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, hax or 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 " s390-squash-mcss=on|off controls support for squashing into default css (default=off)\n", 47 QEMU_ARCH_ALL) 48STEXI 49@item -machine [type=]@var{name}[,prop=@var{value}[,...]] 50@findex -machine 51Select the emulated machine by @var{name}. Use @code{-machine help} to list 52available machines. Supported machine properties are: 53@table @option 54@item accel=@var{accels1}[:@var{accels2}[:...]] 55This is used to enable an accelerator. Depending on the target architecture, 56kvm, xen, hax or tcg can be available. By default, tcg is used. If there is 57more than one accelerator specified, the next one is used if the previous one 58fails to initialize. 59@item kernel_irqchip=on|off 60Controls in-kernel irqchip support for the chosen accelerator when available. 61@item gfx_passthru=on|off 62Enables IGD GFX passthrough support for the chosen machine when available. 63@item vmport=on|off|auto 64Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the 65value based on accel. For accel=xen the default is off otherwise the default 66is on. 67@item kvm_shadow_mem=size 68Defines the size of the KVM shadow MMU. 69@item dump-guest-core=on|off 70Include guest memory in a core dump. The default is on. 71@item mem-merge=on|off 72Enables or disables memory merge support. This feature, when supported by 73the host, de-duplicates identical memory pages among VMs instances 74(enabled by default). 75@item aes-key-wrap=on|off 76Enables or disables AES key wrapping support on s390-ccw hosts. This feature 77controls whether AES wrapping keys will be created to allow 78execution of AES cryptographic functions. The default is on. 79@item dea-key-wrap=on|off 80Enables or disables DEA key wrapping support on s390-ccw hosts. This feature 81controls whether DEA wrapping keys will be created to allow 82execution of DEA cryptographic functions. The default is on. 83@item nvdimm=on|off 84Enables or disables NVDIMM support. The default is off. 85@item s390-squash-mcss=on|off 86Enables or disables squashing subchannels into the default css. 87The default is off. 88@end table 89ETEXI 90 91HXCOMM Deprecated by -machine 92DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL) 93 94DEF("cpu", HAS_ARG, QEMU_OPTION_cpu, 95 "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL) 96STEXI 97@item -cpu @var{model} 98@findex -cpu 99Select CPU model (@code{-cpu help} for list and additional feature selection) 100ETEXI 101 102DEF("accel", HAS_ARG, QEMU_OPTION_accel, 103 "-accel [accel=]accelerator[,thread=single|multi]\n" 104 " select accelerator (kvm, xen, hax or tcg; use 'help' for a list)\n" 105 " thread=single|multi (enable multi-threaded TCG)\n", QEMU_ARCH_ALL) 106STEXI 107@item -accel @var{name}[,prop=@var{value}[,...]] 108@findex -accel 109This is used to enable an accelerator. Depending on the target architecture, 110kvm, xen, hax or tcg can be available. By default, tcg is used. If there is 111more than one accelerator specified, the next one is used if the previous one 112fails to initialize. 113@table @option 114@item thread=single|multi 115Controls number of TCG threads. When the TCG is multi-threaded there will be one 116thread per vCPU therefor taking advantage of additional host cores. The default 117is to enable multi-threading where both the back-end and front-ends support it and 118no incompatible TCG features have been enabled (e.g. icount/replay). 119@end table 120ETEXI 121 122DEF("smp", HAS_ARG, QEMU_OPTION_smp, 123 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n" 124 " set the number of CPUs to 'n' [default=1]\n" 125 " maxcpus= maximum number of total cpus, including\n" 126 " offline CPUs for hotplug, etc\n" 127 " cores= number of CPU cores on one socket\n" 128 " threads= number of threads on one CPU core\n" 129 " sockets= number of discrete sockets in the system\n", 130 QEMU_ARCH_ALL) 131STEXI 132@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}] 133@findex -smp 134Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255 135CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs 136to 4. 137For the PC target, the number of @var{cores} per socket, the number 138of @var{threads} per cores and the total number of @var{sockets} can be 139specified. Missing values will be computed. If any on the three values is 140given, the total number of CPUs @var{n} can be omitted. @var{maxcpus} 141specifies the maximum number of hotpluggable CPUs. 142ETEXI 143 144DEF("numa", HAS_ARG, QEMU_OPTION_numa, 145 "-numa node[,mem=size][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n" 146 "-numa node[,memdev=id][,cpus=firstcpu[-lastcpu]][,nodeid=node]\n" 147 "-numa dist,src=source,dst=destination,val=distance\n", QEMU_ARCH_ALL) 148STEXI 149@item -numa node[,mem=@var{size}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}] 150@itemx -numa node[,memdev=@var{id}][,cpus=@var{firstcpu}[-@var{lastcpu}]][,nodeid=@var{node}] 151@itemx -numa dist,src=@var{source},dst=@var{destination},val=@var{distance} 152@itemx -numa cpu,node-id=@var{node}[,socket-id=@var{x}][,core-id=@var{y}][,thread-id=@var{z}] 153@findex -numa 154Define a NUMA node and assign RAM and VCPUs to it. 155Set the NUMA distance from a source node to a destination node. 156 157Legacy VCPU assignment uses @samp{cpus} option where 158@var{firstcpu} and @var{lastcpu} are CPU indexes. Each 159@samp{cpus} option represent a contiguous range of CPU indexes 160(or a single VCPU if @var{lastcpu} is omitted). A non-contiguous 161set of VCPUs can be represented by providing multiple @samp{cpus} 162options. If @samp{cpus} is omitted on all nodes, VCPUs are automatically 163split between them. 164 165For example, the following option assigns VCPUs 0, 1, 2 and 5 to 166a NUMA node: 167@example 168-numa node,cpus=0-2,cpus=5 169@end example 170 171@samp{cpu} option is a new alternative to @samp{cpus} option 172which uses @samp{socket-id|core-id|thread-id} properties to assign 173CPU objects to a @var{node} using topology layout properties of CPU. 174The set of properties is machine specific, and depends on used 175machine type/@samp{smp} options. It could be queried with 176@samp{hotpluggable-cpus} monitor command. 177@samp{node-id} property specifies @var{node} to which CPU object 178will be assigned, it's required for @var{node} to be declared 179with @samp{node} option before it's used with @samp{cpu} option. 180 181For example: 182@example 183-M pc \ 184-smp 1,sockets=2,maxcpus=2 \ 185-numa node,nodeid=0 -numa node,nodeid=1 \ 186-numa cpu,node-id=0,socket-id=0 -numa cpu,node-id=1,socket-id=1 187@end example 188 189@samp{mem} assigns a given RAM amount to a node. @samp{memdev} 190assigns RAM from a given memory backend device to a node. If 191@samp{mem} and @samp{memdev} are omitted in all nodes, RAM is 192split equally between them. 193 194@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, 195if one node uses @samp{memdev}, all of them have to use it. 196 197@var{source} and @var{destination} are NUMA node IDs. 198@var{distance} is the NUMA distance from @var{source} to @var{destination}. 199The distance from a node to itself is always 10. If any pair of nodes is 200given a distance, then all pairs must be given distances. Although, when 201distances are only given in one direction for each pair of nodes, then 202the distances in the opposite directions are assumed to be the same. If, 203however, an asymmetrical pair of distances is given for even one node 204pair, then all node pairs must be provided distance values for both 205directions, even when they are symmetrical. When a node is unreachable 206from another node, set the pair's distance to 255. 207 208Note that the -@option{numa} option doesn't allocate any of the 209specified resources, it just assigns existing resources to NUMA 210nodes. This means that one still has to use the @option{-m}, 211@option{-smp} options to allocate RAM and VCPUs respectively. 212 213ETEXI 214 215DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd, 216 "-add-fd fd=fd,set=set[,opaque=opaque]\n" 217 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL) 218STEXI 219@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}] 220@findex -add-fd 221 222Add a file descriptor to an fd set. Valid options are: 223 224@table @option 225@item fd=@var{fd} 226This option defines the file descriptor of which a duplicate is added to fd set. 227The file descriptor cannot be stdin, stdout, or stderr. 228@item set=@var{set} 229This option defines the ID of the fd set to add the file descriptor to. 230@item opaque=@var{opaque} 231This option defines a free-form string that can be used to describe @var{fd}. 232@end table 233 234You can open an image using pre-opened file descriptors from an fd set: 235@example 236qemu-system-i386 237-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 238-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 239-drive file=/dev/fdset/2,index=0,media=disk 240@end example 241ETEXI 242 243DEF("set", HAS_ARG, QEMU_OPTION_set, 244 "-set group.id.arg=value\n" 245 " set <arg> parameter for item <id> of type <group>\n" 246 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL) 247STEXI 248@item -set @var{group}.@var{id}.@var{arg}=@var{value} 249@findex -set 250Set parameter @var{arg} for item @var{id} of type @var{group} 251ETEXI 252 253DEF("global", HAS_ARG, QEMU_OPTION_global, 254 "-global driver.property=value\n" 255 "-global driver=driver,property=property,value=value\n" 256 " set a global default for a driver property\n", 257 QEMU_ARCH_ALL) 258STEXI 259@item -global @var{driver}.@var{prop}=@var{value} 260@itemx -global driver=@var{driver},property=@var{property},value=@var{value} 261@findex -global 262Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.: 263 264@example 265qemu-system-i386 -global ide-hd.physical_block_size=4096 disk-image.img 266@end example 267 268In particular, you can use this to set driver properties for devices which are 269created automatically by the machine model. To create a device which is not 270created automatically and set properties on it, use -@option{device}. 271 272-global @var{driver}.@var{prop}=@var{value} is shorthand for -global 273driver=@var{driver},property=@var{prop},value=@var{value}. The 274longhand syntax works even when @var{driver} contains a dot. 275ETEXI 276 277DEF("boot", HAS_ARG, QEMU_OPTION_boot, 278 "-boot [order=drives][,once=drives][,menu=on|off]\n" 279 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n" 280 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n" 281 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n" 282 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n" 283 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n", 284 QEMU_ARCH_ALL) 285STEXI 286@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] 287@findex -boot 288Specify boot order @var{drives} as a string of drive letters. Valid 289drive letters depend on the target architecture. The x86 PC uses: a, b 290(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot 291from network adapter 1-4), hard disk boot is the default. To apply a 292particular boot order only on the first startup, specify it via 293@option{once}. Note that the @option{order} or @option{once} parameter 294should not be used together with the @option{bootindex} property of 295devices, since the firmware implementations normally do not support both 296at the same time. 297 298Interactive boot menus/prompts can be enabled via @option{menu=on} as far 299as firmware/BIOS supports them. The default is non-interactive boot. 300 301A splash picture could be passed to bios, enabling user to show it as logo, 302when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS 303supports them. Currently Seabios for X86 system support it. 304limitation: The splash file could be a jpeg file or a BMP file in 24 BPP 305format(true color). The resolution should be supported by the SVGA mode, so 306the recommended is 320x240, 640x480, 800x640. 307 308A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms 309when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not 310reboot, qemu passes '-1' to bios by default. Currently Seabios for X86 311system support it. 312 313Do strict boot via @option{strict=on} as far as firmware/BIOS 314supports it. This only effects when boot priority is changed by 315bootindex options. The default is non-strict boot. 316 317@example 318# try to boot from network first, then from hard disk 319qemu-system-i386 -boot order=nc 320# boot from CD-ROM first, switch back to default order after reboot 321qemu-system-i386 -boot once=d 322# boot with a splash picture for 5 seconds. 323qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000 324@end example 325 326Note: The legacy format '-boot @var{drives}' is still supported but its 327use is discouraged as it may be removed from future versions. 328ETEXI 329 330DEF("m", HAS_ARG, QEMU_OPTION_m, 331 "-m [size=]megs[,slots=n,maxmem=size]\n" 332 " configure guest RAM\n" 333 " size: initial amount of guest memory\n" 334 " slots: number of hotplug slots (default: none)\n" 335 " maxmem: maximum amount of guest memory (default: none)\n" 336 "NOTE: Some architectures might enforce a specific granularity\n", 337 QEMU_ARCH_ALL) 338STEXI 339@item -m [size=]@var{megs}[,slots=n,maxmem=size] 340@findex -m 341Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB. 342Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in 343megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem} 344could be used to set amount of hotpluggable memory slots and maximum amount of 345memory. Note that @var{maxmem} must be aligned to the page size. 346 347For example, the following command-line sets the guest startup RAM size to 3481GB, creates 3 slots to hotplug additional memory and sets the maximum 349memory the guest can reach to 4GB: 350 351@example 352qemu-system-x86_64 -m 1G,slots=3,maxmem=4G 353@end example 354 355If @var{slots} and @var{maxmem} are not specified, memory hotplug won't 356be enabled and the guest startup RAM will never increase. 357ETEXI 358 359DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath, 360 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL) 361STEXI 362@item -mem-path @var{path} 363@findex -mem-path 364Allocate guest RAM from a temporarily created file in @var{path}. 365ETEXI 366 367DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc, 368 "-mem-prealloc preallocate guest memory (use with -mem-path)\n", 369 QEMU_ARCH_ALL) 370STEXI 371@item -mem-prealloc 372@findex -mem-prealloc 373Preallocate memory when using -mem-path. 374ETEXI 375 376DEF("k", HAS_ARG, QEMU_OPTION_k, 377 "-k language use keyboard layout (for example 'fr' for French)\n", 378 QEMU_ARCH_ALL) 379STEXI 380@item -k @var{language} 381@findex -k 382Use keyboard layout @var{language} (for example @code{fr} for 383French). This option is only needed where it is not easy to get raw PC 384keycodes (e.g. on Macs, with some X11 servers or with a VNC or curses 385display). You don't normally need to use it on PC/Linux or PC/Windows 386hosts. 387 388The available layouts are: 389@example 390ar de-ch es fo fr-ca hu ja mk no pt-br sv 391da en-gb et fr fr-ch is lt nl pl ru th 392de en-us fi fr-be hr it lv nl-be pt sl tr 393@end example 394 395The default is @code{en-us}. 396ETEXI 397 398 399DEF("audio-help", 0, QEMU_OPTION_audio_help, 400 "-audio-help print list of audio drivers and their options\n", 401 QEMU_ARCH_ALL) 402STEXI 403@item -audio-help 404@findex -audio-help 405Will show the audio subsystem help: list of drivers, tunable 406parameters. 407ETEXI 408 409DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw, 410 "-soundhw c1,... enable audio support\n" 411 " and only specified sound cards (comma separated list)\n" 412 " use '-soundhw help' to get the list of supported cards\n" 413 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL) 414STEXI 415@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all 416@findex -soundhw 417Enable audio and selected sound hardware. Use 'help' to print all 418available sound hardware. 419 420@example 421qemu-system-i386 -soundhw sb16,adlib disk.img 422qemu-system-i386 -soundhw es1370 disk.img 423qemu-system-i386 -soundhw ac97 disk.img 424qemu-system-i386 -soundhw hda disk.img 425qemu-system-i386 -soundhw all disk.img 426qemu-system-i386 -soundhw help 427@end example 428 429Note that Linux's i810_audio OSS kernel (for AC97) module might 430require manually specifying clocking. 431 432@example 433modprobe i810_audio clocking=48000 434@end example 435ETEXI 436 437DEF("balloon", HAS_ARG, QEMU_OPTION_balloon, 438 "-balloon none disable balloon device\n" 439 "-balloon virtio[,addr=str]\n" 440 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL) 441STEXI 442@item -balloon none 443@findex -balloon 444Disable balloon device. 445@item -balloon virtio[,addr=@var{addr}] 446Enable virtio balloon device (default), optionally with PCI address 447@var{addr}. 448ETEXI 449 450DEF("device", HAS_ARG, QEMU_OPTION_device, 451 "-device driver[,prop[=value][,...]]\n" 452 " add device (based on driver)\n" 453 " prop=value,... sets driver properties\n" 454 " use '-device help' to print all possible drivers\n" 455 " use '-device driver,help' to print all possible properties\n", 456 QEMU_ARCH_ALL) 457STEXI 458@item -device @var{driver}[,@var{prop}[=@var{value}][,...]] 459@findex -device 460Add device @var{driver}. @var{prop}=@var{value} sets driver 461properties. Valid properties depend on the driver. To get help on 462possible drivers and properties, use @code{-device help} and 463@code{-device @var{driver},help}. 464 465Some drivers are: 466@item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}][,sdrfile=@var{file}][,furareasize=@var{val}][,furdatafile=@var{file}] 467 468Add an IPMI BMC. This is a simulation of a hardware management 469interface processor that normally sits on a system. It provides 470a watchdog and the ability to reset and power control the system. 471You need to connect this to an IPMI interface to make it useful 472 473The IPMI slave address to use for the BMC. The default is 0x20. 474This address is the BMC's address on the I2C network of management 475controllers. If you don't know what this means, it is safe to ignore 476it. 477 478@table @option 479@item bmc=@var{id} 480The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above. 481@item slave_addr=@var{val} 482Define slave address to use for the BMC. The default is 0x20. 483@item sdrfile=@var{file} 484file containing raw Sensor Data Records (SDR) data. The default is none. 485@item fruareasize=@var{val} 486size of a Field Replaceable Unit (FRU) area. The default is 1024. 487@item frudatafile=@var{file} 488file containing raw Field Replaceable Unit (FRU) inventory data. The default is none. 489@end table 490 491@item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}] 492 493Add a connection to an external IPMI BMC simulator. Instead of 494locally emulating the BMC like the above item, instead connect 495to an external entity that provides the IPMI services. 496 497A connection is made to an external BMC simulator. If you do this, it 498is strongly recommended that you use the "reconnect=" chardev option 499to reconnect to the simulator if the connection is lost. Note that if 500this is not used carefully, it can be a security issue, as the 501interface has the ability to send resets, NMIs, and power off the VM. 502It's best if QEMU makes a connection to an external simulator running 503on a secure port on localhost, so neither the simulator nor QEMU is 504exposed to any outside network. 505 506See the "lanserv/README.vm" file in the OpenIPMI library for more 507details on the external interface. 508 509@item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 510 511Add a KCS IPMI interafce on the ISA bus. This also adds a 512corresponding ACPI and SMBIOS entries, if appropriate. 513 514@table @option 515@item bmc=@var{id} 516The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above. 517@item ioport=@var{val} 518Define the I/O address of the interface. The default is 0xca0 for KCS. 519@item irq=@var{val} 520Define the interrupt to use. The default is 5. To disable interrupts, 521set this to 0. 522@end table 523 524@item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 525 526Like the KCS interface, but defines a BT interface. The default port is 5270xe4 and the default interrupt is 5. 528 529ETEXI 530 531DEF("name", HAS_ARG, QEMU_OPTION_name, 532 "-name string1[,process=string2][,debug-threads=on|off]\n" 533 " set the name of the guest\n" 534 " string1 sets the window title and string2 the process name (on Linux)\n" 535 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n" 536 " NOTE: The thread names are for debugging and not a stable API.\n", 537 QEMU_ARCH_ALL) 538STEXI 539@item -name @var{name} 540@findex -name 541Sets the @var{name} of the guest. 542This name will be displayed in the SDL window caption. 543The @var{name} will also be used for the VNC server. 544Also optionally set the top visible process name in Linux. 545Naming of individual threads can also be enabled on Linux to aid debugging. 546ETEXI 547 548DEF("uuid", HAS_ARG, QEMU_OPTION_uuid, 549 "-uuid %08x-%04x-%04x-%04x-%012x\n" 550 " specify machine UUID\n", QEMU_ARCH_ALL) 551STEXI 552@item -uuid @var{uuid} 553@findex -uuid 554Set system UUID. 555ETEXI 556 557STEXI 558@end table 559ETEXI 560DEFHEADING() 561 562DEFHEADING(Block device options) 563STEXI 564@table @option 565ETEXI 566 567DEF("fda", HAS_ARG, QEMU_OPTION_fda, 568 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL) 569DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL) 570STEXI 571@item -fda @var{file} 572@itemx -fdb @var{file} 573@findex -fda 574@findex -fdb 575Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). 