can be specified using protocol 481specific URLs. See the section for "Device URL Syntax" for more information. 482@item if=@var{interface} 483This option defines on which type on interface the drive is connected. 484Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio. 485@item bus=@var{bus},unit=@var{unit} 486These options define where is connected the drive by defining the bus number and 487the unit id. 488@item index=@var{index} 489This option defines where is connected the drive by using an index in the list 490of available connectors of a given interface type. 491@item media=@var{media} 492This option defines the type of the media: disk or cdrom. 493@item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}] 494These options have the same definition as they have in @option{-hdachs}. 495@item snapshot=@var{snapshot} 496@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive 497(see @option{-snapshot}). 498@item cache=@var{cache} 499@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data. 500@item aio=@var{aio} 501@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO. 502@item discard=@var{discard} 503@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. 504@item format=@var{format} 505Specify which disk @var{format} will be used rather than detecting 506the format. Can be used to specifiy format=raw to avoid interpreting 507an untrusted format header. 508@item serial=@var{serial} 509This option specifies the serial number to assign to the device. 510@item addr=@var{addr} 511Specify the controller's PCI address (if=virtio only). 512@item werror=@var{action},rerror=@var{action} 513Specify which @var{action} to take on write and read errors. Valid actions are: 514"ignore" (ignore the error and try to continue), "stop" (pause QEMU), 515"report" (report the error to the guest), "enospc" (pause QEMU only if the 516host disk is full; report the error to the guest otherwise). 517The default setting is @option{werror=enospc} and @option{rerror=report}. 518@item readonly 519Open drive @option{file} as read-only. Guest write attempts will fail. 520@item copy-on-read=@var{copy-on-read} 521@var{copy-on-read} is "on" or "off" and enables whether to copy read backing 522file sectors into the image file. 523@item detect-zeroes=@var{detect-zeroes} 524@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic 525conversion of plain zero writes by the OS to driver specific optimized 526zero write commands. You may even choose "unmap" if @var{discard} is set 527to "unmap" to allow a zero write to be converted to an UNMAP operation. 528@end table 529 530By default, the @option{cache=writeback} mode is used. It will report data 531writes as completed as soon as the data is present in the host page cache. 532This is safe as long as your guest OS makes sure to correctly flush disk caches 533where needed. If your guest OS does not handle volatile disk write caches 534correctly and your host crashes or loses power, then the guest may experience 535data corruption. 536 537For such guests, you should consider using @option{cache=writethrough}. This 538means that the host page cache will be used to read and write data, but write 539notification will be sent to the guest only after QEMU has made sure to flush 540each write to the disk. Be aware that this has a major impact on performance. 541 542The host page cache can be avoided entirely with @option{cache=none}. This will 543attempt to do disk IO directly to the guest's memory. QEMU may still perform 544an internal copy of the data. Note that this is considered a writeback mode and 545the guest OS must handle the disk write cache correctly in order to avoid data 546corruption on host crashes. 547 548The host page cache can be avoided while only sending write notifications to 549the guest when the data has been flushed to the disk using 550@option{cache=directsync}. 551 552In case you don't care about data integrity over host failures, use 553@option{cache=unsafe}. This option tells QEMU that it never needs to write any 554data to the disk but can instead keep things in cache. If anything goes wrong, 555like your host losing power, the disk storage getting disconnected accidentally, 556etc. your image will most probably be rendered unusable. When using 557the @option{-snapshot} option, unsafe caching is always used. 558 559Copy-on-read avoids accessing the same backing file sectors repeatedly and is 560useful when the backing file is over a slow network. By default copy-on-read 561is off. 562 563Instead of @option{-cdrom} you can use: 564@example 565qemu-system-i386 -drive file=file,index=2,media=cdrom 566@end example 567 568Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can 569use: 570@example 571qemu-system-i386 -drive file=file,index=0,media=disk 572qemu-system-i386 -drive file=file,index=1,media=disk 573qemu-system-i386 -drive file=file,index=2,media=disk 574qemu-system-i386 -drive file=file,index=3,media=disk 575@end example 576 577You can open an image using pre-opened file descriptors from an fd set: 578@example 579qemu-system-i386 580-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 581-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 582-drive file=/dev/fdset/2,index=0,media=disk 583@end example 584 585You can connect a CDROM to the slave of ide0: 586@example 587qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom 588@end example 589 590If you don't specify the "file=" argument, you define an empty drive: 591@example 592qemu-system-i386 -drive if=ide,index=1,media=cdrom 593@end example 594 595You can connect a SCSI disk with unit ID 6 on the bus #0: 596@example 597qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6 598@end example 599 600Instead of @option{-fda}, @option{-fdb}, you can use: 601@example 602qemu-system-i386 -drive file=file,index=0,if=floppy 603qemu-system-i386 -drive file=file,index=1,if=floppy 604@end example 605 606By default, @var{interface} is "ide" and @var{index} is automatically 607incremented: 608@example 609qemu-system-i386 -drive file=a -drive file=b" 610@end example 611is interpreted like: 612@example 613qemu-system-i386 -hda a -hdb b 614@end example 615ETEXI 616 617DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock, 618 "-mtdblock file use 'file' as on-board Flash memory image\n", 619 QEMU_ARCH_ALL) 620STEXI 621@item -mtdblock @var{file} 622@findex -mtdblock 623Use @var{file} as on-board Flash memory image. 624ETEXI 625 626DEF("sd", HAS_ARG, QEMU_OPTION_sd, 627 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL) 628STEXI 629@item -sd @var{file} 630@findex -sd 631Use @var{file} as SecureDigital card image. 632ETEXI 633 634DEF("pflash", HAS_ARG, QEMU_OPTION_pflash, 635 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL) 636STEXI 637@item -pflash @var{file} 638@findex -pflash 639Use @var{file} as a parallel flash image. 640ETEXI 641 642DEF("snapshot", 0, QEMU_OPTION_snapshot, 643 "-snapshot write to temporary files instead of disk image files\n", 644 QEMU_ARCH_ALL) 645STEXI 646@item -snapshot 647@findex -snapshot 648Write to temporary files instead of disk image files. In this case, 649the raw disk image you use is not written back. You can however force 650the write back by pressing @key{C-a s} (@pxref{disk_images}). 651ETEXI 652 653DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \ 654 "-hdachs c,h,s[,t]\n" \ 655 " force hard disk 0 physical geometry and the optional BIOS\n" \ 656 " translation (t=none or lba) (usually QEMU can guess them)\n", 657 QEMU_ARCH_ALL) 658STEXI 659@item -hdachs @var{c},@var{h},@var{s},[,@var{t}] 660@findex -hdachs 661Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <= 662@var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS 663translation mode (@var{t}=none, lba or auto). Usually QEMU can guess 664all those parameters. This option is useful for old MS-DOS disk 665images. 666ETEXI 667 668DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev, 669 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n" 670 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n", 671 QEMU_ARCH_ALL) 672 673STEXI 674 675@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}] 676@findex -fsdev 677Define a new file system device. Valid options are: 678@table @option 679@item @var{fsdriver} 680This option specifies the fs driver backend to use. 681Currently "local", "handle" and "proxy" file system drivers are supported. 682@item id=@var{id} 683Specifies identifier for this device 684@item path=@var{path} 685Specifies the export path for the file system device. Files under 686this path will be available to the 9p client on the guest. 687@item security_model=@var{security_model} 688Specifies the security model to be used for this export path. 689Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 690In "passthrough" security model, files are stored using the same 691credentials as they are created on the guest. This requires QEMU 692to run as root. In "mapped-xattr" security model, some of the file 693attributes like uid, gid, mode bits and link target are stored as 694file attributes. For "mapped-file" these attributes are stored in the 695hidden .virtfs_metadata directory. Directories exported by this security model cannot 696interact with other unix tools. "none" security model is same as 697passthrough except the sever won't report failures if it fails to 698set file attributes like ownership. Security model is mandatory 699only for local fsdriver. Other fsdrivers (like handle, proxy) don't take 700security model as a parameter. 701@item writeout=@var{writeout} 702This is an optional argument. The only supported value is "immediate". 703This means that host page cache will be used to read and write data but 704write notification will be sent to the guest only when the data has been 705reported as written by the storage subsystem. 706@item readonly 707Enables exporting 9p share as a readonly mount for guests. By default 708read-write access is given. 709@item socket=@var{socket} 710Enables proxy filesystem driver to use passed socket file for communicating 711with virtfs-proxy-helper 712@item sock_fd=@var{sock_fd} 713Enables proxy filesystem driver to use passed socket descriptor for 714communicating with virtfs-proxy-helper. Usually a helper like libvirt 715will create socketpair and pass one of the fds as sock_fd 716@end table 717 718-fsdev option is used along with -device driver "virtio-9p-pci". 719@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag} 720Options for virtio-9p-pci driver are: 721@table @option 722@item fsdev=@var{id} 723Specifies the id value specified along with -fsdev option 724@item mount_tag=@var{mount_tag} 725Specifies the tag name to be used by the guest to mount this export point 726@end table 727 728ETEXI 729 730DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs, 731 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n" 732 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n", 733 QEMU_ARCH_ALL) 734 735STEXI 736 737@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}] 738@findex -virtfs 739 740The general form of a Virtual File system pass-through options are: 741@table @option 742@item @var{fsdriver} 743This option specifies the fs driver backend to use. 744Currently "local", "handle" and "proxy" file system drivers are supported. 745@item id=@var{id} 746Specifies identifier for this device 747@item path=@var{path} 748Specifies the export path for the file system device. Files under 749this path will be available to the 9p client on the guest. 750@item security_model=@var{security_model} 751Specifies the security model to be used for this export path. 752Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 753In "passthrough" security model, files are stored using the same 754credentials as they are created on the guest. This requires QEMU 755to run as root. In "mapped-xattr" security model, some of the file 756attributes like uid, gid, mode bits and link target are stored as 757file attributes. For "mapped-file" these attributes are stored in the 758hidden .virtfs_metadata directory. Directories exported by this security model cannot 759interact with other unix tools. "none" security model is same as 760passthrough except the sever won't report failures if it fails to 761set file attributes like ownership. Security model is mandatory only 762for local fsdriver. Other fsdrivers (like handle, proxy) don't take security 763model as a parameter. 764@item writeout=@var{writeout} 765This is an optional argument. The only supported value is "immediate". 766This means that host page cache will be used to read and write data but 767write notification will be sent to the guest only when the data has been 768reported as written by the storage subsystem. 769@item readonly 770Enables exporting 9p share as a readonly mount for guests. By default 771read-write access is given. 772@item socket=@var{socket} 773Enables proxy filesystem driver to use passed socket file for 774communicating with virtfs-proxy-helper. Usually a helper like libvirt 775will create socketpair and pass one of the fds as sock_fd 776@item sock_fd 777Enables proxy filesystem driver to use passed 'sock_fd' as the socket 778descriptor for interfacing with virtfs-proxy-helper 779@end table 780ETEXI 781 782DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth, 783 "-virtfs_synth Create synthetic file system image\n", 784 QEMU_ARCH_ALL) 785STEXI 786@item -virtfs_synth 787@findex -virtfs_synth 788Create synthetic file system image 789ETEXI 790 791STEXI 792@end table 793ETEXI 794DEFHEADING() 795 796DEFHEADING(USB options:) 797STEXI 798@table @option 799ETEXI 800 801DEF("usb", 0, QEMU_OPTION_usb, 802 "-usb enable the USB driver (will be the default soon)\n", 803 QEMU_ARCH_ALL) 804STEXI 805@item -usb 806@findex -usb 807Enable the USB driver (will be the default soon) 808ETEXI 809 810DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice, 811 "-usbdevice name add the host or guest USB device 'name'\n", 812 QEMU_ARCH_ALL) 813STEXI 814 815@item -usbdevice @var{devname} 816@findex -usbdevice 817Add the USB device @var{devname}. @xref{usb_devices}. 818 819@table @option 820 821@item mouse 822Virtual Mouse. This will override the PS/2 mouse emulation when activated. 823 824@item tablet 825Pointer device that uses absolute coordinates (like a touchscreen). This 826means QEMU is able to report the mouse position without having to grab the 827mouse. Also overrides the PS/2 mouse emulation when activated. 