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 " kvm_shadow_mem=size of KVM shadow MMU\n" 37 " dump-guest-core=on|off include guest memory in a core dump (default=on)\n" 38 " mem-merge=on|off controls memory merge support (default: on)\n" 39 " iommu=on|off controls emulated Intel IOMMU (VT-d) support (default=off)\n", 40 QEMU_ARCH_ALL) 41STEXI 42@item -machine [type=]@var{name}[,prop=@var{value}[,...]] 43@findex -machine 44Select the emulated machine by @var{name}. Use @code{-machine help} to list 45available machines. Supported machine properties are: 46@table @option 47@item accel=@var{accels1}[:@var{accels2}[:...]] 48This is used to enable an accelerator. Depending on the target architecture, 49kvm, xen, or tcg can be available. By default, tcg is used. If there is more 50than one accelerator specified, the next one is used if the previous one fails 51to initialize. 52@item kernel_irqchip=on|off 53Enables in-kernel irqchip support for the chosen accelerator when available. 54@item kvm_shadow_mem=size 55Defines the size of the KVM shadow MMU. 56@item dump-guest-core=on|off 57Include guest memory in a core dump. The default is on. 58@item mem-merge=on|off 59Enables or disables memory merge support. This feature, when supported by 60the host, de-duplicates identical memory pages among VMs instances 61(enabled by default). 62@item iommu=on|off 63Enables or disables emulated Intel IOMMU (VT-d) support. The default is off. 64@end table 65ETEXI 66 67HXCOMM Deprecated by -machine 68DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL) 69 70DEF("cpu", HAS_ARG, QEMU_OPTION_cpu, 71 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL) 72STEXI 73@item -cpu @var{model} 74@findex -cpu 75Select CPU model (@code{-cpu help} for list and additional feature selection) 76ETEXI 77 78DEF("smp", HAS_ARG, QEMU_OPTION_smp, 79 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n" 80 " set the number of CPUs to 'n' [default=1]\n" 81 " maxcpus= maximum number of total cpus, including\n" 82 " offline CPUs for hotplug, etc\n" 83 " cores= number of CPU cores on one socket\n" 84 " threads= number of threads on one CPU core\n" 85 " sockets= number of discrete sockets in the system\n", 86 QEMU_ARCH_ALL) 87STEXI 88@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}] 89@findex -smp 90Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255 91CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs 92to 4. 93For the PC target, the number of @var{cores} per socket, the number 94of @var{threads} per cores and the total number of @var{sockets} can be 95specified. Missing values will be computed. If any on the three values is 96given, the total number of CPUs @var{n} can be omitted. @var{maxcpus} 97specifies the maximum number of hotpluggable CPUs. 98ETEXI 99 100DEF("numa", HAS_ARG, QEMU_OPTION_numa, 101 "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n" 102 "-numa node[,memdev=id][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL) 103STEXI 104@item -numa node[,mem=@var{size}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}] 105@item -numa node[,memdev=@var{id}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}] 106@findex -numa 107Simulate a multi node NUMA system. If @samp{mem}, @samp{memdev} 108and @samp{cpus} are omitted, resources are split equally. Also, note 109that the -@option{numa} option doesn't allocate any of the specified 110resources. That is, it just assigns existing resources to NUMA nodes. This 111means that one still has to use the @option{-m}, @option{-smp} options 112to allocate RAM and VCPUs respectively, and possibly @option{-object} 113to specify the memory backend for the @samp{memdev} suboption. 114 115@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, if one 116node uses @samp{memdev}, all of them have to use it. 117ETEXI 118 119DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd, 120 "-add-fd fd=fd,set=set[,opaque=opaque]\n" 121 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL) 122STEXI 123@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}] 124@findex -add-fd 125 126Add a file descriptor to an fd set. Valid options are: 127 128@table @option 129@item fd=@var{fd} 130This option defines the file descriptor of which a duplicate is added to fd set. 131The file descriptor cannot be stdin, stdout, or stderr. 132@item set=@var{set} 133This option defines the ID of the fd set to add the file descriptor to. 134@item opaque=@var{opaque} 135This option defines a free-form string that can be used to describe @var{fd}. 136@end table 137 138You can open an image using pre-opened file descriptors from an fd set: 139@example 140qemu-system-i386 141-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 142-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 143-drive file=/dev/fdset/2,index=0,media=disk 144@end example 145ETEXI 146 147DEF("set", HAS_ARG, QEMU_OPTION_set, 148 "-set group.id.arg=value\n" 149 " set <arg> parameter for item <id> of type <group>\n" 150 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL) 151STEXI 152@item -set @var{group}.@var{id}.@var{arg}=@var{value} 153@findex -set 154Set parameter @var{arg} for item @var{id} of type @var{group}\n" 155ETEXI 156 157DEF("global", HAS_ARG, QEMU_OPTION_global, 158 "-global driver.prop=value\n" 159 " set a global default for a driver property\n", 160 QEMU_ARCH_ALL) 161STEXI 162@item -global @var{driver}.@var{prop}=@var{value} 163@findex -global 164Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.: 165 166@example 167qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk 168@end example 169 170In particular, you can use this to set driver properties for devices which are 171created automatically by the machine model. To create a device which is not 172created automatically and set properties on it, use -@option{device}. 173ETEXI 174 175DEF("boot", HAS_ARG, QEMU_OPTION_boot, 176 "-boot [order=drives][,once=drives][,menu=on|off]\n" 177 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n" 178 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n" 179 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n" 180 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n" 181 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n", 182 QEMU_ARCH_ALL) 183STEXI 184@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] 185@findex -boot 186Specify boot order @var{drives} as a string of drive letters. Valid 187drive letters depend on the target achitecture. The x86 PC uses: a, b 188(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot 189from network adapter 1-4), hard disk boot is the default. To apply a 190particular boot order only on the first startup, specify it via 191@option{once}. 192 193Interactive boot menus/prompts can be enabled via @option{menu=on} as far 194as firmware/BIOS supports them. The default is non-interactive boot. 195 196A splash picture could be passed to bios, enabling user to show it as logo, 197when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS 198supports them. Currently Seabios for X86 system support it. 199limitation: The splash file could be a jpeg file or a BMP file in 24 BPP 200format(true color). The resolution should be supported by the SVGA mode, so 201the recommended is 320x240, 640x480, 800x640. 202 203A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms 204when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not 205reboot, qemu passes '-1' to bios by default. Currently Seabios for X86 206system support it. 207 208Do strict boot via @option{strict=on} as far as firmware/BIOS 209supports it. This only effects when boot priority is changed by 210bootindex options. The default is non-strict boot. 211 212@example 213# try to boot from network first, then from hard disk 214qemu-system-i386 -boot order=nc 215# boot from CD-ROM first, switch back to default order after reboot 216qemu-system-i386 -boot once=d 217# boot with a splash picture for 5 seconds. 218qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000 219@end example 220 221Note: The legacy format '-boot @var{drives}' is still supported but its 222use is discouraged as it may be removed from future versions. 223ETEXI 224 225DEF("m", HAS_ARG, QEMU_OPTION_m, 226 "-m[emory] [size=]megs[,slots=n,maxmem=size]\n" 227 " configure guest RAM\n" 228 " size: initial amount of guest memory (default: " 229 stringify(DEFAULT_RAM_SIZE) "MiB)\n" 230 " slots: number of hotplug slots (default: none)\n" 231 " maxmem: maximum amount of guest memory (default: none)\n" 232 "NOTE: Some architectures might enforce a specific granularity\n", 233 QEMU_ARCH_ALL) 234STEXI 235@item -m [size=]@var{megs} 236@findex -m 237Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally, 238a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or 239gigabytes respectively. Optional pair @var{slots}, @var{maxmem} could be used 240to set amount of hotluggable memory slots and possible maximum amount of memory. 241ETEXI 242 243DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath, 244 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL) 245STEXI 246@item -mem-path @var{path} 247@findex -mem-path 248Allocate guest RAM from a temporarily created file in @var{path}. 249ETEXI 250 251DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc, 252 "-mem-prealloc preallocate guest memory (use with -mem-path)\n", 253 QEMU_ARCH_ALL) 254STEXI 255@item -mem-prealloc 256@findex -mem-prealloc 257Preallocate memory when using -mem-path. 258ETEXI 259 260DEF("k", HAS_ARG, QEMU_OPTION_k, 261 "-k language use keyboard layout (for example 'fr' for French)\n", 262 QEMU_ARCH_ALL) 263STEXI 264@item -k @var{language} 265@findex -k 266Use keyboard layout @var{language} (for example @code{fr} for 267French). This option is only needed where it is not easy to get raw PC 268keycodes (e.g. on Macs, with some X11 servers or with a VNC 269display). You don't normally need to use it on PC/Linux or PC/Windows 270hosts. 271 272The available layouts are: 273@example 274ar de-ch es fo fr-ca hu ja mk no pt-br sv 275da en-gb et fr fr-ch is lt nl pl ru th 276de en-us fi fr-be hr it lv nl-be pt sl tr 277@end example 278 279The default is @code{en-us}. 280ETEXI 281 282 283DEF("audio-help", 0, QEMU_OPTION_audio_help, 284 "-audio-help print list of audio drivers and their options\n", 285 QEMU_ARCH_ALL) 286STEXI 287@item -audio-help 288@findex -audio-help 289Will show the audio subsystem help: list of drivers, tunable 290parameters. 291ETEXI 292 293DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw, 294 "-soundhw c1,... enable audio support\n" 295 " and only specified sound cards (comma separated list)\n" 296 " use '-soundhw help' to get the list of supported cards\n" 297 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL) 298STEXI 299@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all 300@findex -soundhw 301Enable audio and selected sound hardware. Use 'help' to print all 302available sound hardware. 303 304@example 305qemu-system-i386 -soundhw sb16,adlib disk.img 306qemu-system-i386 -soundhw es1370 disk.img 307qemu-system-i386 -soundhw ac97 disk.img 308qemu-system-i386 -soundhw hda disk.img 309qemu-system-i386 -soundhw all disk.img 310qemu-system-i386 -soundhw help 311@end example 312 313Note that Linux's i810_audio OSS kernel (for AC97) module might 314require manually specifying clocking. 315 316@example 317modprobe i810_audio clocking=48000 318@end example 319ETEXI 320 321DEF("balloon", HAS_ARG, QEMU_OPTION_balloon, 322 "-balloon none disable balloon device\n" 323 "-balloon virtio[,addr=str]\n" 324 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL) 325STEXI 326@item -balloon none 327@findex -balloon 328Disable balloon device. 329@item -balloon virtio[,addr=@var{addr}] 330Enable virtio balloon device (default), optionally with PCI address 331@var{addr}. 332ETEXI 333 334DEF("device", HAS_ARG, QEMU_OPTION_device, 335 "-device driver[,prop[=value][,...]]\n" 336 " add device (based on driver)\n" 337 " prop=value,... sets driver properties\n" 338 " use '-device help' to print all possible drivers\n" 339 " use '-device driver,help' to print all possible properties\n", 340 QEMU_ARCH_ALL) 341STEXI 342@item -device @var{driver}[,@var{prop}[=@var{value}][,...]] 343@findex -device 344Add device @var{driver}. @var{prop}=@var{value} sets driver 345properties. Valid properties depend on the driver. To get help on 346possible drivers and properties, use @code{-device help} and 347@code{-device @var{driver},help}. 348ETEXI 349 350DEF("name", HAS_ARG, QEMU_OPTION_name, 351 "-name string1[,process=string2][,debug-threads=on|off]\n" 352 " set the name of the guest\n" 353 " string1 sets the window title and string2 the process name (on Linux)\n" 354 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n" 355 " NOTE: The thread names are for debugging and not a stable API.\n", 356 QEMU_ARCH_ALL) 357STEXI 358@item -name @var{name} 359@findex -name 360Sets the @var{name} of the guest. 361This name will be displayed in the SDL window caption. 362The @var{name} will also be used for the VNC server. 363Also optionally set the top visible process name in Linux. 364Naming of individual threads can also be enabled on Linux to aid debugging. 365ETEXI 366 367DEF("uuid", HAS_ARG, QEMU_OPTION_uuid, 368 "-uuid %08x-%04x-%04x-%04x-%012x\n" 369 " specify machine UUID\n", QEMU_ARCH_ALL) 370STEXI 371@item -uuid @var{uuid} 372@findex -uuid 373Set system UUID. 374ETEXI 375 376STEXI 377@end table 378ETEXI 379DEFHEADING() 380 381DEFHEADING(Block device options:) 382STEXI 383@table @option 384ETEXI 385 386DEF("fda", HAS_ARG, QEMU_OPTION_fda, 387 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL) 388DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL) 389STEXI 390@item -fda @var{file} 391@item -fdb @var{file} 392@findex -fda 393@findex -fdb 394Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can 395use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}). 396ETEXI 397 398DEF("hda", HAS_ARG, QEMU_OPTION_hda, 399 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL) 400DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL) 401DEF("hdc", HAS_ARG, QEMU_OPTION_hdc, 402 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL) 403DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL) 404STEXI 405@item -hda @var{file} 406@item -hdb @var{file} 407@item -hdc @var{file} 408@item -hdd @var{file} 409@findex -hda 410@findex -hdb 411@findex -hdc 412@findex -hdd 413Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}). 414ETEXI 415 416DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom, 417 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n", 418 QEMU_ARCH_ALL) 419STEXI 420@item -cdrom @var{file} 421@findex -cdrom 422Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and 423@option{-cdrom} at the same time). You can use the host CD-ROM by 424using @file{/dev/cdrom} as filename (@pxref{host_drives}). 425ETEXI 426 427DEF("drive", HAS_ARG, QEMU_OPTION_drive, 428 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" 429 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n" 430 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n" 431 " [,serial=s][,addr=A][,rerror=ignore|stop|report]\n" 432 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n" 433 " [,readonly=on|off][,copy-on-read=on|off]\n" 434 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n" 435 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n" 436 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n" 437 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n" 438 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n" 439 " [[,iops_size=is]]\n" 440 " use 'file' as a drive image\n", QEMU_ARCH_ALL) 441STEXI 442@item -drive @var{option}[,@var{option}[,@var{option}[,...]]] 443@findex -drive 444 445Define a new drive. Valid options are: 446 447@table @option 448@item file=@var{file} 449This option defines which disk image (@pxref{disk_images}) to use with 450this drive. If the filename contains comma, you must double it 451(for instance, "file=my,,file" to use file "my,file"). 