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 QEMU_ARCH_ALL) 40STEXI 41@item -machine [type=]@var{name}[,prop=@var{value}[,...]] 42@findex -machine 43Select the emulated machine by @var{name}. Use @code{-machine help} to list 44available machines. Supported machine properties are: 45@table @option 46@item accel=@var{accels1}[:@var{accels2}[:...]] 47This is used to enable an accelerator. Depending on the target architecture, 48kvm, xen, or tcg can be available. By default, tcg is used. If there is more 49than one accelerator specified, the next one is used if the previous one fails 50to initialize. 51@item kernel_irqchip=on|off 52Enables in-kernel irqchip support for the chosen accelerator when available. 53@item kvm_shadow_mem=size 54Defines the size of the KVM shadow MMU. 55@item dump-guest-core=on|off 56Include guest memory in a core dump. The default is on. 57@item mem-merge=on|off 58Enables or disables memory merge support. This feature, when supported by 59the host, de-duplicates identical memory pages among VMs instances 60(enabled by default). 61@end table 62ETEXI 63 64HXCOMM Deprecated by -machine 65DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL) 66 67DEF("cpu", HAS_ARG, QEMU_OPTION_cpu, 68 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL) 69STEXI 70@item -cpu @var{model} 71@findex -cpu 72Select CPU model (@code{-cpu help} for list and additional feature selection) 73ETEXI 74 75DEF("smp", HAS_ARG, QEMU_OPTION_smp, 76 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n" 77 " set the number of CPUs to 'n' [default=1]\n" 78 " maxcpus= maximum number of total cpus, including\n" 79 " offline CPUs for hotplug, etc\n" 80 " cores= number of CPU cores on one socket\n" 81 " threads= number of threads on one CPU core\n" 82 " sockets= number of discrete sockets in the system\n", 83 QEMU_ARCH_ALL) 84STEXI 85@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}] 86@findex -smp 87Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255 88CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs 89to 4. 90For the PC target, the number of @var{cores} per socket, the number 91of @var{threads} per cores and the total number of @var{sockets} can be 92specified. Missing values will be computed. If any on the three values is 93given, the total number of CPUs @var{n} can be omitted. @var{maxcpus} 94specifies the maximum number of hotpluggable CPUs. 95ETEXI 96 97DEF("numa", HAS_ARG, QEMU_OPTION_numa, 98 "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n" 99 "-numa node[,memdev=id][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL) 100STEXI 101@item -numa node[,mem=@var{size}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}] 102@item -numa node[,memdev=@var{id}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}] 103@findex -numa 104Simulate a multi node NUMA system. If @samp{mem}, @samp{memdev} 105and @samp{cpus} are omitted, resources are split equally. Also, note 106that the -@option{numa} option doesn't allocate any of the specified 107resources. That is, it just assigns existing resources to NUMA nodes. This 108means that one still has to use the @option{-m}, @option{-smp} options 109to allocate RAM and VCPUs respectively, and possibly @option{-object} 110to specify the memory backend for the @samp{memdev} suboption. 111 112@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, if one 113node uses @samp{memdev}, all of them have to use it. 114ETEXI 115 116DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd, 117 "-add-fd fd=fd,set=set[,opaque=opaque]\n" 118 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL) 119STEXI 120@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}] 121@findex -add-fd 122 123Add a file descriptor to an fd set. Valid options are: 124 125@table @option 126@item fd=@var{fd} 127This option defines the file descriptor of which a duplicate is added to fd set. 128The file descriptor cannot be stdin, stdout, or stderr. 129@item set=@var{set} 130This option defines the ID of the fd set to add the file descriptor to. 131@item opaque=@var{opaque} 132This option defines a free-form string that can be used to describe @var{fd}. 133@end table 134 135You can open an image using pre-opened file descriptors from an fd set: 136@example 137qemu-system-i386 138-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 139-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 140-drive file=/dev/fdset/2,index=0,media=disk 141@end example 142ETEXI 143 144DEF("set", HAS_ARG, QEMU_OPTION_set, 145 "-set group.id.arg=value\n" 146 " set <arg> parameter for item <id> of type <group>\n" 147 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL) 148STEXI 149@item -set @var{group}.@var{id}.@var{arg}=@var{value} 150@findex -set 151Set parameter @var{arg} for item @var{id} of type @var{group}\n" 152ETEXI 153 154DEF("global", HAS_ARG, QEMU_OPTION_global, 155 "-global driver.prop=value\n" 156 " set a global default for a driver property\n", 157 QEMU_ARCH_ALL) 158STEXI 159@item -global @var{driver}.@var{prop}=@var{value} 160@findex -global 161Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.: 162 163@example 164qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk 165@end example 166 167In particular, you can use this to set driver properties for devices which are 168created automatically by the machine model. To create a device which is not 169created automatically and set properties on it, use -@option{device}. 170ETEXI 171 172DEF("boot", HAS_ARG, QEMU_OPTION_boot, 173 "-boot [order=drives][,once=drives][,menu=on|off]\n" 174 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n" 175 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n" 176 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n" 177 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n" 178 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n", 179 QEMU_ARCH_ALL) 180STEXI 181@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] 182@findex -boot 183Specify boot order @var{drives} as a string of drive letters. Valid 184drive letters depend on the target achitecture. The x86 PC uses: a, b 185(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot 186from network adapter 1-4), hard disk boot is the default. To apply a 187particular boot order only on the first startup, specify it via 188@option{once}. 189 190Interactive boot menus/prompts can be enabled via @option{menu=on} as far 191as firmware/BIOS supports them. The default is non-interactive boot. 192 193A splash picture could be passed to bios, enabling user to show it as logo, 194when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS 195supports them. Currently Seabios for X86 system support it. 196limitation: The splash file could be a jpeg file or a BMP file in 24 BPP 197format(true color). The resolution should be supported by the SVGA mode, so 198the recommended is 320x240, 640x480, 800x640. 199 200A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms 201when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not 202reboot, qemu passes '-1' to bios by default. Currently Seabios for X86 203system support it. 204 205Do strict boot via @option{strict=on} as far as firmware/BIOS 206supports it. This only effects when boot priority is changed by 207bootindex options. The default is non-strict boot. 208 209@example 210# try to boot from network first, then from hard disk 211qemu-system-i386 -boot order=nc 212# boot from CD-ROM first, switch back to default order after reboot 213qemu-system-i386 -boot once=d 214# boot with a splash picture for 5 seconds. 215qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000 216@end example 217 218Note: The legacy format '-boot @var{drives}' is still supported but its 219use is discouraged as it may be removed from future versions. 220ETEXI 221 222DEF("m", HAS_ARG, QEMU_OPTION_m, 223 "-m[emory] [size=]megs[,slots=n,maxmem=size]\n" 224 " configure guest RAM\n" 225 " size: initial amount of guest memory (default: " 226 stringify(DEFAULT_RAM_SIZE) "MiB)\n" 227 " slots: number of hotplug slots (default: none)\n" 228 " maxmem: maximum amount of guest memory (default: none)\n", 229 QEMU_ARCH_ALL) 230STEXI 231@item -m [size=]@var{megs} 232@findex -m 233Set virtual RAM size to @var{megs} megabytes. Default is 128 MiB. Optionally, 234a suffix of ``M'' or ``G'' can be used to signify a value in megabytes or 235gigabytes respectively. Optional pair @var{slots}, @var{maxmem} could be used 236to set amount of hotluggable memory slots and possible maximum amount of memory. 237ETEXI 238 239DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath, 240 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL) 241STEXI 242@item -mem-path @var{path} 243@findex -mem-path 244Allocate guest RAM from a temporarily created file in @var{path}. 245ETEXI 246 247DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc, 248 "-mem-prealloc preallocate guest memory (use with -mem-path)\n", 249 QEMU_ARCH_ALL) 250STEXI 251@item -mem-prealloc 252@findex -mem-prealloc 253Preallocate memory when using -mem-path. 254ETEXI 255 256DEF("k", HAS_ARG, QEMU_OPTION_k, 257 "-k language use keyboard layout (for example 'fr' for French)\n", 258 QEMU_ARCH_ALL) 259STEXI 260@item -k @var{language} 261@findex -k 262Use keyboard layout @var{language} (for example @code{fr} for 263French). This option is only needed where it is not easy to get raw PC 264keycodes (e.g. on Macs, with some X11 servers or with a VNC 265display). You don't normally need to use it on PC/Linux or PC/Windows 266hosts. 267 268The available layouts are: 269@example 270ar de-ch es fo fr-ca hu ja mk no pt-br sv 271da en-gb et fr fr-ch is lt nl pl ru th 272de en-us fi fr-be hr it lv nl-be pt sl tr 273@end example 274 275The default is @code{en-us}. 276ETEXI 277 278 279DEF("audio-help", 0, QEMU_OPTION_audio_help, 280 "-audio-help print list of audio drivers and their options\n", 281 QEMU_ARCH_ALL) 282STEXI 283@item -audio-help 284@findex -audio-help 285Will show the audio subsystem help: list of drivers, tunable 286parameters. 287ETEXI 288 289DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw, 290 "-soundhw c1,... enable audio support\n" 291 " and only specified sound cards (comma separated list)\n" 292 " use '-soundhw help' to get the list of supported cards\n" 293 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL) 294STEXI 295@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all 296@findex -soundhw 297Enable audio and selected sound hardware. Use 'help' to print all 298available sound hardware. 299 300@example 301qemu-system-i386 -soundhw sb16,adlib disk.img 302qemu-system-i386 -soundhw es1370 disk.img 303qemu-system-i386 -soundhw ac97 disk.img 304qemu-system-i386 -soundhw hda disk.img 305qemu-system-i386 -soundhw all disk.img 306qemu-system-i386 -soundhw help 307@end example 308 309Note that Linux's i810_audio OSS kernel (for AC97) module might 310require manually specifying clocking. 311 312@example 313modprobe i810_audio clocking=48000 314@end example 315ETEXI 316 317DEF("balloon", HAS_ARG, QEMU_OPTION_balloon, 318 "-balloon none disable balloon device\n" 319 "-balloon virtio[,addr=str]\n" 320 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL) 321STEXI 322@item -balloon none 323@findex -balloon 324Disable balloon device. 325@item -balloon virtio[,addr=@var{addr}] 326Enable virtio balloon device (default), optionally with PCI address 327@var{addr}. 328ETEXI 329 330DEF("device", HAS_ARG, QEMU_OPTION_device, 331 "-device driver[,prop[=value][,...]]\n" 332 " add device (based on driver)\n" 333 " prop=value,... sets driver properties\n" 334 " use '-device help' to print all possible drivers\n" 335 " use '-device driver,help' to print all possible properties\n", 336 QEMU_ARCH_ALL) 337STEXI 338@item -device @var{driver}[,@var{prop}[=@var{value}][,...]] 339@findex -device 340Add device @var{driver}. @var{prop}=@var{value} sets driver 341properties. Valid properties depend on the driver. To get help on 342possible drivers and properties, use @code{-device help} and 343@code{-device @var{driver},help}. 344ETEXI 345 346DEF("name", HAS_ARG, QEMU_OPTION_name, 347 "-name string1[,process=string2][,debug-threads=on|off]\n" 348 " set the name of the guest\n" 349 " string1 sets the window title and string2 the process name (on Linux)\n" 350 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n" 351 " NOTE: The thread names are for debugging and not a stable API.\n", 352 QEMU_ARCH_ALL) 353STEXI 354@item -name @var{name} 355@findex -name 356Sets the @var{name} of the guest. 357This name will be displayed in the SDL window caption. 358The @var{name} will also be used for the VNC server. 359Also optionally set the top visible process name in Linux. 360Naming of individual threads can also be enabled on Linux to aid debugging. 361ETEXI 362 363DEF("uuid", HAS_ARG, QEMU_OPTION_uuid, 364 "-uuid %08x-%04x-%04x-%04x-%012x\n" 365 " specify machine UUID\n", QEMU_ARCH_ALL) 366STEXI 367@item -uuid @var{uuid} 368@findex -uuid 369Set system UUID. 370ETEXI 371 372STEXI 373@end table 374ETEXI 375DEFHEADING() 376 377DEFHEADING(Block device options:) 378STEXI 379@table @option 380ETEXI 381 382DEF("fda", HAS_ARG, QEMU_OPTION_fda, 383 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL) 384DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL) 385STEXI 386@item -fda @var{file} 387@item -fdb @var{file} 388@findex -fda 389@findex -fdb 390Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). You can 391use the host floppy by using @file{/dev/fd0} as filename (@pxref{host_drives}). 392ETEXI 393 394DEF("hda", HAS_ARG, QEMU_OPTION_hda, 395 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL) 396DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL) 397DEF("hdc", HAS_ARG, QEMU_OPTION_hdc, 398 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL) 399DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL) 400STEXI 401@item -hda @var{file} 402@item -hdb @var{file} 403@item -hdc @var{file} 404@item -hdd @var{file} 405@findex -hda 406@findex -hdb 407@findex -hdc 408@findex -hdd 409Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}). 410ETEXI 411 412DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom, 413 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n", 414 QEMU_ARCH_ALL) 415STEXI 416@item -cdrom @var{file} 417@findex -cdrom 418Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and 419@option{-cdrom} at the same time). You can use the host CD-ROM by 420using @file{/dev/cdrom} as filename (@pxref{host_drives}). 421ETEXI 422 423DEF("drive", HAS_ARG, QEMU_OPTION_drive, 424 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" 425 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n" 426 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n" 427 " [,serial=s][,addr=A][,rerror=ignore|stop|report]\n" 428 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n" 429 " [,readonly=on|off][,copy-on-read=on|off]\n" 430 " [,detect-zeroes=on|off|unmap]\n" 431 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n" 432 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n" 433 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n" 434 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n" 435 " [[,iops_size=is]]\n" 436 " use 'file' as a drive image\n", QEMU_ARCH_ALL) 437STEXI 438@item -drive @var{option}[,@var{option}[,@var{option}[,...]]] 