1HXCOMM Use DEFHEADING() to define headings in both help text and texi 2HXCOMM Text between STEXI and ETEXI are copied to texi version and 3HXCOMM discarded from C version 4HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to 5HXCOMM construct option structures, enums and help message for specified 6HXCOMM architectures. 7HXCOMM HXCOMM can be used for comments, discarded from both texi and C 8 9DEFHEADING(Standard options:) 10STEXI 11@table @option 12ETEXI 13 14DEF("help", 0, QEMU_OPTION_h, 15 "-h or -help display this help and exit\n", QEMU_ARCH_ALL) 16STEXI 17@item -h 18@findex -h 19Display help and exit 20ETEXI 21 22DEF("version", 0, QEMU_OPTION_version, 23 "-version display version information and exit\n", QEMU_ARCH_ALL) 24STEXI 25@item -version 26@findex -version 27Display version information and exit 28ETEXI 29 30DEF("machine", HAS_ARG, QEMU_OPTION_machine, \ 31 "-machine [type=]name[,prop[=value][,...]]\n" 32 " selects emulated machine ('-machine help' for list)\n" 33 " property accel=accel1[:accel2[:...]] selects accelerator\n" 34 " supported accelerators are kvm, xen, tcg (default: tcg)\n" 35 " kernel_irqchip=on|off controls accelerated irqchip support\n" 36 " kernel_irqchip=on|off|split controls accelerated irqchip support (default=off)\n" 37 " vmport=on|off|auto controls emulation of vmport (default: auto)\n" 38 " kvm_shadow_mem=size of KVM shadow MMU\n" 39 " dump-guest-core=on|off include guest memory in a core dump (default=on)\n" 40 " mem-merge=on|off controls memory merge support (default: on)\n" 41 " iommu=on|off controls emulated Intel IOMMU (VT-d) support (default=off)\n" 42 " igd-passthru=on|off controls IGD GFX passthrough support (default=off)\n" 43 " aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n" 44 " dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n" 45 " suppress-vmdesc=on|off disables self-describing migration (default=off)\n" 46 " nvdimm=on|off controls NVDIMM support (default=off)\n" 47 " enforce-config-section=on|off enforce configuration section migration (default=off)\n", 48 QEMU_ARCH_ALL) 49STEXI 50@item -machine [type=]@var{name}[,prop=@var{value}[,...]] 51@findex -machine 52Select the emulated machine by @var{name}. Use @code{-machine help} to list 53available machines. Supported machine properties are: 54@table @option 55@item accel=@var{accels1}[:@var{accels2}[:...]] 56This is used to enable an accelerator. Depending on the target architecture, 57kvm, xen, or tcg can be available. By default, tcg is used. If there is more 58than one accelerator specified, the next one is used if the previous one fails 59to initialize. 60@item kernel_irqchip=on|off 61Controls in-kernel irqchip support for the chosen accelerator when available. 62@item gfx_passthru=on|off 63Enables IGD GFX passthrough support for the chosen machine when available. 64@item vmport=on|off|auto 65Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the 66value based on accel. For accel=xen the default is off otherwise the default 67is on. 68@item kvm_shadow_mem=size 69Defines the size of the KVM shadow MMU. 70@item dump-guest-core=on|off 71Include guest memory in a core dump. The default is on. 72@item mem-merge=on|off 73Enables or disables memory merge support. This feature, when supported by 74the host, de-duplicates identical memory pages among VMs instances 75(enabled by default). 76@item iommu=on|off 77Enables or disables emulated Intel IOMMU (VT-d) support. The default is off. 78@item aes-key-wrap=on|off 79Enables or disables AES key wrapping support on s390-ccw hosts. This feature 80controls whether AES wrapping keys will be created to allow 81execution of AES cryptographic functions. The default is on. 82@item dea-key-wrap=on|off 83Enables or disables DEA key wrapping support on s390-ccw hosts. This feature 84controls whether DEA wrapping keys will be created to allow 85execution of DEA cryptographic functions. The default is on. 86@item nvdimm=on|off 87Enables or disables NVDIMM support. The 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("smp", HAS_ARG, QEMU_OPTION_smp, 103 "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n" 104 " set the number of CPUs to 'n' [default=1]\n" 105 " maxcpus= maximum number of total cpus, including\n" 106 " offline CPUs for hotplug, etc\n" 107 " cores= number of CPU cores on one socket\n" 108 " threads= number of threads on one CPU core\n" 109 " sockets= number of discrete sockets in the system\n", 110 QEMU_ARCH_ALL) 111STEXI 112@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}] 113@findex -smp 114Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255 115CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs 116to 4. 117For the PC target, the number of @var{cores} per socket, the number 118of @var{threads} per cores and the total number of @var{sockets} can be 119specified. Missing values will be computed. If any on the three values is 120given, the total number of CPUs @var{n} can be omitted. @var{maxcpus} 121specifies the maximum number of hotpluggable CPUs. 122ETEXI 123 124DEF("numa", HAS_ARG, QEMU_OPTION_numa, 125 "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n" 126 "-numa node[,memdev=id][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL) 127STEXI 128@item -numa node[,mem=@var{size}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}] 129@itemx -numa node[,memdev=@var{id}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}] 130@findex -numa 131Simulate a multi node NUMA system. If @samp{mem}, @samp{memdev} 132and @samp{cpus} are omitted, resources are split equally. Also, note 133that the -@option{numa} option doesn't allocate any of the specified 134resources. That is, it just assigns existing resources to NUMA nodes. This 135means that one still has to use the @option{-m}, @option{-smp} options 136to allocate RAM and VCPUs respectively, and possibly @option{-object} 137to specify the memory backend for the @samp{memdev} suboption. 138 139@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, if one 140node uses @samp{memdev}, all of them have to use it. 141ETEXI 142 143DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd, 144 "-add-fd fd=fd,set=set[,opaque=opaque]\n" 145 " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL) 146STEXI 147@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}] 148@findex -add-fd 149 150Add a file descriptor to an fd set. Valid options are: 151 152@table @option 153@item fd=@var{fd} 154This option defines the file descriptor of which a duplicate is added to fd set. 155The file descriptor cannot be stdin, stdout, or stderr. 156@item set=@var{set} 157This option defines the ID of the fd set to add the file descriptor to. 158@item opaque=@var{opaque} 159This option defines a free-form string that can be used to describe @var{fd}. 160@end table 161 162You can open an image using pre-opened file descriptors from an fd set: 163@example 164qemu-system-i386 165-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 166-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 167-drive file=/dev/fdset/2,index=0,media=disk 168@end example 169ETEXI 170 171DEF("set", HAS_ARG, QEMU_OPTION_set, 172 "-set group.id.arg=value\n" 173 " set <arg> parameter for item <id> of type <group>\n" 174 " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL) 175STEXI 176@item -set @var{group}.@var{id}.@var{arg}=@var{value} 177@findex -set 178Set parameter @var{arg} for item @var{id} of type @var{group}\n" 179ETEXI 180 181DEF("global", HAS_ARG, QEMU_OPTION_global, 182 "-global driver.property=value\n" 183 "-global driver=driver,property=property,value=value\n" 184 " set a global default for a driver property\n", 185 QEMU_ARCH_ALL) 186STEXI 187@item -global @var{driver}.@var{prop}=@var{value} 188@itemx -global driver=@var{driver},property=@var{property},value=@var{value} 189@findex -global 190Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.: 191 192@example 193qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk 194@end example 195 196In particular, you can use this to set driver properties for devices which are 197created automatically by the machine model. To create a device which is not 198created automatically and set properties on it, use -@option{device}. 199 200-global @var{driver}.@var{prop}=@var{value} is shorthand for -global 201driver=@var{driver},property=@var{prop},value=@var{value}. The 202longhand syntax works even when @var{driver} contains a dot. 203ETEXI 204 205DEF("boot", HAS_ARG, QEMU_OPTION_boot, 206 "-boot [order=drives][,once=drives][,menu=on|off]\n" 207 " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n" 208 " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n" 209 " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n" 210 " 'sp_time': the period that splash picture last if menu=on, unit is ms\n" 211 " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n", 212 QEMU_ARCH_ALL) 213STEXI 214@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] 215@findex -boot 216Specify boot order @var{drives} as a string of drive letters. Valid 217drive letters depend on the target architecture. The x86 PC uses: a, b 218(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot 219from network adapter 1-4), hard disk boot is the default. To apply a 220particular boot order only on the first startup, specify it via 221@option{once}. 222 223Interactive boot menus/prompts can be enabled via @option{menu=on} as far 224as firmware/BIOS supports them. The default is non-interactive boot. 225 226A splash picture could be passed to bios, enabling user to show it as logo, 227when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS 228supports them. Currently Seabios for X86 system support it. 229limitation: The splash file could be a jpeg file or a BMP file in 24 BPP 230format(true color). The resolution should be supported by the SVGA mode, so 231the recommended is 320x240, 640x480, 800x640. 232 233A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms 234when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not 235reboot, qemu passes '-1' to bios by default. Currently Seabios for X86 236system support it. 237 238Do strict boot via @option{strict=on} as far as firmware/BIOS 239supports it. This only effects when boot priority is changed by 240bootindex options. The default is non-strict boot. 241 242@example 243# try to boot from network first, then from hard disk 244qemu-system-i386 -boot order=nc 245# boot from CD-ROM first, switch back to default order after reboot 246qemu-system-i386 -boot once=d 247# boot with a splash picture for 5 seconds. 248qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000 249@end example 250 251Note: The legacy format '-boot @var{drives}' is still supported but its 252use is discouraged as it may be removed from future versions. 253ETEXI 254 255DEF("m", HAS_ARG, QEMU_OPTION_m, 256 "-m[emory] [size=]megs[,slots=n,maxmem=size]\n" 257 " configure guest RAM\n" 258 " size: initial amount of guest memory\n" 259 " slots: number of hotplug slots (default: none)\n" 260 " maxmem: maximum amount of guest memory (default: none)\n" 261 "NOTE: Some architectures might enforce a specific granularity\n", 262 QEMU_ARCH_ALL) 263STEXI 264@item -m [size=]@var{megs}[,slots=n,maxmem=size] 265@findex -m 266Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB. 267Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in 268megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem} 269could be used to set amount of hotpluggable memory slots and maximum amount of 270memory. Note that @var{maxmem} must be aligned to the page size. 271 272For example, the following command-line sets the guest startup RAM size to 2731GB, creates 3 slots to hotplug additional memory and sets the maximum 274memory the guest can reach to 4GB: 275 276@example 277qemu-system-x86_64 -m 1G,slots=3,maxmem=4G 278@end example 279 280If @var{slots} and @var{maxmem} are not specified, memory hotplug won't 281be enabled and the guest startup RAM will never increase. 282ETEXI 283 284DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath, 285 "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL) 286STEXI 287@item -mem-path @var{path} 288@findex -mem-path 289Allocate guest RAM from a temporarily created file in @var{path}. 290ETEXI 291 292DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc, 293 "-mem-prealloc preallocate guest memory (use with -mem-path)\n", 294 QEMU_ARCH_ALL) 295STEXI 296@item -mem-prealloc 297@findex -mem-prealloc 298Preallocate memory when using -mem-path. 299ETEXI 300 301DEF("k", HAS_ARG, QEMU_OPTION_k, 302 "-k language use keyboard layout (for example 'fr' for French)\n", 303 QEMU_ARCH_ALL) 304STEXI 305@item -k @var{language} 306@findex -k 307Use keyboard layout @var{language} (for example @code{fr} for 308French). This option is only needed where it is not easy to get raw PC 309keycodes (e.g. on Macs, with some X11 servers or with a VNC 310display). You don't normally need to use it on PC/Linux or PC/Windows 311hosts. 312 313The available layouts are: 314@example 315ar de-ch es fo fr-ca hu ja mk no pt-br sv 316da en-gb et fr fr-ch is lt nl pl ru th 317de en-us fi fr-be hr it lv nl-be pt sl tr 318@end example 319 320The default is @code{en-us}. 321ETEXI 322 323 324DEF("audio-help", 0, QEMU_OPTION_audio_help, 325 "-audio-help print list of audio drivers and their options\n", 326 QEMU_ARCH_ALL) 327STEXI 328@item -audio-help 329@findex -audio-help 330Will show the audio subsystem help: list of drivers, tunable 331parameters. 332ETEXI 333 334DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw, 335 "-soundhw c1,... enable audio support\n" 336 " and only specified sound cards (comma separated list)\n" 337 " use '-soundhw help' to get the list of supported cards\n" 338 " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL) 339STEXI 340@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all 341@findex -soundhw 342Enable audio and selected sound hardware. Use 'help' to print all 343available sound hardware. 344 345@example 346qemu-system-i386 -soundhw sb16,adlib disk.img 347qemu-system-i386 -soundhw es1370 disk.img 348qemu-system-i386 -soundhw ac97 disk.img 349qemu-system-i386 -soundhw hda disk.img 350qemu-system-i386 -soundhw all disk.img 351qemu-system-i386 -soundhw help 352@end example 353 354Note that Linux's i810_audio OSS kernel (for AC97) module might 355require manually specifying clocking. 356 357@example 358modprobe i810_audio clocking=48000 359@end example 360ETEXI 361 362DEF("balloon", HAS_ARG, QEMU_OPTION_balloon, 363 "-balloon none disable balloon device\n" 364 "-balloon virtio[,addr=str]\n" 365 " enable virtio balloon device (default)\n", QEMU_ARCH_ALL) 366STEXI 367@item -balloon none 368@findex -balloon 369Disable balloon device. 370@item -balloon virtio[,addr=@var{addr}] 371Enable virtio balloon device (default), optionally with PCI address 372@var{addr}. 373ETEXI 374 375DEF("device", HAS_ARG, QEMU_OPTION_device, 376 "-device driver[,prop[=value][,...]]\n" 377 " add device (based on driver)\n" 378 " prop=value,... sets driver properties\n" 379 " use '-device help' to print all possible drivers\n" 380 " use '-device driver,help' to print all possible properties\n", 381 QEMU_ARCH_ALL) 382STEXI 383@item -device @var{driver}[,@var{prop}[=@var{value}][,...]] 384@findex -device 385Add device @var{driver}. @var{prop}=@var{value} sets driver 386properties. Valid properties depend on the driver. To get help on 387possible drivers and properties, use @code{-device help} and 388@code{-device @var{driver},help}. 389 390Some drivers are: 391@item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}] 392 393Add an IPMI BMC. This is a simulation of a hardware management 394interface processor that normally sits on a system. It provides 395a watchdog and the ability to reset and power control the system. 396You need to connect this to an IPMI interface to make it useful 397 398The IPMI slave address to use for the BMC. The default is 0x20. 399This address is the BMC's address on the I2C network of management 400controllers. If you don't know what this means, it is safe to ignore 401it. 402 403@item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}] 404 405Add a connection to an external IPMI BMC simulator. Instead of 406locally emulating the BMC like the above item, instead connect 407to an external entity that provides the IPMI services. 408 409A connection is made to an external BMC simulator. If you do this, it 410is strongly recommended that you use the "reconnect=" chardev option 411to reconnect to the simulator if the connection is lost. Note that if 412this is not used carefully, it can be a security issue, as the 413interface has the ability to send resets, NMIs, and power off the VM. 414It's best if QEMU makes a connection to an external simulator running 415on a secure port on localhost, so neither the simulator nor QEMU is 416exposed to any outside network. 417 418See the "lanserv/README.vm" file in the OpenIPMI library for more 419details on the external interface. 420 421@item -device isa-ipmi-kcs,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 422 423Add a KCS IPMI interafce on the ISA bus. This also adds a 424corresponding ACPI and SMBIOS entries, if appropriate. 425 426@table @option 427@item bmc=@var{id} 428The BMC to connect to, one of ipmi-bmc-sim or ipmi-bmc-extern above. 429@item ioport=@var{val} 430Define the I/O address of the interface. The default is 0xca0 for KCS. 431@item irq=@var{val} 432Define the interrupt to use. The default is 5. To disable interrupts, 433set this to 0. 434@end table 435 436@item -device isa-ipmi-bt,bmc=@var{id}[,ioport=@var{val}][,irq=@var{val}] 437 438Like the KCS interface, but defines a BT interface. The default port is 4390xe4 and the default interrupt is 5. 440 441ETEXI 442 443DEF("name", HAS_ARG, QEMU_OPTION_name, 444 "-name string1[,process=string2][,debug-threads=on|off]\n" 445 " set the name of the guest\n" 446 " string1 sets the window title and string2 the process name (on Linux)\n" 447 " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n" 448 " NOTE: The thread names are for debugging and not a stable API.\n", 449 QEMU_ARCH_ALL) 450STEXI 451@item -name @var{name} 452@findex -name 453Sets the @var{name} of the guest. 454This name will be displayed in the SDL window caption. 455The @var{name} will also be used for the VNC server. 456Also optionally set the top visible process name in Linux. 457Naming of individual threads can also be enabled on Linux to aid debugging. 458ETEXI 459 460DEF("uuid", HAS_ARG, QEMU_OPTION_uuid, 461 "-uuid %08x-%04x-%04x-%04x-%012x\n" 462 " specify machine UUID\n", QEMU_ARCH_ALL) 463STEXI 464@item -uuid @var{uuid} 465@findex -uuid 466Set system UUID. 467ETEXI 468 469STEXI 470@end table 471ETEXI 472DEFHEADING() 473 474DEFHEADING(Block device options:) 475STEXI 476@table @option 477ETEXI 478 479DEF("fda", HAS_ARG, QEMU_OPTION_fda, 480 "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL) 481DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL) 482STEXI 483@item -fda @var{file} 484@itemx -fdb @var{file} 485@findex -fda 486@findex -fdb 487Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). 488ETEXI 489 490DEF("hda", HAS_ARG, QEMU_OPTION_hda, 491 "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL) 492DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL) 493DEF("hdc", HAS_ARG, QEMU_OPTION_hdc, 494 "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL) 495DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL) 496STEXI 497@item -hda @var{file} 498@itemx -hdb @var{file} 499@itemx -hdc @var{file} 500@itemx -hdd @var{file} 501@findex -hda 502@findex -hdb 503@findex -hdc 504@findex -hdd 505Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}). 