828 829@item disk:[format=@var{format}]:@var{file} 830Mass storage device based on file. The optional @var{format} argument 831will be used rather than detecting the format. Can be used to specifiy 832@code{format=raw} to avoid interpreting an untrusted format header. 833 834@item host:@var{bus}.@var{addr} 835Pass through the host device identified by @var{bus}.@var{addr} (Linux only). 836 837@item host:@var{vendor_id}:@var{product_id} 838Pass through the host device identified by @var{vendor_id}:@var{product_id} 839(Linux only). 840 841@item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev} 842Serial converter to host character device @var{dev}, see @code{-serial} for the 843available devices. 844 845@item braille 846Braille device. This will use BrlAPI to display the braille output on a real 847or fake device. 848 849@item net:@var{options} 850Network adapter that supports CDC ethernet and RNDIS protocols. 851 852@end table 853ETEXI 854 855STEXI 856@end table 857ETEXI 858DEFHEADING() 859 860DEFHEADING(Display options:) 861STEXI 862@table @option 863ETEXI 864 865DEF("display", HAS_ARG, QEMU_OPTION_display, 866 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n" 867 " [,window_close=on|off]|curses|none|\n" 868 " gtk[,grab_on_hover=on|off]|\n" 869 " vnc=<display>[,<optargs>]\n" 870 " select display type\n", QEMU_ARCH_ALL) 871STEXI 872@item -display @var{type} 873@findex -display 874Select type of display to use. This option is a replacement for the 875old style -sdl/-curses/... options. Valid values for @var{type} are 876@table @option 877@item sdl 878Display video output via SDL (usually in a separate graphics 879window; see the SDL documentation for other possibilities). 880@item curses 881Display video output via curses. For graphics device models which 882support a text mode, QEMU can display this output using a 883curses/ncurses interface. Nothing is displayed when the graphics 884device is in graphical mode or if the graphics device does not support 885a text mode. Generally only the VGA device models support text mode. 886@item none 887Do not display video output. The guest will still see an emulated 888graphics card, but its output will not be displayed to the QEMU 889user. This option differs from the -nographic option in that it 890only affects what is done with video output; -nographic also changes 891the destination of the serial and parallel port data. 892@item gtk 893Display video output in a GTK window. This interface provides drop-down 894menus and other UI elements to configure and control the VM during 895runtime. 896@item vnc 897Start a VNC server on display <arg> 898@end table 899ETEXI 900 901DEF("nographic", 0, QEMU_OPTION_nographic, 902 "-nographic disable graphical output and redirect serial I/Os to console\n", 903 QEMU_ARCH_ALL) 904STEXI 905@item -nographic 906@findex -nographic 907Normally, QEMU uses SDL to display the VGA output. With this option, 908you can totally disable graphical output so that QEMU is a simple 909command line application. The emulated serial port is redirected on 910the console and muxed with the monitor (unless redirected elsewhere 911explicitly). Therefore, you can still use QEMU to debug a Linux kernel 912with a serial console. Use @key{C-a h} for help on switching between 913the console and monitor. 914ETEXI 915 916DEF("curses", 0, QEMU_OPTION_curses, 917 "-curses use a curses/ncurses interface instead of SDL\n", 918 QEMU_ARCH_ALL) 919STEXI 920@item -curses 921@findex -curses 922Normally, QEMU uses SDL to display the VGA output. With this option, 923QEMU can display the VGA output when in text mode using a 924curses/ncurses interface. Nothing is displayed in graphical mode. 925ETEXI 926 927DEF("no-frame", 0, QEMU_OPTION_no_frame, 928 "-no-frame open SDL window without a frame and window decorations\n", 929 QEMU_ARCH_ALL) 930STEXI 931@item -no-frame 932@findex -no-frame 933Do not use decorations for SDL windows and start them using the whole 934available screen space. This makes the using QEMU in a dedicated desktop 935workspace more convenient. 936ETEXI 937 938DEF("alt-grab", 0, QEMU_OPTION_alt_grab, 939 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n", 940 QEMU_ARCH_ALL) 941STEXI 942@item -alt-grab 943@findex -alt-grab 944Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also 945affects the special keys (for fullscreen, monitor-mode switching, etc). 946ETEXI 947 948DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab, 949 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n", 950 QEMU_ARCH_ALL) 951STEXI 952@item -ctrl-grab 953@findex -ctrl-grab 954Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also 955affects the special keys (for fullscreen, monitor-mode switching, etc). 956ETEXI 957 958DEF("no-quit", 0, QEMU_OPTION_no_quit, 959 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL) 960STEXI 961@item -no-quit 962@findex -no-quit 963Disable SDL window close capability. 964ETEXI 965 966DEF("sdl", 0, QEMU_OPTION_sdl, 967 "-sdl enable SDL\n", QEMU_ARCH_ALL) 968STEXI 969@item -sdl 970@findex -sdl 971Enable SDL. 972ETEXI 973 974DEF("spice", HAS_ARG, QEMU_OPTION_spice, 975 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n" 976 " [,x509-key-file=<file>][,x509-key-password=<file>]\n" 977 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n" 978 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n" 979 " [,tls-ciphers=<list>]\n" 980 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n" 981 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n" 982 " [,sasl][,password=<secret>][,disable-ticketing]\n" 983 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n" 984 " [,jpeg-wan-compression=[auto|never|always]]\n" 985 " [,zlib-glz-wan-compression=[auto|never|always]]\n" 986 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n" 987 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n" 988 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n" 989 " enable spice\n" 990 " at least one of {port, tls-port} is mandatory\n", 991 QEMU_ARCH_ALL) 992STEXI 993@item -spice @var{option}[,@var{option}[,...]] 994@findex -spice 995Enable the spice remote desktop protocol. Valid options are 996 997@table @option 998 999@item port=<nr> 1000Set the TCP port spice is listening on for plaintext channels. 1001 1002@item addr=<addr> 1003Set the IP address spice is listening on. Default is any address. 1004 1005@item ipv4 1006@item ipv6 1007@item unix 1008Force using the specified IP version. 1009 1010@item password=<secret> 1011Set the password you need to authenticate. 1012 1013@item sasl 1014Require that the client use SASL to authenticate with the spice. 1015The exact choice of authentication method used is controlled from the 1016system / user's SASL configuration file for the 'qemu' service. This 1017is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1018unprivileged user, an environment variable SASL_CONF_PATH can be used 1019to make it search alternate locations for the service config. 1020While some SASL auth methods can also provide data encryption (eg GSSAPI), 1021it is recommended that SASL always be combined with the 'tls' and 1022'x509' settings to enable use of SSL and server certificates. This 1023ensures a data encryption preventing compromise of authentication 1024credentials. 1025 1026@item disable-ticketing 1027Allow client connects without authentication. 1028 1029@item disable-copy-paste 1030Disable copy paste between the client and the guest. 1031 1032@item disable-agent-file-xfer 1033Disable spice-vdagent based file-xfer between the client and the guest. 1034 1035@item tls-port=<nr> 1036Set the TCP port spice is listening on for encrypted channels. 1037 1038@item x509-dir=<dir> 1039Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir 1040 1041@item x509-key-file=<file> 1042@item x509-key-password=<file> 1043@item x509-cert-file=<file> 1044@item x509-cacert-file=<file> 1045@item x509-dh-key-file=<file> 1046The x509 file names can also be configured individually. 1047 1048@item tls-ciphers=<list> 1049Specify which ciphers to use. 1050 1051@item tls-channel=[main|display|cursor|inputs|record|playback] 1052@item plaintext-channel=[main|display|cursor|inputs|record|playback] 1053Force specific channel to be used with or without TLS encryption. The 1054options can be specified multiple times to configure multiple 1055channels. The special name "default" can be used to set the default 1056mode. For channels which are not explicitly forced into one mode the 1057spice client is allowed to pick tls/plaintext as he pleases. 1058 1059@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off] 1060Configure image compression (lossless). 1061Default is auto_glz. 1062 1063@item jpeg-wan-compression=[auto|never|always] 1064@item zlib-glz-wan-compression=[auto|never|always] 1065Configure wan image compression (lossy for slow links). 1066Default is auto. 1067 1068@item streaming-video=[off|all|filter] 1069Configure video stream detection. Default is filter. 1070 1071@item agent-mouse=[on|off] 1072Enable/disable passing mouse events via vdagent. Default is on. 1073 1074@item playback-compression=[on|off] 1075Enable/disable audio stream compression (using celt 0.5.1). Default is on. 1076 1077@item seamless-migration=[on|off] 1078Enable/disable spice seamless migration. Default is off. 1079 1080@end table 1081ETEXI 1082 1083DEF("portrait", 0, QEMU_OPTION_portrait, 1084 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n", 1085 QEMU_ARCH_ALL) 1086STEXI 1087@item -portrait 1088@findex -portrait 1089Rotate graphical output 90 deg left (only PXA LCD). 1090ETEXI 1091 1092DEF("rotate", HAS_ARG, QEMU_OPTION_rotate, 1093 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n", 1094 QEMU_ARCH_ALL) 1095STEXI 1096@item -rotate @var{deg} 1097@findex -rotate 1098Rotate graphical output some deg left (only PXA LCD). 1099ETEXI 1100 1101DEF("vga", HAS_ARG, QEMU_OPTION_vga, 1102 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|none]\n" 1103 " select video card type\n", QEMU_ARCH_ALL) 1104STEXI 1105@item -vga @var{type} 1106@findex -vga 1107Select type of VGA card to emulate. Valid values for @var{type} are 1108@table @option 1109@item cirrus 1110Cirrus Logic GD5446 Video card. All Windows versions starting from 1111Windows 95 should recognize and use this graphic card. For optimal 1112performances, use 16 bit color depth in the guest and the host OS. 1113(This one is the default) 1114@item std 1115Standard VGA card with Bochs VBE extensions. If your guest OS 1116supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want 1117to use high resolution modes (>= 1280x1024x16) then you should use 1118this option. 1119@item vmware 1120VMWare SVGA-II compatible adapter. Use it if you have sufficiently 1121recent XFree86/XOrg server or Windows guest with a driver for this 1122card. 1123@item qxl 1124QXL paravirtual graphic card. It is VGA compatible (including VESA 11252.0 VBE support). Works best with qxl guest drivers installed though. 1126Recommended choice when using the spice protocol. 1127@item tcx 1128(sun4m only) Sun TCX framebuffer. This is the default framebuffer for 1129sun4m machines and offers both 8-bit and 24-bit colour depths at a 1130fixed resolution of 1024x768. 1131@item cg3 1132(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer 1133for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP) 1134resolutions aimed at people wishing to run older Solaris versions. 1135@item none 1136Disable VGA card. 1137@end table 1138ETEXI 1139 1140DEF("full-screen", 0, QEMU_OPTION_full_screen, 1141 "-full-screen start in full screen\n", QEMU_ARCH_ALL) 1142STEXI 1143@item -full-screen 1144@findex -full-screen 1145Start in full screen. 1146ETEXI 1147 1148DEF("g", 1, QEMU_OPTION_g , 1149 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n", 1150 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 1151STEXI 1152@item -g @var{width}x@var{height}[x@var{depth}] 1153@findex -g 1154Set the initial graphical resolution and depth (PPC, SPARC only). 1155ETEXI 1156 1157DEF("vnc", HAS_ARG, QEMU_OPTION_vnc , 1158 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL) 1159STEXI 1160@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]] 1161@findex -vnc 1162Normally, QEMU uses SDL to display the VGA output. With this option, 1163you can have QEMU listen on VNC display @var{display} and redirect the VGA 1164display over the VNC session. It is very useful to enable the usb 1165tablet device when using this option (option @option{-usbdevice 1166tablet}). When using the VNC display, you must use the @option{-k} 1167parameter to set the keyboard layout if you are not using en-us. Valid 1168syntax for the @var{display} is 1169 1170@table @option 1171 1172@item @var{host}:@var{d} 1173 1174TCP connections will only be allowed from @var{host} on display @var{d}. 1175By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can 1176be omitted in which case the server will accept connections from any host. 1177 1178@item unix:@var{path} 1179 1180Connections will be allowed over UNIX domain sockets where @var{path} is the 1181location of a unix socket to listen for connections on. 1182 1183@item none 1184 1185VNC is initialized but not started. The monitor @code{change} command 1186can be used to later start the VNC server. 1187 1188@end table 1189 1190Following the @var{display} value there may be one or more @var{option} flags 1191separated by commas. Valid options are 1192 1193@table @option 1194 1195@item reverse 1196 1197Connect to a listening VNC client via a ``reverse'' connection. The 1198client is specified by the @var{display}. For reverse network 1199connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument 1200is a TCP port number, not a display number. 1201 1202@item websocket 1203 1204Opens an additional TCP listening port dedicated to VNC Websocket connections. 1205By definition the Websocket port is 5700+@var{display}. If @var{host} is 1206specified connections will only be allowed from this host. 1207As an alternative the Websocket port could be specified by using 1208@code{websocket}=@var{port}. 1209TLS encryption for the Websocket connection is supported if the required 1210certificates are specified with the VNC option @option{x509}. 1211 1212@item password 1213 1214Require that password based authentication is used for client connections. 