439@findex -drive 440 441Define a new drive. Valid options are: 442 443@table @option 444@item file=@var{file} 445This option defines which disk image (@pxref{disk_images}) to use with 446this drive. If the filename contains comma, you must double it 447(for instance, "file=my,,file" to use file "my,file"). 448 449Special files such as iSCSI devices can be specified using protocol 450specific URLs. See the section for "Device URL Syntax" for more information. 451@item if=@var{interface} 452This option defines on which type on interface the drive is connected. 453Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio. 454@item bus=@var{bus},unit=@var{unit} 455These options define where is connected the drive by defining the bus number and 456the unit id. 457@item index=@var{index} 458This option defines where is connected the drive by using an index in the list 459of available connectors of a given interface type. 460@item media=@var{media} 461This option defines the type of the media: disk or cdrom. 462@item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}] 463These options have the same definition as they have in @option{-hdachs}. 464@item snapshot=@var{snapshot} 465@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive 466(see @option{-snapshot}). 467@item cache=@var{cache} 468@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data. 469@item aio=@var{aio} 470@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO. 471@item discard=@var{discard} 472@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. 473@item format=@var{format} 474Specify which disk @var{format} will be used rather than detecting 475the format. Can be used to specifiy format=raw to avoid interpreting 476an untrusted format header. 477@item serial=@var{serial} 478This option specifies the serial number to assign to the device. 479@item addr=@var{addr} 480Specify the controller's PCI address (if=virtio only). 481@item werror=@var{action},rerror=@var{action} 482Specify which @var{action} to take on write and read errors. Valid actions are: 483"ignore" (ignore the error and try to continue), "stop" (pause QEMU), 484"report" (report the error to the guest), "enospc" (pause QEMU only if the 485host disk is full; report the error to the guest otherwise). 486The default setting is @option{werror=enospc} and @option{rerror=report}. 487@item readonly 488Open drive @option{file} as read-only. Guest write attempts will fail. 489@item copy-on-read=@var{copy-on-read} 490@var{copy-on-read} is "on" or "off" and enables whether to copy read backing 491file sectors into the image file. 492@item detect-zeroes=@var{detect-zeroes} 493@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic 494conversion of plain zero writes by the OS to driver specific optimized 495zero write commands. You may even choose "unmap" if @var{discard} is set 496to "unmap" to allow a zero write to be converted to an UNMAP operation. 497@end table 498 499By default, the @option{cache=writeback} mode is used. It will report data 500writes as completed as soon as the data is present in the host page cache. 501This is safe as long as your guest OS makes sure to correctly flush disk caches 502where needed. If your guest OS does not handle volatile disk write caches 503correctly and your host crashes or loses power, then the guest may experience 504data corruption. 505 506For such guests, you should consider using @option{cache=writethrough}. This 507means that the host page cache will be used to read and write data, but write 508notification will be sent to the guest only after QEMU has made sure to flush 509each write to the disk. Be aware that this has a major impact on performance. 510 511The host page cache can be avoided entirely with @option{cache=none}. This will 512attempt to do disk IO directly to the guest's memory. QEMU may still perform 513an internal copy of the data. Note that this is considered a writeback mode and 514the guest OS must handle the disk write cache correctly in order to avoid data 515corruption on host crashes. 516 517The host page cache can be avoided while only sending write notifications to 518the guest when the data has been flushed to the disk using 519@option{cache=directsync}. 520 521In case you don't care about data integrity over host failures, use 522@option{cache=unsafe}. This option tells QEMU that it never needs to write any 523data to the disk but can instead keep things in cache. If anything goes wrong, 524like your host losing power, the disk storage getting disconnected accidentally, 525etc. your image will most probably be rendered unusable. When using 526the @option{-snapshot} option, unsafe caching is always used. 527 528Copy-on-read avoids accessing the same backing file sectors repeatedly and is 529useful when the backing file is over a slow network. By default copy-on-read 530is off. 531 532Instead of @option{-cdrom} you can use: 533@example 534qemu-system-i386 -drive file=file,index=2,media=cdrom 535@end example 536 537Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can 538use: 539@example 540qemu-system-i386 -drive file=file,index=0,media=disk 541qemu-system-i386 -drive file=file,index=1,media=disk 542qemu-system-i386 -drive file=file,index=2,media=disk 543qemu-system-i386 -drive file=file,index=3,media=disk 544@end example 545 546You can open an image using pre-opened file descriptors from an fd set: 547@example 548qemu-system-i386 549-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 550-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 551-drive file=/dev/fdset/2,index=0,media=disk 552@end example 553 554You can connect a CDROM to the slave of ide0: 555@example 556qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom 557@end example 558 559If you don't specify the "file=" argument, you define an empty drive: 560@example 561qemu-system-i386 -drive if=ide,index=1,media=cdrom 562@end example 563 564You can connect a SCSI disk with unit ID 6 on the bus #0: 565@example 566qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6 567@end example 568 569Instead of @option{-fda}, @option{-fdb}, you can use: 570@example 571qemu-system-i386 -drive file=file,index=0,if=floppy 572qemu-system-i386 -drive file=file,index=1,if=floppy 573@end example 574 575By default, @var{interface} is "ide" and @var{index} is automatically 576incremented: 577@example 578qemu-system-i386 -drive file=a -drive file=b" 579@end example 580is interpreted like: 581@example 582qemu-system-i386 -hda a -hdb b 583@end example 584ETEXI 585 586DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock, 587 "-mtdblock file use 'file' as on-board Flash memory image\n", 588 QEMU_ARCH_ALL) 589STEXI 590@item -mtdblock @var{file} 591@findex -mtdblock 592Use @var{file} as on-board Flash memory image. 593ETEXI 594 595DEF("sd", HAS_ARG, QEMU_OPTION_sd, 596 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL) 597STEXI 598@item -sd @var{file} 599@findex -sd 600Use @var{file} as SecureDigital card image. 601ETEXI 602 603DEF("pflash", HAS_ARG, QEMU_OPTION_pflash, 604 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL) 605STEXI 606@item -pflash @var{file} 607@findex -pflash 608Use @var{file} as a parallel flash image. 609ETEXI 610 611DEF("snapshot", 0, QEMU_OPTION_snapshot, 612 "-snapshot write to temporary files instead of disk image files\n", 613 QEMU_ARCH_ALL) 614STEXI 615@item -snapshot 616@findex -snapshot 617Write to temporary files instead of disk image files. In this case, 618the raw disk image you use is not written back. You can however force 619the write back by pressing @key{C-a s} (@pxref{disk_images}). 620ETEXI 621 622DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \ 623 "-hdachs c,h,s[,t]\n" \ 624 " force hard disk 0 physical geometry and the optional BIOS\n" \ 625 " translation (t=none or lba) (usually QEMU can guess them)\n", 626 QEMU_ARCH_ALL) 627STEXI 628@item -hdachs @var{c},@var{h},@var{s},[,@var{t}] 629@findex -hdachs 630Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <= 631@var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS 632translation mode (@var{t}=none, lba or auto). Usually QEMU can guess 633all those parameters. This option is useful for old MS-DOS disk 634images. 635ETEXI 636 637DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev, 638 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n" 639 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n", 640 QEMU_ARCH_ALL) 641 642STEXI 643 644@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}] 645@findex -fsdev 646Define a new file system device. Valid options are: 647@table @option 648@item @var{fsdriver} 649This option specifies the fs driver backend to use. 650Currently "local", "handle" and "proxy" file system drivers are supported. 651@item id=@var{id} 652Specifies identifier for this device 653@item path=@var{path} 654Specifies the export path for the file system device. Files under 655this path will be available to the 9p client on the guest. 656@item security_model=@var{security_model} 657Specifies the security model to be used for this export path. 658Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 659In "passthrough" security model, files are stored using the same 660credentials as they are created on the guest. This requires QEMU 661to run as root. In "mapped-xattr" security model, some of the file 662attributes like uid, gid, mode bits and link target are stored as 663file attributes. For "mapped-file" these attributes are stored in the 664hidden .virtfs_metadata directory. Directories exported by this security model cannot 665interact with other unix tools. "none" security model is same as 666passthrough except the sever won't report failures if it fails to 667set file attributes like ownership. Security model is mandatory 668only for local fsdriver. Other fsdrivers (like handle, proxy) don't take 669security model as a parameter. 670@item writeout=@var{writeout} 671This is an optional argument. The only supported value is "immediate". 672This means that host page cache will be used to read and write data but 673write notification will be sent to the guest only when the data has been 674reported as written by the storage subsystem. 675@item readonly 676Enables exporting 9p share as a readonly mount for guests. By default 677read-write access is given. 678@item socket=@var{socket} 679Enables proxy filesystem driver to use passed socket file for communicating 680with virtfs-proxy-helper 681@item sock_fd=@var{sock_fd} 682Enables proxy filesystem driver to use passed socket descriptor for 683communicating with virtfs-proxy-helper. Usually a helper like libvirt 684will create socketpair and pass one of the fds as sock_fd 685@end table 686 687-fsdev option is used along with -device driver "virtio-9p-pci". 688@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag} 689Options for virtio-9p-pci driver are: 690@table @option 691@item fsdev=@var{id} 692Specifies the id value specified along with -fsdev option 693@item mount_tag=@var{mount_tag} 694Specifies the tag name to be used by the guest to mount this export point 695@end table 696 697ETEXI 698 699DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs, 700 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n" 701 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n", 702 QEMU_ARCH_ALL) 703 704STEXI 705 706@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}] 707@findex -virtfs 708 709The general form of a Virtual File system pass-through options are: 710@table @option 711@item @var{fsdriver} 712This option specifies the fs driver backend to use. 713Currently "local", "handle" and "proxy" file system drivers are supported. 714@item id=@var{id} 715Specifies identifier for this device 716@item path=@var{path} 717Specifies the export path for the file system device. Files under 718this path will be available to the 9p client on the guest. 719@item security_model=@var{security_model} 720Specifies the security model to be used for this export path. 721Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 722In "passthrough" security model, files are stored using the same 723credentials as they are created on the guest. This requires QEMU 724to run as root. In "mapped-xattr" security model, some of the file 725attributes like uid, gid, mode bits and link target are stored as 726file attributes. For "mapped-file" these attributes are stored in the 727hidden .virtfs_metadata directory. Directories exported by this security model cannot 728interact with other unix tools. "none" security model is same as 729passthrough except the sever won't report failures if it fails to 730set file attributes like ownership. Security model is mandatory only 731for local fsdriver. Other fsdrivers (like handle, proxy) don't take security 732model as a parameter. 733@item writeout=@var{writeout} 734This is an optional argument. The only supported value is "immediate". 735This means that host page cache will be used to read and write data but 736write notification will be sent to the guest only when the data has been 737reported as written by the storage subsystem. 738@item readonly 739Enables exporting 9p share as a readonly mount for guests. By default 740read-write access is given. 741@item socket=@var{socket} 742Enables proxy filesystem driver to use passed socket file for 743communicating with virtfs-proxy-helper. Usually a helper like libvirt 744will create socketpair and pass one of the fds as sock_fd 745@item sock_fd 746Enables proxy filesystem driver to use passed 'sock_fd' as the socket 747descriptor for interfacing with virtfs-proxy-helper 748@end table 749ETEXI 750 751DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth, 752 "-virtfs_synth Create synthetic file system image\n", 753 QEMU_ARCH_ALL) 754STEXI 755@item -virtfs_synth 756@findex -virtfs_synth 757Create synthetic file system image 758ETEXI 759 760STEXI 761@end table 762ETEXI 763DEFHEADING() 764 765DEFHEADING(USB options:) 766STEXI 767@table @option 768ETEXI 769 770DEF("usb", 0, QEMU_OPTION_usb, 771 "-usb enable the USB driver (will be the default soon)\n", 772 QEMU_ARCH_ALL) 773STEXI 774@item -usb 775@findex -usb 776Enable the USB driver (will be the default soon) 777ETEXI 778 779DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice, 780 "-usbdevice name add the host or guest USB device 'name'\n", 781 QEMU_ARCH_ALL) 782STEXI 783 784@item -usbdevice @var{devname} 785@findex -usbdevice 786Add the USB device @var{devname}. @xref{usb_devices}. 787 788@table @option 789 790@item mouse 791Virtual Mouse. This will override the PS/2 mouse emulation when activated. 792 793@item tablet 794Pointer device that uses absolute coordinates (like a touchscreen). This 795means QEMU is able to report the mouse position without having to grab the 796mouse. Also overrides the PS/2 mouse emulation when activated. 797 798@item disk:[format=@var{format}]:@var{file} 799Mass storage device based on file. The optional @var{format} argument 800will be used rather than detecting the format. Can be used to specifiy 801@code{format=raw} to avoid interpreting an untrusted format header. 802 803@item host:@var{bus}.@var{addr} 804Pass through the host device identified by @var{bus}.@var{addr} (Linux only). 805 806@item host:@var{vendor_id}:@var{product_id} 807Pass through the host device identified by @var{vendor_id}:@var{product_id} 808(Linux only). 809 810@item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev} 811Serial converter to host character device @var{dev}, see @code{-serial} for the 812available devices. 