506ETEXI 507 508DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom, 509 "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n", 510 QEMU_ARCH_ALL) 511STEXI 512@item -cdrom @var{file} 513@findex -cdrom 514Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and 515@option{-cdrom} at the same time). You can use the host CD-ROM by 516using @file{/dev/cdrom} as filename (@pxref{host_drives}). 517ETEXI 518 519DEF("drive", HAS_ARG, QEMU_OPTION_drive, 520 "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" 521 " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n" 522 " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n" 523 " [,serial=s][,addr=A][,rerror=ignore|stop|report]\n" 524 " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n" 525 " [,readonly=on|off][,copy-on-read=on|off]\n" 526 " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n" 527 " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n" 528 " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n" 529 " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n" 530 " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n" 531 " [[,iops_size=is]]\n" 532 " [[,group=g]]\n" 533 " use 'file' as a drive image\n", QEMU_ARCH_ALL) 534STEXI 535@item -drive @var{option}[,@var{option}[,@var{option}[,...]]] 536@findex -drive 537 538Define a new drive. Valid options are: 539 540@table @option 541@item file=@var{file} 542This option defines which disk image (@pxref{disk_images}) to use with 543this drive. If the filename contains comma, you must double it 544(for instance, "file=my,,file" to use file "my,file"). 545 546Special files such as iSCSI devices can be specified using protocol 547specific URLs. See the section for "Device URL Syntax" for more information. 548@item if=@var{interface} 549This option defines on which type on interface the drive is connected. 550Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio. 551@item bus=@var{bus},unit=@var{unit} 552These options define where is connected the drive by defining the bus number and 553the unit id. 554@item index=@var{index} 555This option defines where is connected the drive by using an index in the list 556of available connectors of a given interface type. 557@item media=@var{media} 558This option defines the type of the media: disk or cdrom. 559@item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}] 560These options have the same definition as they have in @option{-hdachs}. 561@item snapshot=@var{snapshot} 562@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive 563(see @option{-snapshot}). 564@item cache=@var{cache} 565@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data. 566@item aio=@var{aio} 567@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO. 568@item discard=@var{discard} 569@var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls whether @dfn{discard} (also known as @dfn{trim} or @dfn{unmap}) requests are ignored or passed to the filesystem. Some machine types may not support discard requests. 570@item format=@var{format} 571Specify which disk @var{format} will be used rather than detecting 572the format. Can be used to specifiy format=raw to avoid interpreting 573an untrusted format header. 574@item serial=@var{serial} 575This option specifies the serial number to assign to the device. 576@item addr=@var{addr} 577Specify the controller's PCI address (if=virtio only). 578@item werror=@var{action},rerror=@var{action} 579Specify which @var{action} to take on write and read errors. Valid actions are: 580"ignore" (ignore the error and try to continue), "stop" (pause QEMU), 581"report" (report the error to the guest), "enospc" (pause QEMU only if the 582host disk is full; report the error to the guest otherwise). 583The default setting is @option{werror=enospc} and @option{rerror=report}. 584@item readonly 585Open drive @option{file} as read-only. Guest write attempts will fail. 586@item copy-on-read=@var{copy-on-read} 587@var{copy-on-read} is "on" or "off" and enables whether to copy read backing 588file sectors into the image file. 589@item detect-zeroes=@var{detect-zeroes} 590@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic 591conversion of plain zero writes by the OS to driver specific optimized 592zero write commands. You may even choose "unmap" if @var{discard} is set 593to "unmap" to allow a zero write to be converted to an UNMAP operation. 594@end table 595 596By default, the @option{cache=writeback} mode is used. It will report data 597writes as completed as soon as the data is present in the host page cache. 598This is safe as long as your guest OS makes sure to correctly flush disk caches 599where needed. If your guest OS does not handle volatile disk write caches 600correctly and your host crashes or loses power, then the guest may experience 601data corruption. 602 603For such guests, you should consider using @option{cache=writethrough}. This 604means that the host page cache will be used to read and write data, but write 605notification will be sent to the guest only after QEMU has made sure to flush 606each write to the disk. Be aware that this has a major impact on performance. 607 608The host page cache can be avoided entirely with @option{cache=none}. This will 609attempt to do disk IO directly to the guest's memory. QEMU may still perform 610an internal copy of the data. Note that this is considered a writeback mode and 611the guest OS must handle the disk write cache correctly in order to avoid data 612corruption on host crashes. 613 614The host page cache can be avoided while only sending write notifications to 615the guest when the data has been flushed to the disk using 616@option{cache=directsync}. 617 618In case you don't care about data integrity over host failures, use 619@option{cache=unsafe}. This option tells QEMU that it never needs to write any 620data to the disk but can instead keep things in cache. If anything goes wrong, 621like your host losing power, the disk storage getting disconnected accidentally, 622etc. your image will most probably be rendered unusable. When using 623the @option{-snapshot} option, unsafe caching is always used. 624 625Copy-on-read avoids accessing the same backing file sectors repeatedly and is 626useful when the backing file is over a slow network. By default copy-on-read 627is off. 628 629Instead of @option{-cdrom} you can use: 630@example 631qemu-system-i386 -drive file=file,index=2,media=cdrom 632@end example 633 634Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can 635use: 636@example 637qemu-system-i386 -drive file=file,index=0,media=disk 638qemu-system-i386 -drive file=file,index=1,media=disk 639qemu-system-i386 -drive file=file,index=2,media=disk 640qemu-system-i386 -drive file=file,index=3,media=disk 641@end example 642 643You can open an image using pre-opened file descriptors from an fd set: 644@example 645qemu-system-i386 646-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" 647-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" 648-drive file=/dev/fdset/2,index=0,media=disk 649@end example 650 651You can connect a CDROM to the slave of ide0: 652@example 653qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom 654@end example 655 656If you don't specify the "file=" argument, you define an empty drive: 657@example 658qemu-system-i386 -drive if=ide,index=1,media=cdrom 659@end example 660 661You can connect a SCSI disk with unit ID 6 on the bus #0: 662@example 663qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6 664@end example 665 666Instead of @option{-fda}, @option{-fdb}, you can use: 667@example 668qemu-system-i386 -drive file=file,index=0,if=floppy 669qemu-system-i386 -drive file=file,index=1,if=floppy 670@end example 671 672By default, @var{interface} is "ide" and @var{index} is automatically 673incremented: 674@example 675qemu-system-i386 -drive file=a -drive file=b" 676@end example 677is interpreted like: 678@example 679qemu-system-i386 -hda a -hdb b 680@end example 681ETEXI 682 683DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock, 684 "-mtdblock file use 'file' as on-board Flash memory image\n", 685 QEMU_ARCH_ALL) 686STEXI 687@item -mtdblock @var{file} 688@findex -mtdblock 689Use @var{file} as on-board Flash memory image. 690ETEXI 691 692DEF("sd", HAS_ARG, QEMU_OPTION_sd, 693 "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL) 694STEXI 695@item -sd @var{file} 696@findex -sd 697Use @var{file} as SecureDigital card image. 698ETEXI 699 700DEF("pflash", HAS_ARG, QEMU_OPTION_pflash, 701 "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL) 702STEXI 703@item -pflash @var{file} 704@findex -pflash 705Use @var{file} as a parallel flash image. 706ETEXI 707 708DEF("snapshot", 0, QEMU_OPTION_snapshot, 709 "-snapshot write to temporary files instead of disk image files\n", 710 QEMU_ARCH_ALL) 711STEXI 712@item -snapshot 713@findex -snapshot 714Write to temporary files instead of disk image files. In this case, 715the raw disk image you use is not written back. You can however force 716the write back by pressing @key{C-a s} (@pxref{disk_images}). 717ETEXI 718 719DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \ 720 "-hdachs c,h,s[,t]\n" \ 721 " force hard disk 0 physical geometry and the optional BIOS\n" \ 722 " translation (t=none or lba) (usually QEMU can guess them)\n", 723 QEMU_ARCH_ALL) 724STEXI 725@item -hdachs @var{c},@var{h},@var{s},[,@var{t}] 726@findex -hdachs 727Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <= 728@var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS 729translation mode (@var{t}=none, lba or auto). Usually QEMU can guess 730all those parameters. This option is useful for old MS-DOS disk 731images. 732ETEXI 733 734DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev, 735 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n" 736 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n", 737 QEMU_ARCH_ALL) 738 739STEXI 740 741@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}] 742@findex -fsdev 743Define a new file system device. Valid options are: 744@table @option 745@item @var{fsdriver} 746This option specifies the fs driver backend to use. 747Currently "local", "handle" and "proxy" file system drivers are supported. 748@item id=@var{id} 749Specifies identifier for this device 750@item path=@var{path} 751Specifies the export path for the file system device. Files under 752this path will be available to the 9p client on the guest. 753@item security_model=@var{security_model} 754Specifies the security model to be used for this export path. 755Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 756In "passthrough" security model, files are stored using the same 757credentials as they are created on the guest. This requires QEMU 758to run as root. In "mapped-xattr" security model, some of the file 759attributes like uid, gid, mode bits and link target are stored as 760file attributes. For "mapped-file" these attributes are stored in the 761hidden .virtfs_metadata directory. Directories exported by this security model cannot 762interact with other unix tools. "none" security model is same as 763passthrough except the sever won't report failures if it fails to 764set file attributes like ownership. Security model is mandatory 765only for local fsdriver. Other fsdrivers (like handle, proxy) don't take 766security model as a parameter. 767@item writeout=@var{writeout} 768This is an optional argument. The only supported value is "immediate". 769This means that host page cache will be used to read and write data but 770write notification will be sent to the guest only when the data has been 771reported as written by the storage subsystem. 772@item readonly 773Enables exporting 9p share as a readonly mount for guests. By default 774read-write access is given. 775@item socket=@var{socket} 776Enables proxy filesystem driver to use passed socket file for communicating 777with virtfs-proxy-helper 778@item sock_fd=@var{sock_fd} 779Enables proxy filesystem driver to use passed socket descriptor for 780communicating with virtfs-proxy-helper. Usually a helper like libvirt 781will create socketpair and pass one of the fds as sock_fd 782@end table 783 784-fsdev option is used along with -device driver "virtio-9p-pci". 785@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag} 786Options for virtio-9p-pci driver are: 787@table @option 788@item fsdev=@var{id} 789Specifies the id value specified along with -fsdev option 790@item mount_tag=@var{mount_tag} 791Specifies the tag name to be used by the guest to mount this export point 792@end table 793 794ETEXI 795 796DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs, 797 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n" 798 " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n", 799 QEMU_ARCH_ALL) 800 801STEXI 802 803@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}] 804@findex -virtfs 805 806The general form of a Virtual File system pass-through options are: 807@table @option 808@item @var{fsdriver} 809This option specifies the fs driver backend to use. 810Currently "local", "handle" and "proxy" file system drivers are supported. 811@item id=@var{id} 812Specifies identifier for this device 813@item path=@var{path} 814Specifies the export path for the file system device. Files under 815this path will be available to the 9p client on the guest. 816@item security_model=@var{security_model} 817Specifies the security model to be used for this export path. 818Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". 819In "passthrough" security model, files are stored using the same 820credentials as they are created on the guest. This requires QEMU 821to run as root. In "mapped-xattr" security model, some of the file 822attributes like uid, gid, mode bits and link target are stored as 823file attributes. For "mapped-file" these attributes are stored in the 824hidden .virtfs_metadata directory. Directories exported by this security model cannot 825interact with other unix tools. "none" security model is same as 826passthrough except the sever won't report failures if it fails to 827set file attributes like ownership. Security model is mandatory only 828for local fsdriver. Other fsdrivers (like handle, proxy) don't take security 829model as a parameter. 830@item writeout=@var{writeout} 831This is an optional argument. The only supported value is "immediate". 832This means that host page cache will be used to read and write data but 833write notification will be sent to the guest only when the data has been 834reported as written by the storage subsystem. 835@item readonly 836Enables exporting 9p share as a readonly mount for guests. By default 837read-write access is given. 838@item socket=@var{socket} 839Enables proxy filesystem driver to use passed socket file for 840communicating with virtfs-proxy-helper. Usually a helper like libvirt 841will create socketpair and pass one of the fds as sock_fd 842@item sock_fd 843Enables proxy filesystem driver to use passed 'sock_fd' as the socket 844descriptor for interfacing with virtfs-proxy-helper 845@end table 846ETEXI 847 848DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth, 849 "-virtfs_synth Create synthetic file system image\n", 850 QEMU_ARCH_ALL) 851STEXI 852@item -virtfs_synth 853@findex -virtfs_synth 854Create synthetic file system image 855ETEXI 856 857STEXI 858@end table 859ETEXI 860DEFHEADING() 861 862DEFHEADING(USB options:) 863STEXI 864@table @option 865ETEXI 866 867DEF("usb", 0, QEMU_OPTION_usb, 868 "-usb enable the USB driver (will be the default soon)\n", 869 QEMU_ARCH_ALL) 870STEXI 871@item -usb 872@findex -usb 873Enable the USB driver (will be the default soon) 874ETEXI 875 876DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice, 877 "-usbdevice name add the host or guest USB device 'name'\n", 878 QEMU_ARCH_ALL) 879STEXI 880 881@item -usbdevice @var{devname} 882@findex -usbdevice 883Add the USB device @var{devname}. @xref{usb_devices}. 884 885@table @option 886 887@item mouse 888Virtual Mouse. This will override the PS/2 mouse emulation when activated. 889 890@item tablet 891Pointer device that uses absolute coordinates (like a touchscreen). This 892means QEMU is able to report the mouse position without having to grab the 893mouse. Also overrides the PS/2 mouse emulation when activated. 894 895@item disk:[format=@var{format}]:@var{file} 896Mass storage device based on file. The optional @var{format} argument 897will be used rather than detecting the format. Can be used to specifiy 898@code{format=raw} to avoid interpreting an untrusted format header. 899 900@item host:@var{bus}.@var{addr} 901Pass through the host device identified by @var{bus}.@var{addr} (Linux only). 902 903@item host:@var{vendor_id}:@var{product_id} 904Pass through the host device identified by @var{vendor_id}:@var{product_id} 905(Linux only). 906 907@item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev} 908Serial converter to host character device @var{dev}, see @code{-serial} for the 909available devices. 910 911@item braille 912Braille device. This will use BrlAPI to display the braille output on a real 913or fake device. 914 915@item net:@var{options} 916Network adapter that supports CDC ethernet and RNDIS protocols. 917 918@end table 919ETEXI 920 921STEXI 922@end table 923ETEXI 924DEFHEADING() 925 926DEFHEADING(Display options:) 927STEXI 928@table @option 929ETEXI 930 931DEF("display", HAS_ARG, QEMU_OPTION_display, 932 "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n" 933 " [,window_close=on|off]|curses|none|\n" 934 " gtk[,grab_on_hover=on|off]|\n" 935 " vnc=<display>[,<optargs>]\n" 936 " select display type\n", QEMU_ARCH_ALL) 937STEXI 938@item -display @var{type} 939@findex -display 940Select type of display to use. This option is a replacement for the 941old style -sdl/-curses/... options. Valid values for @var{type} are 942@table @option 943@item sdl 944Display video output via SDL (usually in a separate graphics 945window; see the SDL documentation for other possibilities). 946@item curses 947Display video output via curses. For graphics device models which 948support a text mode, QEMU can display this output using a 949curses/ncurses interface. Nothing is displayed when the graphics 950device is in graphical mode or if the graphics device does not support 951a text mode. Generally only the VGA device models support text mode. 952@item none 953Do not display video output. The guest will still see an emulated 954graphics card, but its output will not be displayed to the QEMU 955user. This option differs from the -nographic option in that it 956only affects what is done with video output; -nographic also changes 957the destination of the serial and parallel port data. 958@item gtk 959Display video output in a GTK window. This interface provides drop-down 960menus and other UI elements to configure and control the VM during 961runtime. 962@item vnc 963Start a VNC server on display <arg> 964@end table 965ETEXI 966 967DEF("nographic", 0, QEMU_OPTION_nographic, 968 "-nographic disable graphical output and redirect serial I/Os to console\n", 969 QEMU_ARCH_ALL) 970STEXI 971@item -nographic 972@findex -nographic 973Normally, QEMU uses SDL to display the VGA output. With this option, 974you can totally disable graphical output so that QEMU is a simple 975command line application. The emulated serial port is redirected on 976the console and muxed with the monitor (unless redirected elsewhere 977explicitly). Therefore, you can still use QEMU to debug a Linux kernel 978with a serial console. Use @key{C-a h} for help on switching between 979the console and monitor. 