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Diffstat (limited to 'qemu/qemu-options.hx')
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diff --git a/qemu/qemu-options.hx b/qemu/qemu-options.hx new file mode 100644 index 000000000..77f5853d5 --- /dev/null +++ b/qemu/qemu-options.hx @@ -0,0 +1,3579 @@ +HXCOMM Use DEFHEADING() to define headings in both help text and texi +HXCOMM Text between STEXI and ETEXI are copied to texi version and +HXCOMM discarded from C version +HXCOMM DEF(option, HAS_ARG/0, opt_enum, opt_help, arch_mask) is used to +HXCOMM construct option structures, enums and help message for specified +HXCOMM architectures. +HXCOMM HXCOMM can be used for comments, discarded from both texi and C + +DEFHEADING(Standard options:) +STEXI +@table @option +ETEXI + +DEF("help", 0, QEMU_OPTION_h, + "-h or -help display this help and exit\n", QEMU_ARCH_ALL) +STEXI +@item -h +@findex -h +Display help and exit +ETEXI + +DEF("version", 0, QEMU_OPTION_version, + "-version display version information and exit\n", QEMU_ARCH_ALL) +STEXI +@item -version +@findex -version +Display version information and exit +ETEXI + +DEF("machine", HAS_ARG, QEMU_OPTION_machine, \ + "-machine [type=]name[,prop[=value][,...]]\n" + " selects emulated machine ('-machine help' for list)\n" + " property accel=accel1[:accel2[:...]] selects accelerator\n" + " supported accelerators are kvm, xen, tcg (default: tcg)\n" + " kernel_irqchip=on|off controls accelerated irqchip support\n" + " vmport=on|off|auto controls emulation of vmport (default: auto)\n" + " kvm_shadow_mem=size of KVM shadow MMU\n" + " dump-guest-core=on|off include guest memory in a core dump (default=on)\n" + " mem-merge=on|off controls memory merge support (default: on)\n" + " iommu=on|off controls emulated Intel IOMMU (VT-d) support (default=off)\n" + " aes-key-wrap=on|off controls support for AES key wrapping (default=on)\n" + " dea-key-wrap=on|off controls support for DEA key wrapping (default=on)\n" + " suppress-vmdesc=on|off disables self-describing migration (default=off)\n", + QEMU_ARCH_ALL) +STEXI +@item -machine [type=]@var{name}[,prop=@var{value}[,...]] +@findex -machine +Select the emulated machine by @var{name}. Use @code{-machine help} to list +available machines. Supported machine properties are: +@table @option +@item accel=@var{accels1}[:@var{accels2}[:...]] +This is used to enable an accelerator. Depending on the target architecture, +kvm, xen, or tcg can be available. By default, tcg is used. If there is more +than one accelerator specified, the next one is used if the previous one fails +to initialize. +@item kernel_irqchip=on|off +Enables in-kernel irqchip support for the chosen accelerator when available. +@item vmport=on|off|auto +Enables emulation of VMWare IO port, for vmmouse etc. auto says to select the +value based on accel. For accel=xen the default is off otherwise the default +is on. +@item kvm_shadow_mem=size +Defines the size of the KVM shadow MMU. +@item dump-guest-core=on|off +Include guest memory in a core dump. The default is on. +@item mem-merge=on|off +Enables or disables memory merge support. This feature, when supported by +the host, de-duplicates identical memory pages among VMs instances +(enabled by default). +@item iommu=on|off +Enables or disables emulated Intel IOMMU (VT-d) support. The default is off. +@item aes-key-wrap=on|off +Enables or disables AES key wrapping support on s390-ccw hosts. This feature +controls whether AES wrapping keys will be created to allow +execution of AES cryptographic functions. The default is on. +@item dea-key-wrap=on|off +Enables or disables DEA key wrapping support on s390-ccw hosts. This feature +controls whether DEA wrapping keys will be created to allow +execution of DEA cryptographic functions. The default is on. +@end table +ETEXI + +HXCOMM Deprecated by -machine +DEF("M", HAS_ARG, QEMU_OPTION_M, "", QEMU_ARCH_ALL) + +DEF("cpu", HAS_ARG, QEMU_OPTION_cpu, + "-cpu cpu select CPU ('-cpu help' for list)\n", QEMU_ARCH_ALL) +STEXI +@item -cpu @var{model} +@findex -cpu +Select CPU model (@code{-cpu help} for list and additional feature selection) +ETEXI + +DEF("smp", HAS_ARG, QEMU_OPTION_smp, + "-smp [cpus=]n[,maxcpus=cpus][,cores=cores][,threads=threads][,sockets=sockets]\n" + " set the number of CPUs to 'n' [default=1]\n" + " maxcpus= maximum number of total cpus, including\n" + " offline CPUs for hotplug, etc\n" + " cores= number of CPU cores on one socket\n" + " threads= number of threads on one CPU core\n" + " sockets= number of discrete sockets in the system\n", + QEMU_ARCH_ALL) +STEXI +@item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}] +@findex -smp +Simulate an SMP system with @var{n} CPUs. On the PC target, up to 255 +CPUs are supported. On Sparc32 target, Linux limits the number of usable CPUs +to 4. +For the PC target, the number of @var{cores} per socket, the number +of @var{threads} per cores and the total number of @var{sockets} can be +specified. Missing values will be computed. If any on the three values is +given, the total number of CPUs @var{n} can be omitted. @var{maxcpus} +specifies the maximum number of hotpluggable CPUs. +ETEXI + +DEF("numa", HAS_ARG, QEMU_OPTION_numa, + "-numa node[,mem=size][,cpus=cpu[-cpu]][,nodeid=node]\n" + "-numa node[,memdev=id][,cpus=cpu[-cpu]][,nodeid=node]\n", QEMU_ARCH_ALL) +STEXI +@item -numa node[,mem=@var{size}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}] +@itemx -numa node[,memdev=@var{id}][,cpus=@var{cpu[-cpu]}][,nodeid=@var{node}] +@findex -numa +Simulate a multi node NUMA system. If @samp{mem}, @samp{memdev} +and @samp{cpus} are omitted, resources are split equally. Also, note +that the -@option{numa} option doesn't allocate any of the specified +resources. That is, it just assigns existing resources to NUMA nodes. This +means that one still has to use the @option{-m}, @option{-smp} options +to allocate RAM and VCPUs respectively, and possibly @option{-object} +to specify the memory backend for the @samp{memdev} suboption. + +@samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, if one +node uses @samp{memdev}, all of them have to use it. +ETEXI + +DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd, + "-add-fd fd=fd,set=set[,opaque=opaque]\n" + " Add 'fd' to fd 'set'\n", QEMU_ARCH_ALL) +STEXI +@item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}] +@findex -add-fd + +Add a file descriptor to an fd set. Valid options are: + +@table @option +@item fd=@var{fd} +This option defines the file descriptor of which a duplicate is added to fd set. +The file descriptor cannot be stdin, stdout, or stderr. +@item set=@var{set} +This option defines the ID of the fd set to add the file descriptor to. +@item opaque=@var{opaque} +This option defines a free-form string that can be used to describe @var{fd}. +@end table + +You can open an image using pre-opened file descriptors from an fd set: +@example +qemu-system-i386 +-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" +-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" +-drive file=/dev/fdset/2,index=0,media=disk +@end example +ETEXI + +DEF("set", HAS_ARG, QEMU_OPTION_set, + "-set group.id.arg=value\n" + " set <arg> parameter for item <id> of type <group>\n" + " i.e. -set drive.$id.file=/path/to/image\n", QEMU_ARCH_ALL) +STEXI +@item -set @var{group}.@var{id}.@var{arg}=@var{value} +@findex -set +Set parameter @var{arg} for item @var{id} of type @var{group}\n" +ETEXI + +DEF("global", HAS_ARG, QEMU_OPTION_global, + "-global driver.property=value\n" + "-global driver=driver,property=property,value=value\n" + " set a global default for a driver property\n", + QEMU_ARCH_ALL) +STEXI +@item -global @var{driver}.@var{prop}=@var{value} +@itemx -global driver=@var{driver},property=@var{property},value=@var{value} +@findex -global +Set default value of @var{driver}'s property @var{prop} to @var{value}, e.g.: + +@example +qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk +@end example + +In particular, you can use this to set driver properties for devices which are +created automatically by the machine model. To create a device which is not +created automatically and set properties on it, use -@option{device}. + +-global @var{driver}.@var{prop}=@var{value} is shorthand for -global +driver=@var{driver},property=@var{prop},value=@var{value}. The +longhand syntax works even when @var{driver} contains a dot. +ETEXI + +DEF("boot", HAS_ARG, QEMU_OPTION_boot, + "-boot [order=drives][,once=drives][,menu=on|off]\n" + " [,splash=sp_name][,splash-time=sp_time][,reboot-timeout=rb_time][,strict=on|off]\n" + " 'drives': floppy (a), hard disk (c), CD-ROM (d), network (n)\n" + " 'sp_name': the file's name that would be passed to bios as logo picture, if menu=on\n" + " 'sp_time': the period that splash picture last if menu=on, unit is ms\n" + " 'rb_timeout': the timeout before guest reboot when boot failed, unit is ms\n", + QEMU_ARCH_ALL) +STEXI +@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] +@findex -boot +Specify boot order @var{drives} as a string of drive letters. Valid +drive letters depend on the target architecture. The x86 PC uses: a, b +(floppy 1 and 2), c (first hard disk), d (first CD-ROM), n-p (Etherboot +from network adapter 1-4), hard disk boot is the default. To apply a +particular boot order only on the first startup, specify it via +@option{once}. + +Interactive boot menus/prompts can be enabled via @option{menu=on} as far +as firmware/BIOS supports them. The default is non-interactive boot. + +A splash picture could be passed to bios, enabling user to show it as logo, +when option splash=@var{sp_name} is given and menu=on, If firmware/BIOS +supports them. Currently Seabios for X86 system support it. +limitation: The splash file could be a jpeg file or a BMP file in 24 BPP +format(true color). The resolution should be supported by the SVGA mode, so +the recommended is 320x240, 640x480, 800x640. + +A timeout could be passed to bios, guest will pause for @var{rb_timeout} ms +when boot failed, then reboot. If @var{rb_timeout} is '-1', guest will not +reboot, qemu passes '-1' to bios by default. Currently Seabios for X86 +system support it. + +Do strict boot via @option{strict=on} as far as firmware/BIOS +supports it. This only effects when boot priority is changed by +bootindex options. The default is non-strict boot. + +@example +# try to boot from network first, then from hard disk +qemu-system-i386 -boot order=nc +# boot from CD-ROM first, switch back to default order after reboot +qemu-system-i386 -boot once=d +# boot with a splash picture for 5 seconds. +qemu-system-i386 -boot menu=on,splash=/root/boot.bmp,splash-time=5000 +@end example + +Note: The legacy format '-boot @var{drives}' is still supported but its +use is discouraged as it may be removed from future versions. +ETEXI + +DEF("m", HAS_ARG, QEMU_OPTION_m, + "-m[emory] [size=]megs[,slots=n,maxmem=size]\n" + " configure guest RAM\n" + " size: initial amount of guest memory\n" + " slots: number of hotplug slots (default: none)\n" + " maxmem: maximum amount of guest memory (default: none)\n" + "NOTE: Some architectures might enforce a specific granularity\n", + QEMU_ARCH_ALL) +STEXI +@item -m [size=]@var{megs}[,slots=n,maxmem=size] +@findex -m +Sets guest startup RAM size to @var{megs} megabytes. Default is 128 MiB. +Optionally, a suffix of ``M'' or ``G'' can be used to signify a value in +megabytes or gigabytes respectively. Optional pair @var{slots}, @var{maxmem} +could be used to set amount of hotpluggable memory slots and maximum amount of +memory. Note that @var{maxmem} must be aligned to the page size. + +For example, the following command-line sets the guest startup RAM size to +1GB, creates 3 slots to hotplug additional memory and sets the maximum +memory the guest can reach to 4GB: + +@example +qemu-system-x86_64 -m 1G,slots=3,maxmem=4G +@end example + +If @var{slots} and @var{maxmem} are not specified, memory hotplug won't +be enabled and the guest startup RAM will never increase. +ETEXI + +DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath, + "-mem-path FILE provide backing storage for guest RAM\n", QEMU_ARCH_ALL) +STEXI +@item -mem-path @var{path} +@findex -mem-path +Allocate guest RAM from a temporarily created file in @var{path}. +ETEXI + +DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc, + "-mem-prealloc preallocate guest memory (use with -mem-path)\n", + QEMU_ARCH_ALL) +STEXI +@item -mem-prealloc +@findex -mem-prealloc +Preallocate memory when using -mem-path. +ETEXI + +DEF("k", HAS_ARG, QEMU_OPTION_k, + "-k language use keyboard layout (for example 'fr' for French)\n", + QEMU_ARCH_ALL) +STEXI +@item -k @var{language} +@findex -k +Use keyboard layout @var{language} (for example @code{fr} for +French). This option is only needed where it is not easy to get raw PC +keycodes (e.g. on Macs, with some X11 servers or with a VNC +display). You don't normally need to use it on PC/Linux or PC/Windows +hosts. + +The available layouts are: +@example +ar de-ch es fo fr-ca hu ja mk no pt-br sv +da en-gb et fr fr-ch is lt nl pl ru th +de en-us fi fr-be hr it lv nl-be pt sl tr +@end example + +The default is @code{en-us}. +ETEXI + + +DEF("audio-help", 0, QEMU_OPTION_audio_help, + "-audio-help print list of audio drivers and their options\n", + QEMU_ARCH_ALL) +STEXI +@item -audio-help +@findex -audio-help +Will show the audio subsystem help: list of drivers, tunable +parameters. +ETEXI + +DEF("soundhw", HAS_ARG, QEMU_OPTION_soundhw, + "-soundhw c1,... enable audio support\n" + " and only specified sound cards (comma separated list)\n" + " use '-soundhw help' to get the list of supported cards\n" + " use '-soundhw all' to enable all of them\n", QEMU_ARCH_ALL) +STEXI +@item -soundhw @var{card1}[,@var{card2},...] or -soundhw all +@findex -soundhw +Enable audio and selected sound hardware. Use 'help' to print all +available sound hardware. + +@example +qemu-system-i386 -soundhw sb16,adlib disk.img +qemu-system-i386 -soundhw es1370 disk.img +qemu-system-i386 -soundhw ac97 disk.img +qemu-system-i386 -soundhw hda disk.img +qemu-system-i386 -soundhw all disk.img +qemu-system-i386 -soundhw help +@end example + +Note that Linux's i810_audio OSS kernel (for AC97) module might +require manually specifying clocking. + +@example +modprobe i810_audio clocking=48000 +@end example +ETEXI + +DEF("balloon", HAS_ARG, QEMU_OPTION_balloon, + "-balloon none disable balloon device\n" + "-balloon virtio[,addr=str]\n" + " enable virtio balloon device (default)\n", QEMU_ARCH_ALL) +STEXI +@item -balloon none +@findex -balloon +Disable balloon device. +@item -balloon virtio[,addr=@var{addr}] +Enable virtio balloon device (default), optionally with PCI address +@var{addr}. +ETEXI + +DEF("device", HAS_ARG, QEMU_OPTION_device, + "-device driver[,prop[=value][,...]]\n" + " add device (based on driver)\n" + " prop=value,... sets driver properties\n" + " use '-device help' to print all possible drivers\n" + " use '-device driver,help' to print all possible properties\n", + QEMU_ARCH_ALL) +STEXI +@item -device @var{driver}[,@var{prop}[=@var{value}][,...]] +@findex -device +Add device @var{driver}. @var{prop}=@var{value} sets driver +properties. Valid properties depend on the driver. To get help on +possible drivers and properties, use @code{-device help} and +@code{-device @var{driver},help}. +ETEXI + +DEF("name", HAS_ARG, QEMU_OPTION_name, + "-name string1[,process=string2][,debug-threads=on|off]\n" + " set the name of the guest\n" + " string1 sets the window title and string2 the process name (on Linux)\n" + " When debug-threads is enabled, individual threads are given a separate name (on Linux)\n" + " NOTE: The thread names are for debugging and not a stable API.