| blob | 2f0465eeb1d10254a4ee035ea258652da9440601 |
2 HXCOMM Text between STEXI and ETEXI are copied to texi version and
3 HXCOMM discarded from C version
6 HXCOMM architectures.
10 STEXI
11 @table @option
12 ETEXI
16 STEXI
17 @item -h
18 @findex -h
19 Display help and exit
20 ETEXI
24 STEXI
25 @item -version
26 @findex -version
27 Display version information and exit
28 ETEXI
47 QEMU_ARCH_ALL)
48 STEXI
50 @findex -machine
53 @table @option
58 to initialize.
59 @item kernel_irqchip=on|off
61 @item gfx_passthru=on|off
63 @item vmport=on|off|auto
66 is on.
67 @item kvm_shadow_mem=size
68 Defines the size of the KVM shadow MMU.
75 @item iommu=on|off
79 controls whether AES wrapping keys will be created to allow
83 controls whether DEA wrapping keys will be created to allow
85 @item nvdimm=on|off
87 @end table
88 ETEXI
90 HXCOMM Deprecated by -machine
95 STEXI
97 @findex -cpu
99 ETEXI
109 QEMU_ARCH_ALL)
110 STEXI
111 @item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
112 @findex -smp
120 specifies the maximum number of hotpluggable CPUs.
121 ETEXI
126 STEXI
129 @findex -numa
133 resources. That is, it just assigns existing resources to NUMA nodes. This
134 means that one still has to use the @option{-m}, @option{-smp} options
135 to allocate RAM and VCPUs respectively, and possibly @option{-object}
136 to specify the memory backend for the @samp{memdev} suboption.
138 @samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, if one
139 node uses @samp{memdev}, all of them have to use it.
140 ETEXI
142 DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
145 STEXI
146 @item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}]
147 @findex -add-fd
149 Add a file descriptor to an fd set. Valid options are:
151 @table @option
152 @item fd=@var{fd}
153 This option defines the file descriptor of which a duplicate is added to fd set.
154 The file descriptor cannot be stdin, stdout, or stderr.
155 @item set=@var{set}
156 This option defines the ID of the fd set to add the file descriptor to.
157 @item opaque=@var{opaque}
158 This option defines a free-form string that can be used to describe @var{fd}.
159 @end table
161 You can open an image using pre-opened file descriptors from an fd set:
162 @example
163 qemu-system-i386
164 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
165 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
166 -drive file=/dev/fdset/2,index=0,media=disk
167 @end example
168 ETEXI
170 DEF("set", HAS_ARG, QEMU_OPTION_set,
174 STEXI
175 @item -set @var{group}.@var{id}.@var{arg}=@var{value}
176 @findex -set
178 ETEXI
180 DEF("global", HAS_ARG, QEMU_OPTION_global,
184 QEMU_ARCH_ALL)
185 STEXI
186 @item -global @var{driver}.@var{prop}=@var{value}
187 @itemx -global driver=@var{driver},property=@var{property},value=@var{value}
188 @findex -global
191 @example
192 qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk
193 @end example
196 created automatically by the machine model. To create a device which is not
202 ETEXI
211 QEMU_ARCH_ALL)
212 STEXI
213 @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]
214 @findex -boot
219 particular boot order only on the first startup, specify it via
235 system support it.
238 supports it. This only effects when boot priority is changed by
241 @example
248 @end example
251 use is discouraged as it may be removed from future versions.
252 ETEXI
261 QEMU_ARCH_ALL)
262 STEXI
264 @findex -m
268 could be used to set amount of hotpluggable memory slots and maximum amount of
275 @example
277 @end example
280 be enabled and the guest startup RAM will never increase.
281 ETEXI
283 DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
285 STEXI
286 @item -mem-path @var{path}
287 @findex -mem-path
288 Allocate guest RAM from a temporarily created file in @var{path}.
289 ETEXI
291 DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
293 QEMU_ARCH_ALL)
294 STEXI
295 @item -mem-prealloc
296 @findex -mem-prealloc
297 Preallocate memory when using -mem-path.
298 ETEXI
300 DEF("k", HAS_ARG, QEMU_OPTION_k,
302 QEMU_ARCH_ALL)
303 STEXI
304 @item -k @var{language}
305 @findex -k
306 Use keyboard layout @var{language} (for example @code{fr} for
307 French). This option is only needed where it is not easy to get raw PC
308 keycodes (e.g. on Macs, with some X11 servers or with a VNC
310 hosts.
312 The available layouts are:
313 @example
317 @end example
320 ETEXI
325 QEMU_ARCH_ALL)
326 STEXI
330 parameters.
331 ETEXI
338 STEXI
340 @findex -soundhw
342 available sound hardware.
344 @example
351 @end example
353 Note that Linux's i810_audio OSS kernel (for AC97) module might
354 require manually specifying clocking.
356 @example
357 modprobe i810_audio clocking=48000
358 @end example
359 ETEXI
361 DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
365 STEXI
366 @item -balloon none
367 @findex -balloon
368 Disable balloon device.
369 @item -balloon virtio[,addr=@var{addr}]
370 Enable virtio balloon device (default), optionally with PCI address
371 @var{addr}.
372 ETEXI
374 DEF("device", HAS_ARG, QEMU_OPTION_device,
380 QEMU_ARCH_ALL)
381 STEXI
382 @item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
383 @findex -device
384 Add device @var{driver}. @var{prop}=@var{value} sets driver
385 properties. Valid properties depend on the driver. To get help on
386 possible drivers and properties, use @code{-device help} and
387 @code{-device @var{driver},help}.
389 Some drivers are:
390 @item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}]
392 Add an IPMI BMC. This is a simulation of a hardware management
393 interface processor that normally sits on a system. It provides
394 a watchdog and the ability to reset and power control the system.
395 You need to connect this to an IPMI interface to make it useful
397 The IPMI slave address to use for the BMC. The default is 0x20.
398 This address is the BMC's address on the I2C network of management
400 it.
402 @item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}]
404 Add a connection to an external IPMI BMC simulator. Instead of
405 locally emulating the BMC like the above item, instead connect
406 to an external entity that provides the IPMI services.
408 A connection is made to an external BMC simulator. If you do this, it
409 is strongly recommended that you use the "reconnect=" chardev option
410 to reconnect to the simulator if the connection is lost. Note that if
411 this is not used carefully, it can be a security issue, as the
412 interface has the ability to send resets, NMIs, and power off the VM.
414 on a secure port on localhost, so neither the simulator nor QEMU is
415 exposed to any outside network.
422 Add a KCS IPMI interafce on the ISA bus. This also adds a
425 @table @option
433 @end table
440 ETEXI
448 QEMU_ARCH_ALL)
449 STEXI
451 @findex -name
456 Naming of individual threads can also be enabled on Linux to aid debugging.
457 ETEXI
462 STEXI
464 @findex -uuid
465 Set system UUID.
466 ETEXI
468 STEXI
469 @end table
470 ETEXI
474 STEXI
475 @table @option
476 ETEXI
481 STEXI
484 @findex -fda
485 @findex -fdb
487 ETEXI
495 STEXI
500 @findex -hda
501 @findex -hdb
502 @findex -hdc
503 @findex -hdd
505 ETEXI
509 QEMU_ARCH_ALL)
510 STEXI
512 @findex -cdrom
516 ETEXI
533 STEXI
535 @findex -drive
539 @table @option
545 Special files such as iSCSI devices can be specified using protocol
551 These options define where is connected the drive by defining the bus number and
552 the unit id.
564 @var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data.
566 @var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
568 @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.
572 an untrusted format header.
574 This option specifies the serial number to assign to the device.
576 Specify the controller's PCI address (if=virtio only).
577 @item werror=@var{action},rerror=@var{action}
578 Specify which @var{action} to take on write and read errors. Valid actions are:
579 "ignore" (ignore the error and try to continue), "stop" (pause QEMU),
580 "report" (report the error to the guest), "enospc" (pause QEMU only if the
581 host disk is full; report the error to the guest otherwise).
582 The default setting is @option{werror=enospc} and @option{rerror=report}.
583 @item readonly
584 Open drive @option{file} as read-only. Guest write attempts will fail.
585 @item copy-on-read=@var{copy-on-read}
586 @var{copy-on-read} is "on" or "off" and enables whether to copy read backing
587 file sectors into the image file.
588 @item detect-zeroes=@var{detect-zeroes}
589 @var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic
590 conversion of plain zero writes by the OS to driver specific optimized
591 zero write commands. You may even choose "unmap" if @var{discard} is set
592 to "unmap" to allow a zero write to be converted to an UNMAP operation.
593 @end table
595 By default, the @option{cache=writeback} mode is used. It will report data
596 writes as completed as soon as the data is present in the host page cache.
597 This is safe as long as your guest OS makes sure to correctly flush disk caches
598 where needed. If your guest OS does not handle volatile disk write caches
599 correctly and your host crashes or loses power, then the guest may experience
600 data corruption.
602 For such guests, you should consider using @option{cache=writethrough}. This
603 means that the host page cache will be used to read and write data, but write
604 notification will be sent to the guest only after QEMU has made sure to flush
605 each write to the disk. Be aware that this has a major impact on performance.
607 The host page cache can be avoided entirely with @option{cache=none}. This will
610 the guest OS must handle the disk write cache correctly in order to avoid data
611 corruption on host crashes.
613 The host page cache can be avoided while only sending write notifications to
614 the guest when the data has been flushed to the disk using
618 @option{cache=unsafe}. This option tells QEMU that it never needs to write any
619 data to the disk but can instead keep things in cache. If anything goes wrong,
620 like your host losing power, the disk storage getting disconnected accidentally,
621 etc. your image will most probably be rendered unusable. When using
622 the @option{-snapshot} option, unsafe caching is always used.
624 Copy-on-read avoids accessing the same backing file sectors repeatedly and is
625 useful when the backing file is over a slow network. By default copy-on-read
626 is off.
628 Instead of @option{-cdrom} you can use:
629 @example
630 qemu-system-i386 -drive file=file,index=2,media=cdrom
631 @end example
633 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
634 use:
635 @example
636 qemu-system-i386 -drive file=file,index=0,media=disk
637 qemu-system-i386 -drive file=file,index=1,media=disk
638 qemu-system-i386 -drive file=file,index=2,media=disk
639 qemu-system-i386 -drive file=file,index=3,media=disk
640 @end example
642 You can open an image using pre-opened file descriptors from an fd set:
643 @example
644 qemu-system-i386
645 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
646 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
647 -drive file=/dev/fdset/2,index=0,media=disk
648 @end example
650 You can connect a CDROM to the slave of ide0:
651 @example
652 qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
653 @end example
656 @example
658 @end example
661 @example
663 @end example
666 @example
669 @end example
672 incremented:
673 @example
675 @end example
676 is interpreted like:
677 @example
678 qemu-system-i386 -hda a -hdb b
679 @end example
680 ETEXI
684 QEMU_ARCH_ALL)
685 STEXI
686 @item -mtdblock @var{file}
687 @findex -mtdblock
688 Use @var{file} as on-board Flash memory image.
689 ETEXI
693 STEXI
694 @item -sd @var{file}
695 @findex -sd
696 Use @var{file} as SecureDigital card image.
697 ETEXI
701 STEXI
702 @item -pflash @var{file}
703 @findex -pflash
704 Use @var{file} as a parallel flash image.
705 ETEXI
709 QEMU_ARCH_ALL)
710 STEXI
711 @item -snapshot
712 @findex -snapshot
713 Write to temporary files instead of disk image files. In this case,
714 the raw disk image you use is not written back. You can however force
715 the write back by pressing @key{C-a s} (@pxref{disk_images}).