1215 1216The password must be set separately using the @code{set_password} command in 1217the @ref{pcsys_monitor}. The syntax to change your password is: 1218@code{set_password <protocol> <password>} where <protocol> could be either 1219"vnc" or "spice". 1220 1221If you would like to change <protocol> password expiration, you should use 1222@code{expire_password <protocol> <expiration-time>} where expiration time could 1223be one of the following options: now, never, +seconds or UNIX time of 1224expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800 1225to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this 1226date and time). 1227 1228You can also use keywords "now" or "never" for the expiration time to 1229allow <protocol> password to expire immediately or never expire. 1230 1231@item tls 1232 1233Require that client use TLS when communicating with the VNC server. This 1234uses anonymous TLS credentials so is susceptible to a man-in-the-middle 1235attack. It is recommended that this option be combined with either the 1236@option{x509} or @option{x509verify} options. 1237 1238@item x509=@var{/path/to/certificate/dir} 1239 1240Valid if @option{tls} is specified. Require that x509 credentials are used 1241for negotiating the TLS session. The server will send its x509 certificate 1242to the client. It is recommended that a password be set on the VNC server 1243to provide authentication of the client when this is used. The path following 1244this option specifies where the x509 certificates are to be loaded from. 1245See the @ref{vnc_security} section for details on generating certificates. 1246 1247@item x509verify=@var{/path/to/certificate/dir} 1248 1249Valid if @option{tls} is specified. Require that x509 credentials are used 1250for negotiating the TLS session. The server will send its x509 certificate 1251to the client, and request that the client send its own x509 certificate. 1252The server will validate the client's certificate against the CA certificate, 1253and reject clients when validation fails. If the certificate authority is 1254trusted, this is a sufficient authentication mechanism. You may still wish 1255to set a password on the VNC server as a second authentication layer. The 1256path following this option specifies where the x509 certificates are to 1257be loaded from. See the @ref{vnc_security} section for details on generating 1258certificates. 1259 1260@item sasl 1261 1262Require that the client use SASL to authenticate with the VNC server. 1263The exact choice of authentication method used is controlled from the 1264system / user's SASL configuration file for the 'qemu' service. This 1265is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1266unprivileged user, an environment variable SASL_CONF_PATH can be used 1267to make it search alternate locations for the service config. 1268While some SASL auth methods can also provide data encryption (eg GSSAPI), 1269it is recommended that SASL always be combined with the 'tls' and 1270'x509' settings to enable use of SSL and server certificates. This 1271ensures a data encryption preventing compromise of authentication 1272credentials. See the @ref{vnc_security} section for details on using 1273SASL authentication. 1274 1275@item acl 1276 1277Turn on access control lists for checking of the x509 client certificate 1278and SASL party. For x509 certs, the ACL check is made against the 1279certificate's distinguished name. This is something that looks like 1280@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is 1281made against the username, which depending on the SASL plugin, may 1282include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}. 1283When the @option{acl} flag is set, the initial access list will be 1284empty, with a @code{deny} policy. Thus no one will be allowed to 1285use the VNC server until the ACLs have been loaded. This can be 1286achieved using the @code{acl} monitor command. 1287 1288@item lossy 1289 1290Enable lossy compression methods (gradient, JPEG, ...). If this 1291option is set, VNC client may receive lossy framebuffer updates 1292depending on its encoding settings. Enabling this option can save 1293a lot of bandwidth at the expense of quality. 1294 1295@item non-adaptive 1296 1297Disable adaptive encodings. Adaptive encodings are enabled by default. 1298An adaptive encoding will try to detect frequently updated screen regions, 1299and send updates in these regions using a lossy encoding (like JPEG). 1300This can be really helpful to save bandwidth when playing videos. Disabling 1301adaptive encodings restores the original static behavior of encodings 1302like Tight. 1303 1304@item share=[allow-exclusive|force-shared|ignore] 1305 1306Set display sharing policy. 'allow-exclusive' allows clients to ask 1307for exclusive access. As suggested by the rfb spec this is 1308implemented by dropping other connections. Connecting multiple 1309clients in parallel requires all clients asking for a shared session 1310(vncviewer: -shared switch). This is the default. 'force-shared' 1311disables exclusive client access. Useful for shared desktop sessions, 1312where you don't want someone forgetting specify -shared disconnect 1313everybody else. 'ignore' completely ignores the shared flag and 1314allows everybody connect unconditionally. Doesn't conform to the rfb 1315spec but is traditional QEMU behavior. 1316 1317@end table 1318ETEXI 1319 1320STEXI 1321@end table 1322ETEXI 1323ARCHHEADING(, QEMU_ARCH_I386) 1324 1325ARCHHEADING(i386 target only:, QEMU_ARCH_I386) 1326STEXI 1327@table @option 1328ETEXI 1329 1330DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack, 1331 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n", 1332 QEMU_ARCH_I386) 1333STEXI 1334@item -win2k-hack 1335@findex -win2k-hack 1336Use it when installing Windows 2000 to avoid a disk full bug. After 1337Windows 2000 is installed, you no longer need this option (this option 1338slows down the IDE transfers). 1339ETEXI 1340 1341HXCOMM Deprecated by -rtc 1342DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386) 1343 1344DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk, 1345 "-no-fd-bootchk disable boot signature checking for floppy disks\n", 1346 QEMU_ARCH_I386) 1347STEXI 1348@item -no-fd-bootchk 1349@findex -no-fd-bootchk 1350Disable boot signature checking for floppy disks in BIOS. May 1351be needed to boot from old floppy disks. 1352ETEXI 1353 1354DEF("no-acpi", 0, QEMU_OPTION_no_acpi, 1355 "-no-acpi disable ACPI\n", QEMU_ARCH_I386) 1356STEXI 1357@item -no-acpi 1358@findex -no-acpi 1359Disable ACPI (Advanced Configuration and Power Interface) support. Use 1360it if your guest OS complains about ACPI problems (PC target machine 1361only). 1362ETEXI 1363 1364DEF("no-hpet", 0, QEMU_OPTION_no_hpet, 1365 "-no-hpet disable HPET\n", QEMU_ARCH_I386) 1366STEXI 1367@item -no-hpet 1368@findex -no-hpet 1369Disable HPET support. 1370ETEXI 1371 1372DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable, 1373 "-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" 1374 " ACPI table description\n", QEMU_ARCH_I386) 1375STEXI 1376@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}]...] 1377@findex -acpitable 1378Add ACPI table with specified header fields and context from specified files. 1379For file=, take whole ACPI table from the specified files, including all 1380ACPI headers (possible overridden by other options). 1381For data=, only data 1382portion of the table is used, all header information is specified in the 1383command line. 1384ETEXI 1385 1386DEF("smbios", HAS_ARG, QEMU_OPTION_smbios, 1387 "-smbios file=binary\n" 1388 " load SMBIOS entry from binary file\n" 1389 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n" 1390 " [,uefi=on|off]\n" 1391 " specify SMBIOS type 0 fields\n" 1392 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1393 " [,uuid=uuid][,sku=str][,family=str]\n" 1394 " specify SMBIOS type 1 fields\n" 1395 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1396 " [,asset=str][,location=str]\n" 1397 " specify SMBIOS type 2 fields\n" 1398 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n" 1399 " [,sku=str]\n" 1400 " specify SMBIOS type 3 fields\n" 1401 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n" 1402 " [,asset=str][,part=str]\n" 1403 " specify SMBIOS type 4 fields\n" 1404 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n" 1405 " [,asset=str][,part=str][,speed=%d]\n" 1406 " specify SMBIOS type 17 fields\n", 1407 QEMU_ARCH_I386) 1408STEXI 1409@item -smbios file=@var{binary} 1410@findex -smbios 1411Load SMBIOS entry from binary file. 1412 1413@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off] 1414Specify SMBIOS type 0 fields 1415 1416@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}] 1417Specify SMBIOS type 1 fields 1418 1419@item -smbios type=2[,manufacturer=@var{str}][,product=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,location=@var{str}][,family=@var{str}] 1420Specify SMBIOS type 2 fields 1421 1422@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}] 1423Specify SMBIOS type 3 fields 1424 1425@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}] 1426Specify SMBIOS type 4 fields 1427 1428@item -smbios type=17[,loc_pfx=@var{str}][,bank=@var{str}][,manufacturer=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}][,speed=@var{%d}] 1429Specify SMBIOS type 17 fields 1430ETEXI 1431 1432STEXI 1433@end table 1434ETEXI 1435DEFHEADING() 1436 1437DEFHEADING(Network options:) 1438STEXI 1439@table @option 1440ETEXI 1441 1442HXCOMM Legacy slirp options (now moved to -net user): 1443#ifdef CONFIG_SLIRP 1444DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL) 1445DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL) 1446DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL) 1447#ifndef _WIN32 1448DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL) 1449#endif 1450#endif 1451 1452DEF("net", HAS_ARG, QEMU_OPTION_net, 1453 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n" 1454 " create a new Network Interface Card and connect it to VLAN 'n'\n" 1455#ifdef CONFIG_SLIRP 1456 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=on|off]\n" 1457 " [,hostname=host][,dhcpstart=addr][,dns=addr][,dnssearch=domain][,tftp=dir]\n" 1458 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]" 1459#ifndef _WIN32 1460 "[,smb=dir[,smbserver=addr]]\n" 1461#endif 1462 " connect the user mode network stack to VLAN 'n', configure its\n" 1463 " DHCP server and enabled optional services\n" 1464#endif 1465#ifdef _WIN32 1466 "-net tap[,vlan=n][,name=str],ifname=name\n" 1467 " connect the host TAP network interface to VLAN 'n'\n" 1468#else 1469 "-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" 1470 " connect the host TAP network interface to VLAN 'n'\n" 1471 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n" 1472 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n" 1473 " to deconfigure it\n" 1474 " use '[down]script=no' to disable script execution\n" 1475 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n" 1476 " configure it\n" 1477 " use 'fd=h' to connect to an already opened TAP interface\n" 1478 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n" 1479 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n" 1480 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n" 1481 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n" 1482 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" 1483 " use vhost=on to enable experimental in kernel accelerator\n" 1484 " (only has effect for virtio guests which use MSIX)\n" 1485 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n" 1486 " use 'vhostfd=h' to connect to an already opened vhost net device\n" 1487 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n" 1488 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n" 1489 "-net bridge[,vlan=n][,name=str][,br=bridge][,helper=helper]\n" 1490 " connects a host TAP network interface to a host bridge device 'br'\n" 1491 " (default=" DEFAULT_BRIDGE_INTERFACE ") using the program 'helper'\n" 1492 " (default=" DEFAULT_BRIDGE_HELPER ")\n" 1493#endif 1494#ifdef __linux__ 1495 "-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" 1496 " connect the VLAN to an Ethernet over L2TPv3 pseudowire\n" 1497 " Linux kernel 3.3+ as well as most routers can talk\n" 1498 " L2TPv3. This transport allows connecting a VM to a VM,\n" 1499 " VM to a router and even VM to Host. It is a nearly-universal\n" 1500 " standard (RFC3391). Note - this implementation uses static\n" 1501 " pre-configured tunnels (same as the Linux kernel).\n" 1502 " use 'src=' to specify source address\n" 1503 " use 'dst=' to specify destination address\n" 1504 " use 'udp=on' to specify udp encapsulation\n" 1505 " use 'srcport=' to specify source udp port\n" 1506 " use 'dstport=' to specify destination udp port\n" 1507 " use 'ipv6=on' to force v6\n" 1508 " L2TPv3 uses cookies to prevent misconfiguration as\n" 1509 " well as a weak security measure\n" 1510 " use 'rxcookie=0x012345678' to specify a rxcookie\n" 1511 " use 'txcookie=0x012345678' to specify a txcookie\n" 1512 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n" 1513 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n" 1514 " use 'pincounter=on' to work around broken counter handling in peer\n" 1515 " use 'offset=X' to add an extra offset between header and data\n" 1516#endif 1517 "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n" 1518 " connect the vlan 'n' to another VLAN using a socket connection\n" 1519 "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port[,localaddr=addr]]\n" 1520 " connect the vlan 'n' to multicast maddr and port\n" 1521 " use 'localaddr=addr' to specify the host address to send packets from\n" 1522 "-net socket[,vlan=n][,name=str][,fd=h][,udp=host:port][,localaddr=host:port]\n" 1523 " connect the vlan 'n' to another VLAN using an UDP tunnel\n" 1524#ifdef CONFIG_VDE 1525 "-net vde[,vlan=n][,name=str][,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n" 1526 " connect the vlan 'n' to port 'n' of a vde switch running\n" 1527 " on host and listening for incoming connections on 'socketpath'.\n" 1528 " Use group 'groupname' and mode 'octalmode' to change default\n" 1529 " ownership and permissions for communication port.