\n", + QEMU_ARCH_ALL) +STEXI +@item -name @var{name} +@findex -name +Sets the @var{name} of the guest. +This name will be displayed in the SDL window caption. +The @var{name} will also be used for the VNC server. +Also optionally set the top visible process name in Linux. +Naming of individual threads can also be enabled on Linux to aid debugging. +ETEXI + +DEF("uuid", HAS_ARG, QEMU_OPTION_uuid, + "-uuid %08x-%04x-%04x-%04x-%012x\n" + " specify machine UUID\n", QEMU_ARCH_ALL) +STEXI +@item -uuid @var{uuid} +@findex -uuid +Set system UUID. +ETEXI + +STEXI +@end table +ETEXI +DEFHEADING() + +DEFHEADING(Block device options:) +STEXI +@table @option +ETEXI + +DEF("fda", HAS_ARG, QEMU_OPTION_fda, + "-fda/-fdb file use 'file' as floppy disk 0/1 image\n", QEMU_ARCH_ALL) +DEF("fdb", HAS_ARG, QEMU_OPTION_fdb, "", QEMU_ARCH_ALL) +STEXI +@item -fda @var{file} +@itemx -fdb @var{file} +@findex -fda +@findex -fdb +Use @var{file} as floppy disk 0/1 image (@pxref{disk_images}). +ETEXI + +DEF("hda", HAS_ARG, QEMU_OPTION_hda, + "-hda/-hdb file use 'file' as IDE hard disk 0/1 image\n", QEMU_ARCH_ALL) +DEF("hdb", HAS_ARG, QEMU_OPTION_hdb, "", QEMU_ARCH_ALL) +DEF("hdc", HAS_ARG, QEMU_OPTION_hdc, + "-hdc/-hdd file use 'file' as IDE hard disk 2/3 image\n", QEMU_ARCH_ALL) +DEF("hdd", HAS_ARG, QEMU_OPTION_hdd, "", QEMU_ARCH_ALL) +STEXI +@item -hda @var{file} +@itemx -hdb @var{file} +@itemx -hdc @var{file} +@itemx -hdd @var{file} +@findex -hda +@findex -hdb +@findex -hdc +@findex -hdd +Use @var{file} as hard disk 0, 1, 2 or 3 image (@pxref{disk_images}). +ETEXI + +DEF("cdrom", HAS_ARG, QEMU_OPTION_cdrom, + "-cdrom file use 'file' as IDE cdrom image (cdrom is ide1 master)\n", + QEMU_ARCH_ALL) +STEXI +@item -cdrom @var{file} +@findex -cdrom +Use @var{file} as CD-ROM image (you cannot use @option{-hdc} and +@option{-cdrom} at the same time). You can use the host CD-ROM by +using @file{/dev/cdrom} as filename (@pxref{host_drives}). +ETEXI + +DEF("drive", HAS_ARG, QEMU_OPTION_drive, + "-drive [file=file][,if=type][,bus=n][,unit=m][,media=d][,index=i]\n" + " [,cyls=c,heads=h,secs=s[,trans=t]][,snapshot=on|off]\n" + " [,cache=writethrough|writeback|none|directsync|unsafe][,format=f]\n" + " [,serial=s][,addr=A][,rerror=ignore|stop|report]\n" + " [,werror=ignore|stop|report|enospc][,id=name][,aio=threads|native]\n" + " [,readonly=on|off][,copy-on-read=on|off]\n" + " [,discard=ignore|unmap][,detect-zeroes=on|off|unmap]\n" + " [[,bps=b]|[[,bps_rd=r][,bps_wr=w]]]\n" + " [[,iops=i]|[[,iops_rd=r][,iops_wr=w]]]\n" + " [[,bps_max=bm]|[[,bps_rd_max=rm][,bps_wr_max=wm]]]\n" + " [[,iops_max=im]|[[,iops_rd_max=irm][,iops_wr_max=iwm]]]\n" + " [[,iops_size=is]]\n" + " [[,group=g]]\n" + " use 'file' as a drive image\n", QEMU_ARCH_ALL) +STEXI +@item -drive @var{option}[,@var{option}[,@var{option}[,...]]] +@findex -drive + +Define a new drive. Valid options are: + +@table @option +@item file=@var{file} +This option defines which disk image (@pxref{disk_images}) to use with +this drive. If the filename contains comma, you must double it +(for instance, "file=my,,file" to use file "my,file"). + +Special files such as iSCSI devices can be specified using protocol +specific URLs. See the section for "Device URL Syntax" for more information. +@item if=@var{interface} +This option defines on which type on interface the drive is connected. +Available types are: ide, scsi, sd, mtd, floppy, pflash, virtio. +@item bus=@var{bus},unit=@var{unit} +These options define where is connected the drive by defining the bus number and +the unit id. +@item index=@var{index} +This option defines where is connected the drive by using an index in the list +of available connectors of a given interface type. +@item media=@var{media} +This option defines the type of the media: disk or cdrom. +@item cyls=@var{c},heads=@var{h},secs=@var{s}[,trans=@var{t}] +These options have the same definition as they have in @option{-hdachs}. +@item snapshot=@var{snapshot} +@var{snapshot} is "on" or "off" and controls snapshot mode for the given drive +(see @option{-snapshot}). +@item cache=@var{cache} +@var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data. +@item aio=@var{aio} +@var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO. +@item discard=@var{discard} +@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. +@item format=@var{format} +Specify which disk @var{format} will be used rather than detecting +the format. Can be used to specifiy format=raw to avoid interpreting +an untrusted format header. +@item serial=@var{serial} +This option specifies the serial number to assign to the device. +@item addr=@var{addr} +Specify the controller's PCI address (if=virtio only). +@item werror=@var{action},rerror=@var{action} +Specify which @var{action} to take on write and read errors. Valid actions are: +"ignore" (ignore the error and try to continue), "stop" (pause QEMU), +"report" (report the error to the guest), "enospc" (pause QEMU only if the +host disk is full; report the error to the guest otherwise). +The default setting is @option{werror=enospc} and @option{rerror=report}. +@item readonly +Open drive @option{file} as read-only. Guest write attempts will fail. +@item copy-on-read=@var{copy-on-read} +@var{copy-on-read} is "on" or "off" and enables whether to copy read backing +file sectors into the image file. +@item detect-zeroes=@var{detect-zeroes} +@var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic +conversion of plain zero writes by the OS to driver specific optimized +zero write commands. You may even choose "unmap" if @var{discard} is set +to "unmap" to allow a zero write to be converted to an UNMAP operation. +@end table + +By default, the @option{cache=writeback} mode is used. It will report data +writes as completed as soon as the data is present in the host page cache. +This is safe as long as your guest OS makes sure to correctly flush disk caches +where needed. If your guest OS does not handle volatile disk write caches +correctly and your host crashes or loses power, then the guest may experience +data corruption. + +For such guests, you should consider using @option{cache=writethrough}. This +means that the host page cache will be used to read and write data, but write +notification will be sent to the guest only after QEMU has made sure to flush +each write to the disk. Be aware that this has a major impact on performance. + +The host page cache can be avoided entirely with @option{cache=none}. This will +attempt to do disk IO directly to the guest's memory. QEMU may still perform +an internal copy of the data. Note that this is considered a writeback mode and +the guest OS must handle the disk write cache correctly in order to avoid data +corruption on host crashes. + +The host page cache can be avoided while only sending write notifications to +the guest when the data has been flushed to the disk using +@option{cache=directsync}. + +In case you don't care about data integrity over host failures, use +@option{cache=unsafe}. This option tells QEMU that it never needs to write any +data to the disk but can instead keep things in cache. If anything goes wrong, +like your host losing power, the disk storage getting disconnected accidentally, +etc. your image will most probably be rendered unusable. When using +the @option{-snapshot} option, unsafe caching is always used. + +Copy-on-read avoids accessing the same backing file sectors repeatedly and is +useful when the backing file is over a slow network. By default copy-on-read +is off. + +Instead of @option{-cdrom} you can use: +@example +qemu-system-i386 -drive file=file,index=2,media=cdrom +@end example + +Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can +use: +@example +qemu-system-i386 -drive file=file,index=0,media=disk +qemu-system-i386 -drive file=file,index=1,media=disk +qemu-system-i386 -drive file=file,index=2,media=disk +qemu-system-i386 -drive file=file,index=3,media=disk +@end example + +You can open an image using pre-opened file descriptors from an fd set: +@example +qemu-system-i386 +-add-fd fd=3,set=2,opaque="rdwr:/path/to/file" +-add-fd fd=4,set=2,opaque="rdonly:/path/to/file" +-drive file=/dev/fdset/2,index=0,media=disk +@end example + +You can connect a CDROM to the slave of ide0: +@example +qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom +@end example + +If you don't specify the "file=" argument, you define an empty drive: +@example +qemu-system-i386 -drive if=ide,index=1,media=cdrom +@end example + +You can connect a SCSI disk with unit ID 6 on the bus #0: +@example +qemu-system-i386 -drive file=file,if=scsi,bus=0,unit=6 +@end example + +Instead of @option{-fda}, @option{-fdb}, you can use: +@example +qemu-system-i386 -drive file=file,index=0,if=floppy +qemu-system-i386 -drive file=file,index=1,if=floppy +@end example + +By default, @var{interface} is "ide" and @var{index} is automatically +incremented: +@example +qemu-system-i386 -drive file=a -drive file=b" +@end example +is interpreted like: +@example +qemu-system-i386 -hda a -hdb b +@end example +ETEXI + +DEF("mtdblock", HAS_ARG, QEMU_OPTION_mtdblock, + "-mtdblock file use 'file' as on-board Flash memory image\n", + QEMU_ARCH_ALL) +STEXI +@item -mtdblock @var{file} +@findex -mtdblock +Use @var{file} as on-board Flash memory image. +ETEXI + +DEF("sd", HAS_ARG, QEMU_OPTION_sd, + "-sd file use 'file' as SecureDigital card image\n", QEMU_ARCH_ALL) +STEXI +@item -sd @var{file} +@findex -sd +Use @var{file} as SecureDigital card image. +ETEXI + +DEF("pflash", HAS_ARG, QEMU_OPTION_pflash, + "-pflash file use 'file' as a parallel flash image\n", QEMU_ARCH_ALL) +STEXI +@item -pflash @var{file} +@findex -pflash +Use @var{file} as a parallel flash image. +ETEXI + +DEF("snapshot", 0, QEMU_OPTION_snapshot, + "-snapshot write to temporary files instead of disk image files\n", + QEMU_ARCH_ALL) +STEXI +@item -snapshot +@findex -snapshot +Write to temporary files instead of disk image files. In this case, +the raw disk image you use is not written back. You can however force +the write back by pressing @key{C-a s} (@pxref{disk_images}). +ETEXI + +DEF("hdachs", HAS_ARG, QEMU_OPTION_hdachs, \ + "-hdachs c,h,s[,t]\n" \ + " force hard disk 0 physical geometry and the optional BIOS\n" \ + " translation (t=none or lba) (usually QEMU can guess them)\n", + QEMU_ARCH_ALL) +STEXI +@item -hdachs @var{c},@var{h},@var{s},[,@var{t}] +@findex -hdachs +Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <= +@var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS +translation mode (@var{t}=none, lba or auto). Usually QEMU can guess +all those parameters. This option is useful for old MS-DOS disk +images. +ETEXI + +DEF("fsdev", HAS_ARG, QEMU_OPTION_fsdev, + "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n" + " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n", + QEMU_ARCH_ALL) + +STEXI + +@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}] +@findex -fsdev +Define a new file system device. Valid options are: +@table @option +@item @var{fsdriver} +This option specifies the fs driver backend to use. +Currently "local", "handle" and "proxy" file system drivers are supported. +@item id=@var{id} +Specifies identifier for this device +@item path=@var{path} +Specifies the export path for the file system device. Files under +this path will be available to the 9p client on the guest. +@item security_model=@var{security_model} +Specifies the security model to be used for this export path. +Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". +In "passthrough" security model, files are stored using the same +credentials as they are created on the guest. This requires QEMU +to run as root. In "mapped-xattr" security model, some of the file +attributes like uid, gid, mode bits and link target are stored as +file attributes. For "mapped-file" these attributes are stored in the +hidden .virtfs_metadata directory. Directories exported by this security model cannot +interact with other unix tools. "none" security model is same as +passthrough except the sever won't report failures if it fails to +set file attributes like ownership. Security model is mandatory +only for local fsdriver. Other fsdrivers (like handle, proxy) don't take +security model as a parameter. +@item writeout=@var{writeout} +This is an optional argument. The only supported value is "immediate". +This means that host page cache will be used to read and write data but +write notification will be sent to the guest only when the data has been +reported as written by the storage subsystem. +@item readonly +Enables exporting 9p share as a readonly mount for guests. By default +read-write access is given. +@item socket=@var{socket} +Enables proxy filesystem driver to use passed socket file for communicating +with virtfs-proxy-helper +@item sock_fd=@var{sock_fd} +Enables proxy filesystem driver to use passed socket descriptor for +communicating with virtfs-proxy-helper. Usually a helper like libvirt +will create socketpair and pass one of the fds as sock_fd +@end table + +-fsdev option is used along with -device driver "virtio-9p-pci". +@item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag} +Options for virtio-9p-pci driver are: +@table @option +@item fsdev=@var{id} +Specifies the id value specified along with -fsdev option +@item mount_tag=@var{mount_tag} +Specifies the tag name to be used by the guest to mount this export point +@end table + +ETEXI + +DEF("virtfs", HAS_ARG, QEMU_OPTION_virtfs, + "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n" + " [,writeout=immediate][,readonly][,socket=socket|sock_fd=sock_fd]\n", + QEMU_ARCH_ALL) + +STEXI + +@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}] +@findex -virtfs + +The general form of a Virtual File system pass-through options are: +@table @option +@item @var{fsdriver} +This option specifies the fs driver backend to use. +Currently "local", "handle" and "proxy" file system drivers are supported. +@item id=@var{id} +Specifies identifier for this device +@item path=@var{path} +Specifies the export path for the file system device. Files under +this path will be available to the 9p client on the guest. +@item security_model=@var{security_model} +Specifies the security model to be used for this export path. +Supported security models are "passthrough", "mapped-xattr", "mapped-file" and "none". +In "passthrough" security model, files are stored using the same +credentials as they are created on the guest. This requires QEMU +to run as root. In "mapped-xattr" security model, some of the file +attributes like uid, gid, mode bits and link target are stored as +file attributes. For "mapped-file" these attributes are stored in the +hidden .virtfs_metadata directory. Directories exported by this security model cannot +interact with other unix tools. "none" security model is same as +passthrough except the sever won't report failures if it fails to +set file attributes like ownership. Security model is mandatory only +for local fsdriver. Other fsdrivers (like handle, proxy) don't take security +model as a parameter. +@item writeout=@var{writeout} +This is an optional argument. The only supported value is "immediate". +This means that host page cache will be used to read and write data but +write notification will be sent to the guest only when the data has been +reported as written by the storage subsystem. +@item readonly +Enables exporting 9p share as a readonly mount for guests. By default +read-write access is given. +@item socket=@var{socket} +Enables proxy filesystem driver to use passed socket file for +communicating with virtfs-proxy-helper. Usually a helper like libvirt +will create socketpair and pass one of the fds as sock_fd +@item sock_fd +Enables proxy filesystem driver to use passed 'sock_fd' as the socket +descriptor for interfacing with virtfs-proxy-helper +@end table +ETEXI + +DEF("virtfs_synth", 0, QEMU_OPTION_virtfs_synth, + "-virtfs_synth Create synthetic file system image\n", + QEMU_ARCH_ALL) +STEXI +@item -virtfs_synth +@findex -virtfs_synth +Create synthetic file system image +ETEXI + +STEXI +@end table +ETEXI +DEFHEADING() + +DEFHEADING(USB options:) +STEXI +@table @option +ETEXI + +DEF("usb", 0, QEMU_OPTION_usb, + "-usb enable the USB driver (will be the default soon)\n", + QEMU_ARCH_ALL) +STEXI +@item -usb +@findex -usb +Enable the USB driver (will be the default soon) +ETEXI + +DEF("usbdevice", HAS_ARG, QEMU_OPTION_usbdevice, + "-usbdevice name add the host or guest USB device 'name'\n", + QEMU_ARCH_ALL) +STEXI + +@item -usbdevice @var{devname} +@findex -usbdevice +Add the USB device @var{devname}. @xref{usb_devices}. + +@table @option + +@item mouse +Virtual Mouse. This will override the PS/2 mouse emulation when activated. + +@item tablet +Pointer device that uses absolute coordinates (like a touchscreen). This +means QEMU is able to report the mouse position without having to grab the +mouse. Also overrides the PS/2 mouse emulation when activated. + +@item disk:[format=@var{format}]:@var{file} +Mass storage device based on file. The optional @var{format} argument +will be used rather than detecting the format. Can be used to specifiy +@code{format=raw} to avoid interpreting an untrusted format header. + +@item host:@var{bus}.