980ETEXI 981 982DEF("curses", 0, QEMU_OPTION_curses, 983 "-curses use a curses/ncurses interface instead of SDL\n", 984 QEMU_ARCH_ALL) 985STEXI 986@item -curses 987@findex -curses 988Normally, QEMU uses SDL to display the VGA output. With this option, 989QEMU can display the VGA output when in text mode using a 990curses/ncurses interface. Nothing is displayed in graphical mode. 991ETEXI 992 993DEF("no-frame", 0, QEMU_OPTION_no_frame, 994 "-no-frame open SDL window without a frame and window decorations\n", 995 QEMU_ARCH_ALL) 996STEXI 997@item -no-frame 998@findex -no-frame 999Do not use decorations for SDL windows and start them using the whole 1000available screen space. This makes the using QEMU in a dedicated desktop 1001workspace more convenient. 1002ETEXI 1003 1004DEF("alt-grab", 0, QEMU_OPTION_alt_grab, 1005 "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n", 1006 QEMU_ARCH_ALL) 1007STEXI 1008@item -alt-grab 1009@findex -alt-grab 1010Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also 1011affects the special keys (for fullscreen, monitor-mode switching, etc). 1012ETEXI 1013 1014DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab, 1015 "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n", 1016 QEMU_ARCH_ALL) 1017STEXI 1018@item -ctrl-grab 1019@findex -ctrl-grab 1020Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also 1021affects the special keys (for fullscreen, monitor-mode switching, etc). 1022ETEXI 1023 1024DEF("no-quit", 0, QEMU_OPTION_no_quit, 1025 "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL) 1026STEXI 1027@item -no-quit 1028@findex -no-quit 1029Disable SDL window close capability. 1030ETEXI 1031 1032DEF("sdl", 0, QEMU_OPTION_sdl, 1033 "-sdl enable SDL\n", QEMU_ARCH_ALL) 1034STEXI 1035@item -sdl 1036@findex -sdl 1037Enable SDL. 1038ETEXI 1039 1040DEF("spice", HAS_ARG, QEMU_OPTION_spice, 1041 "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n" 1042 " [,x509-key-file=<file>][,x509-key-password=<file>]\n" 1043 " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n" 1044 " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n" 1045 " [,tls-ciphers=<list>]\n" 1046 " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n" 1047 " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n" 1048 " [,sasl][,password=<secret>][,disable-ticketing]\n" 1049 " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n" 1050 " [,jpeg-wan-compression=[auto|never|always]]\n" 1051 " [,zlib-glz-wan-compression=[auto|never|always]]\n" 1052 " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n" 1053 " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n" 1054 " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n" 1055 " [,gl=[on|off]]\n" 1056 " enable spice\n" 1057 " at least one of {port, tls-port} is mandatory\n", 1058 QEMU_ARCH_ALL) 1059STEXI 1060@item -spice @var{option}[,@var{option}[,...]] 1061@findex -spice 1062Enable the spice remote desktop protocol. Valid options are 1063 1064@table @option 1065 1066@item port=<nr> 1067Set the TCP port spice is listening on for plaintext channels. 1068 1069@item addr=<addr> 1070Set the IP address spice is listening on. Default is any address. 1071 1072@item ipv4 1073@itemx ipv6 1074@itemx unix 1075Force using the specified IP version. 1076 1077@item password=<secret> 1078Set the password you need to authenticate. 1079 1080@item sasl 1081Require that the client use SASL to authenticate with the spice. 1082The exact choice of authentication method used is controlled from the 1083system / user's SASL configuration file for the 'qemu' service. This 1084is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1085unprivileged user, an environment variable SASL_CONF_PATH can be used 1086to make it search alternate locations for the service config. 1087While some SASL auth methods can also provide data encryption (eg GSSAPI), 1088it is recommended that SASL always be combined with the 'tls' and 1089'x509' settings to enable use of SSL and server certificates. This 1090ensures a data encryption preventing compromise of authentication 1091credentials. 1092 1093@item disable-ticketing 1094Allow client connects without authentication. 1095 1096@item disable-copy-paste 1097Disable copy paste between the client and the guest. 1098 1099@item disable-agent-file-xfer 1100Disable spice-vdagent based file-xfer between the client and the guest. 1101 1102@item tls-port=<nr> 1103Set the TCP port spice is listening on for encrypted channels. 1104 1105@item x509-dir=<dir> 1106Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir 1107 1108@item x509-key-file=<file> 1109@itemx x509-key-password=<file> 1110@itemx x509-cert-file=<file> 1111@itemx x509-cacert-file=<file> 1112@itemx x509-dh-key-file=<file> 1113The x509 file names can also be configured individually. 1114 1115@item tls-ciphers=<list> 1116Specify which ciphers to use. 1117 1118@item tls-channel=[main|display|cursor|inputs|record|playback] 1119@itemx plaintext-channel=[main|display|cursor|inputs|record|playback] 1120Force specific channel to be used with or without TLS encryption. The 1121options can be specified multiple times to configure multiple 1122channels. The special name "default" can be used to set the default 1123mode. For channels which are not explicitly forced into one mode the 1124spice client is allowed to pick tls/plaintext as he pleases. 1125 1126@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off] 1127Configure image compression (lossless). 1128Default is auto_glz. 1129 1130@item jpeg-wan-compression=[auto|never|always] 1131@itemx zlib-glz-wan-compression=[auto|never|always] 1132Configure wan image compression (lossy for slow links). 1133Default is auto. 1134 1135@item streaming-video=[off|all|filter] 1136Configure video stream detection. Default is filter. 1137 1138@item agent-mouse=[on|off] 1139Enable/disable passing mouse events via vdagent. Default is on. 1140 1141@item playback-compression=[on|off] 1142Enable/disable audio stream compression (using celt 0.5.1). Default is on. 1143 1144@item seamless-migration=[on|off] 1145Enable/disable spice seamless migration. Default is off. 1146 1147@item gl=[on|off] 1148Enable/disable OpenGL context. Default is off. 1149 1150@end table 1151ETEXI 1152 1153DEF("portrait", 0, QEMU_OPTION_portrait, 1154 "-portrait rotate graphical output 90 deg left (only PXA LCD)\n", 1155 QEMU_ARCH_ALL) 1156STEXI 1157@item -portrait 1158@findex -portrait 1159Rotate graphical output 90 deg left (only PXA LCD). 1160ETEXI 1161 1162DEF("rotate", HAS_ARG, QEMU_OPTION_rotate, 1163 "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n", 1164 QEMU_ARCH_ALL) 1165STEXI 1166@item -rotate @var{deg} 1167@findex -rotate 1168Rotate graphical output some deg left (only PXA LCD). 1169ETEXI 1170 1171DEF("vga", HAS_ARG, QEMU_OPTION_vga, 1172 "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n" 1173 " select video card type\n", QEMU_ARCH_ALL) 1174STEXI 1175@item -vga @var{type} 1176@findex -vga 1177Select type of VGA card to emulate. Valid values for @var{type} are 1178@table @option 1179@item cirrus 1180Cirrus Logic GD5446 Video card. All Windows versions starting from 1181Windows 95 should recognize and use this graphic card. For optimal 1182performances, use 16 bit color depth in the guest and the host OS. 1183(This one is the default) 1184@item std 1185Standard VGA card with Bochs VBE extensions. If your guest OS 1186supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want 1187to use high resolution modes (>= 1280x1024x16) then you should use 1188this option. 1189@item vmware 1190VMWare SVGA-II compatible adapter. Use it if you have sufficiently 1191recent XFree86/XOrg server or Windows guest with a driver for this 1192card. 1193@item qxl 1194QXL paravirtual graphic card. It is VGA compatible (including VESA 11952.0 VBE support). Works best with qxl guest drivers installed though. 1196Recommended choice when using the spice protocol. 1197@item tcx 1198(sun4m only) Sun TCX framebuffer. This is the default framebuffer for 1199sun4m machines and offers both 8-bit and 24-bit colour depths at a 1200fixed resolution of 1024x768. 1201@item cg3 1202(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer 1203for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP) 1204resolutions aimed at people wishing to run older Solaris versions. 1205@item virtio 1206Virtio VGA card. 1207@item none 1208Disable VGA card. 1209@end table 1210ETEXI 1211 1212DEF("full-screen", 0, QEMU_OPTION_full_screen, 1213 "-full-screen start in full screen\n", QEMU_ARCH_ALL) 1214STEXI 1215@item -full-screen 1216@findex -full-screen 1217Start in full screen. 1218ETEXI 1219 1220DEF("g", 1, QEMU_OPTION_g , 1221 "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n", 1222 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 1223STEXI 1224@item -g @var{width}x@var{height}[x@var{depth}] 1225@findex -g 1226Set the initial graphical resolution and depth (PPC, SPARC only). 1227ETEXI 1228 1229DEF("vnc", HAS_ARG, QEMU_OPTION_vnc , 1230 "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL) 1231STEXI 1232@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]] 1233@findex -vnc 1234Normally, QEMU uses SDL to display the VGA output. With this option, 1235you can have QEMU listen on VNC display @var{display} and redirect the VGA 1236display over the VNC session. It is very useful to enable the usb 1237tablet device when using this option (option @option{-usbdevice 1238tablet}). When using the VNC display, you must use the @option{-k} 1239parameter to set the keyboard layout if you are not using en-us. Valid 1240syntax for the @var{display} is 1241 1242@table @option 1243 1244@item @var{host}:@var{d} 1245 1246TCP connections will only be allowed from @var{host} on display @var{d}. 1247By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can 1248be omitted in which case the server will accept connections from any host. 1249 1250@item unix:@var{path} 1251 1252Connections will be allowed over UNIX domain sockets where @var{path} is the 1253location of a unix socket to listen for connections on. 1254 1255@item none 1256 1257VNC is initialized but not started. The monitor @code{change} command 1258can be used to later start the VNC server. 1259 1260@end table 1261 1262Following the @var{display} value there may be one or more @var{option} flags 1263separated by commas. Valid options are 1264 1265@table @option 1266 1267@item reverse 1268 1269Connect to a listening VNC client via a ``reverse'' connection. The 1270client is specified by the @var{display}. For reverse network 1271connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument 1272is a TCP port number, not a display number. 1273 1274@item websocket 1275 1276Opens an additional TCP listening port dedicated to VNC Websocket connections. 1277By definition the Websocket port is 5700+@var{display}. If @var{host} is 1278specified connections will only be allowed from this host. 1279As an alternative the Websocket port could be specified by using 1280@code{websocket}=@var{port}. 1281If no TLS credentials are provided, the websocket connection runs in 1282unencrypted mode. If TLS credentials are provided, the websocket connection 1283requires encrypted client connections. 1284 1285@item password 1286 1287Require that password based authentication is used for client connections. 1288 1289The password must be set separately using the @code{set_password} command in 1290the @ref{pcsys_monitor}. The syntax to change your password is: 1291@code{set_password <protocol> <password>} where <protocol> could be either 1292"vnc" or "spice". 1293 1294If you would like to change <protocol> password expiration, you should use 1295@code{expire_password <protocol> <expiration-time>} where expiration time could 1296be one of the following options: now, never, +seconds or UNIX time of 1297expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800 1298to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this 1299date and time). 1300 1301You can also use keywords "now" or "never" for the expiration time to 1302allow <protocol> password to expire immediately or never expire. 1303 1304@item tls-creds=@var{ID} 1305 1306Provides the ID of a set of TLS credentials to use to secure the 1307VNC server. They will apply to both the normal VNC server socket 1308and the websocket socket (if enabled). Setting TLS credentials 1309will cause the VNC server socket to enable the VeNCrypt auth 1310mechanism. The credentials should have been previously created 1311using the @option{-object tls-creds} argument. 1312 1313The @option{tls-creds} parameter obsoletes the @option{tls}, 1314@option{x509}, and @option{x509verify} options, and as such 1315it is not permitted to set both new and old type options at 1316the same time. 1317 1318@item tls 1319 1320Require that client use TLS when communicating with the VNC server. This 1321uses anonymous TLS credentials so is susceptible to a man-in-the-middle 1322attack. It is recommended that this option be combined with either the 1323@option{x509} or @option{x509verify} options. 1324 1325This option is now deprecated in favor of using the @option{tls-creds} 1326argument. 1327 1328@item x509=@var{/path/to/certificate/dir} 1329 1330Valid if @option{tls} is specified. Require that x509 credentials are used 1331for negotiating the TLS session. The server will send its x509 certificate 1332to the client. It is recommended that a password be set on the VNC server 1333to provide authentication of the client when this is used. The path following 1334this option specifies where the x509 certificates are to be loaded from. 1335See the @ref{vnc_security} section for details on generating certificates. 1336 1337This option is now deprecated in favour of using the @option{tls-creds} 1338argument. 1339 1340@item x509verify=@var{/path/to/certificate/dir} 1341 1342Valid if @option{tls} is specified. Require that x509 credentials are used 1343for negotiating the TLS session. The server will send its x509 certificate 1344to the client, and request that the client send its own x509 certificate. 1345The server will validate the client's certificate against the CA certificate, 1346and reject clients when validation fails. If the certificate authority is 1347trusted, this is a sufficient authentication mechanism. You may still wish 1348to set a password on the VNC server as a second authentication layer. The 1349path following this option specifies where the x509 certificates are to 1350be loaded from. See the @ref{vnc_security} section for details on generating 1351certificates. 1352 1353This option is now deprecated in favour of using the @option{tls-creds} 1354argument. 1355 1356@item sasl 1357 1358Require that the client use SASL to authenticate with the VNC server. 1359The exact choice of authentication method used is controlled from the 1360system / user's SASL configuration file for the 'qemu' service. This 1361is typically found in /etc/sasl2/qemu.conf. If running QEMU as an 1362unprivileged user, an environment variable SASL_CONF_PATH can be used 1363to make it search alternate locations for the service config. 1364While some SASL auth methods can also provide data encryption (eg GSSAPI), 1365it is recommended that SASL always be combined with the 'tls' and 1366'x509' settings to enable use of SSL and server certificates. This 1367ensures a data encryption preventing compromise of authentication 1368credentials. See the @ref{vnc_security} section for details on using 1369SASL authentication. 1370 1371@item acl 1372 1373Turn on access control lists for checking of the x509 client certificate 1374and SASL party. For x509 certs, the ACL check is made against the 1375certificate's distinguished name. This is something that looks like 1376@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is 1377made against the username, which depending on the SASL plugin, may 1378include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}. 1379When the @option{acl} flag is set, the initial access list will be 1380empty, with a @code{deny} policy. Thus no one will be allowed to 1381use the VNC server until the ACLs have been loaded. This can be 1382achieved using the @code{acl} monitor command. 1383 1384@item lossy 1385 1386Enable lossy compression methods (gradient, JPEG, ...). If this 1387option is set, VNC client may receive lossy framebuffer updates 1388depending on its encoding settings. Enabling this option can save 1389a lot of bandwidth at the expense of quality. 1390 1391@item non-adaptive 1392 1393Disable adaptive encodings. Adaptive encodings are enabled by default. 1394An adaptive encoding will try to detect frequently updated screen regions, 1395and send updates in these regions using a lossy encoding (like JPEG). 1396This can be really helpful to save bandwidth when playing videos. Disabling 1397adaptive encodings restores the original static behavior of encodings 1398like Tight. 1399 1400@item share=[allow-exclusive|force-shared|ignore] 1401 1402Set display sharing policy. 'allow-exclusive' allows clients to ask 1403for exclusive access. As suggested by the rfb spec this is 1404implemented by dropping other connections. Connecting multiple 1405clients in parallel requires all clients asking for a shared session 1406(vncviewer: -shared switch). This is the default. 'force-shared' 1407disables exclusive client access. Useful for shared desktop sessions, 1408where you don't want someone forgetting specify -shared disconnect 1409everybody else. 'ignore' completely ignores the shared flag and 1410allows everybody connect unconditionally. Doesn't conform to the rfb 1411spec but is traditional QEMU behavior. 1412 1413@end table 1414ETEXI 1415 1416STEXI 1417@end table 1418ETEXI 1419ARCHHEADING(, QEMU_ARCH_I386) 1420 1421ARCHHEADING(i386 target only:, QEMU_ARCH_I386) 1422STEXI 1423@table @option 1424ETEXI 1425 1426DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack, 1427 "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n", 1428 QEMU_ARCH_I386) 1429STEXI 1430@item -win2k-hack 1431@findex -win2k-hack 1432Use it when installing Windows 2000 to avoid a disk full bug. After 1433Windows 2000 is installed, you no longer need this option (this option 1434slows down the IDE transfers). 1435ETEXI 1436 1437HXCOMM Deprecated by -rtc 1438DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386) 1439 1440DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk, 1441 "-no-fd-bootchk disable boot signature checking for floppy disks\n", 1442 QEMU_ARCH_I386) 1443STEXI 1444@item -no-fd-bootchk 1445@findex -no-fd-bootchk 1446Disable boot signature checking for floppy disks in BIOS. May 1447be needed to boot from old floppy disks. 1448ETEXI 1449 1450DEF("no-acpi", 0, QEMU_OPTION_no_acpi, 1451 "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1452STEXI 1453@item -no-acpi 1454@findex -no-acpi 1455Disable ACPI (Advanced Configuration and Power Interface) support. Use 1456it if your guest OS complains about ACPI problems (PC target machine 1457only). 1458ETEXI 1459 1460DEF("no-hpet", 0, QEMU_OPTION_no_hpet, 1461 "-no-hpet disable HPET\n", QEMU_ARCH_I386) 1462STEXI 1463@item -no-hpet 1464@findex -no-hpet 1465Disable HPET support. 