452 453Special files such as iSCSI devices can be specified using protocol 454specific URLs. See the section for "Device URL Syntax" for more information. 455@item if=@var{interface} 456This option defines on which type on interface the drive is connected. 457Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio. 458@item bus=@var{bus},unit=@var{unit} 459These options define where is connected the drive by defining the bus number and 460the unit id. 461@item index=@var{index} 462This option defines where is connected the drive by using an index in the list 463of available connectors of a given interface type. 464@item media=@var{media} 465This option defines the type of the media: disk or cdrom. 466@item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}] 467These options have the same definition as they have in @option{-hdachs}. 468@item snapshot=@var{snapshot} 469@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive 470(see @option{-snapshot}). 471@item cache=@var{cache} 472@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data. 473@item aio=@var{aio} 474@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO. 475@item discard=@var{discard} 476@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. 477@item format=@var{format} 478Specify which disk @var{format} will be used rather than detecting 479the format. Can be used to specifiy format=raw to avoid interpreting 480an untrusted format header. 481@item serial=@var{serial} 482This option specifies the serial number to assign to the device. 483@item addr=@var{addr} 484Specify the controller's PCI address (if=virtio only). 485@item werror=@var{action},rerror=@var{action} 486Specify which @var{action} to take on write and read errors. Valid actions are: 487"ignore" (ignore the error and try to continue), "stop" (pause QEMU), 488"report" (report the error to the guest), "enospc" (pause QEMU only if the 489host disk is full; report the error to the guest otherwise). 490The default setting is @option{werror=enospc} and @option{rerror=report}. 491@item readonly 492Open drive @option{file} as read-only. Guest write attempts will fail. 493@item copy-on-read=@var{copy-on-read} 494@var{copy-on-read} is "on" or "off" and enables whether to copy read backing 495file sectors into the image file. 496@item detect-zeroes=@var{detect-zeroes} 497@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic 498conversion of plain zero writes by the OS to driver specific optimized 499zero write commands. You may even choose "unmap" if @var{discard} is set 500to "unmap" to allow a zero write to be converted to an UNMAP operation. 501@end table 502 503By default, the @option{cache=writeback} mode is used. It will report data 504writes as completed as soon as the data is present in the host page cache. 505This is safe as long as your guest OS makes sure to correctly flush disk caches 506where needed. If your guest OS does not handle volatile disk write caches 507correctly and your host crashes or loses power, then the guest may experience 508data corruption. 509 510For such guests, you should consider using @option{cache=writethrough}. This 511means that the host page cache will be used to read and write data, but write 512notification will be sent to the guest only after QEMU has made sure to flush 513each write to the disk. Be aware that this has a major impact on performance. 514 515The host page cache can be avoided entirely with @option{cache=none}. This will 516attempt to do disk IO directly to the guest's memory. QEMU may still perform 517an internal copy of the data. Note that this is considered a writeback mode and 518the guest OS must handle the disk write cache correctly in order to avoid data 519corruption on host crashes. 520 521The host page cache can be avoided while only sending write notifications to 522the guest when the data has been flushed to the disk using 523@option{cache=directsync}. 524 525In case you don't care about data integrity over host failures, use 526@option{cache=unsafe}. This option tells QEMU that it never needs to write any 527data to the disk but can instead keep things in cache. If anything goes wrong, 528like your host losing power, the disk storage getting disconnected accidentally, 529etc. your image will most probably be rendered unusable. When using 530the @option{-snapshot} option, unsafe caching is always used. 531 532Copy-on-read avoids accessing the same backing file sectors repeatedly and is 533useful when the backing file is over a slow network. By default copy-on-read 534is off. 535 536Instead of @option{-cdrom} you can use: 537@example 538qemu-system-i386 -drive file=file,index=2,media=cdrom 539@end example 540 541Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can 542use: 543@example 544qemu-system-i386 -drive file=file,index=0,media=disk 545qemu-system-i386 -drive file=file,index=1,media=disk 546qemu-system-i386 -drive file=file,index=2,media=disk 547qemu-system-i386 -drive file=file,index=3,media=disk 548@end example 549 550You can open an image using pre-opened file descriptors from an fd set: 551@example 552qemu-system-i386 553-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 554-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 555-drive file=/dev/fdset/2,index=0,media=disk 556@end example 557 558You can connect a CDROM to the slave of ide0: 559@example 560qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom 561@end example 562 563If you don't specify the "file=" argument, you define an empty drive: 564@example 565qemu-system-i386 -drive if=ide,index=1,media=cdrom 566@end example 567 568You can connect a SCSI disk with unit ID 6 on the bus #0: 569@example 570qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6 571@end example 572 573Instead of @option{-fda}, @option{-fdb}, you can use: 574@example 575qemu-system-i386 -drive file=file,index=0,if=floppy 576qemu-system-i386 -drive file=file,index=1,if=floppy 577@end example 578 579By default, @var{interface} is "ide" and @var{index} is automatically 580incremented: 581@example 582qemu-system-i386 -drive file=a -drive file=b" 583@end example 584is interpreted like: 585@example 586qemu-system-i386 -hda a -hdb b 587@end example 588ETEXI 589 590DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock, 591 "-mtdblock file use 'file' as on-board Flash memory image\n", 592 QEMU_ARCH_ALL) 593STEXI 594@item -mtdblock @var{file} 595@findex -mtdblock 596Use @var{file} as on-board Flash memory image. 597ETEXI 598 599DEF("sd", HAS_ARG, QEMU_OPTION_sd, 600 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL) 601STEXI 602@item -sd @var{file} 603@findex -sd 604Use @var{file} as SecureDigital card image. 605ETEXI 606 607DEF("pflash", HAS_ARG, QEMU_OPTION_pflash, 608 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL) 609STEXI 610@item -pflash @var{file} 611@findex -pflash 612Use @var{file} as a parallel flash image. 613ETEXI 614 615DEF("snapshot", 0, QEMU_OPTION_snapshot, 616 "-snapshot write to temporary files instead of disk image files\n", 617 QEMU_ARCH_ALL) 618STEXI 619@item -snapshot 620@findex -snapshot 621Write to temporary files instead of disk image files. In this case, 622the raw disk image you use is not written back. You can however force 623the write back by pressing @key{C-a s} (@pxref{disk_images}). 624ETEXI 625 626DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \ 627 "-hdachs c,h,s[,t]\n" \ 628 " force hard disk 0 physical geometry and the optional BIOS\n" \ 629 " translation (t=none or lba) (usually QEMU can guess them)\n", 630 QEMU_ARCH_ALL) 631STEXI 632@item -hdachs @var{c},@var{h},@var{s},[,@var{t}] 633@findex -hdachs 634Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <= 635@var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS 636translation mode (@var{t}=none, lba or auto). Usually QEMU can guess 637all those parameters. This option is useful for old MS-DOS disk 638images. 639ETEXI 640 641DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev, 642 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n" 643 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n", 644 QEMU_ARCH_ALL) 645 646STEXI 647 648@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}] 649@findex -fsdev 650Define a new file system device. Valid options are: 651@table @option 652@item @var{fsdriver} 653This option specifies the fs driver backend to use. 654Currently "local", "handle" and "proxy" file system drivers are supported. 655@item id=@var{id} 656Specifies identifier for this device 657@item path=@var{path} 658Specifies the export path for the file system device. Files under 659this path will be available to the 9p client on the guest. 660@item security_model=@var{security_model} 661Specifies the security model to be used for this export path. 662Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 663In "passthrough" security model, files are stored using the same 664credentials as they are created on the guest. This requires QEMU 665to run as root. In "mapped-xattr" security model, some of the file 666attributes like uid, gid, mode bits and link target are stored as 667file attributes. For "mapped-file" these attributes are stored in the 668hidden .virtfs_metadata directory. Directories exported by this security model cannot 669interact with other unix tools. "none" security model is same as 670passthrough except the sever won't report failures if it fails to 671set file attributes like ownership. Security model is mandatory 672only for local fsdriver. Other fsdrivers (like handle, proxy) don't take 673security model as a parameter. 674@item writeout=@var{writeout} 675This is an optional argument. The only supported value is "immediate". 676This means that host page cache will be used to read and write data but 677write notification will be sent to the guest only when the data has been 678reported as written by the storage subsystem. 679@item readonly 680Enables exporting 9p share as a readonly mount for guests. By default 681read-write access is given. 682@item socket=@var{socket} 683Enables proxy filesystem driver to use passed socket file for communicating 684with virtfs-proxy-helper 685@item sock_fd=@var{sock_fd} 686Enables proxy filesystem driver to use passed socket descriptor for 687communicating with virtfs-proxy-helper. Usually a helper like libvirt 688will create socketpair and pass one of the fds as sock_fd 689@end table 690 691-fsdev option is used along with -device driver "virtio-9p-pci". 692@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag} 693Options for virtio-9p-pci driver are: 694@table @option 695@item fsdev=@var{id} 696Specifies the id value specified along with -fsdev option 697@item mount_tag=@var{mount_tag} 698Specifies the tag name to be used by the guest to mount this export point 699@end table 700 701ETEXI 702 703DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs, 704 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n" 705 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n", 706 QEMU_ARCH_ALL) 707 708STEXI 709 710@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}] 711@findex -virtfs 712 713The general form of a Virtual File system pass-through options are: 714@table @option 715@item @var{fsdriver} 716This option specifies the fs driver backend to use. 717Currently "local", "handle" and "proxy" file system drivers are supported. 718@item id=@var{id} 719Specifies identifier for this device 720@item path=@var{path} 721Specifies the export path for the file system device. Files under 722this path will be available to the 9p client on the guest. 723@item security_model=@var{security_model} 724Specifies the security model to be used for this export path. 725Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 726In "passthrough" security model, files are stored using the same 727credentials as they are created on the guest. This requires QEMU 728to run as root. In "mapped-xattr" security model, some of the file 729attributes like uid, gid, mode bits and link target are stored as 730file attributes. For "mapped-file" these attributes are stored in the 731hidden .virtfs_metadata directory. Directories exported by this security model cannot 732interact with other unix tools. "none" security model is same as 733passthrough except the sever won't report failures if it fails to 734set file attributes like ownership. Security model is mandatory only 735for local fsdriver. Other fsdrivers (like handle, proxy) don't take security 736model as a parameter. 737@item writeout=@var{writeout} 738This is an optional argument. The only supported value is "immediate". 739This means that host page cache will be used to read and write data but 740write notification will be sent to the guest only when the data has been 741reported as written by the storage subsystem. 742@item readonly 743Enables exporting 9p share as a readonly mount for guests. By default 744read-write access is given. 745@item socket=@var{socket} 746Enables proxy filesystem driver to use passed socket file for 747communicating with virtfs-proxy-helper. Usually a helper like libvirt 748will create socketpair and pass one of the fds as sock_fd 749@item sock_fd 750Enables proxy filesystem driver to use passed 'sock_fd' as the socket 751descriptor for interfacing with virtfs-proxy-helper 752@end table 753ETEXI 754 755DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth, 756 "-virtfs_synth Create synthetic file system image\n", 757 QEMU_ARCH_ALL) 758STEXI 759@item -virtfs_synth 760@findex -virtfs_synth 761Create synthetic file system image 762ETEXI 763 764STEXI 765@end table 766ETEXI 767DEFHEADING() 768 769DEFHEADING(USB options:) 770STEXI 771@table @option 772ETEXI 773 774DEF("usb", 0, QEMU_OPTION_usb, 775 "-usb enable the USB driver (will be the default soon)\n", 776 QEMU_ARCH_ALL) 777STEXI 778@item -usb 779@findex -usb 780Enable the USB driver (will be the default soon) 781ETEXI 782 783DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice, 784 "-usbdevice name add the host or guest USB device 'name'\n", 785 QEMU_ARCH_ALL) 786STEXI 787 788@item -usbdevice @var{devname} 789@findex -usbdevice 790Add the USB device @var{devname}. @xref{usb_devices}. 791 792@table @option 793 794@item mouse 795Virtual Mouse. This will override the PS/2 mouse emulation when activated. 796 797@item tablet 798Pointer device that uses absolute coordinates (like a touchscreen). This 799means QEMU is able to report the mouse position without having to grab the 800mouse. Also overrides the PS/2 mouse emulation when activated. 801 802@item disk:[format=@var{format}]:@var{file} 803Mass storage device based on file. The optional @var{format} argument 804will be used rather than detecting the format. Can be used to specifiy 805@code{format=raw} to avoid interpreting an untrusted format header. 806 807@item host:@var{bus}.@var{addr} 808Pass through the host device identified by @var{bus}.@var{addr} (Linux only). 809 810@item host:@var{vendor_id}:@var{product_id} 811Pass through the host device identified by @var{vendor_id}:@var{product_id} 812(Linux only). 813 814@item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev} 815Serial converter to host character device @var{dev}, see @code{-serial} for the 816available devices. 817 818@item braille 819Braille device. This will use BrlAPI to display the braille output on a real 820or fake device. 821 822@item net:@var{options} 823Network adapter that supports CDC ethernet and RNDIS protocols. 824 825@end table 826ETEXI 827 828STEXI 829@end table 830ETEXI 831DEFHEADING() 832 833DEFHEADING(Display options:) 834STEXI 835@table @option 836ETEXI 837 838DEF("display", HAS_ARG, QEMU_OPTION_display, 839 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n" 840 " [,window_close=on|off]|curses|none|\n" 841 " gtk[,grab_on_hover=on|off]|\n" 842 " vnc=<display>[,<optargs>]\n" 843 " select display type\n", QEMU_ARCH_ALL) 844STEXI 845@item -display @var{type} 846@findex -display 847Select type of display to use. This option is a replacement for the 848old style -sdl/-curses/... options. Valid values for @var{type} are 849@table @option 850@item sdl 851Display video output via SDL (usually in a separate graphics 852window; see the SDL documentation for other possibilities). 