@var{addr} +Pass through the host device identified by @var{bus}.@var{addr} (Linux only). + +@item host:@var{vendor_id}:@var{product_id} +Pass through the host device identified by @var{vendor_id}:@var{product_id} +(Linux only). + +@item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev} +Serial converter to host character device @var{dev}, see @code{-serial} for the +available devices. + +@item braille +Braille device. This will use BrlAPI to display the braille output on a real +or fake device. + +@item net:@var{options} +Network adapter that supports CDC ethernet and RNDIS protocols. + +@end table +ETEXI + +STEXI +@end table +ETEXI +DEFHEADING() + +DEFHEADING(Display options:) +STEXI +@table @option +ETEXI + +DEF("display", HAS_ARG, QEMU_OPTION_display, + "-display sdl[,frame=on|off][,alt_grab=on|off][,ctrl_grab=on|off]\n" + " [,window_close=on|off]|curses|none|\n" + " gtk[,grab_on_hover=on|off]|\n" + " vnc=<display>[,<optargs>]\n" + " select display type\n", QEMU_ARCH_ALL) +STEXI +@item -display @var{type} +@findex -display +Select type of display to use. This option is a replacement for the +old style -sdl/-curses/... options. Valid values for @var{type} are +@table @option +@item sdl +Display video output via SDL (usually in a separate graphics +window; see the SDL documentation for other possibilities). +@item curses +Display video output via curses. For graphics device models which +support a text mode, QEMU can display this output using a +curses/ncurses interface. Nothing is displayed when the graphics +device is in graphical mode or if the graphics device does not support +a text mode. Generally only the VGA device models support text mode. +@item none +Do not display video output. The guest will still see an emulated +graphics card, but its output will not be displayed to the QEMU +user. This option differs from the -nographic option in that it +only affects what is done with video output; -nographic also changes +the destination of the serial and parallel port data. +@item gtk +Display video output in a GTK window. This interface provides drop-down +menus and other UI elements to configure and control the VM during +runtime. +@item vnc +Start a VNC server on display <arg> +@end table +ETEXI + +DEF("nographic", 0, QEMU_OPTION_nographic, + "-nographic disable graphical output and redirect serial I/Os to console\n", + QEMU_ARCH_ALL) +STEXI +@item -nographic +@findex -nographic +Normally, QEMU uses SDL to display the VGA output. With this option, +you can totally disable graphical output so that QEMU is a simple +command line application. The emulated serial port is redirected on +the console and muxed with the monitor (unless redirected elsewhere +explicitly). Therefore, you can still use QEMU to debug a Linux kernel +with a serial console. Use @key{C-a h} for help on switching between +the console and monitor. +ETEXI + +DEF("curses", 0, QEMU_OPTION_curses, + "-curses use a curses/ncurses interface instead of SDL\n", + QEMU_ARCH_ALL) +STEXI +@item -curses +@findex -curses +Normally, QEMU uses SDL to display the VGA output. With this option, +QEMU can display the VGA output when in text mode using a +curses/ncurses interface. Nothing is displayed in graphical mode. +ETEXI + +DEF("no-frame", 0, QEMU_OPTION_no_frame, + "-no-frame open SDL window without a frame and window decorations\n", + QEMU_ARCH_ALL) +STEXI +@item -no-frame +@findex -no-frame +Do not use decorations for SDL windows and start them using the whole +available screen space. This makes the using QEMU in a dedicated desktop +workspace more convenient. +ETEXI + +DEF("alt-grab", 0, QEMU_OPTION_alt_grab, + "-alt-grab use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt)\n", + QEMU_ARCH_ALL) +STEXI +@item -alt-grab +@findex -alt-grab +Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also +affects the special keys (for fullscreen, monitor-mode switching, etc). +ETEXI + +DEF("ctrl-grab", 0, QEMU_OPTION_ctrl_grab, + "-ctrl-grab use Right-Ctrl to grab mouse (instead of Ctrl-Alt)\n", + QEMU_ARCH_ALL) +STEXI +@item -ctrl-grab +@findex -ctrl-grab +Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also +affects the special keys (for fullscreen, monitor-mode switching, etc). +ETEXI + +DEF("no-quit", 0, QEMU_OPTION_no_quit, + "-no-quit disable SDL window close capability\n", QEMU_ARCH_ALL) +STEXI +@item -no-quit +@findex -no-quit +Disable SDL window close capability. +ETEXI + +DEF("sdl", 0, QEMU_OPTION_sdl, + "-sdl enable SDL\n", QEMU_ARCH_ALL) +STEXI +@item -sdl +@findex -sdl +Enable SDL. +ETEXI + +DEF("spice", HAS_ARG, QEMU_OPTION_spice, + "-spice [port=port][,tls-port=secured-port][,x509-dir=<dir>]\n" + " [,x509-key-file=<file>][,x509-key-password=<file>]\n" + " [,x509-cert-file=<file>][,x509-cacert-file=<file>]\n" + " [,x509-dh-key-file=<file>][,addr=addr][,ipv4|ipv6|unix]\n" + " [,tls-ciphers=<list>]\n" + " [,tls-channel=[main|display|cursor|inputs|record|playback]]\n" + " [,plaintext-channel=[main|display|cursor|inputs|record|playback]]\n" + " [,sasl][,password=<secret>][,disable-ticketing]\n" + " [,image-compression=[auto_glz|auto_lz|quic|glz|lz|off]]\n" + " [,jpeg-wan-compression=[auto|never|always]]\n" + " [,zlib-glz-wan-compression=[auto|never|always]]\n" + " [,streaming-video=[off|all|filter]][,disable-copy-paste]\n" + " [,disable-agent-file-xfer][,agent-mouse=[on|off]]\n" + " [,playback-compression=[on|off]][,seamless-migration=[on|off]]\n" + " enable spice\n" + " at least one of {port, tls-port} is mandatory\n", + QEMU_ARCH_ALL) +STEXI +@item -spice @var{option}[,@var{option}[,...]] +@findex -spice +Enable the spice remote desktop protocol. Valid options are + +@table @option + +@item port=<nr> +Set the TCP port spice is listening on for plaintext channels. + +@item addr=<addr> +Set the IP address spice is listening on. Default is any address. + +@item ipv4 +@itemx ipv6 +@itemx unix +Force using the specified IP version. + +@item password=<secret> +Set the password you need to authenticate. + +@item sasl +Require that the client use SASL to authenticate with the spice. +The exact choice of authentication method used is controlled from the +system / user's SASL configuration file for the 'qemu' service. This +is typically found in /etc/sasl2/qemu.conf. If running QEMU as an +unprivileged user, an environment variable SASL_CONF_PATH can be used +to make it search alternate locations for the service config. +While some SASL auth methods can also provide data encryption (eg GSSAPI), +it is recommended that SASL always be combined with the 'tls' and +'x509' settings to enable use of SSL and server certificates. This +ensures a data encryption preventing compromise of authentication +credentials. + +@item disable-ticketing +Allow client connects without authentication. + +@item disable-copy-paste +Disable copy paste between the client and the guest. + +@item disable-agent-file-xfer +Disable spice-vdagent based file-xfer between the client and the guest. + +@item tls-port=<nr> +Set the TCP port spice is listening on for encrypted channels. + +@item x509-dir=<dir> +Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir + +@item x509-key-file=<file> +@itemx x509-key-password=<file> +@itemx x509-cert-file=<file> +@itemx x509-cacert-file=<file> +@itemx x509-dh-key-file=<file> +The x509 file names can also be configured individually. + +@item tls-ciphers=<list> +Specify which ciphers to use. + +@item tls-channel=[main|display|cursor|inputs|record|playback] +@itemx plaintext-channel=[main|display|cursor|inputs|record|playback] +Force specific channel to be used with or without TLS encryption. The +options can be specified multiple times to configure multiple +channels. The special name "default" can be used to set the default +mode. For channels which are not explicitly forced into one mode the +spice client is allowed to pick tls/plaintext as he pleases. + +@item image-compression=[auto_glz|auto_lz|quic|glz|lz|off] +Configure image compression (lossless). +Default is auto_glz. + +@item jpeg-wan-compression=[auto|never|always] +@itemx zlib-glz-wan-compression=[auto|never|always] +Configure wan image compression (lossy for slow links). +Default is auto. + +@item streaming-video=[off|all|filter] +Configure video stream detection. Default is filter. + +@item agent-mouse=[on|off] +Enable/disable passing mouse events via vdagent. Default is on. + +@item playback-compression=[on|off] +Enable/disable audio stream compression (using celt 0.5.1). Default is on. + +@item seamless-migration=[on|off] +Enable/disable spice seamless migration. Default is off. + +@end table +ETEXI + +DEF("portrait", 0, QEMU_OPTION_portrait, + "-portrait rotate graphical output 90 deg left (only PXA LCD)\n", + QEMU_ARCH_ALL) +STEXI +@item -portrait +@findex -portrait +Rotate graphical output 90 deg left (only PXA LCD). +ETEXI + +DEF("rotate", HAS_ARG, QEMU_OPTION_rotate, + "-rotate <deg> rotate graphical output some deg left (only PXA LCD)\n", + QEMU_ARCH_ALL) +STEXI +@item -rotate @var{deg} +@findex -rotate +Rotate graphical output some deg left (only PXA LCD). +ETEXI + +DEF("vga", HAS_ARG, QEMU_OPTION_vga, + "-vga [std|cirrus|vmware|qxl|xenfb|tcx|cg3|virtio|none]\n" + " select video card type\n", QEMU_ARCH_ALL) +STEXI +@item -vga @var{type} +@findex -vga +Select type of VGA card to emulate. Valid values for @var{type} are +@table @option +@item cirrus +Cirrus Logic GD5446 Video card. All Windows versions starting from +Windows 95 should recognize and use this graphic card. For optimal +performances, use 16 bit color depth in the guest and the host OS. +(This one is the default) +@item std +Standard VGA card with Bochs VBE extensions. If your guest OS +supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want +to use high resolution modes (>= 1280x1024x16) then you should use +this option. +@item vmware +VMWare SVGA-II compatible adapter. Use it if you have sufficiently +recent XFree86/XOrg server or Windows guest with a driver for this +card. +@item qxl +QXL paravirtual graphic card. It is VGA compatible (including VESA +2.0 VBE support). Works best with qxl guest drivers installed though. +Recommended choice when using the spice protocol. +@item tcx +(sun4m only) Sun TCX framebuffer. This is the default framebuffer for +sun4m machines and offers both 8-bit and 24-bit colour depths at a +fixed resolution of 1024x768. +@item cg3 +(sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer +for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP) +resolutions aimed at people wishing to run older Solaris versions. +@item virtio +Virtio VGA card. +@item none +Disable VGA card. +@end table +ETEXI + +DEF("full-screen", 0, QEMU_OPTION_full_screen, + "-full-screen start in full screen\n", QEMU_ARCH_ALL) +STEXI +@item -full-screen +@findex -full-screen +Start in full screen. +ETEXI + +DEF("g", 1, QEMU_OPTION_g , + "-g WxH[xDEPTH] Set the initial graphical resolution and depth\n", + QEMU_ARCH_PPC | QEMU_ARCH_SPARC) +STEXI +@item -g @var{width}x@var{height}[x@var{depth}] +@findex -g +Set the initial graphical resolution and depth (PPC, SPARC only). +ETEXI + +DEF("vnc", HAS_ARG, QEMU_OPTION_vnc , + "-vnc display start a VNC server on display\n", QEMU_ARCH_ALL) +STEXI +@item -vnc @var{display}[,@var{option}[,@var{option}[,...]]] +@findex -vnc +Normally, QEMU uses SDL to display the VGA output. With this option, +you can have QEMU listen on VNC display @var{display} and redirect the VGA +display over the VNC session. It is very useful to enable the usb +tablet device when using this option (option @option{-usbdevice +tablet}). When using the VNC display, you must use the @option{-k} +parameter to set the keyboard layout if you are not using en-us. Valid +syntax for the @var{display} is + +@table @option + +@item @var{host}:@var{d} + +TCP connections will only be allowed from @var{host} on display @var{d}. +By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can +be omitted in which case the server will accept connections from any host. + +@item unix:@var{path} + +Connections will be allowed over UNIX domain sockets where @var{path} is the +location of a unix socket to listen for connections on. + +@item none + +VNC is initialized but not started. The monitor @code{change} command +can be used to later start the VNC server. + +@end table + +Following the @var{display} value there may be one or more @var{option} flags +separated by commas. Valid options are + +@table @option + +@item reverse + +Connect to a listening VNC client via a ``reverse'' connection. The +client is specified by the @var{display}. For reverse network +connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument +is a TCP port number, not a display number. + +@item websocket + +Opens an additional TCP listening port dedicated to VNC Websocket connections. +By definition the Websocket port is 5700+@var{display}. If @var{host} is +specified connections will only be allowed from this host. +As an alternative the Websocket port could be specified by using +@code{websocket}=@var{port}. +TLS encryption for the Websocket connection is supported if the required +certificates are specified with the VNC option @option{x509}. + +@item password + +Require that password based authentication is used for client connections. + +The password must be set separately using the @code{set_password} command in +the @ref{pcsys_monitor}. The syntax to change your password is: +@code{set_password <protocol> <password>} where <protocol> could be either +"vnc" or "spice". + +If you would like to change <protocol> password expiration, you should use +@code{expire_password <protocol> <expiration-time>} where expiration time could +be one of the following options: now, never, +seconds or UNIX time of +expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800 +to make password expire on "Mon Apr 23 12:00:00 EDT 2012" (UNIX time for this +date and time). + +You can also use keywords "now" or "never" for the expiration time to +allow <protocol> password to expire immediately or never expire. + +@item tls + +Require that client use TLS when communicating with the VNC server. This +uses anonymous TLS credentials so is susceptible to a man-in-the-middle +attack. It is recommended that this option be combined with either the +@option{x509} or @option{x509verify} options. + +@item x509=@var{/path/to/certificate/dir} + +Valid if @option{tls} is specified. Require that x509 credentials are used +for negotiating the TLS session. The server will send its x509 certificate +to the client. It is recommended that a password be set on the VNC server +to provide authentication of the client when this is used. The path following +this option specifies where the x509 certificates are to be loaded from. +See the @ref{vnc_security} section for details on generating certificates. + +@item x509verify=@var{/path/to/certificate/dir} + +Valid if @option{tls} is specified. Require that x509 credentials are used +for negotiating the TLS session. The server will send its x509 certificate +to the client, and request that the client send its own x509 certificate. +The server will validate the client's certificate against the CA certificate, +and reject clients when validation fails. If the certificate authority is +trusted, this is a sufficient authentication mechanism. You may still wish +to set a password on the VNC server as a second authentication layer. The +path following this option specifies where the x509 certificates are to +be loaded from. See the @ref{vnc_security} section for details on generating +certificates. + +@item sasl + +Require that the client use SASL to authenticate with the VNC server. +The exact choice of authentication method used is controlled from the +system / user's SASL configuration file for the 'qemu' service. This +is typically found in /etc/sasl2/qemu.conf. If running QEMU as an +unprivileged user, an environment variable SASL_CONF_PATH can be used +to make it search alternate locations for the service config. +While some SASL auth methods can also provide data encryption (eg GSSAPI), +it is recommended that SASL always be combined with the 'tls' and +'x509' settings to enable use of SSL and server certificates. This +ensures a data encryption preventing compromise of authentication +credentials. See the @ref{vnc_security} section for details on using +SASL authentication. + +@item acl + +Turn on access control lists for checking of the x509 client certificate +and SASL party. For x509 certs, the ACL check is made against the +certificate's distinguished name. This is something that looks like +@code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is +made against the username, which depending on the SASL plugin, may +include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}. +When the @option{acl} flag is set, the initial access list will be +empty, with a @code{deny} policy. Thus no one will be allowed to +use the VNC server until the ACLs have been loaded. This can be +achieved using the @code{acl} monitor command. + +@item lossy + +Enable lossy compression methods (gradient, JPEG, ...). If this +option is set, VNC client may receive lossy framebuffer updates +depending on its encoding settings. Enabling this option can save +a lot of bandwidth at the expense of quality. + +@item non-adaptive + +Disable adaptive encodings. Adaptive encodings are enabled by default. +An adaptive encoding will try to detect frequently updated screen regions, +and send updates in these regions using a lossy encoding (like JPEG). +This can be really helpful to save bandwidth when playing videos. Disabling +adaptive encodings restores the original static behavior of encodings +like Tight. + +@item share=[allow-exclusive|force-shared|ignore] + +Set display sharing policy. 