813 814@item braille 815Braille device. This will use BrlAPI to display the braille output on a real 816or fake device. 817 818@item net:@var{options} 819Network adapter that supports CDC ethernet and RNDIS protocols. 820 821@end table 822ETEXI 823 824STEXI 825@end table 826ETEXI 827DEFHEADING() 828 829DEFHEADING(Display options:) 830STEXI 831@table @option 832ETEXI 833 834DEF("display", HAS_ARG, QEMU_OPTION_display, 835 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n" 836 " [,window_close=on|off]|curses|none|\n" 837 " gtk[,grab_on_hover=on|off]|\n" 838 " vnc=<display>[,<optargs>]\n" 839 " select display type\n", QEMU_ARCH_ALL) 840STEXI 841@item -display @var{type} 842@findex -display 843Select type of display to use. This option is a replacement for the 844old style -sdl/-curses/... options. Valid values for @var{type} are 845@table @option 846@item sdl 847Display video output via SDL (usually in a separate graphics 848window; see the SDL documentation for other possibilities). 849@item curses 850Display video output via curses. For graphics device models which 851support a text mode, QEMU can display this output using a 852curses/ncurses interface. Nothing is displayed when the graphics 853device is in graphical mode or if the graphics device does not support 854a text mode. Generally only the VGA device models support text mode. 855@item none 856Do not display video output. The guest will still see an emulated 857graphics card, but its output will not be displayed to the QEMU 858user. This option differs from the -nographic option in that it 859only affects what is done with video output; -nographic also changes 860the destination of the serial and parallel port data. 861@item gtk 862Display video output in a GTK window. This interface provides drop-down 863menus and other UI elements to configure and control the VM during 864runtime. 865@item vnc 866Start a VNC server on display <arg> 867@end table 868ETEXI 869 870DEF("nographic", 0, QEMU_OPTION_nographic, 871 "-nographic disable graphical output and redirect serial I/Os to console\n", 872 QEMU_ARCH_ALL) 873STEXI 874@item -nographic 875@findex -nographic 876Normally, QEMU uses SDL to display the VGA output. With this option, 877you can totally disable graphical output so that QEMU is a simple 878command line application. The emulated serial port is redirected on 879the console and muxed with the monitor (unless redirected elsewhere 880explicitly). Therefore, you can still use QEMU to debug a Linux kernel 881with a serial console. Use @key{C-a h} for help on switching between 882the console and monitor. 883ETEXI 884 885DEF("curses", 0, QEMU_OPTION_curses, 886 "-curses use a curses/ncurses interface instead of SDL\n", 887 QEMU_ARCH_ALL) 888STEXI 889@item -curses 890@findex -curses 891Normally, QEMU uses SDL to display the VGA output. With this option, 892QEMU can display the VGA output when in text mode using a 893curses/ncurses interface. Nothing is displayed in graphical mode. 894ETEXI 895 896DEF("no-frame", 0, QEMU_OPTION_no_frame, 897 "-no-frame open SDL window without a frame and window decorations\n", 898 QEMU_ARCH_ALL) 899STEXI 900@item -no-frame 901@findex -no-frame 902Do not use decorations for SDL windows and start them using the whole 903available screen space. This makes the using QEMU in a dedicated desktop 904workspace more convenient. 905ETEXI 906 907DEF("alt-grab", 0, QEMU_OPTION_alt_grab, 908 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n", 909 QEMU_ARCH_ALL) 910STEXI 911@item -alt-grab 912@findex -alt-grab 913Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also 914affects the special keys (for fullscreen, monitor-mode switching, etc). 915ETEXI 916 917DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab, 918 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n", 919 QEMU_ARCH_ALL) 920STEXI 921@item -ctrl-grab 922@findex -ctrl-grab 923Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also 924affects the special keys (for fullscreen, monitor-mode switching, etc). 925ETEXI 926 927DEF("no-quit", 0, QEMU_OPTION_no_quit, 928 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL) 929STEXI 930@item -no-quit 931@findex -no-quit 932Disable SDL window close capability. 933ETEXI 934 935DEF("sdl", 0, QEMU_OPTION_sdl, 936 "-sdl enable SDL\n", QEMU_ARCH_ALL) 937STEXI 938@item -sdl 939@findex -sdl 940Enable SDL. 941ETEXI 942 943DEF("spice", HAS_ARG, QEMU_OPTION_spice, 944 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n" 945 " [,x509-key-file=<file>][,x509-key-password=<file>]\n" 946 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n" 947 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6]\n" 948 " [,tls-ciphers=<list>]\n" 949 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n" 950 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n" 951 " [,sasl][,password=<secret>][,disable-ticketing]\n" 952 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n" 953 " [,jpeg-wan-compression=[auto|never|always]]\n" 954 " [,zlib-glz-wan-compression=[auto|never|always]]\n" 955 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n" 956 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n" 957 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n" 958 " enable spice\n" 959 " at least one of {port, tls-port} is mandatory\n", 960 QEMU_ARCH_ALL) 961STEXI 962@item -spice @var{option}[,@var{option}[,...]] 963@findex -spice 964Enable the spice remote desktop protocol. Valid options are 965 966@table @option 967 968@item port=<nr> 969Set the TCP port spice is listening on for plaintext channels. 970 971@item addr=<addr> 972Set the IP address spice is listening on. Default is any address. 973 974@item ipv4 975@item ipv6 976Force using the specified IP version. 977 978@item password=<secret> 979Set the password you need to authenticate. 980 981@item sasl 982Require that the client use SASL to authenticate with the spice. 983The exact choice of authentication method used is controlled from the 984system / user's SASL configuration file for the 'qemu' service. This 985is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 986unprivileged user, an environment variable SASL_CONF_PATH can be used 987to make it search alternate locations for the service config. 988While some SASL auth methods can also provide data encryption (eg GSSAPI), 989it is recommended that SASL always be combined with the 'tls' and 990'x509' settings to enable use of SSL and server certificates. This 991ensures a data encryption preventing compromise of authentication 992credentials. 993 994@item disable-ticketing 995Allow client connects without authentication. 996 997@item disable-copy-paste 998Disable copy paste between the client and the guest. 999 1000@item disable-agent-file-xfer 1001Disable spice-vdagent based file-xfer between the client and the guest. 1002 1003@item tls-port=<nr> 1004Set the TCP port spice is listening on for encrypted channels. 1005 1006@item x509-dir=<dir> 1007Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir 1008 1009@item x509-key-file=<file> 1010@item x509-key-password=<file> 1011@item x509-cert-file=<file> 1012@item x509-cacert-file=<file> 1013@item x509-dh-key-file=<file> 1014The x509 file names can also be configured individually. 1015 1016@item tls-ciphers=<list> 1017Specify which ciphers to use. 1018 1019@item tls-channel=[main|display|cursor|inputs|record|playback] 1020@item plaintext-channel=[main|display|cursor|inputs|record|playback] 1021Force specific channel to be used with or without TLS encryption. The 1022options can be specified multiple times to configure multiple 1023channels. The special name "default" can be used to set the default 1024mode. For channels which are not explicitly forced into one mode the 1025spice client is allowed to pick tls/plaintext as he pleases. 1026 1027@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off] 1028Configure image compression (lossless). 1029Default is auto_glz. 1030 1031@item jpeg-wan-compression=[auto|never|always] 1032@item zlib-glz-wan-compression=[auto|never|always] 1033Configure wan image compression (lossy for slow links). 1034Default is auto. 1035 1036@item streaming-video=[off|all|filter] 1037Configure video stream detection. Default is filter. 1038 1039@item agent-mouse=[on|off] 1040Enable/disable passing mouse events via vdagent. Default is on. 1041 1042@item playback-compression=[on|off] 1043Enable/disable audio stream compression (using celt 0.5.1). Default is on. 1044 1045@item seamless-migration=[on|off] 1046Enable/disable spice seamless migration. Default is off. 1047 1048@end table 1049ETEXI 1050 1051DEF("portrait", 0, QEMU_OPTION_portrait, 1052 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n", 1053 QEMU_ARCH_ALL) 1054STEXI 1055@item -portrait 1056@findex -portrait 1057Rotate graphical output 90 deg left (only PXA LCD). 1058ETEXI 1059 1060DEF("rotate", HAS_ARG, QEMU_OPTION_rotate, 1061 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n", 1062 QEMU_ARCH_ALL) 1063STEXI 1064@item -rotate @var{deg} 1065@findex -rotate 1066Rotate graphical output some deg left (only PXA LCD). 1067ETEXI 1068 1069DEF("vga", HAS_ARG, QEMU_OPTION_vga, 1070 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|none]\n" 1071 " select video card type\n", QEMU_ARCH_ALL) 1072STEXI 1073@item -vga @var{type} 1074@findex -vga 1075Select type of VGA card to emulate. Valid values for @var{type} are 1076@table @option 1077@item cirrus 1078Cirrus Logic GD5446 Video card. All Windows versions starting from 1079Windows 95 should recognize and use this graphic card. For optimal 1080performances, use 16 bit color depth in the guest and the host OS. 1081(This one is the default) 1082@item std 1083Standard VGA card with Bochs VBE extensions. If your guest OS 1084supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want 1085to use high resolution modes (>= 1280x1024x16) then you should use 1086this option. 1087@item vmware 1088VMWare SVGA-II compatible adapter. Use it if you have sufficiently 1089recent XFree86/XOrg server or Windows guest with a driver for this 1090card. 1091@item qxl 1092QXL paravirtual graphic card. It is VGA compatible (including VESA 10932.0 VBE support). Works best with qxl guest drivers installed though. 1094Recommended choice when using the spice protocol. 1095@item tcx 1096(sun4m only) Sun TCX framebuffer. This is the default framebuffer for 1097sun4m machines and offers both 8-bit and 24-bit colour depths at a 1098fixed resolution of 1024x768. 1099@item cg3 1100(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer 1101for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP) 1102resolutions aimed at people wishing to run older Solaris versions. 1103@item none 1104Disable VGA card. 1105@end table 1106ETEXI 1107 1108DEF("full-screen", 0, QEMU_OPTION_full_screen, 1109 "-full-screen start in full screen\n", QEMU_ARCH_ALL) 1110STEXI 1111@item -full-screen 1112@findex -full-screen 1113Start in full screen. 1114ETEXI 1115 1116DEF("g", 1, QEMU_OPTION_g , 1117 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n", 1118 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 1119STEXI 1120@item -g @var{width}x@var{height}[x@var{depth}] 1121@findex -g 1122Set the initial graphical resolution and depth (PPC, SPARC only). 1123ETEXI 1124 1125DEF("vnc", HAS_ARG, QEMU_OPTION_vnc , 1126 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL) 1127STEXI 1128@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]] 1129@findex -vnc 1130Normally, QEMU uses SDL to display the VGA output. With this option, 1131you can have QEMU listen on VNC display @var{display} and redirect the VGA 1132display over the VNC session. It is very useful to enable the usb 1133tablet device when using this option (option @option{-usbdevice 1134tablet}). When using the VNC display, you must use the @option{-k} 1135parameter to set the keyboard layout if you are not using en-us. Valid 1136syntax for the @var{display} is 1137 1138@table @option 1139 1140@item @var{host}:@var{d} 1141 1142TCP connections will only be allowed from @var{host} on display @var{d}. 1143By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can 1144be omitted in which case the server will accept connections from any host. 1145 1146@item unix:@var{path} 1147 1148Connections will be allowed over UNIX domain sockets where @var{path} is the 1149location of a unix socket to listen for connections on. 1150 1151@item none 1152 1153VNC is initialized but not started. The monitor @code{change} command 1154can be used to later start the VNC server. 1155 1156@end table 1157 1158Following the @var{display} value there may be one or more @var{option} flags 1159separated by commas. Valid options are 1160 1161@table @option 1162 1163@item reverse 1164 1165Connect to a listening VNC client via a ``reverse'' connection. The 1166client is specified by the @var{display}. For reverse network 1167connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument 1168is a TCP port number, not a display number. 1169 1170@item websocket 1171 1172Opens an additional TCP listening port dedicated to VNC Websocket connections. 1173By definition the Websocket port is 5700+@var{display}. If @var{host} is 1174specified connections will only be allowed from this host. 1175As an alternative the Websocket port could be specified by using 1176@code{websocket}=@var{port}. 1177TLS encryption for the Websocket connection is supported if the required 1178certificates are specified with the VNC option @option{x509}. 1179 1180@item password 1181 1182Require that password based authentication is used for client connections. 1183 1184The password must be set separately using the @code{set_password} command in 1185the @ref{pcsys_monitor}. The syntax to change your password is: 1186@code{set_password <protocol> <password>} where <protocol> could be either 1187"vnc" or "spice". 1188 1189If you would like to change <protocol> password expiration, you should use 1190@code{expire_password <protocol> <expiration-time>} where expiration time could 1191be one of the following options: now, never, +seconds or UNIX time of 1192expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800 1193to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this 1194date and time). 1195 1196You can also use keywords "now" or "never" for the expiration time to 1197allow <protocol> password to expire immediately or never expire. 1198 1199@item tls 1200 1201Require that client use TLS when communicating with the VNC server. This 1202uses anonymous TLS credentials so is susceptible to a man-in-the-middle 1203attack. It is recommended that this option be combined with either the 1204@option{x509} or @option{x509verify} options. 1205 1206@item x509=@var{/path/to/certificate/dir} 1207 1208Valid if @option{tls} is specified. Require that x509 credentials are used 1209for negotiating the TLS session. The server will send its x509 certificate 1210to the client. It is recommended that a password be set on the VNC server 1211to provide authentication of the client when this is used. The path following 1212this option specifies where the x509 certificates are to be loaded from. 1213See the @ref{vnc_security} section for details on generating certificates. 