\n" 1530#endif 1531#ifdef CONFIG_NETMAP 1532 "-net netmap,ifname=name[,devname=nmname]\n" 1533 " attach to the existing netmap-enabled network interface 'name', or to a\n" 1534 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n" 1535 " netmap device, defaults to '/dev/netmap')\n" 1536#endif 1537 "-net dump[,vlan=n][,file=f][,len=n]\n" 1538 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n" 1539 "-net none use it alone to have zero network devices. If no -net option\n" 1540 " is provided, the default is '-net nic -net user'\n", QEMU_ARCH_ALL) 1541DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, 1542 "-netdev [" 1543#ifdef CONFIG_SLIRP 1544 "user|" 1545#endif 1546 "tap|" 1547 "bridge|" 1548#ifdef CONFIG_VDE 1549 "vde|" 1550#endif 1551#ifdef CONFIG_NETMAP 1552 "netmap|" 1553#endif 1554 "vhost-user|" 1555 "socket|" 1556 "hubport],id=str[,option][,option][,...]\n", QEMU_ARCH_ALL) 1557STEXI 1558@item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}] 1559@findex -net 1560Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n} 1561= 0 is the default). The NIC is an e1000 by default on the PC 1562target. Optionally, the MAC address can be changed to @var{mac}, the 1563device address set to @var{addr} (PCI cards only), 1564and a @var{name} can be assigned for use in monitor commands. 1565Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors 1566that the card should have; this option currently only affects virtio cards; set 1567@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single 1568NIC is created. QEMU can emulate several different models of network card. 1569Valid values for @var{type} are 1570@code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er}, 1571@code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139}, 1572@code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}. 1573Not all devices are supported on all targets. Use @code{-net nic,model=help} 1574for a list of available devices for your target. 1575 1576@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...] 1577@findex -netdev 1578@item -net user[,@var{option}][,@var{option}][,...] 1579Use the user mode network stack which requires no administrator 1580privilege to run. Valid options are: 1581 1582@table @option 1583@item vlan=@var{n} 1584Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default). 1585 1586@item id=@var{id} 1587@item name=@var{name} 1588Assign symbolic name for use in monitor commands. 1589 1590@item net=@var{addr}[/@var{mask}] 1591Set IP network address the guest will see. Optionally specify the netmask, 1592either in the form a.b.c.d or as number of valid top-most bits. Default is 159310.0.2.0/24. 1594 1595@item host=@var{addr} 1596Specify the guest-visible address of the host. Default is the 2nd IP in the 1597guest network, i.e. x.x.x.2. 1598 1599@item restrict=on|off 1600If this option is enabled, the guest will be isolated, i.e. it will not be 1601able to contact the host and no guest IP packets will be routed over the host 1602to the outside. This option does not affect any explicitly set forwarding rules. 1603 1604@item hostname=@var{name} 1605Specifies the client hostname reported by the built-in DHCP server. 1606 1607@item dhcpstart=@var{addr} 1608Specify the first of the 16 IPs the built-in DHCP server can assign. Default 1609is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31. 1610 1611@item dns=@var{addr} 1612Specify the guest-visible address of the virtual nameserver. The address must 1613be different from the host address. Default is the 3rd IP in the guest network, 1614i.e. x.x.x.3. 1615 1616@item dnssearch=@var{domain} 1617Provides an entry for the domain-search list sent by the built-in 1618DHCP server. More than one domain suffix can be transmitted by specifying 1619this option multiple times. If supported, this will cause the guest to 1620automatically try to append the given domain suffix(es) in case a domain name 1621can not be resolved. 1622 1623Example: 1624@example 1625qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...] 1626@end example 1627 1628@item tftp=@var{dir} 1629When using the user mode network stack, activate a built-in TFTP 1630server. The files in @var{dir} will be exposed as the root of a TFTP server. 1631The TFTP client on the guest must be configured in binary mode (use the command 1632@code{bin} of the Unix TFTP client). 1633 1634@item bootfile=@var{file} 1635When using the user mode network stack, broadcast @var{file} as the BOOTP 1636filename. In conjunction with @option{tftp}, this can be used to network boot 1637a guest from a local directory. 1638 1639Example (using pxelinux): 1640@example 1641qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0 1642@end example 1643 1644@item smb=@var{dir}[,smbserver=@var{addr}] 1645When using the user mode network stack, activate a built-in SMB 1646server so that Windows OSes can access to the host files in @file{@var{dir}} 1647transparently. The IP address of the SMB server can be set to @var{addr}. By 1648default the 4th IP in the guest network is used, i.e. x.x.x.4. 1649 1650In the guest Windows OS, the line: 1651@example 165210.0.2.4 smbserver 1653@end example 1654must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me) 1655or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000). 1656 1657Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}. 1658 1659Note that a SAMBA server must be installed on the host OS. 1660QEMU was tested successfully with smbd versions from Red Hat 9, 1661Fedora Core 3 and OpenSUSE 11.x. 1662 1663@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport} 1664Redirect incoming TCP or UDP connections to the host port @var{hostport} to 1665the guest IP address @var{guestaddr} on guest port @var{guestport}. If 1666@var{guestaddr} is not specified, its value is x.x.x.15 (default first address 1667given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can 1668be bound to a specific host interface. If no connection type is set, TCP is 1669used. This option can be given multiple times. 1670 1671For example, to redirect host X11 connection from screen 1 to guest 1672screen 0, use the following: 1673 1674@example 1675# on the host 1676qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...] 1677# this host xterm should open in the guest X11 server 1678xterm -display :1 1679@end example 1680 1681To redirect telnet connections from host port 5555 to telnet port on 1682the guest, use the following: 1683 1684@example 1685# on the host 1686qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...] 1687telnet localhost 5555 1688@end example 1689 1690Then when you use on the host @code{telnet localhost 5555}, you 1691connect to the guest telnet server. 1692 1693@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev} 1694@item guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command} 1695Forward guest TCP connections to the IP address @var{server} on port @var{port} 1696to the character device @var{dev} or to a program executed by @var{cmd:command} 1697which gets spawned for each connection. This option can be given multiple times. 1698 1699You can either use a chardev directly and have that one used throughout QEMU's 1700lifetime, like in the following example: 1701 1702@example 1703# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever 1704# the guest accesses it 1705qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...] 1706@end example 1707 1708Or you can execute a command on every TCP connection established by the guest, 1709so that QEMU behaves similar to an inetd process for that virtual server: 1710 1711@example 1712# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 1713# and connect the TCP stream to its stdin/stdout 1714qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321' 1715@end example 1716 1717@end table 1718 1719Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still 1720processed and applied to -net user. Mixing them with the new configuration 1721syntax gives undefined results. Their use for new applications is discouraged 1722as they will be removed from future versions. 1723 1724@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}] 1725@item -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}] 1726Connect the host TAP network interface @var{name} to VLAN @var{n}. 1727 1728Use the network script @var{file} to configure it and the network script 1729@var{dfile} to deconfigure it. If @var{name} is not provided, the OS 1730automatically provides one. The default network configure script is 1731@file{/etc/qemu-ifup} and the default network deconfigure script is 1732@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no} 1733to disable script execution. 1734 1735If running QEMU as an unprivileged user, use the network helper 1736@var{helper} to configure the TAP interface. The default network 1737helper executable is @file{/path/to/qemu-bridge-helper}. 1738 1739@option{fd}=@var{h} can be used to specify the handle of an already 1740opened host TAP interface. 1741 1742Examples: 1743 1744@example 1745#launch a QEMU instance with the default network script 1746qemu-system-i386 linux.img -net nic -net tap 1747@end example 1748 1749@example 1750#launch a QEMU instance with two NICs, each one connected 1751#to a TAP device 1752qemu-system-i386 linux.img \ 1753 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \ 1754 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1 1755@end example 1756 1757@example 1758#launch a QEMU instance with the default network helper to 1759#connect a TAP device to bridge br0 1760qemu-system-i386 linux.img \ 1761 -net nic -net tap,"helper=/path/to/qemu-bridge-helper" 1762@end example 1763 1764@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}] 1765@item -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}] 1766Connect a host TAP network interface to a host bridge device. 1767 1768Use the network helper @var{helper} to configure the TAP interface and 1769attach it to the bridge. The default network helper executable is 1770@file{/path/to/qemu-bridge-helper} and the default bridge 1771device is @file{br0}. 1772 1773Examples: 1774 1775@example 1776#launch a QEMU instance with the default network helper to 1777#connect a TAP device to bridge br0 1778qemu-system-i386 linux.img -net bridge -net nic,model=virtio 1779@end example 1780 1781@example 1782#launch a QEMU instance with the default network helper to 1783#connect a TAP device to bridge qemubr0 1784qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio 1785@end example 1786 1787@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 1788@item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 1789 1790Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual 1791machine using a TCP socket connection. If @option{listen} is 1792specified, QEMU waits for incoming connections on @var{port} 1793(@var{host} is optional). @option{connect} is used to connect to 1794another QEMU instance using the @option{listen} option. @option{fd}=@var{h} 1795specifies an already opened TCP socket. 1796 1797Example: 1798@example 1799# launch a first QEMU instance 1800qemu-system-i386 linux.img \ 1801 -net nic,macaddr=52:54:00:12:34:56 \ 1802 -net socket,listen=:1234 1803# connect the VLAN 0 of this instance to the VLAN 0 1804# of the first instance 1805qemu-system-i386 linux.img \ 1806 -net nic,macaddr=52:54:00:12:34:57 \ 1807 -net socket,connect=127.0.0.1:1234 1808@end example 1809 1810@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 1811@item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 1812 1813Create a VLAN @var{n} shared with another QEMU virtual 1814machines using a UDP multicast socket, effectively making a bus for 1815every QEMU with same multicast address @var{maddr} and @var{port}. 1816NOTES: 1817@enumerate 1818@item 1819Several QEMU can be running on different hosts and share same bus (assuming 1820correct multicast setup for these hosts). 1821@item 1822mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see 1823@url{http://user-mode-linux.sf.net}. 1824@item 1825Use @option{fd=h} to specify an already opened UDP multicast socket. 1826@end enumerate 1827 1828Example: 1829@example 1830# launch one QEMU instance 1831qemu-system-i386 linux.img \ 1832 -net nic,macaddr=52:54:00:12:34:56 \ 1833 -net socket,mcast=230.0.0.1:1234 1834# launch another QEMU instance on same "bus" 1835qemu-system-i386 linux.img \ 1836 -net nic,macaddr=52:54:00:12:34:57 \ 1837 -net socket,mcast=230.0.0.1:1234 1838# launch yet another QEMU instance on same "bus" 1839qemu-system-i386 linux.img \ 1840 -net nic,macaddr=52:54:00:12:34:58 \ 1841 -net socket,mcast=230.0.0.1:1234 1842@end example 1843 1844Example (User Mode Linux compat.): 1845@example 1846# launch QEMU instance (note mcast address selected 1847# is UML's default) 1848qemu-system-i386 linux.img \ 1849 -net nic,macaddr=52:54:00:12:34:56 \ 1850 -net socket,mcast=239.192.168.1:1102 1851# launch UML 1852/path/to/linux ubd0=/path/to/root_fs eth0=mcast 1853@end example 1854 1855Example (send packets from host's 1.2.3.4): 1856@example 1857qemu-system-i386 linux.img \ 1858 -net nic,macaddr=52:54:00:12:34:56 \ 1859 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4 1860@end example 1861 1862@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}] 1863@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}] 1864Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular 1865protocol to transport Ethernet (and other Layer 2) data frames between 1866two systems. It is present in routers, firewalls and the Linux kernel 1867(from version 3.3 onwards). 1868 1869This transport allows a VM to communicate to another VM, router or firewall directly. 1870 1871@item src=@var{srcaddr} 1872 source address (mandatory) 1873@item dst=@var{dstaddr} 1874 destination address (mandatory) 1875@item udp 1876 select udp encapsulation (default is ip). 1877@item srcport=@var{srcport} 1878 source udp port. 1879@item dstport=@var{dstport} 1880 destination udp port. 1881@item ipv6 1882 force v6, otherwise defaults to v4. 1883@item rxcookie=@var{rxcookie} 1884@item txcookie=@var{txcookie} 1885 Cookies are a weak form of security in the l2tpv3 specification. 1886Their function is mostly to prevent misconfiguration. By default they are 32 1887bit. 1888@item cookie64 1889 Set cookie size to 64 bit instead of the default 32 1890@item counter=off 1891 Force a 'cut-down' L2TPv3 with no counter as in 1892draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00 1893@item pincounter=on 1894 Work around broken counter handling in peer. This may also help on 1895networks which have packet reorder. 