576ETEXI 577 578DEF("hda", HAS_ARG, QEMU_OPTION_hda, 579 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL) 580DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL) 581DEF("hdc", HAS_ARG, QEMU_OPTION_hdc, 582 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL) 583DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL) 584STEXI 585@item -hda @var{file} 586@itemx -hdb @var{file} 587@itemx -hdc @var{file} 588@itemx -hdd @var{file} 589@findex -hda 590@findex -hdb 591@findex -hdc 592@findex -hdd 593Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}). 594ETEXI 595 596DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom, 597 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n", 598 QEMU_ARCH_ALL) 599STEXI 600@item -cdrom @var{file} 601@findex -cdrom 602Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and 603@option{-cdrom} at the same time). You can use the host CD-ROM by 604using @file{/dev/cdrom} as filename (@pxref{host_drives}). 605ETEXI 606 607DEF("blockdev", HAS_ARG, QEMU_OPTION_blockdev, 608 "-blockdev [driver=]driver[,node-name=N][,discard=ignore|unmap]\n" 609 " [,cache.direct=on|off][,cache.no-flush=on|off]\n" 610 " [,read-only=on|off][,detect-zeroes=on|off|unmap]\n" 611 " [,driver specific parameters...]\n" 612 " configure a block backend\n", QEMU_ARCH_ALL) 613STEXI 614@item -blockdev @var{option}[,@var{option}[,@var{option}[,...]]] 615@findex -blockdev 616 617Define a new block driver node. Some of the options apply to all block drivers, 618other options are only accepted for a specific block driver. See below for a 619list of generic options and options for the most common block drivers. 620 621Options that expect a reference to another node (e.g. @code{file}) can be 622given in two ways. Either you specify the node name of an already existing node 623(file=@var{node-name}), or you define a new node inline, adding options 624for the referenced node after a dot (file.filename=@var{path},file.aio=native). 625 626A block driver node created with @option{-blockdev} can be used for a guest 627device by specifying its node name for the @code{drive} property in a 628@option{-device} argument that defines a block device. 629 630@table @option 631@item Valid options for any block driver node: 632 633@table @code 634@item driver 635Specifies the block driver to use for the given node. 636@item node-name 637This defines the name of the block driver node by which it will be referenced 638later. The name must be unique, i.e. it must not match the name of a different 639block driver node, or (if you use @option{-drive} as well) the ID of a drive. 640 641If no node name is specified, it is automatically generated. The generated node 642name is not intended to be predictable and changes between QEMU invocations. 643For the top level, an explicit node name must be specified. 644@item read-only 645Open the node read-only. Guest write attempts will fail. 646@item cache.direct 647The host page cache can be avoided with @option{cache.direct=on}. This will 648attempt to do disk IO directly to the guest's memory. QEMU may still perform an 649internal copy of the data. 650@item cache.no-flush 651In case you don't care about data integrity over host failures, you can use 652@option{cache.no-flush=on}. This option tells QEMU that it never needs to write 653any data to the disk but can instead keep things in cache. If anything goes 654wrong, like your host losing power, the disk storage getting disconnected 655accidentally, etc. your image will most probably be rendered unusable. 656@item discard=@var{discard} 657@var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls 658whether @code{discard} (also known as @code{trim} or @code{unmap}) requests are 659ignored or passed to the filesystem. Some machine types may not support 660discard requests. 661@item detect-zeroes=@var{detect-zeroes} 662@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic 663conversion of plain zero writes by the OS to driver specific optimized 664zero write commands. You may even choose "unmap" if @var{discard} is set 665to "unmap" to allow a zero write to be converted to an @code{unmap} operation. 666@end table 667 668@item Driver-specific options for @code{file} 669 670This is the protocol-level block driver for accessing regular files. 671 672@table @code 673@item filename 674The path to the image file in the local filesystem 675@item aio 676Specifies the AIO backend (threads/native, default: threads) 677@end table 678Example: 679@example 680-blockdev driver=file,node-name=disk,filename=disk.img 681@end example 682 683@item Driver-specific options for @code{raw} 684 685This is the image format block driver for raw images. It is usually 686stacked on top of a protocol level block driver such as @code{file}. 687 688@table @code 689@item file 690Reference to or definition of the data source block driver node 691(e.g. a @code{file} driver node) 692@end table 693Example 1: 694@example 695-blockdev driver=file,node-name=disk_file,filename=disk.img 696-blockdev driver=raw,node-name=disk,file=disk_file 697@end example 698Example 2: 699@example 700-blockdev driver=raw,node-name=disk,file.driver=file,file.filename=disk.img 701@end example 702 703@item Driver-specific options for @code{qcow2} 704 705This is the image format block driver for qcow2 images. It is usually 706stacked on top of a protocol level block driver such as @code{file}. 707 708@table @code 709@item file 710Reference to or definition of the data source block driver node 711(e.g. a @code{file} driver node) 712 713@item backing 714Reference to or definition of the backing file block device (default is taken 715from the image file). It is allowed to pass an empty string here in order to 716disable the default backing file. 717 718@item lazy-refcounts 719Whether to enable the lazy refcounts feature (on/off; default is taken from the 720image file) 721 722@item cache-size 723The maximum total size of the L2 table and refcount block caches in bytes 724(default: 1048576 bytes or 8 clusters, whichever is larger) 725 726@item l2-cache-size 727The maximum size of the L2 table cache in bytes 728(default: 4/5 of the total cache size) 729 730@item refcount-cache-size 731The maximum size of the refcount block cache in bytes 732(default: 1/5 of the total cache size) 733 734@item cache-clean-interval 735Clean unused entries in the L2 and refcount caches. The interval is in seconds. 736The default value is 0 and it disables this feature. 737 738@item pass-discard-request 739Whether discard requests to the qcow2 device should be forwarded to the data 740source (on/off; default: on if discard=unmap is specified, off otherwise) 741 742@item pass-discard-snapshot 743Whether discard requests for the data source should be issued when a snapshot 744operation (e.g. deleting a snapshot) frees clusters in the qcow2 file (on/off; 745default: on) 746 747@item pass-discard-other 748Whether discard requests for the data source should be issued on other 749occasions where a cluster gets freed (on/off; default: off) 750 751@item overlap-check 752Which overlap checks to perform for writes to the image 753(none/constant/cached/all; default: cached). For details or finer 754granularity control refer to the QAPI documentation of @code{blockdev-add}. 755@end table 756 757Example 1: 758@example 759-blockdev driver=file,node-name=my_file,filename=/tmp/disk.qcow2 760-blockdev driver=qcow2,node-name=hda,file=my_file,overlap-check=none,cache-size=16777216 761@end example 762Example 2: 763@example 764-blockdev driver=qcow2,node-name=disk,file.driver=http,file.filename=http://example.com/image.qcow2 765@end example 766 767@item Driver-specific options for other drivers 768Please refer to the QAPI documentation of the @code{blockdev-add} QMP command. 769 770@end table 771 772ETEXI 773 774DEF("drive", HAS_ARG, QEMU_OPTION_drive, 775 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" 776 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n" 777 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n" 778 " [,serial=s][,addr=A][,rerror=ignore|stop|report]\n" 779 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n" 780 " [,readonly=on|off][,copy-on-read=on|off]\n" 781 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n" 782 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n" 783 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n" 784 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n" 785 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n" 786 " [[,iops_size=is]]\n" 787 " [[,group=g]]\n" 788 " use 'file' as a drive image\n", QEMU_ARCH_ALL) 789STEXI 790@item -drive @var{option}[,@var{option}[,@var{option}[,...]]] 791@findex -drive 792 793Define a new drive. This includes creating a block driver node (the backend) as 794well as a guest device, and is mostly a shortcut for defining the corresponding 795@option{-blockdev} and @option{-device} options. 796 797@option{-drive} accepts all options that are accepted by @option{-blockdev}. In 798addition, it knows the following options: 799 800@table @option 801@item file=@var{file} 802This option defines which disk image (@pxref{disk_images}) to use with 803this drive. If the filename contains comma, you must double it 804(for instance, "file=my,,file" to use file "my,file"). 805 806Special files such as iSCSI devices can be specified using protocol 807specific URLs. See the section for "Device URL Syntax" for more information. 808@item if=@var{interface} 809This option defines on which type on interface the drive is connected. 810Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio, none. 811@item bus=@var{bus},unit=@var{unit} 812These options define where is connected the drive by defining the bus number and 813the unit id. 814@item index=@var{index} 815This option defines where is connected the drive by using an index in the list 816of available connectors of a given interface type. 817@item media=@var{media} 818This option defines the type of the media: disk or cdrom. 819@item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}] 820These options have the same definition as they have in @option{-hdachs}. 821These parameters are deprecated, use the corresponding parameters 822of @code{-device} instead. 823@item snapshot=@var{snapshot} 824@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive 825(see @option{-snapshot}). 826@item cache=@var{cache} 827@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" 828and controls how the host cache is used to access block data. This is a 829shortcut that sets the @option{cache.direct} and @option{cache.no-flush} 830options (as in @option{-blockdev}), and additionally @option{cache.writeback}, 831which provides a default for the @option{write-cache} option of block guest 832devices (as in @option{-device}). The modes correspond to the following 833settings: 834 835@c Our texi2pod.pl script doesn't support @multitable, so fall back to using 836@c plain ASCII art (well, UTF-8 art really). This looks okay both in the manpage 837@c and the HTML output. 838@example 839@ │ cache.writeback cache.direct cache.no-flush 840─────────────┼───────────────────────────────────────────────── 841writeback │ on off off 842none │ on on off 843writethrough │ off off off 844directsync │ off on off 845unsafe │ on off on 846@end example 847 848The default mode is @option{cache=writeback}. 849 850@item aio=@var{aio} 851@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO. 852@item format=@var{format} 853Specify which disk @var{format} will be used rather than detecting 854the format. Can be used to specify format=raw to avoid interpreting 855an untrusted format header. 856@item serial=@var{serial} 857This option specifies the serial number to assign to the device. This 858parameter is deprecated, use the corresponding parameter of @code{-device} 859instead. 860@item addr=@var{addr} 861Specify the controller's PCI address (if=virtio only). This parameter is 862deprecated, use the corresponding parameter of @code{-device} instead. 863@item werror=@var{action},rerror=@var{action} 864Specify which @var{action} to take on write and read errors. Valid actions are: 865"ignore" (ignore the error and try to continue), "stop" (pause QEMU), 866"report" (report the error to the guest), "enospc" (pause QEMU only if the 867host disk is full; report the error to the guest otherwise). 868The default setting is @option{werror=enospc} and @option{rerror=report}. 869@item copy-on-read=@var{copy-on-read} 870@var{copy-on-read} is "on" or "off" and enables whether to copy read backing 871file sectors into the image file. 872@item bps=@var{b},bps_rd=@var{r},bps_wr=@var{w} 873Specify bandwidth throttling limits in bytes per second, either for all request 874types or for reads or writes only. Small values can lead to timeouts or hangs 875inside the guest. A safe minimum for disks is 2 MB/s. 876@item bps_max=@var{bm},bps_rd_max=@var{rm},bps_wr_max=@var{wm} 877Specify bursts in bytes per second, either for all request types or for reads 878or writes only. Bursts allow the guest I/O to spike above the limit 879temporarily. 880@item iops=@var{i},iops_rd=@var{r},iops_wr=@var{w} 881Specify request rate limits in requests per second, either for all request 882types or for reads or writes only. 883@item iops_max=@var{bm},iops_rd_max=@var{rm},iops_wr_max=@var{wm} 884Specify bursts in requests per second, either for all request types or for reads 885or writes only. Bursts allow the guest I/O to spike above the limit 886temporarily. 887@item iops_size=@var{is} 888Let every @var{is} bytes of a request count as a new request for iops 889throttling purposes. Use this option to prevent guests from circumventing iops 890limits by sending fewer but larger requests. 891@item group=@var{g} 892Join a throttling quota group with given name @var{g}. All drives that are 893members of the same group are accounted for together. Use this option to 894prevent guests from circumventing throttling limits by using many small disks 895instead of a single larger disk. 896@end table 897 898By default, the @option{cache.writeback=on} mode is used. It will report data 899writes as completed as soon as the data is present in the host page cache. 900This is safe as long as your guest OS makes sure to correctly flush disk caches 901where needed. If your guest OS does not handle volatile disk write caches 902correctly and your host crashes or loses power, then the guest may experience 903data corruption. 904 905For such guests, you should consider using @option{cache.writeback=off}. This 906means that the host page cache will be used to read and write data, but write 907notification will be sent to the guest only after QEMU has made sure to flush 908each write to the disk. Be aware that this has a major impact on performance. 909 910When using the @option{-snapshot} option, unsafe caching is always used. 911 912Copy-on-read avoids accessing the same backing file sectors repeatedly and is 913useful when the backing file is over a slow network. By default copy-on-read 914is off. 915 916Instead of @option{-cdrom} you can use: 917@example 918qemu-system-i386 -drive file=file,index=2,media=cdrom 919@end example 920 921Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can 922use: 923@example 924qemu-system-i386 -drive file=file,index=0,media=disk 925qemu-system-i386 -drive file=file,index=1,media=disk 926qemu-system-i386 -drive file=file,index=2,media=disk 927qemu-system-i386 -drive file=file,index=3,media=disk 928@end example 929 930You can open an image using pre-opened file descriptors from an fd set: 931@example 932qemu-system-i386 933-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 934-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 935-drive file=/dev/fdset/2,index=0,media=disk 936@end example 937 938You can connect a CDROM to the slave of ide0: 939@example 940qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom 941@end example 942 943If you don't specify the "file=" argument, you define an empty drive: 944@example 945qemu-system-i386 -drive if=ide,index=1,media=cdrom 946@end example 947 948Instead of @option{-fda}, @option{-fdb}, you can use: 949@example 950qemu-system-i386 -drive file=file,index=0,if=floppy 951qemu-system-i386 -drive file=file,index=1,if=floppy 952@end example 953 954By default, @var{interface} is "ide" and @var{index} is automatically 955incremented: 956@example 957qemu-system-i386 -drive file=a -drive file=b" 958@end example 959is interpreted like: 960@example 961qemu-system-i386 -hda a -hdb b 962@end example 963ETEXI 964 965DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock, 966 "-mtdblock file use 'file' as on-board Flash memory image\n", 967 QEMU_ARCH_ALL) 968STEXI 969@item -mtdblock @var{file} 970@findex -mtdblock 971Use @var{file} as on-board Flash memory image. 972ETEXI 973 974DEF("sd", HAS_ARG, QEMU_OPTION_sd, 975 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL) 976STEXI 977@item -sd @var{file} 978@findex -sd 979Use @var{file} as SecureDigital card image. 980ETEXI 981 982DEF("pflash", HAS_ARG, QEMU_OPTION_pflash, 983 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL) 984STEXI 985@item -pflash @var{file} 986@findex -pflash 987Use @var{file} as a parallel flash image. 988ETEXI 989 990DEF("snapshot", 0, QEMU_OPTION_snapshot, 991 "-snapshot write to temporary files instead of disk image files\n", 992 QEMU_ARCH_ALL) 993STEXI 994@item -snapshot 995@findex -snapshot 996Write to temporary files instead of disk image files. In this case, 997the raw disk image you use is not written back. You can however force 998the write back by pressing @key{C-a s} (@pxref{disk_images}). 999ETEXI 1000 1001DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \ 1002 "-hdachs c,h,s[,t]\n" \ 1003 " force hard disk 0 physical geometry and the optional BIOS\n" \ 1004 " translation (t=none or lba) (usually QEMU can guess them)\n", 1005 QEMU_ARCH_ALL) 1006STEXI 1007@item -hdachs @var{c},@var{h},@var{s},[,@var{t}] 1008@findex -hdachs 1009Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <= 1010@var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS 1011translation mode (@var{t}=none, lba or auto). Usually QEMU can guess 1012all those parameters. This option is deprecated, please use 1013@code{-device ide-hd,cyls=c,heads=h,secs=s,...} instead. 1014ETEXI 1015 1016DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev, 1017 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n" 1018 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n" 1019 " [[,throttling.bps-total=b]|[[,throttling.bps-read=r][,throttling.bps-write=w]]]\n" 1020 " [[,throttling.iops-total=i]|[[,throttling.iops-read=r][,throttling.iops-write=w]]]\n" 1021 " [[,throttling.bps-total-max=bm]|[[,throttling.bps-read-max=rm][,throttling.bps-write-max=wm]]]\n" 1022 " [[,throttling.iops-total-max=im]|[[,throttling.iops-read-max=irm][,throttling.iops-write-max=iwm]]]\n" 1023 " [[,throttling.iops-size=is]]\n", 1024 QEMU_ARCH_ALL) 1025 1026STEXI 1027 1028@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}][,fmode=@var{fmode}][,dmode=@var{dmode}] 1029@findex -fsdev 1030Define a new file system device. Valid options are: 1031@table @option 1032@item @var{fsdriver} 1033This option specifies the fs driver backend to use. 1034Currently "local", "handle" and "proxy" file system drivers are supported. 1035@item id=@var{id} 1036Specifies identifier for this device 1037@item path=@var{path} 1038Specifies the export path for the file system device. Files under 1039this path will be available to the 9p client on the guest. 1040@item security_model=@var{security_model} 1041Specifies the security model to be used for this export path. 1042Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 1043In "passthrough" security model, files are stored using the same 1044credentials as they are created on the guest. This requires QEMU 1045to run as root. In "mapped-xattr" security model, some of the file 1046attributes like uid, gid, mode bits and link target are stored as 1047file attributes. For "mapped-file" these attributes are stored in the 1048hidden .virtfs_metadata directory. Directories exported by this security model cannot 1049interact with other unix tools. "none" security model is same as 1050passthrough except the sever won't report failures if it fails to 1051set file attributes like ownership. Security model is mandatory 1052only for local fsdriver. Other fsdrivers (like handle, proxy) don't take 1053security model as a parameter. 1054@item writeout=@var{writeout} 1055This is an optional argument. The only supported value is "immediate". 1056This means that host page cache will be used to read and write data but 1057write notification will be sent to the guest only when the data has been 1058reported as written by the storage subsystem. 1059@item readonly 1060Enables exporting 9p share as a readonly mount for guests. By default 1061read-write access is given. 1062@item socket=@var{socket} 1063Enables proxy filesystem driver to use passed socket file for communicating 1064with virtfs-proxy-helper 1065@item sock_fd=@var{sock_fd} 1066Enables proxy filesystem driver to use passed socket descriptor for 1067communicating with virtfs-proxy-helper. Usually a helper like libvirt 1068will create socketpair and pass one of the fds as sock_fd 1069@item fmode=@var{fmode} 1070Specifies the default mode for newly created files on the host. Works only 1071with security models "mapped-xattr" and "mapped-file". 1072@item dmode=@var{dmode} 1073Specifies the default mode for newly created directories on the host. Works 1074only with security models "mapped-xattr" and "mapped-file". 1075@end table 1076 1077-fsdev option is used along with -device driver "virtio-9p-pci". 