853@item curses 854Display video output via curses. For graphics device models which 855support a text mode, QEMU can display this output using a 856curses/ncurses interface. Nothing is displayed when the graphics 857device is in graphical mode or if the graphics device does not support 858a text mode. Generally only the VGA device models support text mode. 859@item none 860Do not display video output. The guest will still see an emulated 861graphics card, but its output will not be displayed to the QEMU 862user. This option differs from the -nographic option in that it 863only affects what is done with video output; -nographic also changes 864the destination of the serial and parallel port data. 865@item gtk 866Display video output in a GTK window. This interface provides drop-down 867menus and other UI elements to configure and control the VM during 868runtime. 869@item vnc 870Start a VNC server on display <arg> 871@end table 872ETEXI 873 874DEF("nographic", 0, QEMU_OPTION_nographic, 875 "-nographic disable graphical output and redirect serial I/Os to console\n", 876 QEMU_ARCH_ALL) 877STEXI 878@item -nographic 879@findex -nographic 880Normally, QEMU uses SDL to display the VGA output. With this option, 881you can totally disable graphical output so that QEMU is a simple 882command line application. The emulated serial port is redirected on 883the console and muxed with the monitor (unless redirected elsewhere 884explicitly). Therefore, you can still use QEMU to debug a Linux kernel 885with a serial console. Use @key{C-a h} for help on switching between 886the console and monitor. 887ETEXI 888 889DEF("curses", 0, QEMU_OPTION_curses, 890 "-curses use a curses/ncurses interface instead of SDL\n", 891 QEMU_ARCH_ALL) 892STEXI 893@item -curses 894@findex -curses 895Normally, QEMU uses SDL to display the VGA output. With this option, 896QEMU can display the VGA output when in text mode using a 897curses/ncurses interface. Nothing is displayed in graphical mode. 898ETEXI 899 900DEF("no-frame", 0, QEMU_OPTION_no_frame, 901 "-no-frame open SDL window without a frame and window decorations\n", 902 QEMU_ARCH_ALL) 903STEXI 904@item -no-frame 905@findex -no-frame 906Do not use decorations for SDL windows and start them using the whole 907available screen space. This makes the using QEMU in a dedicated desktop 908workspace more convenient. 909ETEXI 910 911DEF("alt-grab", 0, QEMU_OPTION_alt_grab, 912 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n", 913 QEMU_ARCH_ALL) 914STEXI 915@item -alt-grab 916@findex -alt-grab 917Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also 918affects the special keys (for fullscreen, monitor-mode switching, etc). 919ETEXI 920 921DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab, 922 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n", 923 QEMU_ARCH_ALL) 924STEXI 925@item -ctrl-grab 926@findex -ctrl-grab 927Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also 928affects the special keys (for fullscreen, monitor-mode switching, etc). 929ETEXI 930 931DEF("no-quit", 0, QEMU_OPTION_no_quit, 932 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL) 933STEXI 934@item -no-quit 935@findex -no-quit 936Disable SDL window close capability. 937ETEXI 938 939DEF("sdl", 0, QEMU_OPTION_sdl, 940 "-sdl enable SDL\n", QEMU_ARCH_ALL) 941STEXI 942@item -sdl 943@findex -sdl 944Enable SDL. 945ETEXI 946 947DEF("spice", HAS_ARG, QEMU_OPTION_spice, 948 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n" 949 " [,x509-key-file=<file>][,x509-key-password=<file>]\n" 950 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n" 951 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6]\n" 952 " [,tls-ciphers=<list>]\n" 953 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n" 954 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n" 955 " [,sasl][,password=<secret>][,disable-ticketing]\n" 956 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n" 957 " [,jpeg-wan-compression=[auto|never|always]]\n" 958 " [,zlib-glz-wan-compression=[auto|never|always]]\n" 959 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n" 960 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n" 961 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n" 962 " enable spice\n" 963 " at least one of {port, tls-port} is mandatory\n", 964 QEMU_ARCH_ALL) 965STEXI 966@item -spice @var{option}[,@var{option}[,...]] 967@findex -spice 968Enable the spice remote desktop protocol. Valid options are 969 970@table @option 971 972@item port=<nr> 973Set the TCP port spice is listening on for plaintext channels. 974 975@item addr=<addr> 976Set the IP address spice is listening on. Default is any address. 977 978@item ipv4 979@item ipv6 980Force using the specified IP version. 981 982@item password=<secret> 983Set the password you need to authenticate. 984 985@item sasl 986Require that the client use SASL to authenticate with the spice. 987The exact choice of authentication method used is controlled from the 988system / user's SASL configuration file for the 'qemu' service. This 989is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 990unprivileged user, an environment variable SASL_CONF_PATH can be used 991to make it search alternate locations for the service config. 992While some SASL auth methods can also provide data encryption (eg GSSAPI), 993it is recommended that SASL always be combined with the 'tls' and 994'x509' settings to enable use of SSL and server certificates. This 995ensures a data encryption preventing compromise of authentication 996credentials. 997 998@item disable-ticketing 999Allow client connects without authentication. 1000 1001@item disable-copy-paste 1002Disable copy paste between the client and the guest. 1003 1004@item disable-agent-file-xfer 1005Disable spice-vdagent based file-xfer between the client and the guest. 1006 1007@item tls-port=<nr> 1008Set the TCP port spice is listening on for encrypted channels. 1009 1010@item x509-dir=<dir> 1011Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir 1012 1013@item x509-key-file=<file> 1014@item x509-key-password=<file> 1015@item x509-cert-file=<file> 1016@item x509-cacert-file=<file> 1017@item x509-dh-key-file=<file> 1018The x509 file names can also be configured individually. 1019 1020@item tls-ciphers=<list> 1021Specify which ciphers to use. 1022 1023@item tls-channel=[main|display|cursor|inputs|record|playback] 1024@item plaintext-channel=[main|display|cursor|inputs|record|playback] 1025Force specific channel to be used with or without TLS encryption. The 1026options can be specified multiple times to configure multiple 1027channels. The special name "default" can be used to set the default 1028mode. For channels which are not explicitly forced into one mode the 1029spice client is allowed to pick tls/plaintext as he pleases. 1030 1031@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off] 1032Configure image compression (lossless). 1033Default is auto_glz. 1034 1035@item jpeg-wan-compression=[auto|never|always] 1036@item zlib-glz-wan-compression=[auto|never|always] 1037Configure wan image compression (lossy for slow links). 1038Default is auto. 1039 1040@item streaming-video=[off|all|filter] 1041Configure video stream detection. Default is filter. 1042 1043@item agent-mouse=[on|off] 1044Enable/disable passing mouse events via vdagent. Default is on. 1045 1046@item playback-compression=[on|off] 1047Enable/disable audio stream compression (using celt 0.5.1). Default is on. 1048 1049@item seamless-migration=[on|off] 1050Enable/disable spice seamless migration. Default is off. 1051 1052@end table 1053ETEXI 1054 1055DEF("portrait", 0, QEMU_OPTION_portrait, 1056 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n", 1057 QEMU_ARCH_ALL) 1058STEXI 1059@item -portrait 1060@findex -portrait 1061Rotate graphical output 90 deg left (only PXA LCD). 1062ETEXI 1063 1064DEF("rotate", HAS_ARG, QEMU_OPTION_rotate, 1065 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n", 1066 QEMU_ARCH_ALL) 1067STEXI 1068@item -rotate @var{deg} 1069@findex -rotate 1070Rotate graphical output some deg left (only PXA LCD). 1071ETEXI 1072 1073DEF("vga", HAS_ARG, QEMU_OPTION_vga, 1074 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|none]\n" 1075 " select video card type\n", QEMU_ARCH_ALL) 1076STEXI 1077@item -vga @var{type} 1078@findex -vga 1079Select type of VGA card to emulate. Valid values for @var{type} are 1080@table @option 1081@item cirrus 1082Cirrus Logic GD5446 Video card. All Windows versions starting from 1083Windows 95 should recognize and use this graphic card. For optimal 1084performances, use 16 bit color depth in the guest and the host OS. 1085(This one is the default) 1086@item std 1087Standard VGA card with Bochs VBE extensions. If your guest OS 1088supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want 1089to use high resolution modes (>= 1280x1024x16) then you should use 1090this option. 1091@item vmware 1092VMWare SVGA-II compatible adapter. Use it if you have sufficiently 1093recent XFree86/XOrg server or Windows guest with a driver for this 1094card. 1095@item qxl 1096QXL paravirtual graphic card. It is VGA compatible (including VESA 10972.0 VBE support). Works best with qxl guest drivers installed though. 1098Recommended choice when using the spice protocol. 1099@item tcx 1100(sun4m only) Sun TCX framebuffer. This is the default framebuffer for 1101sun4m machines and offers both 8-bit and 24-bit colour depths at a 1102fixed resolution of 1024x768. 1103@item cg3 1104(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer 1105for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP) 1106resolutions aimed at people wishing to run older Solaris versions. 1107@item none 1108Disable VGA card. 1109@end table 1110ETEXI 1111 1112DEF("full-screen", 0, QEMU_OPTION_full_screen, 1113 "-full-screen start in full screen\n", QEMU_ARCH_ALL) 1114STEXI 1115@item -full-screen 1116@findex -full-screen 1117Start in full screen. 1118ETEXI 1119 1120DEF("g", 1, QEMU_OPTION_g , 1121 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n", 1122 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 1123STEXI 1124@item -g @var{width}x@var{height}[x@var{depth}] 1125@findex -g 1126Set the initial graphical resolution and depth (PPC, SPARC only). 1127ETEXI 1128 1129DEF("vnc", HAS_ARG, QEMU_OPTION_vnc , 1130 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL) 1131STEXI 1132@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]] 1133@findex -vnc 1134Normally, QEMU uses SDL to display the VGA output. With this option, 1135you can have QEMU listen on VNC display @var{display} and redirect the VGA 1136display over the VNC session. It is very useful to enable the usb 1137tablet device when using this option (option @option{-usbdevice 1138tablet}). When using the VNC display, you must use the @option{-k} 1139parameter to set the keyboard layout if you are not using en-us. Valid 1140syntax for the @var{display} is 1141 1142@table @option 1143 1144@item @var{host}:@var{d} 1145 1146TCP connections will only be allowed from @var{host} on display @var{d}. 1147By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can 1148be omitted in which case the server will accept connections from any host. 1149 1150@item unix:@var{path} 1151 1152Connections will be allowed over UNIX domain sockets where @var{path} is the 1153location of a unix socket to listen for connections on. 1154 1155@item none 1156 1157VNC is initialized but not started. The monitor @code{change} command 1158can be used to later start the VNC server. 1159 1160@end table 1161 1162Following the @var{display} value there may be one or more @var{option} flags 1163separated by commas. Valid options are 1164 1165@table @option 1166 1167@item reverse 1168 1169Connect to a listening VNC client via a ``reverse'' connection. The 1170client is specified by the @var{display}. For reverse network 1171connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument 1172is a TCP port number, not a display number. 1173 1174@item websocket 1175 1176Opens an additional TCP listening port dedicated to VNC Websocket connections. 1177By definition the Websocket port is 5700+@var{display}. If @var{host} is 1178specified connections will only be allowed from this host. 1179As an alternative the Websocket port could be specified by using 1180@code{websocket}=@var{port}. 1181TLS encryption for the Websocket connection is supported if the required 1182certificates are specified with the VNC option @option{x509}. 1183 1184@item password 1185 1186Require that password based authentication is used for client connections. 1187 1188The password must be set separately using the @code{set_password} command in 1189the @ref{pcsys_monitor}. The syntax to change your password is: 1190@code{set_password <protocol> <password>} where <protocol> could be either 1191"vnc" or "spice". 1192 1193If you would like to change <protocol> password expiration, you should use 1194@code{expire_password <protocol> <expiration-time>} where expiration time could 1195be one of the following options: now, never, +seconds or UNIX time of 1196expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800 1197to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this 1198date and time). 1199 1200You can also use keywords "now" or "never" for the expiration time to 1201allow <protocol> password to expire immediately or never expire. 1202 1203@item tls 1204 1205Require that client use TLS when communicating with the VNC server. This 1206uses anonymous TLS credentials so is susceptible to a man-in-the-middle 1207attack. It is recommended that this option be combined with either the 1208@option{x509} or @option{x509verify} options. 1209 1210@item x509=@var{/path/to/certificate/dir} 1211 1212Valid if @option{tls} is specified. Require that x509 credentials are used 1213for negotiating the TLS session. The server will send its x509 certificate 1214to the client. It is recommended that a password be set on the VNC server 1215to provide authentication of the client when this is used. The path following 1216this option specifies where the x509 certificates are to be loaded from. 1217See the @ref{vnc_security} section for details on generating certificates. 1218 1219@item x509verify=@var{/path/to/certificate/dir} 1220 1221Valid if @option{tls} is specified. Require that x509 credentials are used 1222for negotiating the TLS session. The server will send its x509 certificate 1223to the client, and request that the client send its own x509 certificate. 1224The server will validate the client's certificate against the CA certificate, 1225and reject clients when validation fails. If the certificate authority is 1226trusted, this is a sufficient authentication mechanism. You may still wish 1227to set a password on the VNC server as a second authentication layer. The 1228path following this option specifies where the x509 certificates are to 1229be loaded from. See the @ref{vnc_security} section for details on generating 1230certificates. 1231 1232@item sasl 1233 1234Require that the client use SASL to authenticate with the VNC server. 1235The exact choice of authentication method used is controlled from the 1236system / user's SASL configuration file for the 'qemu' service. This 1237is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1238unprivileged user, an environment variable SASL_CONF_PATH can be used 1239to make it search alternate locations for the service config. 1240While some SASL auth methods can also provide data encryption (eg GSSAPI), 1241it is recommended that SASL always be combined with the 'tls' and 1242'x509' settings to enable use of SSL and server certificates. This 1243ensures a data encryption preventing compromise of authentication 1244credentials. See the @ref{vnc_security} section for details on using 1245SASL authentication. 