716 ETEXI
722 QEMU_ARCH_ALL)
723 STEXI
724 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
725 @findex -hdachs
726 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
727 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
728 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
729 all those parameters. This option is useful for old MS-DOS disk
730 images.
731 ETEXI
734 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
736 QEMU_ARCH_ALL)
738 STEXI
740 @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}]
741 @findex -fsdev
742 Define a new file system device. Valid options are:
743 @table @option
744 @item @var{fsdriver}
745 This option specifies the fs driver backend to use.
747 @item id=@var{id}
748 Specifies identifier for this device
749 @item path=@var{path}
750 Specifies the export path for the file system device. Files under
751 this path will be available to the 9p client on the guest.
752 @item security_model=@var{security_model}
753 Specifies the security model to be used for this export path.
756 credentials as they are created on the guest. This requires QEMU
758 attributes like uid, gid, mode bits and link target are stored as
760 hidden .virtfs_metadata directory. Directories exported by this security model cannot
762 passthrough except the sever won't report failures if it fails to
763 set file attributes like ownership. Security model is mandatory
764 only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
765 security model as a parameter.
766 @item writeout=@var{writeout}
768 This means that host page cache will be used to read and write data but
769 write notification will be sent to the guest only when the data has been
770 reported as written by the storage subsystem.
771 @item readonly
772 Enables exporting 9p share as a readonly mount for guests. By default
773 read-write access is given.
774 @item socket=@var{socket}
775 Enables proxy filesystem driver to use passed socket file for communicating
776 with virtfs-proxy-helper
777 @item sock_fd=@var{sock_fd}
778 Enables proxy filesystem driver to use passed socket descriptor for
779 communicating with virtfs-proxy-helper. Usually a helper like libvirt
780 will create socketpair and pass one of the fds as sock_fd
781 @end table
784 @item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
785 Options for virtio-9p-pci driver are:
786 @table @option
787 @item fsdev=@var{id}
788 Specifies the id value specified along with -fsdev option
789 @item mount_tag=@var{mount_tag}
790 Specifies the tag name to be used by the guest to mount this export point
791 @end table
793 ETEXI
796 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
798 QEMU_ARCH_ALL)
800 STEXI
802 @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}]
803 @findex -virtfs
805 The general form of a Virtual File system pass-through options are:
806 @table @option
807 @item @var{fsdriver}
808 This option specifies the fs driver backend to use.
810 @item id=@var{id}
811 Specifies identifier for this device
812 @item path=@var{path}
813 Specifies the export path for the file system device. Files under
814 this path will be available to the 9p client on the guest.
815 @item security_model=@var{security_model}
816 Specifies the security model to be used for this export path.
819 credentials as they are created on the guest. This requires QEMU
821 attributes like uid, gid, mode bits and link target are stored as
823 hidden .virtfs_metadata directory. Directories exported by this security model cannot
825 passthrough except the sever won't report failures if it fails to
826 set file attributes like ownership. Security model is mandatory only
827 for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
828 model as a parameter.
829 @item writeout=@var{writeout}
831 This means that host page cache will be used to read and write data but
832 write notification will be sent to the guest only when the data has been
833 reported as written by the storage subsystem.
834 @item readonly
835 Enables exporting 9p share as a readonly mount for guests. By default
836 read-write access is given.
837 @item socket=@var{socket}
838 Enables proxy filesystem driver to use passed socket file for
839 communicating with virtfs-proxy-helper. Usually a helper like libvirt
840 will create socketpair and pass one of the fds as sock_fd
841 @item sock_fd
842 Enables proxy filesystem driver to use passed 'sock_fd' as the socket
843 descriptor for interfacing with virtfs-proxy-helper
844 @end table
845 ETEXI
849 QEMU_ARCH_ALL)
850 STEXI
851 @item -virtfs_synth
852 @findex -virtfs_synth
853 Create synthetic file system image
854 ETEXI
856 STEXI
857 @end table
858 ETEXI
859 DEFHEADING()
861 DEFHEADING(USB options:)
862 STEXI
863 @table @option
864 ETEXI
868 QEMU_ARCH_ALL)
869 STEXI
870 @item -usb
871 @findex -usb
872 Enable the USB driver (will be the default soon)
873 ETEXI
877 QEMU_ARCH_ALL)
878 STEXI
880 @item -usbdevice @var{devname}
881 @findex -usbdevice
882 Add the USB device @var{devname}. @xref{usb_devices}.
884 @table @option
886 @item mouse
887 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
889 @item tablet
890 Pointer device that uses absolute coordinates (like a touchscreen). This
891 means QEMU is able to report the mouse position without having to grab the
892 mouse. Also overrides the PS/2 mouse emulation when activated.
894 @item disk:[format=@var{format}]:@var{file}
895 Mass storage device based on file. The optional @var{format} argument
896 will be used rather than detecting the format. Can be used to specifiy
897 @code{format=raw} to avoid interpreting an untrusted format header.
899 @item host:@var{bus}.@var{addr}
900 Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
902 @item host:@var{vendor_id}:@var{product_id}
903 Pass through the host device identified by @var{vendor_id}:@var{product_id}
904 (Linux only).
906 @item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
907 Serial converter to host character device @var{dev}, see @code{-serial} for the
908 available devices.
910 @item braille
911 Braille device. This will use BrlAPI to display the braille output on a real
912 or fake device.
914 @item net:@var{options}
915 Network adapter that supports CDC ethernet and RNDIS protocols.
917 @end table
918 ETEXI
920 STEXI
921 @end table
922 ETEXI
923 DEFHEADING()
925 DEFHEADING(Display options:)
926 STEXI
927 @table @option
928 ETEXI
936 STEXI
937 @item -display @var{type}
938 @findex -display
939 Select type of display to use. This option is a replacement for the
940 old style -sdl/-curses/... options. Valid values for @var{type} are
941 @table @option
942 @item sdl
943 Display video output via SDL (usually in a separate graphics
944 window; see the SDL documentation for other possibilities).
945 @item curses
946 Display video output via curses. For graphics device models which
947 support a text mode, QEMU can display this output using a
948 curses/ncurses interface. Nothing is displayed when the graphics
949 device is in graphical mode or if the graphics device does not support
950 a text mode. Generally only the VGA device models support text mode.
951 @item none
952 Do not display video output. The guest will still see an emulated
953 graphics card, but its output will not be displayed to the QEMU
954 user. This option differs from the -nographic option in that it
955 only affects what is done with video output; -nographic also changes
956 the destination of the serial and parallel port data.
957 @item gtk
958 Display video output in a GTK window. This interface provides drop-down
959 menus and other UI elements to configure and control the VM during
960 runtime.
961 @item vnc
962 Start a VNC server on display <arg>
963 @end table
964 ETEXI
968 QEMU_ARCH_ALL)
969 STEXI
970 @item -nographic
971 @findex -nographic
972 Normally, QEMU uses SDL to display the VGA output. With this option,
973 you can totally disable graphical output so that QEMU is a simple
974 command line application. The emulated serial port is redirected on
975 the console and muxed with the monitor (unless redirected elsewhere
976 explicitly). Therefore, you can still use QEMU to debug a Linux kernel
977 with a serial console. Use @key{C-a h} for help on switching between
978 the console and monitor.
979 ETEXI
983 QEMU_ARCH_ALL)
984 STEXI
985 @item -curses
986 @findex -curses
987 Normally, QEMU uses SDL to display the VGA output. With this option,
988 QEMU can display the VGA output when in text mode using a
989 curses/ncurses interface. Nothing is displayed in graphical mode.
990 ETEXI
994 QEMU_ARCH_ALL)
995 STEXI
996 @item -no-frame
997 @findex -no-frame
998 Do not use decorations for SDL windows and start them using the whole
999 available screen space. This makes the using QEMU in a dedicated desktop
1000 workspace more convenient.
1001 ETEXI
1005 QEMU_ARCH_ALL)
1006 STEXI
1007 @item -alt-grab
1008 @findex -alt-grab
1009 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
1010 affects the special keys (for fullscreen, monitor-mode switching, etc).
1011 ETEXI
1015 QEMU_ARCH_ALL)
1016 STEXI
1017 @item -ctrl-grab
1018 @findex -ctrl-grab
1019 Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
1020 affects the special keys (for fullscreen, monitor-mode switching, etc).
1021 ETEXI
1025 STEXI
1026 @item -no-quit
1027 @findex -no-quit
1028 Disable SDL window close capability.
1029 ETEXI
1033 STEXI
1034 @item -sdl
1035 @findex -sdl
1036 Enable SDL.
1037 ETEXI
1056 QEMU_ARCH_ALL)
1057 STEXI
1058 @item -spice @var{option}[,@var{option}[,...]]
1059 @findex -spice
1060 Enable the spice remote desktop protocol. Valid options are
1062 @table @option
1064 @item port=<nr>
1065 Set the TCP port spice is listening on for plaintext channels.
1067 @item addr=<addr>
1068 Set the IP address spice is listening on. Default is any address.
1070 @item ipv4
1071 @itemx ipv6
1072 @itemx unix
1073 Force using the specified IP version.
1075 @item password=<secret>
1076 Set the password you need to authenticate.
1078 @item sasl
1079 Require that the client use SASL to authenticate with the spice.
1080 The exact choice of authentication method used is controlled from the
1081 system / user's SASL configuration file for the 'qemu' service. This
1082 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1083 unprivileged user, an environment variable SASL_CONF_PATH can be used
1084 to make it search alternate locations for the service config.
1085 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1086 it is recommended that SASL always be combined with the 'tls' and
1087 'x509' settings to enable use of SSL and server certificates. This
1088 ensures a data encryption preventing compromise of authentication
1089 credentials.
1091 @item disable-ticketing
1092 Allow client connects without authentication.
1094 @item disable-copy-paste
1095 Disable copy paste between the client and the guest.
1097 @item disable-agent-file-xfer
1098 Disable spice-vdagent based file-xfer between the client and the guest.
1100 @item tls-port=<nr>
1101 Set the TCP port spice is listening on for encrypted channels.
1103 @item x509-dir=<dir>
1104 Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1106 @item x509-key-file=<file>
1107 @itemx x509-key-password=<file>
1108 @itemx x509-cert-file=<file>
1109 @itemx x509-cacert-file=<file>
1110 @itemx x509-dh-key-file=<file>
1111 The x509 file names can also be configured individually.
1113 @item tls-ciphers=<list>
1114 Specify which ciphers to use.
1116 @item tls-channel=[main|display|cursor|inputs|record|playback]
1117 @itemx plaintext-channel=[main|display|cursor|inputs|record|playback]
1118 Force specific channel to be used with or without TLS encryption. The
1119 options can be specified multiple times to configure multiple
1121 mode. For channels which are not explicitly forced into one mode the
1122 spice client is allowed to pick tls/plaintext as he pleases.
