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|split controls accelerated irqchip support (default=off)\n" 36 " vmport=on|off|auto controls emulation of vmport (default: auto)\n" 37 " kvm_shadow_mem=size of KVM shadow MMU in bytes\n" 38 " dump-guest-core=on|off include guest memory in a core dump (default=on)\n" 39 " mem-merge=on|off controls memory merge support (default: on)\n" 40 " igd-passthru=on|off controls IGD GFX passthrough support (default=off)\n" 41 " aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n" 42 " dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n" 43 " suppress-vmdesc=on|off disables self-describing migration (default=off)\n" 44 " nvdimm=on|off controls NVDIMM support (default=off)\n" 45 " enforce-config-section=on|off enforce configuration section migration (default=off)\n", 46 QEMU_ARCH_ALL) 47STEXI 48@item -machine [type=]@var{name}[,prop=@var{value}[,...]] 49@findex -machine 50Select the emulated machine by @var{name}. Use @code{-machine help} to list 51available machines. Supported machine properties are: 52@table @option 53@item accel=@var{accels1}[:@var{accels2}[:...]] 54This is used to enable an accelerator. Depending on the target architecture, 55kvm, xen, or tcg can be available. By default, tcg is used. If there is more 56than one accelerator specified, the next one is used if the previous one fails 57to initialize. 58@item kernel_irqchip=on|off 59Controls in-kernel irqchip support for the chosen accelerator when available. 60@item gfx_passthru=on|off 61Enables IGD GFX passthrough support for the chosen machine when available. 62@item vmport=on|off|auto 63Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the 64value based on accel. For accel=xen the default is off otherwise the default 65is on. 66@item kvm_shadow_mem=size 67Defines the size of the KVM shadow MMU. 68@item dump-guest-core=on|off 69Include guest memory in a core dump. The default is on. 70@item mem-merge=on|off 71Enables or disables memory merge support. This feature, when supported by 72the host, de-duplicates identical memory pages among VMs instances 73(enabled by default). 74@item aes-key-wrap=on|off 75Enables or disables AES key wrapping support on s390-ccw hosts. This feature 76controls whether AES wrapping keys will be created to allow 77execution of AES cryptographic functions. The default is on. 78@item dea-key-wrap=on|off 79Enables or disables DEA key wrapping support on s390-ccw hosts. This feature 80controls whether DEA wrapping keys will be created to allow 81execution of DEA cryptographic functions. The default is on. 82@item nvdimm=on|off 83Enables or disables NVDIMM support. The default is off. 84@end table 85ETEXI 86 87HXCOMM Deprecated by -machine 88DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL) 89 90DEF("cpu", HAS_ARG, QEMU_OPTION_cpu, 91 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL) 92STEXI 93@item -cpu @var{model} 94@findex -cpu 95Select CPU model (@code{-cpu help} for list and additional feature selection) 96ETEXI 97 98DEF("accel", HAS_ARG, QEMU_OPTION_accel, 99 "-accel [accel=]accelerator[,thread=single|multi]\n" 100 " select accelerator ('-accel help for list')\n" 101 " thread=single|multi (enable multi-threaded TCG)", QEMU_ARCH_ALL) 102STEXI 103@item -accel @var{name}[,prop=@var{value}[,...]] 104@findex -accel 105This is used to enable an accelerator. Depending on the target architecture, 106kvm, xen, or tcg can be available. By default, tcg is used. If there is more 107than one accelerator specified, the next one is used if the previous one fails 108to initialize. 109@table @option 110@item thread=single|multi 111Controls number of TCG threads. When the TCG is multi-threaded there will be one 112thread per vCPU therefor taking advantage of additional host cores. The default 113is to enable multi-threading where both the back-end and front-ends support it and 114no incompatible TCG features have been enabled (e.g. icount/replay). 115@end table 116ETEXI 117 118DEF("smp", HAS_ARG, QEMU_OPTION_smp, 119 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n" 120 " set the number of CPUs to 'n' [default=1]\n" 121 " maxcpus= maximum number of total cpus, including\n" 122 " offline CPUs for hotplug, etc\n" 123 " cores= number of CPU cores on one socket\n" 124 " threads= number of threads on one CPU core\n" 125 " sockets= number of discrete sockets in the system\n", 126 QEMU_ARCH_ALL) 127STEXI 128@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}] 129@findex -smp 130Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255 131CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs 132to 4. 133For the PC target, the number of @var{cores} per socket, the number 134of @var{threads} per cores and the total number of @var{sockets} can be 135specified. Missing values will be computed. If any on the three values is 136given, the total number of CPUs @var{n} can be omitted. @var{maxcpus} 137specifies the maximum number of hotpluggable CPUs. 138ETEXI 139 140DEF("numa", HAS_ARG, QEMU_OPTION_numa, 141 "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n" 142 "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n", QEMU_ARCH_ALL) 143STEXI 144@item -numa node[,mem=@var{size}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}] 145@itemx -numa node[,memdev=@var{id}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}] 146@findex -numa 147Simulate a multi node NUMA system. If @samp{mem}, @samp{memdev} 148and @samp{cpus} are omitted, resources are split equally. Also, note 149that the -@option{numa} option doesn't allocate any of the specified 150resources. That is, it just assigns existing resources to NUMA nodes. This 151means that one still has to use the @option{-m}, @option{-smp} options 152to allocate RAM and VCPUs respectively, and possibly @option{-object} 153to specify the memory backend for the @samp{memdev} suboption. 154 155@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, if one 156node uses @samp{memdev}, all of them have to use it. 157ETEXI 158 159DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd, 160 "-add-fd fd=fd,set=set[,opaque=opaque]\n" 161 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL) 162STEXI 163@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}] 164@findex -add-fd 165 166Add a file descriptor to an fd set. Valid options are: 167 168@table @option 169@item fd=@var{fd} 170This option defines the file descriptor of which a duplicate is added to fd set. 171The file descriptor cannot be stdin, stdout, or stderr. 172@item set=@var{set} 173This option defines the ID of the fd set to add the file descriptor to. 174@item opaque=@var{opaque} 175This option defines a free-form string that can be used to describe @var{fd}. 176@end table 177 178You can open an image using pre-opened file descriptors from an fd set: 179@example 180qemu-system-i386 181-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 182-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 183-drive file=/dev/fdset/2,index=0,media=disk 184@end example 185ETEXI 186 187DEF("set", HAS_ARG, QEMU_OPTION_set, 188 "-set group.id.arg=value\n" 189 " set <arg> parameter for item <id> of type <group>\n" 190 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL) 191STEXI 192@item -set @var{group}.@var{id}.@var{arg}=@var{value} 193@findex -set 194Set parameter @var{arg} for item @var{id} of type @var{group} 195ETEXI 196 197DEF("global", HAS_ARG, QEMU_OPTION_global, 198 "-global driver.property=value\n" 199 "-global driver=driver,property=property,value=value\n" 200 " set a global default for a driver property\n", 201 QEMU_ARCH_ALL) 202STEXI 203@item -global @var{driver}.@var{prop}=@var{value} 204@itemx -global driver=@var{driver},property=@var{property},value=@var{value} 205@findex -global 206Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.: 207 208@example 209qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk 210@end example 211 212In particular, you can use this to set driver properties for devices which are 213created automatically by the machine model. To create a device which is not 214created automatically and set properties on it, use -@option{device}. 215 216-global @var{driver}.@var{prop}=@var{value} is shorthand for -global 217driver=@var{driver},property=@var{prop},value=@var{value}. The 218longhand syntax works even when @var{driver} contains a dot. 219ETEXI 220 221DEF("boot", HAS_ARG, QEMU_OPTION_boot, 222 "-boot [order=drives][,once=drives][,menu=on|off]\n" 223 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n" 224 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n" 225 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n" 226 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n" 227 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n", 228 QEMU_ARCH_ALL) 229STEXI 230@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] 231@findex -boot 232Specify boot order @var{drives} as a string of drive letters. Valid 233drive letters depend on the target architecture. The x86 PC uses: a, b 234(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot 235from network adapter 1-4), hard disk boot is the default. To apply a 236particular boot order only on the first startup, specify it via 237@option{once}. 238 239Interactive boot menus/prompts can be enabled via @option{menu=on} as far 240as firmware/BIOS supports them. The default is non-interactive boot. 241 242A splash picture could be passed to bios, enabling user to show it as logo, 243when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS 244supports them. Currently Seabios for X86 system support it. 245limitation: The splash file could be a jpeg file or a BMP file in 24 BPP 246format(true color). The resolution should be supported by the SVGA mode, so 247the recommended is 320x240, 640x480, 800x640. 248 249A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms 250when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not 251reboot, qemu passes '-1' to bios by default. Currently Seabios for X86 252system support it. 253 254Do strict boot via @option{strict=on} as far as firmware/BIOS 255supports it. This only effects when boot priority is changed by 256bootindex options. The default is non-strict boot. 257 258@example 259# try to boot from network first, then from hard disk 260qemu-system-i386 -boot order=nc 261# boot from CD-ROM first, switch back to default order after reboot 262qemu-system-i386 -boot once=d 263# boot with a splash picture for 5 seconds. 264qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000 265@end example 266 267Note: The legacy format '-boot @var{drives}' is still supported but its 268use is discouraged as it may be removed from future versions. 269ETEXI 270 271DEF("m", HAS_ARG, QEMU_OPTION_m, 272 "-m [size=]megs[,slots=n,maxmem=size]\n" 273 " configure guest RAM\n" 274 " size: initial amount of guest memory\n" 275 " slots: number of hotplug slots (default: none)\n" 276 " maxmem: maximum amount of guest memory (default: none)\n" 277 "NOTE: Some architectures might enforce a specific granularity\n", 278 QEMU_ARCH_ALL) 279STEXI 280@item -m [size=]@var{megs}[,slots=n,maxmem=size] 281@findex -m 282Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB. 283Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in 284megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem} 285could be used to set amount of hotpluggable memory slots and maximum amount of 286memory. Note that @var{maxmem} must be aligned to the page size. 287 288For example, the following command-line sets the guest startup RAM size to 2891GB, creates 3 slots to hotplug additional memory and sets the maximum 290memory the guest can reach to 4GB: 291 292@example 293qemu-system-x86_64 -m 1G,slots=3,maxmem=4G 294@end example 295 296If @var{slots} and @var{maxmem} are not specified, memory hotplug won't 297be enabled and the guest startup RAM will never increase. 298ETEXI 299 300DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath, 301 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL) 302STEXI 303@item -mem-path @var{path} 304@findex -mem-path 305Allocate guest RAM from a temporarily created file in @var{path}. 306ETEXI 307 308DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc, 309 "-mem-prealloc preallocate guest memory (use with -mem-path)\n", 310 QEMU_ARCH_ALL) 311STEXI 312@item -mem-prealloc 313@findex -mem-prealloc 314Preallocate memory when using -mem-path. 315ETEXI 316 317DEF("k", HAS_ARG, QEMU_OPTION_k, 318 "-k language use keyboard layout (for example 'fr' for French)\n", 319 QEMU_ARCH_ALL) 320STEXI 321@item -k @var{language} 322@findex -k 323Use keyboard layout @var{language} (for example @code{fr} for 324French). This option is only needed where it is not easy to get raw PC 325keycodes (e.g. on Macs, with some X11 servers or with a VNC or curses 326display). You don't normally need to use it on PC/Linux or PC/Windows 327hosts. 328 329The available layouts are: 330@example 331ar de-ch es fo fr-ca hu ja mk no pt-br sv 332da en-gb et fr fr-ch is lt nl pl ru th 333de en-us fi fr-be hr it lv nl-be pt sl tr 334@end example 335 336The default is @code{en-us}. 337ETEXI 338 339 340DEF("audio-help", 0, QEMU_OPTION_audio_help, 341 "-audio-help print list of audio drivers and their options\n", 342 QEMU_ARCH_ALL) 343STEXI 344@item -audio-help 345@findex -audio-help 346Will show the audio subsystem help: list of drivers, tunable 347parameters. 348ETEXI 349 350DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw, 351 "-soundhw c1,... enable audio support\n" 352 " and only specified sound cards (comma separated list)\n" 353 " use '-soundhw help' to get the list of supported cards\n" 354 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL) 355STEXI 356@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all 357@findex -soundhw 358Enable audio and selected sound hardware. Use 'help' to print all 359available sound hardware. 360 361@example 362qemu-system-i386 -soundhw sb16,adlib disk.img 363qemu-system-i386 -soundhw es1370 disk.img 364qemu-system-i386 -soundhw ac97 disk.img 365qemu-system-i386 -soundhw hda disk.img 366qemu-system-i386 -soundhw all disk.img 367qemu-system-i386 -soundhw help 368@end example 369 370Note that Linux's i810_audio OSS kernel (for AC97) module might 371require manually specifying clocking. 372 373@example 374modprobe i810_audio clocking=48000 375@end example 376ETEXI 377 378DEF("balloon", HAS_ARG, QEMU_OPTION_balloon, 379 "-balloon none disable balloon device\n" 380 "-balloon virtio[,addr=str]\n" 381 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL) 382STEXI 383@item -balloon none 384@findex -balloon 385Disable balloon device. 386@item -balloon virtio[,addr=@var{addr}] 387Enable virtio balloon device (default), optionally with PCI address 388@var{addr}. 389ETEXI 390 391DEF("device", HAS_ARG, QEMU_OPTION_device, 392 "-device driver[,prop[=value][,...]]\n" 393 " add device (based on driver)\n" 394 " prop=value,... sets driver properties\n" 395 " use '-device help' to print all possible drivers\n" 396 " use '-device driver,help' to print all possible properties\n", 397 QEMU_ARCH_ALL) 398STEXI 399@item -device @var{driver}[,@var{prop}[=@var{value}][,...]] 400@findex -device 401Add device @var{driver}. @var{prop}=@var{value} sets driver 402properties. Valid properties depend on the driver. To get help on 403possible drivers and properties, use @code{-device help} and 404@code{-device @var{driver},help}. 405 406Some drivers are: 407@item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}] 408 409Add an IPMI BMC. This is a simulation of a hardware management 410interface processor that normally sits on a system. It provides 411a watchdog and the ability to reset and power control the system. 412You need to connect this to an IPMI interface to make it useful 413 414The IPMI slave address to use for the BMC. The default is 0x20. 415This address is the BMC's address on the I2C network of management 416controllers. If you don't know what this means, it is safe to ignore 417it. 418 419@item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}] 420 421Add a connection to an external IPMI BMC simulator. Instead of 422locally emulating the BMC like the above item, instead connect 423to an external entity that provides the IPMI services. 424 425A connection is made to an external BMC simulator. If you do this, it 426is strongly recommended that you use the "reconnect=" chardev option 427to reconnect to the simulator if the connection is lost. Note that if 428this is not used carefully, it can be a security issue, as the 429interface has the ability to send resets, NMIs, and power off the VM. 430It's best if QEMU makes a connection to an external simulator running 431on a secure port on localhost, so neither the simulator nor QEMU is 432exposed to any outside network. 433 434See the "lanserv/README.vm" file in the OpenIPMI library for more 435details on the external interface. 436 437@item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 438 439Add a KCS IPMI interafce on the ISA bus. This also adds a 440corresponding ACPI and SMBIOS entries, if appropriate. 441 442@table @option 443@item bmc=@var{id} 444The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above. 445@item ioport=@var{val} 446Define the I/O address of the interface. The default is 0xca0 for KCS. 447@item irq=@var{val} 448Define the interrupt to use. The default is 5. To disable interrupts, 449set this to 0. 450@end table 451 452@item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 453 454Like the KCS interface, but defines a BT interface. The default port is 4550xe4 and the default interrupt is 5. 456 457ETEXI 458 459DEF("name", HAS_ARG, QEMU_OPTION_name, 460 "-name string1[,process=string2][,debug-threads=on|off]\n" 461 " set the name of the guest\n" 462 " string1 sets the window title and string2 the process name (on Linux)\n" 463 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n" 464 " NOTE: The thread names are for debugging and not a stable API.\n", 465 QEMU_ARCH_ALL) 466STEXI 467@item -name @var{name} 468@findex -name 469Sets the @var{name} of the guest. 470This name will be displayed in the SDL window caption. 471The @var{name} will also be used for the VNC server. 472Also optionally set the top visible process name in Linux. 473Naming of individual threads can also be enabled on Linux to aid debugging. 474ETEXI 475 476DEF("uuid", HAS_ARG, QEMU_OPTION_uuid, 477 "-uuid %08x-%04x-%04x-%04x-%012x\n" 478 " specify machine UUID\n", QEMU_ARCH_ALL) 479STEXI 480@item -uuid @var{uuid} 481@findex -uuid 482Set system UUID. 483ETEXI 484 485STEXI 486@end table 487ETEXI 488DEFHEADING() 489 490DEFHEADING(Block device options) 491STEXI 492@table @option 493ETEXI 494 495DEF("fda", HAS_ARG, QEMU_OPTION_fda, 496 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL) 497DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL) 498STEXI 499@item -fda @var{file} 500@itemx -fdb @var{file} 501@findex -fda 502@findex -fdb 503Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). 504ETEXI 505 506DEF("hda", HAS_ARG, QEMU_OPTION_hda, 507 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL) 508DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL) 509DEF("hdc", HAS_ARG, QEMU_OPTION_hdc, 510 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL) 511DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL) 512STEXI 513@item -hda @var{file} 514@itemx -hdb @var{file} 515@itemx -hdc @var{file} 516@itemx -hdd @var{file} 517@findex -hda 518@findex -hdb 519@findex -hdc 520@findex -hdd 521Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}). 522ETEXI 523 524DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom, 525 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n", 526 QEMU_ARCH_ALL) 527STEXI 528@item -cdrom @var{file} 529@findex -cdrom 530Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and 531@option{-cdrom} at the same time). You can use the host CD-ROM by 532using @file{/dev/cdrom} as filename (@pxref{host_drives}). 533ETEXI 534 535DEF("drive", HAS_ARG, QEMU_OPTION_drive, 536 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" 537 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n" 538 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n" 539 " [,serial=s][,addr=A][,rerror=ignore|stop|report]\n" 540 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n" 541 " [,readonly=on|off][,copy-on-read=on|off]\n" 542 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n" 543 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n" 544 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n" 545 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n" 546 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n" 547 " [[,iops_size=is]]\n" 548 " [[,group=g]]\n" 549 " use 'file' as a drive image\n", QEMU_ARCH_ALL) 550STEXI 551@item -drive @var{option}[,@var{option}[,@var{option}[,...]]] 