1214 1215@item x509verify=@var{/path/to/certificate/dir} 1216 1217Valid if @option{tls} is specified. Require that x509 credentials are used 1218for negotiating the TLS session. The server will send its x509 certificate 1219to the client, and request that the client send its own x509 certificate. 1220The server will validate the client's certificate against the CA certificate, 1221and reject clients when validation fails. If the certificate authority is 1222trusted, this is a sufficient authentication mechanism. You may still wish 1223to set a password on the VNC server as a second authentication layer. The 1224path following this option specifies where the x509 certificates are to 1225be loaded from. See the @ref{vnc_security} section for details on generating 1226certificates. 1227 1228@item sasl 1229 1230Require that the client use SASL to authenticate with the VNC server. 1231The exact choice of authentication method used is controlled from the 1232system / user's SASL configuration file for the 'qemu' service. This 1233is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1234unprivileged user, an environment variable SASL_CONF_PATH can be used 1235to make it search alternate locations for the service config. 1236While some SASL auth methods can also provide data encryption (eg GSSAPI), 1237it is recommended that SASL always be combined with the 'tls' and 1238'x509' settings to enable use of SSL and server certificates. This 1239ensures a data encryption preventing compromise of authentication 1240credentials. See the @ref{vnc_security} section for details on using 1241SASL authentication. 1242 1243@item acl 1244 1245Turn on access control lists for checking of the x509 client certificate 1246and SASL party. For x509 certs, the ACL check is made against the 1247certificate's distinguished name. This is something that looks like 1248@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is 1249made against the username, which depending on the SASL plugin, may 1250include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}. 1251When the @option{acl} flag is set, the initial access list will be 1252empty, with a @code{deny} policy. Thus no one will be allowed to 1253use the VNC server until the ACLs have been loaded. This can be 1254achieved using the @code{acl} monitor command. 1255 1256@item lossy 1257 1258Enable lossy compression methods (gradient, JPEG, ...). If this 1259option is set, VNC client may receive lossy framebuffer updates 1260depending on its encoding settings. Enabling this option can save 1261a lot of bandwidth at the expense of quality. 1262 1263@item non-adaptive 1264 1265Disable adaptive encodings. Adaptive encodings are enabled by default. 1266An adaptive encoding will try to detect frequently updated screen regions, 1267and send updates in these regions using a lossy encoding (like JPEG). 1268This can be really helpful to save bandwidth when playing videos. Disabling 1269adaptive encodings restores the original static behavior of encodings 1270like Tight. 1271 1272@item share=[allow-exclusive|force-shared|ignore] 1273 1274Set display sharing policy. 'allow-exclusive' allows clients to ask 1275for exclusive access. As suggested by the rfb spec this is 1276implemented by dropping other connections. Connecting multiple 1277clients in parallel requires all clients asking for a shared session 1278(vncviewer: -shared switch). This is the default. 'force-shared' 1279disables exclusive client access. Useful for shared desktop sessions, 1280where you don't want someone forgetting specify -shared disconnect 1281everybody else. 'ignore' completely ignores the shared flag and 1282allows everybody connect unconditionally. Doesn't conform to the rfb 1283spec but is traditional QEMU behavior. 1284 1285@end table 1286ETEXI 1287 1288STEXI 1289@end table 1290ETEXI 1291ARCHHEADING(, QEMU_ARCH_I386) 1292 1293ARCHHEADING(i386 target only:, QEMU_ARCH_I386) 1294STEXI 1295@table @option 1296ETEXI 1297 1298DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack, 1299 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n", 1300 QEMU_ARCH_I386) 1301STEXI 1302@item -win2k-hack 1303@findex -win2k-hack 1304Use it when installing Windows 2000 to avoid a disk full bug. After 1305Windows 2000 is installed, you no longer need this option (this option 1306slows down the IDE transfers). 1307ETEXI 1308 1309HXCOMM Deprecated by -rtc 1310DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386) 1311 1312DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk, 1313 "-no-fd-bootchk disable boot signature checking for floppy disks\n", 1314 QEMU_ARCH_I386) 1315STEXI 1316@item -no-fd-bootchk 1317@findex -no-fd-bootchk 1318Disable boot signature checking for floppy disks in BIOS. May 1319be needed to boot from old floppy disks. 1320ETEXI 1321 1322DEF("no-acpi", 0, QEMU_OPTION_no_acpi, 1323 "-no-acpi disable ACPI\n", QEMU_ARCH_I386) 1324STEXI 1325@item -no-acpi 1326@findex -no-acpi 1327Disable ACPI (Advanced Configuration and Power Interface) support. Use 1328it if your guest OS complains about ACPI problems (PC target machine 1329only). 1330ETEXI 1331 1332DEF("no-hpet", 0, QEMU_OPTION_no_hpet, 1333 "-no-hpet disable HPET\n", QEMU_ARCH_I386) 1334STEXI 1335@item -no-hpet 1336@findex -no-hpet 1337Disable HPET support. 1338ETEXI 1339 1340DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable, 1341 "-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" 1342 " ACPI table description\n", QEMU_ARCH_I386) 1343STEXI 1344@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}]...] 1345@findex -acpitable 1346Add ACPI table with specified header fields and context from specified files. 1347For file=, take whole ACPI table from the specified files, including all 1348ACPI headers (possible overridden by other options). 1349For data=, only data 1350portion of the table is used, all header information is specified in the 1351command line. 1352ETEXI 1353 1354DEF("smbios", HAS_ARG, QEMU_OPTION_smbios, 1355 "-smbios file=binary\n" 1356 " load SMBIOS entry from binary file\n" 1357 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d][,uefi=on|off]\n" 1358 " specify SMBIOS type 0 fields\n" 1359 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1360 " [,uuid=uuid][,sku=str][,family=str]\n" 1361 " specify SMBIOS type 1 fields\n", QEMU_ARCH_I386) 1362STEXI 1363@item -smbios file=@var{binary} 1364@findex -smbios 1365Load SMBIOS entry from binary file. 1366 1367@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off] 1368Specify SMBIOS type 0 fields 1369 1370@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}] 1371Specify SMBIOS type 1 fields 1372ETEXI 1373 1374STEXI 1375@end table 1376ETEXI 1377DEFHEADING() 1378 1379DEFHEADING(Network options:) 1380STEXI 1381@table @option 1382ETEXI 1383 1384HXCOMM Legacy slirp options (now moved to -net user): 1385#ifdef CONFIG_SLIRP 1386DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL) 1387DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL) 1388DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL) 1389#ifndef _WIN32 1390DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL) 1391#endif 1392#endif 1393 1394DEF("net", HAS_ARG, QEMU_OPTION_net, 1395 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n" 1396 " create a new Network Interface Card and connect it to VLAN 'n'\n" 1397#ifdef CONFIG_SLIRP 1398 "-net user[,vlan=n][,name=str][,net=addr[/mask]][,host=addr][,restrict=on|off]\n" 1399 " [,hostname=host][,dhcpstart=addr][,dns=addr][,dnssearch=domain][,tftp=dir]\n" 1400 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]" 1401#ifndef _WIN32 1402 "[,smb=dir[,smbserver=addr]]\n" 1403#endif 1404 " connect the user mode network stack to VLAN 'n', configure its\n" 1405 " DHCP server and enabled optional services\n" 1406#endif 1407#ifdef _WIN32 1408 "-net tap[,vlan=n][,name=str],ifname=name\n" 1409 " connect the host TAP network interface to VLAN 'n'\n" 1410#else 1411 "-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" 1412 " connect the host TAP network interface to VLAN 'n'\n" 1413 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n" 1414 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n" 1415 " to deconfigure it\n" 1416 " use '[down]script=no' to disable script execution\n" 1417 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n" 1418 " configure it\n" 1419 " use 'fd=h' to connect to an already opened TAP interface\n" 1420 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n" 1421 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n" 1422 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n" 1423 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n" 1424 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" 1425 " use vhost=on to enable experimental in kernel accelerator\n" 1426 " (only has effect for virtio guests which use MSIX)\n" 1427 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n" 1428 " use 'vhostfd=h' to connect to an already opened vhost net device\n" 1429 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n" 1430 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n" 1431 "-net bridge[,vlan=n][,name=str][,br=bridge][,helper=helper]\n" 1432 " connects a host TAP network interface to a host bridge device 'br'\n" 1433 " (default=" DEFAULT_BRIDGE_INTERFACE ") using the program 'helper'\n" 1434 " (default=" DEFAULT_BRIDGE_HELPER ")\n" 1435#endif 1436 "-net socket[,vlan=n][,name=str][,fd=h][,listen=[host]:port][,connect=host:port]\n" 1437 " connect the vlan 'n' to another VLAN using a socket connection\n" 1438 "-net socket[,vlan=n][,name=str][,fd=h][,mcast=maddr:port[,localaddr=addr]]\n" 1439 " connect the vlan 'n' to multicast maddr and port\n" 1440 " use 'localaddr=addr' to specify the host address to send packets from\n" 1441 "-net socket[,vlan=n][,name=str][,fd=h][,udp=host:port][,localaddr=host:port]\n" 1442 " connect the vlan 'n' to another VLAN using an UDP tunnel\n" 1443#ifdef CONFIG_VDE 1444 "-net vde[,vlan=n][,name=str][,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n" 1445 " connect the vlan 'n' to port 'n' of a vde switch running\n" 1446 " on host and listening for incoming connections on 'socketpath'.\n" 1447 " Use group 'groupname' and mode 'octalmode' to change default\n" 1448 " ownership and permissions for communication port.\n" 1449#endif 1450#ifdef CONFIG_NETMAP 1451 "-net netmap,ifname=name[,devname=nmname]\n" 1452 " attach to the existing netmap-enabled network interface 'name', or to a\n" 1453 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n" 1454 " netmap device, defaults to '/dev/netmap')\n" 1455#endif 1456 "-net dump[,vlan=n][,file=f][,len=n]\n" 1457 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n" 1458 "-net none use it alone to have zero network devices. If no -net option\n" 1459 " is provided, the default is '-net nic -net user'\n", QEMU_ARCH_ALL) 1460DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, 1461 "-netdev [" 1462#ifdef CONFIG_SLIRP 1463 "user|" 1464#endif 1465 "tap|" 1466 "bridge|" 1467#ifdef CONFIG_VDE 1468 "vde|" 1469#endif 1470#ifdef CONFIG_NETMAP 1471 "netmap|" 1472#endif 1473 "vhost-user|" 1474 "socket|" 1475 "hubport],id=str[,option][,option][,...]\n", QEMU_ARCH_ALL) 1476STEXI 1477@item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}] 1478@findex -net 1479Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n} 1480= 0 is the default). The NIC is an e1000 by default on the PC 1481target. Optionally, the MAC address can be changed to @var{mac}, the 1482device address set to @var{addr} (PCI cards only), 1483and a @var{name} can be assigned for use in monitor commands. 1484Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors 1485that the card should have; this option currently only affects virtio cards; set 1486@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single 1487NIC is created. QEMU can emulate several different models of network card. 1488Valid values for @var{type} are 1489@code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er}, 1490@code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139}, 1491@code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}. 1492Not all devices are supported on all targets. Use @code{-net nic,model=help} 1493for a list of available devices for your target. 1494 1495@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...] 1496@findex -netdev 1497@item -net user[,@var{option}][,@var{option}][,...] 1498Use the user mode network stack which requires no administrator 1499privilege to run. Valid options are: 1500 1501@table @option 1502@item vlan=@var{n} 1503Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default). 1504 1505@item id=@var{id} 1506@item name=@var{name} 1507Assign symbolic name for use in monitor commands. 1508 1509@item net=@var{addr}[/@var{mask}] 1510Set IP network address the guest will see. Optionally specify the netmask, 1511either in the form a.b.c.d or as number of valid top-most bits. Default is 151210.0.2.0/24. 1513 1514@item host=@var{addr} 1515Specify the guest-visible address of the host. Default is the 2nd IP in the 1516guest network, i.e. x.x.x.2. 1517 1518@item restrict=on|off 1519If this option is enabled, the guest will be isolated, i.e. it will not be 1520able to contact the host and no guest IP packets will be routed over the host 1521to the outside. This option does not affect any explicitly set forwarding rules. 1522 1523@item hostname=@var{name} 1524Specifies the client hostname reported by the built-in DHCP server. 1525 1526@item dhcpstart=@var{addr} 1527Specify the first of the 16 IPs the built-in DHCP server can assign. Default 1528is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31. 1529 1530@item dns=@var{addr} 1531Specify the guest-visible address of the virtual nameserver. The address must 1532be different from the host address. Default is the 3rd IP in the guest network, 1533i.e. x.x.x.3. 1534 1535@item dnssearch=@var{domain} 1536Provides an entry for the domain-search list sent by the built-in 1537DHCP server. More than one domain suffix can be transmitted by specifying 1538this option multiple times. If supported, this will cause the guest to 1539automatically try to append the given domain suffix(es) in case a domain name 1540can not be resolved. 1541 1542Example: 1543@example 1544qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...] 1545@end example 1546 1547@item tftp=@var{dir} 1548When using the user mode network stack, activate a built-in TFTP 1549server. The files in @var{dir} will be exposed as the root of a TFTP server. 1550The TFTP client on the guest must be configured in binary mode (use the command 1551@code{bin} of the Unix TFTP client). 1552 1553@item bootfile=@var{file} 1554When using the user mode network stack, broadcast @var{file} as the BOOTP 1555filename. In conjunction with @option{tftp}, this can be used to network boot 1556a guest from a local directory. 1557 1558Example (using pxelinux): 1559@example 1560qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0 1561@end example 1562 1563@item smb=@var{dir}[,smbserver=@var{addr}] 1564When using the user mode network stack, activate a built-in SMB 1565server so that Windows OSes can access to the host files in @file{@var{dir}} 1566transparently. The IP address of the SMB server can be set to @var{addr}. By 1567default the 4th IP in the guest network is used, i.e. x.x.x.4. 1568 1569In the guest Windows OS, the line: 1570@example 157110.0.2.4 smbserver 1572@end example 1573must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me) 1574or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000). 