'allow-exclusive' allows clients to ask +for exclusive access. As suggested by the rfb spec this is +implemented by dropping other connections. Connecting multiple +clients in parallel requires all clients asking for a shared session +(vncviewer: -shared switch). This is the default. 'force-shared' +disables exclusive client access. Useful for shared desktop sessions, +where you don't want someone forgetting specify -shared disconnect +everybody else. 'ignore' completely ignores the shared flag and +allows everybody connect unconditionally. Doesn't conform to the rfb +spec but is traditional QEMU behavior. + +@end table +ETEXI + +STEXI +@end table +ETEXI +ARCHHEADING(, QEMU_ARCH_I386) + +ARCHHEADING(i386 target only:, QEMU_ARCH_I386) +STEXI +@table @option +ETEXI + +DEF("win2k-hack", 0, QEMU_OPTION_win2k_hack, + "-win2k-hack use it when installing Windows 2000 to avoid a disk full bug\n", + QEMU_ARCH_I386) +STEXI +@item -win2k-hack +@findex -win2k-hack +Use it when installing Windows 2000 to avoid a disk full bug. After +Windows 2000 is installed, you no longer need this option (this option +slows down the IDE transfers). +ETEXI + +HXCOMM Deprecated by -rtc +DEF("rtc-td-hack", 0, QEMU_OPTION_rtc_td_hack, "", QEMU_ARCH_I386) + +DEF("no-fd-bootchk", 0, QEMU_OPTION_no_fd_bootchk, + "-no-fd-bootchk disable boot signature checking for floppy disks\n", + QEMU_ARCH_I386) +STEXI +@item -no-fd-bootchk +@findex -no-fd-bootchk +Disable boot signature checking for floppy disks in BIOS. May +be needed to boot from old floppy disks. +ETEXI + +DEF("no-acpi", 0, QEMU_OPTION_no_acpi, + "-no-acpi disable ACPI\n", QEMU_ARCH_I386 | QEMU_ARCH_ARM) +STEXI +@item -no-acpi +@findex -no-acpi +Disable ACPI (Advanced Configuration and Power Interface) support. Use +it if your guest OS complains about ACPI problems (PC target machine +only). +ETEXI + +DEF("no-hpet", 0, QEMU_OPTION_no_hpet, + "-no-hpet disable HPET\n", QEMU_ARCH_I386) +STEXI +@item -no-hpet +@findex -no-hpet +Disable HPET support. +ETEXI + +DEF("acpitable", HAS_ARG, QEMU_OPTION_acpitable, + "-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" + " ACPI table description\n", QEMU_ARCH_I386) +STEXI +@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}]...] +@findex -acpitable +Add ACPI table with specified header fields and context from specified files. +For file=, take whole ACPI table from the specified files, including all +ACPI headers (possible overridden by other options). +For data=, only data +portion of the table is used, all header information is specified in the +command line. +ETEXI + +DEF("smbios", HAS_ARG, QEMU_OPTION_smbios, + "-smbios file=binary\n" + " load SMBIOS entry from binary file\n" + "-smbios type=0[,vendor=str][,version=str][,date=str][,release=%d.%d]\n" + " [,uefi=on|off]\n" + " specify SMBIOS type 0 fields\n" + "-smbios type=1[,manufacturer=str][,product=str][,version=str][,serial=str]\n" + " [,uuid=uuid][,sku=str][,family=str]\n" + " specify SMBIOS type 1 fields\n" + "-smbios type=2[,manufacturer=str][,product=str][,version=str][,serial=str]\n" + " [,asset=str][,location=str]\n" + " specify SMBIOS type 2 fields\n" + "-smbios type=3[,manufacturer=str][,version=str][,serial=str][,asset=str]\n" + " [,sku=str]\n" + " specify SMBIOS type 3 fields\n" + "-smbios type=4[,sock_pfx=str][,manufacturer=str][,version=str][,serial=str]\n" + " [,asset=str][,part=str]\n" + " specify SMBIOS type 4 fields\n" + "-smbios type=17[,loc_pfx=str][,bank=str][,manufacturer=str][,serial=str]\n" + " [,asset=str][,part=str][,speed=%d]\n" + " specify SMBIOS type 17 fields\n", + QEMU_ARCH_I386) +STEXI +@item -smbios file=@var{binary} +@findex -smbios +Load SMBIOS entry from binary file. + +@item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off] +Specify SMBIOS type 0 fields + +@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}] +Specify SMBIOS type 1 fields + +@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}] +Specify SMBIOS type 2 fields + +@item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}] +Specify SMBIOS type 3 fields + +@item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}] +Specify SMBIOS type 4 fields + +@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}] +Specify SMBIOS type 17 fields +ETEXI + +STEXI +@end table +ETEXI +DEFHEADING() + +DEFHEADING(Network options:) +STEXI +@table @option +ETEXI + +HXCOMM Legacy slirp options (now moved to -net user): +#ifdef CONFIG_SLIRP +DEF("tftp", HAS_ARG, QEMU_OPTION_tftp, "", QEMU_ARCH_ALL) +DEF("bootp", HAS_ARG, QEMU_OPTION_bootp, "", QEMU_ARCH_ALL) +DEF("redir", HAS_ARG, QEMU_OPTION_redir, "", QEMU_ARCH_ALL) +#ifndef _WIN32 +DEF("smb", HAS_ARG, QEMU_OPTION_smb, "", QEMU_ARCH_ALL) +#endif +#endif + +DEF("netdev", HAS_ARG, QEMU_OPTION_netdev, +#ifdef CONFIG_SLIRP + "-netdev user,id=str[,net=addr[/mask]][,host=addr][,restrict=on|off]\n" + " [,hostname=host][,dhcpstart=addr][,dns=addr][,dnssearch=domain][,tftp=dir]\n" + " [,bootfile=f][,hostfwd=rule][,guestfwd=rule]" +#ifndef _WIN32 + "[,smb=dir[,smbserver=addr]]\n" +#endif + " configure a user mode network backend with ID 'str',\n" + " its DHCP server and optional services\n" +#endif +#ifdef _WIN32 + "-netdev tap,id=str,ifname=name\n" + " configure a host TAP network backend with ID 'str'\n" +#else + "-netdev tap,id=str[,fd=h][,fds=x:y:...:z][,ifname=name][,script=file][,downscript=dfile]\n" + " [,helper=helper][,sndbuf=nbytes][,vnet_hdr=on|off][,vhost=on|off]\n" + " [,vhostfd=h][,vhostfds=x:y:...:z][,vhostforce=on|off][,queues=n]\n" + " configure a host TAP network backend with ID 'str'\n" + " use network scripts 'file' (default=" DEFAULT_NETWORK_SCRIPT ")\n" + " to configure it and 'dfile' (default=" DEFAULT_NETWORK_DOWN_SCRIPT ")\n" + " to deconfigure it\n" + " use '[down]script=no' to disable script execution\n" + " use network helper 'helper' (default=" DEFAULT_BRIDGE_HELPER ") to\n" + " configure it\n" + " use 'fd=h' to connect to an already opened TAP interface\n" + " use 'fds=x:y:...:z' to connect to already opened multiqueue capable TAP interfaces\n" + " use 'sndbuf=nbytes' to limit the size of the send buffer (the\n" + " default is disabled 'sndbuf=0' to enable flow control set 'sndbuf=1048576')\n" + " use vnet_hdr=off to avoid enabling the IFF_VNET_HDR tap flag\n" + " use vnet_hdr=on to make the lack of IFF_VNET_HDR support an error condition\n" + " use vhost=on to enable experimental in kernel accelerator\n" + " (only has effect for virtio guests which use MSIX)\n" + " use vhostforce=on to force vhost on for non-MSIX virtio guests\n" + " use 'vhostfd=h' to connect to an already opened vhost net device\n" + " use 'vhostfds=x:y:...:z to connect to multiple already opened vhost net devices\n" + " use 'queues=n' to specify the number of queues to be created for multiqueue TAP\n" + "-netdev bridge,id=str[,br=bridge][,helper=helper]\n" + " configure a host TAP network backend with ID 'str' that is\n" + " connected to a bridge (default=" DEFAULT_BRIDGE_INTERFACE ")\n" + " using the program 'helper (default=" DEFAULT_BRIDGE_HELPER ")\n" +#endif +#ifdef __linux__ + "-netdev l2tpv3,id=str,src=srcaddr,dst=dstaddr[,srcport=srcport][,dstport=dstport]\n" + " [,rxsession=rxsession],txsession=txsession[,ipv6=on/off][,udp=on/off]\n" + " [,cookie64=on/off][,counter][,pincounter][,txcookie=txcookie]\n" + " [,rxcookie=rxcookie][,offset=offset]\n" + " configure a network backend with ID 'str' connected to\n" + " an Ethernet over L2TPv3 pseudowire.\n" + " Linux kernel 3.3+ as well as most routers can talk\n" + " L2TPv3. This transport allows connecting a VM to a VM,\n" + " VM to a router and even VM to Host. It is a nearly-universal\n" + " standard (RFC3391). Note - this implementation uses static\n" + " pre-configured tunnels (same as the Linux kernel).\n" + " use 'src=' to specify source address\n" + " use 'dst=' to specify destination address\n" + " use 'udp=on' to specify udp encapsulation\n" + " use 'srcport=' to specify source udp port\n" + " use 'dstport=' to specify destination udp port\n" + " use 'ipv6=on' to force v6\n" + " L2TPv3 uses cookies to prevent misconfiguration as\n" + " well as a weak security measure\n" + " use 'rxcookie=0x012345678' to specify a rxcookie\n" + " use 'txcookie=0x012345678' to specify a txcookie\n" + " use 'cookie64=on' to set cookie size to 64 bit, otherwise 32\n" + " use 'counter=off' to force a 'cut-down' L2TPv3 with no counter\n" + " use 'pincounter=on' to work around broken counter handling in peer\n" + " use 'offset=X' to add an extra offset between header and data\n" +#endif + "-netdev socket,id=str[,fd=h][,listen=[host]:port][,connect=host:port]\n" + " configure a network backend to connect to another network\n" + " using a socket connection\n" + "-netdev socket,id=str[,fd=h][,mcast=maddr:port[,localaddr=addr]]\n" + " configure a network backend to connect to a multicast maddr and port\n" + " use 'localaddr=addr' to specify the host address to send packets from\n" + "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n" + " configure a network backend to connect to another network\n" + " using an UDP tunnel\n" +#ifdef CONFIG_VDE + "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n" + " configure a network backend to connect to port 'n' of a vde switch\n" + " running on host and listening for incoming connections on 'socketpath'.\n" + " Use group 'groupname' and mode 'octalmode' to change default\n" + " ownership and permissions for communication port.\n" +#endif +#ifdef CONFIG_NETMAP + "-netdev netmap,id=str,ifname=name[,devname=nmname]\n" + " attach to the existing netmap-enabled network interface 'name', or to a\n" + " VALE port (created on the fly) called 'name' ('nmname' is name of the \n" + " netmap device, defaults to '/dev/netmap')\n" +#endif + "-netdev vhost-user,id=str,chardev=dev[,vhostforce=on|off]\n" + " configure a vhost-user network, backed by a chardev 'dev'\n" + "-netdev hubport,id=str,hubid=n\n" + " configure a hub port on QEMU VLAN 'n'\n", QEMU_ARCH_ALL) +DEF("net", HAS_ARG, QEMU_OPTION_net, + "-net nic[,vlan=n][,macaddr=mac][,model=type][,name=str][,addr=str][,vectors=v]\n" + " old way to create a new NIC and connect it to VLAN 'n'\n" + " (use the '-device devtype,netdev=str' option if possible instead)\n" + "-net dump[,vlan=n][,file=f][,len=n]\n" + " dump traffic on vlan 'n' to file 'f' (max n bytes per packet)\n" + "-net none use it alone to have zero network devices. If no -net option\n" + " is provided, the default is '-net nic -net user'\n" + "-net [" +#ifdef CONFIG_SLIRP + "user|" +#endif + "tap|" + "bridge|" +#ifdef CONFIG_VDE + "vde|" +#endif +#ifdef CONFIG_NETMAP + "netmap|" +#endif + "socket][,vlan=n][,option][,option][,...]\n" + " old way to initialize a host network interface\n" + " (use the -netdev option if possible instead)\n", QEMU_ARCH_ALL) +STEXI +@item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}] +@findex -net +Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n} += 0 is the default). The NIC is an e1000 by default on the PC +target. Optionally, the MAC address can be changed to @var{mac}, the +device address set to @var{addr} (PCI cards only), +and a @var{name} can be assigned for use in monitor commands. +Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors +that the card should have; this option currently only affects virtio cards; set +@var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single +NIC is created. QEMU can emulate several different models of network card. +Valid values for @var{type} are +@code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er}, +@code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139}, +@code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}. +Not all devices are supported on all targets. Use @code{-net nic,model=help} +for a list of available devices for your target. + +@item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...] +@findex -netdev +@item -net user[,@var{option}][,@var{option}][,...] +Use the user mode network stack which requires no administrator +privilege to run. Valid options are: + +@table @option +@item vlan=@var{n} +Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default). + +@item id=@var{id} +@itemx name=@var{name} +Assign symbolic name for use in monitor commands. + +@item net=@var{addr}[/@var{mask}] +Set IP network address the guest will see. Optionally specify the netmask, +either in the form a.b.c.d or as number of valid top-most bits. Default is +10.0.2.0/24. + +@item host=@var{addr} +Specify the guest-visible address of the host. Default is the 2nd IP in the +guest network, i.e. x.x.x.2. + +@item restrict=on|off +If this option is enabled, the guest will be isolated, i.e. it will not be +able to contact the host and no guest IP packets will be routed over the host +to the outside. This option does not affect any explicitly set forwarding rules. + +@item hostname=@var{name} +Specifies the client hostname reported by the built-in DHCP server. + +@item dhcpstart=@var{addr} +Specify the first of the 16 IPs the built-in DHCP server can assign. Default +is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31. + +@item dns=@var{addr} +Specify the guest-visible address of the virtual nameserver. The address must +be different from the host address. Default is the 3rd IP in the guest network, +i.e. x.x.x.3. + +@item dnssearch=@var{domain} +Provides an entry for the domain-search list sent by the built-in +DHCP server. More than one domain suffix can be transmitted by specifying +this option multiple times. If supported, this will cause the guest to +automatically try to append the given domain suffix(es) in case a domain name +can not be resolved. + +Example: +@example +qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...] +@end example + +@item tftp=@var{dir} +When using the user mode network stack, activate a built-in TFTP +server. The files in @var{dir} will be exposed as the root of a TFTP server. +The TFTP client on the guest must be configured in binary mode (use the command +@code{bin} of the Unix TFTP client). + +@item bootfile=@var{file} +When using the user mode network stack, broadcast @var{file} as the BOOTP +filename. In conjunction with @option{tftp}, this can be used to network boot +a guest from a local directory. + +Example (using pxelinux): +@example +qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0 +@end example + +@item smb=@var{dir}[,smbserver=@var{addr}] +When using the user mode network stack, activate a built-in SMB +server so that Windows OSes can access to the host files in @file{@var{dir}} +transparently. The IP address of the SMB server can be set to @var{addr}. By +default the 4th IP in the guest network is used, i.e. x.x.x.4. + +In the guest Windows OS, the line: +@example +10.0.2.4 smbserver +@end example +must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me) +or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000). + +Then @file{@var{dir}} can be accessed in @file{\\smbserver\qemu}. + +Note that a SAMBA server must be installed on the host OS. +QEMU was tested successfully with smbd versions from Red Hat 9, +Fedora Core 3 and OpenSUSE 11.x. + +@item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport} +Redirect incoming TCP or UDP connections to the host port @var{hostport} to +the guest IP address @var{guestaddr} on guest port @var{guestport}. If +@var{guestaddr} is not specified, its value is x.x.x.15 (default first address +given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can +be bound to a specific host interface. If no connection type is set, TCP is +used. This option can be given multiple times. + +For example, to redirect host X11 connection from screen 1 to guest +screen 0, use the following: + +@example +# on the host +qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...] +# this host xterm should open in the guest X11 server +xterm -display :1 +@end example + +To redirect telnet connections from host port 5555 to telnet port on +the guest, use the following: + +@example +# on the host +qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...] +telnet localhost 5555 +@end example + +Then when you use on the host @code{telnet localhost 5555}, you +connect to the guest telnet server. + +@item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev} +@itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command} +Forward guest TCP connections to the IP address @var{server} on port @var{port} +to the character device @var{dev} or to a program executed by @var{cmd:command} +which gets spawned for each connection. This option can be given multiple times. + +You can either use a chardev directly and have that one used throughout QEMU's +lifetime, like in the following example: + +@example +# open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever +# the guest accesses it +qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...] +@end example + +Or you can execute a command on every TCP connection established by the guest, +so that QEMU behaves similar to an inetd process for that virtual server: + +@example +# call "netcat 10.10.1.1 4321" on every TCP connection to 10.0.2.100:1234 +# and connect the TCP stream to its stdin/stdout +qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321' +@end example + +@end table + +Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still +processed and applied to -net user. Mixing them with the new configuration +syntax gives undefined results. Their use for new applications is discouraged +as they will be removed from future versions. + +@item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}] +@itemx -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}] +Connect the host TAP network interface @var{name} to VLAN @var{n}. + +Use the network script @var{file} to configure it and the network script +@var{dfile} to deconfigure it. If @var{name} is not provided, the OS +automatically provides one. The default network configure script is +@file{/etc/qemu-ifup} and the default network deconfigure script is +@file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no} +to disable script execution. + +If running QEMU as an unprivileged user, use the network helper +@var{helper} to configure the TAP interface. The default network +helper executable is @file{/path/to/qemu-bridge-helper}. + +@option{fd}=@var{h} can be used to specify the handle of an already +opened host TAP interface. + +Examples: + +@example +#launch a QEMU instance with the default network script +qemu-system-i386 linux.img -net nic -net tap +@end example + +@example +#launch a QEMU instance with two NICs, each one connected +#to a TAP device +qemu-system-i386 linux.img \ + -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \ + -net nic,vlan=1 -net tap,vlan=1,ifname=tap1 +@end example + +@example +#launch a QEMU instance with the default network helper to +#connect a TAP device to bridge br0 +qemu-system-i386 linux.img \ + -net nic -net tap,"helper=/path/to/qemu-bridge-helper" +@end example + +@item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}] +@itemx -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}] +Connect a host TAP network interface to a host bridge device. + +Use the network helper @var{helper} to configure the TAP interface and +attach it to the bridge. The default network helper executable is +@file{/path/to/qemu-bridge-helper} and the default bridge +device is @file{br0}. + +Examples: + +@example +#launch a QEMU instance with the default network helper to +#connect a TAP device to bridge br0 +qemu-system-i386 linux.img -net bridge -net nic,model=virtio +@end example + +@example +#launch a QEMU instance with the default network helper to +#connect a TAP device to bridge qemubr0 +qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio +@end example + +@item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] +@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}] + +Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual +machine using a TCP socket connection. If @option{listen} is +specified, QEMU waits for incoming connections on @var{port} +(@var{host} is optional). @option{connect} is used to connect to +another QEMU instance using the @option{listen} option. @option{fd}=@var{h} +specifies an already opened TCP socket. + +Example: +@example +# launch a first QEMU instance +qemu-system-i386 linux.img \ + -net nic,macaddr=52:54:00:12:34:56 \ + -net socket,listen=:1234 +# connect the VLAN 0 of this instance to the VLAN 0 +# of the first instance +qemu-system-i386 linux.img \ + -net nic,macaddr=52:54:00:12:34:57 \ + -net socket,connect=127.0.0.1:1234 +@end example + +@item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] +@itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]] + +Create a VLAN @var{n} shared with another QEMU virtual +machines using a UDP multicast socket, effectively making a bus for +every QEMU with same multicast address @var{maddr} and @var{port}. +NOTES: +@enumerate +@item +Several QEMU can be running on different hosts and share same bus (assuming +correct multicast setup for these hosts). +@item +mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see +@url{http://user-mode-linux.sf.net}. +@item +Use @option{fd=h} to specify an already opened UDP multicast socket. +@end enumerate + +Example: +@example +# launch one QEMU instance +qemu-system-i386 linux.img \ + -net nic,macaddr=52:54:00:12:34:56 \ + -net socket,mcast=230.0.0.1:1234 +# launch another QEMU instance on same "bus" +qemu-system-i386 linux.img \ + -net nic,macaddr=52:54:00:12:34:57 \ + -net socket,mcast=230.0.0.1:1234 +# launch yet another QEMU instance on same "bus" +qemu-system-i386 linux.img \ + -net nic,macaddr=52:54:00:12:34:58 \ + -net socket,mcast=230.0.0.1:1234 +@end example + +Example (User Mode Linux compat.): +@example +# launch QEMU instance (note mcast address selected +# is UML's default) +qemu-system-i386 linux.img \ + -net nic,macaddr=52:54:00:12:34:56 \ + -net socket,mcast=239.192.168.1:1102 +# launch UML +/path/to/linux ubd0=/path/to/root_fs eth0=mcast +@end example + +Example (send packets from host's 1.2.3.4): +@example +qemu-system-i386 linux.img \ + -net nic,macaddr=52:54:00:12:34:56 \ + -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4 +@end example + +@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}] +@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}] +Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular +protocol to transport Ethernet (and other Layer 2) data frames between +two systems. It is present in routers, firewalls and the Linux kernel +(from version 3.3 onwards). + +This transport allows a VM to communicate to another VM, router or firewall directly. + +@item src=@var{srcaddr} + source address (mandatory) +@item dst=@var{dstaddr} + destination address (mandatory) +@item udp + select udp encapsulation (default is ip). +@item srcport=@var{srcport} + source udp port. +@item dstport=@var{dstport} + destination udp port. +@item ipv6 + force v6, otherwise defaults to v4. +@item rxcookie=@var{rxcookie} +@itemx txcookie=@var{txcookie} + Cookies are a weak form of security in the l2tpv3 specification. +Their function is mostly to prevent misconfiguration. By default they are 32 +bit. +@item cookie64 + Set cookie size to 64 bit instead of the default 32 +@item counter=off + Force a 'cut-down' L2TPv3 with no counter as in +draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00 +@item pincounter=on + Work around broken counter handling in peer. This may also help on +networks which have packet reorder. +@item offset=@var{offset} + Add an extra offset between header and data + +For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan +on the remote Linux host 1.2.3.4: +@example +# Setup tunnel on linux host using raw ip as encapsulation +# on 1.2.3.4 +ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \ + encap udp udp_sport 16384 udp_dport 16384 +ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \ + 0xFFFFFFFF peer_session_id 0xFFFFFFFF +ifconfig vmtunnel0 mtu 1500 +ifconfig vmtunnel0 up +brctl addif br-lan vmtunnel0 + + +# on 4.3.2.1 +# launch QEMU instance - if your network has reorder or is very lossy add ,pincounter + +qemu-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 + + +@end example + +@item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] +@itemx -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}] +Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and +listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname} +and MODE @var{octalmode} to change default ownership and permissions for +communication port. This option is only available if QEMU has been compiled +with vde support enabled. + +Example: +@example +# launch vde switch +vde_switch -F -sock /tmp/myswitch +# launch QEMU instance +qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch +@end example + +@item -netdev hubport,id=@var{id},hubid=@var{hubid} + +Create a hub port on QEMU "vlan" @var{hubid}. + +The hubport netdev lets you connect a NIC to a QEMU "vlan" instead of a single +netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the +required hub automatically. + +@item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off] + +Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should +be a unix domain socket backed one. The vhost-user uses a specifically defined +protocol to pass vhost ioctl replacement messages to an application on the other +end of the socket. On non-MSIX guests, the feature can be forced with +@var{vhostforce}. + +Example: +@example +qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \ + -numa node,memdev=mem \ + -chardev socket,path=/path/to/socket \ + -netdev type=vhost-user,id=net0,chardev=chr0 \ + -device virtio-net-pci,netdev=net0 +@end example + +@item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}] +Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default). +At most @var{len} bytes (64k by default) per packet are stored. The file format is +libpcap, so it can be analyzed with tools such as tcpdump or Wireshark. + +@item -net none +Indicate that no network devices should be configured. It is used to +override the default configuration (@option{-net nic -net user}) which +is activated if no @option{-net} options are provided. +ETEXI + +STEXI +@end table +ETEXI +DEFHEADING() + +DEFHEADING(Character device options:) +STEXI + +The general form of a character device option is: +@table @option +ETEXI + +DEF("chardev", HAS_ARG, QEMU_OPTION_chardev, + "-chardev null,id=id[,mux=on|off]\n" + "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n" + " [,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off] (tcp)\n" + "-chardev socket,id=id,path=path[,server][,nowait][,telnet][,reconnect=seconds][,mux=on|off] (unix)\n" + "-chardev udp,id=id[,host=host],port=port[,localaddr=localaddr]\n" + " [,localport=localport][,ipv4][,ipv6][,mux=on|off]\n" + "-chardev msmouse,id=id[,mux=on|off]\n" + "-chardev vc,id=id[[,width=width][,height=height]][[,cols=cols][,rows=rows]]\n" + " [,mux=on|off]\n" + "-chardev ringbuf,id=id[,size=size]\n" + "-chardev file,id=id,path=path[,mux=on|off]\n" + "-chardev pipe,id=id,path=path[,mux=on|off]\n" +#ifdef _WIN32 + "-chardev console,id=id[,mux=on|off]\n" + "-chardev serial,id=id,path=path[,mux=on|off]\n" +#else + "-chardev pty,id=id[,mux=on|off]\n" + "-chardev stdio,id=id[,mux=on|off][,signal=on|off]\n" +#endif +#ifdef CONFIG_BRLAPI + "-chardev braille,id=id[,mux=on|off]\n" +#endif +#if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \ + || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) + "-chardev serial,id=id,path=path[,mux=on|off]\n" + "-chardev tty,id=id,path=path[,mux=on|off]\n" +#endif +#if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__) + "-chardev parallel,id=id,path=path[,mux=on|off]\n" + "-chardev parport,id=id,path=path[,mux=on|off]\n" +#endif +#if defined(CONFIG_SPICE) + "-chardev spicevmc,id=id,name=name[,debug=debug]\n" + "-chardev spiceport,id=id,name=name[,debug=debug]\n" +#endif + , QEMU_ARCH_ALL +) + +STEXI +@item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}] +@findex -chardev +Backend is one of: +@option{null}, +@option{socket}, +@option{udp}, +@option{msmouse}, +@option{vc}, +@option{ringbuf}, +@option{file}, +@option{pipe}, +@option{console}, +@option{serial}, +@option{pty}, +@option{stdio}, +@option{braille}, +@option{tty}, +@option{parallel}, +@option{parport}, +@option{spicevmc}. +@option{spiceport}. +The specific backend will determine the applicable options. + +All devices must have an id, which can be any string up to 127 characters long. +It is used to uniquely identify this device in other command line directives. + +A character device may be used in multiplexing mode by multiple front-ends. +The key sequence of @key{Control-a} and @key{c} will rotate the input focus +between attached front-ends. Specify @option{mux=on} to enable this mode. + +Options to each backend are described below. + +@item -chardev null ,id=@var{id} +A void device. This device will not emit any data, and will drop any data it +receives. The null backend does not take any options. + +@item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}] + +Create a two-way stream socket, which can be either a TCP or a unix socket. A +unix socket will be created if @option{path} is specified. Behaviour is +undefined if TCP options are specified for a unix socket. + +@option{server} specifies that the socket shall be a listening socket. + +@option{nowait} specifies that QEMU should not block waiting for a client to +connect to a listening socket. + +@option{telnet} specifies that traffic on the socket should interpret telnet +escape sequences. + +@option{reconnect} sets the timeout for reconnecting on non-server sockets when +the remote end goes away. qemu will delay this many seconds and then attempt +to reconnect. Zero disables reconnecting, and is the default. + +TCP and unix socket options are given below: + +@table @option + +@item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay] + +@option{host} for a listening socket specifies the local address to be bound. +For a connecting socket species the remote host to connect to. @option{host} is +optional for listening sockets. If not specified it defaults to @code{0.0.0.0}. + +@option{port} for a listening socket specifies the local port to be bound. For a +connecting socket specifies the port on the remote host to connect to. +@option{port} can be given as either a port number or a service name. +@option{port} is required. + +@option{to} is only relevant to listening sockets. If it is specified, and +@option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up +to and including @option{to} until it succeeds. @option{to} must be specified +as a port number. + +@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. +If neither is specified the socket may use either protocol. + +@option{nodelay} disables the Nagle algorithm. + +@item unix options: path=@var{path} + +@option{path} specifies the local path of the unix socket. @option{path} is +required. + +@end table + +@item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6] + +Sends all traffic from the guest to a remote host over