552@findex -drive 553 554Define a new drive. Valid options are: 555 556@table @option 557@item file=@var{file} 558This option defines which disk image (@pxref{disk_images}) to use with 559this drive. If the filename contains comma, you must double it 560(for instance, "file=my,,file" to use file "my,file"). 561 562Special files such as iSCSI devices can be specified using protocol 563specific URLs. See the section for "Device URL Syntax" for more information. 564@item if=@var{interface} 565This option defines on which type on interface the drive is connected. 566Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio. 567@item bus=@var{bus},unit=@var{unit} 568These options define where is connected the drive by defining the bus number and 569the unit id. 570@item index=@var{index} 571This option defines where is connected the drive by using an index in the list 572of available connectors of a given interface type. 573@item media=@var{media} 574This option defines the type of the media: disk or cdrom. 575@item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}] 576These options have the same definition as they have in @option{-hdachs}. 577@item snapshot=@var{snapshot} 578@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive 579(see @option{-snapshot}). 580@item cache=@var{cache} 581@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data. 582@item aio=@var{aio} 583@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO. 584@item discard=@var{discard} 585@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. 586@item format=@var{format} 587Specify which disk @var{format} will be used rather than detecting 588the format. Can be used to specify format=raw to avoid interpreting 589an untrusted format header. 590@item serial=@var{serial} 591This option specifies the serial number to assign to the device. 592@item addr=@var{addr} 593Specify the controller's PCI address (if=virtio only). 594@item werror=@var{action},rerror=@var{action} 595Specify which @var{action} to take on write and read errors. Valid actions are: 596"ignore" (ignore the error and try to continue), "stop" (pause QEMU), 597"report" (report the error to the guest), "enospc" (pause QEMU only if the 598host disk is full; report the error to the guest otherwise). 599The default setting is @option{werror=enospc} and @option{rerror=report}. 600@item readonly 601Open drive @option{file} as read-only. Guest write attempts will fail. 602@item copy-on-read=@var{copy-on-read} 603@var{copy-on-read} is "on" or "off" and enables whether to copy read backing 604file sectors into the image file. 605@item detect-zeroes=@var{detect-zeroes} 606@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic 607conversion of plain zero writes by the OS to driver specific optimized 608zero write commands. You may even choose "unmap" if @var{discard} is set 609to "unmap" to allow a zero write to be converted to an UNMAP operation. 610@end table 611 612By default, the @option{cache=writeback} mode is used. It will report data 613writes as completed as soon as the data is present in the host page cache. 614This is safe as long as your guest OS makes sure to correctly flush disk caches 615where needed. If your guest OS does not handle volatile disk write caches 616correctly and your host crashes or loses power, then the guest may experience 617data corruption. 618 619For such guests, you should consider using @option{cache=writethrough}. This 620means that the host page cache will be used to read and write data, but write 621notification will be sent to the guest only after QEMU has made sure to flush 622each write to the disk. Be aware that this has a major impact on performance. 623 624The host page cache can be avoided entirely with @option{cache=none}. This will 625attempt to do disk IO directly to the guest's memory. QEMU may still perform 626an internal copy of the data. Note that this is considered a writeback mode and 627the guest OS must handle the disk write cache correctly in order to avoid data 628corruption on host crashes. 629 630The host page cache can be avoided while only sending write notifications to 631the guest when the data has been flushed to the disk using 632@option{cache=directsync}. 633 634In case you don't care about data integrity over host failures, use 635@option{cache=unsafe}. This option tells QEMU that it never needs to write any 636data to the disk but can instead keep things in cache. If anything goes wrong, 637like your host losing power, the disk storage getting disconnected accidentally, 638etc. your image will most probably be rendered unusable. When using 639the @option{-snapshot} option, unsafe caching is always used. 640 641Copy-on-read avoids accessing the same backing file sectors repeatedly and is 642useful when the backing file is over a slow network. By default copy-on-read 643is off. 644 645Instead of @option{-cdrom} you can use: 646@example 647qemu-system-i386 -drive file=file,index=2,media=cdrom 648@end example 649 650Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can 651use: 652@example 653qemu-system-i386 -drive file=file,index=0,media=disk 654qemu-system-i386 -drive file=file,index=1,media=disk 655qemu-system-i386 -drive file=file,index=2,media=disk 656qemu-system-i386 -drive file=file,index=3,media=disk 657@end example 658 659You can open an image using pre-opened file descriptors from an fd set: 660@example 661qemu-system-i386 662-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 663-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 664-drive file=/dev/fdset/2,index=0,media=disk 665@end example 666 667You can connect a CDROM to the slave of ide0: 668@example 669qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom 670@end example 671 672If you don't specify the "file=" argument, you define an empty drive: 673@example 674qemu-system-i386 -drive if=ide,index=1,media=cdrom 675@end example 676 677Instead of @option{-fda}, @option{-fdb}, you can use: 678@example 679qemu-system-i386 -drive file=file,index=0,if=floppy 680qemu-system-i386 -drive file=file,index=1,if=floppy 681@end example 682 683By default, @var{interface} is "ide" and @var{index} is automatically 684incremented: 685@example 686qemu-system-i386 -drive file=a -drive file=b" 687@end example 688is interpreted like: 689@example 690qemu-system-i386 -hda a -hdb b 691@end example 692ETEXI 693 694DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock, 695 "-mtdblock file use 'file' as on-board Flash memory image\n", 696 QEMU_ARCH_ALL) 697STEXI 698@item -mtdblock @var{file} 699@findex -mtdblock 700Use @var{file} as on-board Flash memory image. 701ETEXI 702 703DEF("sd", HAS_ARG, QEMU_OPTION_sd, 704 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL) 705STEXI 706@item -sd @var{file} 707@findex -sd 708Use @var{file} as SecureDigital card image. 709ETEXI 710 711DEF("pflash", HAS_ARG, QEMU_OPTION_pflash, 712 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL) 713STEXI 714@item -pflash @var{file} 715@findex -pflash 716Use @var{file} as a parallel flash image. 717ETEXI 718 719DEF("snapshot", 0, QEMU_OPTION_snapshot, 720 "-snapshot write to temporary files instead of disk image files\n", 721 QEMU_ARCH_ALL) 722STEXI 723@item -snapshot 724@findex -snapshot 725Write to temporary files instead of disk image files. In this case, 726the raw disk image you use is not written back. You can however force 727the write back by pressing @key{C-a s} (@pxref{disk_images}). 728ETEXI 729 730DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \ 731 "-hdachs c,h,s[,t]\n" \ 732 " force hard disk 0 physical geometry and the optional BIOS\n" \ 733 " translation (t=none or lba) (usually QEMU can guess them)\n", 734 QEMU_ARCH_ALL) 735STEXI 736@item -hdachs @var{c},@var{h},@var{s},[,@var{t}] 737@findex -hdachs 738Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <= 739@var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS 740translation mode (@var{t}=none, lba or auto). Usually QEMU can guess 741all those parameters. This option is useful for old MS-DOS disk 742images. 743ETEXI 744 745DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev, 746 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n" 747 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n" 748 " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n" 749 " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n" 750 " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n" 751 " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n" 752 " [[,throttling.iops-size=is]]\n", 753 QEMU_ARCH_ALL) 754 755STEXI 756 757@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}] 758@findex -fsdev 759Define a new file system device. Valid options are: 760@table @option 761@item @var{fsdriver} 762This option specifies the fs driver backend to use. 763Currently "local", "handle" and "proxy" file system drivers are supported. 764@item id=@var{id} 765Specifies identifier for this device 766@item path=@var{path} 767Specifies the export path for the file system device. Files under 768this path will be available to the 9p client on the guest. 769@item security_model=@var{security_model} 770Specifies the security model to be used for this export path. 771Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 772In "passthrough" security model, files are stored using the same 773credentials as they are created on the guest. This requires QEMU 774to run as root. In "mapped-xattr" security model, some of the file 775attributes like uid, gid, mode bits and link target are stored as 776file attributes. For "mapped-file" these attributes are stored in the 777hidden .virtfs_metadata directory. Directories exported by this security model cannot 778interact with other unix tools. "none" security model is same as 779passthrough except the sever won't report failures if it fails to 780set file attributes like ownership. Security model is mandatory 781only for local fsdriver. Other fsdrivers (like handle, proxy) don't take 782security model as a parameter. 783@item writeout=@var{writeout} 784This is an optional argument. The only supported value is "immediate". 785This means that host page cache will be used to read and write data but 786write notification will be sent to the guest only when the data has been 787reported as written by the storage subsystem. 788@item readonly 789Enables exporting 9p share as a readonly mount for guests. By default 790read-write access is given. 791@item socket=@var{socket} 792Enables proxy filesystem driver to use passed socket file for communicating 793with virtfs-proxy-helper 794@item sock_fd=@var{sock_fd} 795Enables proxy filesystem driver to use passed socket descriptor for 796communicating with virtfs-proxy-helper. Usually a helper like libvirt 797will create socketpair and pass one of the fds as sock_fd 798@end table 799 800-fsdev option is used along with -device driver "virtio-9p-pci". 801@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag} 802Options for virtio-9p-pci driver are: 803@table @option 804@item fsdev=@var{id} 805Specifies the id value specified along with -fsdev option 806@item mount_tag=@var{mount_tag} 807Specifies the tag name to be used by the guest to mount this export point 808@end table 809 810ETEXI 811 812DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs, 813 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n" 814 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n", 815 QEMU_ARCH_ALL) 816 817STEXI 818 819@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}] 820@findex -virtfs 821 822The general form of a Virtual File system pass-through options are: 823@table @option 824@item @var{fsdriver} 825This option specifies the fs driver backend to use. 826Currently "local", "handle" and "proxy" file system drivers are supported. 827@item id=@var{id} 828Specifies identifier for this device 829@item path=@var{path} 830Specifies the export path for the file system device. Files under 831this path will be available to the 9p client on the guest. 832@item security_model=@var{security_model} 833Specifies the security model to be used for this export path. 834Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 835In "passthrough" security model, files are stored using the same 836credentials as they are created on the guest. This requires QEMU 837to run as root. In "mapped-xattr" security model, some of the file 838attributes like uid, gid, mode bits and link target are stored as 839file attributes. For "mapped-file" these attributes are stored in the 840hidden .virtfs_metadata directory. Directories exported by this security model cannot 841interact with other unix tools. "none" security model is same as 842passthrough except the sever won't report failures if it fails to 843set file attributes like ownership. Security model is mandatory only 844for local fsdriver. Other fsdrivers (like handle, proxy) don't take security 845model as a parameter. 846@item writeout=@var{writeout} 847This is an optional argument. The only supported value is "immediate". 848This means that host page cache will be used to read and write data but 849write notification will be sent to the guest only when the data has been 850reported as written by the storage subsystem. 851@item readonly 852Enables exporting 9p share as a readonly mount for guests. By default 853read-write access is given. 854@item socket=@var{socket} 855Enables proxy filesystem driver to use passed socket file for 856communicating with virtfs-proxy-helper. Usually a helper like libvirt 857will create socketpair and pass one of the fds as sock_fd 858@item sock_fd 859Enables proxy filesystem driver to use passed 'sock_fd' as the socket 860descriptor for interfacing with virtfs-proxy-helper 861@end table 862ETEXI 863 864DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth, 865 "-virtfs_synth Create synthetic file system image\n", 866 QEMU_ARCH_ALL) 867STEXI 868@item -virtfs_synth 869@findex -virtfs_synth 870Create synthetic file system image 871ETEXI 872 873STEXI 874@end table 875ETEXI 876DEFHEADING() 877 878DEFHEADING(USB options) 879STEXI 880@table @option 881ETEXI 882 883DEF("usb", 0, QEMU_OPTION_usb, 884 "-usb enable the USB driver (will be the default soon)\n", 885 QEMU_ARCH_ALL) 886STEXI 887@item -usb 888@findex -usb 889Enable the USB driver (will be the default soon) 890ETEXI 891 892DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice, 893 "-usbdevice name add the host or guest USB device 'name'\n", 894 QEMU_ARCH_ALL) 895STEXI 896 897@item -usbdevice @var{devname} 898@findex -usbdevice 899Add the USB device @var{devname}. @xref{usb_devices}. 900 901@table @option 902 903@item mouse 904Virtual Mouse. This will override the PS/2 mouse emulation when activated. 905 906@item tablet 907Pointer device that uses absolute coordinates (like a touchscreen). This 908means QEMU is able to report the mouse position without having to grab the 909mouse. Also overrides the PS/2 mouse emulation when activated. 910 911@item disk:[format=@var{format}]:@var{file} 912Mass storage device based on file. The optional @var{format} argument 913will be used rather than detecting the format. Can be used to specify 914@code{format=raw} to avoid interpreting an untrusted format header. 915 916@item host:@var{bus}.@var{addr} 917Pass through the host device identified by @var{bus}.@var{addr} (Linux only). 918 919@item host:@var{vendor_id}:@var{product_id} 920Pass through the host device identified by @var{vendor_id}:@var{product_id} 921(Linux only). 922 923@item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev} 924Serial converter to host character device @var{dev}, see @code{-serial} for the 925available devices. 926 927@item braille 928Braille device. This will use BrlAPI to display the braille output on a real 929or fake device. 930 931@item net:@var{options} 932Network adapter that supports CDC ethernet and RNDIS protocols. 933 934@end table 935ETEXI 936 937STEXI 938@end table 939ETEXI 940DEFHEADING() 941 942DEFHEADING(Display options) 943STEXI 944@table @option 945ETEXI 946 947DEF("display", HAS_ARG, QEMU_OPTION_display, 948 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n" 949 " [,window_close=on|off][,gl=on|off]\n" 950 "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n" 951 "-display vnc=<display>[,<optargs>]\n" 952 "-display curses\n" 953 "-display none" 954 " select display type\n" 955 "The default display is equivalent to\n" 956#if defined(CONFIG_GTK) 957 "\t\"-display gtk\"\n" 958#elif defined(CONFIG_SDL) 959 "\t\"-display sdl\"\n" 960#elif defined(CONFIG_COCOA) 961 "\t\"-display cocoa\"\n" 962#elif defined(CONFIG_VNC) 963 "\t\"-vnc localhost:0,to=99,id=default\"\n" 964#else 965 "\t\"-display none\"\n" 966#endif 967 , QEMU_ARCH_ALL) 968STEXI 969@item -display @var{type} 970@findex -display 971Select type of display to use. This option is a replacement for the 972old style -sdl/-curses/... options. Valid values for @var{type} are 973@table @option 974@item sdl 975Display video output via SDL (usually in a separate graphics 976window; see the SDL documentation for other possibilities). 977@item curses 978Display video output via curses. For graphics device models which 979support a text mode, QEMU can display this output using a 980curses/ncurses interface. Nothing is displayed when the graphics 981device is in graphical mode or if the graphics device does not support 982a text mode. Generally only the VGA device models support text mode. 983@item none 984Do not display video output. The guest will still see an emulated 985graphics card, but its output will not be displayed to the QEMU 986user. This option differs from the -nographic option in that it 987only affects what is done with video output; -nographic also changes 988the destination of the serial and parallel port data. 989@item gtk 990Display video output in a GTK window. This interface provides drop-down 991menus and other UI elements to configure and control the VM during 992runtime. 993@item vnc 994Start a VNC server on display <arg> 995@end table 996ETEXI 997 998DEF("nographic", 0, QEMU_OPTION_nographic, 999 "-nographic disable graphical output and redirect serial I/Os to console\n", 1000 QEMU_ARCH_ALL) 1001STEXI 1002@item -nographic 1003@findex -nographic 1004Normally, if QEMU is compiled with graphical window support, it displays 1005output such as guest graphics, guest console, and the QEMU monitor in a 1006window. With this option, you can totally disable graphical output so 1007that QEMU is a simple command line application. The emulated serial port 1008is redirected on the console and muxed with the monitor (unless 1009redirected elsewhere explicitly). Therefore, you can still use QEMU to 1010debug a Linux kernel with a serial console. Use @key{C-a h} for help on 1011switching between the console and monitor. 1012ETEXI 1013 1014DEF("curses", 0, QEMU_OPTION_curses, 1015 "-curses shorthand for -display curses\n", 1016 QEMU_ARCH_ALL) 1017STEXI 1018@item -curses 1019@findex -curses 1020Normally, if QEMU is compiled with graphical window support, it displays 1021output such as guest graphics, guest console, and the QEMU monitor in a 1022window. With this option, QEMU can display the VGA output when in text 1023mode using a curses/ncurses interface. Nothing is displayed in graphical 1024mode. 1025ETEXI 1026 1027DEF("no-frame", 0, QEMU_OPTION_no_frame, 1028 "-no-frame open SDL window without a frame and window decorations\n", 1029 QEMU_ARCH_ALL) 1030STEXI 1031@item -no-frame 1032@findex -no-frame 1033Do not use decorations for SDL windows and start them using the whole 1034available screen space. This makes the using QEMU in a dedicated desktop 1035workspace more convenient. 1036ETEXI 1037 1038DEF("alt-grab", 0, QEMU_OPTION_alt_grab, 1039 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n", 1040 QEMU_ARCH_ALL) 1041STEXI 1042@item -alt-grab 1043@findex -alt-grab 1044Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also 1045affects the special keys (for fullscreen, monitor-mode switching, etc). 