1246 1247@item acl 1248 1249Turn on access control lists for checking of the x509 client certificate 1250and SASL party. For x509 certs, the ACL check is made against the 1251certificate's distinguished name. This is something that looks like 1252@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is 1253made against the username, which depending on the SASL plugin, may 1254include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}. 1255When the @option{acl} flag is set, the initial access list will be 1256empty, with a @code{deny} policy. Thus no one will be allowed to 1257use the VNC server until the ACLs have been loaded. This can be 1258achieved using the @code{acl} monitor command. 1259 1260@item lossy 1261 1262Enable lossy compression methods (gradient, JPEG, ...). If this 1263option is set, VNC client may receive lossy framebuffer updates 1264depending on its encoding settings. Enabling this option can save 1265a lot of bandwidth at the expense of quality. 1266 1267@item non-adaptive 1268 1269Disable adaptive encodings. Adaptive encodings are enabled by default. 1270An adaptive encoding will try to detect frequently updated screen regions, 1271and send updates in these regions using a lossy encoding (like JPEG). 1272This can be really helpful to save bandwidth when playing videos. Disabling 1273adaptive encodings restores the original static behavior of encodings 1274like Tight. 1275 1276@item share=[allow-exclusive|force-shared|ignore] 1277 1278Set display sharing policy. 'allow-exclusive' allows clients to ask 1279for exclusive access. As suggested by the rfb spec this is 1280implemented by dropping other connections. Connecting multiple 1281clients in parallel requires all clients asking for a shared session 1282(vncviewer: -shared switch). This is the default. 'force-shared' 1283disables exclusive client access. Useful for shared desktop sessions, 1284where you don't want someone forgetting specify -shared disconnect 1285everybody else. 'ignore' completely ignores the shared flag and 1286allows everybody connect unconditionally. Doesn't conform to the rfb 1287spec but is traditional QEMU behavior. 1288 1289@end table 1290ETEXI 1291 1292STEXI 1293@end table 1294ETEXI 1295ARCHHEADING(, QEMU_ARCH_I386) 1296 1297ARCHHEADING(i386 target only:, QEMU_ARCH_I386) 1298STEXI 1299@table @option 1300ETEXI 1301 1302DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack, 1303 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n", 1304 QEMU_ARCH_I386) 1305STEXI 1306@item -win2k-hack 1307@findex -win2k-hack 1308Use it when installing Windows 2000 to avoid a disk full bug. After 1309Windows 2000 is installed, you no longer need this option (this option 1310slows down the IDE transfers). 1311ETEXI 1312 1313HXCOMM Deprecated by -rtc 1314DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386) 1315 1316DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk, 1317 "-no-fd-bootchk disable boot signature checking for floppy disks\n", 1318 QEMU_ARCH_I386) 1319STEXI 1320@item -no-fd-bootchk 1321@findex -no-fd-bootchk 1322Disable boot signature checking for floppy disks in BIOS. May 1323be needed to boot from old floppy disks. 1324ETEXI 1325 1326DEF("no-acpi", 0, QEMU_OPTION_no_acpi, 1327 "-no-acpi disable ACPI\n", QEMU_ARCH_I386) 1328STEXI 1329@item -no-acpi 1330@findex -no-acpi 1331Disable ACPI (Advanced Configuration and Power Interface) support. Use 1332it if your guest OS complains about ACPI problems (PC target machine 1333only). 1334ETEXI 1335 1336DEF("no-hpet", 0, QEMU_OPTION_no_hpet, 1337 "-no-hpet disable HPET\n", QEMU_ARCH_I386) 1338STEXI 1339@item -no-hpet 1340@findex -no-hpet 1341Disable HPET support. 1342ETEXI 1343 1344DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable, 1345 "-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" 1346 " ACPI table description\n", QEMU_ARCH_I386) 1347STEXI 1348@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}]...] 1349@findex -acpitable 1350Add ACPI table with specified header fields and context from specified files. 1351For file=, take whole ACPI table from the specified files, including all 1352ACPI headers (possible overridden by other options). 1353For data=, only data 1354portion of the table is used, all header information is specified in the 1355command line. 1356ETEXI 1357 1358DEF("smbios", HAS_ARG, QEMU_OPTION_smbios, 1359 "-smbios file=binary\n" 1360 " load SMBIOS entry from binary file\n" 1361 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d][,uefi=on|off]\n" 1362 " specify SMBIOS type 0 fields\n" 1363 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1364 " [,uuid=uuid][,sku=str][,family=str]\n" 1365 " specify SMBIOS type 1 fields\n", QEMU_ARCH_I386) 1366STEXI 1367@item -smbios file=@var{binary} 1368@findex -smbios 1369Load SMBIOS entry from binary file. 1370 1371@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off] 1372Specify SMBIOS type 0 fields 1373 1374@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}] 1375Specify SMBIOS type 1 fields 1376ETEXI 1377 1378STEXI 1379@end table 1380ETEXI 1381DEFHEADING() 1382 1383DEFHEADING(Network options:) 1384STEXI 1385@table @option 1386ETEXI 1387 1388HXCOMM Legacy slirp options (now moved to -net user): 1389#ifdef CONFIG_SLIRP 1390DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL) 1391DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL) 1392DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL) 1393#ifndef _WIN32 1394DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL) 1395#endif 1396#endif 1397 1398DEF("net", HAS_ARG, QEMU_OPTION_net, 1399 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n" 1400 " create a new Network Interface Card and connect it to VLAN 'n'\n" 1401#ifdef CONFIG_SLIRP 1402 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=on|off]\n" 1403 " [,hostname=host][,dhcpstart=addr][,dns=addr][,dnssearch=domain][,tftp=dir]\n" 1404 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]" 1405#ifndef _WIN32 1406 "[,smb=dir[,smbserver=addr]]\n" 1407#endif 1408 " connect the user mode network stack to VLAN 'n', configure its\n" 1409 " DHCP server and enabled optional services\n" 1410#endif 1411#ifdef _WIN32 1412 "-net tap[,vlan=n][,name=str],ifname=name\n" 1413 " connect the host TAP network interface to VLAN 'n'\n" 1414#else 1415 "-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" 1416 " connect the host TAP network interface to VLAN 'n'\n" 1417 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n" 1418 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n" 1419 " to deconfigure it\n" 1420 " use '[down]script=no' to disable script execution\n" 1421 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n" 1422 " configure it\n" 1423 " use 'fd=h' to connect to an already opened TAP interface\n" 1424 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n" 1425 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n" 1426 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n" 1427 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n" 1428 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" 1429 " use vhost=on to enable experimental in kernel accelerator\n" 1430 " (only has effect for virtio guests which use MSIX)\n" 1431 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n" 1432 " use 'vhostfd=h' to connect to an already opened vhost net device\n" 1433 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n" 1434 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n" 1435 "-net bridge[,vlan=n][,name=str][,br=bridge][,helper=helper]\n" 1436 " connects a host TAP network interface to a host bridge device 'br'\n" 1437 " (default=" DEFAULT_BRIDGE_INTERFACE ") using the program 'helper'\n" 1438 " (default=" DEFAULT_BRIDGE_HELPER ")\n" 1439#endif 1440#ifdef __linux__ 1441 "-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" 1442 " connect the VLAN to an Ethernet over L2TPv3 pseudowire\n" 1443 " Linux kernel 3.3+ as well as most routers can talk\n" 1444 " L2TPv3. This transport allows connecting a VM to a VM,\n" 1445 " VM to a router and even VM to Host. It is a nearly-universal\n" 1446 " standard (RFC3391). Note - this implementation uses static\n" 1447 " pre-configured tunnels (same as the Linux kernel).\n" 1448 " use 'src=' to specify source address\n" 1449 " use 'dst=' to specify destination address\n" 1450 " use 'udp=on' to specify udp encapsulation\n" 1451 " use 'srcport=' to specify source udp port\n" 1452 " use 'dstport=' to specify destination udp port\n" 1453 " use 'ipv6=on' to force v6\n" 1454 " L2TPv3 uses cookies to prevent misconfiguration as\n" 1455 " well as a weak security measure\n" 1456 " use 'rxcookie=0x012345678' to specify a rxcookie\n" 1457 " use 'txcookie=0x012345678' to specify a txcookie\n" 1458 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n" 1459 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n" 1460 " use 'pincounter=on' to work around broken counter handling in peer\n" 1461 " use 'offset=X' to add an extra offset between header and data\n" 1462#endif 1463 "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n" 1464 " connect the vlan 'n' to another VLAN using a socket connection\n" 1465 "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port[,localaddr=addr]]\n" 1466 " connect the vlan 'n' to multicast maddr and port\n" 1467 " use 'localaddr=addr' to specify the host address to send packets from\n" 1468 "-net socket[,vlan=n][,name=str][,fd=h][,udp=host:port][,localaddr=host:port]\n" 1469 " connect the vlan 'n' to another VLAN using an UDP tunnel\n" 1470#ifdef CONFIG_VDE 1471 "-net vde[,vlan=n][,name=str][,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n" 1472 " connect the vlan 'n' to port 'n' of a vde switch running\n" 1473 " on host and listening for incoming connections on 'socketpath'.\n" 1474 " Use group 'groupname' and mode 'octalmode' to change default\n" 1475 " ownership and permissions for communication port.\n" 1476#endif 1477#ifdef CONFIG_NETMAP 1478 "-net netmap,ifname=name[,devname=nmname]\n" 1479 " attach to the existing netmap-enabled network interface 'name', or to a\n" 1480 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n" 1481 " netmap device, defaults to '/dev/netmap')\n" 1482#endif 1483 "-net dump[,vlan=n][,file=f][,len=n]\n" 1484 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n" 1485 "-net none use it alone to have zero network devices. If no -net option\n" 1486 " is provided, the default is '-net nic -net user'\n", QEMU_ARCH_ALL) 1487DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, 1488 "-netdev [" 1489#ifdef CONFIG_SLIRP 1490 "user|" 1491#endif 1492 "tap|" 1493 "bridge|" 1494#ifdef CONFIG_VDE 1495 "vde|" 1496#endif 1497#ifdef CONFIG_NETMAP 1498 "netmap|" 1499#endif 1500 "vhost-user|" 1501 "socket|" 1502 "hubport],id=str[,option][,option][,...]\n", QEMU_ARCH_ALL) 1503STEXI 1504@item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}] 1505@findex -net 1506Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n} 1507= 0 is the default). The NIC is an e1000 by default on the PC 1508target. Optionally, the MAC address can be changed to @var{mac}, the 1509device address set to @var{addr} (PCI cards only), 1510and a @var{name} can be assigned for use in monitor commands. 1511Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors 1512that the card should have; this option currently only affects virtio cards; set 1513@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single 1514NIC is created. QEMU can emulate several different models of network card. 1515Valid values for @var{type} are 1516@code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er}, 1517@code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139}, 1518@code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}. 1519Not all devices are supported on all targets. Use @code{-net nic,model=help} 1520for a list of available devices for your target. 1521 1522@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...] 1523@findex -netdev 1524@item -net user[,@var{option}][,@var{option}][,...] 1525Use the user mode network stack which requires no administrator 1526privilege to run. Valid options are: 1527 1528@table @option 1529@item vlan=@var{n} 1530Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default). 1531 1532@item id=@var{id} 1533@item name=@var{name} 1534Assign symbolic name for use in monitor commands. 1535 1536@item net=@var{addr}[/@var{mask}] 1537Set IP network address the guest will see. Optionally specify the netmask, 1538either in the form a.b.c.d or as number of valid top-most bits. Default is 153910.0.2.0/24. 1540 1541@item host=@var{addr} 1542Specify the guest-visible address of the host. Default is the 2nd IP in the 1543guest network, i.e. x.x.x.2. 1544 1545@item restrict=on|off 1546If this option is enabled, the guest will be isolated, i.e. it will not be 1547able to contact the host and no guest IP packets will be routed over the host 1548to the outside. This option does not affect any explicitly set forwarding rules. 1549 1550@item hostname=@var{name} 1551Specifies the client hostname reported by the built-in DHCP server. 1552 1553@item dhcpstart=@var{addr} 1554Specify the first of the 16 IPs the built-in DHCP server can assign. Default 1555is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31. 1556 1557@item dns=@var{addr} 1558Specify the guest-visible address of the virtual nameserver. The address must 1559be different from the host address. Default is the 3rd IP in the guest network, 1560i.e. x.x.x.3. 1561 1562@item dnssearch=@var{domain} 1563Provides an entry for the domain-search list sent by the built-in 1564DHCP server. More than one domain suffix can be transmitted by specifying 1565this option multiple times. If supported, this will cause the guest to 1566automatically try to append the given domain suffix(es) in case a domain name 1567can not be resolved. 1568 1569Example: 1570@example 1571qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...] 1572@end example 1573 1574@item tftp=@var{dir} 1575When using the user mode network stack, activate a built-in TFTP 1576server. The files in @var{dir} will be exposed as the root of a TFTP server. 1577The TFTP client on the guest must be configured in binary mode (use the command 1578@code{bin} of the Unix TFTP client). 1579 1580@item bootfile=@var{file} 1581When using the user mode network stack, broadcast @var{file} as the BOOTP 1582filename. In conjunction with @option{tftp}, this can be used to network boot 1583a guest from a local directory. 1584 1585Example (using pxelinux): 1586@example 1587qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0 1588@end example 1589 1590@item smb=@var{dir}[,smbserver=@var{addr}] 1591When using the user mode network stack, activate a built-in SMB 1592server so that Windows OSes can access to the host files in @file{@var{dir}} 1593transparently. The IP address of the SMB server can be set to @var{addr}. By 1594default the 4th IP in the guest network is used, i.e. x.x.x.4. 1595 1596In the guest Windows OS, the line: 1597@example 159810.0.2.4 smbserver 1599@end example 1600must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me) 1601or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000). 1602 1603Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}. 1604 1605Note that a SAMBA server must be installed on the host OS. 1606QEMU was tested successfully with smbd versions from Red Hat 9, 1607Fedora Core 3 and OpenSUSE 11.x. 1608 1609@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport} 1610Redirect incoming TCP or UDP connections to the host port @var{hostport} to 1611the guest IP address @var{guestaddr} on guest port @var{guestport}. If 1612@var{guestaddr} is not specified, its value is x.x.x.15 (default first address 1613given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can 1614be bound to a specific host interface. If no connection type is set, TCP is 1615used. This option can be given multiple times. 1616 1617For example, to redirect host X11 connection from screen 1 to guest 1618screen 0, use the following: 1619 1620@example 1621# on the host 1622qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...] 