1466ETEXI 1467 1468DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable, 1469 "-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" 1470 " ACPI table description\n", QEMU_ARCH_I386) 1471STEXI 1472@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}]...] 1473@findex -acpitable 1474Add ACPI table with specified header fields and context from specified files. 1475For file=, take whole ACPI table from the specified files, including all 1476ACPI headers (possible overridden by other options). 1477For data=, only data 1478portion of the table is used, all header information is specified in the 1479command line. 1480If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id 1481fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order 1482to ensure the field matches required by the Microsoft SLIC spec and the ACPI 1483spec. 1484ETEXI 1485 1486DEF("smbios", HAS_ARG, QEMU_OPTION_smbios, 1487 "-smbios file=binary\n" 1488 " load SMBIOS entry from binary file\n" 1489 "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n" 1490 " [,uefi=on|off]\n" 1491 " specify SMBIOS type 0 fields\n" 1492 "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1493 " [,uuid=uuid][,sku=str][,family=str]\n" 1494 " specify SMBIOS type 1 fields\n" 1495 "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n" 1496 " [,asset=str][,location=str]\n" 1497 " specify SMBIOS type 2 fields\n" 1498 "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n" 1499 " [,sku=str]\n" 1500 " specify SMBIOS type 3 fields\n" 1501 "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n" 1502 " [,asset=str][,part=str]\n" 1503 " specify SMBIOS type 4 fields\n" 1504 "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n" 1505 " [,asset=str][,part=str][,speed=%d]\n" 1506 " specify SMBIOS type 17 fields\n", 1507 QEMU_ARCH_I386 | QEMU_ARCH_ARM) 1508STEXI 1509@item -smbios file=@var{binary} 1510@findex -smbios 1511Load SMBIOS entry from binary file. 1512 1513@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off] 1514Specify SMBIOS type 0 fields 1515 1516@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}] 1517Specify SMBIOS type 1 fields 1518 1519@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}] 1520Specify SMBIOS type 2 fields 1521 1522@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}] 1523Specify SMBIOS type 3 fields 1524 1525@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}] 1526Specify SMBIOS type 4 fields 1527 1528@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}] 1529Specify SMBIOS type 17 fields 1530ETEXI 1531 1532STEXI 1533@end table 1534ETEXI 1535DEFHEADING() 1536 1537DEFHEADING(Network options:) 1538STEXI 1539@table @option 1540ETEXI 1541 1542HXCOMM Legacy slirp options (now moved to -net user): 1543#ifdef CONFIG_SLIRP 1544DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL) 1545DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL) 1546DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL) 1547#ifndef _WIN32 1548DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL) 1549#endif 1550#endif 1551 1552DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, 1553#ifdef CONFIG_SLIRP 1554 "-netdev user,id=str[,net=addr[/mask]][,host=addr][,ipv6-net=addr[/int]]\n" 1555 " [,ipv6-host=addr][,restrict=on|off][,hostname=host][,dhcpstart=addr]\n" 1556 " [,dns=addr][,ipv6-dns=addr][,dnssearch=domain][,tftp=dir]\n" 1557 " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]" 1558#ifndef _WIN32 1559 "[,smb=dir[,smbserver=addr]]\n" 1560#endif 1561 " configure a user mode network backend with ID 'str',\n" 1562 " its DHCP server and optional services\n" 1563#endif 1564#ifdef _WIN32 1565 "-netdev tap,id=str,ifname=name\n" 1566 " configure a host TAP network backend with ID 'str'\n" 1567#else 1568 "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n" 1569 " [,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n" 1570 " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n" 1571 " configure a host TAP network backend with ID 'str'\n" 1572 " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n" 1573 " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n" 1574 " to deconfigure it\n" 1575 " use '[down]script=no' to disable script execution\n" 1576 " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n" 1577 " configure it\n" 1578 " use 'fd=h' to connect to an already opened TAP interface\n" 1579 " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n" 1580 " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n" 1581 " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n" 1582 " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n" 1583 " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" 1584 " use vhost=on to enable experimental in kernel accelerator\n" 1585 " (only has effect for virtio guests which use MSIX)\n" 1586 " use vhostforce=on to force vhost on for non-MSIX virtio guests\n" 1587 " use 'vhostfd=h' to connect to an already opened vhost net device\n" 1588 " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n" 1589 " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n" 1590 "-netdev bridge,id=str[,br=bridge][,helper=helper]\n" 1591 " configure a host TAP network backend with ID 'str' that is\n" 1592 " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" 1593 " using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n" 1594#endif 1595#ifdef __linux__ 1596 "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n" 1597 " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n" 1598 " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n" 1599 " [,rxcookie=rxcookie][,offset=offset]\n" 1600 " configure a network backend with ID 'str' connected to\n" 1601 " an Ethernet over L2TPv3 pseudowire.\n" 1602 " Linux kernel 3.3+ as well as most routers can talk\n" 1603 " L2TPv3. This transport allows connecting a VM to a VM,\n" 1604 " VM to a router and even VM to Host. It is a nearly-universal\n" 1605 " standard (RFC3391). Note - this implementation uses static\n" 1606 " pre-configured tunnels (same as the Linux kernel).\n" 1607 " use 'src=' to specify source address\n" 1608 " use 'dst=' to specify destination address\n" 1609 " use 'udp=on' to specify udp encapsulation\n" 1610 " use 'srcport=' to specify source udp port\n" 1611 " use 'dstport=' to specify destination udp port\n" 1612 " use 'ipv6=on' to force v6\n" 1613 " L2TPv3 uses cookies to prevent misconfiguration as\n" 1614 " well as a weak security measure\n" 1615 " use 'rxcookie=0x012345678' to specify a rxcookie\n" 1616 " use 'txcookie=0x012345678' to specify a txcookie\n" 1617 " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n" 1618 " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n" 1619 " use 'pincounter=on' to work around broken counter handling in peer\n" 1620 " use 'offset=X' to add an extra offset between header and data\n" 1621#endif 1622 "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n" 1623 " configure a network backend to connect to another network\n" 1624 " using a socket connection\n" 1625 "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n" 1626 " configure a network backend to connect to a multicast maddr and port\n" 1627 " use 'localaddr=addr' to specify the host address to send packets from\n" 1628 "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n" 1629 " configure a network backend to connect to another network\n" 1630 " using an UDP tunnel\n" 1631#ifdef CONFIG_VDE 1632 "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n" 1633 " configure a network backend to connect to port 'n' of a vde switch\n" 1634 " running on host and listening for incoming connections on 'socketpath'.\n" 1635 " Use group 'groupname' and mode 'octalmode' to change default\n" 1636 " ownership and permissions for communication port.\n" 1637#endif 1638#ifdef CONFIG_NETMAP 1639 "-netdev netmap,id=str,ifname=name[,devname=nmname]\n" 1640 " attach to the existing netmap-enabled network interface 'name', or to a\n" 1641 " VALE port (created on the fly) called 'name' ('nmname' is name of the \n" 1642 " netmap device, defaults to '/dev/netmap')\n" 1643#endif 1644 "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n" 1645 " configure a vhost-user network, backed by a chardev 'dev'\n" 1646 "-netdev hubport,id=str,hubid=n\n" 1647 " configure a hub port on QEMU VLAN 'n'\n", QEMU_ARCH_ALL) 1648DEF("net", HAS_ARG, QEMU_OPTION_net, 1649 "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n" 1650 " old way to create a new NIC and connect it to VLAN 'n'\n" 1651 " (use the '-device devtype,netdev=str' option if possible instead)\n" 1652 "-net dump[,vlan=n][,file=f][,len=n]\n" 1653 " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n" 1654 "-net none use it alone to have zero network devices. If no -net option\n" 1655 " is provided, the default is '-net nic -net user'\n" 1656 "-net [" 1657#ifdef CONFIG_SLIRP 1658 "user|" 1659#endif 1660 "tap|" 1661 "bridge|" 1662#ifdef CONFIG_VDE 1663 "vde|" 1664#endif 1665#ifdef CONFIG_NETMAP 1666 "netmap|" 1667#endif 1668 "socket][,vlan=n][,option][,option][,...]\n" 1669 " old way to initialize a host network interface\n" 1670 " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL) 1671STEXI 1672@item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}] 1673@findex -net 1674Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n} 1675= 0 is the default). The NIC is an e1000 by default on the PC 1676target. Optionally, the MAC address can be changed to @var{mac}, the 1677device address set to @var{addr} (PCI cards only), 1678and a @var{name} can be assigned for use in monitor commands. 1679Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors 1680that the card should have; this option currently only affects virtio cards; set 1681@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single 1682NIC is created. QEMU can emulate several different models of network card. 1683Valid values for @var{type} are 1684@code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er}, 1685@code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139}, 1686@code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}. 1687Not all devices are supported on all targets. Use @code{-net nic,model=help} 1688for a list of available devices for your target. 1689 1690@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...] 1691@findex -netdev 1692@item -net user[,@var{option}][,@var{option}][,...] 1693Use the user mode network stack which requires no administrator 1694privilege to run. Valid options are: 1695 1696@table @option 1697@item vlan=@var{n} 1698Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default). 1699 1700@item id=@var{id} 1701@itemx name=@var{name} 1702Assign symbolic name for use in monitor commands. 1703 1704@item net=@var{addr}[/@var{mask}] 1705Set IP network address the guest will see. Optionally specify the netmask, 1706either in the form a.b.c.d or as number of valid top-most bits. Default is 170710.0.2.0/24. 1708 1709@item host=@var{addr} 1710Specify the guest-visible address of the host. Default is the 2nd IP in the 1711guest network, i.e. x.x.x.2. 1712 1713@item ipv6-net=@var{addr}[/@var{int}] 1714Set IPv6 network address the guest will see (default is fec0::/64). The 1715network prefix is given in the usual hexadecimal IPv6 address 1716notation. The prefix size is optional, and is given as the number of 1717valid top-most bits (default is 64). 1718 1719@item ipv6-host=@var{addr} 1720Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in 1721the guest network, i.e. xxxx::2. 1722 1723@item restrict=on|off 1724If this option is enabled, the guest will be isolated, i.e. it will not be 1725able to contact the host and no guest IP packets will be routed over the host 1726to the outside. This option does not affect any explicitly set forwarding rules. 1727 1728@item hostname=@var{name} 1729Specifies the client hostname reported by the built-in DHCP server. 1730 1731@item dhcpstart=@var{addr} 1732Specify the first of the 16 IPs the built-in DHCP server can assign. Default 1733is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31. 1734 1735@item dns=@var{addr} 1736Specify the guest-visible address of the virtual nameserver. The address must 1737be different from the host address. Default is the 3rd IP in the guest network, 1738i.e. x.x.x.3. 1739 1740@item ipv6-dns=@var{addr} 1741Specify the guest-visible address of the IPv6 virtual nameserver. The address 1742must be different from the host address. Default is the 3rd IP in the guest 1743network, i.e. xxxx::3. 1744 1745@item dnssearch=@var{domain} 1746Provides an entry for the domain-search list sent by the built-in 1747DHCP server. More than one domain suffix can be transmitted by specifying 1748this option multiple times. If supported, this will cause the guest to 1749automatically try to append the given domain suffix(es) in case a domain name 1750can not be resolved. 1751 1752Example: 1753@example 1754qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...] 1755@end example 1756 1757@item tftp=@var{dir} 1758When using the user mode network stack, activate a built-in TFTP 1759server. The files in @var{dir} will be exposed as the root of a TFTP server. 1760The TFTP client on the guest must be configured in binary mode (use the command 1761@code{bin} of the Unix TFTP client). 1762 1763@item bootfile=@var{file} 1764When using the user mode network stack, broadcast @var{file} as the BOOTP 1765filename. In conjunction with @option{tftp}, this can be used to network boot 1766a guest from a local directory. 1767 1768Example (using pxelinux): 1769@example 1770qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0 1771@end example 1772 1773@item smb=@var{dir}[,smbserver=@var{addr}] 1774When using the user mode network stack, activate a built-in SMB 1775server so that Windows OSes can access to the host files in @file{@var{dir}} 1776transparently. The IP address of the SMB server can be set to @var{addr}. By 1777default the 4th IP in the guest network is used, i.e. x.x.x.4. 1778 1779In the guest Windows OS, the line: 1780@example 178110.0.2.4 smbserver 1782@end example 1783must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me) 1784or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000). 1785 1786Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}. 1787 1788Note that a SAMBA server must be installed on the host OS. 1789QEMU was tested successfully with smbd versions from Red Hat 9, 1790Fedora Core 3 and OpenSUSE 11.x. 1791 1792@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport} 1793Redirect incoming TCP or UDP connections to the host port @var{hostport} to 1794the guest IP address @var{guestaddr} on guest port @var{guestport}. If 1795@var{guestaddr} is not specified, its value is x.x.x.15 (default first address 1796given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can 1797be bound to a specific host interface. If no connection type is set, TCP is 1798used. This option can be given multiple times. 1799 1800For example, to redirect host X11 connection from screen 1 to guest 1801screen 0, use the following: 1802 1803@example 1804# on the host 1805qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...] 1806# this host xterm should open in the guest X11 server 1807xterm -display :1 1808@end example 1809 1810To redirect telnet connections from host port 5555 to telnet port on 1811the guest, use the following: 1812 1813@example 1814# on the host 1815qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...] 1816telnet localhost 5555 1817@end example 1818 1819Then when you use on the host @code{telnet localhost 5555}, you 1820connect to the guest telnet server. 1821 1822@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev} 1823@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command} 1824Forward guest TCP connections to the IP address @var{server} on port @var{port} 1825to the character device @var{dev} or to a program executed by @var{cmd:command} 1826which gets spawned for each connection. This option can be given multiple times. 1827 1828You can either use a chardev directly and have that one used throughout QEMU's 1829lifetime, like in the following example: 1830 1831@example 1832# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever 1833# the guest accesses it 1834qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...] 1835@end example 1836 1837Or you can execute a command on every TCP connection established by the guest, 1838so that QEMU behaves similar to an inetd process for that virtual server: 1839 1840@example 1841# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 1842# and connect the TCP stream to its stdin/stdout 1843qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321' 1844@end example 1845 1846@end table 1847 1848Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still 1849processed and applied to -net user. Mixing them with the new configuration 1850syntax gives undefined results. Their use for new applications is discouraged 1851as they will be removed from future versions. 1852 1853@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}] 1854@itemx -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}] 1855Connect the host TAP network interface @var{name} to VLAN @var{n}. 1856 1857Use the network script @var{file} to configure it and the network script 1858@var{dfile} to deconfigure it. If @var{name} is not provided, the OS 1859automatically provides one. The default network configure script is 1860@file{/etc/qemu-ifup} and the default network deconfigure script is 1861@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no} 1862to disable script execution. 1863 1864If running QEMU as an unprivileged user, use the network helper 1865@var{helper} to configure the TAP interface. The default network 1866helper executable is @file{/path/to/qemu-bridge-helper}. 1867 1868@option{fd}=@var{h} can be used to specify the handle of an already 1869opened host TAP interface. 1870 1871Examples: 1872 1873@example 1874#launch a QEMU instance with the default network script 1875qemu-system-i386 linux.img -net nic -net tap 1876@end example 1877 1878@example 1879#launch a QEMU instance with two NICs, each one connected 1880#to a TAP device 1881qemu-system-i386 linux.img \ 1882 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \ 1883 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1 1884@end example 1885 1886@example 1887#launch a QEMU instance with the default network helper to 1888#connect a TAP device to bridge br0 1889qemu-system-i386 linux.img \ 1890 -net nic -net tap,"helper=/path/to/qemu-bridge-helper" 1891@end example 1892 1893@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}] 1894@itemx -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}] 1895Connect a host TAP network interface to a host bridge device. 1896 1897Use the network helper @var{helper} to configure the TAP interface and 1898attach it to the bridge. The default network helper executable is 1899@file{/path/to/qemu-bridge-helper} and the default bridge 1900device is @file{br0}. 1901 1902Examples: 1903 1904@example 1905#launch a QEMU instance with the default network helper to 1906#connect a TAP device to bridge br0 1907qemu-system-i386 linux.img -net bridge -net nic,model=virtio 1908@end example 1909 1910@example 1911#launch a QEMU instance with the default network helper to 1912#connect a TAP device to bridge qemubr0 1913qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio 1914@end example 1915 1916@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 1917@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] 1918 1919Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual 1920machine using a TCP socket connection. If @option{listen} is 1921specified, QEMU waits for incoming connections on @var{port} 1922(@var{host} is optional). @option{connect} is used to connect to 1923another QEMU instance using the @option{listen} option. @option{fd}=@var{h} 1924specifies an already opened TCP socket. 