1046ETEXI 1047 1048DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab, 1049 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n", 1050 QEMU_ARCH_ALL) 1051STEXI 1052@item -ctrl-grab 1053@findex -ctrl-grab 1054Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also 1055affects the special keys (for fullscreen, monitor-mode switching, etc). 1056ETEXI 1057 1058DEF("no-quit", 0, QEMU_OPTION_no_quit, 1059 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL) 1060STEXI 1061@item -no-quit 1062@findex -no-quit 1063Disable SDL window close capability. 1064ETEXI 1065 1066DEF("sdl", 0, QEMU_OPTION_sdl, 1067 "-sdl shorthand for -display sdl\n", QEMU_ARCH_ALL) 1068STEXI 1069@item -sdl 1070@findex -sdl 1071Enable SDL. 1072ETEXI 1073 1074DEF("spice", HAS_ARG, QEMU_OPTION_spice, 1075 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n" 1076 " [,x509-key-file=<file>][,x509-key-password=<file>]\n" 1077 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n" 1078 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n" 1079 " [,tls-ciphers=<list>]\n" 1080 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n" 1081 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n" 1082 " [,sasl][,password=<secret>][,disable-ticketing]\n" 1083 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n" 1084 " [,jpeg-wan-compression=[auto|never|always]]\n" 1085 " [,zlib-glz-wan-compression=[auto|never|always]]\n" 1086 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n" 1087 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n" 1088 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n" 1089 " [,gl=[on|off]][,rendernode=<file>]\n" 1090 " enable spice\n" 1091 " at least one of {port, tls-port} is mandatory\n", 1092 QEMU_ARCH_ALL) 1093STEXI 1094@item -spice @var{option}[,@var{option}[,...]] 1095@findex -spice 1096Enable the spice remote desktop protocol. Valid options are 1097 1098@table @option 1099 1100@item port=<nr> 1101Set the TCP port spice is listening on for plaintext channels. 1102 1103@item addr=<addr> 1104Set the IP address spice is listening on. Default is any address. 1105 1106@item ipv4 1107@itemx ipv6 1108@itemx unix 1109Force using the specified IP version. 1110 1111@item password=<secret> 1112Set the password you need to authenticate. 1113 1114@item sasl 1115Require that the client use SASL to authenticate with the spice. 1116The exact choice of authentication method used is controlled from the 1117system / user's SASL configuration file for the 'qemu' service. This 1118is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1119unprivileged user, an environment variable SASL_CONF_PATH can be used 1120to make it search alternate locations for the service config. 1121While some SASL auth methods can also provide data encryption (eg GSSAPI), 1122it is recommended that SASL always be combined with the 'tls' and 1123'x509' settings to enable use of SSL and server certificates. This 1124ensures a data encryption preventing compromise of authentication 1125credentials. 1126 1127@item disable-ticketing 1128Allow client connects without authentication. 1129 1130@item disable-copy-paste 1131Disable copy paste between the client and the guest. 1132 1133@item disable-agent-file-xfer 1134Disable spice-vdagent based file-xfer between the client and the guest. 1135 1136@item tls-port=<nr> 1137Set the TCP port spice is listening on for encrypted channels. 1138 1139@item x509-dir=<dir> 1140Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir 1141 1142@item x509-key-file=<file> 1143@itemx x509-key-password=<file> 1144@itemx x509-cert-file=<file> 1145@itemx x509-cacert-file=<file> 1146@itemx x509-dh-key-file=<file> 1147The x509 file names can also be configured individually. 1148 1149@item tls-ciphers=<list> 1150Specify which ciphers to use. 1151 1152@item tls-channel=[main|display|cursor|inputs|record|playback] 1153@itemx plaintext-channel=[main|display|cursor|inputs|record|playback] 1154Force specific channel to be used with or without TLS encryption. The 1155options can be specified multiple times to configure multiple 1156channels. The special name "default" can be used to set the default 1157mode. For channels which are not explicitly forced into one mode the 1158spice client is allowed to pick tls/plaintext as he pleases. 1159 1160@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off] 1161Configure image compression (lossless). 1162Default is auto_glz. 1163 1164@item jpeg-wan-compression=[auto|never|always] 1165@itemx zlib-glz-wan-compression=[auto|never|always] 1166Configure wan image compression (lossy for slow links). 1167Default is auto. 1168 1169@item streaming-video=[off|all|filter] 1170Configure video stream detection. Default is off. 1171 1172@item agent-mouse=[on|off] 1173Enable/disable passing mouse events via vdagent. Default is on. 1174 1175@item playback-compression=[on|off] 1176Enable/disable audio stream compression (using celt 0.5.1). Default is on. 1177 1178@item seamless-migration=[on|off] 1179Enable/disable spice seamless migration. Default is off. 1180 1181@item gl=[on|off] 1182Enable/disable OpenGL context. Default is off. 1183 1184@item rendernode=<file> 1185DRM render node for OpenGL rendering. If not specified, it will pick 1186the first available. (Since 2.9) 1187 1188@end table 1189ETEXI 1190 1191DEF("portrait", 0, QEMU_OPTION_portrait, 1192 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n", 1193 QEMU_ARCH_ALL) 1194STEXI 1195@item -portrait 1196@findex -portrait 1197Rotate graphical output 90 deg left (only PXA LCD). 1198ETEXI 1199 1200DEF("rotate", HAS_ARG, QEMU_OPTION_rotate, 1201 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n", 1202 QEMU_ARCH_ALL) 1203STEXI 1204@item -rotate @var{deg} 1205@findex -rotate 1206Rotate graphical output some deg left (only PXA LCD). 1207ETEXI 1208 1209DEF("vga", HAS_ARG, QEMU_OPTION_vga, 1210 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n" 1211 " select video card type\n", QEMU_ARCH_ALL) 1212STEXI 1213@item -vga @var{type} 1214@findex -vga 1215Select type of VGA card to emulate. Valid values for @var{type} are 1216@table @option 1217@item cirrus 1218Cirrus Logic GD5446 Video card. All Windows versions starting from 1219Windows 95 should recognize and use this graphic card. For optimal 1220performances, use 16 bit color depth in the guest and the host OS. 1221(This card was the default before QEMU 2.2) 1222@item std 1223Standard VGA card with Bochs VBE extensions. If your guest OS 1224supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want 1225to use high resolution modes (>= 1280x1024x16) then you should use 1226this option. (This card is the default since QEMU 2.2) 1227@item vmware 1228VMWare SVGA-II compatible adapter. Use it if you have sufficiently 1229recent XFree86/XOrg server or Windows guest with a driver for this 1230card. 1231@item qxl 1232QXL paravirtual graphic card. It is VGA compatible (including VESA 12332.0 VBE support). Works best with qxl guest drivers installed though. 1234Recommended choice when using the spice protocol. 1235@item tcx 1236(sun4m only) Sun TCX framebuffer. This is the default framebuffer for 1237sun4m machines and offers both 8-bit and 24-bit colour depths at a 1238fixed resolution of 1024x768. 1239@item cg3 1240(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer 1241for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP) 1242resolutions aimed at people wishing to run older Solaris versions. 1243@item virtio 1244Virtio VGA card. 1245@item none 1246Disable VGA card. 1247@end table 1248ETEXI 1249 1250DEF("full-screen", 0, QEMU_OPTION_full_screen, 1251 "-full-screen start in full screen\n", QEMU_ARCH_ALL) 1252STEXI 1253@item -full-screen 1254@findex -full-screen 1255Start in full screen. 1256ETEXI 1257 1258DEF("g", 1, QEMU_OPTION_g , 1259 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n", 1260 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 1261STEXI 1262@item -g @var{width}x@var{height}[x@var{depth}] 1263@findex -g 1264Set the initial graphical resolution and depth (PPC, SPARC only). 1265ETEXI 1266 1267DEF("vnc", HAS_ARG, QEMU_OPTION_vnc , 1268 "-vnc <display> shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL) 1269STEXI 1270@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]] 1271@findex -vnc 1272Normally, if QEMU is compiled with graphical window support, it displays 1273output such as guest graphics, guest console, and the QEMU monitor in a 1274window. With this option, you can have QEMU listen on VNC display 1275@var{display} and redirect the VGA display over the VNC session. It is 1276very useful to enable the usb tablet device when using this option 1277(option @option{-usbdevice tablet}). When using the VNC display, you 1278must use the @option{-k} parameter to set the keyboard layout if you are 1279not using en-us. Valid syntax for the @var{display} is 1280 1281@table @option 1282 1283@item to=@var{L} 1284 1285With this option, QEMU will try next available VNC @var{display}s, until the 1286number @var{L}, if the origianlly defined "-vnc @var{display}" is not 1287available, e.g. port 5900+@var{display} is already used by another 1288application. By default, to=0. 1289 1290@item @var{host}:@var{d} 1291 1292TCP connections will only be allowed from @var{host} on display @var{d}. 1293By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can 1294be omitted in which case the server will accept connections from any host. 1295 1296@item unix:@var{path} 1297 1298Connections will be allowed over UNIX domain sockets where @var{path} is the 1299location of a unix socket to listen for connections on. 1300 1301@item none 1302 1303VNC is initialized but not started. The monitor @code{change} command 1304can be used to later start the VNC server. 1305 1306@end table 1307 1308Following the @var{display} value there may be one or more @var{option} flags 1309separated by commas. Valid options are 1310 1311@table @option 1312 1313@item reverse 1314 1315Connect to a listening VNC client via a ``reverse'' connection. The 1316client is specified by the @var{display}. For reverse network 1317connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument 1318is a TCP port number, not a display number. 1319 1320@item websocket 1321 1322Opens an additional TCP listening port dedicated to VNC Websocket connections. 1323If a bare @var{websocket} option is given, the Websocket port is 13245700+@var{display}. An alternative port can be specified with the 1325syntax @code{websocket}=@var{port}. 1326 1327If @var{host} is specified connections will only be allowed from this host. 1328It is possible to control the websocket listen address independently, using 1329the syntax @code{websocket}=@var{host}:@var{port}. 1330 1331If no TLS credentials are provided, the websocket connection runs in 1332unencrypted mode. If TLS credentials are provided, the websocket connection 1333requires encrypted client connections. 1334 1335@item password 1336 1337Require that password based authentication is used for client connections. 1338 1339The password must be set separately using the @code{set_password} command in 1340the @ref{pcsys_monitor}. The syntax to change your password is: 1341@code{set_password <protocol> <password>} where <protocol> could be either 1342"vnc" or "spice". 1343 1344If you would like to change <protocol> password expiration, you should use 1345@code{expire_password <protocol> <expiration-time>} where expiration time could 1346be one of the following options: now, never, +seconds or UNIX time of 1347expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800 1348to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this 1349date and time). 1350 1351You can also use keywords "now" or "never" for the expiration time to 1352allow <protocol> password to expire immediately or never expire. 1353 1354@item tls-creds=@var{ID} 1355 1356Provides the ID of a set of TLS credentials to use to secure the 1357VNC server. They will apply to both the normal VNC server socket 1358and the websocket socket (if enabled). Setting TLS credentials 1359will cause the VNC server socket to enable the VeNCrypt auth 1360mechanism. The credentials should have been previously created 1361using the @option{-object tls-creds} argument. 1362 1363The @option{tls-creds} parameter obsoletes the @option{tls}, 1364@option{x509}, and @option{x509verify} options, and as such 1365it is not permitted to set both new and old type options at 1366the same time. 1367 1368@item tls 1369 1370Require that client use TLS when communicating with the VNC server. This 1371uses anonymous TLS credentials so is susceptible to a man-in-the-middle 1372attack. It is recommended that this option be combined with either the 1373@option{x509} or @option{x509verify} options. 1374 1375This option is now deprecated in favor of using the @option{tls-creds} 1376argument. 1377 1378@item x509=@var{/path/to/certificate/dir} 1379 1380Valid if @option{tls} is specified. Require that x509 credentials are used 1381for negotiating the TLS session. The server will send its x509 certificate 1382to the client. It is recommended that a password be set on the VNC server 1383to provide authentication of the client when this is used. The path following 1384this option specifies where the x509 certificates are to be loaded from. 1385See the @ref{vnc_security} section for details on generating certificates. 1386 1387This option is now deprecated in favour of using the @option{tls-creds} 1388argument. 1389 1390@item x509verify=@var{/path/to/certificate/dir} 1391 1392Valid if @option{tls} is specified. Require that x509 credentials are used 1393for negotiating the TLS session. The server will send its x509 certificate 1394to the client, and request that the client send its own x509 certificate. 1395The server will validate the client's certificate against the CA certificate, 1396and reject clients when validation fails. If the certificate authority is 1397trusted, this is a sufficient authentication mechanism. You may still wish 1398to set a password on the VNC server as a second authentication layer. The 1399path following this option specifies where the x509 certificates are to 1400be loaded from. See the @ref{vnc_security} section for details on generating 1401certificates. 1402 1403This option is now deprecated in favour of using the @option{tls-creds} 1404argument. 1405 1406@item sasl 1407 1408Require that the client use SASL to authenticate with the VNC server. 1409The exact choice of authentication method used is controlled from the 1410system / user's SASL configuration file for the 'qemu' service. This 1411is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1412unprivileged user, an environment variable SASL_CONF_PATH can be used 1413to make it search alternate locations for the service config. 1414While some SASL auth methods can also provide data encryption (eg GSSAPI), 1415it is recommended that SASL always be combined with the 'tls' and 1416'x509' settings to enable use of SSL and server certificates. This 1417ensures a data encryption preventing compromise of authentication 1418credentials. See the @ref{vnc_security} section for details on using 1419SASL authentication. 1420 1421@item acl 1422 1423Turn on access control lists for checking of the x509 client certificate 1424and SASL party. For x509 certs, the ACL check is made against the 1425certificate's distinguished name. This is something that looks like 1426@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is 1427made against the username, which depending on the SASL plugin, may 1428include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}. 1429When the @option{acl} flag is set, the initial access list will be 1430empty, with a @code{deny} policy. Thus no one will be allowed to 1431use the VNC server until the ACLs have been loaded. This can be 1432achieved using the @code{acl} monitor command. 1433 1434@item lossy 1435 1436Enable lossy compression methods (gradient, JPEG, ...). If this 1437option is set, VNC client may receive lossy framebuffer updates 1438depending on its encoding settings. Enabling this option can save 1439a lot of bandwidth at the expense of quality. 1440 1441@item non-adaptive 1442 1443Disable adaptive encodings. Adaptive encodings are enabled by default. 1444An adaptive encoding will try to detect frequently updated screen regions, 1445and send updates in these regions using a lossy encoding (like JPEG). 1446This can be really helpful to save bandwidth when playing videos. Disabling 1447adaptive encodings restores the original static behavior of encodings 1448like Tight. 1449 1450@item share=[allow-exclusive|force-shared|ignore] 1451 1452Set display sharing policy. 'allow-exclusive' allows clients to ask 1453for exclusive access. As suggested by the rfb spec this is 1454implemented by dropping other connections. Connecting multiple 1455clients in parallel requires all clients asking for a shared session 1456(vncviewer: -shared switch). This is the default. 'force-shared' 1457disables exclusive client access. Useful for shared desktop sessions, 1458where you don't want someone forgetting specify -shared disconnect 1459everybody else. 'ignore' completely ignores the shared flag and 1460allows everybody connect unconditionally. Doesn't conform to the rfb 1461spec but is traditional QEMU behavior. 1462 1463@item key-delay-ms 1464 1465Set keyboard delay, for key down and key up events, in milliseconds. 1466Default is 1. Keyboards are low-bandwidth devices, so this slowdown 1467can help the device and guest to keep up and not lose events in case 1468events are arriving in bulk. Possible causes for the latter are flaky 1469network connections, or scripts for automated testing. 1470 1471@end table 1472ETEXI 1473 1474STEXI 1475@end table 1476ETEXI 1477ARCHHEADING(, QEMU_ARCH_I386) 1478 1479ARCHHEADING(i386 target only, QEMU_ARCH_I386) 1480STEXI 1481@table @option 1482ETEXI 1483 1484DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack, 1485 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n", 1486 QEMU_ARCH_I386) 1487STEXI 1488@item -win2k-hack 1489@findex -win2k-hack 1490Use it when installing Windows 2000 to avoid a disk full bug. After 1491Windows 2000 is installed, you no longer need this option (this option 1492slows down the IDE transfers). 1493ETEXI 1494 1495HXCOMM Deprecated by -rtc 1496DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386) 1497 1498DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk, 1499 "-no-fd-bootchk disable boot signature checking for floppy disks\n", 1500 QEMU_ARCH_I386) 1501STEXI 1502@item -no-fd-bootchk 1503@findex -no-fd-bootchk 1504Disable boot signature checking for floppy disks in BIOS. May 1505be needed to boot from old floppy disks. 1506ETEXI 1507 1508DEF("no-acpi", 0, QEMU_OPTION_no_acpi, 1509 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1510STEXI 1511@item -no-acpi 1512@findex -no-acpi 1513Disable ACPI (Advanced Configuration and Power Interface) support. Use 1514it if your guest OS complains about ACPI problems (PC target machine 1515only). 1516ETEXI 1517 1518DEF("no-hpet", 0, QEMU_OPTION_no_hpet, 1519 "-no-hpet disable HPET\n", QEMU_ARCH_I386) 1520STEXI 1521@item -no-hpet 1522@findex -no-hpet 1523Disable HPET support. 1524ETEXI 1525 1526DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable, 1527 "-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" 1528 " ACPI table description\n", QEMU_ARCH_I386) 1529STEXI 1530@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}]...] 1531@findex -acpitable 1532Add ACPI table with specified header fields and context from specified files. 1533For file=, take whole ACPI table from the specified files, including all 1534ACPI headers (possible overridden by other options). 