1575 1576Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}. 1577 1578Note that a SAMBA server must be installed on the host OS. 1579QEMU was tested successfully with smbd versions from Red Hat 9, 1580Fedora Core 3 and OpenSUSE 11.x. 1581 1582@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport} 1583Redirect incoming TCP or UDP connections to the host port @var{hostport} to 1584the guest IP address @var{guestaddr} on guest port @var{guestport}. If 1585@var{guestaddr} is not specified, its value is x.x.x.15 (default first address 1586given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can 1587be bound to a specific host interface. If no connection type is set, TCP is 1588used. This option can be given multiple times. 1589 1590For example, to redirect host X11 connection from screen 1 to guest 1591screen 0, use the following: 1592 1593@example 1594# on the host 1595qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...] 1596# this host xterm should open in the guest X11 server 1597xterm -display :1 1598@end example 1599 1600To redirect telnet connections from host port 5555 to telnet port on 1601the guest, use the following: 1602 1603@example 1604# on the host 1605qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...] 1606telnet localhost 5555 1607@end example 1608 1609Then when you use on the host @code{telnet localhost 5555}, you 1610connect to the guest telnet server. 1611 1612@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev} 1613@item guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command} 1614Forward guest TCP connections to the IP address @var{server} on port @var{port} 1615to the character device @var{dev} or to a program executed by @var{cmd:command} 1616which gets spawned for each connection. This option can be given multiple times. 1617 1618You can either use a chardev directly and have that one used throughout QEMU's 1619lifetime, like in the following example: 1620 1621@example 1622# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever 1623# the guest accesses it 1624qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...] 1625@end example 1626 1627Or you can execute a command on every TCP connection established by the guest, 1628so that QEMU behaves similar to an inetd process for that virtual server: 1629 1630@example 1631# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 1632# and connect the TCP stream to its stdin/stdout 1633qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321' 1634@end example 1635 1636@end table 1637 1638Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still 1639processed and applied to -net user. Mixing them with the new configuration 1640syntax gives undefined results. Their use for new applications is discouraged 1641as they will be removed from future versions. 1642 1643@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}] 1644@item -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}] 1645Connect the host TAP network interface @var{name} to VLAN @var{n}. 1646 1647Use the network script @var{file} to configure it and the network script 1648@var{dfile} to deconfigure it. If @var{name} is not provided, the OS 1649automatically provides one. The default network configure script is 1650@file{/etc/qemu-ifup} and the default network deconfigure script is 1651@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no} 1652to disable script execution. 1653 1654If running QEMU as an unprivileged user, use the network helper 1655@var{helper} to configure the TAP interface. The default network 1656helper executable is @file{/path/to/qemu-bridge-helper}. 1657 1658@option{fd}=@var{h} can be used to specify the handle of an already 1659opened host TAP interface. 1660 1661Examples: 1662 1663@example 1664#launch a QEMU instance with the default network script 1665qemu-system-i386 linux.img -net nic -net tap 1666@end example 1667 1668@example 1669#launch a QEMU instance with two NICs, each one connected 1670#to a TAP device 1671qemu-system-i386 linux.img \ 1672 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \ 1673 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1 1674@end example 1675 1676@example 1677#launch a QEMU instance with the default network helper to 1678#connect a TAP device to bridge br0 1679qemu-system-i386 linux.img \ 1680 -net nic -net tap,"helper=/path/to/qemu-bridge-helper" 1681@end example 1682 1683@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}] 1684@item -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}] 1685Connect a host TAP network interface to a host bridge device. 1686 1687Use the network helper @var{helper} to configure the TAP interface and 1688attach it to the bridge. The default network helper executable is 1689@file{/path/to/qemu-bridge-helper} and the default bridge 1690device is @file{br0}. 1691 1692Examples: 1693 1694@example 1695#launch a QEMU instance with the default network helper to 1696#connect a TAP device to bridge br0 1697qemu-system-i386 linux.img -net bridge -net nic,model=virtio 1698@end example 1699 1700@example 1701#launch a QEMU instance with the default network helper to 1702#connect a TAP device to bridge qemubr0 1703qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio 1704@end example 1705 1706@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 1707@item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 1708 1709Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual 1710machine using a TCP socket connection. If @option{listen} is 1711specified, QEMU waits for incoming connections on @var{port} 1712(@var{host} is optional). @option{connect} is used to connect to 1713another QEMU instance using the @option{listen} option. @option{fd}=@var{h} 1714specifies an already opened TCP socket. 1715 1716Example: 1717@example 1718# launch a first QEMU instance 1719qemu-system-i386 linux.img \ 1720 -net nic,macaddr=52:54:00:12:34:56 \ 1721 -net socket,listen=:1234 1722# connect the VLAN 0 of this instance to the VLAN 0 1723# of the first instance 1724qemu-system-i386 linux.img \ 1725 -net nic,macaddr=52:54:00:12:34:57 \ 1726 -net socket,connect=127.0.0.1:1234 1727@end example 1728 1729@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 1730@item -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 1731 1732Create a VLAN @var{n} shared with another QEMU virtual 1733machines using a UDP multicast socket, effectively making a bus for 1734every QEMU with same multicast address @var{maddr} and @var{port}. 1735NOTES: 1736@enumerate 1737@item 1738Several QEMU can be running on different hosts and share same bus (assuming 1739correct multicast setup for these hosts). 1740@item 1741mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see 1742@url{http://user-mode-linux.sf.net}. 1743@item 1744Use @option{fd=h} to specify an already opened UDP multicast socket. 1745@end enumerate 1746 1747Example: 1748@example 1749# launch one QEMU instance 1750qemu-system-i386 linux.img \ 1751 -net nic,macaddr=52:54:00:12:34:56 \ 1752 -net socket,mcast=230.0.0.1:1234 1753# launch another QEMU instance on same "bus" 1754qemu-system-i386 linux.img \ 1755 -net nic,macaddr=52:54:00:12:34:57 \ 1756 -net socket,mcast=230.0.0.1:1234 1757# launch yet another QEMU instance on same "bus" 1758qemu-system-i386 linux.img \ 1759 -net nic,macaddr=52:54:00:12:34:58 \ 1760 -net socket,mcast=230.0.0.1:1234 1761@end example 1762 1763Example (User Mode Linux compat.): 1764@example 1765# launch QEMU instance (note mcast address selected 1766# is UML's default) 1767qemu-system-i386 linux.img \ 1768 -net nic,macaddr=52:54:00:12:34:56 \ 1769 -net socket,mcast=239.192.168.1:1102 1770# launch UML 1771/path/to/linux ubd0=/path/to/root_fs eth0=mcast 1772@end example 1773 1774Example (send packets from host's 1.2.3.4): 1775@example 1776qemu-system-i386 linux.img \ 1777 -net nic,macaddr=52:54:00:12:34:56 \ 1778 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4 1779@end example 1780 1781@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 1782@item -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 1783Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and 1784listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname} 1785and MODE @var{octalmode} to change default ownership and permissions for 1786communication port. This option is only available if QEMU has been compiled 1787with vde support enabled. 1788 1789Example: 1790@example 1791# launch vde switch 1792vde_switch -F -sock /tmp/myswitch 1793# launch QEMU instance 1794qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch 1795@end example 1796 1797@item -netdev hubport,id=@var{id},hubid=@var{hubid} 1798 1799Create a hub port on QEMU "vlan" @var{hubid}. 1800 1801The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single 1802netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the 1803required hub automatically. 1804 1805@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off] 1806 1807Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should 1808be a unix domain socket backed one. The vhost-user uses a specifically defined 1809protocol to pass vhost ioctl replacement messages to an application on the other 1810end of the socket. On non-MSIX guests, the feature can be forced with 1811@var{vhostforce}. 1812 1813Example: 1814@example 1815qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \ 1816 -numa node,memdev=mem \ 1817 -chardev socket,path=/path/to/socket \ 1818 -netdev type=vhost-user,id=net0,chardev=chr0 \ 1819 -device virtio-net-pci,netdev=net0 1820@end example 1821 1822@item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}] 1823Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default). 1824At most @var{len} bytes (64k by default) per packet are stored. The file format is 1825libpcap, so it can be analyzed with tools such as tcpdump or Wireshark. 1826 1827@item -net none 1828Indicate that no network devices should be configured. It is used to 1829override the default configuration (@option{-net nic -net user}) which 1830is activated if no @option{-net} options are provided. 1831ETEXI 1832 1833STEXI 1834@end table 1835ETEXI 1836DEFHEADING() 1837 1838DEFHEADING(Character device options:) 1839STEXI 1840 1841The general form of a character device option is: 1842@table @option 1843ETEXI 1844 1845DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, 1846 "-chardev null,id=id[,mux=on|off]\n" 1847 "-chardev socket,id=id[,host=host],port=host[,to=to][,ipv4][,ipv6][,nodelay]\n" 1848 " [,server][,nowait][,telnet][,mux=on|off] (tcp)\n" 1849 "-chardev socket,id=id,path=path[,server][,nowait][,telnet],[mux=on|off] (unix)\n" 1850 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" 1851 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n" 1852 "-chardev msmouse,id=id[,mux=on|off]\n" 1853 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n" 1854 " [,mux=on|off]\n" 1855 "-chardev ringbuf,id=id[,size=size]\n" 1856 "-chardev file,id=id,path=path[,mux=on|off]\n" 1857 "-chardev pipe,id=id,path=path[,mux=on|off]\n" 1858#ifdef _WIN32 1859 "-chardev console,id=id[,mux=on|off]\n" 1860 "-chardev serial,id=id,path=path[,mux=on|off]\n" 1861#else 1862 "-chardev pty,id=id[,mux=on|off]\n" 1863 "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n" 1864#endif 1865#ifdef CONFIG_BRLAPI 1866 "-chardev braille,id=id[,mux=on|off]\n" 1867#endif 1868#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 1869 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) 1870 "-chardev serial,id=id,path=path[,mux=on|off]\n" 1871 "-chardev tty,id=id,path=path[,mux=on|off]\n" 1872#endif 1873#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) 1874 "-chardev parallel,id=id,path=path[,mux=on|off]\n" 1875 "-chardev parport,id=id,path=path[,mux=on|off]\n" 1876#endif 1877#if defined(CONFIG_SPICE) 1878 "-chardev spicevmc,id=id,name=name[,debug=debug]\n" 1879 "-chardev spiceport,id=id,name=name[,debug=debug]\n" 1880#endif 1881 , QEMU_ARCH_ALL 1882) 1883 1884STEXI 1885@item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}] 1886@findex -chardev 1887Backend is one of: 1888@option{null}, 1889@option{socket}, 1890@option{udp}, 1891@option{msmouse}, 1892@option{vc}, 1893@option{ringbuf}, 1894@option{file}, 1895@option{pipe}, 1896@option{console}, 1897@option{serial}, 1898@option{pty}, 1899@option{stdio}, 1900@option{braille}, 1901@option{tty}, 1902@option{parallel}, 1903@option{parport}, 1904@option{spicevmc}. 1905@option{spiceport}. 1906The specific backend will determine the applicable options. 1907 1908All devices must have an id, which can be any string up to 127 characters long. 1909It is used to uniquely identify this device in other command line directives. 1910 1911A character device may be used in multiplexing mode by multiple front-ends. 1912The key sequence of @key{Control-a} and @key{c} will rotate the input focus 1913between attached front-ends. Specify @option{mux=on} to enable this mode. 1914 1915Options to each backend are described below. 1916 1917@item -chardev null ,id=@var{id} 1918A void device. This device will not emit any data, and will drop any data it 1919receives. The null backend does not take any options. 1920 1921@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] 1922 1923Create a two-way stream socket, which can be either a TCP or a unix socket. A 1924unix socket will be created if @option{path} is specified. Behaviour is 1925undefined if TCP options are specified for a unix socket. 1926 1927@option{server} specifies that the socket shall be a listening socket. 1928 1929@option{nowait} specifies that QEMU should not block waiting for a client to 1930connect to a listening socket. 1931 1932@option{telnet} specifies that traffic on the socket should interpret telnet 1933escape sequences. 1934 1935TCP and unix socket options are given below: 1936 1937@table @option 1938 1939@item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay] 1940 1941@option{host} for a listening socket specifies the local address to be bound. 1942For a connecting socket species the remote host to connect to. @option{host} is 1943optional for listening sockets. If not specified it defaults to @code{0.0.0.0}. 1944 1945@option{port} for a listening socket specifies the local port to be bound. For a 1946connecting socket specifies the port on the remote host to connect to. 1947@option{port} can be given as either a port number or a service name. 1948@option{port} is required. 1949 1950@option{to} is only relevant to listening sockets. If it is specified, and 1951@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up 1952to and including @option{to} until it succeeds. @option{to} must be specified 1953as a port number. 1954 1955@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 1956If neither is specified the socket may use either protocol. 1957 1958@option{nodelay} disables the Nagle algorithm. 1959 1960@item unix options: path=@var{path} 1961 1962@option{path} specifies the local path of the unix socket. @option{path} is 1963required. 1964 1965@end table 1966 1967@item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6] 1968 1969Sends all traffic from the guest to a remote host over UDP. 1970 1971@option{host} specifies the remote host to connect to. If not specified it 1972defaults to @code{localhost}. 1973 1974@option{port} specifies the port on the remote host to connect to. @option{port} 1975is required. 