1078@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag} 1079Options for virtio-9p-pci driver are: 1080@table @option 1081@item fsdev=@var{id} 1082Specifies the id value specified along with -fsdev option 1083@item mount_tag=@var{mount_tag} 1084Specifies the tag name to be used by the guest to mount this export point 1085@end table 1086 1087ETEXI 1088 1089DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs, 1090 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n" 1091 " [,id=id][,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd][,fmode=fmode][,dmode=dmode]\n", 1092 QEMU_ARCH_ALL) 1093 1094STEXI 1095 1096@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}][,fmode=@var{fmode}][,dmode=@var{dmode}] 1097@findex -virtfs 1098 1099The general form of a Virtual File system pass-through options are: 1100@table @option 1101@item @var{fsdriver} 1102This option specifies the fs driver backend to use. 1103Currently "local", "handle" and "proxy" file system drivers are supported. 1104@item id=@var{id} 1105Specifies identifier for this device 1106@item path=@var{path} 1107Specifies the export path for the file system device. Files under 1108this path will be available to the 9p client on the guest. 1109@item security_model=@var{security_model} 1110Specifies the security model to be used for this export path. 1111Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 1112In "passthrough" security model, files are stored using the same 1113credentials as they are created on the guest. This requires QEMU 1114to run as root. In "mapped-xattr" security model, some of the file 1115attributes like uid, gid, mode bits and link target are stored as 1116file attributes. For "mapped-file" these attributes are stored in the 1117hidden .virtfs_metadata directory. Directories exported by this security model cannot 1118interact with other unix tools. "none" security model is same as 1119passthrough except the sever won't report failures if it fails to 1120set file attributes like ownership. Security model is mandatory only 1121for local fsdriver. Other fsdrivers (like handle, proxy) don't take security 1122model as a parameter. 1123@item writeout=@var{writeout} 1124This is an optional argument. The only supported value is "immediate". 1125This means that host page cache will be used to read and write data but 1126write notification will be sent to the guest only when the data has been 1127reported as written by the storage subsystem. 1128@item readonly 1129Enables exporting 9p share as a readonly mount for guests. By default 1130read-write access is given. 1131@item socket=@var{socket} 1132Enables proxy filesystem driver to use passed socket file for 1133communicating with virtfs-proxy-helper. Usually a helper like libvirt 1134will create socketpair and pass one of the fds as sock_fd 1135@item sock_fd 1136Enables proxy filesystem driver to use passed 'sock_fd' as the socket 1137descriptor for interfacing with virtfs-proxy-helper 1138@item fmode=@var{fmode} 1139Specifies the default mode for newly created files on the host. Works only 1140with security models "mapped-xattr" and "mapped-file". 1141@item dmode=@var{dmode} 1142Specifies the default mode for newly created directories on the host. Works 1143only with security models "mapped-xattr" and "mapped-file". 1144@end table 1145ETEXI 1146 1147DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth, 1148 "-virtfs_synth Create synthetic file system image\n", 1149 QEMU_ARCH_ALL) 1150STEXI 1151@item -virtfs_synth 1152@findex -virtfs_synth 1153Create synthetic file system image 1154ETEXI 1155 1156STEXI 1157@end table 1158ETEXI 1159DEFHEADING() 1160 1161DEFHEADING(USB options) 1162STEXI 1163@table @option 1164ETEXI 1165 1166DEF("usb", 0, QEMU_OPTION_usb, 1167 "-usb enable the USB driver (if it is not used by default yet)\n", 1168 QEMU_ARCH_ALL) 1169STEXI 1170@item -usb 1171@findex -usb 1172Enable the USB driver (if it is not used by default yet). 1173ETEXI 1174 1175DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice, 1176 "-usbdevice name add the host or guest USB device 'name'\n", 1177 QEMU_ARCH_ALL) 1178STEXI 1179 1180@item -usbdevice @var{devname} 1181@findex -usbdevice 1182Add the USB device @var{devname}. Note that this option is deprecated, 1183please use @code{-device usb-...} instead. @xref{usb_devices}. 1184 1185@table @option 1186 1187@item mouse 1188Virtual Mouse. This will override the PS/2 mouse emulation when activated. 1189 1190@item tablet 1191Pointer device that uses absolute coordinates (like a touchscreen). This 1192means QEMU is able to report the mouse position without having to grab the 1193mouse. Also overrides the PS/2 mouse emulation when activated. 1194 1195@item disk:[format=@var{format}]:@var{file} 1196Mass storage device based on file. The optional @var{format} argument 1197will be used rather than detecting the format. Can be used to specify 1198@code{format=raw} to avoid interpreting an untrusted format header. 1199 1200@item host:@var{bus}.@var{addr} 1201Pass through the host device identified by @var{bus}.@var{addr} (Linux only). 1202 1203@item host:@var{vendor_id}:@var{product_id} 1204Pass through the host device identified by @var{vendor_id}:@var{product_id} 1205(Linux only). 1206 1207@item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev} 1208Serial converter to host character device @var{dev}, see @code{-serial} for the 1209available devices. 1210 1211@item braille 1212Braille device. This will use BrlAPI to display the braille output on a real 1213or fake device. 1214 1215@item net:@var{options} 1216Network adapter that supports CDC ethernet and RNDIS protocols. 1217 1218@end table 1219ETEXI 1220 1221STEXI 1222@end table 1223ETEXI 1224DEFHEADING() 1225 1226DEFHEADING(Display options) 1227STEXI 1228@table @option 1229ETEXI 1230 1231DEF("display", HAS_ARG, QEMU_OPTION_display, 1232 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n" 1233 " [,window_close=on|off][,gl=on|off]\n" 1234 "-display gtk[,grab_on_hover=on|off][,gl=on|off]|\n" 1235 "-display vnc=<display>[,<optargs>]\n" 1236 "-display curses\n" 1237 "-display none" 1238 " select display type\n" 1239 "The default display is equivalent to\n" 1240#if defined(CONFIG_GTK) 1241 "\t\"-display gtk\"\n" 1242#elif defined(CONFIG_SDL) 1243 "\t\"-display sdl\"\n" 1244#elif defined(CONFIG_COCOA) 1245 "\t\"-display cocoa\"\n" 1246#elif defined(CONFIG_VNC) 1247 "\t\"-vnc localhost:0,to=99,id=default\"\n" 1248#else 1249 "\t\"-display none\"\n" 1250#endif 1251 , QEMU_ARCH_ALL) 1252STEXI 1253@item -display @var{type} 1254@findex -display 1255Select type of display to use. This option is a replacement for the 1256old style -sdl/-curses/... options. Valid values for @var{type} are 1257@table @option 1258@item sdl 1259Display video output via SDL (usually in a separate graphics 1260window; see the SDL documentation for other possibilities). 1261@item curses 1262Display video output via curses. For graphics device models which 1263support a text mode, QEMU can display this output using a 1264curses/ncurses interface. Nothing is displayed when the graphics 1265device is in graphical mode or if the graphics device does not support 1266a text mode. Generally only the VGA device models support text mode. 1267@item none 1268Do not display video output. The guest will still see an emulated 1269graphics card, but its output will not be displayed to the QEMU 1270user. This option differs from the -nographic option in that it 1271only affects what is done with video output; -nographic also changes 1272the destination of the serial and parallel port data. 1273@item gtk 1274Display video output in a GTK window. This interface provides drop-down 1275menus and other UI elements to configure and control the VM during 1276runtime. 1277@item vnc 1278Start a VNC server on display <arg> 1279@end table 1280ETEXI 1281 1282DEF("nographic", 0, QEMU_OPTION_nographic, 1283 "-nographic disable graphical output and redirect serial I/Os to console\n", 1284 QEMU_ARCH_ALL) 1285STEXI 1286@item -nographic 1287@findex -nographic 1288Normally, if QEMU is compiled with graphical window support, it displays 1289output such as guest graphics, guest console, and the QEMU monitor in a 1290window. With this option, you can totally disable graphical output so 1291that QEMU is a simple command line application. The emulated serial port 1292is redirected on the console and muxed with the monitor (unless 1293redirected elsewhere explicitly). Therefore, you can still use QEMU to 1294debug a Linux kernel with a serial console. Use @key{C-a h} for help on 1295switching between the console and monitor. 1296ETEXI 1297 1298DEF("curses", 0, QEMU_OPTION_curses, 1299 "-curses shorthand for -display curses\n", 1300 QEMU_ARCH_ALL) 1301STEXI 1302@item -curses 1303@findex -curses 1304Normally, if QEMU is compiled with graphical window support, it displays 1305output such as guest graphics, guest console, and the QEMU monitor in a 1306window. With this option, QEMU can display the VGA output when in text 1307mode using a curses/ncurses interface. Nothing is displayed in graphical 1308mode. 1309ETEXI 1310 1311DEF("no-frame", 0, QEMU_OPTION_no_frame, 1312 "-no-frame open SDL window without a frame and window decorations\n", 1313 QEMU_ARCH_ALL) 1314STEXI 1315@item -no-frame 1316@findex -no-frame 1317Do not use decorations for SDL windows and start them using the whole 1318available screen space. This makes the using QEMU in a dedicated desktop 1319workspace more convenient. 1320ETEXI 1321 1322DEF("alt-grab", 0, QEMU_OPTION_alt_grab, 1323 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n", 1324 QEMU_ARCH_ALL) 1325STEXI 1326@item -alt-grab 1327@findex -alt-grab 1328Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also 1329affects the special keys (for fullscreen, monitor-mode switching, etc). 1330ETEXI 1331 1332DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab, 1333 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n", 1334 QEMU_ARCH_ALL) 1335STEXI 1336@item -ctrl-grab 1337@findex -ctrl-grab 1338Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also 1339affects the special keys (for fullscreen, monitor-mode switching, etc). 1340ETEXI 1341 1342DEF("no-quit", 0, QEMU_OPTION_no_quit, 1343 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL) 1344STEXI 1345@item -no-quit 1346@findex -no-quit 1347Disable SDL window close capability. 1348ETEXI 1349 1350DEF("sdl", 0, QEMU_OPTION_sdl, 1351 "-sdl shorthand for -display sdl\n", QEMU_ARCH_ALL) 1352STEXI 1353@item -sdl 1354@findex -sdl 1355Enable SDL. 1356ETEXI 1357 1358DEF("spice", HAS_ARG, QEMU_OPTION_spice, 1359 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n" 1360 " [,x509-key-file=<file>][,x509-key-password=<file>]\n" 1361 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n" 1362 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n" 1363 " [,tls-ciphers=<list>]\n" 1364 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n" 1365 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n" 1366 " [,sasl][,password=<secret>][,disable-ticketing]\n" 1367 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n" 1368 " [,jpeg-wan-compression=[auto|never|always]]\n" 1369 " [,zlib-glz-wan-compression=[auto|never|always]]\n" 1370 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n" 1371 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n" 1372 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n" 1373 " [,gl=[on|off]][,rendernode=<file>]\n" 1374 " enable spice\n" 1375 " at least one of {port, tls-port} is mandatory\n", 1376 QEMU_ARCH_ALL) 1377STEXI 1378@item -spice @var{option}[,@var{option}[,...]] 1379@findex -spice 1380Enable the spice remote desktop protocol. Valid options are 1381 1382@table @option 1383 1384@item port=<nr> 1385Set the TCP port spice is listening on for plaintext channels. 1386 1387@item addr=<addr> 1388Set the IP address spice is listening on. Default is any address. 1389 1390@item ipv4 1391@itemx ipv6 1392@itemx unix 1393Force using the specified IP version. 1394 1395@item password=<secret> 1396Set the password you need to authenticate. 1397 1398@item sasl 1399Require that the client use SASL to authenticate with the spice. 1400The exact choice of authentication method used is controlled from the 1401system / user's SASL configuration file for the 'qemu' service. This 1402is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1403unprivileged user, an environment variable SASL_CONF_PATH can be used 1404to make it search alternate locations for the service config. 1405While some SASL auth methods can also provide data encryption (eg GSSAPI), 1406it is recommended that SASL always be combined with the 'tls' and 1407'x509' settings to enable use of SSL and server certificates. This 1408ensures a data encryption preventing compromise of authentication 1409credentials. 1410 1411@item disable-ticketing 1412Allow client connects without authentication. 1413 1414@item disable-copy-paste 1415Disable copy paste between the client and the guest. 1416 1417@item disable-agent-file-xfer 1418Disable spice-vdagent based file-xfer between the client and the guest. 1419 1420@item tls-port=<nr> 1421Set the TCP port spice is listening on for encrypted channels. 1422 1423@item x509-dir=<dir> 1424Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir 1425 1426@item x509-key-file=<file> 1427@itemx x509-key-password=<file> 1428@itemx x509-cert-file=<file> 1429@itemx x509-cacert-file=<file> 1430@itemx x509-dh-key-file=<file> 1431The x509 file names can also be configured individually. 1432 1433@item tls-ciphers=<list> 1434Specify which ciphers to use. 1435 1436@item tls-channel=[main|display|cursor|inputs|record|playback] 1437@itemx plaintext-channel=[main|display|cursor|inputs|record|playback] 1438Force specific channel to be used with or without TLS encryption. The 1439options can be specified multiple times to configure multiple 1440channels. The special name "default" can be used to set the default 1441mode. For channels which are not explicitly forced into one mode the 1442spice client is allowed to pick tls/plaintext as he pleases. 1443 1444@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off] 1445Configure image compression (lossless). 1446Default is auto_glz. 1447 1448@item jpeg-wan-compression=[auto|never|always] 1449@itemx zlib-glz-wan-compression=[auto|never|always] 1450Configure wan image compression (lossy for slow links). 1451Default is auto. 1452 1453@item streaming-video=[off|all|filter] 1454Configure video stream detection. Default is off. 1455 1456@item agent-mouse=[on|off] 1457Enable/disable passing mouse events via vdagent. Default is on. 1458 1459@item playback-compression=[on|off] 1460Enable/disable audio stream compression (using celt 0.5.1). Default is on. 1461 1462@item seamless-migration=[on|off] 1463Enable/disable spice seamless migration. Default is off. 1464 1465@item gl=[on|off] 1466Enable/disable OpenGL context. Default is off. 1467 1468@item rendernode=<file> 1469DRM render node for OpenGL rendering. If not specified, it will pick 1470the first available. (Since 2.9) 1471 1472@end table 1473ETEXI 1474 1475DEF("portrait", 0, QEMU_OPTION_portrait, 1476 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n", 1477 QEMU_ARCH_ALL) 1478STEXI 1479@item -portrait 1480@findex -portrait 1481Rotate graphical output 90 deg left (only PXA LCD). 1482ETEXI 1483 1484DEF("rotate", HAS_ARG, QEMU_OPTION_rotate, 1485 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n", 1486 QEMU_ARCH_ALL) 1487STEXI 1488@item -rotate @var{deg} 1489@findex -rotate 1490Rotate graphical output some deg left (only PXA LCD). 1491ETEXI 1492 1493DEF("vga", HAS_ARG, QEMU_OPTION_vga, 1494 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n" 1495 " select video card type\n", QEMU_ARCH_ALL) 1496STEXI 1497@item -vga @var{type} 1498@findex -vga 1499Select type of VGA card to emulate. Valid values for @var{type} are 1500@table @option 1501@item cirrus 1502Cirrus Logic GD5446 Video card. All Windows versions starting from 1503Windows 95 should recognize and use this graphic card. For optimal 1504performances, use 16 bit color depth in the guest and the host OS. 1505(This card was the default before QEMU 2.2) 1506@item std 1507Standard VGA card with Bochs VBE extensions. If your guest OS 1508supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want 1509to use high resolution modes (>= 1280x1024x16) then you should use 1510this option. (This card is the default since QEMU 2.2) 1511@item vmware 1512VMWare SVGA-II compatible adapter. Use it if you have sufficiently 1513recent XFree86/XOrg server or Windows guest with a driver for this 1514card. 1515@item qxl 1516QXL paravirtual graphic card. It is VGA compatible (including VESA 15172.0 VBE support). Works best with qxl guest drivers installed though. 1518Recommended choice when using the spice protocol. 1519@item tcx 1520(sun4m only) Sun TCX framebuffer. This is the default framebuffer for 1521sun4m machines and offers both 8-bit and 24-bit colour depths at a 1522fixed resolution of 1024x768. 1523@item cg3 1524(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer 1525for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP) 1526resolutions aimed at people wishing to run older Solaris versions. 1527@item virtio 1528Virtio VGA card. 1529@item none 1530Disable VGA card. 1531@end table 1532ETEXI 1533 1534DEF("full-screen", 0, QEMU_OPTION_full_screen, 1535 "-full-screen start in full screen\n", QEMU_ARCH_ALL) 1536STEXI 1537@item -full-screen 1538@findex -full-screen 1539Start in full screen. 1540ETEXI 1541 1542DEF("g", 1, QEMU_OPTION_g , 1543 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n", 1544 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 1545STEXI 1546@item -g @var{width}x@var{height}[x@var{depth}] 1547@findex -g 1548Set the initial graphical resolution and depth (PPC, SPARC only). 1549ETEXI 1550 1551DEF("vnc", HAS_ARG, QEMU_OPTION_vnc , 1552 "-vnc <display> shorthand for -display vnc=<display>\n", QEMU_ARCH_ALL) 1553STEXI 1554@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]] 1555@findex -vnc 1556Normally, if QEMU is compiled with graphical window support, it displays 1557output such as guest graphics, guest console, and the QEMU monitor in a 1558window. With this option, you can have QEMU listen on VNC display 1559@var{display} and redirect the VGA display over the VNC session. It is 1560very useful to enable the usb tablet device when using this option 1561(option @option{-device usb-tablet}). When using the VNC display, you 1562must use the @option{-k} parameter to set the keyboard layout if you are 1563not using en-us. Valid syntax for the @var{display} is 1564 1565@table @option 1566 1567@item to=@var{L} 1568 1569With this option, QEMU will try next available VNC @var{display}s, until the 1570number @var{L}, if the origianlly defined "-vnc @var{display}" is not 1571available, e.g. port 5900+@var{display} is already used by another 1572application. By default, to=0. 1573 1574@item @var{host}:@var{d} 1575 1576TCP connections will only be allowed from @var{host} on display @var{d}. 1577By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can 1578be omitted in which case the server will accept connections from any host. 1579 1580@item unix:@var{path} 1581 1582Connections will be allowed over UNIX domain sockets where @var{path} is the 1583location of a unix socket to listen for connections on. 1584 1585@item none 1586 1587VNC is initialized but not started. The monitor @code{change} command 1588can be used to later start the VNC server. 1589 1590@end table 1591 1592Following the @var{display} value there may be one or more @var{option} flags 1593separated by commas. Valid options are 1594 1595@table @option 1596 1597@item reverse 1598 1599Connect to a listening VNC client via a ``reverse'' connection. The 1600client is specified by the @var{display}. For reverse network 1601connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument 1602is a TCP port number, not a display number. 1603 1604@item websocket 1605 1606Opens an additional TCP listening port dedicated to VNC Websocket connections. 1607If a bare @var{websocket} option is given, the Websocket port is 16085700+@var{display}. An alternative port can be specified with the 1609syntax @code{websocket}=@var{port}. 1610 1611If @var{host} is specified connections will only be allowed from this host. 1612It is possible to control the websocket listen address independently, using 1613the syntax @code{websocket}=@var{host}:@var{port}. 1614 1615If no TLS credentials are provided, the websocket connection runs in 1616unencrypted mode. If TLS credentials are provided, the websocket connection 1617requires encrypted client connections. 1618 1619@item password 1620 1621Require that password based authentication is used for client connections. 1622 1623The password must be set separately using the @code{set_password} command in 1624the @ref{pcsys_monitor}. The syntax to change your password is: 1625@code{set_password <protocol> <password>} where <protocol> could be either 1626"vnc" or "spice". 1627 1628If you would like to change <protocol> password expiration, you should use 1629@code{expire_password <protocol> <expiration-time>} where expiration time could 1630be one of the following options: now, never, +seconds or UNIX time of 1631expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800 1632to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this 1633date and time). 1634 1635You can also use keywords "now" or "never" for the expiration time to 1636allow <protocol> password to expire immediately or never expire. 1637 1638@item tls-creds=@var{ID} 1639 1640Provides the ID of a set of TLS credentials to use to secure the 1641VNC server. They will apply to both the normal VNC server socket 1642and the websocket socket (if enabled). Setting TLS credentials 1643will cause the VNC server socket to enable the VeNCrypt auth 1644mechanism. The credentials should have been previously created 1645using the @option{-object tls-creds} argument. 