1535For data=, only data 1536portion of the table is used, all header information is specified in the 1537command line. 1538If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id 1539fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order 1540to ensure the field matches required by the Microsoft SLIC spec and the ACPI 1541spec. 1542ETEXI 1543 1544DEF("smbios", HAS_ARG, QEMU_OPTION_smbios, 1545 "-smbios file=binary\n" 1546 " load SMBIOS entry from binary file\n" 1547 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n" 1548 " [,uefi=on|off]\n" 1549 " specify SMBIOS type 0 fields\n" 1550 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1551 " [,uuid=uuid][,sku=str][,family=str]\n" 1552 " specify SMBIOS type 1 fields\n" 1553 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1554 " [,asset=str][,location=str]\n" 1555 " specify SMBIOS type 2 fields\n" 1556 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n" 1557 " [,sku=str]\n" 1558 " specify SMBIOS type 3 fields\n" 1559 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n" 1560 " [,asset=str][,part=str]\n" 1561 " specify SMBIOS type 4 fields\n" 1562 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n" 1563 " [,asset=str][,part=str][,speed=%d]\n" 1564 " specify SMBIOS type 17 fields\n", 1565 QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1566STEXI 1567@item -smbios file=@var{binary} 1568@findex -smbios 1569Load SMBIOS entry from binary file. 1570 1571@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off] 1572Specify SMBIOS type 0 fields 1573 1574@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}] 1575Specify SMBIOS type 1 fields 1576 1577@item -smbios type=2[,manufacturer=@var{str}][,product=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,location=@var{str}][,family=@var{str}] 1578Specify SMBIOS type 2 fields 1579 1580@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}] 1581Specify SMBIOS type 3 fields 1582 1583@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}] 1584Specify SMBIOS type 4 fields 1585 1586@item -smbios type=17[,loc_pfx=@var{str}][,bank=@var{str}][,manufacturer=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}][,speed=@var{%d}] 1587Specify SMBIOS type 17 fields 1588ETEXI 1589 1590STEXI 1591@end table 1592ETEXI 1593DEFHEADING() 1594 1595DEFHEADING(Network options) 1596STEXI 1597@table @option 1598ETEXI 1599 1600HXCOMM Legacy slirp options (now moved to -net user): 1601#ifdef CONFIG_SLIRP 1602DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL) 1603DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL) 1604DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL) 1605#ifndef _WIN32 1606DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL) 1607#endif 1608#endif 1609 1610DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, 1611#ifdef CONFIG_SLIRP 1612 "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n" 1613 " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n" 1614 " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n" 1615 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,tftp=dir]\n" 1616 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]" 1617#ifndef _WIN32 1618 "[,smb=dir[,smbserver=addr]]\n" 1619#endif 1620 " configure a user mode network backend with ID 'str',\n" 1621 " its DHCP server and optional services\n" 1622#endif 1623#ifdef _WIN32 1624 "-netdev tap,id=str,ifname=name\n" 1625 " configure a host TAP network backend with ID 'str'\n" 1626#else 1627 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n" 1628 " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n" 1629 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n" 1630 " [,poll-us=n]\n" 1631 " configure a host TAP network backend with ID 'str'\n" 1632 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 1633 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n" 1634 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n" 1635 " to deconfigure it\n" 1636 " use '[down]script=no' to disable script execution\n" 1637 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n" 1638 " configure it\n" 1639 " use 'fd=h' to connect to an already opened TAP interface\n" 1640 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n" 1641 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n" 1642 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n" 1643 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n" 1644 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" 1645 " use vhost=on to enable experimental in kernel accelerator\n" 1646 " (only has effect for virtio guests which use MSIX)\n" 1647 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n" 1648 " use 'vhostfd=h' to connect to an already opened vhost net device\n" 1649 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n" 1650 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n" 1651 " use 'poll-us=n' to speciy the maximum number of microseconds that could be\n" 1652 " spent on busy polling for vhost net\n" 1653 "-netdev bridge,id=str[,br=bridge][,helper=helper]\n" 1654 " configure a host TAP network backend with ID 'str' that is\n" 1655 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 1656 " using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n" 1657#endif 1658#ifdef __linux__ 1659 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n" 1660 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n" 1661 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n" 1662 " [,rxcookie=rxcookie][,offset=offset]\n" 1663 " configure a network backend with ID 'str' connected to\n" 1664 " an Ethernet over L2TPv3 pseudowire.\n" 1665 " Linux kernel 3.3+ as well as most routers can talk\n" 1666 " L2TPv3. This transport allows connecting a VM to a VM,\n" 1667 " VM to a router and even VM to Host. It is a nearly-universal\n" 1668 " standard (RFC3391). Note - this implementation uses static\n" 1669 " pre-configured tunnels (same as the Linux kernel).\n" 1670 " use 'src=' to specify source address\n" 1671 " use 'dst=' to specify destination address\n" 1672 " use 'udp=on' to specify udp encapsulation\n" 1673 " use 'srcport=' to specify source udp port\n" 1674 " use 'dstport=' to specify destination udp port\n" 1675 " use 'ipv6=on' to force v6\n" 1676 " L2TPv3 uses cookies to prevent misconfiguration as\n" 1677 " well as a weak security measure\n" 1678 " use 'rxcookie=0x012345678' to specify a rxcookie\n" 1679 " use 'txcookie=0x012345678' to specify a txcookie\n" 1680 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n" 1681 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n" 1682 " use 'pincounter=on' to work around broken counter handling in peer\n" 1683 " use 'offset=X' to add an extra offset between header and data\n" 1684#endif 1685 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n" 1686 " configure a network backend to connect to another network\n" 1687 " using a socket connection\n" 1688 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n" 1689 " configure a network backend to connect to a multicast maddr and port\n" 1690 " use 'localaddr=addr' to specify the host address to send packets from\n" 1691 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n" 1692 " configure a network backend to connect to another network\n" 1693 " using an UDP tunnel\n" 1694#ifdef CONFIG_VDE 1695 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n" 1696 " configure a network backend to connect to port 'n' of a vde switch\n" 1697 " running on host and listening for incoming connections on 'socketpath'.\n" 1698 " Use group 'groupname' and mode 'octalmode' to change default\n" 1699 " ownership and permissions for communication port.\n" 1700#endif 1701#ifdef CONFIG_NETMAP 1702 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n" 1703 " attach to the existing netmap-enabled network interface 'name', or to a\n" 1704 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n" 1705 " netmap device, defaults to '/dev/netmap')\n" 1706#endif 1707 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n" 1708 " configure a vhost-user network, backed by a chardev 'dev'\n" 1709 "-netdev hubport,id=str,hubid=n\n" 1710 " configure a hub port on QEMU VLAN 'n'\n", QEMU_ARCH_ALL) 1711DEF("net", HAS_ARG, QEMU_OPTION_net, 1712 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n" 1713 " old way to create a new NIC and connect it to VLAN 'n'\n" 1714 " (use the '-device devtype,netdev=str' option if possible instead)\n" 1715 "-net dump[,vlan=n][,file=f][,len=n]\n" 1716 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n" 1717 "-net none use it alone to have zero network devices. If no -net option\n" 1718 " is provided, the default is '-net nic -net user'\n" 1719 "-net [" 1720#ifdef CONFIG_SLIRP 1721 "user|" 1722#endif 1723 "tap|" 1724 "bridge|" 1725#ifdef CONFIG_VDE 1726 "vde|" 1727#endif 1728#ifdef CONFIG_NETMAP 1729 "netmap|" 1730#endif 1731 "socket][,vlan=n][,option][,option][,...]\n" 1732 " old way to initialize a host network interface\n" 1733 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL) 1734STEXI 1735@item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}] 1736@findex -net 1737Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n} 1738= 0 is the default). The NIC is an e1000 by default on the PC 1739target. Optionally, the MAC address can be changed to @var{mac}, the 1740device address set to @var{addr} (PCI cards only), 1741and a @var{name} can be assigned for use in monitor commands. 1742Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors 1743that the card should have; this option currently only affects virtio cards; set 1744@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single 1745NIC is created. QEMU can emulate several different models of network card. 1746Valid values for @var{type} are 1747@code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er}, 1748@code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139}, 1749@code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}. 1750Not all devices are supported on all targets. Use @code{-net nic,model=help} 1751for a list of available devices for your target. 1752 1753@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...] 1754@findex -netdev 1755@item -net user[,@var{option}][,@var{option}][,...] 1756Use the user mode network stack which requires no administrator 1757privilege to run. Valid options are: 1758 1759@table @option 1760@item vlan=@var{n} 1761Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default). 1762 1763@item id=@var{id} 1764@itemx name=@var{name} 1765Assign symbolic name for use in monitor commands. 1766 1767@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must 1768be enabled. If neither is specified both protocols are enabled. 1769 1770@item net=@var{addr}[/@var{mask}] 1771Set IP network address the guest will see. Optionally specify the netmask, 1772either in the form a.b.c.d or as number of valid top-most bits. Default is 177310.0.2.0/24. 1774 1775@item host=@var{addr} 1776Specify the guest-visible address of the host. Default is the 2nd IP in the 1777guest network, i.e. x.x.x.2. 1778 1779@item ipv6-net=@var{addr}[/@var{int}] 1780Set IPv6 network address the guest will see (default is fec0::/64). The 1781network prefix is given in the usual hexadecimal IPv6 address 1782notation. The prefix size is optional, and is given as the number of 1783valid top-most bits (default is 64). 1784 1785@item ipv6-host=@var{addr} 1786Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in 1787the guest network, i.e. xxxx::2. 1788 1789@item restrict=on|off 1790If this option is enabled, the guest will be isolated, i.e. it will not be 1791able to contact the host and no guest IP packets will be routed over the host 1792to the outside. This option does not affect any explicitly set forwarding rules. 1793 1794@item hostname=@var{name} 1795Specifies the client hostname reported by the built-in DHCP server. 1796 1797@item dhcpstart=@var{addr} 1798Specify the first of the 16 IPs the built-in DHCP server can assign. Default 1799is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31. 1800 1801@item dns=@var{addr} 1802Specify the guest-visible address of the virtual nameserver. The address must 1803be different from the host address. Default is the 3rd IP in the guest network, 1804i.e. x.x.x.3. 1805 1806@item ipv6-dns=@var{addr} 1807Specify the guest-visible address of the IPv6 virtual nameserver. The address 1808must be different from the host address. Default is the 3rd IP in the guest 1809network, i.e. xxxx::3. 1810 1811@item dnssearch=@var{domain} 1812Provides an entry for the domain-search list sent by the built-in 1813DHCP server. More than one domain suffix can be transmitted by specifying 1814this option multiple times. If supported, this will cause the guest to 1815automatically try to append the given domain suffix(es) in case a domain name 1816can not be resolved. 1817 1818Example: 1819@example 1820qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...] 1821@end example 1822 1823@item tftp=@var{dir} 1824When using the user mode network stack, activate a built-in TFTP 1825server. The files in @var{dir} will be exposed as the root of a TFTP server. 1826The TFTP client on the guest must be configured in binary mode (use the command 1827@code{bin} of the Unix TFTP client). 1828 1829@item bootfile=@var{file} 1830When using the user mode network stack, broadcast @var{file} as the BOOTP 1831filename. In conjunction with @option{tftp}, this can be used to network boot 1832a guest from a local directory. 1833 1834Example (using pxelinux): 1835@example 1836qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0 1837@end example 1838 1839@item smb=@var{dir}[,smbserver=@var{addr}] 1840When using the user mode network stack, activate a built-in SMB 1841server so that Windows OSes can access to the host files in @file{@var{dir}} 1842transparently. The IP address of the SMB server can be set to @var{addr}. By 1843default the 4th IP in the guest network is used, i.e. x.x.x.4. 1844 1845In the guest Windows OS, the line: 1846@example 184710.0.2.4 smbserver 1848@end example 1849must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me) 1850or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000). 1851 1852Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}. 1853 1854Note that a SAMBA server must be installed on the host OS. 1855QEMU was tested successfully with smbd versions from Red Hat 9, 1856Fedora Core 3 and OpenSUSE 11.x. 1857 1858@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport} 1859Redirect incoming TCP or UDP connections to the host port @var{hostport} to 1860the guest IP address @var{guestaddr} on guest port @var{guestport}. If 1861@var{guestaddr} is not specified, its value is x.x.x.15 (default first address 1862given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can 1863be bound to a specific host interface. If no connection type is set, TCP is 1864used. This option can be given multiple times. 1865 1866For example, to redirect host X11 connection from screen 1 to guest 1867screen 0, use the following: 1868 1869@example 1870# on the host 1871qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...] 1872# this host xterm should open in the guest X11 server 1873xterm -display :1 1874@end example 1875 1876To redirect telnet connections from host port 5555 to telnet port on 1877the guest, use the following: 1878 1879@example 1880# on the host 1881qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...] 1882telnet localhost 5555 1883@end example 1884 1885Then when you use on the host @code{telnet localhost 5555}, you 1886connect to the guest telnet server. 1887 1888@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev} 1889@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command} 1890Forward guest TCP connections to the IP address @var{server} on port @var{port} 1891to the character device @var{dev} or to a program executed by @var{cmd:command} 1892which gets spawned for each connection. This option can be given multiple times. 1893 1894You can either use a chardev directly and have that one used throughout QEMU's 1895lifetime, like in the following example: 1896 1897@example 1898# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever 1899# the guest accesses it 1900qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...] 1901@end example 1902 1903Or you can execute a command on every TCP connection established by the guest, 1904so that QEMU behaves similar to an inetd process for that virtual server: 1905 1906@example 1907# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 1908# and connect the TCP stream to its stdin/stdout 1909qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321' 1910@end example 1911 1912@end table 1913 1914Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still 1915processed and applied to -net user. Mixing them with the new configuration 1916syntax gives undefined results. Their use for new applications is discouraged 1917as they will be removed from future versions. 1918 1919@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}] 1920@itemx -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}] 1921Connect the host TAP network interface @var{name} to VLAN @var{n}. 1922 1923Use the network script @var{file} to configure it and the network script 1924@var{dfile} to deconfigure it. If @var{name} is not provided, the OS 1925automatically provides one. The default network configure script is 1926@file{/etc/qemu-ifup} and the default network deconfigure script is 1927@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no} 1928to disable script execution. 1929 1930If running QEMU as an unprivileged user, use the network helper 1931@var{helper} to configure the TAP interface and attach it to the bridge. 1932The default network helper executable is @file{/path/to/qemu-bridge-helper} 1933and the default bridge device is @file{br0}. 1934 1935@option{fd}=@var{h} can be used to specify the handle of an already 1936opened host TAP interface. 1937 1938Examples: 1939 1940@example 1941#launch a QEMU instance with the default network script 1942qemu-system-i386 linux.img -net nic -net tap 1943@end example 1944 1945@example 1946#launch a QEMU instance with two NICs, each one connected 1947#to a TAP device 1948qemu-system-i386 linux.img \ 1949 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \ 1950 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1 1951@end example 1952 1953@example 1954#launch a QEMU instance with the default network helper to 1955#connect a TAP device to bridge br0 1956qemu-system-i386 linux.img \ 1957 -net nic -net tap,"helper=/path/to/qemu-bridge-helper" 1958@end example 1959 1960@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}] 1961@itemx -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}] 1962Connect a host TAP network interface to a host bridge device. 1963 1964Use the network helper @var{helper} to configure the TAP interface and 1965attach it to the bridge. The default network helper executable is 1966@file{/path/to/qemu-bridge-helper} and the default bridge 1967device is @file{br0}. 1968 1969Examples: 1970 1971@example 1972#launch a QEMU instance with the default network helper to 1973#connect a TAP device to bridge br0 1974qemu-system-i386 linux.img -net bridge -net nic,model=virtio 1975@end example 1976 1977@example 1978#launch a QEMU instance with the default network helper to 1979#connect a TAP device to bridge qemubr0 1980qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio 1981@end example 1982 1983@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 1984@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 1985 1986Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual 1987machine using a TCP socket connection. If @option{listen} is 1988specified, QEMU waits for incoming connections on @var{port} 1989(@var{host} is optional). @option{connect} is used to connect to 1990another QEMU instance using the @option{listen} option. @option{fd}=@var{h} 1991specifies an already opened TCP socket. 1992 1993Example: 1994@example 1995# launch a first QEMU instance 1996qemu-system-i386 linux.img \ 1997 -net nic,macaddr=52:54:00:12:34:56 \ 1998 -net socket,listen=:1234 1999# connect the VLAN 0 of this instance to the VLAN 0 2000# of the first instance 2001qemu-system-i386 linux.img \ 2002 -net nic,macaddr=52:54:00:12:34:57 \ 2003 -net socket,connect=127.0.0.1:1234 2004@end example 2005 2006@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 2007@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 2008 2009Create a VLAN @var{n} shared with another QEMU virtual 2010machines using a UDP multicast socket, effectively making a bus for 2011every QEMU with same multicast address @var{maddr} and @var{port}. 2012NOTES: 2013@enumerate 2014@item 2015Several QEMU can be running on different hosts and share same bus (assuming 2016correct multicast setup for these hosts). 2017@item 2018mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see 2019@url{http://user-mode-linux.sf.net}. 2020@item 2021Use @option{fd=h} to specify an already opened UDP multicast socket. 