1124 @item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1125 Configure image compression (lossless).
1126 Default is auto_glz.
1128 @item jpeg-wan-compression=[auto|never|always]
1129 @itemx zlib-glz-wan-compression=[auto|never|always]
1130 Configure wan image compression (lossy for slow links).
1131 Default is auto.
1133 @item streaming-video=[off|all|filter]
1134 Configure video stream detection. Default is filter.
1136 @item agent-mouse=[on|off]
1137 Enable/disable passing mouse events via vdagent. Default is on.
1139 @item playback-compression=[on|off]
1140 Enable/disable audio stream compression (using celt 0.5.1). Default is on.
1142 @item seamless-migration=[on|off]
1143 Enable/disable spice seamless migration. Default is off.
1145 @end table
1146 ETEXI
1150 QEMU_ARCH_ALL)
1151 STEXI
1152 @item -portrait
1153 @findex -portrait
1154 Rotate graphical output 90 deg left (only PXA LCD).
1155 ETEXI
1159 QEMU_ARCH_ALL)
1160 STEXI
1161 @item -rotate @var{deg}
1162 @findex -rotate
1163 Rotate graphical output some deg left (only PXA LCD).
1164 ETEXI
1169 STEXI
1170 @item -vga @var{type}
1171 @findex -vga
1172 Select type of VGA card to emulate. Valid values for @var{type} are
1173 @table @option
1174 @item cirrus
1175 Cirrus Logic GD5446 Video card. All Windows versions starting from
1176 Windows 95 should recognize and use this graphic card. For optimal
1177 performances, use 16 bit color depth in the guest and the host OS.
1178 (This one is the default)
1179 @item std
1180 Standard VGA card with Bochs VBE extensions. If your guest OS
1181 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1182 to use high resolution modes (>= 1280x1024x16) then you should use
1183 this option.
1184 @item vmware
1185 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1186 recent XFree86/XOrg server or Windows guest with a driver for this
1187 card.
1188 @item qxl
1189 QXL paravirtual graphic card. It is VGA compatible (including VESA
1190 2.0 VBE support). Works best with qxl guest drivers installed though.
1191 Recommended choice when using the spice protocol.
1192 @item tcx
1193 (sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1194 sun4m machines and offers both 8-bit and 24-bit colour depths at a
1195 fixed resolution of 1024x768.
1196 @item cg3
1197 (sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1198 for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1199 resolutions aimed at people wishing to run older Solaris versions.
1200 @item virtio
1201 Virtio VGA card.
1202 @item none
1203 Disable VGA card.
1204 @end table
1205 ETEXI
1209 STEXI
1210 @item -full-screen
1211 @findex -full-screen
1212 Start in full screen.
1213 ETEXI
1217 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1218 STEXI
1219 @item -g @var{width}x@var{height}[x@var{depth}]
1220 @findex -g
1221 Set the initial graphical resolution and depth (PPC, SPARC only).
1222 ETEXI
1226 STEXI
1227 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1228 @findex -vnc
1229 Normally, QEMU uses SDL to display the VGA output. With this option,
1230 you can have QEMU listen on VNC display @var{display} and redirect the VGA
1231 display over the VNC session. It is very useful to enable the usb
1232 tablet device when using this option (option @option{-usbdevice
1233 tablet}). When using the VNC display, you must use the @option{-k}
1234 parameter to set the keyboard layout if you are not using en-us. Valid
1235 syntax for the @var{display} is
1237 @table @option
1239 @item @var{host}:@var{d}
1241 TCP connections will only be allowed from @var{host} on display @var{d}.
1242 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1243 be omitted in which case the server will accept connections from any host.
1245 @item unix:@var{path}
1247 Connections will be allowed over UNIX domain sockets where @var{path} is the
1248 location of a unix socket to listen for connections on.
1250 @item none
1252 VNC is initialized but not started. The monitor @code{change} command
1253 can be used to later start the VNC server.
1255 @end table
1257 Following the @var{display} value there may be one or more @var{option} flags
1258 separated by commas. Valid options are
1260 @table @option
1262 @item reverse
1264 Connect to a listening VNC client via a ``reverse'' connection. The
1265 client is specified by the @var{display}. For reverse network
1266 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1267 is a TCP port number, not a display number.
1269 @item websocket
1271 Opens an additional TCP listening port dedicated to VNC Websocket connections.
1272 By definition the Websocket port is 5700+@var{display}. If @var{host} is
1273 specified connections will only be allowed from this host.
1274 As an alternative the Websocket port could be specified by using
1275 @code{websocket}=@var{port}.
1276 If no TLS credentials are provided, the websocket connection runs in
1277 unencrypted mode. If TLS credentials are provided, the websocket connection
1278 requires encrypted client connections.
1280 @item password
1282 Require that password based authentication is used for client connections.
1284 The password must be set separately using the @code{set_password} command in
1285 the @ref{pcsys_monitor}. The syntax to change your password is:
1286 @code{set_password <protocol> <password>} where <protocol> could be either
1289 If you would like to change <protocol> password expiration, you should use
1290 @code{expire_password <protocol> <expiration-time>} where expiration time could
1291 be one of the following options: now, never, +seconds or UNIX time of
1292 expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1294 date and time).
1297 allow <protocol> password to expire immediately or never expire.
1299 @item tls-creds=@var{ID}
1301 Provides the ID of a set of TLS credentials to use to secure the
1302 VNC server. They will apply to both the normal VNC server socket
1303 and the websocket socket (if enabled). Setting TLS credentials
1304 will cause the VNC server socket to enable the VeNCrypt auth
1305 mechanism. The credentials should have been previously created
1306 using the @option{-object tls-creds} argument.
1308 The @option{tls-creds} parameter obsoletes the @option{tls},
1309 @option{x509}, and @option{x509verify} options, and as such
1310 it is not permitted to set both new and old type options at
1311 the same time.
1313 @item tls
1315 Require that client use TLS when communicating with the VNC server. This
1316 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1317 attack. It is recommended that this option be combined with either the
1318 @option{x509} or @option{x509verify} options.
1320 This option is now deprecated in favor of using the @option{tls-creds}
1321 argument.
1323 @item x509=@var{/path/to/certificate/dir}
1325 Valid if @option{tls} is specified. Require that x509 credentials are used
1326 for negotiating the TLS session. The server will send its x509 certificate
1327 to the client. It is recommended that a password be set on the VNC server
1328 to provide authentication of the client when this is used. The path following
1329 this option specifies where the x509 certificates are to be loaded from.
1330 See the @ref{vnc_security} section for details on generating certificates.
1332 This option is now deprecated in favour of using the @option{tls-creds}
1333 argument.
1335 @item x509verify=@var{/path/to/certificate/dir}
1337 Valid if @option{tls} is specified. Require that x509 credentials are used
1338 for negotiating the TLS session. The server will send its x509 certificate
1339 to the client, and request that the client send its own x509 certificate.
1340 The server will validate the client's certificate against the CA certificate,
1341 and reject clients when validation fails. If the certificate authority is
1342 trusted, this is a sufficient authentication mechanism. You may still wish
1343 to set a password on the VNC server as a second authentication layer. The
1344 path following this option specifies where the x509 certificates are to
1345 be loaded from. See the @ref{vnc_security} section for details on generating
1346 certificates.
1348 This option is now deprecated in favour of using the @option{tls-creds}
1349 argument.
1351 @item sasl
1353 Require that the client use SASL to authenticate with the VNC server.
1354 The exact choice of authentication method used is controlled from the
1355 system / user's SASL configuration file for the 'qemu' service. This
1356 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1357 unprivileged user, an environment variable SASL_CONF_PATH can be used
1358 to make it search alternate locations for the service config.
1359 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1360 it is recommended that SASL always be combined with the 'tls' and
1361 'x509' settings to enable use of SSL and server certificates. This
1362 ensures a data encryption preventing compromise of authentication
1363 credentials. See the @ref{vnc_security} section for details on using
1364 SASL authentication.
1366 @item acl
1368 Turn on access control lists for checking of the x509 client certificate
1369 and SASL party. For x509 certs, the ACL check is made against the
1370 certificate's distinguished name. This is something that looks like
1371 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1372 made against the username, which depending on the SASL plugin, may
1373 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1374 When the @option{acl} flag is set, the initial access list will be
1375 empty, with a @code{deny} policy. Thus no one will be allowed to
1376 use the VNC server until the ACLs have been loaded. This can be
1377 achieved using the @code{acl} monitor command.
1379 @item lossy
1381 Enable lossy compression methods (gradient, JPEG, ...). If this
1382 option is set, VNC client may receive lossy framebuffer updates
1383 depending on its encoding settings. Enabling this option can save
1384 a lot of bandwidth at the expense of quality.
1386 @item non-adaptive
1388 Disable adaptive encodings. Adaptive encodings are enabled by default.
1389 An adaptive encoding will try to detect frequently updated screen regions,
1390 and send updates in these regions using a lossy encoding (like JPEG).
1391 This can be really helpful to save bandwidth when playing videos. Disabling
1392 adaptive encodings restores the original static behavior of encodings
1393 like Tight.
1395 @item share=[allow-exclusive|force-shared|ignore]
1397 Set display sharing policy. 'allow-exclusive' allows clients to ask
1398 for exclusive access. As suggested by the rfb spec this is
1399 implemented by dropping other connections. Connecting multiple
1400 clients in parallel requires all clients asking for a shared session
1401 (vncviewer: -shared switch). This is the default. 'force-shared'
1402 disables exclusive client access. Useful for shared desktop sessions,
1403 where you don't want someone forgetting specify -shared disconnect
1404 everybody else. 'ignore' completely ignores the shared flag and
1405 allows everybody connect unconditionally. Doesn't conform to the rfb
1406 spec but is traditional QEMU behavior.
1408 @end table
1409 ETEXI
1411 STEXI
1412 @end table
1413 ETEXI
1414 ARCHHEADING(, QEMU_ARCH_I386)
1416 ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1417 STEXI
1418 @table @option
1419 ETEXI
1423 QEMU_ARCH_I386)
1424 STEXI
1425 @item -win2k-hack
1426 @findex -win2k-hack
1427 Use it when installing Windows 2000 to avoid a disk full bug. After
1428 Windows 2000 is installed, you no longer need this option (this option
1429 slows down the IDE transfers).
1430 ETEXI
1432 HXCOMM Deprecated by -rtc
1437 QEMU_ARCH_I386)
1438 STEXI
1439 @item -no-fd-bootchk
1440 @findex -no-fd-bootchk
1441 Disable boot signature checking for floppy disks in BIOS. May
1442 be needed to boot from old floppy disks.
1443 ETEXI
1447 STEXI
1448 @item -no-acpi
1449 @findex -no-acpi
1450 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1451 it if your guest OS complains about ACPI problems (PC target machine
1452 only).
1453 ETEXI
1457 STEXI
1458 @item -no-hpet
1459 @findex -no-hpet
1460 Disable HPET support.
1461 ETEXI
1464 "-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"
1466 STEXI
1467 @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}]...]
1468 @findex -acpitable
1469 Add ACPI table with specified header fields and context from specified files.
1470 For file=, take whole ACPI table from the specified files, including all
1471 ACPI headers (possible overridden by other options).
1472 For data=, only data
1473 portion of the table is used, all header information is specified in the
1474 command line.