1646 1647The @option{tls-creds} parameter obsoletes the @option{tls}, 1648@option{x509}, and @option{x509verify} options, and as such 1649it is not permitted to set both new and old type options at 1650the same time. 1651 1652@item tls 1653 1654Require that client use TLS when communicating with the VNC server. This 1655uses anonymous TLS credentials so is susceptible to a man-in-the-middle 1656attack. It is recommended that this option be combined with either the 1657@option{x509} or @option{x509verify} options. 1658 1659This option is now deprecated in favor of using the @option{tls-creds} 1660argument. 1661 1662@item x509=@var{/path/to/certificate/dir} 1663 1664Valid if @option{tls} is specified. Require that x509 credentials are used 1665for negotiating the TLS session. The server will send its x509 certificate 1666to the client. It is recommended that a password be set on the VNC server 1667to provide authentication of the client when this is used. The path following 1668this option specifies where the x509 certificates are to be loaded from. 1669See the @ref{vnc_security} section for details on generating certificates. 1670 1671This option is now deprecated in favour of using the @option{tls-creds} 1672argument. 1673 1674@item x509verify=@var{/path/to/certificate/dir} 1675 1676Valid if @option{tls} is specified. Require that x509 credentials are used 1677for negotiating the TLS session. The server will send its x509 certificate 1678to the client, and request that the client send its own x509 certificate. 1679The server will validate the client's certificate against the CA certificate, 1680and reject clients when validation fails. If the certificate authority is 1681trusted, this is a sufficient authentication mechanism. You may still wish 1682to set a password on the VNC server as a second authentication layer. The 1683path following this option specifies where the x509 certificates are to 1684be loaded from. See the @ref{vnc_security} section for details on generating 1685certificates. 1686 1687This option is now deprecated in favour of using the @option{tls-creds} 1688argument. 1689 1690@item sasl 1691 1692Require that the client use SASL to authenticate with the VNC server. 1693The exact choice of authentication method used is controlled from the 1694system / user's SASL configuration file for the 'qemu' service. This 1695is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1696unprivileged user, an environment variable SASL_CONF_PATH can be used 1697to make it search alternate locations for the service config. 1698While some SASL auth methods can also provide data encryption (eg GSSAPI), 1699it is recommended that SASL always be combined with the 'tls' and 1700'x509' settings to enable use of SSL and server certificates. This 1701ensures a data encryption preventing compromise of authentication 1702credentials. See the @ref{vnc_security} section for details on using 1703SASL authentication. 1704 1705@item acl 1706 1707Turn on access control lists for checking of the x509 client certificate 1708and SASL party. For x509 certs, the ACL check is made against the 1709certificate's distinguished name. This is something that looks like 1710@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is 1711made against the username, which depending on the SASL plugin, may 1712include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}. 1713When the @option{acl} flag is set, the initial access list will be 1714empty, with a @code{deny} policy. Thus no one will be allowed to 1715use the VNC server until the ACLs have been loaded. This can be 1716achieved using the @code{acl} monitor command. 1717 1718@item lossy 1719 1720Enable lossy compression methods (gradient, JPEG, ...). If this 1721option is set, VNC client may receive lossy framebuffer updates 1722depending on its encoding settings. Enabling this option can save 1723a lot of bandwidth at the expense of quality. 1724 1725@item non-adaptive 1726 1727Disable adaptive encodings. Adaptive encodings are enabled by default. 1728An adaptive encoding will try to detect frequently updated screen regions, 1729and send updates in these regions using a lossy encoding (like JPEG). 1730This can be really helpful to save bandwidth when playing videos. Disabling 1731adaptive encodings restores the original static behavior of encodings 1732like Tight. 1733 1734@item share=[allow-exclusive|force-shared|ignore] 1735 1736Set display sharing policy. 'allow-exclusive' allows clients to ask 1737for exclusive access. As suggested by the rfb spec this is 1738implemented by dropping other connections. Connecting multiple 1739clients in parallel requires all clients asking for a shared session 1740(vncviewer: -shared switch). This is the default. 'force-shared' 1741disables exclusive client access. Useful for shared desktop sessions, 1742where you don't want someone forgetting specify -shared disconnect 1743everybody else. 'ignore' completely ignores the shared flag and 1744allows everybody connect unconditionally. Doesn't conform to the rfb 1745spec but is traditional QEMU behavior. 1746 1747@item key-delay-ms 1748 1749Set keyboard delay, for key down and key up events, in milliseconds. 1750Default is 1. Keyboards are low-bandwidth devices, so this slowdown 1751can help the device and guest to keep up and not lose events in case 1752events are arriving in bulk. Possible causes for the latter are flaky 1753network connections, or scripts for automated testing. 1754 1755@end table 1756ETEXI 1757 1758STEXI 1759@end table 1760ETEXI 1761ARCHHEADING(, QEMU_ARCH_I386) 1762 1763ARCHHEADING(i386 target only, QEMU_ARCH_I386) 1764STEXI 1765@table @option 1766ETEXI 1767 1768DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack, 1769 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n", 1770 QEMU_ARCH_I386) 1771STEXI 1772@item -win2k-hack 1773@findex -win2k-hack 1774Use it when installing Windows 2000 to avoid a disk full bug. After 1775Windows 2000 is installed, you no longer need this option (this option 1776slows down the IDE transfers). 1777ETEXI 1778 1779HXCOMM Deprecated by -rtc 1780DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386) 1781 1782DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk, 1783 "-no-fd-bootchk disable boot signature checking for floppy disks\n", 1784 QEMU_ARCH_I386) 1785STEXI 1786@item -no-fd-bootchk 1787@findex -no-fd-bootchk 1788Disable boot signature checking for floppy disks in BIOS. May 1789be needed to boot from old floppy disks. 1790ETEXI 1791 1792DEF("no-acpi", 0, QEMU_OPTION_no_acpi, 1793 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1794STEXI 1795@item -no-acpi 1796@findex -no-acpi 1797Disable ACPI (Advanced Configuration and Power Interface) support. Use 1798it if your guest OS complains about ACPI problems (PC target machine 1799only). 1800ETEXI 1801 1802DEF("no-hpet", 0, QEMU_OPTION_no_hpet, 1803 "-no-hpet disable HPET\n", QEMU_ARCH_I386) 1804STEXI 1805@item -no-hpet 1806@findex -no-hpet 1807Disable HPET support. 1808ETEXI 1809 1810DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable, 1811 "-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" 1812 " ACPI table description\n", QEMU_ARCH_I386) 1813STEXI 1814@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}]...] 1815@findex -acpitable 1816Add ACPI table with specified header fields and context from specified files. 1817For file=, take whole ACPI table from the specified files, including all 1818ACPI headers (possible overridden by other options). 1819For data=, only data 1820portion of the table is used, all header information is specified in the 1821command line. 1822If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id 1823fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order 1824to ensure the field matches required by the Microsoft SLIC spec and the ACPI 1825spec. 1826ETEXI 1827 1828DEF("smbios", HAS_ARG, QEMU_OPTION_smbios, 1829 "-smbios file=binary\n" 1830 " load SMBIOS entry from binary file\n" 1831 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n" 1832 " [,uefi=on|off]\n" 1833 " specify SMBIOS type 0 fields\n" 1834 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1835 " [,uuid=uuid][,sku=str][,family=str]\n" 1836 " specify SMBIOS type 1 fields\n" 1837 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1838 " [,asset=str][,location=str]\n" 1839 " specify SMBIOS type 2 fields\n" 1840 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n" 1841 " [,sku=str]\n" 1842 " specify SMBIOS type 3 fields\n" 1843 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n" 1844 " [,asset=str][,part=str]\n" 1845 " specify SMBIOS type 4 fields\n" 1846 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n" 1847 " [,asset=str][,part=str][,speed=%d]\n" 1848 " specify SMBIOS type 17 fields\n", 1849 QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1850STEXI 1851@item -smbios file=@var{binary} 1852@findex -smbios 1853Load SMBIOS entry from binary file. 1854 1855@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off] 1856Specify SMBIOS type 0 fields 1857 1858@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}] 1859Specify SMBIOS type 1 fields 1860 1861@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}] 1862Specify SMBIOS type 2 fields 1863 1864@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}] 1865Specify SMBIOS type 3 fields 1866 1867@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}] 1868Specify SMBIOS type 4 fields 1869 1870@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}] 1871Specify SMBIOS type 17 fields 1872ETEXI 1873 1874STEXI 1875@end table 1876ETEXI 1877DEFHEADING() 1878 1879DEFHEADING(Network options) 1880STEXI 1881@table @option 1882ETEXI 1883 1884HXCOMM Legacy slirp options (now moved to -net user): 1885#ifdef CONFIG_SLIRP 1886DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL) 1887DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL) 1888DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL) 1889#ifndef _WIN32 1890DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL) 1891#endif 1892#endif 1893 1894DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, 1895#ifdef CONFIG_SLIRP 1896 "-netdev user,id=str[,ipv4[=on|off]][,net=addr[/mask]][,host=addr]\n" 1897 " [,ipv6[=on|off]][,ipv6-net=addr[/int]][,ipv6-host=addr]\n" 1898 " [,restrict=on|off][,hostname=host][,dhcpstart=addr]\n" 1899 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,tftp=dir]\n" 1900 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]" 1901#ifndef _WIN32 1902 "[,smb=dir[,smbserver=addr]]\n" 1903#endif 1904 " configure a user mode network backend with ID 'str',\n" 1905 " its DHCP server and optional services\n" 1906#endif 1907#ifdef _WIN32 1908 "-netdev tap,id=str,ifname=name\n" 1909 " configure a host TAP network backend with ID 'str'\n" 1910#else 1911 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n" 1912 " [,br=bridge][,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n" 1913 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n" 1914 " [,poll-us=n]\n" 1915 " configure a host TAP network backend with ID 'str'\n" 1916 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 1917 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n" 1918 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n" 1919 " to deconfigure it\n" 1920 " use '[down]script=no' to disable script execution\n" 1921 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n" 1922 " configure it\n" 1923 " use 'fd=h' to connect to an already opened TAP interface\n" 1924 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n" 1925 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n" 1926 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n" 1927 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n" 1928 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" 1929 " use vhost=on to enable experimental in kernel accelerator\n" 1930 " (only has effect for virtio guests which use MSIX)\n" 1931 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n" 1932 " use 'vhostfd=h' to connect to an already opened vhost net device\n" 1933 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n" 1934 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n" 1935 " use 'poll-us=n' to speciy the maximum number of microseconds that could be\n" 1936 " spent on busy polling for vhost net\n" 1937 "-netdev bridge,id=str[,br=bridge][,helper=helper]\n" 1938 " configure a host TAP network backend with ID 'str' that is\n" 1939 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 1940 " using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n" 1941#endif 1942#ifdef __linux__ 1943 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n" 1944 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n" 1945 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n" 1946 " [,rxcookie=rxcookie][,offset=offset]\n" 1947 " configure a network backend with ID 'str' connected to\n" 1948 " an Ethernet over L2TPv3 pseudowire.\n" 1949 " Linux kernel 3.3+ as well as most routers can talk\n" 1950 " L2TPv3. This transport allows connecting a VM to a VM,\n" 1951 " VM to a router and even VM to Host. It is a nearly-universal\n" 1952 " standard (RFC3391). Note - this implementation uses static\n" 1953 " pre-configured tunnels (same as the Linux kernel).\n" 1954 " use 'src=' to specify source address\n" 1955 " use 'dst=' to specify destination address\n" 1956 " use 'udp=on' to specify udp encapsulation\n" 1957 " use 'srcport=' to specify source udp port\n" 1958 " use 'dstport=' to specify destination udp port\n" 1959 " use 'ipv6=on' to force v6\n" 1960 " L2TPv3 uses cookies to prevent misconfiguration as\n" 1961 " well as a weak security measure\n" 1962 " use 'rxcookie=0x012345678' to specify a rxcookie\n" 1963 " use 'txcookie=0x012345678' to specify a txcookie\n" 1964 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n" 1965 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n" 1966 " use 'pincounter=on' to work around broken counter handling in peer\n" 1967 " use 'offset=X' to add an extra offset between header and data\n" 1968#endif 1969 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n" 1970 " configure a network backend to connect to another network\n" 1971 " using a socket connection\n" 1972 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n" 1973 " configure a network backend to connect to a multicast maddr and port\n" 1974 " use 'localaddr=addr' to specify the host address to send packets from\n" 1975 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n" 1976 " configure a network backend to connect to another network\n" 1977 " using an UDP tunnel\n" 1978#ifdef CONFIG_VDE 1979 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n" 1980 " configure a network backend to connect to port 'n' of a vde switch\n" 1981 " running on host and listening for incoming connections on 'socketpath'.\n" 1982 " Use group 'groupname' and mode 'octalmode' to change default\n" 1983 " ownership and permissions for communication port.\n" 1984#endif 1985#ifdef CONFIG_NETMAP 1986 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n" 1987 " attach to the existing netmap-enabled network interface 'name', or to a\n" 1988 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n" 1989 " netmap device, defaults to '/dev/netmap')\n" 1990#endif 1991 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n" 1992 " configure a vhost-user network, backed by a chardev 'dev'\n" 1993 "-netdev hubport,id=str,hubid=n\n" 1994 " configure a hub port on QEMU VLAN 'n'\n", QEMU_ARCH_ALL) 1995DEF("net", HAS_ARG, QEMU_OPTION_net, 1996 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n" 1997 " old way to create a new NIC and connect it to VLAN 'n'\n" 1998 " (use the '-device devtype,netdev=str' option if possible instead)\n" 1999 "-net dump[,vlan=n][,file=f][,len=n]\n" 2000 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n" 2001 "-net none use it alone to have zero network devices. If no -net option\n" 2002 " is provided, the default is '-net nic -net user'\n" 2003 "-net [" 2004#ifdef CONFIG_SLIRP 2005 "user|" 2006#endif 2007 "tap|" 2008 "bridge|" 2009#ifdef CONFIG_VDE 2010 "vde|" 2011#endif 2012#ifdef CONFIG_NETMAP 2013 "netmap|" 2014#endif 2015 "socket][,vlan=n][,option][,option][,...]\n" 2016 " old way to initialize a host network interface\n" 2017 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL) 2018STEXI 2019@item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}] 2020@findex -net 2021Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n} 2022= 0 is the default). The NIC is an e1000 by default on the PC 2023target. Optionally, the MAC address can be changed to @var{mac}, the 2024device address set to @var{addr} (PCI cards only), 2025and a @var{name} can be assigned for use in monitor commands. 2026Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors 2027that the card should have; this option currently only affects virtio cards; set 2028@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single 2029NIC is created. QEMU can emulate several different models of network card. 2030Valid values for @var{type} are 2031@code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er}, 2032@code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139}, 2033@code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}. 2034Not all devices are supported on all targets. Use @code{-net nic,model=help} 2035for a list of available devices for your target. 2036 2037@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...] 2038@findex -netdev 2039@item -net user[,@var{option}][,@var{option}][,...] 2040Use the user mode network stack which requires no administrator 2041privilege to run. Valid options are: 2042 2043@table @option 2044@item vlan=@var{n} 2045Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default). 2046 2047@item id=@var{id} 2048@itemx name=@var{name} 2049Assign symbolic name for use in monitor commands. 2050 2051@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must 2052be enabled. If neither is specified both protocols are enabled. 2053 2054@item net=@var{addr}[/@var{mask}] 2055Set IP network address the guest will see. Optionally specify the netmask, 2056either in the form a.b.c.d or as number of valid top-most bits. Default is 205710.0.2.0/24. 2058 2059@item host=@var{addr} 2060Specify the guest-visible address of the host. Default is the 2nd IP in the 2061guest network, i.e. x.x.x.2. 2062 2063@item ipv6-net=@var{addr}[/@var{int}] 2064Set IPv6 network address the guest will see (default is fec0::/64). The 2065network prefix is given in the usual hexadecimal IPv6 address 2066notation. The prefix size is optional, and is given as the number of 2067valid top-most bits (default is 64). 2068 2069@item ipv6-host=@var{addr} 2070Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in 2071the guest network, i.e. xxxx::2. 2072 2073@item restrict=on|off 2074If this option is enabled, the guest will be isolated, i.e. it will not be 2075able to contact the host and no guest IP packets will be routed over the host 2076to the outside. This option does not affect any explicitly set forwarding rules. 2077 2078@item hostname=@var{name} 2079Specifies the client hostname reported by the built-in DHCP server. 2080 2081@item dhcpstart=@var{addr} 2082Specify the first of the 16 IPs the built-in DHCP server can assign. Default 2083is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31. 2084 2085@item dns=@var{addr} 2086Specify the guest-visible address of the virtual nameserver. The address must 2087be different from the host address. Default is the 3rd IP in the guest network, 2088i.e. x.x.x.3. 2089 2090@item ipv6-dns=@var{addr} 2091Specify the guest-visible address of the IPv6 virtual nameserver. The address 2092must be different from the host address. Default is the 3rd IP in the guest 2093network, i.e. xxxx::3. 2094 2095@item dnssearch=@var{domain} 2096Provides an entry for the domain-search list sent by the built-in 2097DHCP server. More than one domain suffix can be transmitted by specifying 2098this option multiple times. If supported, this will cause the guest to 2099automatically try to append the given domain suffix(es) in case a domain name 2100can not be resolved. 2101 2102Example: 2103@example 2104qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...] 2105@end example 2106 2107@item tftp=@var{dir} 2108When using the user mode network stack, activate a built-in TFTP 2109server. The files in @var{dir} will be exposed as the root of a TFTP server. 2110The TFTP client on the guest must be configured in binary mode (use the command 2111@code{bin} of the Unix TFTP client). 2112 2113@item bootfile=@var{file} 2114When using the user mode network stack, broadcast @var{file} as the BOOTP 2115filename. In conjunction with @option{tftp}, this can be used to network boot 2116a guest from a local directory. 2117 2118Example (using pxelinux): 2119@example 2120qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0 2121@end example 2122 2123@item smb=@var{dir}[,smbserver=@var{addr}] 2124When using the user mode network stack, activate a built-in SMB 2125server so that Windows OSes can access to the host files in @file{@var{dir}} 2126transparently. The IP address of the SMB server can be set to @var{addr}. By 2127default the 4th IP in the guest network is used, i.e. x.x.x.4. 2128 2129In the guest Windows OS, the line: 2130@example 213110.0.2.4 smbserver 2132@end example 2133must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me) 2134or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000). 2135 2136Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}. 2137 2138Note that a SAMBA server must be installed on the host OS. 2139QEMU was tested successfully with smbd versions from Red Hat 9, 2140Fedora Core 3 and OpenSUSE 11.x. 2141 2142@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport} 2143Redirect incoming TCP or UDP connections to the host port @var{hostport} to 2144the guest IP address @var{guestaddr} on guest port @var{guestport}. If 2145@var{guestaddr} is not specified, its value is x.x.x.15 (default first address 2146given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can 2147be bound to a specific host interface. If no connection type is set, TCP is 2148used. This option can be given multiple times. 