2022@end enumerate 2023 2024Example: 2025@example 2026# launch one QEMU instance 2027qemu-system-i386 linux.img \ 2028 -net nic,macaddr=52:54:00:12:34:56 \ 2029 -net socket,mcast=230.0.0.1:1234 2030# launch another QEMU instance on same "bus" 2031qemu-system-i386 linux.img \ 2032 -net nic,macaddr=52:54:00:12:34:57 \ 2033 -net socket,mcast=230.0.0.1:1234 2034# launch yet another QEMU instance on same "bus" 2035qemu-system-i386 linux.img \ 2036 -net nic,macaddr=52:54:00:12:34:58 \ 2037 -net socket,mcast=230.0.0.1:1234 2038@end example 2039 2040Example (User Mode Linux compat.): 2041@example 2042# launch QEMU instance (note mcast address selected 2043# is UML's default) 2044qemu-system-i386 linux.img \ 2045 -net nic,macaddr=52:54:00:12:34:56 \ 2046 -net socket,mcast=239.192.168.1:1102 2047# launch UML 2048/path/to/linux ubd0=/path/to/root_fs eth0=mcast 2049@end example 2050 2051Example (send packets from host's 1.2.3.4): 2052@example 2053qemu-system-i386 linux.img \ 2054 -net nic,macaddr=52:54:00:12:34:56 \ 2055 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4 2056@end example 2057 2058@item -netdev l2tpv3,id=@var{id},src=@var{srcaddr},dst=@var{dstaddr}[,srcport=@var{srcport}][,dstport=@var{dstport}],txsession=@var{txsession}[,rxsession=@var{rxsession}][,ipv6][,udp][,cookie64][,counter][,pincounter][,txcookie=@var{txcookie}][,rxcookie=@var{rxcookie}][,offset=@var{offset}] 2059@itemx -net l2tpv3[,vlan=@var{n}][,name=@var{name}],src=@var{srcaddr},dst=@var{dstaddr}[,srcport=@var{srcport}][,dstport=@var{dstport}],txsession=@var{txsession}[,rxsession=@var{rxsession}][,ipv6][,udp][,cookie64][,counter][,pincounter][,txcookie=@var{txcookie}][,rxcookie=@var{rxcookie}][,offset=@var{offset}] 2060Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular 2061protocol to transport Ethernet (and other Layer 2) data frames between 2062two systems. It is present in routers, firewalls and the Linux kernel 2063(from version 3.3 onwards). 2064 2065This transport allows a VM to communicate to another VM, router or firewall directly. 2066 2067@item src=@var{srcaddr} 2068 source address (mandatory) 2069@item dst=@var{dstaddr} 2070 destination address (mandatory) 2071@item udp 2072 select udp encapsulation (default is ip). 2073@item srcport=@var{srcport} 2074 source udp port. 2075@item dstport=@var{dstport} 2076 destination udp port. 2077@item ipv6 2078 force v6, otherwise defaults to v4. 2079@item rxcookie=@var{rxcookie} 2080@itemx txcookie=@var{txcookie} 2081 Cookies are a weak form of security in the l2tpv3 specification. 2082Their function is mostly to prevent misconfiguration. By default they are 32 2083bit. 2084@item cookie64 2085 Set cookie size to 64 bit instead of the default 32 2086@item counter=off 2087 Force a 'cut-down' L2TPv3 with no counter as in 2088draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00 2089@item pincounter=on 2090 Work around broken counter handling in peer. This may also help on 2091networks which have packet reorder. 2092@item offset=@var{offset} 2093 Add an extra offset between header and data 2094 2095For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan 2096on the remote Linux host 1.2.3.4: 2097@example 2098# Setup tunnel on linux host using raw ip as encapsulation 2099# on 1.2.3.4 2100ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \ 2101 encap udp udp_sport 16384 udp_dport 16384 2102ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \ 2103 0xFFFFFFFF peer_session_id 0xFFFFFFFF 2104ifconfig vmtunnel0 mtu 1500 2105ifconfig vmtunnel0 up 2106brctl addif br-lan vmtunnel0 2107 2108 2109# on 4.3.2.1 2110# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter 2111 2112qemu-system-i386 linux.img -net nic -net l2tpv3,src=4.2.3.1,dst=1.2.3.4,udp,srcport=16384,dstport=16384,rxsession=0xffffffff,txsession=0xffffffff,counter 2113 2114 2115@end example 2116 2117@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 2118@itemx -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 2119Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and 2120listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname} 2121and MODE @var{octalmode} to change default ownership and permissions for 2122communication port. This option is only available if QEMU has been compiled 2123with vde support enabled. 2124 2125Example: 2126@example 2127# launch vde switch 2128vde_switch -F -sock /tmp/myswitch 2129# launch QEMU instance 2130qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch 2131@end example 2132 2133@item -netdev hubport,id=@var{id},hubid=@var{hubid} 2134 2135Create a hub port on QEMU "vlan" @var{hubid}. 2136 2137The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single 2138netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the 2139required hub automatically. 2140 2141@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n] 2142 2143Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should 2144be a unix domain socket backed one. The vhost-user uses a specifically defined 2145protocol to pass vhost ioctl replacement messages to an application on the other 2146end of the socket. On non-MSIX guests, the feature can be forced with 2147@var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to 2148be created for multiqueue vhost-user. 2149 2150Example: 2151@example 2152qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \ 2153 -numa node,memdev=mem \ 2154 -chardev socket,id=chr0,path=/path/to/socket \ 2155 -netdev type=vhost-user,id=net0,chardev=chr0 \ 2156 -device virtio-net-pci,netdev=net0 2157@end example 2158 2159@item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}] 2160Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default). 2161At most @var{len} bytes (64k by default) per packet are stored. The file format is 2162libpcap, so it can be analyzed with tools such as tcpdump or Wireshark. 2163Note: For devices created with '-netdev', use '-object filter-dump,...' instead. 2164 2165@item -net none 2166Indicate that no network devices should be configured. It is used to 2167override the default configuration (@option{-net nic -net user}) which 2168is activated if no @option{-net} options are provided. 2169ETEXI 2170 2171STEXI 2172@end table 2173ETEXI 2174DEFHEADING() 2175 2176DEFHEADING(Character device options) 2177STEXI 2178 2179The general form of a character device option is: 2180@table @option 2181ETEXI 2182 2183DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, 2184 "-chardev help\n" 2185 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2186 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n" 2187 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n" 2188 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n" 2189 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n" 2190 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n" 2191 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" 2192 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n" 2193 " [,logfile=PATH][,logappend=on|off]\n" 2194 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2195 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n" 2196 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2197 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n" 2198 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2199 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2200#ifdef _WIN32 2201 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2202 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2203#else 2204 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2205 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n" 2206#endif 2207#ifdef CONFIG_BRLAPI 2208 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2209#endif 2210#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 2211 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) 2212 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2213 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2214#endif 2215#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) 2216 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2217 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2218#endif 2219#if defined(CONFIG_SPICE) 2220 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2221 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2222#endif 2223 , QEMU_ARCH_ALL 2224) 2225 2226STEXI 2227@item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}] 2228@findex -chardev 2229Backend is one of: 2230@option{null}, 2231@option{socket}, 2232@option{udp}, 2233@option{msmouse}, 2234@option{vc}, 2235@option{ringbuf}, 2236@option{file}, 2237@option{pipe}, 2238@option{console}, 2239@option{serial}, 2240@option{pty}, 2241@option{stdio}, 2242@option{braille}, 2243@option{tty}, 2244@option{parallel}, 2245@option{parport}, 2246@option{spicevmc}. 2247@option{spiceport}. 2248The specific backend will determine the applicable options. 2249 2250Use "-chardev help" to print all available chardev backend types. 2251 2252All devices must have an id, which can be any string up to 127 characters long. 2253It is used to uniquely identify this device in other command line directives. 2254 2255A character device may be used in multiplexing mode by multiple front-ends. 2256Specify @option{mux=on} to enable this mode. 2257A multiplexer is a "1:N" device, and here the "1" end is your specified chardev 2258backend, and the "N" end is the various parts of QEMU that can talk to a chardev. 2259If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will 2260create a multiplexer with your specified ID, and you can then configure multiple 2261front ends to use that chardev ID for their input/output. Up to four different 2262front ends can be connected to a single multiplexed chardev. (Without 2263multiplexing enabled, a chardev can only be used by a single front end.) 2264For instance you could use this to allow a single stdio chardev to be used by 2265two serial ports and the QEMU monitor: 2266 2267@example 2268-chardev stdio,mux=on,id=char0 \ 2269-mon chardev=char0,mode=readline \ 2270-serial chardev:char0 \ 2271-serial chardev:char0 2272@end example 2273 2274You can have more than one multiplexer in a system configuration; for instance 2275you could have a TCP port multiplexed between UART 0 and UART 1, and stdio 2276multiplexed between the QEMU monitor and a parallel port: 2277 2278@example 2279-chardev stdio,mux=on,id=char0 \ 2280-mon chardev=char0,mode=readline \ 2281-parallel chardev:char0 \ 2282-chardev tcp,...,mux=on,id=char1 \ 2283-serial chardev:char1 \ 2284-serial chardev:char1 2285@end example 2286 2287When you're using a multiplexed character device, some escape sequences are 2288interpreted in the input. @xref{mux_keys, Keys in the character backend 2289multiplexer}. 2290 2291Note that some other command line options may implicitly create multiplexed 2292character backends; for instance @option{-serial mon:stdio} creates a 2293multiplexed stdio backend connected to the serial port and the QEMU monitor, 2294and @option{-nographic} also multiplexes the console and the monitor to 2295stdio. 2296 2297There is currently no support for multiplexing in the other direction 2298(where a single QEMU front end takes input and output from multiple chardevs). 2299 2300Every backend supports the @option{logfile} option, which supplies the path 2301to a file to record all data transmitted via the backend. The @option{logappend} 2302option controls whether the log file will be truncated or appended to when 2303opened. 2304 2305Further options to each backend are described below. 2306 2307@item -chardev null ,id=@var{id} 2308A void device. This device will not emit any data, and will drop any data it 2309receives. The null backend does not take any options. 2310 2311@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}] [,tls-creds=@var{id}] 2312 2313Create a two-way stream socket, which can be either a TCP or a unix socket. A 2314unix socket will be created if @option{path} is specified. Behaviour is 2315undefined if TCP options are specified for a unix socket. 2316 2317@option{server} specifies that the socket shall be a listening socket. 2318 2319@option{nowait} specifies that QEMU should not block waiting for a client to 2320connect to a listening socket. 2321 2322@option{telnet} specifies that traffic on the socket should interpret telnet 2323escape sequences. 2324 2325@option{reconnect} sets the timeout for reconnecting on non-server sockets when 2326the remote end goes away. qemu will delay this many seconds and then attempt 2327to reconnect. Zero disables reconnecting, and is the default. 2328 2329@option{tls-creds} requests enablement of the TLS protocol for encryption, 2330and specifies the id of the TLS credentials to use for the handshake. The 2331credentials must be previously created with the @option{-object tls-creds} 2332argument. 2333 2334TCP and unix socket options are given below: 2335 2336@table @option 2337 2338@item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay] 2339 2340@option{host} for a listening socket specifies the local address to be bound. 2341For a connecting socket species the remote host to connect to. @option{host} is 2342optional for listening sockets. If not specified it defaults to @code{0.0.0.0}. 2343 2344@option{port} for a listening socket specifies the local port to be bound. For a 2345connecting socket specifies the port on the remote host to connect to. 2346@option{port} can be given as either a port number or a service name. 2347@option{port} is required. 2348 2349@option{to} is only relevant to listening sockets. If it is specified, and 2350@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up 2351to and including @option{to} until it succeeds. @option{to} must be specified 2352as a port number. 2353 2354@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2355If neither is specified the socket may use either protocol. 2356 2357@option{nodelay} disables the Nagle algorithm. 2358 2359@item unix options: path=@var{path} 2360 2361@option{path} specifies the local path of the unix socket. @option{path} is 2362required. 2363 2364@end table 2365 2366@item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6] 2367 2368Sends all traffic from the guest to a remote host over UDP. 2369 2370@option{host} specifies the remote host to connect to. If not specified it 2371defaults to @code{localhost}. 2372 2373@option{port} specifies the port on the remote host to connect to. @option{port} 2374is required. 2375 2376@option{localaddr} specifies the local address to bind to. If not specified it 2377defaults to @code{0.0.0.0}. 2378 2379@option{localport} specifies the local port to bind to. If not specified any 2380available local port will be used. 2381 2382@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2383If neither is specified the device may use either protocol. 2384 2385@item -chardev msmouse ,id=@var{id} 2386 2387Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not 2388take any options. 2389 2390@item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]] 2391 2392Connect to a QEMU text console. @option{vc} may optionally be given a specific 2393size. 2394 2395@option{width} and @option{height} specify the width and height respectively of 2396the console, in pixels. 2397 2398@option{cols} and @option{rows} specify that the console be sized to fit a text 2399console with the given dimensions. 2400 2401@item -chardev ringbuf ,id=@var{id} [,size=@var{size}] 2402 2403Create a ring buffer with fixed size @option{size}. 2404@var{size} must be a power of two and defaults to @code{64K}. 2405 2406@item -chardev file ,id=@var{id} ,path=@var{path} 2407 2408Log all traffic received from the guest to a file. 2409 2410@option{path} specifies the path of the file to be opened. This file will be 2411created if it does not already exist, and overwritten if it does. @option{path} 2412is required. 2413 2414@item -chardev pipe ,id=@var{id} ,path=@var{path} 2415 2416Create a two-way connection to the guest. The behaviour differs slightly between 2417Windows hosts and other hosts: 2418 2419On Windows, a single duplex pipe will be created at 2420@file{\\.pipe\@option{path}}. 2421 2422On other hosts, 2 pipes will be created called @file{@option{path}.in} and 2423@file{@option{path}.out}. Data written to @file{@option{path}.in} will be 2424received by the guest. Data written by the guest can be read from 2425@file{@option{path}.out}. QEMU will not create these fifos, and requires them to 2426be present. 2427 2428@option{path} forms part of the pipe path as described above. @option{path} is 2429required. 2430 2431@item -chardev console ,id=@var{id} 2432 2433Send traffic from the guest to QEMU's standard output. @option{console} does not 2434take any options. 2435 2436@option{console} is only available on Windows hosts. 2437 2438@item -chardev serial ,id=@var{id} ,path=@option{path} 2439 2440Send traffic from the guest to a serial device on the host. 2441 2442On Unix hosts serial will actually accept any tty device, 2443not only serial lines. 2444 2445@option{path} specifies the name of the serial device to open. 2446 2447@item -chardev pty ,id=@var{id} 2448 2449Create a new pseudo-terminal on the host and connect to it. @option{pty} does 2450not take any options. 2451 2452@option{pty} is not available on Windows hosts. 2453 2454@item -chardev stdio ,id=@var{id} [,signal=on|off] 2455Connect to standard input and standard output of the QEMU process. 2456 2457@option{signal} controls if signals are enabled on the terminal, that includes 2458exiting QEMU with the key sequence @key{Control-c}. This option is enabled by 2459default, use @option{signal=off} to disable it. 2460 2461@item -chardev braille ,id=@var{id} 2462 2463Connect to a local BrlAPI server. @option{braille} does not take any options. 2464 2465@item -chardev tty ,id=@var{id} ,path=@var{path} 2466 2467@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and 2468DragonFlyBSD hosts. It is an alias for @option{serial}. 2469 2470@option{path} specifies the path to the tty. @option{path} is required. 2471 2472@item -chardev parallel ,id=@var{id} ,path=@var{path} 2473@itemx -chardev parport ,id=@var{id} ,path=@var{path} 2474 2475@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts. 2476 2477Connect to a local parallel port. 2478 2479@option{path} specifies the path to the parallel port device. @option{path} is 2480required. 2481 2482@item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name} 2483 2484@option{spicevmc} is only available when spice support is built in. 2485 2486@option{debug} debug level for spicevmc 2487 2488@option{name} name of spice channel to connect to 2489 2490Connect to a spice virtual machine channel, such as vdiport. 2491 2492@item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name} 2493 2494@option{spiceport} is only available when spice support is built in. 2495 2496@option{debug} debug level for spicevmc 2497 2498@option{name} name of spice port to connect to 2499 2500Connect to a spice port, allowing a Spice client to handle the traffic 2501identified by a name (preferably a fqdn). 2502ETEXI 2503 2504STEXI 2505@end table 2506ETEXI 2507DEFHEADING() 2508 2509DEFHEADING(Device URL Syntax) 2510STEXI 2511 2512In addition to using normal file images for the emulated storage devices, 2513QEMU can also use networked resources such as iSCSI devices. These are 2514specified using a special URL syntax. 2515 2516@table @option 2517@item iSCSI 2518iSCSI support allows QEMU to access iSCSI resources directly and use as 2519images for the guest storage. Both disk and cdrom images are supported. 2520 2521Syntax for specifying iSCSI LUNs is 2522``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>'' 2523 2524By default qemu will use the iSCSI initiator-name 2525'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command 2526line or a configuration file. 2527 2528Since version Qemu 2.4 it is possible to specify a iSCSI request timeout to detect 2529stalled requests and force a reestablishment of the session. The timeout 2530is specified in seconds. The default is 0 which means no timeout. Libiscsi 25311.15.0 or greater is required for this feature. 2532 2533Example (without authentication): 2534@example 2535qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \ 2536 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \ 2537 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 2538@end example 2539 2540Example (CHAP username/password via URL): 2541@example 2542qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1 2543@end example 2544 2545Example (CHAP username/password via environment variables): 2546@example 2547LIBISCSI_CHAP_USERNAME="user" \ 2548LIBISCSI_CHAP_PASSWORD="password" \ 2549qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 2550@end example 2551 2552iSCSI support is an optional feature of QEMU and only available when 2553compiled and linked against libiscsi. 