1475 If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id
1476 fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order
1477 to ensure the field matches required by the Microsoft SLIC spec and the ACPI
1478 spec.
1479 ETEXI
1502 QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1503 STEXI
1504 @item -smbios file=@var{binary}
1505 @findex -smbios
1506 Load SMBIOS entry from binary file.
1508 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1509 Specify SMBIOS type 0 fields
1511 @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}]
1512 Specify SMBIOS type 1 fields
1514 @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}]
1515 Specify SMBIOS type 2 fields
1517 @item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}]
1518 Specify SMBIOS type 3 fields
1520 @item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}]
1521 Specify SMBIOS type 4 fields
1523 @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}]
1524 Specify SMBIOS type 17 fields
1525 ETEXI
1527 STEXI
1528 @end table
1529 ETEXI
1530 DEFHEADING()
1532 DEFHEADING(Network options:)
1533 STEXI
1534 @table @option
1535 ETEXI
1537 HXCOMM Legacy slirp options (now moved to -net user):
1538 #ifdef CONFIG_SLIRP
1542 #ifndef _WIN32
1544 #endif
1545 #endif
1548 #ifdef CONFIG_SLIRP
1552 #ifndef _WIN32
1554 #endif
1557 #endif
1558 #ifdef _WIN32
1561 #else
1588 #endif
1589 #ifdef __linux__
1615 #endif
1625 #ifdef CONFIG_VDE
1631 #endif
1632 #ifdef CONFIG_NETMAP
1637 #endif
1651 #ifdef CONFIG_SLIRP
1653 #endif
1656 #ifdef CONFIG_VDE
1658 #endif
1659 #ifdef CONFIG_NETMAP
1661 #endif
1665 STEXI
1666 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1667 @findex -net
1668 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1669 = 0 is the default). The NIC is an e1000 by default on the PC
1670 target. Optionally, the MAC address can be changed to @var{mac}, the
1671 device address set to @var{addr} (PCI cards only),
1672 and a @var{name} can be assigned for use in monitor commands.
1673 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1674 that the card should have; this option currently only affects virtio cards; set
1675 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1676 NIC is created. QEMU can emulate several different models of network card.
1677 Valid values for @var{type} are
1678 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1679 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1680 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1681 Not all devices are supported on all targets. Use @code{-net nic,model=help}
1682 for a list of available devices for your target.
1684 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
1685 @findex -netdev
1686 @item -net user[,@var{option}][,@var{option}][,...]
1687 Use the user mode network stack which requires no administrator
1688 privilege to run. Valid options are:
1690 @table @option
1691 @item vlan=@var{n}
1692 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1694 @item id=@var{id}
1695 @itemx name=@var{name}
1696 Assign symbolic name for use in monitor commands.
1698 @item net=@var{addr}[/@var{mask}]
1699 Set IP network address the guest will see. Optionally specify the netmask,
1700 either in the form a.b.c.d or as number of valid top-most bits. Default is
1701 10.0.2.0/24.
1703 @item host=@var{addr}
1704 Specify the guest-visible address of the host. Default is the 2nd IP in the
1705 guest network, i.e. x.x.x.2.
1707 @item restrict=on|off
1708 If this option is enabled, the guest will be isolated, i.e. it will not be
1709 able to contact the host and no guest IP packets will be routed over the host
1710 to the outside. This option does not affect any explicitly set forwarding rules.
1712 @item hostname=@var{name}
1713 Specifies the client hostname reported by the built-in DHCP server.
1715 @item dhcpstart=@var{addr}
1716 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1717 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1719 @item dns=@var{addr}
1720 Specify the guest-visible address of the virtual nameserver. The address must
1721 be different from the host address. Default is the 3rd IP in the guest network,
1722 i.e. x.x.x.3.
1724 @item dnssearch=@var{domain}
1725 Provides an entry for the domain-search list sent by the built-in
1726 DHCP server. More than one domain suffix can be transmitted by specifying
1727 this option multiple times. If supported, this will cause the guest to
1728 automatically try to append the given domain suffix(es) in case a domain name
1729 can not be resolved.
1731 Example:
1732 @example
1733 qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
1734 @end example
1736 @item tftp=@var{dir}
1737 When using the user mode network stack, activate a built-in TFTP
1738 server. The files in @var{dir} will be exposed as the root of a TFTP server.
1739 The TFTP client on the guest must be configured in binary mode (use the command
1740 @code{bin} of the Unix TFTP client).
1742 @item bootfile=@var{file}
1743 When using the user mode network stack, broadcast @var{file} as the BOOTP
1744 filename. In conjunction with @option{tftp}, this can be used to network boot
1745 a guest from a local directory.
1747 Example (using pxelinux):
1748 @example
1749 qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1750 @end example
1752 @item smb=@var{dir}[,smbserver=@var{addr}]
1753 When using the user mode network stack, activate a built-in SMB
1754 server so that Windows OSes can access to the host files in @file{@var{dir}}
1755 transparently. The IP address of the SMB server can be set to @var{addr}. By
1756 default the 4th IP in the guest network is used, i.e. x.x.x.4.
1758 In the guest Windows OS, the line:
1759 @example
1760 10.0.2.4 smbserver
1761 @end example
1762 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1763 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1767 Note that a SAMBA server must be installed on the host OS.
1768 QEMU was tested successfully with smbd versions from Red Hat 9,
1769 Fedora Core 3 and OpenSUSE 11.x.
1771 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1772 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1773 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1774 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1775 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1776 be bound to a specific host interface. If no connection type is set, TCP is
1777 used. This option can be given multiple times.
1779 For example, to redirect host X11 connection from screen 1 to guest
1780 screen 0, use the following:
1782 @example
1783 # on the host
1784 qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1785 # this host xterm should open in the guest X11 server
1786 xterm -display :1
1787 @end example
1789 To redirect telnet connections from host port 5555 to telnet port on
1790 the guest, use the following:
1792 @example
1793 # on the host
1794 qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
1795 telnet localhost 5555
1796 @end example
1798 Then when you use on the host @code{telnet localhost 5555}, you
1799 connect to the guest telnet server.
1801 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1802 @itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
1803 Forward guest TCP connections to the IP address @var{server} on port @var{port}
1804 to the character device @var{dev} or to a program executed by @var{cmd:command}
1805 which gets spawned for each connection. This option can be given multiple times.
1807 You can either use a chardev directly and have that one used throughout QEMU's
1808 lifetime, like in the following example:
1810 @example
1811 # open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
1812 # the guest accesses it
1813 qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...]
1814 @end example
1816 Or you can execute a command on every TCP connection established by the guest,
1817 so that QEMU behaves similar to an inetd process for that virtual server:
1819 @example
1821 # and connect the TCP stream to its stdin/stdout
1822 qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
1823 @end example
1825 @end table
1827 Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
1828 processed and applied to -net user. Mixing them with the new configuration
1829 syntax gives undefined results. Their use for new applications is discouraged
1830 as they will be removed from future versions.
1832 @item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1833 @itemx -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,helper=@var{helper}]
1834 Connect the host TAP network interface @var{name} to VLAN @var{n}.
1836 Use the network script @var{file} to configure it and the network script
1837 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
1838 automatically provides one. The default network configure script is
1839 @file{/etc/qemu-ifup} and the default network deconfigure script is
1840 @file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
1841 to disable script execution.
1843 If running QEMU as an unprivileged user, use the network helper
1844 @var{helper} to configure the TAP interface. The default network
1845 helper executable is @file{/path/to/qemu-bridge-helper}.
1847 @option{fd}=@var{h} can be used to specify the handle of an already
1848 opened host TAP interface.
1850 Examples:
1852 @example
1853 #launch a QEMU instance with the default network script
1854 qemu-system-i386 linux.img -net nic -net tap
1855 @end example
1857 @example
1858 #launch a QEMU instance with two NICs, each one connected
1859 #to a TAP device
1860 qemu-system-i386 linux.img \
1861 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
1862 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
1863 @end example
1865 @example
1866 #launch a QEMU instance with the default network helper to
1867 #connect a TAP device to bridge br0
1868 qemu-system-i386 linux.img \
1870 @end example
1872 @item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
1873 @itemx -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
1874 Connect a host TAP network interface to a host bridge device.
1876 Use the network helper @var{helper} to configure the TAP interface and
1877 attach it to the bridge. The default network helper executable is
1878 @file{/path/to/qemu-bridge-helper} and the default bridge
1879 device is @file{br0}.
1881 Examples:
1883 @example
1884 #launch a QEMU instance with the default network helper to
1885 #connect a TAP device to bridge br0
1886 qemu-system-i386 linux.img -net bridge -net nic,model=virtio
1887 @end example
1889 @example
1890 #launch a QEMU instance with the default network helper to
1891 #connect a TAP device to bridge qemubr0
1892 qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
1893 @end example
1895 @item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1896 @itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1898 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
1899 machine using a TCP socket connection. If @option{listen} is
1900 specified, QEMU waits for incoming connections on @var{port}
1901 (@var{host} is optional). @option{connect} is used to connect to
1902 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
1903 specifies an already opened TCP socket.
1905 Example:
1906 @example
1907 # launch a first QEMU instance
1908 qemu-system-i386 linux.img \
1909 -net nic,macaddr=52:54:00:12:34:56 \
1910 -net socket,listen=:1234
1911 # connect the VLAN 0 of this instance to the VLAN 0
1912 # of the first instance
1913 qemu-system-i386 linux.img \
1914 -net nic,macaddr=52:54:00:12:34:57 \
1915 -net socket,connect=127.0.0.1:1234
1916 @end example
1918 @item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1919 @itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1921 Create a VLAN @var{n} shared with another QEMU virtual
1922 machines using a UDP multicast socket, effectively making a bus for
1923 every QEMU with same multicast address @var{maddr} and @var{port}.
1924 NOTES:
1925 @enumerate
1926 @item
1927 Several QEMU can be running on different hosts and share same bus (assuming
1928 correct multicast setup for these hosts).
1929 @item
1930 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
1931 @url{http://user-mode-linux.sf.net}.
1932 @item
1933 Use @option{fd=h} to specify an already opened UDP multicast socket.
1934 @end enumerate
1936 Example:
1937 @example
1938 # launch one QEMU instance
1939 qemu-system-i386 linux.img \
1940 -net nic,macaddr=52:54:00:12:34:56 \
1941 -net socket,mcast=230.0.0.1:1234
1943 qemu-system-i386 linux.img \
1944 -net nic,macaddr=52:54:00:12:34:57 \
1945 -net socket,mcast=230.0.0.1:1234
1947 qemu-system-i386 linux.img \
1948 -net nic,macaddr=52:54:00:12:34:58 \
1949 -net socket,mcast=230.0.0.1:1234
1950 @end example
1952 Example (User Mode Linux compat.):
1953 @example
1954 # launch QEMU instance (note mcast address selected
1955 # is UML's default)
1956 qemu-system-i386 linux.img \
1957 -net nic,macaddr=52:54:00:12:34:56 \
1958 -net socket,mcast=239.192.168.1:1102
1959 # launch UML
1960 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
1961 @end example
1963 Example (send packets from host's 1.2.3.4):
1964 @example
1965 qemu-system-i386 linux.img \
1966 -net nic,macaddr=52:54:00:12:34:56 \
1967 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
1968 @end example
1970 @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}]
1971 @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}]
1972 Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular
1973 protocol to transport Ethernet (and other Layer 2) data frames between
1974 two systems. It is present in routers, firewalls and the Linux kernel
1975 (from version 3.3 onwards).