2149 2150For example, to redirect host X11 connection from screen 1 to guest 2151screen 0, use the following: 2152 2153@example 2154# on the host 2155qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...] 2156# this host xterm should open in the guest X11 server 2157xterm -display :1 2158@end example 2159 2160To redirect telnet connections from host port 5555 to telnet port on 2161the guest, use the following: 2162 2163@example 2164# on the host 2165qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...] 2166telnet localhost 5555 2167@end example 2168 2169Then when you use on the host @code{telnet localhost 5555}, you 2170connect to the guest telnet server. 2171 2172@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev} 2173@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command} 2174Forward guest TCP connections to the IP address @var{server} on port @var{port} 2175to the character device @var{dev} or to a program executed by @var{cmd:command} 2176which gets spawned for each connection. This option can be given multiple times. 2177 2178You can either use a chardev directly and have that one used throughout QEMU's 2179lifetime, like in the following example: 2180 2181@example 2182# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever 2183# the guest accesses it 2184qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...] 2185@end example 2186 2187Or you can execute a command on every TCP connection established by the guest, 2188so that QEMU behaves similar to an inetd process for that virtual server: 2189 2190@example 2191# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 2192# and connect the TCP stream to its stdin/stdout 2193qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321' 2194@end example 2195 2196@end table 2197 2198Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still 2199processed and applied to -net user. Mixing them with the new configuration 2200syntax gives undefined results. Their use for new applications is discouraged 2201as they will be removed from future versions. 2202 2203@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}] 2204@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}] 2205Connect the host TAP network interface @var{name} to VLAN @var{n}. 2206 2207Use the network script @var{file} to configure it and the network script 2208@var{dfile} to deconfigure it. If @var{name} is not provided, the OS 2209automatically provides one. The default network configure script is 2210@file{/etc/qemu-ifup} and the default network deconfigure script is 2211@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no} 2212to disable script execution. 2213 2214If running QEMU as an unprivileged user, use the network helper 2215@var{helper} to configure the TAP interface and attach it to the bridge. 2216The default network helper executable is @file{/path/to/qemu-bridge-helper} 2217and the default bridge device is @file{br0}. 2218 2219@option{fd}=@var{h} can be used to specify the handle of an already 2220opened host TAP interface. 2221 2222Examples: 2223 2224@example 2225#launch a QEMU instance with the default network script 2226qemu-system-i386 linux.img -net nic -net tap 2227@end example 2228 2229@example 2230#launch a QEMU instance with two NICs, each one connected 2231#to a TAP device 2232qemu-system-i386 linux.img \ 2233 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \ 2234 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1 2235@end example 2236 2237@example 2238#launch a QEMU instance with the default network helper to 2239#connect a TAP device to bridge br0 2240qemu-system-i386 linux.img \ 2241 -net nic -net tap,"helper=/path/to/qemu-bridge-helper" 2242@end example 2243 2244@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}] 2245@itemx -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}] 2246Connect a host TAP network interface to a host bridge device. 2247 2248Use the network helper @var{helper} to configure the TAP interface and 2249attach it to the bridge. The default network helper executable is 2250@file{/path/to/qemu-bridge-helper} and the default bridge 2251device is @file{br0}. 2252 2253Examples: 2254 2255@example 2256#launch a QEMU instance with the default network helper to 2257#connect a TAP device to bridge br0 2258qemu-system-i386 linux.img -net bridge -net nic,model=virtio 2259@end example 2260 2261@example 2262#launch a QEMU instance with the default network helper to 2263#connect a TAP device to bridge qemubr0 2264qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio 2265@end example 2266 2267@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 2268@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 2269 2270Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual 2271machine using a TCP socket connection. If @option{listen} is 2272specified, QEMU waits for incoming connections on @var{port} 2273(@var{host} is optional). @option{connect} is used to connect to 2274another QEMU instance using the @option{listen} option. @option{fd}=@var{h} 2275specifies an already opened TCP socket. 2276 2277Example: 2278@example 2279# launch a first QEMU instance 2280qemu-system-i386 linux.img \ 2281 -net nic,macaddr=52:54:00:12:34:56 \ 2282 -net socket,listen=:1234 2283# connect the VLAN 0 of this instance to the VLAN 0 2284# of the first instance 2285qemu-system-i386 linux.img \ 2286 -net nic,macaddr=52:54:00:12:34:57 \ 2287 -net socket,connect=127.0.0.1:1234 2288@end example 2289 2290@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 2291@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 2292 2293Create a VLAN @var{n} shared with another QEMU virtual 2294machines using a UDP multicast socket, effectively making a bus for 2295every QEMU with same multicast address @var{maddr} and @var{port}. 2296NOTES: 2297@enumerate 2298@item 2299Several QEMU can be running on different hosts and share same bus (assuming 2300correct multicast setup for these hosts). 2301@item 2302mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see 2303@url{http://user-mode-linux.sf.net}. 2304@item 2305Use @option{fd=h} to specify an already opened UDP multicast socket. 2306@end enumerate 2307 2308Example: 2309@example 2310# launch one QEMU instance 2311qemu-system-i386 linux.img \ 2312 -net nic,macaddr=52:54:00:12:34:56 \ 2313 -net socket,mcast=230.0.0.1:1234 2314# launch another QEMU instance on same "bus" 2315qemu-system-i386 linux.img \ 2316 -net nic,macaddr=52:54:00:12:34:57 \ 2317 -net socket,mcast=230.0.0.1:1234 2318# launch yet another QEMU instance on same "bus" 2319qemu-system-i386 linux.img \ 2320 -net nic,macaddr=52:54:00:12:34:58 \ 2321 -net socket,mcast=230.0.0.1:1234 2322@end example 2323 2324Example (User Mode Linux compat.): 2325@example 2326# launch QEMU instance (note mcast address selected 2327# is UML's default) 2328qemu-system-i386 linux.img \ 2329 -net nic,macaddr=52:54:00:12:34:56 \ 2330 -net socket,mcast=239.192.168.1:1102 2331# launch UML 2332/path/to/linux ubd0=/path/to/root_fs eth0=mcast 2333@end example 2334 2335Example (send packets from host's 1.2.3.4): 2336@example 2337qemu-system-i386 linux.img \ 2338 -net nic,macaddr=52:54:00:12:34:56 \ 2339 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4 2340@end example 2341 2342@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}] 2343@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}] 2344Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular 2345protocol to transport Ethernet (and other Layer 2) data frames between 2346two systems. It is present in routers, firewalls and the Linux kernel 2347(from version 3.3 onwards). 2348 2349This transport allows a VM to communicate to another VM, router or firewall directly. 2350 2351@item src=@var{srcaddr} 2352 source address (mandatory) 2353@item dst=@var{dstaddr} 2354 destination address (mandatory) 2355@item udp 2356 select udp encapsulation (default is ip). 2357@item srcport=@var{srcport} 2358 source udp port. 2359@item dstport=@var{dstport} 2360 destination udp port. 2361@item ipv6 2362 force v6, otherwise defaults to v4. 2363@item rxcookie=@var{rxcookie} 2364@itemx txcookie=@var{txcookie} 2365 Cookies are a weak form of security in the l2tpv3 specification. 2366Their function is mostly to prevent misconfiguration. By default they are 32 2367bit. 2368@item cookie64 2369 Set cookie size to 64 bit instead of the default 32 2370@item counter=off 2371 Force a 'cut-down' L2TPv3 with no counter as in 2372draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00 2373@item pincounter=on 2374 Work around broken counter handling in peer. This may also help on 2375networks which have packet reorder. 2376@item offset=@var{offset} 2377 Add an extra offset between header and data 2378 2379For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan 2380on the remote Linux host 1.2.3.4: 2381@example 2382# Setup tunnel on linux host using raw ip as encapsulation 2383# on 1.2.3.4 2384ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \ 2385 encap udp udp_sport 16384 udp_dport 16384 2386ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \ 2387 0xFFFFFFFF peer_session_id 0xFFFFFFFF 2388ifconfig vmtunnel0 mtu 1500 2389ifconfig vmtunnel0 up 2390brctl addif br-lan vmtunnel0 2391 2392 2393# on 4.3.2.1 2394# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter 2395 2396qemu-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 2397 2398 2399@end example 2400 2401@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 2402@itemx -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 2403Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and 2404listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname} 2405and MODE @var{octalmode} to change default ownership and permissions for 2406communication port. This option is only available if QEMU has been compiled 2407with vde support enabled. 2408 2409Example: 2410@example 2411# launch vde switch 2412vde_switch -F -sock /tmp/myswitch 2413# launch QEMU instance 2414qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch 2415@end example 2416 2417@item -netdev hubport,id=@var{id},hubid=@var{hubid} 2418 2419Create a hub port on QEMU "vlan" @var{hubid}. 2420 2421The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single 2422netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the 2423required hub automatically. 2424 2425@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n] 2426 2427Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should 2428be a unix domain socket backed one. The vhost-user uses a specifically defined 2429protocol to pass vhost ioctl replacement messages to an application on the other 2430end of the socket. On non-MSIX guests, the feature can be forced with 2431@var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to 2432be created for multiqueue vhost-user. 2433 2434Example: 2435@example 2436qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \ 2437 -numa node,memdev=mem \ 2438 -chardev socket,id=chr0,path=/path/to/socket \ 2439 -netdev type=vhost-user,id=net0,chardev=chr0 \ 2440 -device virtio-net-pci,netdev=net0 2441@end example 2442 2443@item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}] 2444Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default). 2445At most @var{len} bytes (64k by default) per packet are stored. The file format is 2446libpcap, so it can be analyzed with tools such as tcpdump or Wireshark. 2447Note: For devices created with '-netdev', use '-object filter-dump,...' instead. 2448 2449@item -net none 2450Indicate that no network devices should be configured. It is used to 2451override the default configuration (@option{-net nic -net user}) which 2452is activated if no @option{-net} options are provided. 2453ETEXI 2454 2455STEXI 2456@end table 2457ETEXI 2458DEFHEADING() 2459 2460DEFHEADING(Character device options) 2461STEXI 2462 2463The general form of a character device option is: 2464@table @option 2465ETEXI 2466 2467DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, 2468 "-chardev help\n" 2469 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2470 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n" 2471 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n" 2472 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n" 2473 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n" 2474 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n" 2475 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" 2476 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n" 2477 " [,logfile=PATH][,logappend=on|off]\n" 2478 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2479 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n" 2480 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2481 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n" 2482 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2483 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2484#ifdef _WIN32 2485 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2486 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2487#else 2488 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2489 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n" 2490#endif 2491#ifdef CONFIG_BRLAPI 2492 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2493#endif 2494#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 2495 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) 2496 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2497 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2498#endif 2499#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) 2500 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2501 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2502#endif 2503#if defined(CONFIG_SPICE) 2504 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2505 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2506#endif 2507 , QEMU_ARCH_ALL 2508) 2509 2510STEXI 2511@item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}] 2512@findex -chardev 2513Backend is one of: 2514@option{null}, 2515@option{socket}, 2516@option{udp}, 2517@option{msmouse}, 2518@option{vc}, 2519@option{ringbuf}, 2520@option{file}, 2521@option{pipe}, 2522@option{console}, 2523@option{serial}, 2524@option{pty}, 2525@option{stdio}, 2526@option{braille}, 2527@option{tty}, 2528@option{parallel}, 2529@option{parport}, 2530@option{spicevmc}. 2531@option{spiceport}. 2532The specific backend will determine the applicable options. 2533 2534Use "-chardev help" to print all available chardev backend types. 2535 2536All devices must have an id, which can be any string up to 127 characters long. 2537It is used to uniquely identify this device in other command line directives. 2538 2539A character device may be used in multiplexing mode by multiple front-ends. 2540Specify @option{mux=on} to enable this mode. 2541A multiplexer is a "1:N" device, and here the "1" end is your specified chardev 2542backend, and the "N" end is the various parts of QEMU that can talk to a chardev. 2543If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will 2544create a multiplexer with your specified ID, and you can then configure multiple 2545front ends to use that chardev ID for their input/output. Up to four different 2546front ends can be connected to a single multiplexed chardev. (Without 2547multiplexing enabled, a chardev can only be used by a single front end.) 2548For instance you could use this to allow a single stdio chardev to be used by 2549two serial ports and the QEMU monitor: 2550 2551@example 2552-chardev stdio,mux=on,id=char0 \ 2553-mon chardev=char0,mode=readline \ 2554-serial chardev:char0 \ 2555-serial chardev:char0 2556@end example 2557 2558You can have more than one multiplexer in a system configuration; for instance 2559you could have a TCP port multiplexed between UART 0 and UART 1, and stdio 2560multiplexed between the QEMU monitor and a parallel port: 2561 2562@example 2563-chardev stdio,mux=on,id=char0 \ 2564-mon chardev=char0,mode=readline \ 2565-parallel chardev:char0 \ 2566-chardev tcp,...,mux=on,id=char1 \ 2567-serial chardev:char1 \ 2568-serial chardev:char1 2569@end example 2570 2571When you're using a multiplexed character device, some escape sequences are 2572interpreted in the input. @xref{mux_keys, Keys in the character backend 2573multiplexer}. 2574 2575Note that some other command line options may implicitly create multiplexed 2576character backends; for instance @option{-serial mon:stdio} creates a 2577multiplexed stdio backend connected to the serial port and the QEMU monitor, 2578and @option{-nographic} also multiplexes the console and the monitor to 2579stdio. 2580 2581There is currently no support for multiplexing in the other direction 2582(where a single QEMU front end takes input and output from multiple chardevs). 2583 2584Every backend supports the @option{logfile} option, which supplies the path 2585to a file to record all data transmitted via the backend. The @option{logappend} 2586option controls whether the log file will be truncated or appended to when 2587opened. 2588 2589Further options to each backend are described below. 2590 2591@item -chardev null ,id=@var{id} 2592A void device. This device will not emit any data, and will drop any data it 2593receives. The null backend does not take any options. 2594 2595@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}] [,tls-creds=@var{id}] 2596 2597Create a two-way stream socket, which can be either a TCP or a unix socket. A 2598unix socket will be created if @option{path} is specified. Behaviour is 2599undefined if TCP options are specified for a unix socket. 2600 2601@option{server} specifies that the socket shall be a listening socket. 2602 2603@option{nowait} specifies that QEMU should not block waiting for a client to 2604connect to a listening socket. 2605 2606@option{telnet} specifies that traffic on the socket should interpret telnet 2607escape sequences. 2608 2609@option{reconnect} sets the timeout for reconnecting on non-server sockets when 2610the remote end goes away. qemu will delay this many seconds and then attempt 2611to reconnect. Zero disables reconnecting, and is the default. 2612 2613@option{tls-creds} requests enablement of the TLS protocol for encryption, 2614and specifies the id of the TLS credentials to use for the handshake. The 2615credentials must be previously created with the @option{-object tls-creds} 2616argument. 2617 2618TCP and unix socket options are given below: 2619 2620@table @option 2621 2622@item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay] 2623 2624@option{host} for a listening socket specifies the local address to be bound. 2625For a connecting socket species the remote host to connect to. @option{host} is 2626optional for listening sockets. If not specified it defaults to @code{0.0.0.0}. 2627 2628@option{port} for a listening socket specifies the local port to be bound. For a 2629connecting socket specifies the port on the remote host to connect to. 2630@option{port} can be given as either a port number or a service name. 2631@option{port} is required. 2632 2633@option{to} is only relevant to listening sockets. If it is specified, and 2634@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up 2635to and including @option{to} until it succeeds. @option{to} must be specified 2636as a port number. 2637 2638@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2639If neither is specified the socket may use either protocol. 2640 2641@option{nodelay} disables the Nagle algorithm. 2642 2643@item unix options: path=@var{path} 2644 2645@option{path} specifies the local path of the unix socket. @option{path} is 2646required. 2647 2648@end table 2649 2650@item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6] 2651 2652Sends all traffic from the guest to a remote host over UDP. 2653 2654@option{host} specifies the remote host to connect to. If not specified it 2655defaults to @code{localhost}. 2656 2657@option{port} specifies the port on the remote host to connect to. @option{port} 2658is required. 2659 2660@option{localaddr} specifies the local address to bind to. If not specified it 2661defaults to @code{0.0.0.0}. 2662 2663@option{localport} specifies the local port to bind to. If not specified any 2664available local port will be used. 2665 2666@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2667If neither is specified the device may use either protocol. 2668 2669@item -chardev msmouse ,id=@var{id} 2670 2671Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not 2672take any options. 2673 2674@item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]] 2675 2676Connect to a QEMU text console. @option{vc} may optionally be given a specific 2677size. 2678 2679@option{width} and @option{height} specify the width and height respectively of 2680the console, in pixels. 2681 2682@option{cols} and @option{rows} specify that the console be sized to fit a text 2683console with the given dimensions. 2684 2685@item -chardev ringbuf ,id=@var{id} [,size=@var{size}] 2686 2687Create a ring buffer with fixed size @option{size}. 2688@var{size} must be a power of two and defaults to @code{64K}. 2689 2690@item -chardev file ,id=@var{id} ,path=@var{path} 2691 2692Log all traffic received from the guest to a file. 2693 2694@option{path} specifies the path of the file to be opened. This file will be 2695created if it does not already exist, and overwritten if it does. @option{path} 2696is required. 2697 2698@item -chardev pipe ,id=@var{id} ,path=@var{path} 2699 2700Create a two-way connection to the guest. The behaviour differs slightly between 2701Windows hosts and other hosts: 2702 2703On Windows, a single duplex pipe will be created at 2704@file{\\.pipe\@option{path}}. 2705 2706On other hosts, 2 pipes will be created called @file{@option{path}.in} and 2707@file{@option{path}.out}. Data written to @file{@option{path}.in} will be 2708received by the guest. Data written by the guest can be read from 2709@file{@option{path}.out}. QEMU will not create these fifos, and requires them to 2710be present. 