1896@item offset=@var{offset} 1897 Add an extra offset between header and data 1898 1899For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan 1900on the remote Linux host 1.2.3.4: 1901@example 1902# Setup tunnel on linux host using raw ip as encapsulation 1903# on 1.2.3.4 1904ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \ 1905 encap udp udp_sport 16384 udp_dport 16384 1906ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \ 1907 0xFFFFFFFF peer_session_id 0xFFFFFFFF 1908ifconfig vmtunnel0 mtu 1500 1909ifconfig vmtunnel0 up 1910brctl addif br-lan vmtunnel0 1911 1912 1913# on 4.3.2.1 1914# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter 1915 1916qemu-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 1917 1918 1919@end example 1920 1921@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 1922@item -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 1923Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and 1924listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname} 1925and MODE @var{octalmode} to change default ownership and permissions for 1926communication port. This option is only available if QEMU has been compiled 1927with vde support enabled. 1928 1929Example: 1930@example 1931# launch vde switch 1932vde_switch -F -sock /tmp/myswitch 1933# launch QEMU instance 1934qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch 1935@end example 1936 1937@item -netdev hubport,id=@var{id},hubid=@var{hubid} 1938 1939Create a hub port on QEMU "vlan" @var{hubid}. 1940 1941The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single 1942netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the 1943required hub automatically. 1944 1945@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off] 1946 1947Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should 1948be a unix domain socket backed one. The vhost-user uses a specifically defined 1949protocol to pass vhost ioctl replacement messages to an application on the other 1950end of the socket. On non-MSIX guests, the feature can be forced with 1951@var{vhostforce}. 1952 1953Example: 1954@example 1955qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \ 1956 -numa node,memdev=mem \ 1957 -chardev socket,path=/path/to/socket \ 1958 -netdev type=vhost-user,id=net0,chardev=chr0 \ 1959 -device virtio-net-pci,netdev=net0 1960@end example 1961 1962@item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}] 1963Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default). 1964At most @var{len} bytes (64k by default) per packet are stored. The file format is 1965libpcap, so it can be analyzed with tools such as tcpdump or Wireshark. 1966 1967@item -net none 1968Indicate that no network devices should be configured. It is used to 1969override the default configuration (@option{-net nic -net user}) which 1970is activated if no @option{-net} options are provided. 1971ETEXI 1972 1973STEXI 1974@end table 1975ETEXI 1976DEFHEADING() 1977 1978DEFHEADING(Character device options:) 1979STEXI 1980 1981The general form of a character device option is: 1982@table @option 1983ETEXI 1984 1985DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, 1986 "-chardev null,id=id[,mux=on|off]\n" 1987 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n" 1988 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off] (tcp)\n" 1989 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off] (unix)\n" 1990 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" 1991 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n" 1992 "-chardev msmouse,id=id[,mux=on|off]\n" 1993 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n" 1994 " [,mux=on|off]\n" 1995 "-chardev ringbuf,id=id[,size=size]\n" 1996 "-chardev file,id=id,path=path[,mux=on|off]\n" 1997 "-chardev pipe,id=id,path=path[,mux=on|off]\n" 1998#ifdef _WIN32 1999 "-chardev console,id=id[,mux=on|off]\n" 2000 "-chardev serial,id=id,path=path[,mux=on|off]\n" 2001#else 2002 "-chardev pty,id=id[,mux=on|off]\n" 2003 "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n" 2004#endif 2005#ifdef CONFIG_BRLAPI 2006 "-chardev braille,id=id[,mux=on|off]\n" 2007#endif 2008#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 2009 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) 2010 "-chardev serial,id=id,path=path[,mux=on|off]\n" 2011 "-chardev tty,id=id,path=path[,mux=on|off]\n" 2012#endif 2013#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) 2014 "-chardev parallel,id=id,path=path[,mux=on|off]\n" 2015 "-chardev parport,id=id,path=path[,mux=on|off]\n" 2016#endif 2017#if defined(CONFIG_SPICE) 2018 "-chardev spicevmc,id=id,name=name[,debug=debug]\n" 2019 "-chardev spiceport,id=id,name=name[,debug=debug]\n" 2020#endif 2021 , QEMU_ARCH_ALL 2022) 2023 2024STEXI 2025@item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}] 2026@findex -chardev 2027Backend is one of: 2028@option{null}, 2029@option{socket}, 2030@option{udp}, 2031@option{msmouse}, 2032@option{vc}, 2033@option{ringbuf}, 2034@option{file}, 2035@option{pipe}, 2036@option{console}, 2037@option{serial}, 2038@option{pty}, 2039@option{stdio}, 2040@option{braille}, 2041@option{tty}, 2042@option{parallel}, 2043@option{parport}, 2044@option{spicevmc}. 2045@option{spiceport}. 2046The specific backend will determine the applicable options. 2047 2048All devices must have an id, which can be any string up to 127 characters long. 2049It is used to uniquely identify this device in other command line directives. 2050 2051A character device may be used in multiplexing mode by multiple front-ends. 2052The key sequence of @key{Control-a} and @key{c} will rotate the input focus 2053between attached front-ends. Specify @option{mux=on} to enable this mode. 2054 2055Options to each backend are described below. 2056 2057@item -chardev null ,id=@var{id} 2058A void device. This device will not emit any data, and will drop any data it 2059receives. The null backend does not take any options. 2060 2061@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}] 2062 2063Create a two-way stream socket, which can be either a TCP or a unix socket. A 2064unix socket will be created if @option{path} is specified. Behaviour is 2065undefined if TCP options are specified for a unix socket. 2066 2067@option{server} specifies that the socket shall be a listening socket. 2068 2069@option{nowait} specifies that QEMU should not block waiting for a client to 2070connect to a listening socket. 2071 2072@option{telnet} specifies that traffic on the socket should interpret telnet 2073escape sequences. 2074 2075@option{reconnect} sets the timeout for reconnecting on non-server sockets when 2076the remote end goes away. qemu will delay this many seconds and then attempt 2077to reconnect. Zero disables reconnecting, and is the default. 2078 2079TCP and unix socket options are given below: 2080 2081@table @option 2082 2083@item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay] 2084 2085@option{host} for a listening socket specifies the local address to be bound. 2086For a connecting socket species the remote host to connect to. @option{host} is 2087optional for listening sockets. If not specified it defaults to @code{0.0.0.0}. 2088 2089@option{port} for a listening socket specifies the local port to be bound. For a 2090connecting socket specifies the port on the remote host to connect to. 2091@option{port} can be given as either a port number or a service name. 2092@option{port} is required. 2093 2094@option{to} is only relevant to listening sockets. If it is specified, and 2095@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up 2096to and including @option{to} until it succeeds. @option{to} must be specified 2097as a port number. 2098 2099@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2100If neither is specified the socket may use either protocol. 2101 2102@option{nodelay} disables the Nagle algorithm. 2103 2104@item unix options: path=@var{path} 2105 2106@option{path} specifies the local path of the unix socket. @option{path} is 2107required. 2108 2109@end table 2110 2111@item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6] 2112 2113Sends all traffic from the guest to a remote host over UDP. 2114 2115@option{host} specifies the remote host to connect to. If not specified it 2116defaults to @code{localhost}. 2117 2118@option{port} specifies the port on the remote host to connect to. @option{port} 2119is required. 2120 2121@option{localaddr} specifies the local address to bind to. If not specified it 2122defaults to @code{0.0.0.0}. 2123 2124@option{localport} specifies the local port to bind to. If not specified any 2125available local port will be used. 2126 2127@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2128If neither is specified the device may use either protocol. 2129 2130@item -chardev msmouse ,id=@var{id} 2131 2132Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not 2133take any options. 2134 2135@item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]] 2136 2137Connect to a QEMU text console. @option{vc} may optionally be given a specific 2138size. 2139 2140@option{width} and @option{height} specify the width and height respectively of 2141the console, in pixels. 2142 2143@option{cols} and @option{rows} specify that the console be sized to fit a text 2144console with the given dimensions. 2145 2146@item -chardev ringbuf ,id=@var{id} [,size=@var{size}] 2147 2148Create a ring buffer with fixed size @option{size}. 2149@var{size} must be a power of two, and defaults to @code{64K}). 2150 2151@item -chardev file ,id=@var{id} ,path=@var{path} 2152 2153Log all traffic received from the guest to a file. 2154 2155@option{path} specifies the path of the file to be opened. This file will be 2156created if it does not already exist, and overwritten if it does. @option{path} 2157is required. 2158 2159@item -chardev pipe ,id=@var{id} ,path=@var{path} 2160 2161Create a two-way connection to the guest. The behaviour differs slightly between 2162Windows hosts and other hosts: 2163 2164On Windows, a single duplex pipe will be created at 2165@file{\\.pipe\@option{path}}. 2166 2167On other hosts, 2 pipes will be created called @file{@option{path}.in} and 2168@file{@option{path}.out}. Data written to @file{@option{path}.in} will be 2169received by the guest. Data written by the guest can be read from 2170@file{@option{path}.out}. QEMU will not create these fifos, and requires them to 2171be present. 2172 2173@option{path} forms part of the pipe path as described above. @option{path} is 2174required. 2175 2176@item -chardev console ,id=@var{id} 2177 2178Send traffic from the guest to QEMU's standard output. @option{console} does not 2179take any options. 2180 2181@option{console} is only available on Windows hosts. 2182 2183@item -chardev serial ,id=@var{id} ,path=@option{path} 2184 2185Send traffic from the guest to a serial device on the host. 2186 2187On Unix hosts serial will actually accept any tty device, 2188not only serial lines. 2189 2190@option{path} specifies the name of the serial device to open. 2191 2192@item -chardev pty ,id=@var{id} 2193 2194Create a new pseudo-terminal on the host and connect to it. @option{pty} does 2195not take any options. 2196 2197@option{pty} is not available on Windows hosts. 2198 2199@item -chardev stdio ,id=@var{id} [,signal=on|off] 2200Connect to standard input and standard output of the QEMU process. 2201 2202@option{signal} controls if signals are enabled on the terminal, that includes 2203exiting QEMU with the key sequence @key{Control-c}. This option is enabled by 2204default, use @option{signal=off} to disable it. 2205 2206@option{stdio} is not available on Windows hosts. 2207 2208@item -chardev braille ,id=@var{id} 2209 2210Connect to a local BrlAPI server. @option{braille} does not take any options. 2211 2212@item -chardev tty ,id=@var{id} ,path=@var{path} 2213 2214@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and 2215DragonFlyBSD hosts. It is an alias for @option{serial}. 2216 2217@option{path} specifies the path to the tty. @option{path} is required. 2218 2219@item -chardev parallel ,id=@var{id} ,path=@var{path} 2220@item -chardev parport ,id=@var{id} ,path=@var{path} 2221 2222@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts. 2223 2224Connect to a local parallel port. 2225 2226@option{path} specifies the path to the parallel port device. @option{path} is 2227required. 2228 2229@item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name} 2230 2231@option{spicevmc} is only available when spice support is built in. 2232 2233@option{debug} debug level for spicevmc 2234 2235@option{name} name of spice channel to connect to 2236 2237Connect to a spice virtual machine channel, such as vdiport. 2238 2239@item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name} 2240 2241@option{spiceport} is only available when spice support is built in. 2242 2243@option{debug} debug level for spicevmc 2244 2245@option{name} name of spice port to connect to 2246 2247Connect to a spice port, allowing a Spice client to handle the traffic 2248identified by a name (preferably a fqdn). 2249ETEXI 2250 2251STEXI 2252@end table 2253ETEXI 2254DEFHEADING() 2255 2256DEFHEADING(Device URL Syntax:) 2257STEXI 2258 2259In addition to using normal file images for the emulated storage devices, 2260QEMU can also use networked resources such as iSCSI devices. These are 2261specified using a special URL syntax. 2262 2263@table @option 2264@item iSCSI 2265iSCSI support allows QEMU to access iSCSI resources directly and use as 2266images for the guest storage. Both disk and cdrom images are supported. 2267 2268Syntax for specifying iSCSI LUNs is 2269``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>'' 2270 2271By default qemu will use the iSCSI initiator-name 2272'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command 2273line or a configuration file. 2274 2275 2276Example (without authentication): 2277@example 2278qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \ 2279 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \ 2280 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 2281@end example 2282 2283Example (CHAP username/password via URL): 2284@example 2285qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1 2286@end example 2287 2288Example (CHAP username/password via environment variables): 2289@example 2290LIBISCSI_CHAP_USERNAME="user" \ 2291LIBISCSI_CHAP_PASSWORD="password" \ 2292qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 2293@end example 2294 2295iSCSI support is an optional feature of QEMU and only available when 2296compiled and linked against libiscsi. 