2554ETEXI 2555DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi, 2556 "-iscsi [user=user][,password=password]\n" 2557 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n" 2558 " [,initiator-name=initiator-iqn][,id=target-iqn]\n" 2559 " [,timeout=timeout]\n" 2560 " iSCSI session parameters\n", QEMU_ARCH_ALL) 2561STEXI 2562 2563iSCSI parameters such as username and password can also be specified via 2564a configuration file. See qemu-doc for more information and examples. 2565 2566@item NBD 2567QEMU supports NBD (Network Block Devices) both using TCP protocol as well 2568as Unix Domain Sockets. 2569 2570Syntax for specifying a NBD device using TCP 2571``nbd:<server-ip>:<port>[:exportname=<export>]'' 2572 2573Syntax for specifying a NBD device using Unix Domain Sockets 2574``nbd:unix:<domain-socket>[:exportname=<export>]'' 2575 2576 2577Example for TCP 2578@example 2579qemu-system-i386 --drive file=nbd:192.0.2.1:30000 2580@end example 2581 2582Example for Unix Domain Sockets 2583@example 2584qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket 2585@end example 2586 2587@item SSH 2588QEMU supports SSH (Secure Shell) access to remote disks. 2589 2590Examples: 2591@example 2592qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img 2593qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img 2594@end example 2595 2596Currently authentication must be done using ssh-agent. Other 2597authentication methods may be supported in future. 2598 2599@item Sheepdog 2600Sheepdog is a distributed storage system for QEMU. 2601QEMU supports using either local sheepdog devices or remote networked 2602devices. 2603 2604Syntax for specifying a sheepdog device 2605@example 2606sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag] 2607@end example 2608 2609Example 2610@example 2611qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine 2612@end example 2613 2614See also @url{https://sheepdog.github.io/sheepdog/}. 2615 2616@item GlusterFS 2617GlusterFS is a user space distributed file system. 2618QEMU supports the use of GlusterFS volumes for hosting VM disk images using 2619TCP, Unix Domain Sockets and RDMA transport protocols. 2620 2621Syntax for specifying a VM disk image on GlusterFS volume is 2622@example 2623 2624URI: 2625gluster[+type]://[host[:port]]/volume/path[?socket=...][,debug=N][,logfile=...] 2626 2627JSON: 2628'json:@{"driver":"qcow2","file":@{"driver":"gluster","volume":"testvol","path":"a.img","debug":N,"logfile":"...", 2629@ "server":[@{"type":"tcp","host":"...","port":"..."@}, 2630@ @{"type":"unix","socket":"..."@}]@}@}' 2631@end example 2632 2633 2634Example 2635@example 2636URI: 2637qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img, 2638@ file.debug=9,file.logfile=/var/log/qemu-gluster.log 2639 2640JSON: 2641qemu-system-x86_64 'json:@{"driver":"qcow2", 2642@ "file":@{"driver":"gluster", 2643@ "volume":"testvol","path":"a.img", 2644@ "debug":9,"logfile":"/var/log/qemu-gluster.log", 2645@ "server":[@{"type":"tcp","host":"1.2.3.4","port":24007@}, 2646@ @{"type":"unix","socket":"/var/run/glusterd.socket"@}]@}@}' 2647qemu-system-x86_64 -drive driver=qcow2,file.driver=gluster,file.volume=testvol,file.path=/path/a.img, 2648@ file.debug=9,file.logfile=/var/log/qemu-gluster.log, 2649@ file.server.0.type=tcp,file.server.0.host=1.2.3.4,file.server.0.port=24007, 2650@ file.server.1.type=unix,file.server.1.socket=/var/run/glusterd.socket 2651@end example 2652 2653See also @url{http://www.gluster.org}. 2654 2655@item HTTP/HTTPS/FTP/FTPS 2656QEMU supports read-only access to files accessed over http(s) and ftp(s). 2657 2658Syntax using a single filename: 2659@example 2660<protocol>://[<username>[:<password>]@@]<host>/<path> 2661@end example 2662 2663where: 2664@table @option 2665@item protocol 2666'http', 'https', 'ftp', or 'ftps'. 2667 2668@item username 2669Optional username for authentication to the remote server. 2670 2671@item password 2672Optional password for authentication to the remote server. 2673 2674@item host 2675Address of the remote server. 2676 2677@item path 2678Path on the remote server, including any query string. 2679@end table 2680 2681The following options are also supported: 2682@table @option 2683@item url 2684The full URL when passing options to the driver explicitly. 2685 2686@item readahead 2687The amount of data to read ahead with each range request to the remote server. 2688This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it 2689does not have a suffix, it will be assumed to be in bytes. The value must be a 2690multiple of 512 bytes. It defaults to 256k. 2691 2692@item sslverify 2693Whether to verify the remote server's certificate when connecting over SSL. It 2694can have the value 'on' or 'off'. It defaults to 'on'. 2695 2696@item cookie 2697Send this cookie (it can also be a list of cookies separated by ';') with 2698each outgoing request. Only supported when using protocols such as HTTP 2699which support cookies, otherwise ignored. 2700 2701@item timeout 2702Set the timeout in seconds of the CURL connection. This timeout is the time 2703that CURL waits for a response from the remote server to get the size of the 2704image to be downloaded. If not set, the default timeout of 5 seconds is used. 2705@end table 2706 2707Note that when passing options to qemu explicitly, @option{driver} is the value 2708of <protocol>. 2709 2710Example: boot from a remote Fedora 20 live ISO image 2711@example 2712qemu-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 2713 2714qemu-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 2715@end example 2716 2717Example: boot from a remote Fedora 20 cloud image using a local overlay for 2718writes, copy-on-read, and a readahead of 64k 2719@example 2720qemu-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 2721 2722qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on 2723@end example 2724 2725Example: boot from an image stored on a VMware vSphere server with a self-signed 2726certificate using a local overlay for writes, a readahead of 64k and a timeout 2727of 10 seconds. 2728@example 2729qemu-img create -f qcow2 -o backing_file='json:@{"file.driver":"https",, "file.url":"https://user:password@@vsphere.example.com/folder/test/test-flat.vmdk?dcPath=Datacenter&dsName=datastore1",, "file.sslverify":"off",, "file.readahead":"64k",, "file.timeout":10@}' /tmp/test.qcow2 2730 2731qemu-system-x86_64 -drive file=/tmp/test.qcow2 2732@end example 2733ETEXI 2734 2735STEXI 2736@end table 2737ETEXI 2738 2739DEFHEADING(Bluetooth(R) options) 2740STEXI 2741@table @option 2742ETEXI 2743 2744DEF("bt", HAS_ARG, QEMU_OPTION_bt, \ 2745 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \ 2746 "-bt hci,host[:id]\n" \ 2747 " use host's HCI with the given name\n" \ 2748 "-bt hci[,vlan=n]\n" \ 2749 " emulate a standard HCI in virtual scatternet 'n'\n" \ 2750 "-bt vhci[,vlan=n]\n" \ 2751 " add host computer to virtual scatternet 'n' using VHCI\n" \ 2752 "-bt device:dev[,vlan=n]\n" \ 2753 " emulate a bluetooth device 'dev' in scatternet 'n'\n", 2754 QEMU_ARCH_ALL) 2755STEXI 2756@item -bt hci[...] 2757@findex -bt 2758Defines the function of the corresponding Bluetooth HCI. -bt options 2759are matched with the HCIs present in the chosen machine type. For 2760example when emulating a machine with only one HCI built into it, only 2761the first @code{-bt hci[...]} option is valid and defines the HCI's 2762logic. The Transport Layer is decided by the machine type. Currently 2763the machines @code{n800} and @code{n810} have one HCI and all other 2764machines have none. 2765 2766@anchor{bt-hcis} 2767The following three types are recognized: 2768 2769@table @option 2770@item -bt hci,null 2771(default) The corresponding Bluetooth HCI assumes no internal logic 2772and will not respond to any HCI commands or emit events. 2773 2774@item -bt hci,host[:@var{id}] 2775(@code{bluez} only) The corresponding HCI passes commands / events 2776to / from the physical HCI identified by the name @var{id} (default: 2777@code{hci0}) on the computer running QEMU. Only available on @code{bluez} 2778capable systems like Linux. 2779 2780@item -bt hci[,vlan=@var{n}] 2781Add a virtual, standard HCI that will participate in the Bluetooth 2782scatternet @var{n} (default @code{0}). Similarly to @option{-net} 2783VLANs, devices inside a bluetooth network @var{n} can only communicate 2784with other devices in the same network (scatternet). 2785@end table 2786 2787@item -bt vhci[,vlan=@var{n}] 2788(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached 2789to the host bluetooth stack instead of to the emulated target. This 2790allows the host and target machines to participate in a common scatternet 2791and communicate. Requires the Linux @code{vhci} driver installed. Can 2792be used as following: 2793 2794@example 2795qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5 2796@end example 2797 2798@item -bt device:@var{dev}[,vlan=@var{n}] 2799Emulate a bluetooth device @var{dev} and place it in network @var{n} 2800(default @code{0}). QEMU can only emulate one type of bluetooth devices 2801currently: 2802 2803@table @option 2804@item keyboard 2805Virtual wireless keyboard implementing the HIDP bluetooth profile. 2806@end table 2807ETEXI 2808 2809STEXI 2810@end table 2811ETEXI 2812DEFHEADING() 2813 2814#ifdef CONFIG_TPM 2815DEFHEADING(TPM device options) 2816 2817DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \ 2818 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n" 2819 " use path to provide path to a character device; default is /dev/tpm0\n" 2820 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n" 2821 " not provided it will be searched for in /sys/class/misc/tpm?/device\n", 2822 QEMU_ARCH_ALL) 2823STEXI 2824 2825The general form of a TPM device option is: 2826@table @option 2827 2828@item -tpmdev @var{backend} ,id=@var{id} [,@var{options}] 2829@findex -tpmdev 2830Backend type must be: 2831@option{passthrough}. 2832 2833The specific backend type will determine the applicable options. 2834The @code{-tpmdev} option creates the TPM backend and requires a 2835@code{-device} option that specifies the TPM frontend interface model. 2836 2837Options to each backend are described below. 2838 2839Use 'help' to print all available TPM backend types. 2840@example 2841qemu -tpmdev help 2842@end example 2843 2844@item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path} 2845 2846(Linux-host only) Enable access to the host's TPM using the passthrough 2847driver. 2848 2849@option{path} specifies the path to the host's TPM device, i.e., on 2850a Linux host this would be @code{/dev/tpm0}. 2851@option{path} is optional and by default @code{/dev/tpm0} is used. 2852 2853@option{cancel-path} specifies the path to the host TPM device's sysfs 2854entry allowing for cancellation of an ongoing TPM command. 2855@option{cancel-path} is optional and by default QEMU will search for the 2856sysfs entry to use. 2857 2858Some notes about using the host's TPM with the passthrough driver: 2859 2860The TPM device accessed by the passthrough driver must not be 2861used by any other application on the host. 2862 2863Since the host's firmware (BIOS/UEFI) has already initialized the TPM, 2864the VM's firmware (BIOS/UEFI) will not be able to initialize the 2865TPM again and may therefore not show a TPM-specific menu that would 2866otherwise allow the user to configure the TPM, e.g., allow the user to 2867enable/disable or activate/deactivate the TPM. 2868Further, if TPM ownership is released from within a VM then the host's TPM 2869will get disabled and deactivated. To enable and activate the 2870TPM again afterwards, the host has to be rebooted and the user is 2871required to enter the firmware's menu to enable and activate the TPM. 2872If the TPM is left disabled and/or deactivated most TPM commands will fail. 2873 2874To create a passthrough TPM use the following two options: 2875@example 2876-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0 2877@end example 2878Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by 2879@code{tpmdev=tpm0} in the device option. 2880 2881@end table 2882 2883ETEXI 2884 2885DEFHEADING() 2886 2887#endif 2888 2889DEFHEADING(Linux/Multiboot boot specific) 2890STEXI 2891 2892When using these options, you can use a given Linux or Multiboot 2893kernel without installing it in the disk image. It can be useful 2894for easier testing of various kernels. 2895 2896@table @option 2897ETEXI 2898 2899DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \ 2900 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL) 2901STEXI 2902@item -kernel @var{bzImage} 2903@findex -kernel 2904Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel 2905or in multiboot format. 2906ETEXI 2907 2908DEF("append", HAS_ARG, QEMU_OPTION_append, \ 2909 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL) 2910STEXI 2911@item -append @var{cmdline} 2912@findex -append 2913Use @var{cmdline} as kernel command line 2914ETEXI 2915 2916DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \ 2917 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL) 2918STEXI 2919@item -initrd @var{file} 2920@findex -initrd 2921Use @var{file} as initial ram disk. 2922 2923@item -initrd "@var{file1} arg=foo,@var{file2}" 2924 2925This syntax is only available with multiboot. 2926 2927Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the 2928first module. 2929ETEXI 2930 2931DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \ 2932 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL) 2933STEXI 2934@item -dtb @var{file} 2935@findex -dtb 2936Use @var{file} as a device tree binary (dtb) image and pass it to the kernel 2937on boot. 2938ETEXI 2939 2940STEXI 2941@end table 2942ETEXI 2943DEFHEADING() 2944 2945DEFHEADING(Debug/Expert options) 2946STEXI 2947@table @option 2948ETEXI 2949 2950DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg, 2951 "-fw_cfg [name=]<name>,file=<file>\n" 2952 " add named fw_cfg entry with contents from file\n" 2953 "-fw_cfg [name=]<name>,string=<str>\n" 2954 " add named fw_cfg entry with contents from string\n", 2955 QEMU_ARCH_ALL) 2956STEXI 2957 2958@item -fw_cfg [name=]@var{name},file=@var{file} 2959@findex -fw_cfg 2960Add named fw_cfg entry with contents from file @var{file}. 2961 2962@item -fw_cfg [name=]@var{name},string=@var{str} 2963Add named fw_cfg entry with contents from string @var{str}. 2964 2965The terminating NUL character of the contents of @var{str} will not be 2966included as part of the fw_cfg item data. To insert contents with 2967embedded NUL characters, you have to use the @var{file} parameter. 2968 2969The fw_cfg entries are passed by QEMU through to the guest. 2970 2971Example: 2972@example 2973 -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin 2974@end example 2975creates an fw_cfg entry named opt/com.mycompany/blob with contents 2976from ./my_blob.bin. 2977 2978ETEXI 2979 2980DEF("serial", HAS_ARG, QEMU_OPTION_serial, \ 2981 "-serial dev redirect the serial port to char device 'dev'\n", 2982 QEMU_ARCH_ALL) 2983STEXI 2984@item -serial @var{dev} 2985@findex -serial 2986Redirect the virtual serial port to host character device 2987@var{dev}. The default device is @code{vc} in graphical mode and 2988@code{stdio} in non graphical mode. 2989 2990This option can be used several times to simulate up to 4 serial 2991ports. 2992 2993Use @code{-serial none} to disable all serial ports. 2994 2995Available character devices are: 2996@table @option 2997@item vc[:@var{W}x@var{H}] 2998Virtual console. Optionally, a width and height can be given in pixel with 2999@example 3000vc:800x600 3001@end example 3002It is also possible to specify width or height in characters: 3003@example 3004vc:80Cx24C 3005@end example 3006@item pty 3007[Linux only] Pseudo TTY (a new PTY is automatically allocated) 3008@item none 3009No device is allocated. 3010@item null 3011void device 3012@item chardev:@var{id} 3013Use a named character device defined with the @code{-chardev} option. 3014@item /dev/XXX 3015[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port 3016parameters are set according to the emulated ones. 3017@item /dev/parport@var{N} 3018[Linux only, parallel port only] Use host parallel port 3019@var{N}. Currently SPP and EPP parallel port features can be used. 3020@item file:@var{filename} 3021Write output to @var{filename}. No character can be read. 3022@item stdio 3023[Unix only] standard input/output 3024@item pipe:@var{filename} 3025name pipe @var{filename} 3026@item COM@var{n} 3027[Windows only] Use host serial port @var{n} 3028@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}] 3029This implements UDP Net Console. 3030When @var{remote_host} or @var{src_ip} are not specified 3031they default to @code{0.0.0.0}. 3032When not using a specified @var{src_port} a random port is automatically chosen. 3033 3034If you just want a simple readonly console you can use @code{netcat} or 3035@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as: 3036@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it 3037will appear in the netconsole session. 3038 3039If you plan to send characters back via netconsole or you want to stop 3040and start QEMU a lot of times, you should have QEMU use the same 3041source port each time by using something like @code{-serial 3042udp::4555@@:4556} to QEMU. Another approach is to use a patched 3043version of netcat which can listen to a TCP port and send and receive 3044characters via udp. If you have a patched version of netcat which 3045activates telnet remote echo and single char transfer, then you can 3046use the following options to set up a netcat redirector to allow 3047telnet on port 5555 to access the QEMU port. 3048@table @code 3049@item QEMU Options: 3050-serial udp::4555@@:4556 3051@item netcat options: 3052-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T 3053@item telnet options: 3054localhost 5555 3055@end table 3056 3057@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}] 3058The TCP Net Console has two modes of operation. It can send the serial 3059I/O to a location or wait for a connection from a location. By default 3060the TCP Net Console is sent to @var{host} at the @var{port}. If you use 3061the @var{server} option QEMU will wait for a client socket application 3062to connect to the port before continuing, unless the @code{nowait} 3063option was specified. The @code{nodelay} option disables the Nagle buffering 3064algorithm. The @code{reconnect} option only applies if @var{noserver} is 3065set, if the connection goes down it will attempt to reconnect at the 3066given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only 3067one TCP connection at a time is accepted. You can use @code{telnet} to 3068connect to the corresponding character device. 3069@table @code 3070@item Example to send tcp console to 192.168.0.2 port 4444 3071-serial tcp:192.168.0.2:4444 3072@item Example to listen and wait on port 4444 for connection 3073-serial tcp::4444,server 3074@item Example to not wait and listen on ip 192.168.0.100 port 4444 3075-serial tcp:192.168.0.100:4444,server,nowait 3076@end table 3077 3078@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay] 3079The telnet protocol is used instead of raw tcp sockets. The options 3080work the same as if you had specified @code{-serial tcp}. The 3081difference is that the port acts like a telnet server or client using 3082telnet option negotiation. This will also allow you to send the 3083MAGIC_SYSRQ sequence if you use a telnet that supports sending the break 3084sequence. Typically in unix telnet you do it with Control-] and then 3085type "send break" followed by pressing the enter key. 3086 3087@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}] 3088A unix domain socket is used instead of a tcp socket. The option works the 3089same as if you had specified @code{-serial tcp} except the unix domain socket 3090@var{path} is used for connections. 3091 3092@item mon:@var{dev_string} 3093This is a special option to allow the monitor to be multiplexed onto 3094another serial port. The monitor is accessed with key sequence of 3095@key{Control-a} and then pressing @key{c}. 