1976 1977@option{localaddr} specifies the local address to bind to. If not specified it 1978defaults to @code{0.0.0.0}. 1979 1980@option{localport} specifies the local port to bind to. If not specified any 1981available local port will be used. 1982 1983@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 1984If neither is specified the device may use either protocol. 1985 1986@item -chardev msmouse ,id=@var{id} 1987 1988Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not 1989take any options. 1990 1991@item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]] 1992 1993Connect to a QEMU text console. @option{vc} may optionally be given a specific 1994size. 1995 1996@option{width} and @option{height} specify the width and height respectively of 1997the console, in pixels. 1998 1999@option{cols} and @option{rows} specify that the console be sized to fit a text 2000console with the given dimensions. 2001 2002@item -chardev ringbuf ,id=@var{id} [,size=@var{size}] 2003 2004Create a ring buffer with fixed size @option{size}. 2005@var{size} must be a power of two, and defaults to @code{64K}). 2006 2007@item -chardev file ,id=@var{id} ,path=@var{path} 2008 2009Log all traffic received from the guest to a file. 2010 2011@option{path} specifies the path of the file to be opened. This file will be 2012created if it does not already exist, and overwritten if it does. @option{path} 2013is required. 2014 2015@item -chardev pipe ,id=@var{id} ,path=@var{path} 2016 2017Create a two-way connection to the guest. The behaviour differs slightly between 2018Windows hosts and other hosts: 2019 2020On Windows, a single duplex pipe will be created at 2021@file{\\.pipe\@option{path}}. 2022 2023On other hosts, 2 pipes will be created called @file{@option{path}.in} and 2024@file{@option{path}.out}. Data written to @file{@option{path}.in} will be 2025received by the guest. Data written by the guest can be read from 2026@file{@option{path}.out}. QEMU will not create these fifos, and requires them to 2027be present. 2028 2029@option{path} forms part of the pipe path as described above. @option{path} is 2030required. 2031 2032@item -chardev console ,id=@var{id} 2033 2034Send traffic from the guest to QEMU's standard output. @option{console} does not 2035take any options. 2036 2037@option{console} is only available on Windows hosts. 2038 2039@item -chardev serial ,id=@var{id} ,path=@option{path} 2040 2041Send traffic from the guest to a serial device on the host. 2042 2043On Unix hosts serial will actually accept any tty device, 2044not only serial lines. 2045 2046@option{path} specifies the name of the serial device to open. 2047 2048@item -chardev pty ,id=@var{id} 2049 2050Create a new pseudo-terminal on the host and connect to it. @option{pty} does 2051not take any options. 2052 2053@option{pty} is not available on Windows hosts. 2054 2055@item -chardev stdio ,id=@var{id} [,signal=on|off] 2056Connect to standard input and standard output of the QEMU process. 2057 2058@option{signal} controls if signals are enabled on the terminal, that includes 2059exiting QEMU with the key sequence @key{Control-c}. This option is enabled by 2060default, use @option{signal=off} to disable it. 2061 2062@option{stdio} is not available on Windows hosts. 2063 2064@item -chardev braille ,id=@var{id} 2065 2066Connect to a local BrlAPI server. @option{braille} does not take any options. 2067 2068@item -chardev tty ,id=@var{id} ,path=@var{path} 2069 2070@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and 2071DragonFlyBSD hosts. It is an alias for @option{serial}. 2072 2073@option{path} specifies the path to the tty. @option{path} is required. 2074 2075@item -chardev parallel ,id=@var{id} ,path=@var{path} 2076@item -chardev parport ,id=@var{id} ,path=@var{path} 2077 2078@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts. 2079 2080Connect to a local parallel port. 2081 2082@option{path} specifies the path to the parallel port device. @option{path} is 2083required. 2084 2085@item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name} 2086 2087@option{spicevmc} is only available when spice support is built in. 2088 2089@option{debug} debug level for spicevmc 2090 2091@option{name} name of spice channel to connect to 2092 2093Connect to a spice virtual machine channel, such as vdiport. 2094 2095@item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name} 2096 2097@option{spiceport} is only available when spice support is built in. 2098 2099@option{debug} debug level for spicevmc 2100 2101@option{name} name of spice port to connect to 2102 2103Connect to a spice port, allowing a Spice client to handle the traffic 2104identified by a name (preferably a fqdn). 2105ETEXI 2106 2107STEXI 2108@end table 2109ETEXI 2110DEFHEADING() 2111 2112DEFHEADING(Device URL Syntax:) 2113STEXI 2114 2115In addition to using normal file images for the emulated storage devices, 2116QEMU can also use networked resources such as iSCSI devices. These are 2117specified using a special URL syntax. 2118 2119@table @option 2120@item iSCSI 2121iSCSI support allows QEMU to access iSCSI resources directly and use as 2122images for the guest storage. Both disk and cdrom images are supported. 2123 2124Syntax for specifying iSCSI LUNs is 2125``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>'' 2126 2127By default qemu will use the iSCSI initiator-name 2128'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command 2129line or a configuration file. 2130 2131 2132Example (without authentication): 2133@example 2134qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \ 2135 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \ 2136 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 2137@end example 2138 2139Example (CHAP username/password via URL): 2140@example 2141qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1 2142@end example 2143 2144Example (CHAP username/password via environment variables): 2145@example 2146LIBISCSI_CHAP_USERNAME="user" \ 2147LIBISCSI_CHAP_PASSWORD="password" \ 2148qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 2149@end example 2150 2151iSCSI support is an optional feature of QEMU and only available when 2152compiled and linked against libiscsi. 2153ETEXI 2154DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi, 2155 "-iscsi [user=user][,password=password]\n" 2156 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n" 2157 " [,initiator-name=initiator-iqn][,id=target-iqn]\n" 2158 " iSCSI session parameters\n", QEMU_ARCH_ALL) 2159STEXI 2160 2161iSCSI parameters such as username and password can also be specified via 2162a configuration file. See qemu-doc for more information and examples. 2163 2164@item NBD 2165QEMU supports NBD (Network Block Devices) both using TCP protocol as well 2166as Unix Domain Sockets. 2167 2168Syntax for specifying a NBD device using TCP 2169``nbd:<server-ip>:<port>[:exportname=<export>]'' 2170 2171Syntax for specifying a NBD device using Unix Domain Sockets 2172``nbd:unix:<domain-socket>[:exportname=<export>]'' 2173 2174 2175Example for TCP 2176@example 2177qemu-system-i386 --drive file=nbd:192.0.2.1:30000 2178@end example 2179 2180Example for Unix Domain Sockets 2181@example 2182qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket 2183@end example 2184 2185@item SSH 2186QEMU supports SSH (Secure Shell) access to remote disks. 2187 2188Examples: 2189@example 2190qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img 2191qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img 2192@end example 2193 2194Currently authentication must be done using ssh-agent. Other 2195authentication methods may be supported in future. 2196 2197@item Sheepdog 2198Sheepdog is a distributed storage system for QEMU. 2199QEMU supports using either local sheepdog devices or remote networked 2200devices. 2201 2202Syntax for specifying a sheepdog device 2203@example 2204sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag] 2205@end example 2206 2207Example 2208@example 2209qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine 2210@end example 2211 2212See also @url{http://http://www.osrg.net/sheepdog/}. 2213 2214@item GlusterFS 2215GlusterFS is an user space distributed file system. 2216QEMU supports the use of GlusterFS volumes for hosting VM disk images using 2217TCP, Unix Domain Sockets and RDMA transport protocols. 2218 2219Syntax for specifying a VM disk image on GlusterFS volume is 2220@example 2221gluster[+transport]://[server[:port]]/volname/image[?socket=...] 2222@end example 2223 2224 2225Example 2226@example 2227qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img 2228@end example 2229 2230See also @url{http://www.gluster.org}. 2231 2232@item HTTP/HTTPS/FTP/FTPS/TFTP 2233QEMU supports read-only access to files accessed over http(s), ftp(s) and tftp. 2234 2235Syntax using a single filename: 2236@example 2237<protocol>://[<username>[:<password>]@@]<host>/<path> 2238@end example 2239 2240where: 2241@table @option 2242@item protocol 2243'http', 'https', 'ftp', 'ftps', or 'tftp'. 2244 2245@item username 2246Optional username for authentication to the remote server. 2247 2248@item password 2249Optional password for authentication to the remote server. 2250 2251@item host 2252Address of the remote server. 2253 2254@item path 2255Path on the remote server, including any query string. 2256@end table 2257 2258The following options are also supported: 2259@table @option 2260@item url 2261The full URL when passing options to the driver explicitly. 2262 2263@item readahead 2264The amount of data to read ahead with each range request to the remote server. 2265This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it 2266does not have a suffix, it will be assumed to be in bytes. The value must be a 2267multiple of 512 bytes. It defaults to 256k. 2268 2269@item sslverify 2270Whether to verify the remote server's certificate when connecting over SSL. It 2271can have the value 'on' or 'off'. It defaults to 'on'. 2272@end table 2273 2274Note that when passing options to qemu explicitly, @option{driver} is the value 2275of <protocol>. 2276 2277Example: boot from a remote Fedora 20 live ISO image 2278@example 2279qemu-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 2280 2281qemu-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 2282@end example 2283 2284Example: boot from a remote Fedora 20 cloud image using a local overlay for 2285writes, copy-on-read, and a readahead of 64k 2286@example 2287qemu-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 2288 2289qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on 2290@end example 2291 2292Example: boot from an image stored on a VMware vSphere server with a self-signed 2293certificate using a local overlay for writes and a readahead of 64k 2294@example 2295qemu-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"@}' /tmp/test.qcow2 2296 2297qemu-system-x86_64 -drive file=/tmp/test.qcow2 2298@end example 2299ETEXI 2300 2301STEXI 2302@end table 2303ETEXI 2304 2305DEFHEADING(Bluetooth(R) options:) 2306STEXI 2307@table @option 2308ETEXI 2309 2310DEF("bt", HAS_ARG, QEMU_OPTION_bt, \ 2311 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \ 2312 "-bt hci,host[:id]\n" \ 2313 " use host's HCI with the given name\n" \ 2314 "-bt hci[,vlan=n]\n" \ 2315 " emulate a standard HCI in virtual scatternet 'n'\n" \ 2316 "-bt vhci[,vlan=n]\n" \ 2317 " add host computer to virtual scatternet 'n' using VHCI\n" \ 2318 "-bt device:dev[,vlan=n]\n" \ 2319 " emulate a bluetooth device 'dev' in scatternet 'n'\n", 2320 QEMU_ARCH_ALL) 2321STEXI 2322@item -bt hci[...] 2323@findex -bt 2324Defines the function of the corresponding Bluetooth HCI. -bt options 2325are matched with the HCIs present in the chosen machine type. For 2326example when emulating a machine with only one HCI built into it, only 2327the first @code{-bt hci[...]} option is valid and defines the HCI's 2328logic. The Transport Layer is decided by the machine type. Currently 2329the machines @code{n800} and @code{n810} have one HCI and all other 2330machines have none. 2331 2332@anchor{bt-hcis} 2333The following three types are recognized: 2334 2335@table @option 2336@item -bt hci,null 2337(default) The corresponding Bluetooth HCI assumes no internal logic 2338and will not respond to any HCI commands or emit events. 2339 2340@item -bt hci,host[:@var{id}] 2341(@code{bluez} only) The corresponding HCI passes commands / events 2342to / from the physical HCI identified by the name @var{id} (default: 2343@code{hci0}) on the computer running QEMU. Only available on @code{bluez} 2344capable systems like Linux. 2345 2346@item -bt hci[,vlan=@var{n}] 2347Add a virtual, standard HCI that will participate in the Bluetooth 2348scatternet @var{n} (default @code{0}). Similarly to @option{-net} 2349VLANs, devices inside a bluetooth network @var{n} can only communicate 2350with other devices in the same network (scatternet). 2351@end table 2352 2353@item -bt vhci[,vlan=@var{n}] 2354(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached 2355to the host bluetooth stack instead of to the emulated target. This 2356allows the host and target machines to participate in a common scatternet 2357and communicate. Requires the Linux @code{vhci} driver installed. Can 2358be used as following: 2359 2360@example 2361qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5 2362@end example 2363 2364@item -bt device:@var{dev}[,vlan=@var{n}] 2365Emulate a bluetooth device @var{dev} and place it in network @var{n} 2366(default @code{0}). QEMU can only emulate one type of bluetooth devices 2367currently: 2368 2369@table @option 2370@item keyboard 2371Virtual wireless keyboard implementing the HIDP bluetooth profile. 2372@end table 2373ETEXI 2374 2375STEXI 2376@end table 2377ETEXI 2378DEFHEADING() 2379 2380#ifdef CONFIG_TPM 2381DEFHEADING(TPM device options:) 2382 2383DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \ 2384 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n" 2385 " use path to provide path to a character device; default is /dev/tpm0\n" 2386 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n" 2387 " not provided it will be searched for in /sys/class/misc/tpm?/device\n", 2388 QEMU_ARCH_ALL) 2389STEXI 2390 2391The general form of a TPM device option is: 2392@table @option 2393 2394@item -tpmdev @var{backend} ,id=@var{id} [,@var{options}] 2395@findex -tpmdev 2396Backend type must be: 2397@option{passthrough}. 2398 2399The specific backend type will determine the applicable options. 2400The @code{-tpmdev} option creates the TPM backend and requires a 2401@code{-device} option that specifies the TPM frontend interface model. 2402 2403Options to each backend are described below. 2404 2405Use 'help' to print all available TPM backend types. 2406@example 2407qemu -tpmdev help 2408@end example 2409 2410@item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path} 2411 2412(Linux-host only) Enable access to the host's TPM using the passthrough 2413driver. 2414 2415@option{path} specifies the path to the host's TPM device, i.e., on 2416a Linux host this would be @code{/dev/tpm0}. 2417@option{path} is optional and by default @code{/dev/tpm0} is used. 2418 2419@option{cancel-path} specifies the path to the host TPM device's sysfs 2420entry allowing for cancellation of an ongoing TPM command. 