UDP. + +@option{host} specifies the remote host to connect to. If not specified it +defaults to @code{localhost}. + +@option{port} specifies the port on the remote host to connect to. @option{port} +is required. + +@option{localaddr} specifies the local address to bind to. If not specified it +defaults to @code{0.0.0.0}. + +@option{localport} specifies the local port to bind to. If not specified any +available local port will be used. + +@option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used. +If neither is specified the device may use either protocol. + +@item -chardev msmouse ,id=@var{id} + +Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not +take any options. + +@item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]] + +Connect to a QEMU text console. @option{vc} may optionally be given a specific +size. + +@option{width} and @option{height} specify the width and height respectively of +the console, in pixels. + +@option{cols} and @option{rows} specify that the console be sized to fit a text +console with the given dimensions. + +@item -chardev ringbuf ,id=@var{id} [,size=@var{size}] + +Create a ring buffer with fixed size @option{size}. +@var{size} must be a power of two, and defaults to @code{64K}). + +@item -chardev file ,id=@var{id} ,path=@var{path} + +Log all traffic received from the guest to a file. + +@option{path} specifies the path of the file to be opened. This file will be +created if it does not already exist, and overwritten if it does. @option{path} +is required. + +@item -chardev pipe ,id=@var{id} ,path=@var{path} + +Create a two-way connection to the guest. The behaviour differs slightly between +Windows hosts and other hosts: + +On Windows, a single duplex pipe will be created at +@file{\\.pipe\@option{path}}. + +On other hosts, 2 pipes will be created called @file{@option{path}.in} and +@file{@option{path}.out}. Data written to @file{@option{path}.in} will be +received by the guest. Data written by the guest can be read from +@file{@option{path}.out}. QEMU will not create these fifos, and requires them to +be present. + +@option{path} forms part of the pipe path as described above. @option{path} is +required. + +@item -chardev console ,id=@var{id} + +Send traffic from the guest to QEMU's standard output. @option{console} does not +take any options. + +@option{console} is only available on Windows hosts. + +@item -chardev serial ,id=@var{id} ,path=@option{path} + +Send traffic from the guest to a serial device on the host. + +On Unix hosts serial will actually accept any tty device, +not only serial lines. + +@option{path} specifies the name of the serial device to open. + +@item -chardev pty ,id=@var{id} + +Create a new pseudo-terminal on the host and connect to it. @option{pty} does +not take any options. + +@option{pty} is not available on Windows hosts. + +@item -chardev stdio ,id=@var{id} [,signal=on|off] +Connect to standard input and standard output of the QEMU process. + +@option{signal} controls if signals are enabled on the terminal, that includes +exiting QEMU with the key sequence @key{Control-c}. This option is enabled by +default, use @option{signal=off} to disable it. + +@option{stdio} is not available on Windows hosts. + +@item -chardev braille ,id=@var{id} + +Connect to a local BrlAPI server. @option{braille} does not take any options. + +@item -chardev tty ,id=@var{id} ,path=@var{path} + +@option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and +DragonFlyBSD hosts. It is an alias for @option{serial}. + +@option{path} specifies the path to the tty. @option{path} is required. + +@item -chardev parallel ,id=@var{id} ,path=@var{path} +@itemx -chardev parport ,id=@var{id} ,path=@var{path} + +@option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts. + +Connect to a local parallel port. + +@option{path} specifies the path to the parallel port device. @option{path} is +required. + +@item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name} + +@option{spicevmc} is only available when spice support is built in. + +@option{debug} debug level for spicevmc + +@option{name} name of spice channel to connect to + +Connect to a spice virtual machine channel, such as vdiport. + +@item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name} + +@option{spiceport} is only available when spice support is built in. + +@option{debug} debug level for spicevmc + +@option{name} name of spice port to connect to + +Connect to a spice port, allowing a Spice client to handle the traffic +identified by a name (preferably a fqdn). +ETEXI + +STEXI +@end table +ETEXI +DEFHEADING() + +DEFHEADING(Device URL Syntax:) +STEXI + +In addition to using normal file images for the emulated storage devices, +QEMU can also use networked resources such as iSCSI devices. These are +specified using a special URL syntax. + +@table @option +@item iSCSI +iSCSI support allows QEMU to access iSCSI resources directly and use as +images for the guest storage. Both disk and cdrom images are supported. + +Syntax for specifying iSCSI LUNs is +``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>'' + +By default qemu will use the iSCSI initiator-name +'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command +line or a configuration file. + +Since version Qemu 2.4 it is possible to specify a iSCSI request timeout to detect +stalled requests and force a reestablishment of the session. The timeout +is specified in seconds. The default is 0 which means no timeout. Libiscsi +1.15.0 or greater is required for this feature. + +Example (without authentication): +@example +qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \ + -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \ + -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 +@end example + +Example (CHAP username/password via URL): +@example +qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1 +@end example + +Example (CHAP username/password via environment variables): +@example +LIBISCSI_CHAP_USERNAME="user" \ +LIBISCSI_CHAP_PASSWORD="password" \ +qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1 +@end example + +iSCSI support is an optional feature of QEMU and only available when +compiled and linked against libiscsi. +ETEXI +DEF("iscsi", HAS_ARG, QEMU_OPTION_iscsi, + "-iscsi [user=user][,password=password]\n" + " [,header-digest=CRC32C|CR32C-NONE|NONE-CRC32C|NONE\n" + " [,initiator-name=initiator-iqn][,id=target-iqn]\n" + " [,timeout=timeout]\n" + " iSCSI session parameters\n", QEMU_ARCH_ALL) +STEXI + +iSCSI parameters such as username and password can also be specified via +a configuration file. See qemu-doc for more information and examples. + +@item NBD +QEMU supports NBD (Network Block Devices) both using TCP protocol as well +as Unix Domain Sockets. + +Syntax for specifying a NBD device using TCP +``nbd:<server-ip>:<port>[:exportname=<export>]'' + +Syntax for specifying a NBD device using Unix Domain Sockets +``nbd:unix:<domain-socket>[:exportname=<export>]'' + + +Example for TCP +@example +qemu-system-i386 --drive file=nbd:192.0.2.1:30000 +@end example + +Example for Unix Domain Sockets +@example +qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket +@end example + +@item SSH +QEMU supports SSH (Secure Shell) access to remote disks. + +Examples: +@example +qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img +qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img +@end example + +Currently authentication must be done using ssh-agent. Other +authentication methods may be supported in future. + +@item Sheepdog +Sheepdog is a distributed storage system for QEMU. +QEMU supports using either local sheepdog devices or remote networked +devices. + +Syntax for specifying a sheepdog device +@example +sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag] +@end example + +Example +@example +qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine +@end example + +See also @url{http://http://www.osrg.net/sheepdog/}. + +@item GlusterFS +GlusterFS is an user space distributed file system. +QEMU supports the use of GlusterFS volumes for hosting VM disk images using +TCP, Unix Domain Sockets and RDMA transport protocols. + +Syntax for specifying a VM disk image on GlusterFS volume is +@example +gluster[+transport]://[server[:port]]/volname/image[?socket=...] +@end example + + +Example +@example +qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img +@end example + +See also @url{http://www.gluster.org}. + +@item HTTP/HTTPS/FTP/FTPS/TFTP +QEMU supports read-only access to files accessed over http(s), ftp(s) and tftp. + +Syntax using a single filename: +@example +<protocol>://[<username>[:<password>]@@]<host>/<path> +@end example + +where: +@table @option +@item protocol +'http', 'https', 'ftp', 'ftps', or 'tftp'. + +@item username +Optional username for authentication to the remote server. + +@item password +Optional password for authentication to the remote server. + +@item host +Address of the remote server. + +@item path +Path on the remote server, including any query string. +@end table + +The following options are also supported: +@table @option +@item url +The full URL when passing options to the driver explicitly. + +@item readahead +The amount of data to read ahead with each range request to the remote server. +This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it +does not have a suffix, it will be assumed to be in bytes. The value must be a +multiple of 512 bytes. It defaults to 256k. + +@item sslverify +Whether to verify the remote server's certificate when connecting over SSL. It +can have the value 'on' or 'off'. It defaults to 'on'. + +@item cookie +Send this cookie (it can also be a list of cookies separated by ';') with +each outgoing request. Only supported when using protocols such as HTTP +which support cookies, otherwise ignored. + +@item timeout +Set the timeout in seconds of the CURL connection. This timeout is the time +that CURL waits for a response from the remote server to get the size of the +image to be downloaded. If not set, the default timeout of 5 seconds is used. +@end table + +Note that when passing options to qemu explicitly, @option{driver} is the value +of <protocol>. + +Example: boot from a remote Fedora 20 live ISO image +@example +qemu-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 + +qemu-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 +@end example + +Example: boot from a remote Fedora 20 cloud image using a local overlay for +writes, copy-on-read, and a readahead of 64k +@example +qemu-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 + +qemu-system-x86_64 -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on +@end example + +Example: boot from an image stored on a VMware vSphere server with a self-signed +certificate using a local overlay for writes, a readahead of 64k and a timeout +of 10 seconds. +@example +qemu-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 + +qemu-system-x86_64 -drive file=/tmp/test.qcow2 +@end example +ETEXI + +STEXI +@end table +ETEXI + +DEFHEADING(Bluetooth(R) options:) +STEXI +@table @option +ETEXI + +DEF("bt", HAS_ARG, QEMU_OPTION_bt, \ + "-bt hci,null dumb bluetooth HCI - doesn't respond to commands\n" \ + "-bt hci,host[:id]\n" \ + " use host's HCI with the given name\n" \ + "-bt hci[,vlan=n]\n" \ + " emulate a standard HCI in virtual scatternet 'n'\n" \ + "-bt vhci[,vlan=n]\n" \ + " add host computer to virtual scatternet 'n' using VHCI\n" \ + "-bt device:dev[,vlan=n]\n" \ + " emulate a bluetooth device 'dev' in scatternet 'n'\n", + QEMU_ARCH_ALL) +STEXI +@item -bt hci[...] +@findex -bt +Defines the function of the corresponding Bluetooth HCI. -bt options +are matched with the HCIs present in the chosen machine type. For +example when emulating a machine with only one HCI built into it, only +the first @code{-bt hci[...]} option is valid and defines the HCI's +logic. The Transport Layer is decided by the machine type. Currently +the machines @code{n800} and @code{n810} have one HCI and all other +machines have none. + +@anchor{bt-hcis} +The following three types are recognized: + +@table @option +@item -bt hci,null +(default) The corresponding Bluetooth HCI assumes no internal logic +and will not respond to any HCI commands or emit events. + +@item -bt hci,host[:@var{id}] +(@code{bluez} only) The corresponding HCI passes commands / events +to / from the physical HCI identified by the name @var{id} (default: +@code{hci0}) on the computer running QEMU. Only available on @code{bluez} +capable systems like Linux. + +@item -bt hci[,vlan=@var{n}] +Add a virtual, standard HCI that will participate in the Bluetooth +scatternet @var{n} (default @code{0}). Similarly to @option{-net} +VLANs, devices inside a bluetooth network @var{n} can only communicate +with other devices in the same network (scatternet). +@end table + +@item -bt vhci[,vlan=@var{n}] +(Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached +to the host bluetooth stack instead of to the emulated target. This +allows the host and target machines to participate in a common scatternet +and communicate. Requires the Linux @code{vhci} driver installed. Can +be used as following: + +@example +qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5 +@end example + +@item -bt device:@var{dev}[,vlan=@var{n}] +Emulate a bluetooth device @var{dev} and place it in network @var{n} +(default @code{0}). QEMU can only emulate one type of bluetooth devices +currently: + +@table @option +@item keyboard +Virtual wireless keyboard implementing the HIDP bluetooth profile. +@end table +ETEXI + +STEXI +@end table +ETEXI +DEFHEADING() + +#ifdef CONFIG_TPM +DEFHEADING(TPM device options:) + +DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \ + "-tpmdev passthrough,id=id[,path=path][,cancel-path=path]\n" + " use path to provide path to a character device; default is /dev/tpm0\n" + " use cancel-path to provide path to TPM's cancel sysfs entry; if\n" + " not provided it will be searched for in /sys/class/misc/tpm?