2711 2712@option{path} forms part of the pipe path as described above. @option{path} is 2713required. 2714 2715@item -chardev console ,id=@var{id} 2716 2717Send traffic from the guest to QEMU's standard output. @option{console} does not 2718take any options. 2719 2720@option{console} is only available on Windows hosts. 2721 2722@item -chardev serial ,id=@var{id} ,path=@option{path} 2723 2724Send traffic from the guest to a serial device on the host. 2725 2726On Unix hosts serial will actually accept any tty device, 2727not only serial lines. 2728 2729@option{path} specifies the name of the serial device to open. 2730 2731@item -chardev pty ,id=@var{id} 2732 2733Create a new pseudo-terminal on the host and connect to it. @option{pty} does 2734not take any options. 2735 2736@option{pty} is not available on Windows hosts. 2737 2738@item -chardev stdio ,id=@var{id} [,signal=on|off] 2739Connect to standard input and standard output of the QEMU process. 2740 2741@option{signal} controls if signals are enabled on the terminal, that includes 2742exiting QEMU with the key sequence @key{Control-c}. This option is enabled by 2743default, use @option{signal=off} to disable it. 2744 2745@item -chardev braille ,id=@var{id} 2746 2747Connect to a local BrlAPI server. @option{braille} does not take any options. 2748 2749@item -chardev tty ,id=@var{id} ,path=@var{path} 2750 2751@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and 2752DragonFlyBSD hosts. It is an alias for @option{serial}. 2753 2754@option{path} specifies the path to the tty. @option{path} is required. 2755 2756@item -chardev parallel ,id=@var{id} ,path=@var{path} 2757@itemx -chardev parport ,id=@var{id} ,path=@var{path} 2758 2759@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts. 2760 2761Connect to a local parallel port. 2762 2763@option{path} specifies the path to the parallel port device. @option{path} is 2764required. 2765 2766@item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name} 2767 2768@option{spicevmc} is only available when spice support is built in. 2769 2770@option{debug} debug level for spicevmc 2771 2772@option{name} name of spice channel to connect to 2773 2774Connect to a spice virtual machine channel, such as vdiport. 2775 2776@item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name} 2777 2778@option{spiceport} is only available when spice support is built in. 2779 2780@option{debug} debug level for spicevmc 2781 2782@option{name} name of spice port to connect to 2783 2784Connect to a spice port, allowing a Spice client to handle the traffic 2785identified by a name (preferably a fqdn). 2786ETEXI 2787 2788STEXI 2789@end table 2790ETEXI 2791DEFHEADING() 2792 2793DEFHEADING(Device URL Syntax) 2794STEXI 2795 2796In addition to using normal file images for the emulated storage devices, 2797QEMU can also use networked resources such as iSCSI devices. These are 2798specified using a special URL syntax. 2799 2800@table @option 2801@item iSCSI 2802iSCSI support allows QEMU to access iSCSI resources directly and use as 2803images for the guest storage. Both disk and cdrom images are supported. 2804 2805Syntax for specifying iSCSI LUNs is 2806``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>'' 2807 2808By default qemu will use the iSCSI initiator-name 2809'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command 2810line or a configuration file. 2811 2812Since version Qemu 2.4 it is possible to specify a iSCSI request timeout to detect 2813stalled requests and force a reestablishment of the session. The timeout 2814is specified in seconds. The default is 0 which means no timeout. Libiscsi 28151.15.0 or greater is required for this feature. 2816 2817Example (without authentication): 2818@example 2819qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \ 2820 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \ 2821 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 2822@end example 2823 2824Example (CHAP username/password via URL): 2825@example 2826qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1 2827@end example 2828 2829Example (CHAP username/password via environment variables): 2830@example 2831LIBISCSI_CHAP_USERNAME="user" \ 2832LIBISCSI_CHAP_PASSWORD="password" \ 2833qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 2834@end example 2835 2836iSCSI support is an optional feature of QEMU and only available when 2837compiled and linked against libiscsi. 2838ETEXI 2839DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi, 2840 "-iscsi [user=user][,password=password]\n" 2841 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n" 2842 " [,initiator-name=initiator-iqn][,id=target-iqn]\n" 2843 " [,timeout=timeout]\n" 2844 " iSCSI session parameters\n", QEMU_ARCH_ALL) 2845STEXI 2846 2847iSCSI parameters such as username and password can also be specified via 2848a configuration file. See qemu-doc for more information and examples. 2849 2850@item NBD 2851QEMU supports NBD (Network Block Devices) both using TCP protocol as well 2852as Unix Domain Sockets. 2853 2854Syntax for specifying a NBD device using TCP 2855``nbd:<server-ip>:<port>[:exportname=<export>]'' 2856 2857Syntax for specifying a NBD device using Unix Domain Sockets 2858``nbd:unix:<domain-socket>[:exportname=<export>]'' 2859 2860 2861Example for TCP 2862@example 2863qemu-system-i386 --drive file=nbd:192.0.2.1:30000 2864@end example 2865 2866Example for Unix Domain Sockets 2867@example 2868qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket 2869@end example 2870 2871@item SSH 2872QEMU supports SSH (Secure Shell) access to remote disks. 2873 2874Examples: 2875@example 2876qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img 2877qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img 2878@end example 2879 2880Currently authentication must be done using ssh-agent. Other 2881authentication methods may be supported in future. 2882 2883@item Sheepdog 2884Sheepdog is a distributed storage system for QEMU. 2885QEMU supports using either local sheepdog devices or remote networked 2886devices. 2887 2888Syntax for specifying a sheepdog device 2889@example 2890sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag] 2891@end example 2892 2893Example 2894@example 2895qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine 2896@end example 2897 2898See also @url{https://sheepdog.github.io/sheepdog/}. 2899 2900@item GlusterFS 2901GlusterFS is a user space distributed file system. 2902QEMU supports the use of GlusterFS volumes for hosting VM disk images using 2903TCP, Unix Domain Sockets and RDMA transport protocols. 2904 2905Syntax for specifying a VM disk image on GlusterFS volume is 2906@example 2907 2908URI: 2909gluster[+type]://[host[:port]]/volume/path[?socket=...][,debug=N][,logfile=...] 2910 2911JSON: 2912'json:@{"driver":"qcow2","file":@{"driver":"gluster","volume":"testvol","path":"a.img","debug":N,"logfile":"...", 2913@ "server":[@{"type":"tcp","host":"...","port":"..."@}, 2914@ @{"type":"unix","socket":"..."@}]@}@}' 2915@end example 2916 2917 2918Example 2919@example 2920URI: 2921qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img, 2922@ file.debug=9,file.logfile=/var/log/qemu-gluster.log 2923 2924JSON: 2925qemu-system-x86_64 'json:@{"driver":"qcow2", 2926@ "file":@{"driver":"gluster", 2927@ "volume":"testvol","path":"a.img", 2928@ "debug":9,"logfile":"/var/log/qemu-gluster.log", 2929@ "server":[@{"type":"tcp","host":"1.2.3.4","port":24007@}, 2930@ @{"type":"unix","socket":"/var/run/glusterd.socket"@}]@}@}' 2931qemu-system-x86_64 -drive driver=qcow2,file.driver=gluster,file.volume=testvol,file.path=/path/a.img, 2932@ file.debug=9,file.logfile=/var/log/qemu-gluster.log, 2933@ file.server.0.type=tcp,file.server.0.host=1.2.3.4,file.server.0.port=24007, 2934@ file.server.1.type=unix,file.server.1.socket=/var/run/glusterd.socket 2935@end example 2936 2937See also @url{http://www.gluster.org}. 2938 2939@item HTTP/HTTPS/FTP/FTPS 2940QEMU supports read-only access to files accessed over http(s) and ftp(s). 2941 2942Syntax using a single filename: 2943@example 2944<protocol>://[<username>[:<password>]@@]<host>/<path> 2945@end example 2946 2947where: 2948@table @option 2949@item protocol 2950'http', 'https', 'ftp', or 'ftps'. 2951 2952@item username 2953Optional username for authentication to the remote server. 2954 2955@item password 2956Optional password for authentication to the remote server. 2957 2958@item host 2959Address of the remote server. 2960 2961@item path 2962Path on the remote server, including any query string. 2963@end table 2964 2965The following options are also supported: 2966@table @option 2967@item url 2968The full URL when passing options to the driver explicitly. 2969 2970@item readahead 2971The amount of data to read ahead with each range request to the remote server. 2972This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it 2973does not have a suffix, it will be assumed to be in bytes. The value must be a 2974multiple of 512 bytes. It defaults to 256k. 2975 2976@item sslverify 2977Whether to verify the remote server's certificate when connecting over SSL. It 2978can have the value 'on' or 'off'. It defaults to 'on'. 2979 2980@item cookie 2981Send this cookie (it can also be a list of cookies separated by ';') with 2982each outgoing request. Only supported when using protocols such as HTTP 2983which support cookies, otherwise ignored. 2984 2985@item timeout 2986Set the timeout in seconds of the CURL connection. This timeout is the time 2987that CURL waits for a response from the remote server to get the size of the 2988image to be downloaded. If not set, the default timeout of 5 seconds is used. 2989@end table 2990 2991Note that when passing options to qemu explicitly, @option{driver} is the value 2992of <protocol>. 2993 2994Example: boot from a remote Fedora 20 live ISO image 2995@example 2996qemu-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 2997 2998qemu-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 2999@end example 3000 3001Example: boot from a remote Fedora 20 cloud image using a local overlay for 3002writes, copy-on-read, and a readahead of 64k 3003@example 3004qemu-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 3005 3006qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on 3007@end example 3008 3009Example: boot from an image stored on a VMware vSphere server with a self-signed 3010certificate using a local overlay for writes, a readahead of 64k and a timeout 3011of 10 seconds. 3012@example 3013qemu-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 3014 3015qemu-system-x86_64 -drive file=/tmp/test.qcow2 3016@end example 3017ETEXI 3018 3019STEXI 3020@end table 3021ETEXI 3022 3023DEFHEADING(Bluetooth(R) options) 3024STEXI 3025@table @option 3026ETEXI 3027 3028DEF("bt", HAS_ARG, QEMU_OPTION_bt, \ 3029 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \ 3030 "-bt hci,host[:id]\n" \ 3031 " use host's HCI with the given name\n" \ 3032 "-bt hci[,vlan=n]\n" \ 3033 " emulate a standard HCI in virtual scatternet 'n'\n" \ 3034 "-bt vhci[,vlan=n]\n" \ 3035 " add host computer to virtual scatternet 'n' using VHCI\n" \ 3036 "-bt device:dev[,vlan=n]\n" \ 3037 " emulate a bluetooth device 'dev' in scatternet 'n'\n", 3038 QEMU_ARCH_ALL) 3039STEXI 3040@item -bt hci[...] 3041@findex -bt 3042Defines the function of the corresponding Bluetooth HCI. -bt options 3043are matched with the HCIs present in the chosen machine type. For 3044example when emulating a machine with only one HCI built into it, only 3045the first @code{-bt hci[...]} option is valid and defines the HCI's 3046logic. The Transport Layer is decided by the machine type. Currently 3047the machines @code{n800} and @code{n810} have one HCI and all other 3048machines have none. 3049 3050@anchor{bt-hcis} 3051The following three types are recognized: 3052 3053@table @option 3054@item -bt hci,null 3055(default) The corresponding Bluetooth HCI assumes no internal logic 3056and will not respond to any HCI commands or emit events. 3057 3058@item -bt hci,host[:@var{id}] 3059(@code{bluez} only) The corresponding HCI passes commands / events 3060to / from the physical HCI identified by the name @var{id} (default: 3061@code{hci0}) on the computer running QEMU. Only available on @code{bluez} 3062capable systems like Linux. 3063 3064@item -bt hci[,vlan=@var{n}] 3065Add a virtual, standard HCI that will participate in the Bluetooth 3066scatternet @var{n} (default @code{0}). Similarly to @option{-net} 3067VLANs, devices inside a bluetooth network @var{n} can only communicate 3068with other devices in the same network (scatternet). 3069@end table 3070 3071@item -bt vhci[,vlan=@var{n}] 3072(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached 3073to the host bluetooth stack instead of to the emulated target. This 3074allows the host and target machines to participate in a common scatternet 3075and communicate. Requires the Linux @code{vhci} driver installed. Can 3076be used as following: 3077 3078@example 3079qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5 3080@end example 3081 3082@item -bt device:@var{dev}[,vlan=@var{n}] 3083Emulate a bluetooth device @var{dev} and place it in network @var{n} 3084(default @code{0}). QEMU can only emulate one type of bluetooth devices 3085currently: 3086 3087@table @option 3088@item keyboard 3089Virtual wireless keyboard implementing the HIDP bluetooth profile. 3090@end table 3091ETEXI 3092 3093STEXI 3094@end table 3095ETEXI 3096DEFHEADING() 3097 3098#ifdef CONFIG_TPM 3099DEFHEADING(TPM device options) 3100 3101DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \ 3102 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n" 3103 " use path to provide path to a character device; default is /dev/tpm0\n" 3104 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n" 3105 " not provided it will be searched for in /sys/class/misc/tpm?/device\n", 3106 QEMU_ARCH_ALL) 3107STEXI 3108 3109The general form of a TPM device option is: 3110@table @option 3111 3112@item -tpmdev @var{backend} ,id=@var{id} [,@var{options}] 3113@findex -tpmdev 3114Backend type must be: 3115@option{passthrough}. 3116 3117The specific backend type will determine the applicable options. 3118The @code{-tpmdev} option creates the TPM backend and requires a 3119@code{-device} option that specifies the TPM frontend interface model. 3120 3121Options to each backend are described below. 3122 3123Use 'help' to print all available TPM backend types. 3124@example 3125qemu -tpmdev help 3126@end example 3127 3128@item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path} 3129 3130(Linux-host only) Enable access to the host's TPM using the passthrough 3131driver. 3132 3133@option{path} specifies the path to the host's TPM device, i.e., on 3134a Linux host this would be @code{/dev/tpm0}. 3135@option{path} is optional and by default @code{/dev/tpm0} is used. 3136 3137@option{cancel-path} specifies the path to the host TPM device's sysfs 3138entry allowing for cancellation of an ongoing TPM command. 3139@option{cancel-path} is optional and by default QEMU will search for the 3140sysfs entry to use. 3141 3142Some notes about using the host's TPM with the passthrough driver: 3143 3144The TPM device accessed by the passthrough driver must not be 3145used by any other application on the host. 3146 3147Since the host's firmware (BIOS/UEFI) has already initialized the TPM, 3148the VM's firmware (BIOS/UEFI) will not be able to initialize the 3149TPM again and may therefore not show a TPM-specific menu that would 3150otherwise allow the user to configure the TPM, e.g., allow the user to 3151enable/disable or activate/deactivate the TPM. 3152Further, if TPM ownership is released from within a VM then the host's TPM 3153will get disabled and deactivated. To enable and activate the 3154TPM again afterwards, the host has to be rebooted and the user is 3155required to enter the firmware's menu to enable and activate the TPM. 3156If the TPM is left disabled and/or deactivated most TPM commands will fail. 3157 3158To create a passthrough TPM use the following two options: 3159@example 3160-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0 3161@end example 3162Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by 3163@code{tpmdev=tpm0} in the device option. 3164 3165@end table 3166 3167ETEXI 3168 3169DEFHEADING() 3170 3171#endif 3172 3173DEFHEADING(Linux/Multiboot boot specific) 3174STEXI 3175 3176When using these options, you can use a given Linux or Multiboot 3177kernel without installing it in the disk image. It can be useful 3178for easier testing of various kernels. 3179 3180@table @option 3181ETEXI 3182 3183DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \ 3184 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL) 3185STEXI 3186@item -kernel @var{bzImage} 3187@findex -kernel 3188Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel 3189or in multiboot format. 3190ETEXI 3191 3192DEF("append", HAS_ARG, QEMU_OPTION_append, \ 3193 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL) 3194STEXI 3195@item -append @var{cmdline} 3196@findex -append 3197Use @var{cmdline} as kernel command line 3198ETEXI 3199 3200DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \ 3201 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL) 3202STEXI 3203@item -initrd @var{file} 3204@findex -initrd 3205Use @var{file} as initial ram disk. 3206 3207@item -initrd "@var{file1} arg=foo,@var{file2}" 3208 3209This syntax is only available with multiboot. 3210 3211Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the 3212first module. 3213ETEXI 3214 3215DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \ 3216 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL) 3217STEXI 3218@item -dtb @var{file} 3219@findex -dtb 3220Use @var{file} as a device tree binary (dtb) image and pass it to the kernel 3221on boot. 3222ETEXI 3223 3224STEXI 3225@end table 3226ETEXI 3227DEFHEADING() 3228 3229DEFHEADING(Debug/Expert options) 3230STEXI 3231@table @option 3232ETEXI 3233 3234DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg, 3235 "-fw_cfg [name=]<name>,file=<file>\n" 3236 " add named fw_cfg entry with contents from file\n" 3237 "-fw_cfg [name=]<name>,string=<str>\n" 3238 " add named fw_cfg entry with contents from string\n", 3239 QEMU_ARCH_ALL) 3240STEXI 3241 3242@item -fw_cfg [name=]@var{name},file=@var{file} 3243@findex -fw_cfg 3244Add named fw_cfg entry with contents from file @var{file}. 3245 3246@item -fw_cfg [name=]@var{name},string=@var{str} 3247Add named fw_cfg entry with contents from string @var{str}. 3248 3249The terminating NUL character of the contents of @var{str} will not be 3250included as part of the fw_cfg item data. To insert contents with 3251embedded NUL characters, you have to use the @var{file} parameter. 3252 3253The fw_cfg entries are passed by QEMU through to the guest. 3254 3255Example: 3256@example 3257 -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin 3258@end example 3259creates an fw_cfg entry named opt/com.mycompany/blob with contents 3260from ./my_blob.bin. 3261 3262ETEXI 3263 3264DEF("serial", HAS_ARG, QEMU_OPTION_serial, \ 3265 "-serial dev redirect the serial port to char device 'dev'\n", 3266 QEMU_ARCH_ALL) 3267STEXI 3268@item -serial @var{dev} 3269@findex -serial 3270Redirect the virtual serial port to host character device 3271@var{dev}. The default device is @code{vc} in graphical mode and 3272@code{stdio} in non graphical mode. 3273 3274This option can be used several times to simulate up to 4 serial 3275ports. 3276 3277Use @code{-serial none} to disable all serial ports. 3278 3279Available character devices are: 3280@table @option 3281@item vc[:@var{W}x@var{H}] 3282Virtual console. Optionally, a width and height can be given in pixel with 3283@example 3284vc:800x600 3285@end example 3286It is also possible to specify width or height in characters: 3287@example 3288vc:80Cx24C 3289@end example 3290@item pty 3291[Linux only] Pseudo TTY (a new PTY is automatically allocated) 3292@item none 3293No device is allocated. 3294@item null 3295void device 3296@item chardev:@var{id} 3297Use a named character device defined with the @code{-chardev} option. 3298@item /dev/XXX 3299[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port 3300parameters are set according to the emulated ones. 3301@item /dev/parport@var{N} 3302[Linux only, parallel port only] Use host parallel port 3303@var{N}. Currently SPP and EPP parallel port features can be used. 3304@item file:@var{filename} 3305Write output to @var{filename}. No character can be read. 3306@item stdio 3307[Unix only] standard input/output 3308@item pipe:@var{filename} 3309name pipe @var{filename} 3310@item COM@var{n} 3311[Windows only] Use host serial port @var{n} 3312@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}] 3313This implements UDP Net Console. 3314When @var{remote_host} or @var{src_ip} are not specified 3315they default to @code{0.0.0.0}. 3316When not using a specified @var{src_port} a random port is automatically chosen. 3317 3318If you just want a simple readonly console you can use @code{netcat} or 3319@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as: 3320@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it 3321will appear in the netconsole session. 