1977 This transport allows a VM to communicate to another VM, router or firewall directly.
1979 @item src=@var{srcaddr}
1980 source address (mandatory)
1981 @item dst=@var{dstaddr}
1982 destination address (mandatory)
1983 @item udp
1984 select udp encapsulation (default is ip).
1985 @item srcport=@var{srcport}
1986 source udp port.
1987 @item dstport=@var{dstport}
1988 destination udp port.
1989 @item ipv6
1990 force v6, otherwise defaults to v4.
1991 @item rxcookie=@var{rxcookie}
1992 @itemx txcookie=@var{txcookie}
1993 Cookies are a weak form of security in the l2tpv3 specification.
1994 Their function is mostly to prevent misconfiguration. By default they are 32
1995 bit.
1996 @item cookie64
1997 Set cookie size to 64 bit instead of the default 32
1998 @item counter=off
1999 Force a 'cut-down' L2TPv3 with no counter as in
2000 draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00
2001 @item pincounter=on
2002 Work around broken counter handling in peer. This may also help on
2003 networks which have packet reorder.
2004 @item offset=@var{offset}
2005 Add an extra offset between header and data
2007 For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan
2008 on the remote Linux host 1.2.3.4:
2009 @example
2010 # Setup tunnel on linux host using raw ip as encapsulation
2011 # on 1.2.3.4
2012 ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \
2013 encap udp udp_sport 16384 udp_dport 16384
2014 ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \
2015 0xFFFFFFFF peer_session_id 0xFFFFFFFF
2016 ifconfig vmtunnel0 mtu 1500
2017 ifconfig vmtunnel0 up
2018 brctl addif br-lan vmtunnel0
2021 # on 4.3.2.1
2022 # launch QEMU instance - if your network has reorder or is very lossy add ,pincounter
2024 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
2027 @end example
2029 @item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2030 @itemx -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2031 Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
2032 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
2033 and MODE @var{octalmode} to change default ownership and permissions for
2034 communication port. This option is only available if QEMU has been compiled
2035 with vde support enabled.
2037 Example:
2038 @example
2039 # launch vde switch
2040 vde_switch -F -sock /tmp/myswitch
2041 # launch QEMU instance
2042 qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch
2043 @end example
2045 @item -netdev hubport,id=@var{id},hubid=@var{hubid}
2050 netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the
2051 required hub automatically.
2053 @item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n]
2055 Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should
2056 be a unix domain socket backed one. The vhost-user uses a specifically defined
2057 protocol to pass vhost ioctl replacement messages to an application on the other
2058 end of the socket. On non-MSIX guests, the feature can be forced with
2059 @var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to
2060 be created for multiqueue vhost-user.
2062 Example:
2063 @example
2064 qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \
2065 -numa node,memdev=mem \
2066 -chardev socket,path=/path/to/socket \
2067 -netdev type=vhost-user,id=net0,chardev=chr0 \
2068 -device virtio-net-pci,netdev=net0
2069 @end example
2071 @item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
2072 Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
2073 At most @var{len} bytes (64k by default) per packet are stored. The file format is
2074 libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
2075 Note: For devices created with '-netdev', use '-object filter-dump,...' instead.
2077 @item -net none
2078 Indicate that no network devices should be configured. It is used to
2079 override the default configuration (@option{-net nic -net user}) which
2080 is activated if no @option{-net} options are provided.
2081 ETEXI
2083 STEXI
2084 @end table
2085 ETEXI
2086 DEFHEADING()
2088 DEFHEADING(Character device options:)
2089 STEXI
2091 The general form of a character device option is:
2092 @table @option
2093 ETEXI
2097 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
2111 #ifdef _WIN32
2114 #else
2117 #endif
2118 #ifdef CONFIG_BRLAPI
2120 #endif
2121 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
2122 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
2125 #endif
2126 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
2129 #endif
2130 #if defined(CONFIG_SPICE)
2133 #endif
2134 , QEMU_ARCH_ALL
2135 )
2137 STEXI
2138 @item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
2139 @findex -chardev
2140 Backend is one of:
2141 @option{null},
2142 @option{socket},
2143 @option{udp},
2144 @option{msmouse},
2145 @option{vc},
2146 @option{ringbuf},
2147 @option{file},
2148 @option{pipe},
2149 @option{console},
2150 @option{serial},
2151 @option{pty},
2152 @option{stdio},
2153 @option{braille},
2154 @option{tty},
2155 @option{parallel},
2156 @option{parport},
2157 @option{spicevmc}.
2158 @option{spiceport}.
2159 The specific backend will determine the applicable options.
2161 All devices must have an id, which can be any string up to 127 characters long.
2162 It is used to uniquely identify this device in other command line directives.
2164 A character device may be used in multiplexing mode by multiple front-ends.
2165 The key sequence of @key{Control-a} and @key{c} will rotate the input focus
2166 between attached front-ends. Specify @option{mux=on} to enable this mode.
2168 Every backend supports the @option{logfile} option, which supplies the path
2169 to a file to record all data transmitted via the backend. The @option{logappend}
2170 option controls whether the log file will be truncated or appended to when
2171 opened.
2173 Further options to each backend are described below.
2175 @item -chardev null ,id=@var{id}
2176 A void device. This device will not emit any data, and will drop any data it
2177 receives. The null backend does not take any options.
2179 @item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}] [,tls-creds=@var{id}]
2181 Create a two-way stream socket, which can be either a TCP or a unix socket. A
2182 unix socket will be created if @option{path} is specified. Behaviour is
2183 undefined if TCP options are specified for a unix socket.
2185 @option{server} specifies that the socket shall be a listening socket.
2187 @option{nowait} specifies that QEMU should not block waiting for a client to
2188 connect to a listening socket.
2190 @option{telnet} specifies that traffic on the socket should interpret telnet
2191 escape sequences.
2193 @option{reconnect} sets the timeout for reconnecting on non-server sockets when
2194 the remote end goes away. qemu will delay this many seconds and then attempt
2195 to reconnect. Zero disables reconnecting, and is the default.
2197 @option{tls-creds} requests enablement of the TLS protocol for encryption,
2198 and specifies the id of the TLS credentials to use for the handshake. The
2199 credentials must be previously created with the @option{-object tls-creds}
2200 argument.
2202 TCP and unix socket options are given below:
2204 @table @option
2206 @item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
2208 @option{host} for a listening socket specifies the local address to be bound.
2209 For a connecting socket species the remote host to connect to. @option{host} is
2210 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
2212 @option{port} for a listening socket specifies the local port to be bound. For a
2213 connecting socket specifies the port on the remote host to connect to.
2214 @option{port} can be given as either a port number or a service name.
2215 @option{port} is required.
2217 @option{to} is only relevant to listening sockets. If it is specified, and
2218 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
2219 to and including @option{to} until it succeeds. @option{to} must be specified
2220 as a port number.
2222 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2223 If neither is specified the socket may use either protocol.
2225 @option{nodelay} disables the Nagle algorithm.
2227 @item unix options: path=@var{path}
2229 @option{path} specifies the local path of the unix socket. @option{path} is
2230 required.
2232 @end table
2234 @item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
2236 Sends all traffic from the guest to a remote host over UDP.
2238 @option{host} specifies the remote host to connect to. If not specified it
2239 defaults to @code{localhost}.
2241 @option{port} specifies the port on the remote host to connect to. @option{port}
2242 is required.
2244 @option{localaddr} specifies the local address to bind to. If not specified it
2245 defaults to @code{0.0.0.0}.
2247 @option{localport} specifies the local port to bind to. If not specified any
2248 available local port will be used.
2250 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2251 If neither is specified the device may use either protocol.
2253 @item -chardev msmouse ,id=@var{id}
2255 Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
2256 take any options.
2258 @item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
2260 Connect to a QEMU text console. @option{vc} may optionally be given a specific
2261 size.
2263 @option{width} and @option{height} specify the width and height respectively of
2264 the console, in pixels.
2266 @option{cols} and @option{rows} specify that the console be sized to fit a text
2267 console with the given dimensions.
2269 @item -chardev ringbuf ,id=@var{id} [,size=@var{size}]
2271 Create a ring buffer with fixed size @option{size}.
2272 @var{size} must be a power of two, and defaults to @code{64K}).
2274 @item -chardev file ,id=@var{id} ,path=@var{path}
2276 Log all traffic received from the guest to a file.
2278 @option{path} specifies the path of the file to be opened. This file will be
2279 created if it does not already exist, and overwritten if it does. @option{path}
2280 is required.
2282 @item -chardev pipe ,id=@var{id} ,path=@var{path}
2284 Create a two-way connection to the guest. The behaviour differs slightly between
2285 Windows hosts and other hosts:
2287 On Windows, a single duplex pipe will be created at
2290 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
2291 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
2292 received by the guest. Data written by the guest can be read from
2293 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
2294 be present.
2296 @option{path} forms part of the pipe path as described above. @option{path} is
2297 required.
2299 @item -chardev console ,id=@var{id}
2301 Send traffic from the guest to QEMU's standard output. @option{console} does not
2302 take any options.
2304 @option{console} is only available on Windows hosts.
2306 @item -chardev serial ,id=@var{id} ,path=@option{path}
2308 Send traffic from the guest to a serial device on the host.
2310 On Unix hosts serial will actually accept any tty device,
2311 not only serial lines.
2313 @option{path} specifies the name of the serial device to open.
2315 @item -chardev pty ,id=@var{id}
2317 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2318 not take any options.
2320 @option{pty} is not available on Windows hosts.
2322 @item -chardev stdio ,id=@var{id} [,signal=on|off]
2323 Connect to standard input and standard output of the QEMU process.
2325 @option{signal} controls if signals are enabled on the terminal, that includes
2326 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2327 default, use @option{signal=off} to disable it.
2329 @option{stdio} is not available on Windows hosts.
2331 @item -chardev braille ,id=@var{id}
2333 Connect to a local BrlAPI server. @option{braille} does not take any options.
2335 @item -chardev tty ,id=@var{id} ,path=@var{path}
2337 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2338 DragonFlyBSD hosts. It is an alias for @option{serial}.
2340 @option{path} specifies the path to the tty. @option{path} is required.
2342 @item -chardev parallel ,id=@var{id} ,path=@var{path}
2343 @itemx -chardev parport ,id=@var{id} ,path=@var{path}
2345 @option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2347 Connect to a local parallel port.
2349 @option{path} specifies the path to the parallel port device. @option{path} is
2350 required.
2352 @item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2354 @option{spicevmc} is only available when spice support is built in.
2356 @option{debug} debug level for spicevmc
2358 @option{name} name of spice channel to connect to
2360 Connect to a spice virtual machine channel, such as vdiport.
2362 @item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2364 @option{spiceport} is only available when spice support is built in.