2421@option{cancel-path} is optional and by default QEMU will search for the 2422sysfs entry to use. 2423 2424Some notes about using the host's TPM with the passthrough driver: 2425 2426The TPM device accessed by the passthrough driver must not be 2427used by any other application on the host. 2428 2429Since the host's firmware (BIOS/UEFI) has already initialized the TPM, 2430the VM's firmware (BIOS/UEFI) will not be able to initialize the 2431TPM again and may therefore not show a TPM-specific menu that would 2432otherwise allow the user to configure the TPM, e.g., allow the user to 2433enable/disable or activate/deactivate the TPM. 2434Further, if TPM ownership is released from within a VM then the host's TPM 2435will get disabled and deactivated. To enable and activate the 2436TPM again afterwards, the host has to be rebooted and the user is 2437required to enter the firmware's menu to enable and activate the TPM. 2438If the TPM is left disabled and/or deactivated most TPM commands will fail. 2439 2440To create a passthrough TPM use the following two options: 2441@example 2442-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0 2443@end example 2444Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by 2445@code{tpmdev=tpm0} in the device option. 2446 2447@end table 2448 2449ETEXI 2450 2451DEFHEADING() 2452 2453#endif 2454 2455DEFHEADING(Linux/Multiboot boot specific:) 2456STEXI 2457 2458When using these options, you can use a given Linux or Multiboot 2459kernel without installing it in the disk image. It can be useful 2460for easier testing of various kernels. 2461 2462@table @option 2463ETEXI 2464 2465DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \ 2466 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL) 2467STEXI 2468@item -kernel @var{bzImage} 2469@findex -kernel 2470Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel 2471or in multiboot format. 2472ETEXI 2473 2474DEF("append", HAS_ARG, QEMU_OPTION_append, \ 2475 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL) 2476STEXI 2477@item -append @var{cmdline} 2478@findex -append 2479Use @var{cmdline} as kernel command line 2480ETEXI 2481 2482DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \ 2483 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL) 2484STEXI 2485@item -initrd @var{file} 2486@findex -initrd 2487Use @var{file} as initial ram disk. 2488 2489@item -initrd "@var{file1} arg=foo,@var{file2}" 2490 2491This syntax is only available with multiboot. 2492 2493Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the 2494first module. 2495ETEXI 2496 2497DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \ 2498 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL) 2499STEXI 2500@item -dtb @var{file} 2501@findex -dtb 2502Use @var{file} as a device tree binary (dtb) image and pass it to the kernel 2503on boot. 2504ETEXI 2505 2506STEXI 2507@end table 2508ETEXI 2509DEFHEADING() 2510 2511DEFHEADING(Debug/Expert options:) 2512STEXI 2513@table @option 2514ETEXI 2515 2516DEF("serial", HAS_ARG, QEMU_OPTION_serial, \ 2517 "-serial dev redirect the serial port to char device 'dev'\n", 2518 QEMU_ARCH_ALL) 2519STEXI 2520@item -serial @var{dev} 2521@findex -serial 2522Redirect the virtual serial port to host character device 2523@var{dev}. The default device is @code{vc} in graphical mode and 2524@code{stdio} in non graphical mode. 2525 2526This option can be used several times to simulate up to 4 serial 2527ports. 2528 2529Use @code{-serial none} to disable all serial ports. 2530 2531Available character devices are: 2532@table @option 2533@item vc[:@var{W}x@var{H}] 2534Virtual console. Optionally, a width and height can be given in pixel with 2535@example 2536vc:800x600 2537@end example 2538It is also possible to specify width or height in characters: 2539@example 2540vc:80Cx24C 2541@end example 2542@item pty 2543[Linux only] Pseudo TTY (a new PTY is automatically allocated) 2544@item none 2545No device is allocated. 2546@item null 2547void device 2548@item chardev:@var{id} 2549Use a named character device defined with the @code{-chardev} option. 2550@item /dev/XXX 2551[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port 2552parameters are set according to the emulated ones. 2553@item /dev/parport@var{N} 2554[Linux only, parallel port only] Use host parallel port 2555@var{N}. Currently SPP and EPP parallel port features can be used. 2556@item file:@var{filename} 2557Write output to @var{filename}. No character can be read. 2558@item stdio 2559[Unix only] standard input/output 2560@item pipe:@var{filename} 2561name pipe @var{filename} 2562@item COM@var{n} 2563[Windows only] Use host serial port @var{n} 2564@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}] 2565This implements UDP Net Console. 2566When @var{remote_host} or @var{src_ip} are not specified 2567they default to @code{0.0.0.0}. 2568When not using a specified @var{src_port} a random port is automatically chosen. 2569 2570If you just want a simple readonly console you can use @code{netcat} or 2571@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as: 2572@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it 2573will appear in the netconsole session. 2574 2575If you plan to send characters back via netconsole or you want to stop 2576and start QEMU a lot of times, you should have QEMU use the same 2577source port each time by using something like @code{-serial 2578udp::4555@@:4556} to QEMU. Another approach is to use a patched 2579version of netcat which can listen to a TCP port and send and receive 2580characters via udp. If you have a patched version of netcat which 2581activates telnet remote echo and single char transfer, then you can 2582use the following options to step up a netcat redirector to allow 2583telnet on port 5555 to access the QEMU port. 2584@table @code 2585@item QEMU Options: 2586-serial udp::4555@@:4556 2587@item netcat options: 2588-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T 2589@item telnet options: 2590localhost 5555 2591@end table 2592 2593@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay] 2594The TCP Net Console has two modes of operation. It can send the serial 2595I/O to a location or wait for a connection from a location. By default 2596the TCP Net Console is sent to @var{host} at the @var{port}. If you use 2597the @var{server} option QEMU will wait for a client socket application 2598to connect to the port before continuing, unless the @code{nowait} 2599option was specified. The @code{nodelay} option disables the Nagle buffering 2600algorithm. If @var{host} is omitted, 0.0.0.0 is assumed. Only 2601one TCP connection at a time is accepted. You can use @code{telnet} to 2602connect to the corresponding character device. 2603@table @code 2604@item Example to send tcp console to 192.168.0.2 port 4444 2605-serial tcp:192.168.0.2:4444 2606@item Example to listen and wait on port 4444 for connection 2607-serial tcp::4444,server 2608@item Example to not wait and listen on ip 192.168.0.100 port 4444 2609-serial tcp:192.168.0.100:4444,server,nowait 2610@end table 2611 2612@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay] 2613The telnet protocol is used instead of raw tcp sockets. The options 2614work the same as if you had specified @code{-serial tcp}. The 2615difference is that the port acts like a telnet server or client using 2616telnet option negotiation. This will also allow you to send the 2617MAGIC_SYSRQ sequence if you use a telnet that supports sending the break 2618sequence. Typically in unix telnet you do it with Control-] and then 2619type "send break" followed by pressing the enter key. 2620 2621@item unix:@var{path}[,server][,nowait] 2622A unix domain socket is used instead of a tcp socket. The option works the 2623same as if you had specified @code{-serial tcp} except the unix domain socket 2624@var{path} is used for connections. 2625 2626@item mon:@var{dev_string} 2627This is a special option to allow the monitor to be multiplexed onto 2628another serial port. The monitor is accessed with key sequence of 2629@key{Control-a} and then pressing @key{c}. 2630@var{dev_string} should be any one of the serial devices specified 2631above. An example to multiplex the monitor onto a telnet server 2632listening on port 4444 would be: 2633@table @code 2634@item -serial mon:telnet::4444,server,nowait 2635@end table 2636When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate 2637QEMU any more but will be passed to the guest instead. 2638 2639@item braille 2640Braille device. This will use BrlAPI to display the braille output on a real 2641or fake device. 2642 2643@item msmouse 2644Three button serial mouse. Configure the guest to use Microsoft protocol. 2645@end table 2646ETEXI 2647 2648DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \ 2649 "-parallel dev redirect the parallel port to char device 'dev'\n", 2650 QEMU_ARCH_ALL) 2651STEXI 2652@item -parallel @var{dev} 2653@findex -parallel 2654Redirect the virtual parallel port to host device @var{dev} (same 2655devices as the serial port). On Linux hosts, @file{/dev/parportN} can 2656be used to use hardware devices connected on the corresponding host 2657parallel port. 2658 2659This option can be used several times to simulate up to 3 parallel 2660ports. 2661 2662Use @code{-parallel none} to disable all parallel ports. 2663ETEXI 2664 2665DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \ 2666 "-monitor dev redirect the monitor to char device 'dev'\n", 2667 QEMU_ARCH_ALL) 2668STEXI 2669@item -monitor @var{dev} 2670@findex -monitor 2671Redirect the monitor to host device @var{dev} (same devices as the 2672serial port). 2673The default device is @code{vc} in graphical mode and @code{stdio} in 2674non graphical mode. 2675Use @code{-monitor none} to disable the default monitor. 2676ETEXI 2677DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \ 2678 "-qmp dev like -monitor but opens in 'control' mode\n", 2679 QEMU_ARCH_ALL) 2680STEXI 2681@item -qmp @var{dev} 2682@findex -qmp 2683Like -monitor but opens in 'control' mode. 2684ETEXI 2685 2686DEF("mon", HAS_ARG, QEMU_OPTION_mon, \ 2687 "-mon [chardev=]name[,mode=readline|control][,default]\n", QEMU_ARCH_ALL) 2688STEXI 2689@item -mon [chardev=]name[,mode=readline|control][,default] 2690@findex -mon 2691Setup monitor on chardev @var{name}. 2692ETEXI 2693 2694DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ 2695 "-debugcon dev redirect the debug console to char device 'dev'\n", 2696 QEMU_ARCH_ALL) 2697STEXI 2698@item -debugcon @var{dev} 2699@findex -debugcon 2700Redirect the debug console to host device @var{dev} (same devices as the 2701serial port). The debug console is an I/O port which is typically port 27020xe9; writing to that I/O port sends output to this device. 2703The default device is @code{vc} in graphical mode and @code{stdio} in 2704non graphical mode. 2705ETEXI 2706 2707DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ 2708 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL) 2709STEXI 2710@item -pidfile @var{file} 2711@findex -pidfile 2712Store the QEMU process PID in @var{file}. It is useful if you launch QEMU 2713from a script. 2714ETEXI 2715 2716DEF("singlestep", 0, QEMU_OPTION_singlestep, \ 2717 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) 2718STEXI 2719@item -singlestep 2720@findex -singlestep 2721Run the emulation in single step mode. 2722ETEXI 2723 2724DEF("S", 0, QEMU_OPTION_S, \ 2725 "-S freeze CPU at startup (use 'c' to start execution)\n", 2726 QEMU_ARCH_ALL) 2727STEXI 2728@item -S 2729@findex -S 2730Do not start CPU at startup (you must type 'c' in the monitor). 2731ETEXI 2732 2733DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, 2734 "-realtime [mlock=on|off]\n" 2735 " run qemu with realtime features\n" 2736 " mlock=on|off controls mlock support (default: on)\n", 2737 QEMU_ARCH_ALL) 2738STEXI 2739@item -realtime mlock=on|off 2740@findex -realtime 2741Run qemu with realtime features. 2742mlocking qemu and guest memory can be enabled via @option{mlock=on} 2743(enabled by default). 2744ETEXI 2745 2746DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ 2747 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) 2748STEXI 2749@item -gdb @var{dev} 2750@findex -gdb 2751Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical 2752connections will likely be TCP-based, but also UDP, pseudo TTY, or even 2753stdio are reasonable use case. The latter is allowing to start QEMU from 2754within gdb and establish the connection via a pipe: 2755@example 2756(gdb) target remote | exec qemu-system-i386 -gdb stdio ... 2757@end example 2758ETEXI 2759 2760DEF("s", 0, QEMU_OPTION_s, \ 2761 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n", 2762 QEMU_ARCH_ALL) 2763STEXI 2764@item -s 2765@findex -s 2766Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234 2767(@pxref{gdb_usage}). 2768ETEXI 2769 2770DEF("d", HAS_ARG, QEMU_OPTION_d, \ 2771 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n", 2772 QEMU_ARCH_ALL) 2773STEXI 2774@item -d @var{item1}[,...] 2775@findex -d 2776Enable logging of specified items. Use '-d help' for a list of log items. 2777ETEXI 2778 2779DEF("D", HAS_ARG, QEMU_OPTION_D, \ 2780 "-D logfile output log to logfile (default stderr)\n", 2781 QEMU_ARCH_ALL) 2782STEXI 2783@item -D @var{logfile} 2784@findex -D 2785Output log in @var{logfile} instead of to stderr 2786ETEXI 2787 2788DEF("L", HAS_ARG, QEMU_OPTION_L, \ 2789 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", 2790 QEMU_ARCH_ALL) 2791STEXI 2792@item -L @var{path} 2793@findex -L 2794Set the directory for the BIOS, VGA BIOS and keymaps. 2795ETEXI 2796 2797DEF("bios", HAS_ARG, QEMU_OPTION_bios, \ 2798 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL) 2799STEXI 2800@item -bios @var{file} 2801@findex -bios 2802Set the filename for the BIOS. 2803ETEXI 2804 2805DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \ 2806 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL) 2807STEXI 2808@item -enable-kvm 2809@findex -enable-kvm 2810Enable KVM full virtualization support. This option is only available 2811if KVM support is enabled when compiling. 2812ETEXI 2813 2814DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, 2815 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) 2816DEF("xen-create", 0, QEMU_OPTION_xen_create, 2817 "-xen-create create domain using xen hypercalls, bypassing xend\n" 2818 " warning: should not be used when xend is in use\n", 2819 QEMU_ARCH_ALL) 2820DEF("xen-attach", 0, QEMU_OPTION_xen_attach, 2821 "-xen-attach attach to existing xen domain\n" 2822 " xend will use this when starting QEMU\n", 2823 QEMU_ARCH_ALL) 2824STEXI 2825@item -xen-domid @var{id} 2826@findex -xen-domid 2827Specify xen guest domain @var{id} (XEN only). 2828@item -xen-create 2829@findex -xen-create 2830Create domain using xen hypercalls, bypassing xend. 2831Warning: should not be used when xend is in use (XEN only). 2832@item -xen-attach 2833@findex -xen-attach 2834Attach to existing xen domain. 2835xend will use this when starting QEMU (XEN only). 2836ETEXI 2837 2838DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \ 2839 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL) 2840STEXI 2841@item -no-reboot 2842@findex -no-reboot 2843Exit instead of rebooting. 2844ETEXI 2845 2846DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \ 2847 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL) 2848STEXI 2849@item -no-shutdown 2850@findex -no-shutdown 2851Don't exit QEMU on guest shutdown, but instead only stop the emulation. 