2297ETEXI 2298DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi, 2299 "-iscsi [user=user][,password=password]\n" 2300 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n" 2301 " [,initiator-name=initiator-iqn][,id=target-iqn]\n" 2302 " iSCSI session parameters\n", QEMU_ARCH_ALL) 2303STEXI 2304 2305iSCSI parameters such as username and password can also be specified via 2306a configuration file. See qemu-doc for more information and examples. 2307 2308@item NBD 2309QEMU supports NBD (Network Block Devices) both using TCP protocol as well 2310as Unix Domain Sockets. 2311 2312Syntax for specifying a NBD device using TCP 2313``nbd:<server-ip>:<port>[:exportname=<export>]'' 2314 2315Syntax for specifying a NBD device using Unix Domain Sockets 2316``nbd:unix:<domain-socket>[:exportname=<export>]'' 2317 2318 2319Example for TCP 2320@example 2321qemu-system-i386 --drive file=nbd:192.0.2.1:30000 2322@end example 2323 2324Example for Unix Domain Sockets 2325@example 2326qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket 2327@end example 2328 2329@item SSH 2330QEMU supports SSH (Secure Shell) access to remote disks. 2331 2332Examples: 2333@example 2334qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img 2335qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img 2336@end example 2337 2338Currently authentication must be done using ssh-agent. Other 2339authentication methods may be supported in future. 2340 2341@item Sheepdog 2342Sheepdog is a distributed storage system for QEMU. 2343QEMU supports using either local sheepdog devices or remote networked 2344devices. 2345 2346Syntax for specifying a sheepdog device 2347@example 2348sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag] 2349@end example 2350 2351Example 2352@example 2353qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine 2354@end example 2355 2356See also @url{http://http://www.osrg.net/sheepdog/}. 2357 2358@item GlusterFS 2359GlusterFS is an user space distributed file system. 2360QEMU supports the use of GlusterFS volumes for hosting VM disk images using 2361TCP, Unix Domain Sockets and RDMA transport protocols. 2362 2363Syntax for specifying a VM disk image on GlusterFS volume is 2364@example 2365gluster[+transport]://[server[:port]]/volname/image[?socket=...] 2366@end example 2367 2368 2369Example 2370@example 2371qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img 2372@end example 2373 2374See also @url{http://www.gluster.org}. 2375 2376@item HTTP/HTTPS/FTP/FTPS/TFTP 2377QEMU supports read-only access to files accessed over http(s), ftp(s) and tftp. 2378 2379Syntax using a single filename: 2380@example 2381<protocol>://[<username>[:<password>]@@]<host>/<path> 2382@end example 2383 2384where: 2385@table @option 2386@item protocol 2387'http', 'https', 'ftp', 'ftps', or 'tftp'. 2388 2389@item username 2390Optional username for authentication to the remote server. 2391 2392@item password 2393Optional password for authentication to the remote server. 2394 2395@item host 2396Address of the remote server. 2397 2398@item path 2399Path on the remote server, including any query string. 2400@end table 2401 2402The following options are also supported: 2403@table @option 2404@item url 2405The full URL when passing options to the driver explicitly. 2406 2407@item readahead 2408The amount of data to read ahead with each range request to the remote server. 2409This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it 2410does not have a suffix, it will be assumed to be in bytes. The value must be a 2411multiple of 512 bytes. It defaults to 256k. 2412 2413@item sslverify 2414Whether to verify the remote server's certificate when connecting over SSL. It 2415can have the value 'on' or 'off'. It defaults to 'on'. 2416 2417@item cookie 2418Send this cookie (it can also be a list of cookies separated by ';') with 2419each outgoing request. Only supported when using protocols such as HTTP 2420which support cookies, otherwise ignored. 2421 2422@item timeout 2423Set the timeout in seconds of the CURL connection. This timeout is the time 2424that CURL waits for a response from the remote server to get the size of the 2425image to be downloaded. If not set, the default timeout of 5 seconds is used. 2426@end table 2427 2428Note that when passing options to qemu explicitly, @option{driver} is the value 2429of <protocol>. 2430 2431Example: boot from a remote Fedora 20 live ISO image 2432@example 2433qemu-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 2434 2435qemu-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 2436@end example 2437 2438Example: boot from a remote Fedora 20 cloud image using a local overlay for 2439writes, copy-on-read, and a readahead of 64k 2440@example 2441qemu-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 2442 2443qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on 2444@end example 2445 2446Example: boot from an image stored on a VMware vSphere server with a self-signed 2447certificate using a local overlay for writes, a readahead of 64k and a timeout 2448of 10 seconds. 2449@example 2450qemu-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 2451 2452qemu-system-x86_64 -drive file=/tmp/test.qcow2 2453@end example 2454ETEXI 2455 2456STEXI 2457@end table 2458ETEXI 2459 2460DEFHEADING(Bluetooth(R) options:) 2461STEXI 2462@table @option 2463ETEXI 2464 2465DEF("bt", HAS_ARG, QEMU_OPTION_bt, \ 2466 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \ 2467 "-bt hci,host[:id]\n" \ 2468 " use host's HCI with the given name\n" \ 2469 "-bt hci[,vlan=n]\n" \ 2470 " emulate a standard HCI in virtual scatternet 'n'\n" \ 2471 "-bt vhci[,vlan=n]\n" \ 2472 " add host computer to virtual scatternet 'n' using VHCI\n" \ 2473 "-bt device:dev[,vlan=n]\n" \ 2474 " emulate a bluetooth device 'dev' in scatternet 'n'\n", 2475 QEMU_ARCH_ALL) 2476STEXI 2477@item -bt hci[...] 2478@findex -bt 2479Defines the function of the corresponding Bluetooth HCI. -bt options 2480are matched with the HCIs present in the chosen machine type. For 2481example when emulating a machine with only one HCI built into it, only 2482the first @code{-bt hci[...]} option is valid and defines the HCI's 2483logic. The Transport Layer is decided by the machine type. Currently 2484the machines @code{n800} and @code{n810} have one HCI and all other 2485machines have none. 2486 2487@anchor{bt-hcis} 2488The following three types are recognized: 2489 2490@table @option 2491@item -bt hci,null 2492(default) The corresponding Bluetooth HCI assumes no internal logic 2493and will not respond to any HCI commands or emit events. 2494 2495@item -bt hci,host[:@var{id}] 2496(@code{bluez} only) The corresponding HCI passes commands / events 2497to / from the physical HCI identified by the name @var{id} (default: 2498@code{hci0}) on the computer running QEMU. Only available on @code{bluez} 2499capable systems like Linux. 2500 2501@item -bt hci[,vlan=@var{n}] 2502Add a virtual, standard HCI that will participate in the Bluetooth 2503scatternet @var{n} (default @code{0}). Similarly to @option{-net} 2504VLANs, devices inside a bluetooth network @var{n} can only communicate 2505with other devices in the same network (scatternet). 2506@end table 2507 2508@item -bt vhci[,vlan=@var{n}] 2509(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached 2510to the host bluetooth stack instead of to the emulated target. This 2511allows the host and target machines to participate in a common scatternet 2512and communicate. Requires the Linux @code{vhci} driver installed. Can 2513be used as following: 2514 2515@example 2516qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5 2517@end example 2518 2519@item -bt device:@var{dev}[,vlan=@var{n}] 2520Emulate a bluetooth device @var{dev} and place it in network @var{n} 2521(default @code{0}). QEMU can only emulate one type of bluetooth devices 2522currently: 2523 2524@table @option 2525@item keyboard 2526Virtual wireless keyboard implementing the HIDP bluetooth profile. 2527@end table 2528ETEXI 2529 2530STEXI 2531@end table 2532ETEXI 2533DEFHEADING() 2534 2535#ifdef CONFIG_TPM 2536DEFHEADING(TPM device options:) 2537 2538DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \ 2539 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n" 2540 " use path to provide path to a character device; default is /dev/tpm0\n" 2541 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n" 2542 " not provided it will be searched for in /sys/class/misc/tpm?/device\n", 2543 QEMU_ARCH_ALL) 2544STEXI 2545 2546The general form of a TPM device option is: 2547@table @option 2548 2549@item -tpmdev @var{backend} ,id=@var{id} [,@var{options}] 2550@findex -tpmdev 2551Backend type must be: 2552@option{passthrough}. 2553 2554The specific backend type will determine the applicable options. 2555The @code{-tpmdev} option creates the TPM backend and requires a 2556@code{-device} option that specifies the TPM frontend interface model. 2557 2558Options to each backend are described below. 2559 2560Use 'help' to print all available TPM backend types. 2561@example 2562qemu -tpmdev help 2563@end example 2564 2565@item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path} 2566 2567(Linux-host only) Enable access to the host's TPM using the passthrough 2568driver. 2569 2570@option{path} specifies the path to the host's TPM device, i.e., on 2571a Linux host this would be @code{/dev/tpm0}. 2572@option{path} is optional and by default @code{/dev/tpm0} is used. 2573 2574@option{cancel-path} specifies the path to the host TPM device's sysfs 2575entry allowing for cancellation of an ongoing TPM command. 2576@option{cancel-path} is optional and by default QEMU will search for the 2577sysfs entry to use. 2578 2579Some notes about using the host's TPM with the passthrough driver: 2580 2581The TPM device accessed by the passthrough driver must not be 2582used by any other application on the host. 2583 2584Since the host's firmware (BIOS/UEFI) has already initialized the TPM, 2585the VM's firmware (BIOS/UEFI) will not be able to initialize the 2586TPM again and may therefore not show a TPM-specific menu that would 2587otherwise allow the user to configure the TPM, e.g., allow the user to 2588enable/disable or activate/deactivate the TPM. 2589Further, if TPM ownership is released from within a VM then the host's TPM 2590will get disabled and deactivated. To enable and activate the 2591TPM again afterwards, the host has to be rebooted and the user is 2592required to enter the firmware's menu to enable and activate the TPM. 2593If the TPM is left disabled and/or deactivated most TPM commands will fail. 2594 2595To create a passthrough TPM use the following two options: 2596@example 2597-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0 2598@end example 2599Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by 2600@code{tpmdev=tpm0} in the device option. 2601 2602@end table 2603 2604ETEXI 2605 2606DEFHEADING() 2607 2608#endif 2609 2610DEFHEADING(Linux/Multiboot boot specific:) 2611STEXI 2612 2613When using these options, you can use a given Linux or Multiboot 2614kernel without installing it in the disk image. It can be useful 2615for easier testing of various kernels. 2616 2617@table @option 2618ETEXI 2619 2620DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \ 2621 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL) 2622STEXI 2623@item -kernel @var{bzImage} 2624@findex -kernel 2625Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel 2626or in multiboot format. 2627ETEXI 2628 2629DEF("append", HAS_ARG, QEMU_OPTION_append, \ 2630 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL) 2631STEXI 2632@item -append @var{cmdline} 2633@findex -append 2634Use @var{cmdline} as kernel command line 2635ETEXI 2636 2637DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \ 2638 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL) 2639STEXI 2640@item -initrd @var{file} 2641@findex -initrd 2642Use @var{file} as initial ram disk. 2643 2644@item -initrd "@var{file1} arg=foo,@var{file2}" 2645 2646This syntax is only available with multiboot. 2647 2648Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the 2649first module. 2650ETEXI 2651 2652DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \ 2653 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL) 2654STEXI 2655@item -dtb @var{file} 2656@findex -dtb 2657Use @var{file} as a device tree binary (dtb) image and pass it to the kernel 2658on boot. 2659ETEXI 2660 2661STEXI 2662@end table 2663ETEXI 2664DEFHEADING() 2665 2666DEFHEADING(Debug/Expert options:) 2667STEXI 2668@table @option 2669ETEXI 2670 2671DEF("serial", HAS_ARG, QEMU_OPTION_serial, \ 2672 "-serial dev redirect the serial port to char device 'dev'\n", 2673 QEMU_ARCH_ALL) 2674STEXI 2675@item -serial @var{dev} 2676@findex -serial 2677Redirect the virtual serial port to host character device 2678@var{dev}. The default device is @code{vc} in graphical mode and 2679@code{stdio} in non graphical mode. 2680 2681This option can be used several times to simulate up to 4 serial 2682ports. 2683 2684Use @code{-serial none} to disable all serial ports. 2685 2686Available character devices are: 2687@table @option 2688@item vc[:@var{W}x@var{H}] 2689Virtual console. Optionally, a width and height can be given in pixel with 2690@example 2691vc:800x600 2692@end example 2693It is also possible to specify width or height in characters: 2694@example 2695vc:80Cx24C 2696@end example 2697@item pty 2698[Linux only] Pseudo TTY (a new PTY is automatically allocated) 2699@item none 2700No device is allocated. 2701@item null 2702void device 2703@item chardev:@var{id} 2704Use a named character device defined with the @code{-chardev} option. 2705@item /dev/XXX 2706[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port 2707parameters are set according to the emulated ones. 2708@item /dev/parport@var{N} 2709[Linux only, parallel port only] Use host parallel port 2710@var{N}. Currently SPP and EPP parallel port features can be used. 2711@item file:@var{filename} 2712Write output to @var{filename}. No character can be read. 2713@item stdio 2714[Unix only] standard input/output 2715@item pipe:@var{filename} 2716name pipe @var{filename} 2717@item COM@var{n} 2718[Windows only] Use host serial port @var{n} 2719@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}] 2720This implements UDP Net Console. 