3322 3323If you plan to send characters back via netconsole or you want to stop 3324and start QEMU a lot of times, you should have QEMU use the same 3325source port each time by using something like @code{-serial 3326udp::4555@@:4556} to QEMU. Another approach is to use a patched 3327version of netcat which can listen to a TCP port and send and receive 3328characters via udp. If you have a patched version of netcat which 3329activates telnet remote echo and single char transfer, then you can 3330use the following options to set up a netcat redirector to allow 3331telnet on port 5555 to access the QEMU port. 3332@table @code 3333@item QEMU Options: 3334-serial udp::4555@@:4556 3335@item netcat options: 3336-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T 3337@item telnet options: 3338localhost 5555 3339@end table 3340 3341@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}] 3342The TCP Net Console has two modes of operation. It can send the serial 3343I/O to a location or wait for a connection from a location. By default 3344the TCP Net Console is sent to @var{host} at the @var{port}. If you use 3345the @var{server} option QEMU will wait for a client socket application 3346to connect to the port before continuing, unless the @code{nowait} 3347option was specified. The @code{nodelay} option disables the Nagle buffering 3348algorithm. The @code{reconnect} option only applies if @var{noserver} is 3349set, if the connection goes down it will attempt to reconnect at the 3350given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only 3351one TCP connection at a time is accepted. You can use @code{telnet} to 3352connect to the corresponding character device. 3353@table @code 3354@item Example to send tcp console to 192.168.0.2 port 4444 3355-serial tcp:192.168.0.2:4444 3356@item Example to listen and wait on port 4444 for connection 3357-serial tcp::4444,server 3358@item Example to not wait and listen on ip 192.168.0.100 port 4444 3359-serial tcp:192.168.0.100:4444,server,nowait 3360@end table 3361 3362@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay] 3363The telnet protocol is used instead of raw tcp sockets. The options 3364work the same as if you had specified @code{-serial tcp}. The 3365difference is that the port acts like a telnet server or client using 3366telnet option negotiation. This will also allow you to send the 3367MAGIC_SYSRQ sequence if you use a telnet that supports sending the break 3368sequence. Typically in unix telnet you do it with Control-] and then 3369type "send break" followed by pressing the enter key. 3370 3371@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}] 3372A unix domain socket is used instead of a tcp socket. The option works the 3373same as if you had specified @code{-serial tcp} except the unix domain socket 3374@var{path} is used for connections. 3375 3376@item mon:@var{dev_string} 3377This is a special option to allow the monitor to be multiplexed onto 3378another serial port. The monitor is accessed with key sequence of 3379@key{Control-a} and then pressing @key{c}. 3380@var{dev_string} should be any one of the serial devices specified 3381above. An example to multiplex the monitor onto a telnet server 3382listening on port 4444 would be: 3383@table @code 3384@item -serial mon:telnet::4444,server,nowait 3385@end table 3386When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate 3387QEMU any more but will be passed to the guest instead. 3388 3389@item braille 3390Braille device. This will use BrlAPI to display the braille output on a real 3391or fake device. 3392 3393@item msmouse 3394Three button serial mouse. Configure the guest to use Microsoft protocol. 3395@end table 3396ETEXI 3397 3398DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \ 3399 "-parallel dev redirect the parallel port to char device 'dev'\n", 3400 QEMU_ARCH_ALL) 3401STEXI 3402@item -parallel @var{dev} 3403@findex -parallel 3404Redirect the virtual parallel port to host device @var{dev} (same 3405devices as the serial port). On Linux hosts, @file{/dev/parportN} can 3406be used to use hardware devices connected on the corresponding host 3407parallel port. 3408 3409This option can be used several times to simulate up to 3 parallel 3410ports. 3411 3412Use @code{-parallel none} to disable all parallel ports. 3413ETEXI 3414 3415DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \ 3416 "-monitor dev redirect the monitor to char device 'dev'\n", 3417 QEMU_ARCH_ALL) 3418STEXI 3419@item -monitor @var{dev} 3420@findex -monitor 3421Redirect the monitor to host device @var{dev} (same devices as the 3422serial port). 3423The default device is @code{vc} in graphical mode and @code{stdio} in 3424non graphical mode. 3425Use @code{-monitor none} to disable the default monitor. 3426ETEXI 3427DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \ 3428 "-qmp dev like -monitor but opens in 'control' mode\n", 3429 QEMU_ARCH_ALL) 3430STEXI 3431@item -qmp @var{dev} 3432@findex -qmp 3433Like -monitor but opens in 'control' mode. 3434ETEXI 3435DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \ 3436 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n", 3437 QEMU_ARCH_ALL) 3438STEXI 3439@item -qmp-pretty @var{dev} 3440@findex -qmp-pretty 3441Like -qmp but uses pretty JSON formatting. 3442ETEXI 3443 3444DEF("mon", HAS_ARG, QEMU_OPTION_mon, \ 3445 "-mon [chardev=]name[,mode=readline|control]\n", QEMU_ARCH_ALL) 3446STEXI 3447@item -mon [chardev=]name[,mode=readline|control] 3448@findex -mon 3449Setup monitor on chardev @var{name}. 3450ETEXI 3451 3452DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ 3453 "-debugcon dev redirect the debug console to char device 'dev'\n", 3454 QEMU_ARCH_ALL) 3455STEXI 3456@item -debugcon @var{dev} 3457@findex -debugcon 3458Redirect the debug console to host device @var{dev} (same devices as the 3459serial port). The debug console is an I/O port which is typically port 34600xe9; writing to that I/O port sends output to this device. 3461The default device is @code{vc} in graphical mode and @code{stdio} in 3462non graphical mode. 3463ETEXI 3464 3465DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ 3466 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL) 3467STEXI 3468@item -pidfile @var{file} 3469@findex -pidfile 3470Store the QEMU process PID in @var{file}. It is useful if you launch QEMU 3471from a script. 3472ETEXI 3473 3474DEF("singlestep", 0, QEMU_OPTION_singlestep, \ 3475 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) 3476STEXI 3477@item -singlestep 3478@findex -singlestep 3479Run the emulation in single step mode. 3480ETEXI 3481 3482DEF("S", 0, QEMU_OPTION_S, \ 3483 "-S freeze CPU at startup (use 'c' to start execution)\n", 3484 QEMU_ARCH_ALL) 3485STEXI 3486@item -S 3487@findex -S 3488Do not start CPU at startup (you must type 'c' in the monitor). 3489ETEXI 3490 3491DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, 3492 "-realtime [mlock=on|off]\n" 3493 " run qemu with realtime features\n" 3494 " mlock=on|off controls mlock support (default: on)\n", 3495 QEMU_ARCH_ALL) 3496STEXI 3497@item -realtime mlock=on|off 3498@findex -realtime 3499Run qemu with realtime features. 3500mlocking qemu and guest memory can be enabled via @option{mlock=on} 3501(enabled by default). 3502ETEXI 3503 3504DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ 3505 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) 3506STEXI 3507@item -gdb @var{dev} 3508@findex -gdb 3509Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical 3510connections will likely be TCP-based, but also UDP, pseudo TTY, or even 3511stdio are reasonable use case. The latter is allowing to start QEMU from 3512within gdb and establish the connection via a pipe: 3513@example 3514(gdb) target remote | exec qemu-system-i386 -gdb stdio ... 3515@end example 3516ETEXI 3517 3518DEF("s", 0, QEMU_OPTION_s, \ 3519 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n", 3520 QEMU_ARCH_ALL) 3521STEXI 3522@item -s 3523@findex -s 3524Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234 3525(@pxref{gdb_usage}). 3526ETEXI 3527 3528DEF("d", HAS_ARG, QEMU_OPTION_d, \ 3529 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n", 3530 QEMU_ARCH_ALL) 3531STEXI 3532@item -d @var{item1}[,...] 3533@findex -d 3534Enable logging of specified items. Use '-d help' for a list of log items. 3535ETEXI 3536 3537DEF("D", HAS_ARG, QEMU_OPTION_D, \ 3538 "-D logfile output log to logfile (default stderr)\n", 3539 QEMU_ARCH_ALL) 3540STEXI 3541@item -D @var{logfile} 3542@findex -D 3543Output log in @var{logfile} instead of to stderr 3544ETEXI 3545 3546DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \ 3547 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n", 3548 QEMU_ARCH_ALL) 3549STEXI 3550@item -dfilter @var{range1}[,...] 3551@findex -dfilter 3552Filter debug output to that relevant to a range of target addresses. The filter 3553spec can be either @var{start}+@var{size}, @var{start}-@var{size} or 3554@var{start}..@var{end} where @var{start} @var{end} and @var{size} are the 3555addresses and sizes required. For example: 3556@example 3557 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000 3558@end example 3559Will dump output for any code in the 0x1000 sized block starting at 0x8000 and 3560the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized 3561block starting at 0xffffffc00005f000. 3562ETEXI 3563 3564DEF("L", HAS_ARG, QEMU_OPTION_L, \ 3565 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", 3566 QEMU_ARCH_ALL) 3567STEXI 3568@item -L @var{path} 3569@findex -L 3570Set the directory for the BIOS, VGA BIOS and keymaps. 3571 3572To list all the data directories, use @code{-L help}. 3573ETEXI 3574 3575DEF("bios", HAS_ARG, QEMU_OPTION_bios, \ 3576 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL) 3577STEXI 3578@item -bios @var{file} 3579@findex -bios 3580Set the filename for the BIOS. 3581ETEXI 3582 3583DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \ 3584 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL) 3585STEXI 3586@item -enable-kvm 3587@findex -enable-kvm 3588Enable KVM full virtualization support. This option is only available 3589if KVM support is enabled when compiling. 3590ETEXI 3591 3592DEF("enable-hax", 0, QEMU_OPTION_enable_hax, \ 3593 "-enable-hax enable HAX virtualization support\n", QEMU_ARCH_I386) 3594STEXI 3595@item -enable-hax 3596@findex -enable-hax 3597Enable HAX (Hardware-based Acceleration eXecution) support. This option 3598is only available if HAX support is enabled when compiling. HAX is only 3599applicable to MAC and Windows platform, and thus does not conflict with 3600KVM. 3601ETEXI 3602 3603DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, 3604 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) 3605DEF("xen-create", 0, QEMU_OPTION_xen_create, 3606 "-xen-create create domain using xen hypercalls, bypassing xend\n" 3607 " warning: should not be used when xend is in use\n", 3608 QEMU_ARCH_ALL) 3609DEF("xen-attach", 0, QEMU_OPTION_xen_attach, 3610 "-xen-attach attach to existing xen domain\n" 3611 " xend will use this when starting QEMU\n", 3612 QEMU_ARCH_ALL) 3613DEF("xen-domid-restrict", 0, QEMU_OPTION_xen_domid_restrict, 3614 "-xen-domid-restrict restrict set of available xen operations\n" 3615 " to specified domain id. (Does not affect\n" 3616 " xenpv machine type).\n", 3617 QEMU_ARCH_ALL) 3618STEXI 3619@item -xen-domid @var{id} 3620@findex -xen-domid 3621Specify xen guest domain @var{id} (XEN only). 3622@item -xen-create 3623@findex -xen-create 3624Create domain using xen hypercalls, bypassing xend. 3625Warning: should not be used when xend is in use (XEN only). 3626@item -xen-attach 3627@findex -xen-attach 3628Attach to existing xen domain. 3629xend will use this when starting QEMU (XEN only). 3630@findex -xen-domid-restrict 3631Restrict set of available xen operations to specified domain id (XEN only). 3632ETEXI 3633 3634DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \ 3635 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL) 3636STEXI 3637@item -no-reboot 3638@findex -no-reboot 3639Exit instead of rebooting. 3640ETEXI 3641 3642DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \ 3643 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL) 3644STEXI 3645@item -no-shutdown 3646@findex -no-shutdown 3647Don't exit QEMU on guest shutdown, but instead only stop the emulation. 3648This allows for instance switching to monitor to commit changes to the 3649disk image. 3650ETEXI 3651 3652DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ 3653 "-loadvm [tag|id]\n" \ 3654 " start right away with a saved state (loadvm in monitor)\n", 3655 QEMU_ARCH_ALL) 3656STEXI 3657@item -loadvm @var{file} 3658@findex -loadvm 3659Start right away with a saved state (@code{loadvm} in monitor) 3660ETEXI 3661 3662#ifndef _WIN32 3663DEF("daemonize", 0, QEMU_OPTION_daemonize, \ 3664 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) 3665#endif 3666STEXI 3667@item -daemonize 3668@findex -daemonize 3669Daemonize the QEMU process after initialization. QEMU will not detach from 3670standard IO until it is ready to receive connections on any of its devices. 3671This option is a useful way for external programs to launch QEMU without having 3672to cope with initialization race conditions. 3673ETEXI 3674 3675DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \ 3676 "-option-rom rom load a file, rom, into the option ROM space\n", 3677 QEMU_ARCH_ALL) 3678STEXI 3679@item -option-rom @var{file} 3680@findex -option-rom 3681Load the contents of @var{file} as an option ROM. 3682This option is useful to load things like EtherBoot. 3683ETEXI 3684 3685HXCOMM Silently ignored for compatibility 3686DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL) 3687 3688HXCOMM Options deprecated by -rtc 3689DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL) 3690DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL) 3691 3692DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \ 3693 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \ 3694 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n", 3695 QEMU_ARCH_ALL) 3696 3697STEXI 3698 3699@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew] 3700@findex -rtc 3701Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current 3702UTC or local time, respectively. @code{localtime} is required for correct date in 3703MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the 3704format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC. 3705 3706By default the RTC is driven by the host system time. This allows using of the 3707RTC as accurate reference clock inside the guest, specifically if the host 3708time is smoothly following an accurate external reference clock, e.g. via NTP. 3709If you want to isolate the guest time from the host, you can set @option{clock} 3710to @code{rt} instead. To even prevent it from progressing during suspension, 3711you can set it to @code{vm}. 3712 3713Enable @option{driftfix} (i386 targets only) if you experience time drift problems, 3714specifically with Windows' ACPI HAL. This option will try to figure out how 3715many timer interrupts were not processed by the Windows guest and will 3716re-inject them. 3717ETEXI 3718 3719DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ 3720 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>,rrsnapshot=<snapshot>]\n" \ 3721 " enable virtual instruction counter with 2^N clock ticks per\n" \ 3722 " instruction, enable aligning the host and virtual clocks\n" \ 3723 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL) 3724STEXI 3725@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename},rrsnapshot=@var{snapshot}] 3726@findex -icount 3727Enable virtual instruction counter. The virtual cpu will execute one 3728instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified 3729then the virtual cpu speed will be automatically adjusted to keep virtual 3730time within a few seconds of real time. 3731 3732When the virtual cpu is sleeping, the virtual time will advance at default 3733speed unless @option{sleep=on|off} is specified. 3734With @option{sleep=on|off}, the virtual time will jump to the next timer deadline 3735instantly whenever the virtual cpu goes to sleep mode and will not advance 3736if no timer is enabled. This behavior give deterministic execution times from 3737the guest point of view. 3738 3739Note that while this option can give deterministic behavior, it does not 3740provide cycle accurate emulation. Modern CPUs contain superscalar out of 3741order cores with complex cache hierarchies. The number of instructions 3742executed often has little or no correlation with actual performance. 3743 3744@option{align=on} will activate the delay algorithm which will try 3745to synchronise the host clock and the virtual clock. The goal is to 3746have a guest running at the real frequency imposed by the shift option. 3747Whenever the guest clock is behind the host clock and if 3748@option{align=on} is specified then we print a message to the user 3749to inform about the delay. 3750Currently this option does not work when @option{shift} is @code{auto}. 3751Note: The sync algorithm will work for those shift values for which 3752the guest clock runs ahead of the host clock. Typically this happens 3753when the shift value is high (how high depends on the host machine). 3754 3755When @option{rr} option is specified deterministic record/replay is enabled. 3756Replay log is written into @var{filename} file in record mode and 3757read from this file in replay mode. 3758 3759Option rrsnapshot is used to create new vm snapshot named @var{snapshot} 3760at the start of execution recording. In replay mode this option is used 3761to load the initial VM state. 3762ETEXI 3763 3764DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ 3765 "-watchdog model\n" \ 3766 " enable virtual hardware watchdog [default=none]\n", 3767 QEMU_ARCH_ALL) 3768STEXI 3769@item -watchdog @var{model} 3770@findex -watchdog 3771Create a virtual hardware watchdog device. Once enabled (by a guest 3772action), the watchdog must be periodically polled by an agent inside 3773the guest or else the guest will be restarted. Choose a model for 3774which your guest has drivers. 3775 3776The @var{model} is the model of hardware watchdog to emulate. Use 3777@code{-watchdog help} to list available hardware models. Only one 3778watchdog can be enabled for a guest. 3779 3780The following models may be available: 3781@table @option 3782@item ib700 3783iBASE 700 is a very simple ISA watchdog with a single timer. 3784@item i6300esb 3785Intel 6300ESB I/O controller hub is a much more featureful PCI-based 3786dual-timer watchdog. 3787@item diag288 3788A virtual watchdog for s390x backed by the diagnose 288 hypercall 3789(currently KVM only). 3790@end table 3791ETEXI 3792 3793DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \ 3794 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \ 3795 " action when watchdog fires [default=reset]\n", 3796 QEMU_ARCH_ALL) 3797STEXI 3798@item -watchdog-action @var{action} 3799@findex -watchdog-action 3800 3801The @var{action} controls what QEMU will do when the watchdog timer 3802expires. 3803The default is 3804@code{reset} (forcefully reset the guest). 3805Other possible actions are: 3806@code{shutdown} (attempt to gracefully shutdown the guest), 3807@code{poweroff} (forcefully poweroff the guest), 3808@code{pause} (pause the guest), 3809@code{debug} (print a debug message and continue), or 3810@code{none} (do nothing). 3811 3812Note that the @code{shutdown} action requires that the guest responds 3813to ACPI signals, which it may not be able to do in the sort of 3814situations where the watchdog would have expired, and thus 3815@code{-watchdog-action shutdown} is not recommended for production use. 3816 3817Examples: 3818 3819@table @code 3820@item -watchdog i6300esb -watchdog-action pause 3821@itemx -watchdog ib700 3822@end table 3823ETEXI 3824 3825DEF("echr", HAS_ARG, QEMU_OPTION_echr, \ 3826 "-echr chr set terminal escape character instead of ctrl-a\n", 3827 QEMU_ARCH_ALL) 3828STEXI 3829 3830@item -echr @var{numeric_ascii_value} 3831@findex -echr 3832Change the escape character used for switching to the monitor when using 3833monitor and serial sharing. The default is @code{0x01} when using the 3834@code{-nographic} option. @code{0x01} is equal to pressing 3835@code{Control-a}. You can select a different character from the ascii 3836control keys where 1 through 26 map to Control-a through Control-z. For 3837instance you could use the either of the following to change the escape 3838character to Control-t. 3839@table @code 3840@item -echr 0x14 3841@itemx -echr 20 3842@end table 3843ETEXI 3844 3845DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \ 3846 "-virtioconsole c\n" \ 3847 " set virtio console\n", QEMU_ARCH_ALL) 3848STEXI 3849@item -virtioconsole @var{c} 3850@findex -virtioconsole 3851Set virtio console. 3852 3853This option is maintained for backward compatibility. 3854 3855Please use @code{-device virtconsole} for the new way of invocation. 3856ETEXI 3857 3858DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \ 3859 "-show-cursor show cursor\n", QEMU_ARCH_ALL) 3860STEXI 3861@item -show-cursor 3862@findex -show-cursor 3863Show cursor. 3864ETEXI 3865 3866DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \ 3867 "-tb-size n set TB size\n", QEMU_ARCH_ALL) 3868STEXI 3869@item -tb-size @var{n} 3870@findex -tb-size 3871Set TB size. 3872ETEXI 3873 3874DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \ 3875 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \ 3876 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \ 3877 "-incoming unix:socketpath\n" \ 3878 " prepare for incoming migration, listen on\n" \ 3879 " specified protocol and socket address\n" \ 3880 "-incoming fd:fd\n" \ 3881 "-incoming exec:cmdline\n" \ 3882 " accept incoming migration on given file descriptor\n" \ 3883 " or from given external command\n" \ 3884 "-incoming defer\n" \ 3885 " wait for the URI to be specified via migrate_incoming\n", 3886 QEMU_ARCH_ALL) 3887STEXI 3888@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6] 3889@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6] 3890@findex -incoming 3891Prepare for incoming migration, listen on a given tcp port. 3892 3893@item -incoming unix:@var{socketpath} 3894Prepare for incoming migration, listen on a given unix socket. 3895 3896@item -incoming fd:@var{fd} 3897Accept incoming migration from a given filedescriptor. 