2852This allows for instance switching to monitor to commit changes to the 2853disk image. 2854ETEXI 2855 2856DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ 2857 "-loadvm [tag|id]\n" \ 2858 " start right away with a saved state (loadvm in monitor)\n", 2859 QEMU_ARCH_ALL) 2860STEXI 2861@item -loadvm @var{file} 2862@findex -loadvm 2863Start right away with a saved state (@code{loadvm} in monitor) 2864ETEXI 2865 2866#ifndef _WIN32 2867DEF("daemonize", 0, QEMU_OPTION_daemonize, \ 2868 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) 2869#endif 2870STEXI 2871@item -daemonize 2872@findex -daemonize 2873Daemonize the QEMU process after initialization. QEMU will not detach from 2874standard IO until it is ready to receive connections on any of its devices. 2875This option is a useful way for external programs to launch QEMU without having 2876to cope with initialization race conditions. 2877ETEXI 2878 2879DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \ 2880 "-option-rom rom load a file, rom, into the option ROM space\n", 2881 QEMU_ARCH_ALL) 2882STEXI 2883@item -option-rom @var{file} 2884@findex -option-rom 2885Load the contents of @var{file} as an option ROM. 2886This option is useful to load things like EtherBoot. 2887ETEXI 2888 2889DEF("clock", HAS_ARG, QEMU_OPTION_clock, \ 2890 "-clock force the use of the given methods for timer alarm.\n" \ 2891 " To see what timers are available use '-clock help'\n", 2892 QEMU_ARCH_ALL) 2893STEXI 2894@item -clock @var{method} 2895@findex -clock 2896Force the use of the given methods for timer alarm. To see what timers 2897are available use @code{-clock help}. 2898ETEXI 2899 2900HXCOMM Options deprecated by -rtc 2901DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL) 2902DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL) 2903 2904DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \ 2905 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \ 2906 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n", 2907 QEMU_ARCH_ALL) 2908 2909STEXI 2910 2911@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew] 2912@findex -rtc 2913Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current 2914UTC or local time, respectively. @code{localtime} is required for correct date in 2915MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the 2916format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC. 2917 2918By default the RTC is driven by the host system time. This allows using of the 2919RTC as accurate reference clock inside the guest, specifically if the host 2920time is smoothly following an accurate external reference clock, e.g. via NTP. 2921If you want to isolate the guest time from the host, you can set @option{clock} 2922to @code{rt} instead. To even prevent it from progressing during suspension, 2923you can set it to @code{vm}. 2924 2925Enable @option{driftfix} (i386 targets only) if you experience time drift problems, 2926specifically with Windows' ACPI HAL. This option will try to figure out how 2927many timer interrupts were not processed by the Windows guest and will 2928re-inject them. 2929ETEXI 2930 2931DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ 2932 "-icount [N|auto]\n" \ 2933 " enable virtual instruction counter with 2^N clock ticks per\n" \ 2934 " instruction\n", QEMU_ARCH_ALL) 2935STEXI 2936@item -icount [@var{N}|auto] 2937@findex -icount 2938Enable virtual instruction counter. The virtual cpu will execute one 2939instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified 2940then the virtual cpu speed will be automatically adjusted to keep virtual 2941time within a few seconds of real time. 2942 2943Note that while this option can give deterministic behavior, it does not 2944provide cycle accurate emulation. Modern CPUs contain superscalar out of 2945order cores with complex cache hierarchies. The number of instructions 2946executed often has little or no correlation with actual performance. 2947ETEXI 2948 2949DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ 2950 "-watchdog i6300esb|ib700\n" \ 2951 " enable virtual hardware watchdog [default=none]\n", 2952 QEMU_ARCH_ALL) 2953STEXI 2954@item -watchdog @var{model} 2955@findex -watchdog 2956Create a virtual hardware watchdog device. Once enabled (by a guest 2957action), the watchdog must be periodically polled by an agent inside 2958the guest or else the guest will be restarted. 2959 2960The @var{model} is the model of hardware watchdog to emulate. Choices 2961for model are: @code{ib700} (iBASE 700) which is a very simple ISA 2962watchdog with a single timer, or @code{i6300esb} (Intel 6300ESB I/O 2963controller hub) which is a much more featureful PCI-based dual-timer 2964watchdog. Choose a model for which your guest has drivers. 2965 2966Use @code{-watchdog help} to list available hardware models. Only one 2967watchdog can be enabled for a guest. 2968ETEXI 2969 2970DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \ 2971 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \ 2972 " action when watchdog fires [default=reset]\n", 2973 QEMU_ARCH_ALL) 2974STEXI 2975@item -watchdog-action @var{action} 2976@findex -watchdog-action 2977 2978The @var{action} controls what QEMU will do when the watchdog timer 2979expires. 2980The default is 2981@code{reset} (forcefully reset the guest). 2982Other possible actions are: 2983@code{shutdown} (attempt to gracefully shutdown the guest), 2984@code{poweroff} (forcefully poweroff the guest), 2985@code{pause} (pause the guest), 2986@code{debug} (print a debug message and continue), or 2987@code{none} (do nothing). 2988 2989Note that the @code{shutdown} action requires that the guest responds 2990to ACPI signals, which it may not be able to do in the sort of 2991situations where the watchdog would have expired, and thus 2992@code{-watchdog-action shutdown} is not recommended for production use. 2993 2994Examples: 2995 2996@table @code 2997@item -watchdog i6300esb -watchdog-action pause 2998@item -watchdog ib700 2999@end table 3000ETEXI 3001 3002DEF("echr", HAS_ARG, QEMU_OPTION_echr, \ 3003 "-echr chr set terminal escape character instead of ctrl-a\n", 3004 QEMU_ARCH_ALL) 3005STEXI 3006 3007@item -echr @var{numeric_ascii_value} 3008@findex -echr 3009Change the escape character used for switching to the monitor when using 3010monitor and serial sharing. The default is @code{0x01} when using the 3011@code{-nographic} option. @code{0x01} is equal to pressing 3012@code{Control-a}. You can select a different character from the ascii 3013control keys where 1 through 26 map to Control-a through Control-z. For 3014instance you could use the either of the following to change the escape 3015character to Control-t. 3016@table @code 3017@item -echr 0x14 3018@item -echr 20 3019@end table 3020ETEXI 3021 3022DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \ 3023 "-virtioconsole c\n" \ 3024 " set virtio console\n", QEMU_ARCH_ALL) 3025STEXI 3026@item -virtioconsole @var{c} 3027@findex -virtioconsole 3028Set virtio console. 3029 3030This option is maintained for backward compatibility. 3031 3032Please use @code{-device virtconsole} for the new way of invocation. 3033ETEXI 3034 3035DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \ 3036 "-show-cursor show cursor\n", QEMU_ARCH_ALL) 3037STEXI 3038@item -show-cursor 3039@findex -show-cursor 3040Show cursor. 3041ETEXI 3042 3043DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \ 3044 "-tb-size n set TB size\n", QEMU_ARCH_ALL) 3045STEXI 3046@item -tb-size @var{n} 3047@findex -tb-size 3048Set TB size. 3049ETEXI 3050 3051DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \ 3052 "-incoming p prepare for incoming migration, listen on port p\n", 3053 QEMU_ARCH_ALL) 3054STEXI 3055@item -incoming @var{port} 3056@findex -incoming 3057Prepare for incoming migration, listen on @var{port}. 3058ETEXI 3059 3060DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \ 3061 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL) 3062STEXI 3063@item -nodefaults 3064@findex -nodefaults 3065Don't create default devices. Normally, QEMU sets the default devices like serial 3066port, parallel port, virtual console, monitor device, VGA adapter, floppy and 3067CD-ROM drive and others. The @code{-nodefaults} option will disable all those 3068default devices. 3069ETEXI 3070 3071#ifndef _WIN32 3072DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \ 3073 "-chroot dir chroot to dir just before starting the VM\n", 3074 QEMU_ARCH_ALL) 3075#endif 3076STEXI 3077@item -chroot @var{dir} 3078@findex -chroot 3079Immediately before starting guest execution, chroot to the specified 3080directory. Especially useful in combination with -runas. 3081ETEXI 3082 3083#ifndef _WIN32 3084DEF("runas", HAS_ARG, QEMU_OPTION_runas, \ 3085 "-runas user change to user id user just before starting the VM\n", 3086 QEMU_ARCH_ALL) 3087#endif 3088STEXI 3089@item -runas @var{user} 3090@findex -runas 3091Immediately before starting guest execution, drop root privileges, switching 3092to the specified user. 3093ETEXI 3094 3095DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env, 3096 "-prom-env variable=value\n" 3097 " set OpenBIOS nvram variables\n", 3098 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 3099STEXI 3100@item -prom-env @var{variable}=@var{value} 3101@findex -prom-env 3102Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only). 3103ETEXI 3104DEF("semihosting", 0, QEMU_OPTION_semihosting, 3105 "-semihosting semihosting mode\n", 3106 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32) 3107STEXI 3108@item -semihosting 3109@findex -semihosting 3110Semihosting mode (ARM, M68K, Xtensa only). 3111ETEXI 3112DEF("old-param", 0, QEMU_OPTION_old_param, 3113 "-old-param old param mode\n", QEMU_ARCH_ARM) 3114STEXI 3115@item -old-param 3116@findex -old-param (ARM) 3117Old param mode (ARM only). 3118ETEXI 3119 3120DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ 3121 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n", 3122 QEMU_ARCH_ALL) 3123STEXI 3124@item -sandbox @var{arg} 3125@findex -sandbox 3126Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will 3127disable it. The default is 'off'. 3128ETEXI 3129 3130DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, 3131 "-readconfig <file>\n", QEMU_ARCH_ALL) 3132STEXI 3133@item -readconfig @var{file} 3134@findex -readconfig 3135Read device configuration from @var{file}. This approach is useful when you want to spawn 3136QEMU process with many command line options but you don't want to exceed the command line 3137character limit. 3138ETEXI 3139DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig, 3140 "-writeconfig <file>\n" 3141 " read/write config file\n", QEMU_ARCH_ALL) 3142STEXI 3143@item -writeconfig @var{file} 3144@findex -writeconfig 3145Write device configuration to @var{file}. The @var{file} can be either filename to save 3146command line and device configuration into file or dash @code{-}) character to print the 3147output to stdout. This can be later used as input file for @code{-readconfig} option. 3148ETEXI 3149DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, 3150 "-nodefconfig\n" 3151 " do not load default config files at startup\n", 3152 QEMU_ARCH_ALL) 3153STEXI 3154@item -nodefconfig 3155@findex -nodefconfig 3156Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup. 3157The @code{-nodefconfig} option will prevent QEMU from loading any of those config files. 3158ETEXI 3159DEF("no-user-config", 0, QEMU_OPTION_nouserconfig, 3160 "-no-user-config\n" 3161 " do not load user-provided config files at startup\n", 3162 QEMU_ARCH_ALL) 3163STEXI 3164@item -no-user-config 3165@findex -no-user-config 3166The @code{-no-user-config} option makes QEMU not load any of the user-provided 3167config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config 3168files from @var{datadir}. 3169ETEXI 3170DEF("trace", HAS_ARG, QEMU_OPTION_trace, 3171 "-trace [events=<file>][,file=<file>]\n" 3172 " specify tracing options\n", 3173 QEMU_ARCH_ALL) 3174STEXI 3175HXCOMM This line is not accurate, as some sub-options are backend-specific but 3176HXCOMM HX does not support conditional compilation of text. 3177@item -trace [events=@var{file}][,file=@var{file}] 3178@findex -trace 3179 3180Specify tracing options. 3181 3182@table @option 3183@item events=@var{file} 3184Immediately enable events listed in @var{file}. 3185The file must contain one event name (as listed in the @var{trace-events} file) 3186per line. 3187This option is only available if QEMU has been compiled with 3188either @var{simple} or @var{stderr} tracing backend. 3189@item file=@var{file} 3190Log output traces to @var{file}. 3191 3192This option is only available if QEMU has been compiled with 3193the @var{simple} tracing backend. 3194@end table 3195ETEXI 3196 3197HXCOMM Internal use 3198DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL) 3199DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL) 3200 3201#ifdef __linux__ 3202DEF("enable-fips", 0, QEMU_OPTION_enablefips, 3203 "-enable-fips enable FIPS 140-2 compliance\n", 3204 QEMU_ARCH_ALL) 3205#endif 3206STEXI 3207@item -enable-fips 3208@findex -enable-fips 3209Enable FIPS 140-2 compliance mode. 3210ETEXI 3211 3212HXCOMM Deprecated by -machine accel=tcg property 3213DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386) 3214 3215HXCOMM Deprecated by kvm-pit driver properties 3216DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection, 3217 "", QEMU_ARCH_I386) 3218 3219HXCOMM Deprecated (ignored) 3220DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386) 3221 3222HXCOMM Deprecated by -machine kernel_irqchip=on|off property 3223DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386) 3224 3225HXCOMM Deprecated (ignored) 3226DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL) 3227 3228DEF("object", HAS_ARG, QEMU_OPTION_object, 3229 "-object TYPENAME[,PROP1=VALUE1,...]\n" 3230 " create an new object of type TYPENAME setting properties\n" 3231 " in the order they are specified. Note that the 'id'\n" 3232 " property must be set. These objects are placed in the\n" 3233 " '/objects' path.\n", 3234 QEMU_ARCH_ALL) 3235STEXI 3236@item -object @var{typename}[,@var{prop1}=@var{value1},...] 3237@findex -object 3238Create an new object of type @var{typename} setting properties 3239in the order they are specified. Note that the 'id' 3240property must be set. These objects are placed in the 3241'/objects' path. 3242ETEXI 3243 3244DEF("msg", HAS_ARG, QEMU_OPTION_msg, 3245 "-msg timestamp[=on|off]\n" 3246 " change the format of messages\n" 3247 " on|off controls leading timestamps (default:on)\n", 3248 QEMU_ARCH_ALL) 3249STEXI 3250@item -msg timestamp[=on|off] 3251@findex -msg 3252prepend a timestamp to each log message.(default:on) 3253ETEXI 3254 3255DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate, 3256 "-dump-vmstate <file>\n" 3257 " Output vmstate information in JSON format to file.\n" 3258 " Use the scripts/vmstate-static-checker.py file to\n" 3259 " check for possible regressions in migration code\n" 3260 " by comparing two such vmstate dumps.", 3261 QEMU_ARCH_ALL) 3262STEXI 3263@item -dump-vmstate @var{file} 3264@findex -dump-vmstate 3265Dump json-encoded vmstate information for current machine type to file 3266in @var{file} 3267ETEXI 3268 3269HXCOMM This is the last statement. Insert new options before this line! 3270STEXI 3271@end table 3272ETEXI 3273