/device\n", + QEMU_ARCH_ALL) +STEXI + +The general form of a TPM device option is: +@table @option + +@item -tpmdev @var{backend} ,id=@var{id} [,@var{options}] +@findex -tpmdev +Backend type must be: +@option{passthrough}. + +The specific backend type will determine the applicable options. +The @code{-tpmdev} option creates the TPM backend and requires a +@code{-device} option that specifies the TPM frontend interface model. + +Options to each backend are described below. + +Use 'help' to print all available TPM backend types. +@example +qemu -tpmdev help +@end example + +@item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path} + +(Linux-host only) Enable access to the host's TPM using the passthrough +driver. + +@option{path} specifies the path to the host's TPM device, i.e., on +a Linux host this would be @code{/dev/tpm0}. +@option{path} is optional and by default @code{/dev/tpm0} is used. + +@option{cancel-path} specifies the path to the host TPM device's sysfs +entry allowing for cancellation of an ongoing TPM command. +@option{cancel-path} is optional and by default QEMU will search for the +sysfs entry to use. + +Some notes about using the host's TPM with the passthrough driver: + +The TPM device accessed by the passthrough driver must not be +used by any other application on the host. + +Since the host's firmware (BIOS/UEFI) has already initialized the TPM, +the VM's firmware (BIOS/UEFI) will not be able to initialize the +TPM again and may therefore not show a TPM-specific menu that would +otherwise allow the user to configure the TPM, e.g., allow the user to +enable/disable or activate/deactivate the TPM. +Further, if TPM ownership is released from within a VM then the host's TPM +will get disabled and deactivated. To enable and activate the +TPM again afterwards, the host has to be rebooted and the user is +required to enter the firmware's menu to enable and activate the TPM. +If the TPM is left disabled and/or deactivated most TPM commands will fail. + +To create a passthrough TPM use the following two options: +@example +-tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0 +@end example +Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by +@code{tpmdev=tpm0} in the device option. + +@end table + +ETEXI + +DEFHEADING() + +#endif + +DEFHEADING(Linux/Multiboot boot specific:) +STEXI + +When using these options, you can use a given Linux or Multiboot +kernel without installing it in the disk image. It can be useful +for easier testing of various kernels. + +@table @option +ETEXI + +DEF("kernel", HAS_ARG, QEMU_OPTION_kernel, \ + "-kernel bzImage use 'bzImage' as kernel image\n", QEMU_ARCH_ALL) +STEXI +@item -kernel @var{bzImage} +@findex -kernel +Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel +or in multiboot format. +ETEXI + +DEF("append", HAS_ARG, QEMU_OPTION_append, \ + "-append cmdline use 'cmdline' as kernel command line\n", QEMU_ARCH_ALL) +STEXI +@item -append @var{cmdline} +@findex -append +Use @var{cmdline} as kernel command line +ETEXI + +DEF("initrd", HAS_ARG, QEMU_OPTION_initrd, \ + "-initrd file use 'file' as initial ram disk\n", QEMU_ARCH_ALL) +STEXI +@item -initrd @var{file} +@findex -initrd +Use @var{file} as initial ram disk. + +@item -initrd "@var{file1} arg=foo,@var{file2}" + +This syntax is only available with multiboot. + +Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the +first module. +ETEXI + +DEF("dtb", HAS_ARG, QEMU_OPTION_dtb, \ + "-dtb file use 'file' as device tree image\n", QEMU_ARCH_ALL) +STEXI +@item -dtb @var{file} +@findex -dtb +Use @var{file} as a device tree binary (dtb) image and pass it to the kernel +on boot. +ETEXI + +STEXI +@end table +ETEXI +DEFHEADING() + +DEFHEADING(Debug/Expert options:) +STEXI +@table @option +ETEXI + +DEF("fw_cfg", HAS_ARG, QEMU_OPTION_fwcfg, + "-fw_cfg [name=]<name>,file=<file>\n" + " add named fw_cfg entry from file\n", + QEMU_ARCH_ALL) +STEXI +@item -fw_cfg [name=]@var{name},file=@var{file} +@findex -fw_cfg +Add named fw_cfg entry from file. @var{name} determines the name of +the entry in the fw_cfg file directory exposed to the guest. +ETEXI + +DEF("serial", HAS_ARG, QEMU_OPTION_serial, \ + "-serial dev redirect the serial port to char device 'dev'\n", + QEMU_ARCH_ALL) +STEXI +@item -serial @var{dev} +@findex -serial +Redirect the virtual serial port to host character device +@var{dev}. The default device is @code{vc} in graphical mode and +@code{stdio} in non graphical mode. + +This option can be used several times to simulate up to 4 serial +ports. + +Use @code{-serial none} to disable all serial ports. + +Available character devices are: +@table @option +@item vc[:@var{W}x@var{H}] +Virtual console. Optionally, a width and height can be given in pixel with +@example +vc:800x600 +@end example +It is also possible to specify width or height in characters: +@example +vc:80Cx24C +@end example +@item pty +[Linux only] Pseudo TTY (a new PTY is automatically allocated) +@item none +No device is allocated. +@item null +void device +@item chardev:@var{id} +Use a named character device defined with the @code{-chardev} option. +@item /dev/XXX +[Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port +parameters are set according to the emulated ones. +@item /dev/parport@var{N} +[Linux only, parallel port only] Use host parallel port +@var{N}. Currently SPP and EPP parallel port features can be used. +@item file:@var{filename} +Write output to @var{filename}. No character can be read. +@item stdio +[Unix only] standard input/output +@item pipe:@var{filename} +name pipe @var{filename} +@item COM@var{n} +[Windows only] Use host serial port @var{n} +@item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}] +This implements UDP Net Console. +When @var{remote_host} or @var{src_ip} are not specified +they default to @code{0.0.0.0}. +When not using a specified @var{src_port} a random port is automatically chosen. + +If you just want a simple readonly console you can use @code{netcat} or +@code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as: +@code{nc -u -l -p 4555}. Any time QEMU writes something to that port it +will appear in the netconsole session. + +If you plan to send characters back via netconsole or you want to stop +and start QEMU a lot of times, you should have QEMU use the same +source port each time by using something like @code{-serial +udp::4555@@:4556} to QEMU. Another approach is to use a patched +version of netcat which can listen to a TCP port and send and receive +characters via udp. If you have a patched version of netcat which +activates telnet remote echo and single char transfer, then you can +use the following options to step up a netcat redirector to allow +telnet on port 5555 to access the QEMU port. +@table @code +@item QEMU Options: +-serial udp::4555@@:4556 +@item netcat options: +-u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T +@item telnet options: +localhost 5555 +@end table + +@item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}] +The TCP Net Console has two modes of operation. It can send the serial +I/O to a location or wait for a connection from a location. By default +the TCP Net Console is sent to @var{host} at the @var{port}. If you use +the @var{server} option QEMU will wait for a client socket application +to connect to the port before continuing, unless the @code{nowait} +option was specified. The @code{nodelay} option disables the Nagle buffering +algorithm. The @code{reconnect} option only applies if @var{noserver} is +set, if the connection goes down it will attempt to reconnect at the +given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only +one TCP connection at a time is accepted. You can use @code{telnet} to +connect to the corresponding character device. +@table @code +@item Example to send tcp console to 192.168.0.2 port 4444 +-serial tcp:192.168.0.2:4444 +@item Example to listen and wait on port 4444 for connection +-serial tcp::4444,server +@item Example to not wait and listen on ip 192.168.0.100 port 4444 +-serial tcp:192.168.0.100:4444,server,nowait +@end table + +@item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay] +The telnet protocol is used instead of raw tcp sockets. The options +work the same as if you had specified @code{-serial tcp}. The +difference is that the port acts like a telnet server or client using +telnet option negotiation. This will also allow you to send the +MAGIC_SYSRQ sequence if you use a telnet that supports sending the break +sequence. Typically in unix telnet you do it with Control-] and then +type "send break" followed by pressing the enter key. + +@item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}] +A unix domain socket is used instead of a tcp socket. The option works the +same as if you had specified @code{-serial tcp} except the unix domain socket +@var{path} is used for connections. + +@item mon:@var{dev_string} +This is a special option to allow the monitor to be multiplexed onto +another serial port. The monitor is accessed with key sequence of +@key{Control-a} and then pressing @key{c}. +@var{dev_string} should be any one of the serial devices specified +above. An example to multiplex the monitor onto a telnet server +listening on port 4444 would be: +@table @code +@item -serial mon:telnet::4444,server,nowait +@end table +When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate +QEMU any more but will be passed to the guest instead. + +@item braille +Braille device. This will use BrlAPI to display the braille output on a real +or fake device. + +@item msmouse +Three button serial mouse. Configure the guest to use Microsoft protocol. +@end table +ETEXI + +DEF("parallel", HAS_ARG, QEMU_OPTION_parallel, \ + "-parallel dev redirect the parallel port to char device 'dev'\n", + QEMU_ARCH_ALL) +STEXI +@item -parallel @var{dev} +@findex -parallel +Redirect the virtual parallel port to host device @var{dev} (same +devices as the serial port). On Linux hosts, @file{/dev/parportN} can +be used to use hardware devices connected on the corresponding host +parallel port. + +This option can be used several times to simulate up to 3 parallel +ports. + +Use @code{-parallel none} to disable all parallel ports. +ETEXI + +DEF("monitor", HAS_ARG, QEMU_OPTION_monitor, \ + "-monitor dev redirect the monitor to char device 'dev'\n", + QEMU_ARCH_ALL) +STEXI +@item -monitor @var{dev} +@findex -monitor +Redirect the monitor to host device @var{dev} (same devices as the +serial port). +The default device is @code{vc} in graphical mode and @code{stdio} in +non graphical mode. +Use @code{-monitor none} to disable the default monitor. +ETEXI +DEF("qmp", HAS_ARG, QEMU_OPTION_qmp, \ + "-qmp dev like -monitor but opens in 'control' mode\n", + QEMU_ARCH_ALL) +STEXI +@item -qmp @var{dev} +@findex -qmp +Like -monitor but opens in 'control' mode. +ETEXI +DEF("qmp-pretty", HAS_ARG, QEMU_OPTION_qmp_pretty, \ + "-qmp-pretty dev like -qmp but uses pretty JSON formatting\n", + QEMU_ARCH_ALL) +STEXI +@item -qmp-pretty @var{dev} +@findex -qmp-pretty +Like -qmp but uses pretty JSON formatting. +ETEXI + +DEF("mon", HAS_ARG, QEMU_OPTION_mon, \ + "-mon [chardev=]name[,mode=readline|control][,default]\n", QEMU_ARCH_ALL) +STEXI +@item -mon [chardev=]name[,mode=readline|control][,default] +@findex -mon +Setup monitor on chardev @var{name}. +ETEXI + +DEF("debugcon", HAS_ARG, QEMU_OPTION_debugcon, \ + "-debugcon dev redirect the debug console to char device 'dev'\n", + QEMU_ARCH_ALL) +STEXI +@item -debugcon @var{dev} +@findex -debugcon +Redirect the debug console to host device @var{dev} (same devices as the +serial port). The debug console is an I/O port which is typically port +0xe9; writing to that I/O port sends output to this device. +The default device is @code{vc} in graphical mode and @code{stdio} in +non graphical mode. +ETEXI + +DEF("pidfile", HAS_ARG, QEMU_OPTION_pidfile, \ + "-pidfile file write PID to 'file'\n", QEMU_ARCH_ALL) +STEXI +@item -pidfile @var{file} +@findex -pidfile +Store the QEMU process PID in @var{file}. It is useful if you launch QEMU +from a script. +ETEXI + +DEF("singlestep", 0, QEMU_OPTION_singlestep, \ + "-singlestep always run in singlestep mode\n", QEMU_ARCH_ALL) +STEXI +@item -singlestep +@findex -singlestep +Run the emulation in single step mode. +ETEXI + +DEF("S", 0, QEMU_OPTION_S, \ + "-S freeze CPU at startup (use 'c' to start execution)\n", + QEMU_ARCH_ALL) +STEXI +@item -S +@findex -S +Do not start CPU at startup (you must type 'c' in the monitor). +ETEXI + +DEF("realtime", HAS_ARG, QEMU_OPTION_realtime, + "-realtime [mlock=on|off]\n" + " run qemu with realtime features\n" + " mlock=on|off controls mlock support (default: on)\n", + QEMU_ARCH_ALL) +STEXI +@item -realtime mlock=on|off +@findex -realtime +Run qemu with realtime features. +mlocking qemu and guest memory can be enabled via @option{mlock=on} +(enabled by default). +ETEXI + +DEF("gdb", HAS_ARG, QEMU_OPTION_gdb, \ + "-gdb dev wait for gdb connection on 'dev'\n", QEMU_ARCH_ALL) +STEXI +@item -gdb @var{dev} +@findex -gdb +Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical +connections will likely be TCP-based, but also UDP, pseudo TTY, or even +stdio are reasonable use case. The latter is allowing to start QEMU from +within gdb and establish the connection via a pipe: +@example +(gdb) target remote | exec qemu-system-i386 -gdb stdio ... +@end example +ETEXI + +DEF("s", 0, QEMU_OPTION_s, \ + "-s shorthand for -gdb tcp::" DEFAULT_GDBSTUB_PORT "\n", + QEMU_ARCH_ALL) +STEXI +@item -s +@findex -s +Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234 +(@pxref{gdb_usage}). +ETEXI + +DEF("d", HAS_ARG, QEMU_OPTION_d, \ + "-d item1,... enable logging of specified items (use '-d help' for a list of log items)\n", + QEMU_ARCH_ALL) +STEXI +@item -d @var{item1}[,...] +@findex -d +Enable logging of specified items. Use '-d help' for a list of log items. +ETEXI + +DEF("D", HAS_ARG, QEMU_OPTION_D, \ + "-D logfile output log to logfile (default stderr)\n", + QEMU_ARCH_ALL) +STEXI +@item -D @var{logfile} +@findex -D +Output log in @var{logfile} instead of to stderr +ETEXI + +DEF("L", HAS_ARG, QEMU_OPTION_L, \ + "-L path set the directory for the BIOS, VGA BIOS and keymaps\n", + QEMU_ARCH_ALL) +STEXI +@item -L @var{path} +@findex -L +Set the directory for the BIOS, VGA BIOS and keymaps. +ETEXI + +DEF("bios", HAS_ARG, QEMU_OPTION_bios, \ + "-bios file set the filename for the BIOS\n", QEMU_ARCH_ALL) +STEXI +@item -bios @var{file} +@findex -bios +Set the filename for the BIOS. +ETEXI + +DEF("enable-kvm", 0, QEMU_OPTION_enable_kvm, \ + "-enable-kvm enable KVM full virtualization support\n", QEMU_ARCH_ALL) +STEXI +@item -enable-kvm +@findex -enable-kvm +Enable KVM full virtualization support. This option is only available +if KVM support is enabled when compiling. +ETEXI + +DEF("xen-domid", HAS_ARG, QEMU_OPTION_xen_domid, + "-xen-domid id specify xen guest domain id\n", QEMU_ARCH_ALL) +DEF("xen-create", 0, QEMU_OPTION_xen_create, + "-xen-create create domain using xen hypercalls, bypassing xend\n" + " warning: should not be used when xend is in use\n", + QEMU_ARCH_ALL) +DEF("xen-attach", 0, QEMU_OPTION_xen_attach, + "-xen-attach attach to existing xen domain\n" + " xend will use this when starting QEMU\n", + QEMU_ARCH_ALL) +STEXI +@item -xen-domid @var{id} +@findex -xen-domid +Specify xen guest domain @var{id} (XEN only). +@item -xen-create +@findex -xen-create +Create domain using xen hypercalls, bypassing xend. +Warning: should not be used when xend is in use (XEN only). +@item -xen-attach +@findex -xen-attach +Attach to existing xen domain. +xend will use this when starting QEMU (XEN only). +ETEXI + +DEF("no-reboot", 0, QEMU_OPTION_no_reboot, \ + "-no-reboot exit instead of rebooting\n", QEMU_ARCH_ALL) +STEXI +@item -no-reboot +@findex -no-reboot +Exit instead of rebooting. +ETEXI + +DEF("no-shutdown", 0, QEMU_OPTION_no_shutdown, \ + "-no-shutdown stop before shutdown\n", QEMU_ARCH_ALL) +STEXI +@item -no-shutdown +@findex -no-shutdown +Don't exit QEMU on guest shutdown, but instead only stop the emulation. +This allows for instance switching to monitor to commit changes to the +disk image. +ETEXI + +DEF("loadvm", HAS_ARG, QEMU_OPTION_loadvm, \ + "-loadvm [tag|id]\n" \ + " start right away with a saved state (loadvm in monitor)\n", + QEMU_ARCH_ALL) +STEXI +@item -loadvm @var{file} +@findex -loadvm +Start right away with a saved state (@code{loadvm} in monitor) +ETEXI + +#ifndef _WIN32 +DEF("daemonize", 0, QEMU_OPTION_daemonize, \ + "-daemonize daemonize QEMU after initializing\n", QEMU_ARCH_ALL) +#endif +STEXI +@item -daemonize +@findex -daemonize +Daemonize the QEMU process after initialization. QEMU will not detach from +standard IO until it is ready to receive connections on any of its devices. +This option is a useful way for external programs to launch QEMU without having +to cope with initialization race conditions. +ETEXI + +DEF("option-rom", HAS_ARG, QEMU_OPTION_option_rom, \ + "-option-rom rom load a file, rom, into the option ROM space\n", + QEMU_ARCH_ALL) +STEXI +@item -option-rom @var{file} +@findex -option-rom +Load the contents of @var{file} as an option ROM. +This option is useful to load things like EtherBoot. +ETEXI + +HXCOMM Silently ignored for compatibility +DEF("clock", HAS_ARG, QEMU_OPTION_clock, "", QEMU_ARCH_ALL) + +HXCOMM Options deprecated by -rtc +DEF("localtime", 0, QEMU_OPTION_localtime, "", QEMU_ARCH_ALL) +DEF("startdate", HAS_ARG, QEMU_OPTION_startdate, "", QEMU_ARCH_ALL) + +DEF("rtc", HAS_ARG, QEMU_OPTION_rtc, \ + "-rtc [base=utc|localtime|date][,clock=host|rt|vm][,driftfix=none|slew]\n" \ + " set the RTC base and clock, enable drift fix for clock ticks (x86 only)\n", + QEMU_ARCH_ALL) + +STEXI + +@item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew] +@findex -rtc +Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current +UTC or local time, respectively. @code{localtime} is required for correct date in +MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the +format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC. + +By default the RTC is driven by the host system time. This allows using of the +RTC as accurate reference clock inside the guest, specifically if the host +time is smoothly following an accurate external reference clock, e.g. via NTP. +If you want to isolate the guest time from the host, you can set @option{clock} +to @code{rt} instead. To even prevent it from progressing during suspension, +you can set it to @code{vm}. + +Enable @option{driftfix} (i386 targets only) if you experience time drift problems, +specifically with Windows' ACPI HAL. This option will try to figure out how +many timer interrupts were not processed by the Windows guest and will +re-inject them. +ETEXI + +DEF("icount", HAS_ARG, QEMU_OPTION_icount, \ + "-icount [shift=N|auto][,align=on|off][,sleep=no]\n" \ + " enable virtual instruction counter with 2^N clock ticks per\n" \ + " instruction, enable aligning the host and virtual clocks\n" \ + " or disable real time cpu sleeping\n", QEMU_ARCH_ALL) +STEXI +@item -icount [shift=@var{N}|auto] +@findex -icount +Enable virtual instruction counter. The virtual cpu will execute one +instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified +then the virtual cpu speed will be automatically adjusted to keep virtual +time within a few seconds of real time. + +When the virtual cpu is sleeping, the virtual time will advance at default +speed unless @option{sleep=no} is specified. +With @option{sleep=no}, the virtual time will jump to the next timer deadline +instantly whenever the virtual cpu goes to sleep mode and will not advance +if no timer is enabled. This behavior give deterministic execution times from +the guest point of view. + +Note that while this option can give deterministic behavior, it does not +provide cycle accurate emulation. Modern CPUs contain superscalar out of +order cores with complex cache hierarchies. The number of instructions +executed often has little or no correlation with actual performance. + +@option{align=on} will activate the delay algorithm which will try to +to synchronise the host clock and the virtual clock. The goal is to +have a guest running at the real frequency imposed by the shift option. +Whenever the guest clock is behind the host clock and if +@option{align=on} is specified then we print a message to the user +to inform about the delay. +Currently this option does not work when @option{shift} is @code{auto}. +Note: The sync algorithm will work for those shift values for which +the guest clock runs ahead of the host clock. Typically this happens +when the shift value is high (how high depends on the host machine). +ETEXI + +DEF("watchdog", HAS_ARG, QEMU_OPTION_watchdog, \ + "-watchdog model\n" \ + " enable virtual hardware watchdog [default=none]\n", + QEMU_ARCH_ALL) +STEXI +@item -watchdog @var{model} +@findex -watchdog +Create a virtual hardware watchdog device. Once enabled (by a guest +action), the watchdog must be periodically polled by an agent inside +the guest or else the guest will be restarted. Choose a model for +which your guest has drivers. + +The @var{model} is the model of hardware watchdog to emulate. Use +@code{-watchdog help} to list available hardware models. Only one +watchdog can be enabled for a guest. + +The following models may be available: +@table @option +@item ib700 +iBASE 700 is a very simple ISA watchdog with a single timer. +@item i6300esb +Intel 6300ESB I/O controller hub is a much more featureful PCI-based +dual-timer watchdog. +@item diag288 +A virtual watchdog for s390x backed by the diagnose 288 hypercall +(currently KVM only). +@end table +ETEXI + +DEF("watchdog-action", HAS_ARG, QEMU_OPTION_watchdog_action, \ + "-watchdog-action reset|shutdown|poweroff|pause|debug|none\n" \ + " action when watchdog fires [default=reset]\n", + QEMU_ARCH_ALL) +STEXI +@item -watchdog-action @var{action} +@findex -watchdog-action + +The @var{action} controls what QEMU will do when the watchdog timer +expires. +The default is +@code{reset} (forcefully reset the guest). +Other possible actions are: +@code{shutdown} (attempt to gracefully shutdown the guest), +@code{poweroff} (forcefully poweroff the guest), +@code{pause} (pause the guest), +@code{debug} (print a debug message and continue), or +@code{none} (do nothing). + +Note that the @code{shutdown} action requires that the guest responds +to ACPI signals, which it may not be able to do in the sort of +situations where the watchdog would have expired, and thus +@code{-watchdog-action shutdown} is not recommended for production use. + +Examples: + +@table @code +@item -watchdog i6300esb -watchdog-action pause +@itemx -watchdog ib700 +@end table +ETEXI + +DEF("echr", HAS_ARG, QEMU_OPTION_echr, \ + "-echr chr set terminal escape character instead of ctrl-a\n", + QEMU_ARCH_ALL) +STEXI + +@item -echr @var{numeric_ascii_value} +@findex -echr +Change the escape character used for switching to the monitor when using +monitor and serial sharing. The default is @code{0x01} when using the +@code{-nographic} option. @code{0x01} is equal to pressing +@code{Control-a}. You can select a different character from the ascii +control keys where 1 through 26 map to Control-a through Control-z. For +instance you could use the either of the following to change the escape +character to Control-t. +@table @code +@item -echr 0x14 +@itemx -echr 20 +@end table +ETEXI + +DEF("virtioconsole", HAS_ARG, QEMU_OPTION_virtiocon, \ + "-virtioconsole c\n" \ + " set virtio console\n", QEMU_ARCH_ALL) +STEXI +@item -virtioconsole @var{c} +@findex -virtioconsole +Set virtio console. + +This option is maintained for backward compatibility. + +Please use @code{-device virtconsole} for the new way of invocation. +ETEXI + +DEF("show-cursor", 0, QEMU_OPTION_show_cursor, \ + "-show-cursor show cursor\n", QEMU_ARCH_ALL) +STEXI +@item -show-cursor +@findex -show-cursor +Show cursor. +ETEXI + +DEF("tb-size", HAS_ARG, QEMU_OPTION_tb_size, \ + "-tb-size n set TB size\n", QEMU_ARCH_ALL) +STEXI +@item -tb-size @var{n} +@findex -tb-size +Set TB size. +ETEXI + +DEF("incoming", HAS_ARG, QEMU_OPTION_incoming, \ + "-incoming tcp:[host]:port[,to=maxport][,ipv4][,ipv6]\n" \ + "-incoming rdma:host:port[,ipv4][,ipv6]\n" \ + "-incoming unix:socketpath\n" \ + " prepare for incoming migration, listen on\n" \ + " specified protocol and socket address\n" \ + "-incoming fd:fd\n" \ + "-incoming exec:cmdline\n" \ + " accept incoming migration on given file descriptor\n" \ + " or from given external command\n" \ + "-incoming defer\n" \ + " wait for the URI to be specified via migrate_incoming\n", + QEMU_ARCH_ALL) +STEXI +@item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6] +@itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6] +@findex -incoming +Prepare for incoming migration, listen on a given tcp port. + +@item -incoming unix:@var{socketpath} +Prepare for incoming migration, listen on a given unix socket. + +@item -incoming fd:@var{fd} +Accept incoming migration from a given filedescriptor. + +@item -incoming exec:@var{cmdline} +Accept incoming migration as an output from specified external command. + +@item -incoming defer +Wait for the URI to be specified via migrate_incoming. The monitor can +be used to change settings (such as migration parameters) prior to issuing +the migrate_incoming to allow the migration to begin. +ETEXI + +DEF("nodefaults", 0, QEMU_OPTION_nodefaults, \ + "-nodefaults don't create default devices\n", QEMU_ARCH_ALL) +STEXI +@item -nodefaults +@findex -nodefaults +Don't create default devices. Normally, QEMU sets the default devices like serial +port, parallel port, virtual console, monitor device, VGA adapter, floppy and +CD-ROM drive and others. The @code{-nodefaults} option will disable all those +default devices. +ETEXI + +#ifndef _WIN32 +DEF("chroot", HAS_ARG, QEMU_OPTION_chroot, \ + "-chroot dir chroot to dir just before starting the VM\n", + QEMU_ARCH_ALL) +#endif +STEXI +@item -chroot @var{dir} +@findex -chroot +Immediately before starting guest execution, chroot to the specified +directory. Especially useful in combination with -runas. +ETEXI + +#ifndef _WIN32 +DEF("runas", HAS_ARG, QEMU_OPTION_runas, \ + "-runas user change to user id user just before starting the VM\n", + QEMU_ARCH_ALL) +#endif +STEXI +@item -runas @var{user} +@findex -runas +Immediately before starting guest execution, drop root privileges, switching +to the specified user. +ETEXI + +DEF("prom-env", HAS_ARG, QEMU_OPTION_prom_env, + "-prom-env variable=value\n" + " set OpenBIOS nvram variables\n", + QEMU_ARCH_PPC | QEMU_ARCH_SPARC) +STEXI +@item -prom-env @var{variable}=@var{value} +@findex -prom-env +Set OpenBIOS nvram @var{variable} to given @var{value} (PPC, SPARC only). +ETEXI +DEF("semihosting", 0, QEMU_OPTION_semihosting, + "-semihosting semihosting mode\n", + QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | + QEMU_ARCH_MIPS) +STEXI +@item -semihosting +@findex -semihosting +Enable semihosting mode (ARM, M68K, Xtensa, MIPS only). +ETEXI +DEF("semihosting-config", HAS_ARG, QEMU_OPTION_semihosting_config, + "-semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]]\n" \ + " semihosting configuration\n", +QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 | +QEMU_ARCH_MIPS) +STEXI +@item -semihosting-config [enable=on|off][,target=native|gdb|auto][,arg=str[,...]] +@findex -semihosting-config +Enable and configure semihosting (ARM, M68K, Xtensa, MIPS only). +@table @option +@item target=@code{native|gdb|auto} +Defines where the semihosting calls will be addressed, to QEMU (@code{native}) +or to GDB (@code{gdb}). The default is @code{auto}, which means @code{gdb} +during debug sessions and @code{native} otherwise. +@item arg=@var{str1},arg=@var{str2},... +Allows the user to pass input arguments, and can be used multiple times to build +up a list. The old-style @code{-kernel}/@code{-append} method of passing a +command line is still supported for backward compatibility. If both the +@code{--semihosting-config arg} and the @code{-kernel}/@code{-append} are +specified, the former is passed to semihosting as it always takes precedence. +@end table +ETEXI +DEF("old-param", 0, QEMU_OPTION_old_param, + "-old-param old param mode\n", QEMU_ARCH_ARM) +STEXI +@item -old-param +@findex -old-param (ARM) +Old param mode (ARM only). +ETEXI + +DEF("sandbox", HAS_ARG, QEMU_OPTION_sandbox, \ + "-sandbox <arg> Enable seccomp mode 2 system call filter (default 'off').\n", + QEMU_ARCH_ALL) +STEXI +@item -sandbox @var{arg} +@findex -sandbox +Enable Seccomp mode 2 system call filter. 'on' will enable syscall filtering and 'off' will +disable it. The default is 'off'. +ETEXI + +DEF("readconfig", HAS_ARG, QEMU_OPTION_readconfig, + "-readconfig <file>\n", QEMU_ARCH_ALL) +STEXI +@item -readconfig @var{file} +@findex -readconfig +Read device configuration from @var{file}. This approach is useful when you want to spawn +QEMU process with many command line options but you don't want to exceed the command line +character limit. +ETEXI +DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig, + "-writeconfig <file>\n" + " read/write config file\n", QEMU_ARCH_ALL) +STEXI +@item -writeconfig @var{file} +@findex -writeconfig +Write device configuration to @var{file}. The @var{file} can be either filename to save +command line and device configuration into file or dash @code{-}) character to print the +output to stdout. This can be later used as input file for @code{-readconfig} option. +ETEXI +DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig, + "-nodefconfig\n" + " do not load default config files at startup\n", + QEMU_ARCH_ALL) +STEXI +@item -nodefconfig +@findex -nodefconfig +Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup. +The @code{-nodefconfig} option will prevent QEMU from loading any of those config files. +ETEXI +DEF("no-user-config", 0, QEMU_OPTION_nouserconfig, + "-no-user-config\n" + " do not load user-provided config files at startup\n", + QEMU_ARCH_ALL) +STEXI +@item -no-user-config +@findex -no-user-config +The @code{-no-user-config} option makes QEMU not load any of the user-provided +config files on @var{sysconfdir}, but won't make it skip the QEMU-provided config +files from @var{datadir}. +ETEXI +DEF("trace", HAS_ARG, QEMU_OPTION_trace, + "-trace [events=<file>][,file=<file>]\n" + " specify tracing options\n", + QEMU_ARCH_ALL) +STEXI +HXCOMM This line is not accurate, as some sub-options are backend-specific but +HXCOMM HX does not support conditional compilation of text. +@item -trace [events=@var{file}][,file=@var{file}] +@findex -trace + +Specify tracing options. + +@table @option +@item events=@var{file} +Immediately enable events listed in @var{file}. +The file must contain one event name (as listed in the @var{trace-events} file) +per line. +This option is only available if QEMU has been compiled with +either @var{simple} or @var{stderr} tracing backend. +@item file=@var{file} +Log output traces to @var{file}. + +This option is only available if QEMU has been compiled with +the @var{simple} tracing backend. +@end table +ETEXI + +HXCOMM Internal use +DEF("qtest", HAS_ARG, QEMU_OPTION_qtest, "", QEMU_ARCH_ALL) +DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log, "", QEMU_ARCH_ALL) + +#ifdef __linux__ +DEF("enable-fips", 0, QEMU_OPTION_enablefips, + "-enable-fips enable FIPS 140-2 compliance\n", + QEMU_ARCH_ALL) +#endif +STEXI +@item -enable-fips +@findex -enable-fips +Enable FIPS 140-2 compliance mode. +ETEXI + +HXCOMM Deprecated by -machine accel=tcg property +DEF("no-kvm", 0, QEMU_OPTION_no_kvm, "", QEMU_ARCH_I386) + +HXCOMM Deprecated by kvm-pit driver properties +DEF("no-kvm-pit-reinjection", 0, QEMU_OPTION_no_kvm_pit_reinjection, + "", QEMU_ARCH_I386) + +HXCOMM Deprecated (ignored) +DEF("no-kvm-pit", 0, QEMU_OPTION_no_kvm_pit, "", QEMU_ARCH_I386) + +HXCOMM Deprecated by -machine kernel_irqchip=on|off property +DEF("no-kvm-irqchip", 0, QEMU_OPTION_no_kvm_irqchip, "", QEMU_ARCH_I386) + +HXCOMM Deprecated (ignored) +DEF("tdf", 0, QEMU_OPTION_tdf,"", QEMU_ARCH_ALL) + +DEF("msg", HAS_ARG, QEMU_OPTION_msg, + "-msg timestamp[=on|off]\n" + " change the format of messages\n" + " on|off controls leading timestamps (default:on)\n", + QEMU_ARCH_ALL) +STEXI +@item -msg timestamp[=on|off] +@findex -msg +prepend a timestamp to each log message.(default:on) +ETEXI + +DEF("dump-vmstate", HAS_ARG, QEMU_OPTION_dump_vmstate, + "-dump-vmstate <file>\n" + " Output vmstate information in JSON format to file.\n" + " Use the scripts/vmstate-static-checker.py file to\n" + " check for possible regressions in migration code\n" + " by comparing two such vmstate dumps.", + QEMU_ARCH_ALL) +STEXI +@item -dump-vmstate @var{file} +@findex -dump-vmstate +Dump json-encoded vmstate information for current machine type to file +in @var{file} +ETEXI + +DEFHEADING(Generic object creation) + +DEF("object", HAS_ARG, QEMU_OPTION_object, + "-object TYPENAME[,PROP1=VALUE1,...]\n" + " create a new object of type TYPENAME setting properties\n" + " in the order they are specified. Note that the 'id'\n" + " property must be set. These objects are placed in the\n" + " '/objects' path.\n", + QEMU_ARCH_ALL) +STEXI +@item -object @var{typename}[,@var{prop1}=@var{value1},...] +@findex -object +Create a new object of type @var{typename} setting properties +in the order they are specified. Note that the 'id' +property must be set. These objects are placed in the +'/objects' path. + +@table @option + +@item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off} + +Creates a memory file backend object, which can be used to back +the guest RAM with huge pages. The @option{id} parameter is a +unique ID that will be used to reference this memory region +when configuring the @option{-numa} argument. The @option{size} +option provides the size of the memory region, and accepts +common suffixes, eg @option{500M}. The @option{mem-path} provides +the path to either a shared memory or huge page filesystem mount. +The @option{share} boolean option determines whether the memory +region is marked as private to QEMU, or shared. The latter allows +a co-operating external process to access the QEMU memory region. + +@item -object rng-random,id=@var{id},filename=@var{/dev/random} + +Creates a random number generator backend which obtains entropy from +a device on the host. The @option{id} parameter is a unique ID that +will be used to reference this entropy backend from the @option{virtio-rng} +device. The @option{filename} parameter specifies which file to obtain +entropy from and if omitted defaults to @option{/dev/random}. + +@item -object rng-egd,id=@var{id},chardev=@var{chardevid} + +Creates a random number generator backend which obtains entropy from +an external daemon running on the host. The @option{id} parameter is +a unique ID that will be used to reference this entropy backend from +the @option{virtio-rng} device. The @option{chardev} parameter is +the unique ID of a character device backend that provides the connection +to the RNG daemon. + +@end table + +ETEXI + + +HXCOMM This is the last statement. Insert new options before this line! +STEXI +@end table +ETEXI |