3096@var{dev_string} should be any one of the serial devices specified 3097above. An example to multiplex the monitor onto a telnet server 3098listening on port 4444 would be: 3099@table @code 3100@item -serial mon:telnet::4444,server,nowait 3101@end table 3102When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate 3103QEMU any more but will be passed to the guest instead. 3104 3105@item braille 3106Braille device. This will use BrlAPI to display the braille output on a real 3107or fake device. 3108 3109@item msmouse 3110Three button serial mouse. Configure the guest to use Microsoft protocol. 3111@end table 3112ETEXI 3113 3114DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \ 3115 "-parallel dev redirect the parallel port to char device 'dev'\n", 3116 QEMU_ARCH_ALL) 3117STEXI 3118@item -parallel @var{dev} 3119@findex -parallel 3120Redirect the virtual parallel port to host device @var{dev} (same 3121devices as the serial port). On Linux hosts, @file{/dev/parportN} can 3122be used to use hardware devices connected on the corresponding host 3123parallel port. 3124 3125This option can be used several times to simulate up to 3 parallel 3126ports. 3127 3128Use @code{-parallel none} to disable all parallel ports. 3129ETEXI 3130 3131DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \ 3132 "-monitor dev redirect the monitor to char device 'dev'\n", 3133 QEMU_ARCH_ALL) 3134STEXI 3135@item -monitor @var{dev} 3136@findex -monitor 3137Redirect the monitor to host device @var{dev} (same devices as the 3138serial port). 3139The default device is @code{vc} in graphical mode and @code{stdio} in 3140non graphical mode. 3141Use @code{-monitor none} to disable the default monitor. 3142ETEXI 3143DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \ 3144 "-qmp dev like -monitor but opens in 'control' mode\n", 3145 QEMU_ARCH_ALL) 3146STEXI 3147@item -qmp @var{dev} 3148@findex -qmp 3149Like -monitor but opens in 'control' mode. 3150ETEXI 3151DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \ 3152 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n", 3153 QEMU_ARCH_ALL) 3154STEXI 3155@item -qmp-pretty @var{dev} 3156@findex -qmp-pretty 3157Like -qmp but uses pretty JSON formatting. 3158ETEXI 3159 3160DEF("mon", HAS_ARG, QEMU_OPTION_mon, \ 3161 "-mon [chardev=]name[,mode=readline|control]\n", QEMU_ARCH_ALL) 3162STEXI 3163@item -mon [chardev=]name[,mode=readline|control] 3164@findex -mon 3165Setup monitor on chardev @var{name}. 3166ETEXI 3167 3168DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ 3169 "-debugcon dev redirect the debug console to char device 'dev'\n", 3170 QEMU_ARCH_ALL) 3171STEXI 3172@item -debugcon @var{dev} 3173@findex -debugcon 3174Redirect the debug console to host device @var{dev} (same devices as the 3175serial port). The debug console is an I/O port which is typically port 31760xe9; writing to that I/O port sends output to this device. 3177The default device is @code{vc} in graphical mode and @code{stdio} in 3178non graphical mode. 3179ETEXI 3180 3181DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ 3182 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL) 3183STEXI 3184@item -pidfile @var{file} 3185@findex -pidfile 3186Store the QEMU process PID in @var{file}. It is useful if you launch QEMU 3187from a script. 3188ETEXI 3189 3190DEF("singlestep", 0, QEMU_OPTION_singlestep, \ 3191 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) 3192STEXI 3193@item -singlestep 3194@findex -singlestep 3195Run the emulation in single step mode. 3196ETEXI 3197 3198DEF("S", 0, QEMU_OPTION_S, \ 3199 "-S freeze CPU at startup (use 'c' to start execution)\n", 3200 QEMU_ARCH_ALL) 3201STEXI 3202@item -S 3203@findex -S 3204Do not start CPU at startup (you must type 'c' in the monitor). 3205ETEXI 3206 3207DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, 3208 "-realtime [mlock=on|off]\n" 3209 " run qemu with realtime features\n" 3210 " mlock=on|off controls mlock support (default: on)\n", 3211 QEMU_ARCH_ALL) 3212STEXI 3213@item -realtime mlock=on|off 3214@findex -realtime 3215Run qemu with realtime features. 3216mlocking qemu and guest memory can be enabled via @option{mlock=on} 3217(enabled by default). 3218ETEXI 3219 3220DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ 3221 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) 3222STEXI 3223@item -gdb @var{dev} 3224@findex -gdb 3225Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical 3226connections will likely be TCP-based, but also UDP, pseudo TTY, or even 3227stdio are reasonable use case. The latter is allowing to start QEMU from 3228within gdb and establish the connection via a pipe: 3229@example 3230(gdb) target remote | exec qemu-system-i386 -gdb stdio ... 3231@end example 3232ETEXI 3233 3234DEF("s", 0, QEMU_OPTION_s, \ 3235 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n", 3236 QEMU_ARCH_ALL) 3237STEXI 3238@item -s 3239@findex -s 3240Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234 3241(@pxref{gdb_usage}). 3242ETEXI 3243 3244DEF("d", HAS_ARG, QEMU_OPTION_d, \ 3245 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n", 3246 QEMU_ARCH_ALL) 3247STEXI 3248@item -d @var{item1}[,...] 3249@findex -d 3250Enable logging of specified items. Use '-d help' for a list of log items. 3251ETEXI 3252 3253DEF("D", HAS_ARG, QEMU_OPTION_D, \ 3254 "-D logfile output log to logfile (default stderr)\n", 3255 QEMU_ARCH_ALL) 3256STEXI 3257@item -D @var{logfile} 3258@findex -D 3259Output log in @var{logfile} instead of to stderr 3260ETEXI 3261 3262DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \ 3263 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n", 3264 QEMU_ARCH_ALL) 3265STEXI 3266@item -dfilter @var{range1}[,...] 3267@findex -dfilter 3268Filter debug output to that relevant to a range of target addresses. The filter 3269spec can be either @var{start}+@var{size}, @var{start}-@var{size} or 3270@var{start}..@var{end} where @var{start} @var{end} and @var{size} are the 3271addresses and sizes required. For example: 3272@example 3273 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000 3274@end example 3275Will dump output for any code in the 0x1000 sized block starting at 0x8000 and 3276the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized 3277block starting at 0xffffffc00005f000. 3278ETEXI 3279 3280DEF("L", HAS_ARG, QEMU_OPTION_L, \ 3281 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", 3282 QEMU_ARCH_ALL) 3283STEXI 3284@item -L @var{path} 3285@findex -L 3286Set the directory for the BIOS, VGA BIOS and keymaps. 3287 3288To list all the data directories, use @code{-L help}. 3289ETEXI 3290 3291DEF("bios", HAS_ARG, QEMU_OPTION_bios, \ 3292 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL) 3293STEXI 3294@item -bios @var{file} 3295@findex -bios 3296Set the filename for the BIOS. 3297ETEXI 3298 3299DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \ 3300 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL) 3301STEXI 3302@item -enable-kvm 3303@findex -enable-kvm 3304Enable KVM full virtualization support. This option is only available 3305if KVM support is enabled when compiling. 3306ETEXI 3307 3308DEF("enable-hax", 0, QEMU_OPTION_enable_hax, \ 3309 "-enable-hax enable HAX virtualization support\n", QEMU_ARCH_I386) 3310STEXI 3311@item -enable-hax 3312@findex -enable-hax 3313Enable HAX (Hardware-based Acceleration eXecution) support. This option 3314is only available if HAX support is enabled when compiling. HAX is only 3315applicable to MAC and Windows platform, and thus does not conflict with 3316KVM. 3317ETEXI 3318 3319DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, 3320 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) 3321DEF("xen-create", 0, QEMU_OPTION_xen_create, 3322 "-xen-create create domain using xen hypercalls, bypassing xend\n" 3323 " warning: should not be used when xend is in use\n", 3324 QEMU_ARCH_ALL) 3325DEF("xen-attach", 0, QEMU_OPTION_xen_attach, 3326 "-xen-attach attach to existing xen domain\n" 3327 " xend will use this when starting QEMU\n", 3328 QEMU_ARCH_ALL) 3329STEXI 3330@item -xen-domid @var{id} 3331@findex -xen-domid 3332Specify xen guest domain @var{id} (XEN only). 3333@item -xen-create 3334@findex -xen-create 3335Create domain using xen hypercalls, bypassing xend. 3336Warning: should not be used when xend is in use (XEN only). 3337@item -xen-attach 3338@findex -xen-attach 3339Attach to existing xen domain. 3340xend will use this when starting QEMU (XEN only). 3341ETEXI 3342 3343DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \ 3344 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL) 3345STEXI 3346@item -no-reboot 3347@findex -no-reboot 3348Exit instead of rebooting. 3349ETEXI 3350 3351DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \ 3352 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL) 3353STEXI 3354@item -no-shutdown 3355@findex -no-shutdown 3356Don't exit QEMU on guest shutdown, but instead only stop the emulation. 3357This allows for instance switching to monitor to commit changes to the 3358disk image. 3359ETEXI 3360 3361DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ 3362 "-loadvm [tag|id]\n" \ 3363 " start right away with a saved state (loadvm in monitor)\n", 3364 QEMU_ARCH_ALL) 3365STEXI 3366@item -loadvm @var{file} 3367@findex -loadvm 3368Start right away with a saved state (@code{loadvm} in monitor) 3369ETEXI 3370 3371#ifndef _WIN32 3372DEF("daemonize", 0, QEMU_OPTION_daemonize, \ 3373 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) 3374#endif 3375STEXI 3376@item -daemonize 3377@findex -daemonize 3378Daemonize the QEMU process after initialization. QEMU will not detach from 3379standard IO until it is ready to receive connections on any of its devices. 3380This option is a useful way for external programs to launch QEMU without having 3381to cope with initialization race conditions. 3382ETEXI 3383 3384DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \ 3385 "-option-rom rom load a file, rom, into the option ROM space\n", 3386 QEMU_ARCH_ALL) 3387STEXI 3388@item -option-rom @var{file} 3389@findex -option-rom 3390Load the contents of @var{file} as an option ROM. 3391This option is useful to load things like EtherBoot. 3392ETEXI 3393 3394HXCOMM Silently ignored for compatibility 3395DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL) 3396 3397HXCOMM Options deprecated by -rtc 3398DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL) 3399DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL) 3400 3401DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \ 3402 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \ 3403 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n", 3404 QEMU_ARCH_ALL) 3405 3406STEXI 3407 3408@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew] 3409@findex -rtc 3410Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current 3411UTC or local time, respectively. @code{localtime} is required for correct date in 3412MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the 3413format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC. 3414 3415By default the RTC is driven by the host system time. This allows using of the 3416RTC as accurate reference clock inside the guest, specifically if the host 3417time is smoothly following an accurate external reference clock, e.g. via NTP. 3418If you want to isolate the guest time from the host, you can set @option{clock} 3419to @code{rt} instead. To even prevent it from progressing during suspension, 3420you can set it to @code{vm}. 3421 3422Enable @option{driftfix} (i386 targets only) if you experience time drift problems, 3423specifically with Windows' ACPI HAL. This option will try to figure out how 3424many timer interrupts were not processed by the Windows guest and will 3425re-inject them. 3426ETEXI 3427 3428DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ 3429 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \ 3430 " enable virtual instruction counter with 2^N clock ticks per\n" \ 3431 " instruction, enable aligning the host and virtual clocks\n" \ 3432 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL) 3433STEXI 3434@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}] 3435@findex -icount 3436Enable virtual instruction counter. The virtual cpu will execute one 3437instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified 3438then the virtual cpu speed will be automatically adjusted to keep virtual 3439time within a few seconds of real time. 3440 3441When the virtual cpu is sleeping, the virtual time will advance at default 3442speed unless @option{sleep=on|off} is specified. 3443With @option{sleep=on|off}, the virtual time will jump to the next timer deadline 3444instantly whenever the virtual cpu goes to sleep mode and will not advance 3445if no timer is enabled. This behavior give deterministic execution times from 3446the guest point of view. 3447 3448Note that while this option can give deterministic behavior, it does not 3449provide cycle accurate emulation. Modern CPUs contain superscalar out of 3450order cores with complex cache hierarchies. The number of instructions 3451executed often has little or no correlation with actual performance. 3452 3453@option{align=on} will activate the delay algorithm which will try 3454to synchronise the host clock and the virtual clock. The goal is to 3455have a guest running at the real frequency imposed by the shift option. 3456Whenever the guest clock is behind the host clock and if 3457@option{align=on} is specified then we print a message to the user 3458to inform about the delay. 3459Currently this option does not work when @option{shift} is @code{auto}. 3460Note: The sync algorithm will work for those shift values for which 3461the guest clock runs ahead of the host clock. Typically this happens 3462when the shift value is high (how high depends on the host machine). 3463 3464When @option{rr} option is specified deterministic record/replay is enabled. 3465Replay log is written into @var{filename} file in record mode and 3466read from this file in replay mode. 3467 3468Option rrsnapshot is used to create new vm snapshot named @var{snapshot} 3469at the start of execution recording. In replay mode this option is used 3470to load the initial VM state. 3471ETEXI 3472 3473DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ 3474 "-watchdog model\n" \ 3475 " enable virtual hardware watchdog [default=none]\n", 3476 QEMU_ARCH_ALL) 3477STEXI 3478@item -watchdog @var{model} 3479@findex -watchdog 3480Create a virtual hardware watchdog device. Once enabled (by a guest 3481action), the watchdog must be periodically polled by an agent inside 3482the guest or else the guest will be restarted. Choose a model for 3483which your guest has drivers. 3484 3485The @var{model} is the model of hardware watchdog to emulate. Use 3486@code{-watchdog help} to list available hardware models. Only one 3487watchdog can be enabled for a guest. 3488 3489The following models may be available: 3490@table @option 3491@item ib700 3492iBASE 700 is a very simple ISA watchdog with a single timer. 3493@item i6300esb 3494Intel 6300ESB I/O controller hub is a much more featureful PCI-based 3495dual-timer watchdog. 3496@item diag288 3497A virtual watchdog for s390x backed by the diagnose 288 hypercall 3498(currently KVM only). 3499@end table 3500ETEXI 3501 3502DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \ 3503 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \ 3504 " action when watchdog fires [default=reset]\n", 3505 QEMU_ARCH_ALL) 3506STEXI 3507@item -watchdog-action @var{action} 3508@findex -watchdog-action 3509 3510The @var{action} controls what QEMU will do when the watchdog timer 3511expires. 3512The default is 3513@code{reset} (forcefully reset the guest). 3514Other possible actions are: 3515@code{shutdown} (attempt to gracefully shutdown the guest), 3516@code{poweroff} (forcefully poweroff the guest), 3517@code{pause} (pause the guest), 3518@code{debug} (print a debug message and continue), or 3519@code{none} (do nothing). 3520 3521Note that the @code{shutdown} action requires that the guest responds 3522to ACPI signals, which it may not be able to do in the sort of 3523situations where the watchdog would have expired, and thus 3524@code{-watchdog-action shutdown} is not recommended for production use. 3525 3526Examples: 3527 3528@table @code 3529@item -watchdog i6300esb -watchdog-action pause 3530@itemx -watchdog ib700 3531@end table 3532ETEXI 3533 3534DEF("echr", HAS_ARG, QEMU_OPTION_echr, \ 3535 "-echr chr set terminal escape character instead of ctrl-a\n", 3536 QEMU_ARCH_ALL) 3537STEXI 3538 3539@item -echr @var{numeric_ascii_value} 3540@findex -echr 3541Change the escape character used for switching to the monitor when using 3542monitor and serial sharing. The default is @code{0x01} when using the 3543@code{-nographic} option. @code{0x01} is equal to pressing 3544@code{Control-a}. You can select a different character from the ascii 3545control keys where 1 through 26 map to Control-a through Control-z. For 3546instance you could use the either of the following to change the escape 3547character to Control-t. 3548@table @code 3549@item -echr 0x14 3550@itemx -echr 20 3551@end table 3552ETEXI 3553 3554DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \ 3555 "-virtioconsole c\n" \ 3556 " set virtio console\n", QEMU_ARCH_ALL) 3557STEXI 3558@item -virtioconsole @var{c} 3559@findex -virtioconsole 3560Set virtio console. 3561 3562This option is maintained for backward compatibility. 3563 3564Please use @code{-device virtconsole} for the new way of invocation. 3565ETEXI 3566 3567DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \ 3568 "-show-cursor show cursor\n", QEMU_ARCH_ALL) 3569STEXI 3570@item -show-cursor 3571@findex -show-cursor 3572Show cursor. 3573ETEXI 3574 3575DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \ 3576 "-tb-size n set TB size\n", QEMU_ARCH_ALL) 3577STEXI 3578@item -tb-size @var{n} 3579@findex -tb-size 3580Set TB size. 3581ETEXI 3582 3583DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \ 3584 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \ 3585 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \ 3586 "-incoming unix:socketpath\n" \ 3587 " prepare for incoming migration, listen on\n" \ 3588 " specified protocol and socket address\n" \ 3589 "-incoming fd:fd\n" \ 3590 "-incoming exec:cmdline\n" \ 3591 " accept incoming migration on given file descriptor\n" \ 3592 " or from given external command\n" \ 3593 "-incoming defer\n" \ 3594 " wait for the URI to be specified via migrate_incoming\n", 3595 QEMU_ARCH_ALL) 3596STEXI 3597@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6] 3598@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6] 3599@findex -incoming 3600Prepare for incoming migration, listen on a given tcp port. 3601 3602@item -incoming unix:@var{socketpath} 3603Prepare for incoming migration, listen on a given unix socket. 3604 3605@item -incoming fd:@var{fd} 3606Accept incoming migration from a given filedescriptor. 3607 3608@item -incoming exec:@var{cmdline} 3609Accept incoming migration as an output from specified external command. 3610 3611@item -incoming defer 3612Wait for the URI to be specified via migrate_incoming. The monitor can 3613be used to change settings (such as migration parameters) prior to issuing 3614the migrate_incoming to allow the migration to begin. 3615ETEXI 3616 3617DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \ 3618 "-only-migratable allow only migratable devices\n", QEMU_ARCH_ALL) 3619STEXI 3620@item -only-migratable 3621@findex -only-migratable 3622Only allow migratable devices. Devices will not be allowed to enter an 3623unmigratable state. 3624ETEXI 3625 3626DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \ 3627 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL) 3628STEXI 3629@item -nodefaults 3630@findex -nodefaults 3631Don't create default devices. Normally, QEMU sets the default devices like serial 3632port, parallel port, virtual console, monitor device, VGA adapter, floppy and 3633CD-ROM drive and others. The @code{-nodefaults} option will disable all those 3634default devices. 3635ETEXI 3636 3637#ifndef _WIN32 3638DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \ 3639 "-chroot dir chroot to dir just before starting the VM\n", 3640 QEMU_ARCH_ALL) 3641#endif 3642STEXI 3643@item -chroot @var{dir} 3644@findex -chroot 3645Immediately before starting guest execution, chroot to the specified 3646directory. Especially useful in combination with -runas. 