2721When @var{remote_host} or @var{src_ip} are not specified 2722they default to @code{0.0.0.0}. 2723When not using a specified @var{src_port} a random port is automatically chosen. 2724 2725If you just want a simple readonly console you can use @code{netcat} or 2726@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as: 2727@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it 2728will appear in the netconsole session. 2729 2730If you plan to send characters back via netconsole or you want to stop 2731and start QEMU a lot of times, you should have QEMU use the same 2732source port each time by using something like @code{-serial 2733udp::4555@@:4556} to QEMU. Another approach is to use a patched 2734version of netcat which can listen to a TCP port and send and receive 2735characters via udp. If you have a patched version of netcat which 2736activates telnet remote echo and single char transfer, then you can 2737use the following options to step up a netcat redirector to allow 2738telnet on port 5555 to access the QEMU port. 2739@table @code 2740@item QEMU Options: 2741-serial udp::4555@@:4556 2742@item netcat options: 2743-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T 2744@item telnet options: 2745localhost 5555 2746@end table 2747 2748@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}] 2749The TCP Net Console has two modes of operation. It can send the serial 2750I/O to a location or wait for a connection from a location. By default 2751the TCP Net Console is sent to @var{host} at the @var{port}. If you use 2752the @var{server} option QEMU will wait for a client socket application 2753to connect to the port before continuing, unless the @code{nowait} 2754option was specified. The @code{nodelay} option disables the Nagle buffering 2755algorithm. The @code{reconnect} option only applies if @var{noserver} is 2756set, if the connection goes down it will attempt to reconnect at the 2757given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only 2758one TCP connection at a time is accepted. You can use @code{telnet} to 2759connect to the corresponding character device. 2760@table @code 2761@item Example to send tcp console to 192.168.0.2 port 4444 2762-serial tcp:192.168.0.2:4444 2763@item Example to listen and wait on port 4444 for connection 2764-serial tcp::4444,server 2765@item Example to not wait and listen on ip 192.168.0.100 port 4444 2766-serial tcp:192.168.0.100:4444,server,nowait 2767@end table 2768 2769@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay] 2770The telnet protocol is used instead of raw tcp sockets. The options 2771work the same as if you had specified @code{-serial tcp}. The 2772difference is that the port acts like a telnet server or client using 2773telnet option negotiation. This will also allow you to send the 2774MAGIC_SYSRQ sequence if you use a telnet that supports sending the break 2775sequence. Typically in unix telnet you do it with Control-] and then 2776type "send break" followed by pressing the enter key. 2777 2778@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}] 2779A unix domain socket is used instead of a tcp socket. The option works the 2780same as if you had specified @code{-serial tcp} except the unix domain socket 2781@var{path} is used for connections. 2782 2783@item mon:@var{dev_string} 2784This is a special option to allow the monitor to be multiplexed onto 2785another serial port. The monitor is accessed with key sequence of 2786@key{Control-a} and then pressing @key{c}. 2787@var{dev_string} should be any one of the serial devices specified 2788above. An example to multiplex the monitor onto a telnet server 2789listening on port 4444 would be: 2790@table @code 2791@item -serial mon:telnet::4444,server,nowait 2792@end table 2793When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate 2794QEMU any more but will be passed to the guest instead. 2795 2796@item braille 2797Braille device. This will use BrlAPI to display the braille output on a real 2798or fake device. 2799 2800@item msmouse 2801Three button serial mouse. Configure the guest to use Microsoft protocol. 2802@end table 2803ETEXI 2804 2805DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \ 2806 "-parallel dev redirect the parallel port to char device 'dev'\n", 2807 QEMU_ARCH_ALL) 2808STEXI 2809@item -parallel @var{dev} 2810@findex -parallel 2811Redirect the virtual parallel port to host device @var{dev} (same 2812devices as the serial port). On Linux hosts, @file{/dev/parportN} can 2813be used to use hardware devices connected on the corresponding host 2814parallel port. 2815 2816This option can be used several times to simulate up to 3 parallel 2817ports. 2818 2819Use @code{-parallel none} to disable all parallel ports. 2820ETEXI 2821 2822DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \ 2823 "-monitor dev redirect the monitor to char device 'dev'\n", 2824 QEMU_ARCH_ALL) 2825STEXI 2826@item -monitor @var{dev} 2827@findex -monitor 2828Redirect the monitor to host device @var{dev} (same devices as the 2829serial port). 2830The default device is @code{vc} in graphical mode and @code{stdio} in 2831non graphical mode. 2832Use @code{-monitor none} to disable the default monitor. 2833ETEXI 2834DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \ 2835 "-qmp dev like -monitor but opens in 'control' mode\n", 2836 QEMU_ARCH_ALL) 2837STEXI 2838@item -qmp @var{dev} 2839@findex -qmp 2840Like -monitor but opens in 'control' mode. 2841ETEXI 2842DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \ 2843 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n", 2844 QEMU_ARCH_ALL) 2845STEXI 2846@item -qmp-pretty @var{dev} 2847@findex -qmp-pretty 2848Like -qmp but uses pretty JSON formatting. 2849ETEXI 2850 2851DEF("mon", HAS_ARG, QEMU_OPTION_mon, \ 2852 "-mon [chardev=]name[,mode=readline|control][,default]\n", QEMU_ARCH_ALL) 2853STEXI 2854@item -mon [chardev=]name[,mode=readline|control][,default] 2855@findex -mon 2856Setup monitor on chardev @var{name}. 2857ETEXI 2858 2859DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ 2860 "-debugcon dev redirect the debug console to char device 'dev'\n", 2861 QEMU_ARCH_ALL) 2862STEXI 2863@item -debugcon @var{dev} 2864@findex -debugcon 2865Redirect the debug console to host device @var{dev} (same devices as the 2866serial port). The debug console is an I/O port which is typically port 28670xe9; writing to that I/O port sends output to this device. 2868The default device is @code{vc} in graphical mode and @code{stdio} in 2869non graphical mode. 2870ETEXI 2871 2872DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ 2873 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL) 2874STEXI 2875@item -pidfile @var{file} 2876@findex -pidfile 2877Store the QEMU process PID in @var{file}. It is useful if you launch QEMU 2878from a script. 2879ETEXI 2880 2881DEF("singlestep", 0, QEMU_OPTION_singlestep, \ 2882 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) 2883STEXI 2884@item -singlestep 2885@findex -singlestep 2886Run the emulation in single step mode. 2887ETEXI 2888 2889DEF("S", 0, QEMU_OPTION_S, \ 2890 "-S freeze CPU at startup (use 'c' to start execution)\n", 2891 QEMU_ARCH_ALL) 2892STEXI 2893@item -S 2894@findex -S 2895Do not start CPU at startup (you must type 'c' in the monitor). 2896ETEXI 2897 2898DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, 2899 "-realtime [mlock=on|off]\n" 2900 " run qemu with realtime features\n" 2901 " mlock=on|off controls mlock support (default: on)\n", 2902 QEMU_ARCH_ALL) 2903STEXI 2904@item -realtime mlock=on|off 2905@findex -realtime 2906Run qemu with realtime features. 2907mlocking qemu and guest memory can be enabled via @option{mlock=on} 2908(enabled by default). 2909ETEXI 2910 2911DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ 2912 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) 2913STEXI 2914@item -gdb @var{dev} 2915@findex -gdb 2916Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical 2917connections will likely be TCP-based, but also UDP, pseudo TTY, or even 2918stdio are reasonable use case. The latter is allowing to start QEMU from 2919within gdb and establish the connection via a pipe: 2920@example 2921(gdb) target remote | exec qemu-system-i386 -gdb stdio ... 2922@end example 2923ETEXI 2924 2925DEF("s", 0, QEMU_OPTION_s, \ 2926 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n", 2927 QEMU_ARCH_ALL) 2928STEXI 2929@item -s 2930@findex -s 2931Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234 2932(@pxref{gdb_usage}). 2933ETEXI 2934 2935DEF("d", HAS_ARG, QEMU_OPTION_d, \ 2936 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n", 2937 QEMU_ARCH_ALL) 2938STEXI 2939@item -d @var{item1}[,...] 2940@findex -d 2941Enable logging of specified items. Use '-d help' for a list of log items. 2942ETEXI 2943 2944DEF("D", HAS_ARG, QEMU_OPTION_D, \ 2945 "-D logfile output log to logfile (default stderr)\n", 2946 QEMU_ARCH_ALL) 2947STEXI 2948@item -D @var{logfile} 2949@findex -D 2950Output log in @var{logfile} instead of to stderr 2951ETEXI 2952 2953DEF("L", HAS_ARG, QEMU_OPTION_L, \ 2954 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", 2955 QEMU_ARCH_ALL) 2956STEXI 2957@item -L @var{path} 2958@findex -L 2959Set the directory for the BIOS, VGA BIOS and keymaps. 2960ETEXI 2961 2962DEF("bios", HAS_ARG, QEMU_OPTION_bios, \ 2963 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL) 2964STEXI 2965@item -bios @var{file} 2966@findex -bios 2967Set the filename for the BIOS. 2968ETEXI 2969 2970DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \ 2971 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL) 2972STEXI 2973@item -enable-kvm 2974@findex -enable-kvm 2975Enable KVM full virtualization support. This option is only available 2976if KVM support is enabled when compiling. 2977ETEXI 2978 2979DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, 2980 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) 2981DEF("xen-create", 0, QEMU_OPTION_xen_create, 2982 "-xen-create create domain using xen hypercalls, bypassing xend\n" 2983 " warning: should not be used when xend is in use\n", 2984 QEMU_ARCH_ALL) 2985DEF("xen-attach", 0, QEMU_OPTION_xen_attach, 2986 "-xen-attach attach to existing xen domain\n" 2987 " xend will use this when starting QEMU\n", 2988 QEMU_ARCH_ALL) 2989STEXI 2990@item -xen-domid @var{id} 2991@findex -xen-domid 2992Specify xen guest domain @var{id} (XEN only). 2993@item -xen-create 2994@findex -xen-create 2995Create domain using xen hypercalls, bypassing xend. 2996Warning: should not be used when xend is in use (XEN only). 2997@item -xen-attach 2998@findex -xen-attach 2999Attach to existing xen domain. 3000xend will use this when starting QEMU (XEN only). 3001ETEXI 3002 3003DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \ 3004 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL) 3005STEXI 3006@item -no-reboot 3007@findex -no-reboot 3008Exit instead of rebooting. 3009ETEXI 3010 3011DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \ 3012 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL) 3013STEXI 3014@item -no-shutdown 3015@findex -no-shutdown 3016Don't exit QEMU on guest shutdown, but instead only stop the emulation. 3017This allows for instance switching to monitor to commit changes to the 3018disk image. 3019ETEXI 3020 3021DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ 3022 "-loadvm [tag|id]\n" \ 3023 " start right away with a saved state (loadvm in monitor)\n", 3024 QEMU_ARCH_ALL) 3025STEXI 3026@item -loadvm @var{file} 3027@findex -loadvm 3028Start right away with a saved state (@code{loadvm} in monitor) 3029ETEXI 3030 3031#ifndef _WIN32 3032DEF("daemonize", 0, QEMU_OPTION_daemonize, \ 3033 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) 3034#endif 3035STEXI 3036@item -daemonize 3037@findex -daemonize 3038Daemonize the QEMU process after initialization. QEMU will not detach from 3039standard IO until it is ready to receive connections on any of its devices. 3040This option is a useful way for external programs to launch QEMU without having 3041to cope with initialization race conditions. 3042ETEXI 3043 3044DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \ 3045 "-option-rom rom load a file, rom, into the option ROM space\n", 3046 QEMU_ARCH_ALL) 3047STEXI 3048@item -option-rom @var{file} 3049@findex -option-rom 3050Load the contents of @var{file} as an option ROM. 3051This option is useful to load things like EtherBoot. 3052ETEXI 3053 3054HXCOMM Silently ignored for compatibility 3055DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL) 3056 3057HXCOMM Options deprecated by -rtc 3058DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL) 3059DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL) 3060 3061DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \ 3062 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \ 3063 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n", 3064 QEMU_ARCH_ALL) 3065 3066STEXI 3067 3068@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew] 3069@findex -rtc 3070Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current 3071UTC or local time, respectively. @code{localtime} is required for correct date in 3072MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the 3073format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC. 3074 3075By default the RTC is driven by the host system time. This allows using of the 3076RTC as accurate reference clock inside the guest, specifically if the host 3077time is smoothly following an accurate external reference clock, e.g. via NTP. 3078If you want to isolate the guest time from the host, you can set @option{clock} 3079to @code{rt} instead. To even prevent it from progressing during suspension, 3080you can set it to @code{vm}. 