1925 1926Example: 1927@example 1928# launch a first QEMU instance 1929qemu-system-i386 linux.img \ 1930 -net nic,macaddr=52:54:00:12:34:56 \ 1931 -net socket,listen=:1234 1932# connect the VLAN 0 of this instance to the VLAN 0 1933# of the first instance 1934qemu-system-i386 linux.img \ 1935 -net nic,macaddr=52:54:00:12:34:57 \ 1936 -net socket,connect=127.0.0.1:1234 1937@end example 1938 1939@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 1940@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] 1941 1942Create a VLAN @var{n} shared with another QEMU virtual 1943machines using a UDP multicast socket, effectively making a bus for 1944every QEMU with same multicast address @var{maddr} and @var{port}. 1945NOTES: 1946@enumerate 1947@item 1948Several QEMU can be running on different hosts and share same bus (assuming 1949correct multicast setup for these hosts). 1950@item 1951mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see 1952@url{http://user-mode-linux.sf.net}. 1953@item 1954Use @option{fd=h} to specify an already opened UDP multicast socket. 1955@end enumerate 1956 1957Example: 1958@example 1959# launch one QEMU instance 1960qemu-system-i386 linux.img \ 1961 -net nic,macaddr=52:54:00:12:34:56 \ 1962 -net socket,mcast=230.0.0.1:1234 1963# launch another QEMU instance on same "bus" 1964qemu-system-i386 linux.img \ 1965 -net nic,macaddr=52:54:00:12:34:57 \ 1966 -net socket,mcast=230.0.0.1:1234 1967# launch yet another QEMU instance on same "bus" 1968qemu-system-i386 linux.img \ 1969 -net nic,macaddr=52:54:00:12:34:58 \ 1970 -net socket,mcast=230.0.0.1:1234 1971@end example 1972 1973Example (User Mode Linux compat.): 1974@example 1975# launch QEMU instance (note mcast address selected 1976# is UML's default) 1977qemu-system-i386 linux.img \ 1978 -net nic,macaddr=52:54:00:12:34:56 \ 1979 -net socket,mcast=239.192.168.1:1102 1980# launch UML 1981/path/to/linux ubd0=/path/to/root_fs eth0=mcast 1982@end example 1983 1984Example (send packets from host's 1.2.3.4): 1985@example 1986qemu-system-i386 linux.img \ 1987 -net nic,macaddr=52:54:00:12:34:56 \ 1988 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4 1989@end example 1990 1991@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}] 1992@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}] 1993Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular 1994protocol to transport Ethernet (and other Layer 2) data frames between 1995two systems. It is present in routers, firewalls and the Linux kernel 1996(from version 3.3 onwards). 1997 1998This transport allows a VM to communicate to another VM, router or firewall directly. 1999 2000@item src=@var{srcaddr} 2001 source address (mandatory) 2002@item dst=@var{dstaddr} 2003 destination address (mandatory) 2004@item udp 2005 select udp encapsulation (default is ip). 2006@item srcport=@var{srcport} 2007 source udp port. 2008@item dstport=@var{dstport} 2009 destination udp port. 2010@item ipv6 2011 force v6, otherwise defaults to v4. 2012@item rxcookie=@var{rxcookie} 2013@itemx txcookie=@var{txcookie} 2014 Cookies are a weak form of security in the l2tpv3 specification. 2015Their function is mostly to prevent misconfiguration. By default they are 32 2016bit. 2017@item cookie64 2018 Set cookie size to 64 bit instead of the default 32 2019@item counter=off 2020 Force a 'cut-down' L2TPv3 with no counter as in 2021draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00 2022@item pincounter=on 2023 Work around broken counter handling in peer. This may also help on 2024networks which have packet reorder. 2025@item offset=@var{offset} 2026 Add an extra offset between header and data 2027 2028For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan 2029on the remote Linux host 1.2.3.4: 2030@example 2031# Setup tunnel on linux host using raw ip as encapsulation 2032# on 1.2.3.4 2033ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \ 2034 encap udp udp_sport 16384 udp_dport 16384 2035ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \ 2036 0xFFFFFFFF peer_session_id 0xFFFFFFFF 2037ifconfig vmtunnel0 mtu 1500 2038ifconfig vmtunnel0 up 2039brctl addif br-lan vmtunnel0 2040 2041 2042# on 4.3.2.1 2043# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter 2044 2045qemu-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 2046 2047 2048@end example 2049 2050@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 2051@itemx -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] 2052Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and 2053listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname} 2054and MODE @var{octalmode} to change default ownership and permissions for 2055communication port. This option is only available if QEMU has been compiled 2056with vde support enabled. 2057 2058Example: 2059@example 2060# launch vde switch 2061vde_switch -F -sock /tmp/myswitch 2062# launch QEMU instance 2063qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch 2064@end example 2065 2066@item -netdev hubport,id=@var{id},hubid=@var{hubid} 2067 2068Create a hub port on QEMU "vlan" @var{hubid}. 2069 2070The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single 2071netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the 2072required hub automatically. 2073 2074@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n] 2075 2076Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should 2077be a unix domain socket backed one. The vhost-user uses a specifically defined 2078protocol to pass vhost ioctl replacement messages to an application on the other 2079end of the socket. On non-MSIX guests, the feature can be forced with 2080@var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to 2081be created for multiqueue vhost-user. 2082 2083Example: 2084@example 2085qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \ 2086 -numa node,memdev=mem \ 2087 -chardev socket,path=/path/to/socket \ 2088 -netdev type=vhost-user,id=net0,chardev=chr0 \ 2089 -device virtio-net-pci,netdev=net0 2090@end example 2091 2092@item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}] 2093Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default). 2094At most @var{len} bytes (64k by default) per packet are stored. The file format is 2095libpcap, so it can be analyzed with tools such as tcpdump or Wireshark. 2096Note: For devices created with '-netdev', use '-object filter-dump,...' instead. 2097 2098@item -net none 2099Indicate that no network devices should be configured. It is used to 2100override the default configuration (@option{-net nic -net user}) which 2101is activated if no @option{-net} options are provided. 2102ETEXI 2103 2104STEXI 2105@end table 2106ETEXI 2107DEFHEADING() 2108 2109DEFHEADING(Character device options:) 2110STEXI 2111 2112The general form of a character device option is: 2113@table @option 2114ETEXI 2115 2116DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, 2117 "-chardev null,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2118 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n" 2119 " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off]\n" 2120 " [,logfile=PATH][,logappend=on|off][,tls-creds=ID] (tcp)\n" 2121 "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds]\n" 2122 " [,mux=on|off][,logfile=PATH][,logappend=on|off] (unix)\n" 2123 "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" 2124 " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n" 2125 " [,logfile=PATH][,logappend=on|off]\n" 2126 "-chardev msmouse,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2127 "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n" 2128 " [,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2129 "-chardev ringbuf,id=id[,size=size][,logfile=PATH][,logappend=on|off]\n" 2130 "-chardev file,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2131 "-chardev pipe,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2132#ifdef _WIN32 2133 "-chardev console,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2134 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2135#else 2136 "-chardev pty,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2137 "-chardev stdio,id=id[,mux=on|off][,signal=on|off][,logfile=PATH][,logappend=on|off]\n" 2138#endif 2139#ifdef CONFIG_BRLAPI 2140 "-chardev braille,id=id[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2141#endif 2142#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ 2143 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) 2144 "-chardev serial,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2145 "-chardev tty,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2146#endif 2147#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) 2148 "-chardev parallel,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2149 "-chardev parport,id=id,path=path[,mux=on|off][,logfile=PATH][,logappend=on|off]\n" 2150#endif 2151#if defined(CONFIG_SPICE) 2152 "-chardev spicevmc,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2153 "-chardev spiceport,id=id,name=name[,debug=debug][,logfile=PATH][,logappend=on|off]\n" 2154#endif 2155 , QEMU_ARCH_ALL 2156) 2157 2158STEXI 2159@item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}] 2160@findex -chardev 2161Backend is one of: 2162@option{null}, 2163@option{socket}, 2164@option{udp}, 2165@option{msmouse}, 2166@option{vc}, 2167@option{ringbuf}, 2168@option{file}, 2169@option{pipe}, 2170@option{console}, 2171@option{serial}, 2172@option{pty}, 2173@option{stdio}, 2174@option{braille}, 2175@option{tty}, 2176@option{parallel}, 2177@option{parport}, 2178@option{spicevmc}. 2179@option{spiceport}. 2180The specific backend will determine the applicable options. 2181 2182All devices must have an id, which can be any string up to 127 characters long. 2183It is used to uniquely identify this device in other command line directives. 2184 2185A character device may be used in multiplexing mode by multiple front-ends. 2186Specify @option{mux=on} to enable this mode. 2187A multiplexer is a "1:N" device, and here the "1" end is your specified chardev 2188backend, and the "N" end is the various parts of QEMU that can talk to a chardev. 2189If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will 2190create a multiplexer with your specified ID, and you can then configure multiple 2191front ends to use that chardev ID for their input/output. Up to four different 2192front ends can be connected to a single multiplexed chardev. (Without 2193multiplexing enabled, a chardev can only be used by a single front end.) 2194For instance you could use this to allow a single stdio chardev to be used by 2195two serial ports and the QEMU monitor: 2196 2197@example 2198-chardev stdio,mux=on,id=char0 \ 2199-mon chardev=char0,mode=readline,default \ 2200-serial chardev:char0 \ 2201-serial chardev:char0 2202@end example 2203 2204You can have more than one multiplexer in a system configuration; for instance 2205you could have a TCP port multiplexed between UART 0 and UART 1, and stdio 2206multiplexed between the QEMU monitor and a parallel port: 2207 2208@example 2209-chardev stdio,mux=on,id=char0 \ 2210-mon chardev=char0,mode=readline,default \ 2211-parallel chardev:char0 \ 2212-chardev tcp,...,mux=on,id=char1 \ 2213-serial chardev:char1 \ 2214-serial chardev:char1 2215@end example 2216 2217When you're using a multiplexed character device, some escape sequences are 2218interpreted in the input. @xref{mux_keys, Keys in the character backend 2219multiplexer}. 2220 2221Note that some other command line options may implicitly create multiplexed 2222character backends; for instance @option{-serial mon:stdio} creates a 2223multiplexed stdio backend connected to the serial port and the QEMU monitor, 2224and @option{-nographic} also multiplexes the console and the monitor to 2225stdio. 2226 2227There is currently no support for multiplexing in the other direction 2228(where a single QEMU front end takes input and output from multiple chardevs). 2229 2230Every backend supports the @option{logfile} option, which supplies the path 2231to a file to record all data transmitted via the backend. The @option{logappend} 2232option controls whether the log file will be truncated or appended to when 2233opened. 2234 2235Further options to each backend are described below. 2236 2237@item -chardev null ,id=@var{id} 2238A void device. This device will not emit any data, and will drop any data it 2239receives. The null backend does not take any options. 2240 2241@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}] [,tls-creds=@var{id}] 2242 2243Create a two-way stream socket, which can be either a TCP or a unix socket. A 2244unix socket will be created if @option{path} is specified. Behaviour is 2245undefined if TCP options are specified for a unix socket. 2246 2247@option{server} specifies that the socket shall be a listening socket. 2248 2249@option{nowait} specifies that QEMU should not block waiting for a client to 2250connect to a listening socket. 2251 2252@option{telnet} specifies that traffic on the socket should interpret telnet 2253escape sequences. 2254 2255@option{reconnect} sets the timeout for reconnecting on non-server sockets when 2256the remote end goes away. qemu will delay this many seconds and then attempt 2257to reconnect. Zero disables reconnecting, and is the default. 2258 2259@option{tls-creds} requests enablement of the TLS protocol for encryption, 2260and specifies the id of the TLS credentials to use for the handshake. The 2261credentials must be previously created with the @option{-object tls-creds} 2262argument. 2263 2264TCP and unix socket options are given below: 2265 2266@table @option 2267 2268@item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay] 2269 2270@option{host} for a listening socket specifies the local address to be bound. 2271For a connecting socket species the remote host to connect to. @option{host} is 2272optional for listening sockets. If not specified it defaults to @code{0.0.0.0}. 2273 2274@option{port} for a listening socket specifies the local port to be bound. For a 2275connecting socket specifies the port on the remote host to connect to. 2276@option{port} can be given as either a port number or a service name. 2277@option{port} is required. 2278 2279@option{to} is only relevant to listening sockets. If it is specified, and 2280@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up 2281to and including @option{to} until it succeeds. @option{to} must be specified 2282as a port number. 2283 2284@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2285If neither is specified the socket may use either protocol. 2286 2287@option{nodelay} disables the Nagle algorithm. 2288 2289@item unix options: path=@var{path} 2290 2291@option{path} specifies the local path of the unix socket. @option{path} is 2292required. 2293 2294@end table 2295 2296@item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6] 2297 2298Sends all traffic from the guest to a remote host over UDP. 2299 2300@option{host} specifies the remote host to connect to. If not specified it 2301defaults to @code{localhost}. 2302 2303@option{port} specifies the port on the remote host to connect to. @option{port} 2304is required. 2305 2306@option{localaddr} specifies the local address to bind to. If not specified it 2307defaults to @code{0.0.0.0}. 2308 2309@option{localport} specifies the local port to bind to. If not specified any 2310available local port will be used. 2311 2312@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. 2313If neither is specified the device may use either protocol. 2314 2315@item -chardev msmouse ,id=@var{id} 2316 2317Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not 2318take any options. 2319 2320@item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]] 2321 2322Connect to a QEMU text console. @option{vc} may optionally be given a specific 2323size. 2324 2325@option{width} and @option{height} specify the width and height respectively of 2326the console, in pixels. 2327 2328@option{cols} and @option{rows} specify that the console be sized to fit a text 2329console with the given dimensions. 2330 2331@item -chardev ringbuf ,id=@var{id} [,size=@var{size}] 2332 2333Create a ring buffer with fixed size @option{size}. 2334@var{size} must be a power of two, and defaults to @code{64K}). 2335 2336@item -chardev file ,id=@var{id} ,path=@var{path} 2337 2338Log all traffic received from the guest to a file. 2339 2340@option{path} specifies the path of the file to be opened. This file will be 2341created if it does not already exist, and overwritten if it does. @option{path} 2342is required. 2343 2344@item -chardev pipe ,id=@var{id} ,path=@var{path} 2345 2346Create a two-way connection to the guest. The behaviour differs slightly between 2347Windows hosts and other hosts: 2348 2349On Windows, a single duplex pipe will be created at 2350@file{\\.pipe\@option{path}}. 2351 2352On other hosts, 2 pipes will be created called @file{@option{path}.in} and 2353@file{@option{path}.out}. Data written to @file{@option{path}.in} will be 2354received by the guest. Data written by the guest can be read from 2355@file{@option{path}.out}. QEMU will not create these fifos, and requires them to 2356be present. 2357 2358@option{path} forms part of the pipe path as described above. @option{path} is 2359required. 2360 2361@item -chardev console ,id=@var{id} 2362 2363Send traffic from the guest to QEMU's standard output. @option{console} does not 2364take any options. 2365 2366@option{console} is only available on Windows hosts. 2367 2368@item -chardev serial ,id=@var{id} ,path=@option{path} 2369 2370Send traffic from the guest to a serial device on the host. 2371 2372On Unix hosts serial will actually accept any tty device, 2373not only serial lines. 2374 2375@option{path} specifies the name of the serial device to open. 2376 2377@item -chardev pty ,id=@var{id} 2378 2379Create a new pseudo-terminal on the host and connect to it. @option{pty} does 2380not take any options. 2381 2382@option{pty} is not available on Windows hosts. 2383 2384@item -chardev stdio ,id=@var{id} [,signal=on|off] 2385Connect to standard input and standard output of the QEMU process. 2386 2387@option{signal} controls if signals are enabled on the terminal, that includes 2388exiting QEMU with the key sequence @key{Control-c}. This option is enabled by 2389default, use @option{signal=off} to disable it. 2390 2391@option{stdio} is not available on Windows hosts. 2392 2393@item -chardev braille ,id=@var{id} 2394 2395Connect to a local BrlAPI server. @option{braille} does not take any options. 2396 2397@item -chardev tty ,id=@var{id} ,path=@var{path} 2398 2399@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and 2400DragonFlyBSD hosts. It is an alias for @option{serial}. 2401 2402@option{path} specifies the path to the tty. @option{path} is required. 2403 2404@item -chardev parallel ,id=@var{id} ,path=@var{path} 2405@itemx -chardev parport ,id=@var{id} ,path=@var{path} 2406 2407@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts. 2408 2409Connect to a local parallel port. 2410 2411@option{path} specifies the path to the parallel port device. @option{path} is 2412required. 