2366 @option{debug} debug level for spicevmc
2368 @option{name} name of spice port to connect to
2370 Connect to a spice port, allowing a Spice client to handle the traffic
2371 identified by a name (preferably a fqdn).
2372 ETEXI
2374 STEXI
2375 @end table
2376 ETEXI
2377 DEFHEADING()
2379 DEFHEADING(Device URL Syntax:)
2380 STEXI
2382 In addition to using normal file images for the emulated storage devices,
2383 QEMU can also use networked resources such as iSCSI devices. These are
2384 specified using a special URL syntax.
2386 @table @option
2387 @item iSCSI
2388 iSCSI support allows QEMU to access iSCSI resources directly and use as
2389 images for the guest storage. Both disk and cdrom images are supported.
2391 Syntax for specifying iSCSI LUNs is
2392 ``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
2394 By default qemu will use the iSCSI initiator-name
2395 'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command
2396 line or a configuration file.
2398 Since version Qemu 2.4 it is possible to specify a iSCSI request timeout to detect
2399 stalled requests and force a reestablishment of the session. The timeout
2400 is specified in seconds. The default is 0 which means no timeout. Libiscsi
2401 1.15.0 or greater is required for this feature.
2403 Example (without authentication):
2404 @example
2405 qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
2406 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
2407 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2408 @end example
2410 Example (CHAP username/password via URL):
2411 @example
2412 qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
2413 @end example
2415 Example (CHAP username/password via environment variables):
2416 @example
2419 qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2420 @end example
2422 iSCSI support is an optional feature of QEMU and only available when
2423 compiled and linked against libiscsi.
2424 ETEXI
2431 STEXI
2433 iSCSI parameters such as username and password can also be specified via
2434 a configuration file. See qemu-doc for more information and examples.
2436 @item NBD
2437 QEMU supports NBD (Network Block Devices) both using TCP protocol as well
2438 as Unix Domain Sockets.
2440 Syntax for specifying a NBD device using TCP
2441 ``nbd:<server-ip>:<port>[:exportname=<export>]''
2443 Syntax for specifying a NBD device using Unix Domain Sockets
2444 ``nbd:unix:<domain-socket>[:exportname=<export>]''
2447 Example for TCP
2448 @example
2449 qemu-system-i386 --drive file=nbd:192.0.2.1:30000
2450 @end example
2452 Example for Unix Domain Sockets
2453 @example
2454 qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket
2455 @end example
2457 @item SSH
2458 QEMU supports SSH (Secure Shell) access to remote disks.
2460 Examples:
2461 @example
2462 qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img
2463 qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img
2464 @end example
2466 Currently authentication must be done using ssh-agent. Other
2467 authentication methods may be supported in future.
2469 @item Sheepdog
2470 Sheepdog is a distributed storage system for QEMU.
2471 QEMU supports using either local sheepdog devices or remote networked
2472 devices.
2474 Syntax for specifying a sheepdog device
2475 @example
2476 sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag]
2477 @end example
2479 Example
2480 @example
2481 qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine
2482 @end example
2484 See also @url{http://http://www.osrg.net/sheepdog/}.
2486 @item GlusterFS
2487 GlusterFS is an user space distributed file system.
2488 QEMU supports the use of GlusterFS volumes for hosting VM disk images using
2489 TCP, Unix Domain Sockets and RDMA transport protocols.
2491 Syntax for specifying a VM disk image on GlusterFS volume is
2492 @example
2493 gluster[+transport]://[server[:port]]/volname/image[?socket=...]
2494 @end example
2497 Example
2498 @example
2499 qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img
2500 @end example
2502 See also @url{http://www.gluster.org}.
2504 @item HTTP/HTTPS/FTP/FTPS/TFTP
2505 QEMU supports read-only access to files accessed over http(s), ftp(s) and tftp.
2507 Syntax using a single filename:
2508 @example
2509 <protocol>://[<username>[:<password>]@@]<host>/<path>
2510 @end example
2512 where:
2513 @table @option
2514 @item protocol
2515 'http', 'https', 'ftp', 'ftps', or 'tftp'.
2517 @item username
2518 Optional username for authentication to the remote server.
2520 @item password
2521 Optional password for authentication to the remote server.
2523 @item host
2524 Address of the remote server.
2526 @item path
2527 Path on the remote server, including any query string.
2528 @end table
2530 The following options are also supported:
2531 @table @option
2532 @item url
2533 The full URL when passing options to the driver explicitly.
2535 @item readahead
2536 The amount of data to read ahead with each range request to the remote server.
2537 This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it
2538 does not have a suffix, it will be assumed to be in bytes. The value must be a
2539 multiple of 512 bytes. It defaults to 256k.
2541 @item sslverify
2542 Whether to verify the remote server's certificate when connecting over SSL. It
2543 can have the value 'on' or 'off'. It defaults to 'on'.
2545 @item cookie
2546 Send this cookie (it can also be a list of cookies separated by ';') with
2547 each outgoing request. Only supported when using protocols such as HTTP
2548 which support cookies, otherwise ignored.
2550 @item timeout
2551 Set the timeout in seconds of the CURL connection. This timeout is the time
2552 that CURL waits for a response from the remote server to get the size of the
2553 image to be downloaded. If not set, the default timeout of 5 seconds is used.
2554 @end table
2556 Note that when passing options to qemu explicitly, @option{driver} is the value
2557 of <protocol>.
2559 Example: boot from a remote Fedora 20 live ISO image
2560 @example
2561 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
2563 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
2564 @end example
2566 Example: boot from a remote Fedora 20 cloud image using a local overlay for
2567 writes, copy-on-read, and a readahead of 64k
2568 @example
2569 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
2572 @end example
2577 @example
2578 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
2581 @end example
2582 ETEXI
2584 STEXI
2585 @end table
2586 ETEXI
2589 STEXI
2590 @table @option
2591 ETEXI
2603 QEMU_ARCH_ALL)
2604 STEXI
2606 @findex -bt
2609 example when emulating a machine with only one HCI built into it, only
2611 logic. The Transport Layer is decided by the machine type. Currently
2612 the machines @code{n800} and @code{n810} have one HCI and all other
2613 machines have none.
2615 @anchor{bt-hcis}
2616 The following three types are recognized:
2618 @table @option
2619 @item -bt hci,null
2620 (default) The corresponding Bluetooth HCI assumes no internal logic
2621 and will not respond to any HCI commands or emit events.
2623 @item -bt hci,host[:@var{id}]
2624 (@code{bluez} only) The corresponding HCI passes commands / events
2625 to / from the physical HCI identified by the name @var{id} (default:
2626 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
2627 capable systems like Linux.
2629 @item -bt hci[,vlan=@var{n}]
2630 Add a virtual, standard HCI that will participate in the Bluetooth
2631 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
2632 VLANs, devices inside a bluetooth network @var{n} can only communicate
2633 with other devices in the same network (scatternet).
2634 @end table
2636 @item -bt vhci[,vlan=@var{n}]
2637 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2638 to the host bluetooth stack instead of to the emulated target. This
2639 allows the host and target machines to participate in a common scatternet
2640 and communicate. Requires the Linux @code{vhci} driver installed. Can
2641 be used as following:
2643 @example
2644 qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2645 @end example
2647 @item -bt device:@var{dev}[,vlan=@var{n}]
2648 Emulate a bluetooth device @var{dev} and place it in network @var{n}
2649 (default @code{0}). QEMU can only emulate one type of bluetooth devices
2650 currently:
2652 @table @option
2653 @item keyboard
2654 Virtual wireless keyboard implementing the HIDP bluetooth profile.
2655 @end table
2656 ETEXI
2658 STEXI
2659 @end table
2660 ETEXI
2661 DEFHEADING()
2663 #ifdef CONFIG_TPM
2664 DEFHEADING(TPM device options:)
2666 DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
2671 QEMU_ARCH_ALL)
2672 STEXI
2674 The general form of a TPM device option is:
2675 @table @option
2677 @item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
2678 @findex -tpmdev
2679 Backend type must be:
2680 @option{passthrough}.
2682 The specific backend type will determine the applicable options.
2683 The @code{-tpmdev} option creates the TPM backend and requires a
2684 @code{-device} option that specifies the TPM frontend interface model.
2686 Options to each backend are described below.
2688 Use 'help' to print all available TPM backend types.
2689 @example
2690 qemu -tpmdev help
2691 @end example
2693 @item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path}
2695 (Linux-host only) Enable access to the host's TPM using the passthrough
2696 driver.
2698 @option{path} specifies the path to the host's TPM device, i.e., on
2699 a Linux host this would be @code{/dev/tpm0}.
2700 @option{path} is optional and by default @code{/dev/tpm0} is used.
2702 @option{cancel-path} specifies the path to the host TPM device's sysfs
2703 entry allowing for cancellation of an ongoing TPM command.
2704 @option{cancel-path} is optional and by default QEMU will search for the
2705 sysfs entry to use.
2707 Some notes about using the host's TPM with the passthrough driver:
2709 The TPM device accessed by the passthrough driver must not be
2710 used by any other application on the host.
2712 Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
2713 the VM's firmware (BIOS/UEFI) will not be able to initialize the
2714 TPM again and may therefore not show a TPM-specific menu that would
2715 otherwise allow the user to configure the TPM, e.g., allow the user to
2716 enable/disable or activate/deactivate the TPM.
2717 Further, if TPM ownership is released from within a VM then the host's TPM
2718 will get disabled and deactivated. To enable and activate the
2719 TPM again afterwards, the host has to be rebooted and the user is
2720 required to enter the firmware's menu to enable and activate the TPM.
2721 If the TPM is left disabled and/or deactivated most TPM commands will fail.
2723 To create a passthrough TPM use the following two options:
2724 @example
2725 -tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
2726 @end example
2727 Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
2728 @code{tpmdev=tpm0} in the device option.
2730 @end table
2732 ETEXI
2734 DEFHEADING()
2736 #endif
2738 DEFHEADING(Linux/Multiboot boot specific:)
2739 STEXI
2741 When using these options, you can use a given Linux or Multiboot
2742 kernel without installing it in the disk image. It can be useful
2743 for easier testing of various kernels.
2745 @table @option
2746 ETEXI
2750 STEXI
2751 @item -kernel @var{bzImage}
2752 @findex -kernel
2753 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2754 or in multiboot format.
2755 ETEXI
2759 STEXI
2760 @item -append @var{cmdline}
2761 @findex -append
2762 Use @var{cmdline} as kernel command line
2763 ETEXI
2767 STEXI
2768 @item -initrd @var{file}
2769 @findex -initrd
2770 Use @var{file} as initial ram disk.
2774 This syntax is only available with multiboot.
2776 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
2777 first module.
2778 ETEXI
2782 STEXI
2783 @item -dtb @var{file}
2784 @findex -dtb
2785 Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
2786 on boot.
2787 ETEXI
2789 STEXI
2790 @end table
2791 ETEXI
2792 DEFHEADING()
2794 DEFHEADING(Debug/Expert options:)
2795 STEXI
2796 @table @option
2797 ETEXI
2804 QEMU_ARCH_ALL)
2805 STEXI
2806 @item -fw_cfg [name=]@var{name},file=@var{file}
2807 @findex -fw_cfg
2808 Add named fw_cfg entry from file. @var{name} determines the name of
2809 the entry in the fw_cfg file directory exposed to the guest.