3647ETEXI 3648 3649#ifndef _WIN32 3650DEF("runas", HAS_ARG, QEMU_OPTION_runas, \ 3651 "-runas user change to user id user just before starting the VM\n", 3652 QEMU_ARCH_ALL) 3653#endif 3654STEXI 3655@item -runas @var{user} 3656@findex -runas 3657Immediately before starting guest execution, drop root privileges, switching 3658to the specified user. 3659ETEXI 3660 3661DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env, 3662 "-prom-env variable=value\n" 3663 " set OpenBIOS nvram variables\n", 3664 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 3665STEXI 3666@item -prom-env @var{variable}=@var{value} 3667@findex -prom-env 3668Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only). 3669ETEXI 3670DEF("semihosting", 0, QEMU_OPTION_semihosting, 3671 "-semihosting semihosting mode\n", 3672 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3673 QEMU_ARCH_MIPS) 3674STEXI 3675@item -semihosting 3676@findex -semihosting 3677Enable semihosting mode (ARM, M68K, Xtensa, MIPS only). 3678ETEXI 3679DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config, 3680 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \ 3681 " semihosting configuration\n", 3682QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3683QEMU_ARCH_MIPS) 3684STEXI 3685@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]] 3686@findex -semihosting-config 3687Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only). 3688@table @option 3689@item target=@code{native|gdb|auto} 3690Defines where the semihosting calls will be addressed, to QEMU (@code{native}) 3691or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb} 3692during debug sessions and @code{native} otherwise. 3693@item arg=@var{str1},arg=@var{str2},... 3694Allows the user to pass input arguments, and can be used multiple times to build 3695up a list. The old-style @code{-kernel}/@code{-append} method of passing a 3696command line is still supported for backward compatibility. If both the 3697@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are 3698specified, the former is passed to semihosting as it always takes precedence. 3699@end table 3700ETEXI 3701DEF("old-param", 0, QEMU_OPTION_old_param, 3702 "-old-param old param mode\n", QEMU_ARCH_ARM) 3703STEXI 3704@item -old-param 3705@findex -old-param (ARM) 3706Old param mode (ARM only). 3707ETEXI 3708 3709DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ 3710 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n", 3711 QEMU_ARCH_ALL) 3712STEXI 3713@item -sandbox @var{arg} 3714@findex -sandbox 3715Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will 3716disable it. The default is 'off'. 3717ETEXI 3718 3719DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, 3720 "-readconfig <file>\n", QEMU_ARCH_ALL) 3721STEXI 3722@item -readconfig @var{file} 3723@findex -readconfig 3724Read device configuration from @var{file}. This approach is useful when you want to spawn 3725QEMU process with many command line options but you don't want to exceed the command line 3726character limit. 3727ETEXI 3728DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig, 3729 "-writeconfig <file>\n" 3730 " read/write config file\n", QEMU_ARCH_ALL) 3731STEXI 3732@item -writeconfig @var{file} 3733@findex -writeconfig 3734Write device configuration to @var{file}. The @var{file} can be either filename to save 3735command line and device configuration into file or dash @code{-}) character to print the 3736output to stdout. This can be later used as input file for @code{-readconfig} option. 3737ETEXI 3738DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, 3739 "-nodefconfig\n" 3740 " do not load default config files at startup\n", 3741 QEMU_ARCH_ALL) 3742STEXI 3743@item -nodefconfig 3744@findex -nodefconfig 3745Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup. 3746The @code{-nodefconfig} option will prevent QEMU from loading any of those config files. 3747ETEXI 3748DEF("no-user-config", 0, QEMU_OPTION_nouserconfig, 3749 "-no-user-config\n" 3750 " do not load user-provided config files at startup\n", 3751 QEMU_ARCH_ALL) 3752STEXI 3753@item -no-user-config 3754@findex -no-user-config 3755The @code{-no-user-config} option makes QEMU not load any of the user-provided 3756config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config 3757files from @var{datadir}. 3758ETEXI 3759DEF("trace", HAS_ARG, QEMU_OPTION_trace, 3760 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 3761 " specify tracing options\n", 3762 QEMU_ARCH_ALL) 3763STEXI 3764HXCOMM This line is not accurate, as some sub-options are backend-specific but 3765HXCOMM HX does not support conditional compilation of text. 3766@item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}] 3767@findex -trace 3768@include qemu-option-trace.texi 3769ETEXI 3770 3771HXCOMM Internal use 3772DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL) 3773DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL) 3774 3775#ifdef __linux__ 3776DEF("enable-fips", 0, QEMU_OPTION_enablefips, 3777 "-enable-fips enable FIPS 140-2 compliance\n", 3778 QEMU_ARCH_ALL) 3779#endif 3780STEXI 3781@item -enable-fips 3782@findex -enable-fips 3783Enable FIPS 140-2 compliance mode. 3784ETEXI 3785 3786HXCOMM Deprecated by -machine accel=tcg property 3787DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386) 3788 3789HXCOMM Deprecated by kvm-pit driver properties 3790DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection, 3791 "", QEMU_ARCH_I386) 3792 3793HXCOMM Deprecated (ignored) 3794DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386) 3795 3796HXCOMM Deprecated by -machine kernel_irqchip=on|off property 3797DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386) 3798 3799HXCOMM Deprecated (ignored) 3800DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL) 3801 3802DEF("msg", HAS_ARG, QEMU_OPTION_msg, 3803 "-msg timestamp[=on|off]\n" 3804 " change the format of messages\n" 3805 " on|off controls leading timestamps (default:on)\n", 3806 QEMU_ARCH_ALL) 3807STEXI 3808@item -msg timestamp[=on|off] 3809@findex -msg 3810prepend a timestamp to each log message.(default:on) 3811ETEXI 3812 3813DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate, 3814 "-dump-vmstate <file>\n" 3815 " Output vmstate information in JSON format to file.\n" 3816 " Use the scripts/vmstate-static-checker.py file to\n" 3817 " check for possible regressions in migration code\n" 3818 " by comparing two such vmstate dumps.\n", 3819 QEMU_ARCH_ALL) 3820STEXI 3821@item -dump-vmstate @var{file} 3822@findex -dump-vmstate 3823Dump json-encoded vmstate information for current machine type to file 3824in @var{file} 3825ETEXI 3826 3827STEXI 3828@end table 3829ETEXI 3830DEFHEADING() 3831DEFHEADING(Generic object creation) 3832STEXI 3833@table @option 3834ETEXI 3835 3836DEF("object", HAS_ARG, QEMU_OPTION_object, 3837 "-object TYPENAME[,PROP1=VALUE1,...]\n" 3838 " create a new object of type TYPENAME setting properties\n" 3839 " in the order they are specified. Note that the 'id'\n" 3840 " property must be set. These objects are placed in the\n" 3841 " '/objects' path.\n", 3842 QEMU_ARCH_ALL) 3843STEXI 3844@item -object @var{typename}[,@var{prop1}=@var{value1},...] 3845@findex -object 3846Create a new object of type @var{typename} setting properties 3847in the order they are specified. Note that the 'id' 3848property must be set. These objects are placed in the 3849'/objects' path. 3850 3851@table @option 3852 3853@item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off} 3854 3855Creates a memory file backend object, which can be used to back 3856the guest RAM with huge pages. The @option{id} parameter is a 3857unique ID that will be used to reference this memory region 3858when configuring the @option{-numa} argument. The @option{size} 3859option provides the size of the memory region, and accepts 3860common suffixes, eg @option{500M}. The @option{mem-path} provides 3861the path to either a shared memory or huge page filesystem mount. 3862The @option{share} boolean option determines whether the memory 3863region is marked as private to QEMU, or shared. The latter allows 3864a co-operating external process to access the QEMU memory region. 3865 3866@item -object rng-random,id=@var{id},filename=@var{/dev/random} 3867 3868Creates a random number generator backend which obtains entropy from 3869a device on the host. The @option{id} parameter is a unique ID that 3870will be used to reference this entropy backend from the @option{virtio-rng} 3871device. The @option{filename} parameter specifies which file to obtain 3872entropy from and if omitted defaults to @option{/dev/random}. 3873 3874@item -object rng-egd,id=@var{id},chardev=@var{chardevid} 3875 3876Creates a random number generator backend which obtains entropy from 3877an external daemon running on the host. The @option{id} parameter is 3878a unique ID that will be used to reference this entropy backend from 3879the @option{virtio-rng} device. The @option{chardev} parameter is 3880the unique ID of a character device backend that provides the connection 3881to the RNG daemon. 3882 3883@item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off} 3884 3885Creates a TLS anonymous credentials object, which can be used to provide 3886TLS support on network backends. The @option{id} parameter is a unique 3887ID which network backends will use to access the credentials. The 3888@option{endpoint} is either @option{server} or @option{client} depending 3889on whether the QEMU network backend that uses the credentials will be 3890acting as a client or as a server. If @option{verify-peer} is enabled 3891(the default) then once the handshake is completed, the peer credentials 3892will be verified, though this is a no-op for anonymous credentials. 3893 3894The @var{dir} parameter tells QEMU where to find the credential 3895files. For server endpoints, this directory may contain a file 3896@var{dh-params.pem} providing diffie-hellman parameters to use 3897for the TLS server. If the file is missing, QEMU will generate 3898a set of DH parameters at startup. This is a computationally 3899expensive operation that consumes random pool entropy, so it is 3900recommended that a persistent set of parameters be generated 3901upfront and saved. 3902 3903@item -object tls-creds-x509,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off},passwordid=@var{id} 3904 3905Creates a TLS anonymous credentials object, which can be used to provide 3906TLS support on network backends. The @option{id} parameter is a unique 3907ID which network backends will use to access the credentials. The 3908@option{endpoint} is either @option{server} or @option{client} depending 3909on whether the QEMU network backend that uses the credentials will be 3910acting as a client or as a server. If @option{verify-peer} is enabled 3911(the default) then once the handshake is completed, the peer credentials 3912will be verified. With x509 certificates, this implies that the clients 3913must be provided with valid client certificates too. 3914 3915The @var{dir} parameter tells QEMU where to find the credential 3916files. For server endpoints, this directory may contain a file 3917@var{dh-params.pem} providing diffie-hellman parameters to use 3918for the TLS server. If the file is missing, QEMU will generate 3919a set of DH parameters at startup. This is a computationally 3920expensive operation that consumes random pool entropy, so it is 3921recommended that a persistent set of parameters be generated 3922upfront and saved. 3923 3924For x509 certificate credentials the directory will contain further files 3925providing the x509 certificates. The certificates must be stored 3926in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional), 3927@var{server-cert.pem} (only servers), @var{server-key.pem} (only servers), 3928@var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients). 3929 3930For the @var{server-key.pem} and @var{client-key.pem} files which 3931contain sensitive private keys, it is possible to use an encrypted 3932version by providing the @var{passwordid} parameter. This provides 3933the ID of a previously created @code{secret} object containing the 3934password for decryption. 3935 3936@item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}] 3937 3938Interval @var{t} can't be 0, this filter batches the packet delivery: all 3939packets arriving in a given interval on netdev @var{netdevid} are delayed 3940until the end of the interval. Interval is in microseconds. 3941@option{status} is optional that indicate whether the netfilter is 3942on (enabled) or off (disabled), the default status for netfilter will be 'on'. 3943 3944queue @var{all|rx|tx} is an option that can be applied to any netfilter. 3945 3946@option{all}: the filter is attached both to the receive and the transmit 3947 queue of the netdev (default). 3948 3949@option{rx}: the filter is attached to the receive queue of the netdev, 3950 where it will receive packets sent to the netdev. 3951 3952@option{tx}: the filter is attached to the transmit queue of the netdev, 3953 where it will receive packets sent by the netdev. 3954 3955@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid}[,queue=@var{all|rx|tx}] 3956 3957filter-mirror on netdev @var{netdevid},mirror net packet to chardev 3958@var{chardevid} 3959 3960@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid}, 3961outdev=@var{chardevid}[,queue=@var{all|rx|tx}] 3962 3963filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev 3964@var{chardevid},and redirect indev's packet to filter. 3965Create a filter-redirector we need to differ outdev id from indev id, id can not 3966be the same. we can just use indev or outdev, but at least one of indev or outdev 3967need to be specified. 3968 3969@item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},rewriter-mode=@var{mode}[,queue=@var{all|rx|tx}] 3970 3971Filter-rewriter is a part of COLO project.It will rewrite tcp packet to 3972secondary from primary to keep secondary tcp connection,and rewrite 3973tcp packet to primary from secondary make tcp packet can be handled by 3974client. 3975 3976usage: 3977colo secondary: 3978-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 3979-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 3980-object filter-rewriter,id=rew0,netdev=hn0,queue=all 3981 3982@item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}] 3983 3984Dump the network traffic on netdev @var{dev} to the file specified by 3985@var{filename}. At most @var{len} bytes (64k by default) per packet are stored. 3986The file format is libpcap, so it can be analyzed with tools such as tcpdump 3987or Wireshark. 3988 3989@item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid}, 3990outdev=@var{chardevid} 3991 3992Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with 3993secondary packet. If the packets are same, we will output primary 3994packet to outdev@var{chardevid}, else we will notify colo-frame 3995do checkpoint and send primary packet to outdev@var{chardevid}. 3996 3997we must use it with the help of filter-mirror and filter-redirector. 3998 3999@example 4000 4001primary: 4002-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown 4003-device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66 4004-chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait 4005-chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait 4006-chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait 4007-chardev socket,id=compare0-0,host=3.3.3.3,port=9001 4008-chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait 4009-chardev socket,id=compare_out0,host=3.3.3.3,port=9005 4010-object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0 4011-object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out 4012-object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0 4013-object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0 4014 4015secondary: 4016-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown 4017-device e1000,netdev=hn0,mac=52:a4:00:12:78:66 4018-chardev socket,id=red0,host=3.3.3.3,port=9003 4019-chardev socket,id=red1,host=3.3.3.3,port=9004 4020-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4021-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4022 4023@end example 4024 4025If you want to know the detail of above command line, you can read 4026the colo-compare git log. 4027 4028@item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}] 4029 4030Creates a cryptodev backend which executes crypto opreation from 4031the QEMU cipher APIS. The @var{id} parameter is 4032a unique ID that will be used to reference this cryptodev backend from 4033the @option{virtio-crypto} device. The @var{queues} parameter is optional, 4034which specify the queue number of cryptodev backend, the default of 4035@var{queues} is 1. 4036 4037@example 4038 4039 # qemu-system-x86_64 \ 4040 [...] \ 4041 -object cryptodev-backend-builtin,id=cryptodev0 \ 4042 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4043 [...] 4044@end example 4045 4046@item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4047@item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4048 4049Defines a secret to store a password, encryption key, or some other sensitive 4050data. The sensitive data can either be passed directly via the @var{data} 4051parameter, or indirectly via the @var{file} parameter. Using the @var{data} 4052parameter is insecure unless the sensitive data is encrypted. 4053 4054The sensitive data can be provided in raw format (the default), or base64. 4055When encoded as JSON, the raw format only supports valid UTF-8 characters, 4056so base64 is recommended for sending binary data. QEMU will convert from 4057which ever format is provided to the format it needs internally. eg, an 4058RBD password can be provided in raw format, even though it will be base64 4059encoded when passed onto the RBD sever. 4060 4061For added protection, it is possible to encrypt the data associated with 4062a secret using the AES-256-CBC cipher. Use of encryption is indicated 4063by providing the @var{keyid} and @var{iv} parameters. The @var{keyid} 4064parameter provides the ID of a previously defined secret that contains 4065the AES-256 decryption key. This key should be 32-bytes long and be 4066base64 encoded. The @var{iv} parameter provides the random initialization 4067vector used for encryption of this particular secret and should be a 4068base64 encrypted string of the 16-byte IV. 4069 4070The simplest (insecure) usage is to provide the secret inline 4071 4072@example 4073 4074 # $QEMU -object secret,id=sec0,data=letmein,format=raw 4075 4076@end example 4077 4078The simplest secure usage is to provide the secret via a file 4079 4080 # echo -n "letmein" > mypasswd.txt 4081 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw 4082 4083For greater security, AES-256-CBC should be used. To illustrate usage, 4084consider the openssl command line tool which can encrypt the data. Note 4085that when encrypting, the plaintext must be padded to the cipher block 4086size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm. 4087 4088First a master key needs to be created in base64 encoding: 4089 4090@example 4091 # openssl rand -base64 32 > key.b64 4092 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"') 4093@end example 4094 4095Each secret to be encrypted needs to have a random initialization vector 4096generated. These do not need to be kept secret 4097 4098@example 4099 # openssl rand -base64 16 > iv.b64 4100 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"') 4101@end example 4102 4103The secret to be defined can now be encrypted, in this case we're 4104telling openssl to base64 encode the result, but it could be left 4105as raw bytes if desired. 4106 4107@example 4108 # SECRET=$(echo -n "letmein" | 4109 openssl enc -aes-256-cbc -a -K $KEY -iv $IV) 4110@end example 4111 4112When launching QEMU, create a master secret pointing to @code{key.b64} 4113and specify that to be used to decrypt the user password. Pass the 4114contents of @code{iv.b64} to the second secret 4115 4116@example 4117 # $QEMU \ 4118 -object secret,id=secmaster0,format=base64,file=key.b64 \ 4119 -object secret,id=sec0,keyid=secmaster0,format=base64,\ 4120 data=$SECRET,iv=$(<iv.b64) 4121@end example 4122 4123@end table 4124 4125ETEXI 4126 4127 4128HXCOMM This is the last statement. Insert new options before this line! 4129STEXI 4130@end table 4131ETEXI 4132