1623# this host xterm should open in the guest X11 server 1624xterm -display :1 1625@end example 1626 1627To redirect telnet connections from host port 5555 to telnet port on 1628the guest, use the following: 1629 1630@example 1631# on the host 1632qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...] 1633telnet localhost 5555 1634@end example 1635 1636Then when you use on the host @code{telnet localhost 5555}, you 1637connect to the guest telnet server. 1638 1639@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev} 1640@item guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command} 1641Forward guest TCP connections to the IP address @var{server} on port @var{port} 1642to the character device @var{dev} or to a program executed by @var{cmd:command} 1643which gets spawned for each connection. This option can be given multiple times. 1644 1645You can either use a chardev directly and have that one used throughout QEMU's 1646lifetime, like in the following example: 1647 1648@example 1649# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever 1650# the guest accesses it 1651qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...] 1652@end example 1653 1654Or you can execute a command on every TCP connection established by the guest, 1655so that QEMU behaves similar to an inetd process for that virtual server: 1656 1657@example 1658# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 1659# and connect the TCP stream to its stdin/stdout 1660qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321' 1661@end example 1662 1663@end table 1664 1665Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still 1666processed and applied to -net user. Mixing them with the new configuration 1667syntax gives undefined results. Their use for new applications is discouraged 1668as they will be removed from future versions. 1669 1670@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}] 1671@item -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}] 1672Connect the host TAP network interface @var{name} to VLAN @var{n}. 1673 1674Use the network script @var{file} to configure it and the network script 1675@var{dfile} to deconfigure it. If @var{name} is not provided, the OS 1676automatically provides one. The default network configure script is 1677@file{/etc/qemu-ifup} and the default network deconfigure script is 1678@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no} 1679to disable script execution. 1680 1681If running QEMU as an unprivileged user, use the network helper 1682@var{helper} to configure the TAP interface. The default network 1683helper executable is @file{/path/to/qemu-bridge-helper}. 1684 1685@option{fd}=@var{h} can be used to specify the handle of an already 1686opened host TAP interface. 1687 1688Examples: 1689 1690@example 1691#launch a QEMU instance with the default network script 1692qemu-system-i386 linux.img -net nic -net tap 1693@end example 1694 1695@example 1696#launch a QEMU instance with two NICs, each one connected 1697#to a TAP device 1698qemu-system-i386 linux.img \ 1699 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \ 1700 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1 1701@end example 1702 1703@example 1704#launch a QEMU instance with the default network helper to 1705#connect a TAP device to bridge br0 1706qemu-system-i386 linux.img \ 1707 -net nic -net tap,"helper=/path/to/qemu-bridge-helper" 1708@end example 1709 1710@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}] 1711@item -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}] 1712Connect a host TAP network interface to a host bridge device. 1713 1714Use the network helper @var{helper} to configure the TAP interface and 1715attach it to the bridge. The default network helper executable is 1716@file{/path/to/qemu-bridge-helper} and the default bridge 1717device is @file{br0}. 1718 1719Examples: 1720 1721@example 1722#launch a QEMU instance with the default network helper to 1723#connect a TAP device to bridge br0 1724qemu-system-i386 linux.img -net bridge -net nic,model=virtio 1725@end example 1726 1727@example 1728#launch a QEMU instance with the default network helper to 1729#connect a TAP device to bridge qemubr0 1730qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio 1731@end example 1732 1733@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 1734@item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 1735 1736Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual 1737machine using a TCP socket connection. If @option{listen} is 1738specified, QEMU waits for incoming connections on @var{port} 1739(@var{host} is optional). @option{connect} is used to connect to 1740another QEMU instance using the @option{listen} option. @option{fd}=@var{h} 1741specifies an already opened TCP socket. 1742 1743Example: 1744@example 1745# launch a first QEMU instance 1746qemu-system-i386 linux.img \ 1747 -net nic,macaddr=52:54:00:12:34:56 \ 1748 -net socket,listen=:1234 1749# connect the VLAN 0 of this instance to the VLAN 0 1750# of the first instance 1751qemu-system-i386 linux.img \ 1752 -net nic,macaddr=52:54:00:12:34:57 \ 1753 -net socket,connect=127.0.0.1:1234 1754@end example 1755 1756@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 1757@item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 1758 1759Create a VLAN @var{n} shared with another QEMU virtual 1760machines using a UDP multicast socket, effectively making a bus for 1761every QEMU with same multicast address @var{maddr} and @var{port}. 1762NOTES: 1763@enumerate 1764@item 1765Several QEMU can be running on different hosts and share same bus (assuming 1766correct multicast setup for these hosts). 1767@item 1768mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see 1769@url{http://user-mode-linux.sf.net}. 1770@item 1771Use @option{fd=h} to specify an already opened UDP multicast socket. 1772@end enumerate 1773 1774Example: 1775@example 1776# launch one QEMU instance 1777qemu-system-i386 linux.img \ 1778 -net nic,macaddr=52:54:00:12:34:56 \ 1779 -net socket,mcast=230.0.0.1:1234 1780# launch another QEMU instance on same "bus" 1781qemu-system-i386 linux.img \ 1782 -net nic,macaddr=52:54:00:12:34:57 \ 1783 -net socket,mcast=230.0.0.1:1234 1784# launch yet another QEMU instance on same "bus" 1785qemu-system-i386 linux.img \ 1786 -net nic,macaddr=52:54:00:12:34:58 \ 1787 -net socket,mcast=230.0.0.1:1234 1788@end example 1789 1790Example (User Mode Linux compat.): 1791@example 1792# launch QEMU instance (note mcast address selected 1793# is UML's default) 1794qemu-system-i386 linux.img \ 1795 -net nic,macaddr=52:54:00:12:34:56 \ 1796 -net socket,mcast=239.192.168.1:1102 1797# launch UML 1798/path/to/linux ubd0=/path/to/root_fs eth0=mcast 1799@end example 1800 1801Example (send packets from host's 1.2.3.4): 1802@example 1803qemu-system-i386 linux.img \ 1804 -net nic,macaddr=52:54:00:12:34:56 \ 1805 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4 1806@end example 1807 1808@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}] 1809@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}] 1810Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular 1811protocol to transport Ethernet (and other Layer 2) data frames between 1812two systems. It is present in routers, firewalls and the Linux kernel 1813(from version 3.3 onwards). 1814 1815This transport allows a VM to communicate to another VM, router or firewall directly. 1816 1817@item src=@var{srcaddr} 1818 source address (mandatory) 1819@item dst=@var{dstaddr} 1820 destination address (mandatory) 1821@item udp 1822 select udp encapsulation (default is ip). 1823@item srcport=@var{srcport} 1824 source udp port. 1825@item dstport=@var{dstport} 1826 destination udp port. 1827@item ipv6 1828 force v6, otherwise defaults to v4. 1829@item rxcookie=@var{rxcookie} 1830@item txcookie=@var{txcookie} 1831 Cookies are a weak form of security in the l2tpv3 specification. 1832Their function is mostly to prevent misconfiguration. By default they are 32 1833bit. 1834@item cookie64 1835 Set cookie size to 64 bit instead of the default 32 1836@item counter=off 1837 Force a 'cut-down' L2TPv3 with no counter as in 1838draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00 1839@item pincounter=on 1840 Work around broken counter handling in peer. This may also help on 1841networks which have packet reorder. 1842@item offset=@var{offset} 1843 Add an extra offset between header and data 1844 1845For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan 1846on the remote Linux host 1.2.3.4: 1847@example 1848# Setup tunnel on linux host using raw ip as encapsulation 1849# on 1.2.3.4 1850ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \ 1851 encap udp udp_sport 16384 udp_dport 16384 1852ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \ 1853 0xFFFFFFFF peer_session_id 0xFFFFFFFF 1854ifconfig vmtunnel0 mtu 1500 1855ifconfig vmtunnel0 up 1856brctl addif br-lan vmtunnel0 1857 1858 1859# on 4.3.2.1 1860# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter 1861 1862qemu-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 1863 1864 1865@end example 1866 1867@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 1868@item -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 1869Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and 1870listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname} 1871and MODE @var{octalmode} to change default ownership and permissions for 1872communication port. This option is only available if QEMU has been compiled 1873with vde support enabled. 1874 1875Example: 1876@example 1877# launch vde switch 1878vde_switch -F -sock /tmp/myswitch 1879# launch QEMU instance 1880qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch 1881@end example 1882 1883@item -netdev hubport,id=@var{id},hubid=@var{hubid} 1884 1885Create a hub port on QEMU "vlan" @var{hubid}. 1886 1887The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single 1888netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the 1889required hub automatically. 1890 1891@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off] 1892 1893Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should 1894be a unix domain socket backed one. The vhost-user uses a specifically defined 1895protocol to pass vhost ioctl replacement messages to an application on the other 1896end of the socket. On non-MSIX guests, the feature can be forced with 1897@var{vhostforce}. 1898 1899Example: 1900@example 1901qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \ 1902 -numa node,memdev=mem \ 1903 -chardev socket,path=/path/to/socket \ 1904 -netdev type=vhost-user,id=net0,chardev=chr0 \ 1905 -device virtio-net-pci,netdev=net0 1906@end example 1907 1908@item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}] 1909Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default). 1910At most @var{len} bytes (64k by default) per packet are stored. The file format is 1911libpcap, so it can be analyzed with tools such as tcpdump or Wireshark. 1912 1913@item -net none 1914Indicate that no network devices should be configured. It is used to 1915override the default configuration (@option{-net nic -net user}) which 1916is activated if no @option{-net} options are provided. 1917ETEXI 1918 1919STEXI 1920@end table 1921ETEXI 1922DEFHEADING() 1923 1924DEFHEADING(Character device options:) 1925STEXI 1926 1927The general form of a character device option is: 1928@table @option 1929ETEXI 1930 1931DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, 1932 "-chardev null,id=id[,mux=on|off]\n" 1933 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay]\n" 1934 " [,server][,nowait][,telnet][,mux=on|off] (tcp)\n" 1935 "-chardev socket,id=id,path=path[,server][,nowait][,telnet],[mux=on|off] (unix)\n" 1936 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" 1937 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n" 1938 "-chardev msmouse,id=id[,mux=on|off]\n" 1939 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n" 1940 " [,mux=on|off]\n" 1941 "-chardev ringbuf,id=id[,size=size]\n" 1942 "-chardev file,id=id,path=path[,mux=on|off]\n" 1943 "-chardev pipe,id=id,path=path[,mux=on|off]\n" 1944#ifdef _WIN32 1945 "-chardev console,id=id[,mux=on|off]\n" 1946 "-chardev serial,id=id,path=path[,mux=on|off]\n" 1947#else 1948 "-chardev pty,id=id[,mux=on|off]\n" 1949 "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n" 1950#endif 1951#ifdef CONFIG_BRLAPI 1952 "-chardev braille,id=id[,mux=on|off]\n" 1953#endif 1954#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 1955 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) 1956 "-chardev serial,id=id,path=path[,mux=on|off]\n" 1957 "-chardev tty,id=id,path=path[,mux=on|off]\n" 1958#endif 1959#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) 1960 "-chardev parallel,id=id,path=path[,mux=on|off]\n" 1961 "-chardev parport,id=id,path=path[,mux=on|off]\n" 1962#endif 1963#if defined(CONFIG_SPICE) 1964 "-chardev spicevmc,id=id,name=name[,debug=debug]\n" 1965 "-chardev spiceport,id=id,name=name[,debug=debug]\n" 1966#endif 1967 , QEMU_ARCH_ALL 1968) 1969 1970STEXI 1971@item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}] 1972@findex -chardev 1973Backend is one of: 1974@option{null}, 1975@option{socket}, 1976@option{udp}, 1977@option{msmouse}, 1978@option{vc}, 1979@option{ringbuf}, 1980@option{file}, 1981@option{pipe}, 1982@option{console}, 1983@option{serial}, 1984@option{pty}, 1985@option{stdio}, 1986@option{braille}, 1987@option{tty}, 1988@option{parallel}, 1989@option{parport}, 1990@option{spicevmc}. 1991@option{spiceport}. 1992The specific backend will determine the applicable options. 1993 1994All devices must have an id, which can be any string up to 127 characters long. 1995It is used to uniquely identify this device in other command line directives. 1996 1997A character device may be used in multiplexing mode by multiple front-ends. 1998The key sequence of @key{Control-a} and @key{c} will rotate the input focus 1999between attached front-ends. Specify @option{mux=on} to enable this mode. 2000 2001Options to each backend are described below. 2002 2003@item -chardev null ,id=@var{id} 2004A void device. This device will not emit any data, and will drop any data it 2005receives. The null backend does not take any options. 2006 2007@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] 2008 2009Create a two-way stream socket, which can be either a TCP or a unix socket. A 2010unix socket will be created if @option{path} is specified. Behaviour is 2011undefined if TCP options are specified for a unix socket. 2012 2013@option{server} specifies that the socket shall be a listening socket. 2014 2015@option{nowait} specifies that QEMU should not block waiting for a client to 2016connect to a listening socket. 2017 2018@option{telnet} specifies that traffic on the socket should interpret telnet 2019escape sequences. 2020 2021TCP and unix socket options are given below: 2022 2023@table @option 2024 2025@item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay] 2026 2027@option{host} for a listening socket specifies the local address to be bound. 2028For a connecting socket species the remote host to connect to. @option{host} is 2029optional for listening sockets. If not specified it defaults to @code{0.0.0.0}. 2030 2031@option{port} for a listening socket specifies the local port to be bound. For a 2032connecting socket specifies the port on the remote host to connect to. 2033@option{port} can be given as either a port number or a service name. 2034@option{port} is required. 2035 2036@option{to} is only relevant to listening sockets. If it is specified, and 2037@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up 2038to and including @option{to} until it succeeds. @option{to} must be specified 2039as a port number. 2040 2041@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2042If neither is specified the socket may use either protocol. 