2413 2414@item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name} 2415 2416@option{spicevmc} is only available when spice support is built in. 2417 2418@option{debug} debug level for spicevmc 2419 2420@option{name} name of spice channel to connect to 2421 2422Connect to a spice virtual machine channel, such as vdiport. 2423 2424@item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name} 2425 2426@option{spiceport} is only available when spice support is built in. 2427 2428@option{debug} debug level for spicevmc 2429 2430@option{name} name of spice port to connect to 2431 2432Connect to a spice port, allowing a Spice client to handle the traffic 2433identified by a name (preferably a fqdn). 2434ETEXI 2435 2436STEXI 2437@end table 2438ETEXI 2439DEFHEADING() 2440 2441DEFHEADING(Device URL Syntax:) 2442STEXI 2443 2444In addition to using normal file images for the emulated storage devices, 2445QEMU can also use networked resources such as iSCSI devices. These are 2446specified using a special URL syntax. 2447 2448@table @option 2449@item iSCSI 2450iSCSI support allows QEMU to access iSCSI resources directly and use as 2451images for the guest storage. Both disk and cdrom images are supported. 2452 2453Syntax for specifying iSCSI LUNs is 2454``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>'' 2455 2456By default qemu will use the iSCSI initiator-name 2457'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command 2458line or a configuration file. 2459 2460Since version Qemu 2.4 it is possible to specify a iSCSI request timeout to detect 2461stalled requests and force a reestablishment of the session. The timeout 2462is specified in seconds. The default is 0 which means no timeout. Libiscsi 24631.15.0 or greater is required for this feature. 2464 2465Example (without authentication): 2466@example 2467qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \ 2468 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \ 2469 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 2470@end example 2471 2472Example (CHAP username/password via URL): 2473@example 2474qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1 2475@end example 2476 2477Example (CHAP username/password via environment variables): 2478@example 2479LIBISCSI_CHAP_USERNAME="user" \ 2480LIBISCSI_CHAP_PASSWORD="password" \ 2481qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 2482@end example 2483 2484iSCSI support is an optional feature of QEMU and only available when 2485compiled and linked against libiscsi. 2486ETEXI 2487DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi, 2488 "-iscsi [user=user][,password=password]\n" 2489 " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n" 2490 " [,initiator-name=initiator-iqn][,id=target-iqn]\n" 2491 " [,timeout=timeout]\n" 2492 " iSCSI session parameters\n", QEMU_ARCH_ALL) 2493STEXI 2494 2495iSCSI parameters such as username and password can also be specified via 2496a configuration file. See qemu-doc for more information and examples. 2497 2498@item NBD 2499QEMU supports NBD (Network Block Devices) both using TCP protocol as well 2500as Unix Domain Sockets. 2501 2502Syntax for specifying a NBD device using TCP 2503``nbd:<server-ip>:<port>[:exportname=<export>]'' 2504 2505Syntax for specifying a NBD device using Unix Domain Sockets 2506``nbd:unix:<domain-socket>[:exportname=<export>]'' 2507 2508 2509Example for TCP 2510@example 2511qemu-system-i386 --drive file=nbd:192.0.2.1:30000 2512@end example 2513 2514Example for Unix Domain Sockets 2515@example 2516qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket 2517@end example 2518 2519@item SSH 2520QEMU supports SSH (Secure Shell) access to remote disks. 2521 2522Examples: 2523@example 2524qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img 2525qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img 2526@end example 2527 2528Currently authentication must be done using ssh-agent. Other 2529authentication methods may be supported in future. 2530 2531@item Sheepdog 2532Sheepdog is a distributed storage system for QEMU. 2533QEMU supports using either local sheepdog devices or remote networked 2534devices. 2535 2536Syntax for specifying a sheepdog device 2537@example 2538sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag] 2539@end example 2540 2541Example 2542@example 2543qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine 2544@end example 2545 2546See also @url{http://http://www.osrg.net/sheepdog/}. 2547 2548@item GlusterFS 2549GlusterFS is an user space distributed file system. 2550QEMU supports the use of GlusterFS volumes for hosting VM disk images using 2551TCP, Unix Domain Sockets and RDMA transport protocols. 2552 2553Syntax for specifying a VM disk image on GlusterFS volume is 2554@example 2555gluster[+transport]://[server[:port]]/volname/image[?socket=...] 2556@end example 2557 2558 2559Example 2560@example 2561qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img 2562@end example 2563 2564See also @url{http://www.gluster.org}. 2565 2566@item HTTP/HTTPS/FTP/FTPS/TFTP 2567QEMU supports read-only access to files accessed over http(s), ftp(s) and tftp. 2568 2569Syntax using a single filename: 2570@example 2571<protocol>://[<username>[:<password>]@@]<host>/<path> 2572@end example 2573 2574where: 2575@table @option 2576@item protocol 2577'http', 'https', 'ftp', 'ftps', or 'tftp'. 2578 2579@item username 2580Optional username for authentication to the remote server. 2581 2582@item password 2583Optional password for authentication to the remote server. 2584 2585@item host 2586Address of the remote server. 2587 2588@item path 2589Path on the remote server, including any query string. 2590@end table 2591 2592The following options are also supported: 2593@table @option 2594@item url 2595The full URL when passing options to the driver explicitly. 2596 2597@item readahead 2598The amount of data to read ahead with each range request to the remote server. 2599This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it 2600does not have a suffix, it will be assumed to be in bytes. The value must be a 2601multiple of 512 bytes. It defaults to 256k. 2602 2603@item sslverify 2604Whether to verify the remote server's certificate when connecting over SSL. It 2605can have the value 'on' or 'off'. It defaults to 'on'. 2606 2607@item cookie 2608Send this cookie (it can also be a list of cookies separated by ';') with 2609each outgoing request. Only supported when using protocols such as HTTP 2610which support cookies, otherwise ignored. 2611 2612@item timeout 2613Set the timeout in seconds of the CURL connection. This timeout is the time 2614that CURL waits for a response from the remote server to get the size of the 2615image to be downloaded. If not set, the default timeout of 5 seconds is used. 2616@end table 2617 2618Note that when passing options to qemu explicitly, @option{driver} is the value 2619of <protocol>. 2620 2621Example: boot from a remote Fedora 20 live ISO image 2622@example 2623qemu-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 2624 2625qemu-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 2626@end example 2627 2628Example: boot from a remote Fedora 20 cloud image using a local overlay for 2629writes, copy-on-read, and a readahead of 64k 2630@example 2631qemu-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 2632 2633qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on 2634@end example 2635 2636Example: boot from an image stored on a VMware vSphere server with a self-signed 2637certificate using a local overlay for writes, a readahead of 64k and a timeout 2638of 10 seconds. 2639@example 2640qemu-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 2641 2642qemu-system-x86_64 -drive file=/tmp/test.qcow2 2643@end example 2644ETEXI 2645 2646STEXI 2647@end table 2648ETEXI 2649 2650DEFHEADING(Bluetooth(R) options:) 2651STEXI 2652@table @option 2653ETEXI 2654 2655DEF("bt", HAS_ARG, QEMU_OPTION_bt, \ 2656 "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \ 2657 "-bt hci,host[:id]\n" \ 2658 " use host's HCI with the given name\n" \ 2659 "-bt hci[,vlan=n]\n" \ 2660 " emulate a standard HCI in virtual scatternet 'n'\n" \ 2661 "-bt vhci[,vlan=n]\n" \ 2662 " add host computer to virtual scatternet 'n' using VHCI\n" \ 2663 "-bt device:dev[,vlan=n]\n" \ 2664 " emulate a bluetooth device 'dev' in scatternet 'n'\n", 2665 QEMU_ARCH_ALL) 2666STEXI 2667@item -bt hci[...] 2668@findex -bt 2669Defines the function of the corresponding Bluetooth HCI. -bt options 2670are matched with the HCIs present in the chosen machine type. For 2671example when emulating a machine with only one HCI built into it, only 2672the first @code{-bt hci[...]} option is valid and defines the HCI's 2673logic. The Transport Layer is decided by the machine type. Currently 2674the machines @code{n800} and @code{n810} have one HCI and all other 2675machines have none. 2676 2677@anchor{bt-hcis} 2678The following three types are recognized: 2679 2680@table @option 2681@item -bt hci,null 2682(default) The corresponding Bluetooth HCI assumes no internal logic 2683and will not respond to any HCI commands or emit events. 2684 2685@item -bt hci,host[:@var{id}] 2686(@code{bluez} only) The corresponding HCI passes commands / events 2687to / from the physical HCI identified by the name @var{id} (default: 2688@code{hci0}) on the computer running QEMU. Only available on @code{bluez} 2689capable systems like Linux. 2690 2691@item -bt hci[,vlan=@var{n}] 2692Add a virtual, standard HCI that will participate in the Bluetooth 2693scatternet @var{n} (default @code{0}). Similarly to @option{-net} 2694VLANs, devices inside a bluetooth network @var{n} can only communicate 2695with other devices in the same network (scatternet). 2696@end table 2697 2698@item -bt vhci[,vlan=@var{n}] 2699(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached 2700to the host bluetooth stack instead of to the emulated target. This 2701allows the host and target machines to participate in a common scatternet 2702and communicate. Requires the Linux @code{vhci} driver installed. Can 2703be used as following: 2704 2705@example 2706qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5 2707@end example 2708 2709@item -bt device:@var{dev}[,vlan=@var{n}] 2710Emulate a bluetooth device @var{dev} and place it in network @var{n} 2711(default @code{0}). QEMU can only emulate one type of bluetooth devices 2712currently: 2713 2714@table @option 2715@item keyboard 2716Virtual wireless keyboard implementing the HIDP bluetooth profile. 2717@end table 2718ETEXI 2719 2720STEXI 2721@end table 2722ETEXI 2723DEFHEADING() 2724 2725#ifdef CONFIG_TPM 2726DEFHEADING(TPM device options:) 2727 2728DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \ 2729 "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n" 2730 " use path to provide path to a character device; default is /dev/tpm0\n" 2731 " use cancel-path to provide path to TPM's cancel sysfs entry; if\n" 2732 " not provided it will be searched for in /sys/class/misc/tpm?/device\n", 2733 QEMU_ARCH_ALL) 2734STEXI 2735 2736The general form of a TPM device option is: 2737@table @option 2738 2739@item -tpmdev @var{backend} ,id=@var{id} [,@var{options}] 2740@findex -tpmdev 2741Backend type must be: 2742@option{passthrough}. 2743 2744The specific backend type will determine the applicable options. 2745The @code{-tpmdev} option creates the TPM backend and requires a 2746@code{-device} option that specifies the TPM frontend interface model. 2747 2748Options to each backend are described below. 2749 2750Use 'help' to print all available TPM backend types. 2751@example 2752qemu -tpmdev help 2753@end example 2754 2755@item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path} 2756 2757(Linux-host only) Enable access to the host's TPM using the passthrough 2758driver. 2759 2760@option{path} specifies the path to the host's TPM device, i.e., on 2761a Linux host this would be @code{/dev/tpm0}. 2762@option{path} is optional and by default @code{/dev/tpm0} is used. 2763 2764@option{cancel-path} specifies the path to the host TPM device's sysfs 2765entry allowing for cancellation of an ongoing TPM command. 2766@option{cancel-path} is optional and by default QEMU will search for the 2767sysfs entry to use. 2768 2769Some notes about using the host's TPM with the passthrough driver: 2770 2771The TPM device accessed by the passthrough driver must not be 2772used by any other application on the host. 2773 2774Since the host's firmware (BIOS/UEFI) has already initialized the TPM, 2775the VM's firmware (BIOS/UEFI) will not be able to initialize the 2776TPM again and may therefore not show a TPM-specific menu that would 2777otherwise allow the user to configure the TPM, e.g., allow the user to 2778enable/disable or activate/deactivate the TPM. 2779Further, if TPM ownership is released from within a VM then the host's TPM 2780will get disabled and deactivated. To enable and activate the 2781TPM again afterwards, the host has to be rebooted and the user is 2782required to enter the firmware's menu to enable and activate the TPM. 2783If the TPM is left disabled and/or deactivated most TPM commands will fail. 2784 2785To create a passthrough TPM use the following two options: 2786@example 2787-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0 2788@end example 2789Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by 2790@code{tpmdev=tpm0} in the device option. 2791 2792@end table 2793 2794ETEXI 2795 2796DEFHEADING() 2797 2798#endif 2799 2800DEFHEADING(Linux/Multiboot boot specific:) 2801STEXI 2802 2803When using these options, you can use a given Linux or Multiboot 2804kernel without installing it in the disk image. It can be useful 2805for easier testing of various kernels. 2806 2807@table @option 2808ETEXI 2809 2810DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \ 2811 "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL) 2812STEXI 2813@item -kernel @var{bzImage} 2814@findex -kernel 2815Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel 2816or in multiboot format. 2817ETEXI 2818 2819DEF("append", HAS_ARG, QEMU_OPTION_append, \ 2820 "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL) 2821STEXI 2822@item -append @var{cmdline} 2823@findex -append 2824Use @var{cmdline} as kernel command line 2825ETEXI 2826 2827DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \ 2828 "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL) 2829STEXI 2830@item -initrd @var{file} 2831@findex -initrd 2832Use @var{file} as initial ram disk. 2833 2834@item -initrd "@var{file1} arg=foo,@var{file2}" 2835 2836This syntax is only available with multiboot. 2837 2838Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the 2839first module. 2840ETEXI 2841 2842DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \ 2843 "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL) 2844STEXI 2845@item -dtb @var{file} 2846@findex -dtb 2847Use @var{file} as a device tree binary (dtb) image and pass it to the kernel 2848on boot. 2849ETEXI 2850 2851STEXI 2852@end table 2853ETEXI 2854DEFHEADING() 2855 2856DEFHEADING(Debug/Expert options:) 2857STEXI 2858@table @option 2859ETEXI 2860 2861DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg, 2862 "-fw_cfg [name=]<name>,file=<file>\n" 2863 " add named fw_cfg entry from file\n" 2864 "-fw_cfg [name=]<name>,string=<str>\n" 2865 " add named fw_cfg entry from string\n", 2866 QEMU_ARCH_ALL) 2867STEXI 2868@item -fw_cfg [name=]@var{name},file=@var{file} 2869@findex -fw_cfg 2870Add named fw_cfg entry from file. @var{name} determines the name of 2871the entry in the fw_cfg file directory exposed to the guest. 2872 2873@item -fw_cfg [name=]@var{name},string=@var{str} 2874Add named fw_cfg entry from string. 2875ETEXI 2876 2877DEF("serial", HAS_ARG, QEMU_OPTION_serial, \ 2878 "-serial dev redirect the serial port to char device 'dev'\n", 2879 QEMU_ARCH_ALL) 2880STEXI 2881@item -serial @var{dev} 2882@findex -serial 2883Redirect the virtual serial port to host character device 2884@var{dev}. The default device is @code{vc} in graphical mode and 2885@code{stdio} in non graphical mode. 2886 2887This option can be used several times to simulate up to 4 serial 2888ports. 2889 2890Use @code{-serial none} to disable all serial ports. 2891 2892Available character devices are: 2893@table @option 2894@item vc[:@var{W}x@var{H}] 2895Virtual console. Optionally, a width and height can be given in pixel with 2896@example 2897vc:800x600 2898@end example 2899It is also possible to specify width or height in characters: 2900@example 2901vc:80Cx24C 2902@end example 2903@item pty 2904[Linux only] Pseudo TTY (a new PTY is automatically allocated) 2905@item none 2906No device is allocated. 2907@item null 2908void device 2909@item chardev:@var{id} 2910Use a named character device defined with the @code{-chardev} option. 2911@item /dev/XXX 2912[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port 2913parameters are set according to the emulated ones. 2914@item /dev/parport@var{N} 2915[Linux only, parallel port only] Use host parallel port 2916@var{N}. Currently SPP and EPP parallel port features can be used. 2917@item file:@var{filename} 2918Write output to @var{filename}. No character can be read. 2919@item stdio 2920[Unix only] standard input/output 2921@item pipe:@var{filename} 2922name pipe @var{filename} 2923@item COM@var{n} 2924[Windows only] Use host serial port @var{n} 2925@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}] 2926This implements UDP Net Console. 2927When @var{remote_host} or @var{src_ip} are not specified 2928they default to @code{0.0.0.0}. 2929When not using a specified @var{src_port} a random port is automatically chosen. 2930 2931If you just want a simple readonly console you can use @code{netcat} or 2932@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as: 2933@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it 2934will appear in the netconsole session. 2935 2936If you plan to send characters back via netconsole or you want to stop 2937and start QEMU a lot of times, you should have QEMU use the same 2938source port each time by using something like @code{-serial 2939udp::4555@@:4556} to QEMU. Another approach is to use a patched 2940version of netcat which can listen to a TCP port and send and receive 2941characters via udp. If you have a patched version of netcat which 2942activates telnet remote echo and single char transfer, then you can 2943use the following options to step up a netcat redirector to allow 2944telnet on port 5555 to access the QEMU port. 2945@table @code 2946@item QEMU Options: 2947-serial udp::4555@@:4556 2948@item netcat options: 2949-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T 2950@item telnet options: 2951localhost 5555 2952@end table 2953 2954@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}] 2955The TCP Net Console has two modes of operation. It can send the serial 2956I/O to a location or wait for a connection from a location. By default 2957the TCP Net Console is sent to @var{host} at the @var{port}. If you use 2958the @var{server} option QEMU will wait for a client socket application 2959to connect to the port before continuing, unless the @code{nowait} 2960option was specified. The @code{nodelay} option disables the Nagle buffering 2961algorithm. The @code{reconnect} option only applies if @var{noserver} is 2962set, if the connection goes down it will attempt to reconnect at the 2963given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only 2964one TCP connection at a time is accepted. You can use @code{telnet} to 2965connect to the corresponding character device. 