3898 3899@item -incoming exec:@var{cmdline} 3900Accept incoming migration as an output from specified external command. 3901 3902@item -incoming defer 3903Wait for the URI to be specified via migrate_incoming. The monitor can 3904be used to change settings (such as migration parameters) prior to issuing 3905the migrate_incoming to allow the migration to begin. 3906ETEXI 3907 3908DEF("only-migratable", 0, QEMU_OPTION_only_migratable, \ 3909 "-only-migratable allow only migratable devices\n", QEMU_ARCH_ALL) 3910STEXI 3911@item -only-migratable 3912@findex -only-migratable 3913Only allow migratable devices. Devices will not be allowed to enter an 3914unmigratable state. 3915ETEXI 3916 3917DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \ 3918 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL) 3919STEXI 3920@item -nodefaults 3921@findex -nodefaults 3922Don't create default devices. Normally, QEMU sets the default devices like serial 3923port, parallel port, virtual console, monitor device, VGA adapter, floppy and 3924CD-ROM drive and others. The @code{-nodefaults} option will disable all those 3925default devices. 3926ETEXI 3927 3928#ifndef _WIN32 3929DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \ 3930 "-chroot dir chroot to dir just before starting the VM\n", 3931 QEMU_ARCH_ALL) 3932#endif 3933STEXI 3934@item -chroot @var{dir} 3935@findex -chroot 3936Immediately before starting guest execution, chroot to the specified 3937directory. Especially useful in combination with -runas. 3938ETEXI 3939 3940#ifndef _WIN32 3941DEF("runas", HAS_ARG, QEMU_OPTION_runas, \ 3942 "-runas user change to user id user just before starting the VM\n", 3943 QEMU_ARCH_ALL) 3944#endif 3945STEXI 3946@item -runas @var{user} 3947@findex -runas 3948Immediately before starting guest execution, drop root privileges, switching 3949to the specified user. 3950ETEXI 3951 3952DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env, 3953 "-prom-env variable=value\n" 3954 " set OpenBIOS nvram variables\n", 3955 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 3956STEXI 3957@item -prom-env @var{variable}=@var{value} 3958@findex -prom-env 3959Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only). 3960ETEXI 3961DEF("semihosting", 0, QEMU_OPTION_semihosting, 3962 "-semihosting semihosting mode\n", 3963 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3964 QEMU_ARCH_MIPS) 3965STEXI 3966@item -semihosting 3967@findex -semihosting 3968Enable semihosting mode (ARM, M68K, Xtensa, MIPS only). 3969ETEXI 3970DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config, 3971 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \ 3972 " semihosting configuration\n", 3973QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3974QEMU_ARCH_MIPS) 3975STEXI 3976@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]] 3977@findex -semihosting-config 3978Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only). 3979@table @option 3980@item target=@code{native|gdb|auto} 3981Defines where the semihosting calls will be addressed, to QEMU (@code{native}) 3982or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb} 3983during debug sessions and @code{native} otherwise. 3984@item arg=@var{str1},arg=@var{str2},... 3985Allows the user to pass input arguments, and can be used multiple times to build 3986up a list. The old-style @code{-kernel}/@code{-append} method of passing a 3987command line is still supported for backward compatibility. If both the 3988@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are 3989specified, the former is passed to semihosting as it always takes precedence. 3990@end table 3991ETEXI 3992DEF("old-param", 0, QEMU_OPTION_old_param, 3993 "-old-param old param mode\n", QEMU_ARCH_ARM) 3994STEXI 3995@item -old-param 3996@findex -old-param (ARM) 3997Old param mode (ARM only). 3998ETEXI 3999 4000DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ 4001 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n", 4002 QEMU_ARCH_ALL) 4003STEXI 4004@item -sandbox @var{arg} 4005@findex -sandbox 4006Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will 4007disable it. The default is 'off'. 4008ETEXI 4009 4010DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, 4011 "-readconfig <file>\n", QEMU_ARCH_ALL) 4012STEXI 4013@item -readconfig @var{file} 4014@findex -readconfig 4015Read device configuration from @var{file}. This approach is useful when you want to spawn 4016QEMU process with many command line options but you don't want to exceed the command line 4017character limit. 4018ETEXI 4019DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig, 4020 "-writeconfig <file>\n" 4021 " read/write config file\n", QEMU_ARCH_ALL) 4022STEXI 4023@item -writeconfig @var{file} 4024@findex -writeconfig 4025Write device configuration to @var{file}. The @var{file} can be either filename to save 4026command line and device configuration into file or dash @code{-}) character to print the 4027output to stdout. This can be later used as input file for @code{-readconfig} option. 4028ETEXI 4029DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, 4030 "-nodefconfig\n" 4031 " do not load default config files at startup\n", 4032 QEMU_ARCH_ALL) 4033STEXI 4034@item -nodefconfig 4035@findex -nodefconfig 4036Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup. 4037The @code{-nodefconfig} option will prevent QEMU from loading any of those config files. 4038ETEXI 4039DEF("no-user-config", 0, QEMU_OPTION_nouserconfig, 4040 "-no-user-config\n" 4041 " do not load user-provided config files at startup\n", 4042 QEMU_ARCH_ALL) 4043STEXI 4044@item -no-user-config 4045@findex -no-user-config 4046The @code{-no-user-config} option makes QEMU not load any of the user-provided 4047config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config 4048files from @var{datadir}. 4049ETEXI 4050DEF("trace", HAS_ARG, QEMU_OPTION_trace, 4051 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 4052 " specify tracing options\n", 4053 QEMU_ARCH_ALL) 4054STEXI 4055HXCOMM This line is not accurate, as some sub-options are backend-specific but 4056HXCOMM HX does not support conditional compilation of text. 4057@item -trace [[enable=]@var{pattern}][,events=@var{file}][,file=@var{file}] 4058@findex -trace 4059@include qemu-option-trace.texi 4060ETEXI 4061 4062HXCOMM Internal use 4063DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL) 4064DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL) 4065 4066#ifdef __linux__ 4067DEF("enable-fips", 0, QEMU_OPTION_enablefips, 4068 "-enable-fips enable FIPS 140-2 compliance\n", 4069 QEMU_ARCH_ALL) 4070#endif 4071STEXI 4072@item -enable-fips 4073@findex -enable-fips 4074Enable FIPS 140-2 compliance mode. 4075ETEXI 4076 4077HXCOMM Deprecated by -machine accel=tcg property 4078DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386) 4079 4080HXCOMM Deprecated by kvm-pit driver properties 4081DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection, 4082 "", QEMU_ARCH_I386) 4083 4084HXCOMM Deprecated (ignored) 4085DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386) 4086 4087HXCOMM Deprecated by -machine kernel_irqchip=on|off property 4088DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386) 4089 4090HXCOMM Deprecated (ignored) 4091DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL) 4092 4093DEF("msg", HAS_ARG, QEMU_OPTION_msg, 4094 "-msg timestamp[=on|off]\n" 4095 " change the format of messages\n" 4096 " on|off controls leading timestamps (default:on)\n", 4097 QEMU_ARCH_ALL) 4098STEXI 4099@item -msg timestamp[=on|off] 4100@findex -msg 4101prepend a timestamp to each log message.(default:on) 4102ETEXI 4103 4104DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate, 4105 "-dump-vmstate <file>\n" 4106 " Output vmstate information in JSON format to file.\n" 4107 " Use the scripts/vmstate-static-checker.py file to\n" 4108 " check for possible regressions in migration code\n" 4109 " by comparing two such vmstate dumps.\n", 4110 QEMU_ARCH_ALL) 4111STEXI 4112@item -dump-vmstate @var{file} 4113@findex -dump-vmstate 4114Dump json-encoded vmstate information for current machine type to file 4115in @var{file} 4116ETEXI 4117 4118STEXI 4119@end table 4120ETEXI 4121DEFHEADING() 4122DEFHEADING(Generic object creation) 4123STEXI 4124@table @option 4125ETEXI 4126 4127DEF("object", HAS_ARG, QEMU_OPTION_object, 4128 "-object TYPENAME[,PROP1=VALUE1,...]\n" 4129 " create a new object of type TYPENAME setting properties\n" 4130 " in the order they are specified. Note that the 'id'\n" 4131 " property must be set. These objects are placed in the\n" 4132 " '/objects' path.\n", 4133 QEMU_ARCH_ALL) 4134STEXI 4135@item -object @var{typename}[,@var{prop1}=@var{value1},...] 4136@findex -object 4137Create a new object of type @var{typename} setting properties 4138in the order they are specified. Note that the 'id' 4139property must be set. These objects are placed in the 4140'/objects' path. 4141 4142@table @option 4143 4144@item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off} 4145 4146Creates a memory file backend object, which can be used to back 4147the guest RAM with huge pages. The @option{id} parameter is a 4148unique ID that will be used to reference this memory region 4149when configuring the @option{-numa} argument. The @option{size} 4150option provides the size of the memory region, and accepts 4151common suffixes, eg @option{500M}. The @option{mem-path} provides 4152the path to either a shared memory or huge page filesystem mount. 4153The @option{share} boolean option determines whether the memory 4154region is marked as private to QEMU, or shared. The latter allows 4155a co-operating external process to access the QEMU memory region. 4156 4157@item -object rng-random,id=@var{id},filename=@var{/dev/random} 4158 4159Creates a random number generator backend which obtains entropy from 4160a device on the host. The @option{id} parameter is a unique ID that 4161will be used to reference this entropy backend from the @option{virtio-rng} 4162device. The @option{filename} parameter specifies which file to obtain 4163entropy from and if omitted defaults to @option{/dev/random}. 4164 4165@item -object rng-egd,id=@var{id},chardev=@var{chardevid} 4166 4167Creates a random number generator backend which obtains entropy from 4168an external daemon running on the host. The @option{id} parameter is 4169a unique ID that will be used to reference this entropy backend from 4170the @option{virtio-rng} device. The @option{chardev} parameter is 4171the unique ID of a character device backend that provides the connection 4172to the RNG daemon. 4173 4174@item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off} 4175 4176Creates a TLS anonymous credentials object, which can be used to provide 4177TLS support on network backends. The @option{id} parameter is a unique 4178ID which network backends will use to access the credentials. The 4179@option{endpoint} is either @option{server} or @option{client} depending 4180on whether the QEMU network backend that uses the credentials will be 4181acting as a client or as a server. If @option{verify-peer} is enabled 4182(the default) then once the handshake is completed, the peer credentials 4183will be verified, though this is a no-op for anonymous credentials. 4184 4185The @var{dir} parameter tells QEMU where to find the credential 4186files. For server endpoints, this directory may contain a file 4187@var{dh-params.pem} providing diffie-hellman parameters to use 4188for the TLS server. If the file is missing, QEMU will generate 4189a set of DH parameters at startup. This is a computationally 4190expensive operation that consumes random pool entropy, so it is 4191recommended that a persistent set of parameters be generated 4192upfront and saved. 4193 4194@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} 4195 4196Creates a TLS anonymous credentials object, which can be used to provide 4197TLS support on network backends. The @option{id} parameter is a unique 4198ID which network backends will use to access the credentials. The 4199@option{endpoint} is either @option{server} or @option{client} depending 4200on whether the QEMU network backend that uses the credentials will be 4201acting as a client or as a server. If @option{verify-peer} is enabled 4202(the default) then once the handshake is completed, the peer credentials 4203will be verified. With x509 certificates, this implies that the clients 4204must be provided with valid client certificates too. 4205 4206The @var{dir} parameter tells QEMU where to find the credential 4207files. For server endpoints, this directory may contain a file 4208@var{dh-params.pem} providing diffie-hellman parameters to use 4209for the TLS server. If the file is missing, QEMU will generate 4210a set of DH parameters at startup. This is a computationally 4211expensive operation that consumes random pool entropy, so it is 4212recommended that a persistent set of parameters be generated 4213upfront and saved. 4214 4215For x509 certificate credentials the directory will contain further files 4216providing the x509 certificates. The certificates must be stored 4217in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional), 4218@var{server-cert.pem} (only servers), @var{server-key.pem} (only servers), 4219@var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients). 4220 4221For the @var{server-key.pem} and @var{client-key.pem} files which 4222contain sensitive private keys, it is possible to use an encrypted 4223version by providing the @var{passwordid} parameter. This provides 4224the ID of a previously created @code{secret} object containing the 4225password for decryption. 4226 4227@item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}] 4228 4229Interval @var{t} can't be 0, this filter batches the packet delivery: all 4230packets arriving in a given interval on netdev @var{netdevid} are delayed 4231until the end of the interval. Interval is in microseconds. 4232@option{status} is optional that indicate whether the netfilter is 4233on (enabled) or off (disabled), the default status for netfilter will be 'on'. 4234 4235queue @var{all|rx|tx} is an option that can be applied to any netfilter. 4236 4237@option{all}: the filter is attached both to the receive and the transmit 4238 queue of the netdev (default). 4239 4240@option{rx}: the filter is attached to the receive queue of the netdev, 4241 where it will receive packets sent to the netdev. 4242 4243@option{tx}: the filter is attached to the transmit queue of the netdev, 4244 where it will receive packets sent by the netdev. 4245 4246@item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid}[,queue=@var{all|rx|tx}] 4247 4248filter-mirror on netdev @var{netdevid},mirror net packet to chardev 4249@var{chardevid} 4250 4251@item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid}, 4252outdev=@var{chardevid}[,queue=@var{all|rx|tx}] 4253 4254filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev 4255@var{chardevid},and redirect indev's packet to filter. 4256Create a filter-redirector we need to differ outdev id from indev id, id can not 4257be the same. we can just use indev or outdev, but at least one of indev or outdev 4258need to be specified. 4259 4260@item -object filter-rewriter,id=@var{id},netdev=@var{netdevid}[,queue=@var{all|rx|tx}] 4261 4262Filter-rewriter is a part of COLO project.It will rewrite tcp packet to 4263secondary from primary to keep secondary tcp connection,and rewrite 4264tcp packet to primary from secondary make tcp packet can be handled by 4265client. 4266 4267usage: 4268colo secondary: 4269-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4270-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4271-object filter-rewriter,id=rew0,netdev=hn0,queue=all 4272 4273@item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}] 4274 4275Dump the network traffic on netdev @var{dev} to the file specified by 4276@var{filename}. At most @var{len} bytes (64k by default) per packet are stored. 4277The file format is libpcap, so it can be analyzed with tools such as tcpdump 4278or Wireshark. 4279 4280@item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid}, 4281outdev=@var{chardevid} 4282 4283Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with 4284secondary packet. If the packets are same, we will output primary 4285packet to outdev@var{chardevid}, else we will notify colo-frame 4286do checkpoint and send primary packet to outdev@var{chardevid}. 4287 4288we must use it with the help of filter-mirror and filter-redirector. 4289 4290@example 4291 4292primary: 4293-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown 4294-device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66 4295-chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait 4296-chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait 4297-chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait 4298-chardev socket,id=compare0-0,host=3.3.3.3,port=9001 4299-chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait 4300-chardev socket,id=compare_out0,host=3.3.3.3,port=9005 4301-object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0 4302-object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out 4303-object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0 4304-object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0 4305 4306secondary: 4307-netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown 4308-device e1000,netdev=hn0,mac=52:a4:00:12:78:66 4309-chardev socket,id=red0,host=3.3.3.3,port=9003 4310-chardev socket,id=red1,host=3.3.3.3,port=9004 4311-object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0 4312-object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1 4313 4314@end example 4315 4316If you want to know the detail of above command line, you can read 4317the colo-compare git log. 4318 4319@item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}] 4320 4321Creates a cryptodev backend which executes crypto opreation from 4322the QEMU cipher APIS. The @var{id} parameter is 4323a unique ID that will be used to reference this cryptodev backend from 4324the @option{virtio-crypto} device. The @var{queues} parameter is optional, 4325which specify the queue number of cryptodev backend, the default of 4326@var{queues} is 1. 4327 4328@example 4329 4330 # qemu-system-x86_64 \ 4331 [...] \ 4332 -object cryptodev-backend-builtin,id=cryptodev0 \ 4333 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \ 4334 [...] 4335@end example 4336 4337@item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4338@item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 4339 4340Defines a secret to store a password, encryption key, or some other sensitive 4341data. The sensitive data can either be passed directly via the @var{data} 4342parameter, or indirectly via the @var{file} parameter. Using the @var{data} 4343parameter is insecure unless the sensitive data is encrypted. 4344 4345The sensitive data can be provided in raw format (the default), or base64. 4346When encoded as JSON, the raw format only supports valid UTF-8 characters, 4347so base64 is recommended for sending binary data. QEMU will convert from 4348which ever format is provided to the format it needs internally. eg, an 4349RBD password can be provided in raw format, even though it will be base64 4350encoded when passed onto the RBD sever. 4351 4352For added protection, it is possible to encrypt the data associated with 4353a secret using the AES-256-CBC cipher. Use of encryption is indicated 4354by providing the @var{keyid} and @var{iv} parameters. The @var{keyid} 4355parameter provides the ID of a previously defined secret that contains 4356the AES-256 decryption key. This key should be 32-bytes long and be 4357base64 encoded. The @var{iv} parameter provides the random initialization 4358vector used for encryption of this particular secret and should be a 4359base64 encrypted string of the 16-byte IV. 4360 4361The simplest (insecure) usage is to provide the secret inline 4362 4363@example 4364 4365 # $QEMU -object secret,id=sec0,data=letmein,format=raw 4366 4367@end example 4368 4369The simplest secure usage is to provide the secret via a file 4370 4371 # echo -n "letmein" > mypasswd.txt 4372 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw 4373 4374For greater security, AES-256-CBC should be used. To illustrate usage, 4375consider the openssl command line tool which can encrypt the data. Note 4376that when encrypting, the plaintext must be padded to the cipher block 4377size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm. 4378 4379First a master key needs to be created in base64 encoding: 4380 4381@example 4382 # openssl rand -base64 32 > key.b64 4383 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"') 4384@end example 4385 4386Each secret to be encrypted needs to have a random initialization vector 4387generated. These do not need to be kept secret 4388 4389@example 4390 # openssl rand -base64 16 > iv.b64 4391 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"') 4392@end example 4393 4394The secret to be defined can now be encrypted, in this case we're 4395telling openssl to base64 encode the result, but it could be left 4396as raw bytes if desired. 4397 4398@example 4399 # SECRET=$(echo -n "letmein" | 4400 openssl enc -aes-256-cbc -a -K $KEY -iv $IV) 4401@end example 4402 4403When launching QEMU, create a master secret pointing to @code{key.b64} 4404and specify that to be used to decrypt the user password. Pass the 4405contents of @code{iv.b64} to the second secret 4406 4407@example 4408 # $QEMU \ 4409 -object secret,id=secmaster0,format=base64,file=key.b64 \ 4410 -object secret,id=sec0,keyid=secmaster0,format=base64,\ 4411 data=$SECRET,iv=$(<iv.b64) 4412@end example 4413 4414@end table 4415 4416ETEXI 4417 4418 4419HXCOMM This is the last statement. Insert new options before this line! 4420STEXI 4421@end table 4422ETEXI 4423