2043 2044@option{nodelay} disables the Nagle algorithm. 2045 2046@item unix options: path=@var{path} 2047 2048@option{path} specifies the local path of the unix socket. @option{path} is 2049required. 2050 2051@end table 2052 2053@item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6] 2054 2055Sends all traffic from the guest to a remote host over UDP. 2056 2057@option{host} specifies the remote host to connect to. If not specified it 2058defaults to @code{localhost}. 2059 2060@option{port} specifies the port on the remote host to connect to. @option{port} 2061is required. 2062 2063@option{localaddr} specifies the local address to bind to. If not specified it 2064defaults to @code{0.0.0.0}. 2065 2066@option{localport} specifies the local port to bind to. If not specified any 2067available local port will be used. 2068 2069@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2070If neither is specified the device may use either protocol. 2071 2072@item -chardev msmouse ,id=@var{id} 2073 2074Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not 2075take any options. 2076 2077@item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]] 2078 2079Connect to a QEMU text console. @option{vc} may optionally be given a specific 2080size. 2081 2082@option{width} and @option{height} specify the width and height respectively of 2083the console, in pixels. 2084 2085@option{cols} and @option{rows} specify that the console be sized to fit a text 2086console with the given dimensions. 2087 2088@item -chardev ringbuf ,id=@var{id} [,size=@var{size}] 2089 2090Create a ring buffer with fixed size @option{size}. 2091@var{size} must be a power of two, and defaults to @code{64K}). 2092 2093@item -chardev file ,id=@var{id} ,path=@var{path} 2094 2095Log all traffic received from the guest to a file. 2096 2097@option{path} specifies the path of the file to be opened. This file will be 2098created if it does not already exist, and overwritten if it does. @option{path} 2099is required. 2100 2101@item -chardev pipe ,id=@var{id} ,path=@var{path} 2102 2103Create a two-way connection to the guest. The behaviour differs slightly between 2104Windows hosts and other hosts: 2105 2106On Windows, a single duplex pipe will be created at 2107@file{\\.pipe\@option{path}}. 2108 2109On other hosts, 2 pipes will be created called @file{@option{path}.in} and 2110@file{@option{path}.out}. Data written to @file{@option{path}.in} will be 2111received by the guest. Data written by the guest can be read from 2112@file{@option{path}.out}. QEMU will not create these fifos, and requires them to 2113be present. 2114 2115@option{path} forms part of the pipe path as described above. @option{path} is 2116required. 2117 2118@item -chardev console ,id=@var{id} 2119 2120Send traffic from the guest to QEMU's standard output. @option{console} does not 2121take any options. 2122 2123@option{console} is only available on Windows hosts. 2124 2125@item -chardev serial ,id=@var{id} ,path=@option{path} 2126 2127Send traffic from the guest to a serial device on the host. 2128 2129On Unix hosts serial will actually accept any tty device, 2130not only serial lines. 2131 2132@option{path} specifies the name of the serial device to open. 2133 2134@item -chardev pty ,id=@var{id} 2135 2136Create a new pseudo-terminal on the host and connect to it. @option{pty} does 2137not take any options. 2138 2139@option{pty} is not available on Windows hosts. 2140 2141@item -chardev stdio ,id=@var{id} [,signal=on|off] 2142Connect to standard input and standard output of the QEMU process. 2143 2144@option{signal} controls if signals are enabled on the terminal, that includes 2145exiting QEMU with the key sequence @key{Control-c}. This option is enabled by 2146default, use @option{signal=off} to disable it. 2147 2148@option{stdio} is not available on Windows hosts. 2149 2150@item -chardev braille ,id=@var{id} 2151 2152Connect to a local BrlAPI server. @option{braille} does not take any options. 2153 2154@item -chardev tty ,id=@var{id} ,path=@var{path} 2155 2156@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and 2157DragonFlyBSD hosts. It is an alias for @option{serial}. 2158 2159@option{path} specifies the path to the tty. @option{path} is required. 2160 2161@item -chardev parallel ,id=@var{id} ,path=@var{path} 2162@item -chardev parport ,id=@var{id} ,path=@var{path} 2163 2164@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts. 2165 2166Connect to a local parallel port. 2167 2168@option{path} specifies the path to the parallel port device. @option{path} is 2169required. 2170 2171@item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name} 2172 2173@option{spicevmc} is only available when spice support is built in. 2174 2175@option{debug} debug level for spicevmc 2176 2177@option{name} name of spice channel to connect to 2178 2179Connect to a spice virtual machine channel, such as vdiport. 2180 2181@item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name} 2182 2183@option{spiceport} is only available when spice support is built in. 2184 2185@option{debug} debug level for spicevmc 2186 2187@option{name} name of spice port to connect to 2188 2189Connect to a spice port, allowing a Spice client to handle the traffic 2190identified by a name (preferably a fqdn). 2191ETEXI 2192 2193STEXI 2194@end table 2195ETEXI 2196DEFHEADING() 2197 2198DEFHEADING(Device URL Syntax:) 2199STEXI 2200 2201In addition to using normal file images for the emulated storage devices, 2202QEMU can also use networked resources such as iSCSI devices. These are 2203specified using a special URL syntax. 2204 2205@table @option 2206@item iSCSI 2207iSCSI support allows QEMU to access iSCSI resources directly and use as 2208images for the guest storage. Both disk and cdrom images are supported. 2209 2210Syntax for specifying iSCSI LUNs is 2211``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>'' 2212 2213By default qemu will use the iSCSI initiator-name 2214'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command 2215line or a configuration file. 2216 2217 2218Example (without authentication): 2219@example 2220qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \ 2221 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \ 2222 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 2223@end example 2224 2225Example (CHAP username/password via URL): 2226@example 2227qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1 2228@end example 2229 2230Example (CHAP username/password via environment variables): 2231@example 2232LIBISCSI_CHAP_USERNAME="user" \ 2233LIBISCSI_CHAP_PASSWORD="password" \ 2234qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 2235@end example 2236 2237iSCSI support is an optional feature of QEMU and only available when 2238compiled and linked against libiscsi. 2239ETEXI 2240DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi, 2241 "-iscsi [user=user][,password=password]\n" 2242 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n" 2243 " [,initiator-name=initiator-iqn][,id=target-iqn]\n" 2244 " iSCSI session parameters\n", QEMU_ARCH_ALL) 2245STEXI 2246 2247iSCSI parameters such as username and password can also be specified via 2248a configuration file. See qemu-doc for more information and examples. 2249 2250@item NBD 2251QEMU supports NBD (Network Block Devices) both using TCP protocol as well 2252as Unix Domain Sockets. 2253 2254Syntax for specifying a NBD device using TCP 2255``nbd:<server-ip>:<port>[:exportname=<export>]'' 2256 2257Syntax for specifying a NBD device using Unix Domain Sockets 2258``nbd:unix:<domain-socket>[:exportname=<export>]'' 2259 2260 2261Example for TCP 2262@example 2263qemu-system-i386 --drive file=nbd:192.0.2.1:30000 2264@end example 2265 2266Example for Unix Domain Sockets 2267@example 2268qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket 2269@end example 2270 2271@item SSH 2272QEMU supports SSH (Secure Shell) access to remote disks. 2273 2274Examples: 2275@example 2276qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img 2277qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img 2278@end example 2279 2280Currently authentication must be done using ssh-agent. Other 2281authentication methods may be supported in future. 2282 2283@item Sheepdog 2284Sheepdog is a distributed storage system for QEMU. 2285QEMU supports using either local sheepdog devices or remote networked 2286devices. 2287 2288Syntax for specifying a sheepdog device 2289@example 2290sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag] 2291@end example 2292 2293Example 2294@example 2295qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine 2296@end example 2297 2298See also @url{http://http://www.osrg.net/sheepdog/}. 2299 2300@item GlusterFS 2301GlusterFS is an user space distributed file system. 2302QEMU supports the use of GlusterFS volumes for hosting VM disk images using 2303TCP, Unix Domain Sockets and RDMA transport protocols. 2304 2305Syntax for specifying a VM disk image on GlusterFS volume is 2306@example 2307gluster[+transport]://[server[:port]]/volname/image[?socket=...] 2308@end example 2309 2310 2311Example 2312@example 2313qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img 2314@end example 2315 2316See also @url{http://www.gluster.org}. 2317 2318@item HTTP/HTTPS/FTP/FTPS/TFTP 2319QEMU supports read-only access to files accessed over http(s), ftp(s) and tftp. 2320 2321Syntax using a single filename: 2322@example 2323<protocol>://[<username>[:<password>]@@]<host>/<path> 2324@end example 2325 2326where: 2327@table @option 2328@item protocol 2329'http', 'https', 'ftp', 'ftps', or 'tftp'. 2330 2331@item username 2332Optional username for authentication to the remote server. 2333 2334@item password 2335Optional password for authentication to the remote server. 2336 2337@item host 2338Address of the remote server. 2339 2340@item path 2341Path on the remote server, including any query string. 2342@end table 2343 2344The following options are also supported: 2345@table @option 2346@item url 2347The full URL when passing options to the driver explicitly. 2348 2349@item readahead 2350The amount of data to read ahead with each range request to the remote server. 2351This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it 2352does not have a suffix, it will be assumed to be in bytes. The value must be a 2353multiple of 512 bytes. It defaults to 256k. 2354 2355@item sslverify 2356Whether to verify the remote server's certificate when connecting over SSL. It 2357can have the value 'on' or 'off'. It defaults to 'on'. 2358 2359@item cookie 2360Send this cookie (it can also be a list of cookies separated by ';') with 2361each outgoing request. Only supported when using protocols such as HTTP 2362which support cookies, otherwise ignored. 2363 2364@item timeout 2365Set the timeout in seconds of the CURL connection. This timeout is the time 2366that CURL waits for a response from the remote server to get the size of the 2367image to be downloaded. If not set, the default timeout of 5 seconds is used. 2368@end table 2369 2370Note that when passing options to qemu explicitly, @option{driver} is the value 2371of <protocol>. 2372 2373Example: boot from a remote Fedora 20 live ISO image 2374@example 2375qemu-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 2376 2377qemu-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 2378@end example 2379 2380Example: boot from a remote Fedora 20 cloud image using a local overlay for 2381writes, copy-on-read, and a readahead of 64k 2382@example 2383qemu-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 2384 2385qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on 2386@end example 2387 2388Example: boot from an image stored on a VMware vSphere server with a self-signed 2389certificate using a local overlay for writes, a readahead of 64k and a timeout 2390of 10 seconds. 2391@example 2392qemu-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 2393 2394qemu-system-x86_64 -drive file=/tmp/test.qcow2 2395@end example 2396ETEXI 2397 2398STEXI 2399@end table 2400ETEXI 2401 2402DEFHEADING(Bluetooth(R) options:) 2403STEXI 2404@table @option 2405ETEXI 2406 2407DEF("bt", HAS_ARG, QEMU_OPTION_bt, \ 2408 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \ 2409 "-bt hci,host[:id]\n" \ 2410 " use host's HCI with the given name\n" \ 2411 "-bt hci[,vlan=n]\n" \ 2412 " emulate a standard HCI in virtual scatternet 'n'\n" \ 2413 "-bt vhci[,vlan=n]\n" \ 2414 " add host computer to virtual scatternet 'n' using VHCI\n" \ 2415 "-bt device:dev[,vlan=n]\n" \ 2416 " emulate a bluetooth device 'dev' in scatternet 'n'\n", 2417 QEMU_ARCH_ALL) 2418STEXI 2419@item -bt hci[...] 2420@findex -bt 2421Defines the function of the corresponding Bluetooth HCI. -bt options 2422are matched with the HCIs present in the chosen machine type. For 2423example when emulating a machine with only one HCI built into it, only 2424the first @code{-bt hci[...]} option is valid and defines the HCI's 2425logic. The Transport Layer is decided by the machine type. Currently 2426the machines @code{n800} and @code{n810} have one HCI and all other 2427machines have none. 2428 2429@anchor{bt-hcis} 2430The following three types are recognized: 2431 2432@table @option 2433@item -bt hci,null 2434(default) The corresponding Bluetooth HCI assumes no internal logic 2435and will not respond to any HCI commands or emit events. 2436 2437@item -bt hci,host[:@var{id}] 2438(@code{bluez} only) The corresponding HCI passes commands / events 2439to / from the physical HCI identified by the name @var{id} (default: 2440@code{hci0}) on the computer running QEMU. Only available on @code{bluez} 2441capable systems like Linux. 2442 2443@item -bt hci[,vlan=@var{n}] 2444Add a virtual, standard HCI that will participate in the Bluetooth 2445scatternet @var{n} (default @code{0}). Similarly to @option{-net} 2446VLANs, devices inside a bluetooth network @var{n} can only communicate 2447with other devices in the same network (scatternet). 2448@end table 2449 2450@item -bt vhci[,vlan=@var{n}] 2451(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached 2452to the host bluetooth stack instead of to the emulated target. This 2453allows the host and target machines to participate in a common scatternet 2454and communicate. Requires the Linux @code{vhci} driver installed. Can 2455be used as following: 2456 2457@example 2458qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5 2459@end example 2460 2461@item -bt device:@var{dev}[,vlan=@var{n}] 2462Emulate a bluetooth device @var{dev} and place it in network @var{n} 2463(default @code{0}). QEMU can only emulate one type of bluetooth devices 2464currently: 2465 2466@table @option 2467@item keyboard 2468Virtual wireless keyboard implementing the HIDP bluetooth profile. 2469@end table 2470ETEXI 2471 2472STEXI 2473@end table 2474ETEXI 2475DEFHEADING() 2476 2477#ifdef CONFIG_TPM 2478DEFHEADING(TPM device options:) 2479 2480DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \ 2481 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n" 2482 " use path to provide path to a character device; default is /dev/tpm0\n" 2483 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n" 2484 " not provided it will be searched for in /sys/class/misc/tpm?/device\n", 2485 QEMU_ARCH_ALL) 2486STEXI 2487 2488The general form of a TPM device option is: 2489@table @option 2490 2491@item -tpmdev @var{backend} ,id=@var{id} [,@var{options}] 2492@findex -tpmdev 2493Backend type must be: 2494@option{passthrough}. 2495 2496The specific backend type will determine the applicable options. 2497The @code{-tpmdev} option creates the TPM backend and requires a 2498@code{-device} option that specifies the TPM frontend interface model. 2499 2500Options to each backend are described below. 2501 2502Use 'help' to print all available TPM backend types. 2503@example 2504qemu -tpmdev help 2505@end example 2506 2507@item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path} 2508 2509(Linux-host only) Enable access to the host's TPM using the passthrough 2510driver. 