2966@table @code 2967@item Example to send tcp console to 192.168.0.2 port 4444 2968-serial tcp:192.168.0.2:4444 2969@item Example to listen and wait on port 4444 for connection 2970-serial tcp::4444,server 2971@item Example to not wait and listen on ip 192.168.0.100 port 4444 2972-serial tcp:192.168.0.100:4444,server,nowait 2973@end table 2974 2975@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay] 2976The telnet protocol is used instead of raw tcp sockets. The options 2977work the same as if you had specified @code{-serial tcp}. The 2978difference is that the port acts like a telnet server or client using 2979telnet option negotiation. This will also allow you to send the 2980MAGIC_SYSRQ sequence if you use a telnet that supports sending the break 2981sequence. Typically in unix telnet you do it with Control-] and then 2982type "send break" followed by pressing the enter key. 2983 2984@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}] 2985A unix domain socket is used instead of a tcp socket. The option works the 2986same as if you had specified @code{-serial tcp} except the unix domain socket 2987@var{path} is used for connections. 2988 2989@item mon:@var{dev_string} 2990This is a special option to allow the monitor to be multiplexed onto 2991another serial port. The monitor is accessed with key sequence of 2992@key{Control-a} and then pressing @key{c}. 2993@var{dev_string} should be any one of the serial devices specified 2994above. An example to multiplex the monitor onto a telnet server 2995listening on port 4444 would be: 2996@table @code 2997@item -serial mon:telnet::4444,server,nowait 2998@end table 2999When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate 3000QEMU any more but will be passed to the guest instead. 3001 3002@item braille 3003Braille device. This will use BrlAPI to display the braille output on a real 3004or fake device. 3005 3006@item msmouse 3007Three button serial mouse. Configure the guest to use Microsoft protocol. 3008@end table 3009ETEXI 3010 3011DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \ 3012 "-parallel dev redirect the parallel port to char device 'dev'\n", 3013 QEMU_ARCH_ALL) 3014STEXI 3015@item -parallel @var{dev} 3016@findex -parallel 3017Redirect the virtual parallel port to host device @var{dev} (same 3018devices as the serial port). On Linux hosts, @file{/dev/parportN} can 3019be used to use hardware devices connected on the corresponding host 3020parallel port. 3021 3022This option can be used several times to simulate up to 3 parallel 3023ports. 3024 3025Use @code{-parallel none} to disable all parallel ports. 3026ETEXI 3027 3028DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \ 3029 "-monitor dev redirect the monitor to char device 'dev'\n", 3030 QEMU_ARCH_ALL) 3031STEXI 3032@item -monitor @var{dev} 3033@findex -monitor 3034Redirect the monitor to host device @var{dev} (same devices as the 3035serial port). 3036The default device is @code{vc} in graphical mode and @code{stdio} in 3037non graphical mode. 3038Use @code{-monitor none} to disable the default monitor. 3039ETEXI 3040DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \ 3041 "-qmp dev like -monitor but opens in 'control' mode\n", 3042 QEMU_ARCH_ALL) 3043STEXI 3044@item -qmp @var{dev} 3045@findex -qmp 3046Like -monitor but opens in 'control' mode. 3047ETEXI 3048DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \ 3049 "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n", 3050 QEMU_ARCH_ALL) 3051STEXI 3052@item -qmp-pretty @var{dev} 3053@findex -qmp-pretty 3054Like -qmp but uses pretty JSON formatting. 3055ETEXI 3056 3057DEF("mon", HAS_ARG, QEMU_OPTION_mon, \ 3058 "-mon [chardev=]name[,mode=readline|control][,default]\n", QEMU_ARCH_ALL) 3059STEXI 3060@item -mon [chardev=]name[,mode=readline|control][,default] 3061@findex -mon 3062Setup monitor on chardev @var{name}. 3063ETEXI 3064 3065DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ 3066 "-debugcon dev redirect the debug console to char device 'dev'\n", 3067 QEMU_ARCH_ALL) 3068STEXI 3069@item -debugcon @var{dev} 3070@findex -debugcon 3071Redirect the debug console to host device @var{dev} (same devices as the 3072serial port). The debug console is an I/O port which is typically port 30730xe9; writing to that I/O port sends output to this device. 3074The default device is @code{vc} in graphical mode and @code{stdio} in 3075non graphical mode. 3076ETEXI 3077 3078DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ 3079 "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL) 3080STEXI 3081@item -pidfile @var{file} 3082@findex -pidfile 3083Store the QEMU process PID in @var{file}. It is useful if you launch QEMU 3084from a script. 3085ETEXI 3086 3087DEF("singlestep", 0, QEMU_OPTION_singlestep, \ 3088 "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) 3089STEXI 3090@item -singlestep 3091@findex -singlestep 3092Run the emulation in single step mode. 3093ETEXI 3094 3095DEF("S", 0, QEMU_OPTION_S, \ 3096 "-S freeze CPU at startup (use 'c' to start execution)\n", 3097 QEMU_ARCH_ALL) 3098STEXI 3099@item -S 3100@findex -S 3101Do not start CPU at startup (you must type 'c' in the monitor). 3102ETEXI 3103 3104DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, 3105 "-realtime [mlock=on|off]\n" 3106 " run qemu with realtime features\n" 3107 " mlock=on|off controls mlock support (default: on)\n", 3108 QEMU_ARCH_ALL) 3109STEXI 3110@item -realtime mlock=on|off 3111@findex -realtime 3112Run qemu with realtime features. 3113mlocking qemu and guest memory can be enabled via @option{mlock=on} 3114(enabled by default). 3115ETEXI 3116 3117DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ 3118 "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) 3119STEXI 3120@item -gdb @var{dev} 3121@findex -gdb 3122Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical 3123connections will likely be TCP-based, but also UDP, pseudo TTY, or even 3124stdio are reasonable use case. The latter is allowing to start QEMU from 3125within gdb and establish the connection via a pipe: 3126@example 3127(gdb) target remote | exec qemu-system-i386 -gdb stdio ... 3128@end example 3129ETEXI 3130 3131DEF("s", 0, QEMU_OPTION_s, \ 3132 "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n", 3133 QEMU_ARCH_ALL) 3134STEXI 3135@item -s 3136@findex -s 3137Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234 3138(@pxref{gdb_usage}). 3139ETEXI 3140 3141DEF("d", HAS_ARG, QEMU_OPTION_d, \ 3142 "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n", 3143 QEMU_ARCH_ALL) 3144STEXI 3145@item -d @var{item1}[,...] 3146@findex -d 3147Enable logging of specified items. Use '-d help' for a list of log items. 3148ETEXI 3149 3150DEF("D", HAS_ARG, QEMU_OPTION_D, \ 3151 "-D logfile output log to logfile (default stderr)\n", 3152 QEMU_ARCH_ALL) 3153STEXI 3154@item -D @var{logfile} 3155@findex -D 3156Output log in @var{logfile} instead of to stderr 3157ETEXI 3158 3159DEF("dfilter", HAS_ARG, QEMU_OPTION_DFILTER, \ 3160 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n", 3161 QEMU_ARCH_ALL) 3162STEXI 3163@item -dfilter @var{range1}[,...] 3164@findex -dfilter 3165Filter debug output to that relevant to a range of target addresses. The filter 3166spec can be either @var{start}+@var{size}, @var{start}-@var{size} or 3167@var{start}..@var{end} where @var{start} @var{end} and @var{size} are the 3168addresses and sizes required. For example: 3169@example 3170 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000 3171@end example 3172Will dump output for any code in the 0x1000 sized block starting at 0x8000 and 3173the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized 3174block starting at 0xffffffc00005f000. 3175ETEXI 3176 3177DEF("L", HAS_ARG, QEMU_OPTION_L, \ 3178 "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", 3179 QEMU_ARCH_ALL) 3180STEXI 3181@item -L @var{path} 3182@findex -L 3183Set the directory for the BIOS, VGA BIOS and keymaps. 3184ETEXI 3185 3186DEF("bios", HAS_ARG, QEMU_OPTION_bios, \ 3187 "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL) 3188STEXI 3189@item -bios @var{file} 3190@findex -bios 3191Set the filename for the BIOS. 3192ETEXI 3193 3194DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \ 3195 "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL) 3196STEXI 3197@item -enable-kvm 3198@findex -enable-kvm 3199Enable KVM full virtualization support. This option is only available 3200if KVM support is enabled when compiling. 3201ETEXI 3202 3203DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, 3204 "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) 3205DEF("xen-create", 0, QEMU_OPTION_xen_create, 3206 "-xen-create create domain using xen hypercalls, bypassing xend\n" 3207 " warning: should not be used when xend is in use\n", 3208 QEMU_ARCH_ALL) 3209DEF("xen-attach", 0, QEMU_OPTION_xen_attach, 3210 "-xen-attach attach to existing xen domain\n" 3211 " xend will use this when starting QEMU\n", 3212 QEMU_ARCH_ALL) 3213STEXI 3214@item -xen-domid @var{id} 3215@findex -xen-domid 3216Specify xen guest domain @var{id} (XEN only). 3217@item -xen-create 3218@findex -xen-create 3219Create domain using xen hypercalls, bypassing xend. 3220Warning: should not be used when xend is in use (XEN only). 3221@item -xen-attach 3222@findex -xen-attach 3223Attach to existing xen domain. 3224xend will use this when starting QEMU (XEN only). 3225ETEXI 3226 3227DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \ 3228 "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL) 3229STEXI 3230@item -no-reboot 3231@findex -no-reboot 3232Exit instead of rebooting. 3233ETEXI 3234 3235DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \ 3236 "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL) 3237STEXI 3238@item -no-shutdown 3239@findex -no-shutdown 3240Don't exit QEMU on guest shutdown, but instead only stop the emulation. 3241This allows for instance switching to monitor to commit changes to the 3242disk image. 3243ETEXI 3244 3245DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ 3246 "-loadvm [tag|id]\n" \ 3247 " start right away with a saved state (loadvm in monitor)\n", 3248 QEMU_ARCH_ALL) 3249STEXI 3250@item -loadvm @var{file} 3251@findex -loadvm 3252Start right away with a saved state (@code{loadvm} in monitor) 3253ETEXI 3254 3255#ifndef _WIN32 3256DEF("daemonize", 0, QEMU_OPTION_daemonize, \ 3257 "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) 3258#endif 3259STEXI 3260@item -daemonize 3261@findex -daemonize 3262Daemonize the QEMU process after initialization. QEMU will not detach from 3263standard IO until it is ready to receive connections on any of its devices. 3264This option is a useful way for external programs to launch QEMU without having 3265to cope with initialization race conditions. 3266ETEXI 3267 3268DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \ 3269 "-option-rom rom load a file, rom, into the option ROM space\n", 3270 QEMU_ARCH_ALL) 3271STEXI 3272@item -option-rom @var{file} 3273@findex -option-rom 3274Load the contents of @var{file} as an option ROM. 3275This option is useful to load things like EtherBoot. 3276ETEXI 3277 3278HXCOMM Silently ignored for compatibility 3279DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL) 3280 3281HXCOMM Options deprecated by -rtc 3282DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL) 3283DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL) 3284 3285DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \ 3286 "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \ 3287 " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n", 3288 QEMU_ARCH_ALL) 3289 3290STEXI 3291 3292@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew] 3293@findex -rtc 3294Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current 3295UTC or local time, respectively. @code{localtime} is required for correct date in 3296MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the 3297format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC. 3298 3299By default the RTC is driven by the host system time. This allows using of the 3300RTC as accurate reference clock inside the guest, specifically if the host 3301time is smoothly following an accurate external reference clock, e.g. via NTP. 3302If you want to isolate the guest time from the host, you can set @option{clock} 3303to @code{rt} instead. To even prevent it from progressing during suspension, 3304you can set it to @code{vm}. 3305 3306Enable @option{driftfix} (i386 targets only) if you experience time drift problems, 3307specifically with Windows' ACPI HAL. This option will try to figure out how 3308many timer interrupts were not processed by the Windows guest and will 3309re-inject them. 3310ETEXI 3311 3312DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ 3313 "-icount [shift=N|auto][,align=on|off][,sleep=on|off,rr=record|replay,rrfile=<filename>]\n" \ 3314 " enable virtual instruction counter with 2^N clock ticks per\n" \ 3315 " instruction, enable aligning the host and virtual clocks\n" \ 3316 " or disable real time cpu sleeping\n", QEMU_ARCH_ALL) 3317STEXI 3318@item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename}] 3319@findex -icount 3320Enable virtual instruction counter. The virtual cpu will execute one 3321instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified 3322then the virtual cpu speed will be automatically adjusted to keep virtual 3323time within a few seconds of real time. 3324 3325When the virtual cpu is sleeping, the virtual time will advance at default 3326speed unless @option{sleep=on|off} is specified. 3327With @option{sleep=on|off}, the virtual time will jump to the next timer deadline 3328instantly whenever the virtual cpu goes to sleep mode and will not advance 3329if no timer is enabled. This behavior give deterministic execution times from 3330the guest point of view. 3331 3332Note that while this option can give deterministic behavior, it does not 3333provide cycle accurate emulation. Modern CPUs contain superscalar out of 3334order cores with complex cache hierarchies. The number of instructions 3335executed often has little or no correlation with actual performance. 3336 3337@option{align=on} will activate the delay algorithm which will try 3338to synchronise the host clock and the virtual clock. The goal is to 3339have a guest running at the real frequency imposed by the shift option. 3340Whenever the guest clock is behind the host clock and if 3341@option{align=on} is specified then we print a message to the user 3342to inform about the delay. 3343Currently this option does not work when @option{shift} is @code{auto}. 3344Note: The sync algorithm will work for those shift values for which 3345the guest clock runs ahead of the host clock. Typically this happens 3346when the shift value is high (how high depends on the host machine). 3347 3348When @option{rr} option is specified deterministic record/replay is enabled. 3349Replay log is written into @var{filename} file in record mode and 3350read from this file in replay mode. 3351ETEXI 3352 3353DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ 3354 "-watchdog model\n" \ 3355 " enable virtual hardware watchdog [default=none]\n", 3356 QEMU_ARCH_ALL) 3357STEXI 3358@item -watchdog @var{model} 3359@findex -watchdog 3360Create a virtual hardware watchdog device. Once enabled (by a guest 3361action), the watchdog must be periodically polled by an agent inside 3362the guest or else the guest will be restarted. Choose a model for 3363which your guest has drivers. 3364 3365The @var{model} is the model of hardware watchdog to emulate. Use 3366@code{-watchdog help} to list available hardware models. Only one 3367watchdog can be enabled for a guest. 3368 3369The following models may be available: 3370@table @option 3371@item ib700 3372iBASE 700 is a very simple ISA watchdog with a single timer. 3373@item i6300esb 3374Intel 6300ESB I/O controller hub is a much more featureful PCI-based 3375dual-timer watchdog. 3376@item diag288 3377A virtual watchdog for s390x backed by the diagnose 288 hypercall 3378(currently KVM only). 3379@end table 3380ETEXI 3381 3382DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \ 3383 "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \ 3384 " action when watchdog fires [default=reset]\n", 3385 QEMU_ARCH_ALL) 3386STEXI 3387@item -watchdog-action @var{action} 3388@findex -watchdog-action 3389 3390The @var{action} controls what QEMU will do when the watchdog timer 3391expires. 3392The default is 3393@code{reset} (forcefully reset the guest). 3394Other possible actions are: 3395@code{shutdown} (attempt to gracefully shutdown the guest), 3396@code{poweroff} (forcefully poweroff the guest), 3397@code{pause} (pause the guest), 3398@code{debug} (print a debug message and continue), or 3399@code{none} (do nothing). 3400 3401Note that the @code{shutdown} action requires that the guest responds 3402to ACPI signals, which it may not be able to do in the sort of 3403situations where the watchdog would have expired, and thus 3404@code{-watchdog-action shutdown} is not recommended for production use. 3405 3406Examples: 3407 3408@table @code 3409@item -watchdog i6300esb -watchdog-action pause 3410@itemx -watchdog ib700 3411@end table 3412ETEXI 3413 3414DEF("echr", HAS_ARG, QEMU_OPTION_echr, \ 3415 "-echr chr set terminal escape character instead of ctrl-a\n", 3416 QEMU_ARCH_ALL) 3417STEXI 3418 3419@item -echr @var{numeric_ascii_value} 3420@findex -echr 3421Change the escape character used for switching to the monitor when using 3422monitor and serial sharing. The default is @code{0x01} when using the 3423@code{-nographic} option. @code{0x01} is equal to pressing 3424@code{Control-a}. You can select a different character from the ascii 3425control keys where 1 through 26 map to Control-a through Control-z. For 3426instance you could use the either of the following to change the escape 3427character to Control-t. 3428@table @code 3429@item -echr 0x14 3430@itemx -echr 20 3431@end table 3432ETEXI 3433 3434DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \ 3435 "-virtioconsole c\n" \ 3436 " set virtio console\n", QEMU_ARCH_ALL) 3437STEXI 3438@item -virtioconsole @var{c} 3439@findex -virtioconsole 3440Set virtio console. 3441 3442This option is maintained for backward compatibility. 3443 3444Please use @code{-device virtconsole} for the new way of invocation. 3445ETEXI 3446 3447DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \ 3448 "-show-cursor show cursor\n", QEMU_ARCH_ALL) 3449STEXI 3450@item -show-cursor 3451@findex -show-cursor 3452Show cursor. 3453ETEXI 3454 3455DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \ 3456 "-tb-size n set TB size\n", QEMU_ARCH_ALL) 3457STEXI 3458@item -tb-size @var{n} 3459@findex -tb-size 3460Set TB size. 3461ETEXI 3462 3463DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \ 3464 "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \ 3465 "-incoming rdma:host:port[,ipv4][,ipv6]\n" \ 3466 "-incoming unix:socketpath\n" \ 3467 " prepare for incoming migration, listen on\n" \ 3468 " specified protocol and socket address\n" \ 3469 "-incoming fd:fd\n" \ 3470 "-incoming exec:cmdline\n" \ 3471 " accept incoming migration on given file descriptor\n" \ 3472 " or from given external command\n" \ 3473 "-incoming defer\n" \ 3474 " wait for the URI to be specified via migrate_incoming\n", 3475 QEMU_ARCH_ALL) 3476STEXI 3477@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6] 3478@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6] 3479@findex -incoming 3480Prepare for incoming migration, listen on a given tcp port. 3481 3482@item -incoming unix:@var{socketpath} 3483Prepare for incoming migration, listen on a given unix socket. 