2811 @item -fw_cfg [name=]@var{name},string=@var{str}
2812 Add named fw_cfg entry from string.
2813 ETEXI
2817 QEMU_ARCH_ALL)
2818 STEXI
2819 @item -serial @var{dev}
2820 @findex -serial
2821 Redirect the virtual serial port to host character device
2822 @var{dev}. The default device is @code{vc} in graphical mode and
2823 @code{stdio} in non graphical mode.
2825 This option can be used several times to simulate up to 4 serial
2826 ports.
2828 Use @code{-serial none} to disable all serial ports.
2830 Available character devices are:
2831 @table @option
2832 @item vc[:@var{W}x@var{H}]
2833 Virtual console. Optionally, a width and height can be given in pixel with
2834 @example
2835 vc:800x600
2836 @end example
2837 It is also possible to specify width or height in characters:
2838 @example
2839 vc:80Cx24C
2840 @end example
2841 @item pty
2842 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
2843 @item none
2844 No device is allocated.
2845 @item null
2846 void device
2847 @item chardev:@var{id}
2848 Use a named character device defined with the @code{-chardev} option.
2849 @item /dev/XXX
2850 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
2851 parameters are set according to the emulated ones.
2852 @item /dev/parport@var{N}
2853 [Linux only, parallel port only] Use host parallel port
2854 @var{N}. Currently SPP and EPP parallel port features can be used.
2855 @item file:@var{filename}
2856 Write output to @var{filename}. No character can be read.
2857 @item stdio
2858 [Unix only] standard input/output
2859 @item pipe:@var{filename}
2860 name pipe @var{filename}
2861 @item COM@var{n}
2862 [Windows only] Use host serial port @var{n}
2863 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
2864 This implements UDP Net Console.
2865 When @var{remote_host} or @var{src_ip} are not specified
2866 they default to @code{0.0.0.0}.
2867 When not using a specified @var{src_port} a random port is automatically chosen.
2869 If you just want a simple readonly console you can use @code{netcat} or
2870 @code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
2871 @code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
2872 will appear in the netconsole session.
2874 If you plan to send characters back via netconsole or you want to stop
2875 and start QEMU a lot of times, you should have QEMU use the same
2876 source port each time by using something like @code{-serial
2877 udp::4555@@:4556} to QEMU. Another approach is to use a patched
2878 version of netcat which can listen to a TCP port and send and receive
2879 characters via udp. If you have a patched version of netcat which
2880 activates telnet remote echo and single char transfer, then you can
2881 use the following options to step up a netcat redirector to allow
2882 telnet on port 5555 to access the QEMU port.
2883 @table @code
2884 @item QEMU Options:
2885 -serial udp::4555@@:4556
2886 @item netcat options:
2887 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
2888 @item telnet options:
2889 localhost 5555
2890 @end table
2892 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}]
2893 The TCP Net Console has two modes of operation. It can send the serial
2894 I/O to a location or wait for a connection from a location. By default
2895 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
2896 the @var{server} option QEMU will wait for a client socket application
2897 to connect to the port before continuing, unless the @code{nowait}
2898 option was specified. The @code{nodelay} option disables the Nagle buffering
2899 algorithm. The @code{reconnect} option only applies if @var{noserver} is
2900 set, if the connection goes down it will attempt to reconnect at the
2901 given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only
2902 one TCP connection at a time is accepted. You can use @code{telnet} to
2903 connect to the corresponding character device.
2904 @table @code
2905 @item Example to send tcp console to 192.168.0.2 port 4444
2906 -serial tcp:192.168.0.2:4444
2907 @item Example to listen and wait on port 4444 for connection
2908 -serial tcp::4444,server
2909 @item Example to not wait and listen on ip 192.168.0.100 port 4444
2910 -serial tcp:192.168.0.100:4444,server,nowait
2911 @end table
2913 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
2914 The telnet protocol is used instead of raw tcp sockets. The options
2915 work the same as if you had specified @code{-serial tcp}. The
2916 difference is that the port acts like a telnet server or client using
2917 telnet option negotiation. This will also allow you to send the
2918 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
2919 sequence. Typically in unix telnet you do it with Control-] and then
2922 @item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}]
2923 A unix domain socket is used instead of a tcp socket. The option works the
2924 same as if you had specified @code{-serial tcp} except the unix domain socket
2925 @var{path} is used for connections.
2927 @item mon:@var{dev_string}
2928 This is a special option to allow the monitor to be multiplexed onto
2929 another serial port. The monitor is accessed with key sequence of
2930 @key{Control-a} and then pressing @key{c}.
2931 @var{dev_string} should be any one of the serial devices specified
2932 above. An example to multiplex the monitor onto a telnet server
2933 listening on port 4444 would be:
2934 @table @code
2935 @item -serial mon:telnet::4444,server,nowait
2936 @end table
2937 When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
2938 QEMU any more but will be passed to the guest instead.
2940 @item braille
2941 Braille device. This will use BrlAPI to display the braille output on a real
2942 or fake device.
2944 @item msmouse
2945 Three button serial mouse. Configure the guest to use Microsoft protocol.
2946 @end table
2947 ETEXI
2951 QEMU_ARCH_ALL)
2952 STEXI
2953 @item -parallel @var{dev}
2954 @findex -parallel
2955 Redirect the virtual parallel port to host device @var{dev} (same
2956 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
2957 be used to use hardware devices connected on the corresponding host
2958 parallel port.
2960 This option can be used several times to simulate up to 3 parallel
2961 ports.
2963 Use @code{-parallel none} to disable all parallel ports.
2964 ETEXI
2968 QEMU_ARCH_ALL)
2969 STEXI
2970 @item -monitor @var{dev}
2971 @findex -monitor
2972 Redirect the monitor to host device @var{dev} (same devices as the
2973 serial port).
2974 The default device is @code{vc} in graphical mode and @code{stdio} in
2975 non graphical mode.
2976 Use @code{-monitor none} to disable the default monitor.
2977 ETEXI
2980 QEMU_ARCH_ALL)
2981 STEXI
2982 @item -qmp @var{dev}
2983 @findex -qmp
2984 Like -monitor but opens in 'control' mode.
2985 ETEXI
2988 QEMU_ARCH_ALL)
2989 STEXI
2990 @item -qmp-pretty @var{dev}
2991 @findex -qmp-pretty
2992 Like -qmp but uses pretty JSON formatting.
2993 ETEXI
2997 STEXI
2998 @item -mon [chardev=]name[,mode=readline|control][,default]
2999 @findex -mon
3000 Setup monitor on chardev @var{name}.
3001 ETEXI
3005 QEMU_ARCH_ALL)
3006 STEXI
3007 @item -debugcon @var{dev}
3008 @findex -debugcon
3009 Redirect the debug console to host device @var{dev} (same devices as the
3010 serial port). The debug console is an I/O port which is typically port
3011 0xe9; writing to that I/O port sends output to this device.
3012 The default device is @code{vc} in graphical mode and @code{stdio} in
3013 non graphical mode.
3014 ETEXI
3018 STEXI
3019 @item -pidfile @var{file}
3020 @findex -pidfile
3021 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
3022 from a script.
3023 ETEXI
3027 STEXI
3028 @item -singlestep
3029 @findex -singlestep
3030 Run the emulation in single step mode.
3031 ETEXI
3035 QEMU_ARCH_ALL)
3036 STEXI
3037 @item -S
3038 @findex -S
3039 Do not start CPU at startup (you must type 'c' in the monitor).
3040 ETEXI
3046 QEMU_ARCH_ALL)
3047 STEXI
3048 @item -realtime mlock=on|off
3049 @findex -realtime
3050 Run qemu with realtime features.
3051 mlocking qemu and guest memory can be enabled via @option{mlock=on}
3052 (enabled by default).
3053 ETEXI
3057 STEXI
3058 @item -gdb @var{dev}
3059 @findex -gdb
3060 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
3061 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
3062 stdio are reasonable use case. The latter is allowing to start QEMU from
3063 within gdb and establish the connection via a pipe:
3064 @example
3065 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
3066 @end example
3067 ETEXI
3071 QEMU_ARCH_ALL)
3072 STEXI
3073 @item -s
3074 @findex -s
3075 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
3076 (@pxref{gdb_usage}).
3077 ETEXI
3081 QEMU_ARCH_ALL)
3082 STEXI
3083 @item -d @var{item1}[,...]
3084 @findex -d
3085 Enable logging of specified items. Use '-d help' for a list of log items.
3086 ETEXI
3090 QEMU_ARCH_ALL)
3091 STEXI
3092 @item -D @var{logfile}
3093 @findex -D
3094 Output log in @var{logfile} instead of to stderr
3095 ETEXI
3099 QEMU_ARCH_ALL)
3100 STEXI
3101 @item -L @var{path}
3102 @findex -L
3103 Set the directory for the BIOS, VGA BIOS and keymaps.
3104 ETEXI
3108 STEXI
3109 @item -bios @var{file}
3110 @findex -bios
3111 Set the filename for the BIOS.
3112 ETEXI
3116 STEXI
3117 @item -enable-kvm
3118 @findex -enable-kvm
3119 Enable KVM full virtualization support. This option is only available
3120 if KVM support is enabled when compiling.
3121 ETEXI
3128 QEMU_ARCH_ALL)
3132 QEMU_ARCH_ALL)
3133 STEXI
3134 @item -xen-domid @var{id}
3135 @findex -xen-domid
3136 Specify xen guest domain @var{id} (XEN only).
3137 @item -xen-create
3138 @findex -xen-create
3139 Create domain using xen hypercalls, bypassing xend.
3140 Warning: should not be used when xend is in use (XEN only).
3141 @item -xen-attach
3142 @findex -xen-attach
3143 Attach to existing xen domain.
3144 xend will use this when starting QEMU (XEN only).
3145 ETEXI
3149 STEXI
3150 @item -no-reboot
3151 @findex -no-reboot
3152 Exit instead of rebooting.
3153 ETEXI
3157 STEXI
3158 @item -no-shutdown
3159 @findex -no-shutdown
3160 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
3161 This allows for instance switching to monitor to commit changes to the
3162 disk image.
3163 ETEXI
3168 QEMU_ARCH_ALL)
3169 STEXI
3170 @item -loadvm @var{file}
3171 @findex -loadvm
3172 Start right away with a saved state (@code{loadvm} in monitor)
3173 ETEXI
3175 #ifndef _WIN32
3178 #endif
3179 STEXI
3180 @item -daemonize
3181 @findex -daemonize
3182 Daemonize the QEMU process after initialization. QEMU will not detach from
3183 standard IO until it is ready to receive connections on any of its devices.
3184 This option is a useful way for external programs to launch QEMU without having
3185 to cope with initialization race conditions.
3186 ETEXI
3190 QEMU_ARCH_ALL)
3191 STEXI
3192 @item -option-rom @var{file}
3193 @findex -option-rom
3194 Load the contents of @var{file} as an option ROM.
3195 This option is useful to load things like EtherBoot.
3196 ETEXI
3198 HXCOMM Silently ignored for compatibility
3201 HXCOMM Options deprecated by -rtc
3208 QEMU_ARCH_ALL)
3210 STEXI
3212 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
3213 @findex -rtc
3214 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
3215 UTC or local time, respectively. @code{localtime} is required for correct date in
3216 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
3217 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
3219 By default the RTC is driven by the host system time. This allows using of the
3220 RTC as accurate reference clock inside the guest, specifically if the host
3221 time is smoothly following an accurate external reference clock, e.g. via NTP.