2511 2512@option{path} specifies the path to the host's TPM device, i.e., on 2513a Linux host this would be @code{/dev/tpm0}. 2514@option{path} is optional and by default @code{/dev/tpm0} is used. 2515 2516@option{cancel-path} specifies the path to the host TPM device's sysfs 2517entry allowing for cancellation of an ongoing TPM command. 2518@option{cancel-path} is optional and by default QEMU will search for the 2519sysfs entry to use. 2520 2521Some notes about using the host's TPM with the passthrough driver: 2522 2523The TPM device accessed by the passthrough driver must not be 2524used by any other application on the host. 2525 2526Since the host's firmware (BIOS/UEFI) has already initialized the TPM, 2527the VM's firmware (BIOS/UEFI) will not be able to initialize the 2528TPM again and may therefore not show a TPM-specific menu that would 2529otherwise allow the user to configure the TPM, e.g., allow the user to 2530enable/disable or activate/deactivate the TPM. 2531Further, if TPM ownership is released from within a VM then the host's TPM 2532will get disabled and deactivated. To enable and activate the 2533TPM again afterwards, the host has to be rebooted and the user is 2534required to enter the firmware's menu to enable and activate the TPM. 2535If the TPM is left disabled and/or deactivated most TPM commands will fail. 2536 2537To create a passthrough TPM use the following two options: 2538@example 2539-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0 2540@end example 2541Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by 2542@code{tpmdev=tpm0} in the device option. 2543 2544@end table 2545 2546ETEXI 2547 2548DEFHEADING() 2549 2550#endif 2551 2552DEFHEADING(Linux/Multiboot boot specific:) 2553STEXI 2554 2555When using these options, you can use a given Linux or Multiboot 2556kernel without installing it in the disk image. It can be useful 2557for easier testing of various kernels. 2558 2559@table @option 2560ETEXI 2561 2562DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \ 2563 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL) 2564STEXI 2565@item -kernel @var{bzImage} 2566@findex -kernel 2567Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel 2568or in multiboot format. 2569ETEXI 2570 2571DEF("append", HAS_ARG, QEMU_OPTION_append, \ 2572 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL) 2573STEXI 2574@item -append @var{cmdline} 2575@findex -append 2576Use @var{cmdline} as kernel command line 2577ETEXI 2578 2579DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \ 2580 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL) 2581STEXI 2582@item -initrd @var{file} 2583@findex -initrd 2584Use @var{file} as initial ram disk. 2585 2586@item -initrd "@var{file1} arg=foo,@var{file2}" 2587 2588This syntax is only available with multiboot. 2589 2590Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the 2591first module. 2592ETEXI 2593 2594DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \ 2595 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL) 2596STEXI 2597@item -dtb @var{file} 2598@findex -dtb 2599Use @var{file} as a device tree binary (dtb) image and pass it to the kernel 2600on boot. 2601ETEXI 2602 2603STEXI 2604@end table 2605ETEXI 2606DEFHEADING() 2607 2608DEFHEADING(Debug/Expert options:) 2609STEXI 2610@table @option 2611ETEXI 2612 2613DEF("serial", HAS_ARG, QEMU_OPTION_serial, \ 2614 "-serial dev redirect the serial port to char device 'dev'\n", 2615 QEMU_ARCH_ALL) 2616STEXI 2617@item -serial @var{dev} 2618@findex -serial 2619Redirect the virtual serial port to host character device 2620@var{dev}. The default device is @code{vc} in graphical mode and 2621@code{stdio} in non graphical mode. 2622 2623This option can be used several times to simulate up to 4 serial 2624ports. 2625 2626Use @code{-serial none} to disable all serial ports. 2627 2628Available character devices are: 2629@table @option 2630@item vc[:@var{W}x@var{H}] 2631Virtual console. Optionally, a width and height can be given in pixel with 2632@example 2633vc:800x600 2634@end example 2635It is also possible to specify width or height in characters: 2636@example 2637vc:80Cx24C 2638@end example 2639@item pty 2640[Linux only] Pseudo TTY (a new PTY is automatically allocated) 2641@item none 2642No device is allocated. 2643@item null 2644void device 2645@item chardev:@var{id} 2646Use a named character device defined with the @code{-chardev} option. 2647@item /dev/XXX 2648[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port 2649parameters are set according to the emulated ones. 2650@item /dev/parport@var{N} 2651[Linux only, parallel port only] Use host parallel port 2652@var{N}. Currently SPP and EPP parallel port features can be used. 2653@item file:@var{filename} 2654Write output to @var{filename}. No character can be read. 2655@item stdio 2656[Unix only] standard input/output 2657@item pipe:@var{filename} 2658name pipe @var{filename} 2659@item COM@var{n} 2660[Windows only] Use host serial port @var{n} 2661@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}] 2662This implements UDP Net Console. 2663When @var{remote_host} or @var{src_ip} are not specified 2664they default to @code{0.0.0.0}. 2665When not using a specified @var{src_port} a random port is automatically chosen. 2666 2667If you just want a simple readonly console you can use @code{netcat} or 2668@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as: 2669@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it 2670will appear in the netconsole session. 2671 2672If you plan to send characters back via netconsole or you want to stop 2673and start QEMU a lot of times, you should have QEMU use the same 2674source port each time by using something like @code{-serial 2675udp::4555@@:4556} to QEMU. Another approach is to use a patched 2676version of netcat which can listen to a TCP port and send and receive 2677characters via udp. If you have a patched version of netcat which 2678activates telnet remote echo and single char transfer, then you can 2679use the following options to step up a netcat redirector to allow 2680telnet on port 5555 to access the QEMU port. 2681@table @code 2682@item QEMU Options: 2683-serial udp::4555@@:4556 2684@item netcat options: 2685-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T 2686@item telnet options: 2687localhost 5555 2688@end table 2689 2690@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay] 2691The TCP Net Console has two modes of operation. It can send the serial 2692I/O to a location or wait for a connection from a location. By default 2693the TCP Net Console is sent to @var{host} at the @var{port}. If you use 2694the @var{server} option QEMU will wait for a client socket application 2695to connect to the port before continuing, unless the @code{nowait} 2696option was specified. The @code{nodelay} option disables the Nagle buffering 2697algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only 2698one TCP connection at a time is accepted. You can use @code{telnet} to 2699connect to the corresponding character device. 2700@table @code 2701@item Example to send tcp console to 192.168.0.2 port 4444 2702-serial tcp:192.168.0.2:4444 2703@item Example to listen and wait on port 4444 for connection 2704-serial tcp::4444,server 2705@item Example to not wait and listen on ip 192.168.0.100 port 4444 2706-serial tcp:192.168.0.100:4444,server,nowait 2707@end table 2708 2709@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay] 2710The telnet protocol is used instead of raw tcp sockets. The options 2711work the same as if you had specified @code{-serial tcp}. The 2712difference is that the port acts like a telnet server or client using 2713telnet option negotiation. This will also allow you to send the 2714MAGIC_SYSRQ sequence if you use a telnet that supports sending the break 2715sequence. Typically in unix telnet you do it with Control-] and then 2716type "send break" followed by pressing the enter key. 2717 2718@item unix:@var{path}[,server][,nowait] 2719A unix domain socket is used instead of a tcp socket. The option works the 2720same as if you had specified @code{-serial tcp} except the unix domain socket 2721@var{path} is used for connections. 2722 2723@item mon:@var{dev_string} 2724This is a special option to allow the monitor to be multiplexed onto 2725another serial port. The monitor is accessed with key sequence of 2726@key{Control-a} and then pressing @key{c}. 2727@var{dev_string} should be any one of the serial devices specified 2728above. An example to multiplex the monitor onto a telnet server 2729listening on port 4444 would be: 2730@table @code 2731@item -serial mon:telnet::4444,server,nowait 2732@end table 2733When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate 2734QEMU any more but will be passed to the guest instead. 2735 2736@item braille 2737Braille device. This will use BrlAPI to display the braille output on a real 2738or fake device. 2739 2740@item msmouse 2741Three button serial mouse. Configure the guest to use Microsoft protocol. 2742@end table 2743ETEXI 2744 2745DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \ 2746 "-parallel dev redirect the parallel port to char device 'dev'\n", 2747 QEMU_ARCH_ALL) 2748STEXI 2749@item -parallel @var{dev} 2750@findex -parallel 2751Redirect the virtual parallel port to host device @var{dev} (same 2752devices as the serial port). On Linux hosts, @file{/dev/parportN} can 2753be used to use hardware devices connected on the corresponding host 2754parallel port. 2755 2756This option can be used several times to simulate up to 3 parallel 2757ports. 2758 2759Use @code{-parallel none} to disable all parallel ports. 2760ETEXI 2761 2762DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \ 2763 "-monitor dev redirect the monitor to char device 'dev'\n", 2764 QEMU_ARCH_ALL) 2765STEXI 2766@item -monitor @var{dev} 2767@findex -monitor 2768Redirect the monitor to host device @var{dev} (same devices as the 2769serial port). 2770The default device is @code{vc} in graphical mode and @code{stdio} in 2771non graphical mode. 2772Use @code{-monitor none} to disable the default monitor. 2773ETEXI 2774DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \ 2775 "-qmp dev like -monitor but opens in 'control' mode\n", 2776 QEMU_ARCH_ALL) 2777STEXI 2778@item -qmp @var{dev} 2779@findex -qmp 2780Like -monitor but opens in 'control' mode. 2781ETEXI 2782 2783DEF("mon", HAS_ARG, QEMU_OPTION_mon, \ 2784 "-mon [chardev=]name[,mode=readline|control][,default]\n", QEMU_ARCH_ALL) 2785STEXI 2786@item -mon [chardev=]name[,mode=readline|control][,default] 2787@findex -mon 2788Setup monitor on chardev @var{name}. 2789ETEXI 2790 2791DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ 2792 "-debugcon dev redirect the debug console to char device 'dev'\n", 2793 QEMU_ARCH_ALL) 2794STEXI 2795@item -debugcon @var{dev} 2796@findex -debugcon 2797Redirect the debug console to host device @var{dev} (same devices as the 2798serial port). The debug console is an I/O port which is typically port 27990xe9; writing to that I/O port sends output to this device. 2800The default device is @code{vc} in graphical mode and @code{stdio} in 2801non graphical mode. 2802ETEXI 2803 2804DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ 2805 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL) 2806STEXI 2807@item -pidfile @var{file} 2808@findex -pidfile 2809Store the QEMU process PID in @var{file}. It is useful if you launch QEMU 2810from a script. 2811ETEXI 2812 2813DEF("singlestep", 0, QEMU_OPTION_singlestep, \ 2814 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) 2815STEXI 2816@item -singlestep 2817@findex -singlestep 2818Run the emulation in single step mode. 2819ETEXI 2820 2821DEF("S", 0, QEMU_OPTION_S, \ 2822 "-S freeze CPU at startup (use 'c' to start execution)\n", 2823 QEMU_ARCH_ALL) 2824STEXI 2825@item -S 2826@findex -S 2827Do not start CPU at startup (you must type 'c' in the monitor). 2828ETEXI 2829 2830DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, 2831 "-realtime [mlock=on|off]\n" 2832 " run qemu with realtime features\n" 2833 " mlock=on|off controls mlock support (default: on)\n", 2834 QEMU_ARCH_ALL) 2835STEXI 2836@item -realtime mlock=on|off 2837@findex -realtime 2838Run qemu with realtime features. 2839mlocking qemu and guest memory can be enabled via @option{mlock=on} 2840(enabled by default). 2841ETEXI 2842 2843DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ 2844 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) 2845STEXI 2846@item -gdb @var{dev} 2847@findex -gdb 2848Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical 2849connections will likely be TCP-based, but also UDP, pseudo TTY, or even 2850stdio are reasonable use case. The latter is allowing to start QEMU from 2851within gdb and establish the connection via a pipe: 2852@example 2853(gdb) target remote | exec qemu-system-i386 -gdb stdio ... 2854@end example 2855ETEXI 2856 2857DEF("s", 0, QEMU_OPTION_s, \ 2858 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n", 2859 QEMU_ARCH_ALL) 2860STEXI 2861@item -s 2862@findex -s 2863Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234 2864(@pxref{gdb_usage}). 2865ETEXI 2866 2867DEF("d", HAS_ARG, QEMU_OPTION_d, \ 2868 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n", 2869 QEMU_ARCH_ALL) 2870STEXI 2871@item -d @var{item1}[,...] 2872@findex -d 2873Enable logging of specified items. Use '-d help' for a list of log items. 2874ETEXI 2875 2876DEF("D", HAS_ARG, QEMU_OPTION_D, \ 2877 "-D logfile output log to logfile (default stderr)\n", 2878 QEMU_ARCH_ALL) 2879STEXI 2880@item -D @var{logfile} 2881@findex -D 2882Output log in @var{logfile} instead of to stderr 2883ETEXI 2884 2885DEF("L", HAS_ARG, QEMU_OPTION_L, \ 2886 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", 2887 QEMU_ARCH_ALL) 2888STEXI 2889@item -L @var{path} 2890@findex -L 2891Set the directory for the BIOS, VGA BIOS and keymaps. 2892ETEXI 2893 2894DEF("bios", HAS_ARG, QEMU_OPTION_bios, \ 2895 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL) 2896STEXI 2897@item -bios @var{file} 2898@findex -bios 2899Set the filename for the BIOS. 2900ETEXI 2901 2902DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \ 2903 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL) 2904STEXI 2905@item -enable-kvm 2906@findex -enable-kvm 2907Enable KVM full virtualization support. This option is only available 2908if KVM support is enabled when compiling. 2909ETEXI 2910 2911DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, 2912 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) 2913DEF("xen-create", 0, QEMU_OPTION_xen_create, 2914 "-xen-create create domain using xen hypercalls, bypassing xend\n" 2915 " warning: should not be used when xend is in use\n", 2916 QEMU_ARCH_ALL) 2917DEF("xen-attach", 0, QEMU_OPTION_xen_attach, 2918 "-xen-attach attach to existing xen domain\n" 2919 " xend will use this when starting QEMU\n", 2920 QEMU_ARCH_ALL) 2921STEXI 2922@item -xen-domid @var{id} 2923@findex -xen-domid 2924Specify xen guest domain @var{id} (XEN only). 2925@item -xen-create 2926@findex -xen-create 2927Create domain using xen hypercalls, bypassing xend. 2928Warning: should not be used when xend is in use (XEN only). 2929@item -xen-attach 2930@findex -xen-attach 2931Attach to existing xen domain. 2932xend will use this when starting QEMU (XEN only). 2933ETEXI 2934 2935DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \ 2936 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL) 2937STEXI 2938@item -no-reboot 2939@findex -no-reboot 2940Exit instead of rebooting. 2941ETEXI 2942 2943DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \ 2944 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL) 2945STEXI 2946@item -no-shutdown 2947@findex -no-shutdown 2948Don't exit QEMU on guest shutdown, but instead only stop the emulation. 2949This allows for instance switching to monitor to commit changes to the 2950disk image. 