3484 3485@item -incoming fd:@var{fd} 3486Accept incoming migration from a given filedescriptor. 3487 3488@item -incoming exec:@var{cmdline} 3489Accept incoming migration as an output from specified external command. 3490 3491@item -incoming defer 3492Wait for the URI to be specified via migrate_incoming. The monitor can 3493be used to change settings (such as migration parameters) prior to issuing 3494the migrate_incoming to allow the migration to begin. 3495ETEXI 3496 3497DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \ 3498 "-nodefaults don't create default devices\n", QEMU_ARCH_ALL) 3499STEXI 3500@item -nodefaults 3501@findex -nodefaults 3502Don't create default devices. Normally, QEMU sets the default devices like serial 3503port, parallel port, virtual console, monitor device, VGA adapter, floppy and 3504CD-ROM drive and others. The @code{-nodefaults} option will disable all those 3505default devices. 3506ETEXI 3507 3508#ifndef _WIN32 3509DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \ 3510 "-chroot dir chroot to dir just before starting the VM\n", 3511 QEMU_ARCH_ALL) 3512#endif 3513STEXI 3514@item -chroot @var{dir} 3515@findex -chroot 3516Immediately before starting guest execution, chroot to the specified 3517directory. Especially useful in combination with -runas. 3518ETEXI 3519 3520#ifndef _WIN32 3521DEF("runas", HAS_ARG, QEMU_OPTION_runas, \ 3522 "-runas user change to user id user just before starting the VM\n", 3523 QEMU_ARCH_ALL) 3524#endif 3525STEXI 3526@item -runas @var{user} 3527@findex -runas 3528Immediately before starting guest execution, drop root privileges, switching 3529to the specified user. 3530ETEXI 3531 3532DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env, 3533 "-prom-env variable=value\n" 3534 " set OpenBIOS nvram variables\n", 3535 QEMU_ARCH_PPC | QEMU_ARCH_SPARC) 3536STEXI 3537@item -prom-env @var{variable}=@var{value} 3538@findex -prom-env 3539Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only). 3540ETEXI 3541DEF("semihosting", 0, QEMU_OPTION_semihosting, 3542 "-semihosting semihosting mode\n", 3543 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3544 QEMU_ARCH_MIPS) 3545STEXI 3546@item -semihosting 3547@findex -semihosting 3548Enable semihosting mode (ARM, M68K, Xtensa, MIPS only). 3549ETEXI 3550DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config, 3551 "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \ 3552 " semihosting configuration\n", 3553QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | 3554QEMU_ARCH_MIPS) 3555STEXI 3556@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]] 3557@findex -semihosting-config 3558Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only). 3559@table @option 3560@item target=@code{native|gdb|auto} 3561Defines where the semihosting calls will be addressed, to QEMU (@code{native}) 3562or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb} 3563during debug sessions and @code{native} otherwise. 3564@item arg=@var{str1},arg=@var{str2},... 3565Allows the user to pass input arguments, and can be used multiple times to build 3566up a list. The old-style @code{-kernel}/@code{-append} method of passing a 3567command line is still supported for backward compatibility. If both the 3568@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are 3569specified, the former is passed to semihosting as it always takes precedence. 3570@end table 3571ETEXI 3572DEF("old-param", 0, QEMU_OPTION_old_param, 3573 "-old-param old param mode\n", QEMU_ARCH_ARM) 3574STEXI 3575@item -old-param 3576@findex -old-param (ARM) 3577Old param mode (ARM only). 3578ETEXI 3579 3580DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ 3581 "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n", 3582 QEMU_ARCH_ALL) 3583STEXI 3584@item -sandbox @var{arg} 3585@findex -sandbox 3586Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will 3587disable it. The default is 'off'. 3588ETEXI 3589 3590DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, 3591 "-readconfig <file>\n", QEMU_ARCH_ALL) 3592STEXI 3593@item -readconfig @var{file} 3594@findex -readconfig 3595Read device configuration from @var{file}. This approach is useful when you want to spawn 3596QEMU process with many command line options but you don't want to exceed the command line 3597character limit. 3598ETEXI 3599DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig, 3600 "-writeconfig <file>\n" 3601 " read/write config file\n", QEMU_ARCH_ALL) 3602STEXI 3603@item -writeconfig @var{file} 3604@findex -writeconfig 3605Write device configuration to @var{file}. The @var{file} can be either filename to save 3606command line and device configuration into file or dash @code{-}) character to print the 3607output to stdout. This can be later used as input file for @code{-readconfig} option. 3608ETEXI 3609DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, 3610 "-nodefconfig\n" 3611 " do not load default config files at startup\n", 3612 QEMU_ARCH_ALL) 3613STEXI 3614@item -nodefconfig 3615@findex -nodefconfig 3616Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup. 3617The @code{-nodefconfig} option will prevent QEMU from loading any of those config files. 3618ETEXI 3619DEF("no-user-config", 0, QEMU_OPTION_nouserconfig, 3620 "-no-user-config\n" 3621 " do not load user-provided config files at startup\n", 3622 QEMU_ARCH_ALL) 3623STEXI 3624@item -no-user-config 3625@findex -no-user-config 3626The @code{-no-user-config} option makes QEMU not load any of the user-provided 3627config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config 3628files from @var{datadir}. 3629ETEXI 3630DEF("trace", HAS_ARG, QEMU_OPTION_trace, 3631 "-trace [[enable=]<pattern>][,events=<file>][,file=<file>]\n" 3632 " specify tracing options\n", 3633 QEMU_ARCH_ALL) 3634STEXI 3635HXCOMM This line is not accurate, as some sub-options are backend-specific but 3636HXCOMM HX does not support conditional compilation of text. 3637@item -trace [events=@var{file}][,file=@var{file}] 3638@findex -trace 3639 3640Specify tracing options. 3641 3642@table @option 3643@item [enable=]@var{pattern} 3644Immediately enable events matching @var{pattern}. 3645The file must contain one event name (as listed in the @file{trace-events} file) 3646per line; globbing patterns are accepted too. This option is only 3647available if QEMU has been compiled with the @var{simple}, @var{stderr} 3648or @var{ftrace} tracing backend. To specify multiple events or patterns, 3649specify the @option{-trace} option multiple times. 3650 3651Use @code{-trace help} to print a list of names of trace points. 3652 3653@item events=@var{file} 3654Immediately enable events listed in @var{file}. 3655The file must contain one event name (as listed in the @file{trace-events} file) 3656per line; globbing patterns are accepted too. This option is only 3657available if QEMU has been compiled with the @var{simple}, @var{stderr} or 3658@var{ftrace} tracing backend. 3659 3660@item file=@var{file} 3661Log output traces to @var{file}. 3662This option is only available if QEMU has been compiled with 3663the @var{simple} tracing backend. 3664@end table 3665ETEXI 3666 3667HXCOMM Internal use 3668DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL) 3669DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL) 3670 3671#ifdef __linux__ 3672DEF("enable-fips", 0, QEMU_OPTION_enablefips, 3673 "-enable-fips enable FIPS 140-2 compliance\n", 3674 QEMU_ARCH_ALL) 3675#endif 3676STEXI 3677@item -enable-fips 3678@findex -enable-fips 3679Enable FIPS 140-2 compliance mode. 3680ETEXI 3681 3682HXCOMM Deprecated by -machine accel=tcg property 3683DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386) 3684 3685HXCOMM Deprecated by kvm-pit driver properties 3686DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection, 3687 "", QEMU_ARCH_I386) 3688 3689HXCOMM Deprecated (ignored) 3690DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386) 3691 3692HXCOMM Deprecated by -machine kernel_irqchip=on|off property 3693DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386) 3694 3695HXCOMM Deprecated (ignored) 3696DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL) 3697 3698DEF("msg", HAS_ARG, QEMU_OPTION_msg, 3699 "-msg timestamp[=on|off]\n" 3700 " change the format of messages\n" 3701 " on|off controls leading timestamps (default:on)\n", 3702 QEMU_ARCH_ALL) 3703STEXI 3704@item -msg timestamp[=on|off] 3705@findex -msg 3706prepend a timestamp to each log message.(default:on) 3707ETEXI 3708 3709DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate, 3710 "-dump-vmstate <file>\n" 3711 " Output vmstate information in JSON format to file.\n" 3712 " Use the scripts/vmstate-static-checker.py file to\n" 3713 " check for possible regressions in migration code\n" 3714 " by comparing two such vmstate dumps.\n", 3715 QEMU_ARCH_ALL) 3716STEXI 3717@item -dump-vmstate @var{file} 3718@findex -dump-vmstate 3719Dump json-encoded vmstate information for current machine type to file 3720in @var{file} 3721ETEXI 3722 3723DEFHEADING(Generic object creation) 3724 3725DEF("object", HAS_ARG, QEMU_OPTION_object, 3726 "-object TYPENAME[,PROP1=VALUE1,...]\n" 3727 " create a new object of type TYPENAME setting properties\n" 3728 " in the order they are specified. Note that the 'id'\n" 3729 " property must be set. These objects are placed in the\n" 3730 " '/objects' path.\n", 3731 QEMU_ARCH_ALL) 3732STEXI 3733@item -object @var{typename}[,@var{prop1}=@var{value1},...] 3734@findex -object 3735Create a new object of type @var{typename} setting properties 3736in the order they are specified. Note that the 'id' 3737property must be set. These objects are placed in the 3738'/objects' path. 3739 3740@table @option 3741 3742@item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off} 3743 3744Creates a memory file backend object, which can be used to back 3745the guest RAM with huge pages. The @option{id} parameter is a 3746unique ID that will be used to reference this memory region 3747when configuring the @option{-numa} argument. The @option{size} 3748option provides the size of the memory region, and accepts 3749common suffixes, eg @option{500M}. The @option{mem-path} provides 3750the path to either a shared memory or huge page filesystem mount. 3751The @option{share} boolean option determines whether the memory 3752region is marked as private to QEMU, or shared. The latter allows 3753a co-operating external process to access the QEMU memory region. 3754 3755@item -object rng-random,id=@var{id},filename=@var{/dev/random} 3756 3757Creates a random number generator backend which obtains entropy from 3758a device on the host. The @option{id} parameter is a unique ID that 3759will be used to reference this entropy backend from the @option{virtio-rng} 3760device. The @option{filename} parameter specifies which file to obtain 3761entropy from and if omitted defaults to @option{/dev/random}. 3762 3763@item -object rng-egd,id=@var{id},chardev=@var{chardevid} 3764 3765Creates a random number generator backend which obtains entropy from 3766an external daemon running on the host. The @option{id} parameter is 3767a unique ID that will be used to reference this entropy backend from 3768the @option{virtio-rng} device. The @option{chardev} parameter is 3769the unique ID of a character device backend that provides the connection 3770to the RNG daemon. 3771 3772@item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off} 3773 3774Creates a TLS anonymous credentials object, which can be used to provide 3775TLS support on network backends. The @option{id} parameter is a unique 3776ID which network backends will use to access the credentials. The 3777@option{endpoint} is either @option{server} or @option{client} depending 3778on whether the QEMU network backend that uses the credentials will be 3779acting as a client or as a server. If @option{verify-peer} is enabled 3780(the default) then once the handshake is completed, the peer credentials 3781will be verified, though this is a no-op for anonymous credentials. 3782 3783The @var{dir} parameter tells QEMU where to find the credential 3784files. For server endpoints, this directory may contain a file 3785@var{dh-params.pem} providing diffie-hellman parameters to use 3786for the TLS server. If the file is missing, QEMU will generate 3787a set of DH parameters at startup. This is a computationally 3788expensive operation that consumes random pool entropy, so it is 3789recommended that a persistent set of parameters be generated 3790upfront and saved. 3791 3792@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} 3793 3794Creates a TLS anonymous credentials object, which can be used to provide 3795TLS support on network backends. The @option{id} parameter is a unique 3796ID which network backends will use to access the credentials. The 3797@option{endpoint} is either @option{server} or @option{client} depending 3798on whether the QEMU network backend that uses the credentials will be 3799acting as a client or as a server. If @option{verify-peer} is enabled 3800(the default) then once the handshake is completed, the peer credentials 3801will be verified. With x509 certificates, this implies that the clients 3802must be provided with valid client certificates too. 3803 3804The @var{dir} parameter tells QEMU where to find the credential 3805files. For server endpoints, this directory may contain a file 3806@var{dh-params.pem} providing diffie-hellman parameters to use 3807for the TLS server. If the file is missing, QEMU will generate 3808a set of DH parameters at startup. This is a computationally 3809expensive operation that consumes random pool entropy, so it is 3810recommended that a persistent set of parameters be generated 3811upfront and saved. 3812 3813For x509 certificate credentials the directory will contain further files 3814providing the x509 certificates. The certificates must be stored 3815in PEM format, in filenames @var{ca-cert.pem}, @var{ca-crl.pem} (optional), 3816@var{server-cert.pem} (only servers), @var{server-key.pem} (only servers), 3817@var{client-cert.pem} (only clients), and @var{client-key.pem} (only clients). 3818 3819For the @var{server-key.pem} and @var{client-key.pem} files which 3820contain sensitive private keys, it is possible to use an encrypted 3821version by providing the @var{passwordid} parameter. This provides 3822the ID of a previously created @code{secret} object containing the 3823password for decryption. 3824 3825@item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}] 3826 3827Interval @var{t} can't be 0, this filter batches the packet delivery: all 3828packets arriving in a given interval on netdev @var{netdevid} are delayed 3829until the end of the interval. Interval is in microseconds. 3830@option{status} is optional that indicate whether the netfilter is 3831on (enabled) or off (disabled), the default status for netfilter will be 'on'. 3832 3833queue @var{all|rx|tx} is an option that can be applied to any netfilter. 3834 3835@option{all}: the filter is attached both to the receive and the transmit 3836 queue of the netdev (default). 3837 3838@option{rx}: the filter is attached to the receive queue of the netdev, 3839 where it will receive packets sent to the netdev. 3840 3841@option{tx}: the filter is attached to the transmit queue of the netdev, 3842 where it will receive packets sent by the netdev. 3843 3844@item -object filter-dump,id=@var{id},netdev=@var{dev},file=@var{filename}][,maxlen=@var{len}] 3845 3846Dump the network traffic on netdev @var{dev} to the file specified by 3847@var{filename}. At most @var{len} bytes (64k by default) per packet are stored. 3848The file format is libpcap, so it can be analyzed with tools such as tcpdump 3849or Wireshark. 3850 3851@item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 3852@item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}] 3853 3854Defines a secret to store a password, encryption key, or some other sensitive 3855data. The sensitive data can either be passed directly via the @var{data} 3856parameter, or indirectly via the @var{file} parameter. Using the @var{data} 3857parameter is insecure unless the sensitive data is encrypted. 3858 3859The sensitive data can be provided in raw format (the default), or base64. 3860When encoded as JSON, the raw format only supports valid UTF-8 characters, 3861so base64 is recommended for sending binary data. QEMU will convert from 3862which ever format is provided to the format it needs internally. eg, an 3863RBD password can be provided in raw format, even though it will be base64 3864encoded when passed onto the RBD sever. 3865 3866For added protection, it is possible to encrypt the data associated with 3867a secret using the AES-256-CBC cipher. Use of encryption is indicated 3868by providing the @var{keyid} and @var{iv} parameters. The @var{keyid} 3869parameter provides the ID of a previously defined secret that contains 3870the AES-256 decryption key. This key should be 32-bytes long and be 3871base64 encoded. The @var{iv} parameter provides the random initialization 3872vector used for encryption of this particular secret and should be a 3873base64 encrypted string of the 32-byte IV. 3874 3875The simplest (insecure) usage is to provide the secret inline 3876 3877@example 3878 3879 # $QEMU -object secret,id=sec0,data=letmein,format=raw 3880 3881@end example 3882 3883The simplest secure usage is to provide the secret via a file 3884 3885 # echo -n "letmein" > mypasswd.txt 3886 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw 3887 3888For greater security, AES-256-CBC should be used. To illustrate usage, 3889consider the openssl command line tool which can encrypt the data. Note 3890that when encrypting, the plaintext must be padded to the cipher block 3891size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm. 3892 3893First a master key needs to be created in base64 encoding: 3894 3895@example 3896 # openssl rand -base64 32 > key.b64 3897 # KEY=$(base64 -d key.b64 | hexdump -v -e '/1 "%02X"') 3898@end example 3899 3900Each secret to be encrypted needs to have a random initialization vector 3901generated. These do not need to be kept secret 3902 3903@example 3904 # openssl rand -base64 16 > iv.b64 3905 # IV=$(base64 -d iv.b64 | hexdump -v -e '/1 "%02X"') 3906@end example 3907 3908The secret to be defined can now be encrypted, in this case we're 3909telling openssl to base64 encode the result, but it could be left 3910as raw bytes if desired. 3911 3912@example 3913 # SECRET=$(echo -n "letmein" | 3914 openssl enc -aes-256-cbc -a -K $KEY -iv $IV) 3915@end example 3916 3917When launching QEMU, create a master secret pointing to @code{key.b64} 3918and specify that to be used to decrypt the user password. Pass the 3919contents of @code{iv.b64} to the second secret 3920 3921@example 3922 # $QEMU \ 3923 -object secret,id=secmaster0,format=base64,file=key.b64 \ 3924 -object secret,id=sec0,keyid=secmaster0,format=base64,\ 3925 data=$SECRET,iv=$(<iv.b64) 3926@end example 3927 3928@end table 3929 3930ETEXI 3931 3932 3933HXCOMM This is the last statement. Insert new options before this line! 3934STEXI 3935@end table 3936ETEXI 3937