3081 3082Enable @option{driftfix} (i386 targets only) if you experience time drift problems, 3083specifically with Windows' ACPI HAL. This option will try to figure out how 3084many timer interrupts were not processed by the Windows guest and will 3085re-inject them. 3086ETEXI 3087 3088DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ 3089 "-icount [shift=N|auto][,align=on|off]\n" \ 3090 " enable virtual instruction counter with 2^N clock ticks per\n" \ 3091 " instruction and enable aligning the host and virtual clocks\n", QEMU_ARCH_ALL) 3092STEXI 3093@item -icount [shift=@var{N}|auto] 3094@findex -icount 3095Enable virtual instruction counter. The virtual cpu will execute one 3096instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified 3097then the virtual cpu speed will be automatically adjusted to keep virtual 3098time within a few seconds of real time. 3099 3100Note that while this option can give deterministic behavior, it does not 3101provide cycle accurate emulation. Modern CPUs contain superscalar out of 3102order cores with complex cache hierarchies. The number of instructions 3103executed often has little or no correlation with actual performance. 3104 3105@option{align=on} will activate the delay algorithm which will try to 3106to synchronise the host clock and the virtual clock. The goal is to 3107have a guest running at the real frequency imposed by the shift option. 3108Whenever the guest clock is behind the host clock and if 3109@option{align=on} is specified then we print a message to the user 3110to inform about the delay. 3111Currently this option does not work when @option{shift} is @code{auto}. 3112Note: The sync algorithm will work for those shift values for which 3113the guest clock runs ahead of the host clock. Typically this happens 3114when the shift value is high (how high depends on the host machine). 3115ETEXI 3116 3117DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ 3118 "-watchdog i6300esb|ib700\n" \ 3119 " enable virtual hardware watchdog [default=none]\n", 3120 QEMU_ARCH_ALL) 3121STEXI 3122@item -watchdog @var{model} 3123@findex -watchdog 3124Create a virtual hardware watchdog device. Once enabled (by a guest 3125action), the watchdog must be periodically polled by an agent inside 3126the guest or else the guest will be restarted. 3127 3128The @var{model} is the model of hardware watchdog to emulate. Choices 3129for model are: @code{ib700} (iBASE 700) which is a very simple ISA 3130watchdog with a single timer, or @code{i6300esb} (Intel 6300ESB I/O 3131controller hub) which is a much more featureful PCI-based dual-timer 3132watchdog. Choose a model for which your guest has drivers. 3133 3134Use @code{-watchdog help} to list available hardware models. Only one 3135watchdog can be enabled for a guest. 3136ETEXI 3137 3138DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \ 3139 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \ 3140 " action when watchdog fires [default=reset]\n", 3141 QEMU_ARCH_ALL) 3142STEXI 3143@item -watchdog-action @var{action} 3144@findex -watchdog-action 3145 3146The @var{action} controls what QEMU will do when the watchdog timer 3147expires. 3148The default is 3149@code{reset} (forcefully reset the guest). 3150Other possible actions are: 3151@code{shutdown} (attempt to gracefully shutdown the guest), 3152@code{poweroff} (forcefully poweroff the guest), 3153@code{pause} (pause the guest), 3154@code{debug} (print a debug message and continue), or 3155@code{none} (do nothing). 3156 3157Note that the @code{shutdown} action requires that the guest responds 3158to ACPI signals, which it may not be able to do in the sort of 3159situations where the watchdog would have expired, and thus 3160@code{-watchdog-action shutdown} is not recommended for production use. 3161 3162Examples: 3163 3164@table @code 3165@item -watchdog i6300esb -watchdog-action pause 3166@item -watchdog ib700 3167@end table 3168ETEXI 3169 3170DEF("echr", HAS_ARG, QEMU_OPTION_echr, \ 3171 "-echr chr set terminal escape character instead of ctrl-a\n", 3172 QEMU_ARCH_ALL) 3173STEXI 3174 3175@item -echr @var{numeric_ascii_value} 3176@findex -echr 3177Change the escape character used for switching to the monitor when using 3178monitor and serial sharing. The default is @code{0x01} when using the 3179@code{-nographic} option. @code{0x01} is equal to pressing 3180@code{Control-a}. You can select a different character from the ascii 3181control keys where 1 through 26 map to Control-a through Control-z. For 3182instance you could use the either of the following to change the escape 3183character to Control-t. 3184@table @code 3185@item -echr 0x14 3186@item -echr 20 3187@end table 3188ETEXI 3189 3190DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \ 3191 "-virtioconsole c\n" \ 3192 " set virtio console\n", QEMU_ARCH_ALL) 3193STEXI 3194@item -virtioconsole @var{c} 3195@findex -virtioconsole 3196Set virtio console. 3197 3198This option is maintained for backward compatibility. 3199 3200Please use @code{-device virtconsole} for the new way of invocation. 3201ETEXI 3202 3203DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \ 3204 "-show-cursor show cursor\n", QEMU_ARCH_ALL) 3205STEXI 3206@item -show-cursor 3207@findex -show-cursor 3208Show cursor. 3209ETEXI 3210 3211DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \ 3212 "-tb-size n set TB size\n", QEMU_ARCH_ALL) 3213STEXI 3214@item -tb-size @var{n} 3215@findex -tb-size 3216Set TB size. 3217ETEXI 3218 3219DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \ 3220 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \ 3221 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \ 3222 "-incoming unix:socketpath\n" \ 3223 " prepare for incoming migration, listen on\n" \ 3224 " specified protocol and socket address\n" \ 3225 "-incoming fd:fd\n" \ 3226 "-incoming exec:cmdline\n" \ 3227 " accept incoming migration on given file descriptor\n" \ 3228 " or from given external command\n", 3229 QEMU_ARCH_ALL) 3230STEXI 3231@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6] 3232@item -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6] 3233@findex -incoming 3234Prepare for incoming migration, listen on a given tcp port. 3235 3236@item -incoming unix:@var{socketpath} 3237Prepare for incoming migration, listen on a given unix socket. 3238 3239@item -incoming fd:@var{fd} 3240Accept incoming migration from a given filedescriptor. 3241 3242@item -incoming exec:@var{cmdline} 3243Accept incoming migration as an output from specified external command. 3244ETEXI 3245 3246DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \ 3247 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL) 3248STEXI 3249@item -nodefaults 3250@findex -nodefaults 3251Don't create default devices. Normally, QEMU sets the default devices like serial 3252port, parallel port, virtual console, monitor device, VGA adapter, floppy and 3253CD-ROM drive and others. The @code{-nodefaults} option will disable all those 3254default devices. 3255ETEXI 3256 3257#ifndef _WIN32 3258DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \ 3259 "-chroot dir chroot to dir just before starting the VM\n", 3260 QEMU_ARCH_ALL) 3261#endif 3262STEXI 3263@item -chroot @var{dir} 3264@findex -chroot 3265Immediately before starting guest execution, chroot to the specified 3266directory. Especially useful in combination with -runas. 3267ETEXI 3268 3269#ifndef _WIN32 3270DEF("runas", HAS_ARG, QEMU_OPTION_runas, \ 3271 "-runas user change to user id user just before starting the VM\n", 3272 QEMU_ARCH_ALL) 3273#endif 3274STEXI 3275@item -runas @var{user} 3276@findex -runas 3277Immediately before starting guest execution, drop root privileges, switching 3278to the specified user. 3279ETEXI 3280 3281DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env, 3282 "-prom-env variable=value\n" 3283 " set OpenBIOS nvram variables\n", 3284 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 3285STEXI 3286@item -prom-env @var{variable}=@var{value} 3287@findex -prom-env 3288Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only). 3289ETEXI 3290DEF("semihosting", 0, QEMU_OPTION_semihosting, 3291 "-semihosting semihosting mode\n", 3292 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32) 3293STEXI 3294@item -semihosting 3295@findex -semihosting 3296Enable semihosting mode (ARM, M68K, Xtensa only). 3297ETEXI 3298DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config, 3299 "-semihosting-config [enable=on|off,]target=native|gdb|auto semihosting configuration\n", 3300QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32) 3301STEXI 3302@item -semihosting-config [enable=on|off,]target=native|gdb|auto 3303@findex -semihosting-config 3304Enable semihosting and define where the semihosting calls will be addressed, 3305to QEMU (@code{native}) or to GDB (@code{gdb}). The default is @code{auto}, which means 3306@code{gdb} during debug sessions and @code{native} otherwise (ARM, M68K, Xtensa only). 3307ETEXI 3308DEF("old-param", 0, QEMU_OPTION_old_param, 3309 "-old-param old param mode\n", QEMU_ARCH_ARM) 3310STEXI 3311@item -old-param 3312@findex -old-param (ARM) 3313Old param mode (ARM only). 3314ETEXI 3315 3316DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ 3317 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n", 3318 QEMU_ARCH_ALL) 3319STEXI 3320@item -sandbox @var{arg} 3321@findex -sandbox 3322Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will 3323disable it. The default is 'off'. 3324ETEXI 3325 3326DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, 3327 "-readconfig <file>\n", QEMU_ARCH_ALL) 3328STEXI 3329@item -readconfig @var{file} 3330@findex -readconfig 3331Read device configuration from @var{file}. This approach is useful when you want to spawn 3332QEMU process with many command line options but you don't want to exceed the command line 3333character limit. 3334ETEXI 3335DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig, 3336 "-writeconfig <file>\n" 3337 " read/write config file\n", QEMU_ARCH_ALL) 3338STEXI 3339@item -writeconfig @var{file} 3340@findex -writeconfig 3341Write device configuration to @var{file}. The @var{file} can be either filename to save 3342command line and device configuration into file or dash @code{-}) character to print the 3343output to stdout. This can be later used as input file for @code{-readconfig} option. 3344ETEXI 3345DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, 3346 "-nodefconfig\n" 3347 " do not load default config files at startup\n", 3348 QEMU_ARCH_ALL) 3349STEXI 3350@item -nodefconfig 3351@findex -nodefconfig 3352Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup. 3353The @code{-nodefconfig} option will prevent QEMU from loading any of those config files. 3354ETEXI 3355DEF("no-user-config", 0, QEMU_OPTION_nouserconfig, 3356 "-no-user-config\n" 3357 " do not load user-provided config files at startup\n", 3358 QEMU_ARCH_ALL) 3359STEXI 3360@item -no-user-config 3361@findex -no-user-config 3362The @code{-no-user-config} option makes QEMU not load any of the user-provided 3363config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config 3364files from @var{datadir}. 3365ETEXI 3366DEF("trace", HAS_ARG, QEMU_OPTION_trace, 3367 "-trace [events=<file>][,file=<file>]\n" 3368 " specify tracing options\n", 3369 QEMU_ARCH_ALL) 3370STEXI 3371HXCOMM This line is not accurate, as some sub-options are backend-specific but 3372HXCOMM HX does not support conditional compilation of text. 3373@item -trace [events=@var{file}][,file=@var{file}] 3374@findex -trace 3375 3376Specify tracing options. 3377 3378@table @option 3379@item events=@var{file} 3380Immediately enable events listed in @var{file}. 3381The file must contain one event name (as listed in the @var{trace-events} file) 3382per line. 3383This option is only available if QEMU has been compiled with 3384either @var{simple} or @var{stderr} tracing backend. 3385@item file=@var{file} 3386Log output traces to @var{file}. 3387 3388This option is only available if QEMU has been compiled with 3389the @var{simple} tracing backend. 3390@end table 3391ETEXI 3392 3393HXCOMM Internal use 3394DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL) 3395DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL) 3396 3397#ifdef __linux__ 3398DEF("enable-fips", 0, QEMU_OPTION_enablefips, 3399 "-enable-fips enable FIPS 140-2 compliance\n", 3400 QEMU_ARCH_ALL) 3401#endif 3402STEXI 3403@item -enable-fips 3404@findex -enable-fips 3405Enable FIPS 140-2 compliance mode. 3406ETEXI 3407 3408HXCOMM Deprecated by -machine accel=tcg property 3409DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386) 3410 3411HXCOMM Deprecated by kvm-pit driver properties 3412DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection, 3413 "", QEMU_ARCH_I386) 3414 3415HXCOMM Deprecated (ignored) 3416DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386) 3417 3418HXCOMM Deprecated by -machine kernel_irqchip=on|off property 3419DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386) 3420 3421HXCOMM Deprecated (ignored) 3422DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL) 3423 3424DEF("object", HAS_ARG, QEMU_OPTION_object, 3425 "-object TYPENAME[,PROP1=VALUE1,...]\n" 3426 " create an new object of type TYPENAME setting properties\n" 3427 " in the order they are specified. Note that the 'id'\n" 3428 " property must be set. These objects are placed in the\n" 3429 " '/objects' path.\n", 3430 QEMU_ARCH_ALL) 3431STEXI 3432@item -object @var{typename}[,@var{prop1}=@var{value1},...] 3433@findex -object 3434Create an new object of type @var{typename} setting properties 3435in the order they are specified. Note that the 'id' 3436property must be set. These objects are placed in the 3437'/objects' path. 3438ETEXI 3439 3440DEF("msg", HAS_ARG, QEMU_OPTION_msg, 3441 "-msg timestamp[=on|off]\n" 3442 " change the format of messages\n" 3443 " on|off controls leading timestamps (default:on)\n", 3444 QEMU_ARCH_ALL) 3445STEXI 3446@item -msg timestamp[=on|off] 3447@findex -msg 3448prepend a timestamp to each log message.(default:on) 3449ETEXI 3450 3451DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate, 3452 "-dump-vmstate <file>\n" 3453 " Output vmstate information in JSON format to file.\n" 3454 " Use the scripts/vmstate-static-checker.py file to\n" 3455 " check for possible regressions in migration code\n" 3456 " by comparing two such vmstate dumps.", 3457 QEMU_ARCH_ALL) 3458STEXI 3459@item -dump-vmstate @var{file} 3460@findex -dump-vmstate 3461Dump json-encoded vmstate information for current machine type to file 3462in @var{file} 3463ETEXI 3464 3465HXCOMM This is the last statement. Insert new options before this line! 3466STEXI 3467@end table 3468ETEXI 3469