2951ETEXI 2952 2953DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ 2954 "-loadvm [tag|id]\n" \ 2955 " start right away with a saved state (loadvm in monitor)\n", 2956 QEMU_ARCH_ALL) 2957STEXI 2958@item -loadvm @var{file} 2959@findex -loadvm 2960Start right away with a saved state (@code{loadvm} in monitor) 2961ETEXI 2962 2963#ifndef _WIN32 2964DEF("daemonize", 0, QEMU_OPTION_daemonize, \ 2965 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) 2966#endif 2967STEXI 2968@item -daemonize 2969@findex -daemonize 2970Daemonize the QEMU process after initialization. QEMU will not detach from 2971standard IO until it is ready to receive connections on any of its devices. 2972This option is a useful way for external programs to launch QEMU without having 2973to cope with initialization race conditions. 2974ETEXI 2975 2976DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \ 2977 "-option-rom rom load a file, rom, into the option ROM space\n", 2978 QEMU_ARCH_ALL) 2979STEXI 2980@item -option-rom @var{file} 2981@findex -option-rom 2982Load the contents of @var{file} as an option ROM. 2983This option is useful to load things like EtherBoot. 2984ETEXI 2985 2986DEF("clock", HAS_ARG, QEMU_OPTION_clock, \ 2987 "-clock force the use of the given methods for timer alarm.\n" \ 2988 " To see what timers are available use '-clock help'\n", 2989 QEMU_ARCH_ALL) 2990STEXI 2991@item -clock @var{method} 2992@findex -clock 2993Force the use of the given methods for timer alarm. To see what timers 2994are available use @code{-clock help}. 2995ETEXI 2996 2997HXCOMM Options deprecated by -rtc 2998DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL) 2999DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL) 3000 3001DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \ 3002 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \ 3003 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n", 3004 QEMU_ARCH_ALL) 3005 3006STEXI 3007 3008@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew] 3009@findex -rtc 3010Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current 3011UTC or local time, respectively. @code{localtime} is required for correct date in 3012MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the 3013format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC. 3014 3015By default the RTC is driven by the host system time. This allows using of the 3016RTC as accurate reference clock inside the guest, specifically if the host 3017time is smoothly following an accurate external reference clock, e.g. via NTP. 3018If you want to isolate the guest time from the host, you can set @option{clock} 3019to @code{rt} instead. To even prevent it from progressing during suspension, 3020you can set it to @code{vm}. 3021 3022Enable @option{driftfix} (i386 targets only) if you experience time drift problems, 3023specifically with Windows' ACPI HAL. This option will try to figure out how 3024many timer interrupts were not processed by the Windows guest and will 3025re-inject them. 3026ETEXI 3027 3028DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ 3029 "-icount [shift=N|auto][,align=on|off]\n" \ 3030 " enable virtual instruction counter with 2^N clock ticks per\n" \ 3031 " instruction and enable aligning the host and virtual clocks\n", QEMU_ARCH_ALL) 3032STEXI 3033@item -icount [shift=@var{N}|auto] 3034@findex -icount 3035Enable virtual instruction counter. The virtual cpu will execute one 3036instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified 3037then the virtual cpu speed will be automatically adjusted to keep virtual 3038time within a few seconds of real time. 3039 3040Note that while this option can give deterministic behavior, it does not 3041provide cycle accurate emulation. Modern CPUs contain superscalar out of 3042order cores with complex cache hierarchies. The number of instructions 3043executed often has little or no correlation with actual performance. 3044 3045@option{align=on} will activate the delay algorithm which will try to 3046to synchronise the host clock and the virtual clock. The goal is to 3047have a guest running at the real frequency imposed by the shift option. 3048Whenever the guest clock is behind the host clock and if 3049@option{align=on} is specified then we print a messsage to the user 3050to inform about the delay. 3051Currently this option does not work when @option{shift} is @code{auto}. 3052Note: The sync algorithm will work for those shift values for which 3053the guest clock runs ahead of the host clock. Typically this happens 3054when the shift value is high (how high depends on the host machine). 3055ETEXI 3056 3057DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ 3058 "-watchdog i6300esb|ib700\n" \ 3059 " enable virtual hardware watchdog [default=none]\n", 3060 QEMU_ARCH_ALL) 3061STEXI 3062@item -watchdog @var{model} 3063@findex -watchdog 3064Create a virtual hardware watchdog device. Once enabled (by a guest 3065action), the watchdog must be periodically polled by an agent inside 3066the guest or else the guest will be restarted. 3067 3068The @var{model} is the model of hardware watchdog to emulate. Choices 3069for model are: @code{ib700} (iBASE 700) which is a very simple ISA 3070watchdog with a single timer, or @code{i6300esb} (Intel 6300ESB I/O 3071controller hub) which is a much more featureful PCI-based dual-timer 3072watchdog. Choose a model for which your guest has drivers. 3073 3074Use @code{-watchdog help} to list available hardware models. Only one 3075watchdog can be enabled for a guest. 3076ETEXI 3077 3078DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \ 3079 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \ 3080 " action when watchdog fires [default=reset]\n", 3081 QEMU_ARCH_ALL) 3082STEXI 3083@item -watchdog-action @var{action} 3084@findex -watchdog-action 3085 3086The @var{action} controls what QEMU will do when the watchdog timer 3087expires. 3088The default is 3089@code{reset} (forcefully reset the guest). 3090Other possible actions are: 3091@code{shutdown} (attempt to gracefully shutdown the guest), 3092@code{poweroff} (forcefully poweroff the guest), 3093@code{pause} (pause the guest), 3094@code{debug} (print a debug message and continue), or 3095@code{none} (do nothing). 3096 3097Note that the @code{shutdown} action requires that the guest responds 3098to ACPI signals, which it may not be able to do in the sort of 3099situations where the watchdog would have expired, and thus 3100@code{-watchdog-action shutdown} is not recommended for production use. 3101 3102Examples: 3103 3104@table @code 3105@item -watchdog i6300esb -watchdog-action pause 3106@item -watchdog ib700 3107@end table 3108ETEXI 3109 3110DEF("echr", HAS_ARG, QEMU_OPTION_echr, \ 3111 "-echr chr set terminal escape character instead of ctrl-a\n", 3112 QEMU_ARCH_ALL) 3113STEXI 3114 3115@item -echr @var{numeric_ascii_value} 3116@findex -echr 3117Change the escape character used for switching to the monitor when using 3118monitor and serial sharing. The default is @code{0x01} when using the 3119@code{-nographic} option. @code{0x01} is equal to pressing 3120@code{Control-a}. You can select a different character from the ascii 3121control keys where 1 through 26 map to Control-a through Control-z. For 3122instance you could use the either of the following to change the escape 3123character to Control-t. 3124@table @code 3125@item -echr 0x14 3126@item -echr 20 3127@end table 3128ETEXI 3129 3130DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \ 3131 "-virtioconsole c\n" \ 3132 " set virtio console\n", QEMU_ARCH_ALL) 3133STEXI 3134@item -virtioconsole @var{c} 3135@findex -virtioconsole 3136Set virtio console. 3137 3138This option is maintained for backward compatibility. 3139 3140Please use @code{-device virtconsole} for the new way of invocation. 3141ETEXI 3142 3143DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \ 3144 "-show-cursor show cursor\n", QEMU_ARCH_ALL) 3145STEXI 3146@item -show-cursor 3147@findex -show-cursor 3148Show cursor. 3149ETEXI 3150 3151DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \ 3152 "-tb-size n set TB size\n", QEMU_ARCH_ALL) 3153STEXI 3154@item -tb-size @var{n} 3155@findex -tb-size 3156Set TB size. 3157ETEXI 3158 3159DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \ 3160 "-incoming p prepare for incoming migration, listen on port p\n", 3161 QEMU_ARCH_ALL) 3162STEXI 3163@item -incoming @var{port} 3164@findex -incoming 3165Prepare for incoming migration, listen on @var{port}. 3166ETEXI 3167 3168DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \ 3169 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL) 3170STEXI 3171@item -nodefaults 3172@findex -nodefaults 3173Don't create default devices. Normally, QEMU sets the default devices like serial 3174port, parallel port, virtual console, monitor device, VGA adapter, floppy and 3175CD-ROM drive and others. The @code{-nodefaults} option will disable all those 3176default devices. 3177ETEXI 3178 3179#ifndef _WIN32 3180DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \ 3181 "-chroot dir chroot to dir just before starting the VM\n", 3182 QEMU_ARCH_ALL) 3183#endif 3184STEXI 3185@item -chroot @var{dir} 3186@findex -chroot 3187Immediately before starting guest execution, chroot to the specified 3188directory. Especially useful in combination with -runas. 3189ETEXI 3190 3191#ifndef _WIN32 3192DEF("runas", HAS_ARG, QEMU_OPTION_runas, \ 3193 "-runas user change to user id user just before starting the VM\n", 3194 QEMU_ARCH_ALL) 3195#endif 3196STEXI 3197@item -runas @var{user} 3198@findex -runas 3199Immediately before starting guest execution, drop root privileges, switching 3200to the specified user. 3201ETEXI 3202 3203DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env, 3204 "-prom-env variable=value\n" 3205 " set OpenBIOS nvram variables\n", 3206 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 3207STEXI 3208@item -prom-env @var{variable}=@var{value} 3209@findex -prom-env 3210Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only). 3211ETEXI 3212DEF("semihosting", 0, QEMU_OPTION_semihosting, 3213 "-semihosting semihosting mode\n", 3214 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32) 3215STEXI 3216@item -semihosting 3217@findex -semihosting 3218Semihosting mode (ARM, M68K, Xtensa only). 3219ETEXI 3220DEF("old-param", 0, QEMU_OPTION_old_param, 3221 "-old-param old param mode\n", QEMU_ARCH_ARM) 3222STEXI 3223@item -old-param 3224@findex -old-param (ARM) 3225Old param mode (ARM only). 3226ETEXI 3227 3228DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ 3229 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n", 3230 QEMU_ARCH_ALL) 3231STEXI 3232@item -sandbox @var{arg} 3233@findex -sandbox 3234Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will 3235disable it. The default is 'off'. 3236ETEXI 3237 3238DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, 3239 "-readconfig <file>\n", QEMU_ARCH_ALL) 3240STEXI 3241@item -readconfig @var{file} 3242@findex -readconfig 3243Read device configuration from @var{file}. This approach is useful when you want to spawn 3244QEMU process with many command line options but you don't want to exceed the command line 3245character limit. 3246ETEXI 3247DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig, 3248 "-writeconfig <file>\n" 3249 " read/write config file\n", QEMU_ARCH_ALL) 3250STEXI 3251@item -writeconfig @var{file} 3252@findex -writeconfig 3253Write device configuration to @var{file}. The @var{file} can be either filename to save 3254command line and device configuration into file or dash @code{-}) character to print the 3255output to stdout. This can be later used as input file for @code{-readconfig} option. 3256ETEXI 3257DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, 3258 "-nodefconfig\n" 3259 " do not load default config files at startup\n", 3260 QEMU_ARCH_ALL) 3261STEXI 3262@item -nodefconfig 3263@findex -nodefconfig 3264Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup. 3265The @code{-nodefconfig} option will prevent QEMU from loading any of those config files. 3266ETEXI 3267DEF("no-user-config", 0, QEMU_OPTION_nouserconfig, 3268 "-no-user-config\n" 3269 " do not load user-provided config files at startup\n", 3270 QEMU_ARCH_ALL) 3271STEXI 3272@item -no-user-config 3273@findex -no-user-config 3274The @code{-no-user-config} option makes QEMU not load any of the user-provided 3275config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config 3276files from @var{datadir}. 3277ETEXI 3278DEF("trace", HAS_ARG, QEMU_OPTION_trace, 3279 "-trace [events=<file>][,file=<file>]\n" 3280 " specify tracing options\n", 3281 QEMU_ARCH_ALL) 3282STEXI 3283HXCOMM This line is not accurate, as some sub-options are backend-specific but 3284HXCOMM HX does not support conditional compilation of text. 3285@item -trace [events=@var{file}][,file=@var{file}] 3286@findex -trace 3287 3288Specify tracing options. 3289 3290@table @option 3291@item events=@var{file} 3292Immediately enable events listed in @var{file}. 3293The file must contain one event name (as listed in the @var{trace-events} file) 3294per line. 3295This option is only available if QEMU has been compiled with 3296either @var{simple} or @var{stderr} tracing backend. 3297@item file=@var{file} 3298Log output traces to @var{file}. 3299 3300This option is only available if QEMU has been compiled with 3301the @var{simple} tracing backend. 3302@end table 3303ETEXI 3304 3305HXCOMM Internal use 3306DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL) 3307DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL) 3308 3309#ifdef __linux__ 3310DEF("enable-fips", 0, QEMU_OPTION_enablefips, 3311 "-enable-fips enable FIPS 140-2 compliance\n", 3312 QEMU_ARCH_ALL) 3313#endif 3314STEXI 3315@item -enable-fips 3316@findex -enable-fips 3317Enable FIPS 140-2 compliance mode. 3318ETEXI 3319 3320HXCOMM Deprecated by -machine accel=tcg property 3321DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386) 3322 3323HXCOMM Deprecated by kvm-pit driver properties 3324DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection, 3325 "", QEMU_ARCH_I386) 3326 3327HXCOMM Deprecated (ignored) 3328DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386) 3329 3330HXCOMM Deprecated by -machine kernel_irqchip=on|off property 3331DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386) 3332 3333HXCOMM Deprecated (ignored) 3334DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL) 3335 3336DEF("object", HAS_ARG, QEMU_OPTION_object, 3337 "-object TYPENAME[,PROP1=VALUE1,...]\n" 3338 " create an new object of type TYPENAME setting properties\n" 3339 " in the order they are specified. Note that the 'id'\n" 3340 " property must be set. These objects are placed in the\n" 3341 " '/objects' path.\n", 3342 QEMU_ARCH_ALL) 3343STEXI 3344@item -object @var{typename}[,@var{prop1}=@var{value1},...] 3345@findex -object 3346Create an new object of type @var{typename} setting properties 3347in the order they are specified. Note that the 'id' 3348property must be set. These objects are placed in the 3349'/objects' path. 3350ETEXI 3351 3352DEF("msg", HAS_ARG, QEMU_OPTION_msg, 3353 "-msg timestamp[=on|off]\n" 3354 " change the format of messages\n" 3355 " on|off controls leading timestamps (default:on)\n", 3356 QEMU_ARCH_ALL) 3357STEXI 3358@item -msg timestamp[=on|off] 3359@findex -msg 3360prepend a timestamp to each log message.(default:on) 3361ETEXI 3362 3363DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate, 3364 "-dump-vmstate <file>\n" 3365 " Output vmstate information in JSON format to file.\n" 3366 " Use the scripts/vmstate-static-checker.py file to\n" 3367 " check for possible regressions in migration code\n" 3368 " by comparing two such vmstate dumps.", 3369 QEMU_ARCH_ALL) 3370STEXI 3371@item -dump-vmstate @var{file} 3372@findex -dump-vmstate 3373Dump json-encoded vmstate information for current machine type to file 3374in @var{file} 3375ETEXI 3376 3377HXCOMM This is the last statement. Insert new options before this line! 3378STEXI 3379@end table 3380ETEXI 3381