3222 If you want to isolate the guest time from the host, you can set @option{clock}
3223 to @code{rt} instead. To even prevent it from progressing during suspension,
3224 you can set it to @code{vm}.
3226 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
3227 specifically with Windows' ACPI HAL. This option will try to figure out how
3228 many timer interrupts were not processed by the Windows guest and will
3229 re-inject them.
3230 ETEXI
3237 STEXI
3238 @item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename}]
3239 @findex -icount
3240 Enable virtual instruction counter. The virtual cpu will execute one
3241 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
3242 then the virtual cpu speed will be automatically adjusted to keep virtual
3243 time within a few seconds of real time.
3245 When the virtual cpu is sleeping, the virtual time will advance at default
3246 speed unless @option{sleep=no} is specified.
3247 With @option{sleep=no}, the virtual time will jump to the next timer deadline
3248 instantly whenever the virtual cpu goes to sleep mode and will not advance
3249 if no timer is enabled. This behavior give deterministic execution times from
3250 the guest point of view.
3252 Note that while this option can give deterministic behavior, it does not
3253 provide cycle accurate emulation. Modern CPUs contain superscalar out of
3254 order cores with complex cache hierarchies. The number of instructions
3255 executed often has little or no correlation with actual performance.
3257 @option{align=on} will activate the delay algorithm which will try
3258 to synchronise the host clock and the virtual clock. The goal is to
3259 have a guest running at the real frequency imposed by the shift option.
3260 Whenever the guest clock is behind the host clock and if
3261 @option{align=on} is specified then we print a message to the user
3262 to inform about the delay.
3263 Currently this option does not work when @option{shift} is @code{auto}.
3264 Note: The sync algorithm will work for those shift values for which
3265 the guest clock runs ahead of the host clock. Typically this happens
3266 when the shift value is high (how high depends on the host machine).
3268 When @option{rr} option is specified deterministic record/replay is enabled.
3269 Replay log is written into @var{filename} file in record mode and
3270 read from this file in replay mode.
3271 ETEXI
3276 QEMU_ARCH_ALL)
3277 STEXI
3278 @item -watchdog @var{model}
3279 @findex -watchdog
3280 Create a virtual hardware watchdog device. Once enabled (by a guest
3281 action), the watchdog must be periodically polled by an agent inside
3282 the guest or else the guest will be restarted. Choose a model for
3283 which your guest has drivers.
3285 The @var{model} is the model of hardware watchdog to emulate. Use
3286 @code{-watchdog help} to list available hardware models. Only one
3287 watchdog can be enabled for a guest.
3289 The following models may be available:
3290 @table @option
3291 @item ib700
3292 iBASE 700 is a very simple ISA watchdog with a single timer.
3293 @item i6300esb
3294 Intel 6300ESB I/O controller hub is a much more featureful PCI-based
3295 dual-timer watchdog.
3296 @item diag288
3297 A virtual watchdog for s390x backed by the diagnose 288 hypercall
3298 (currently KVM only).
3299 @end table
3300 ETEXI
3305 QEMU_ARCH_ALL)
3306 STEXI
3307 @item -watchdog-action @var{action}
3308 @findex -watchdog-action
3310 The @var{action} controls what QEMU will do when the watchdog timer
3311 expires.
3312 The default is
3313 @code{reset} (forcefully reset the guest).
3314 Other possible actions are:
3315 @code{shutdown} (attempt to gracefully shutdown the guest),
3316 @code{poweroff} (forcefully poweroff the guest),
3317 @code{pause} (pause the guest),
3318 @code{debug} (print a debug message and continue), or
3319 @code{none} (do nothing).
3321 Note that the @code{shutdown} action requires that the guest responds
3322 to ACPI signals, which it may not be able to do in the sort of
3323 situations where the watchdog would have expired, and thus
3324 @code{-watchdog-action shutdown} is not recommended for production use.
3326 Examples:
3328 @table @code
3329 @item -watchdog i6300esb -watchdog-action pause
3330 @itemx -watchdog ib700
3331 @end table
3332 ETEXI
3336 QEMU_ARCH_ALL)
3337 STEXI
3339 @item -echr @var{numeric_ascii_value}
3340 @findex -echr
3341 Change the escape character used for switching to the monitor when using
3342 monitor and serial sharing. The default is @code{0x01} when using the
3343 @code{-nographic} option. @code{0x01} is equal to pressing
3344 @code{Control-a}. You can select a different character from the ascii
3345 control keys where 1 through 26 map to Control-a through Control-z. For
3346 instance you could use the either of the following to change the escape
3347 character to Control-t.
3348 @table @code
3349 @item -echr 0x14
3350 @itemx -echr 20
3351 @end table
3352 ETEXI
3357 STEXI
3358 @item -virtioconsole @var{c}
3359 @findex -virtioconsole
3360 Set virtio console.
3362 This option is maintained for backward compatibility.
3364 Please use @code{-device virtconsole} for the new way of invocation.
3365 ETEXI
3369 STEXI
3370 @item -show-cursor
3371 @findex -show-cursor
3372 Show cursor.
3373 ETEXI
3377 STEXI
3378 @item -tb-size @var{n}
3379 @findex -tb-size
3380 Set TB size.
3381 ETEXI
3395 QEMU_ARCH_ALL)
3396 STEXI
3397 @item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6]
3398 @itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6]
3399 @findex -incoming
3400 Prepare for incoming migration, listen on a given tcp port.
3402 @item -incoming unix:@var{socketpath}
3403 Prepare for incoming migration, listen on a given unix socket.
3405 @item -incoming fd:@var{fd}
3406 Accept incoming migration from a given filedescriptor.
3408 @item -incoming exec:@var{cmdline}
3409 Accept incoming migration as an output from specified external command.
3411 @item -incoming defer
3412 Wait for the URI to be specified via migrate_incoming. The monitor can
3413 be used to change settings (such as migration parameters) prior to issuing
3414 the migrate_incoming to allow the migration to begin.
3415 ETEXI
3419 STEXI
3420 @item -nodefaults
3421 @findex -nodefaults
3426 ETEXI
3428 #ifndef _WIN32
3431 QEMU_ARCH_ALL)
3432 #endif
3433 STEXI
3435 @findex -chroot
3436 Immediately before starting guest execution, chroot to the specified
3438 ETEXI
3440 #ifndef _WIN32
3443 QEMU_ARCH_ALL)
3444 #endif
3445 STEXI
3447 @findex -runas
3449 to the specified user.
3450 ETEXI
3455 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3456 STEXI
3460 ETEXI
3463 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3464 QEMU_ARCH_MIPS)
3465 STEXI
3466 @item -semihosting
3467 @findex -semihosting
3469 ETEXI
3473 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3474 QEMU_ARCH_MIPS)
3475 STEXI
3479 @table @option
3485 Allows the user to pass input arguments, and can be used multiple times to build
3490 @end table
3491 ETEXI
3494 STEXI
3498 ETEXI
3502 QEMU_ARCH_ALL)
3503 STEXI
3505 @findex -sandbox
3508 ETEXI
3512 STEXI
3514 @findex -readconfig
3516 QEMU process with many command line options but you don't want to exceed the command line
3517 character limit.
3518 ETEXI
3519 DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
3522 STEXI
3523 @item -writeconfig @var{file}
3524 @findex -writeconfig
3525 Write device configuration to @var{file}. The @var{file} can be either filename to save
3526 command line and device configuration into file or dash @code{-}) character to print the
3527 output to stdout. This can be later used as input file for @code{-readconfig} option.
3528 ETEXI
3529 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig,
3532 QEMU_ARCH_ALL)
3533 STEXI
3534 @item -nodefconfig
3535 @findex -nodefconfig
3536 Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
3537 The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
3538 ETEXI
3539 DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
3542 QEMU_ARCH_ALL)
3543 STEXI
3544 @item -no-user-config
3545 @findex -no-user-config
3546 The @code{-no-user-config} option makes QEMU not load any of the user-provided
3549 ETEXI
3553 QEMU_ARCH_ALL)
3554 STEXI
3556 HXCOMM HX does not support conditional compilation of text.
3560 Specify tracing options.
3562 @table @option
3582 This option is only available if QEMU has been compiled with
3584 @end table
3585 ETEXI
3587 HXCOMM Internal use
3591 #ifdef __linux__
3594 QEMU_ARCH_ALL)
3595 #endif
3596 STEXI
3600 ETEXI
3605 HXCOMM Deprecated by kvm-pit driver properties
3622 QEMU_ARCH_ALL)
3623 STEXI
3625 @findex -msg
3627 ETEXI
3635 QEMU_ARCH_ALL)
3636 STEXI
3641 ETEXI
3651 QEMU_ARCH_ALL)
3652 STEXI
3654 @findex -object
3660 @table @option
3662 @item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off}
3664 Creates a memory file backend object, which can be used to back
3666 unique ID that will be used to reference this memory region
3668 option provides the size of the memory region, and accepts
3670 the path to either a shared memory or huge page filesystem mount.
3677 Creates a random number generator backend which obtains entropy from
3685 Creates a random number generator backend which obtains entropy from
3687 a unique ID that will be used to reference this entropy backend from
3689 the unique ID of a character device backend that provides the connection
3690 to the RNG daemon.
3692 @item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off}
3694 Creates a TLS anonymous credentials object, which can be used to provide
3696 ID which network backends will use to access the credentials. The
3698 on whether the QEMU network backend that uses the credentials will be
3707 a set of DH parameters at startup. This is a computationally
3708 expensive operation that consumes random pool entropy, so it is
3709 recommended that a persistent set of parameters be generated
3710 upfront and saved.
3712 @item -object tls-creds-x509,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off},passwordid=@var{id}
3714 Creates a TLS anonymous credentials object, which can be used to provide
3716 ID which network backends will use to access the credentials. The
3718 on whether the QEMU network backend that uses the credentials will be
3722 must be provided with valid client certificates too.
3728 a set of DH parameters at startup. This is a computationally
3729 expensive operation that consumes random pool entropy, so it is
3730 recommended that a persistent set of parameters be generated
3731 upfront and saved.
3733 For x509 certificate credentials the directory will contain further files
3734 providing the x509 certificates. The certificates must be stored
3745 @item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}]
3748 packets arriving in a given interval on netdev @var{netdevid} are delayed
3749 until the end of the interval. Interval is in microseconds.
3751 queue @var{all|rx|tx} is an option that can be applied to any netfilter.
3753 @option{all}: the filter is attached both to the receive and the transmit
3754 queue of the netdev (default).
3756 @option{rx}: the filter is attached to the receive queue of the netdev,
3757 where it will receive packets sent to the netdev.
3759 @option{tx}: the filter is attached to the transmit queue of the netdev,
3760 where it will receive packets sent by the netdev.
3762 @item -object filter-dump,id=@var{id},netdev=@var{dev},file=@var{filename}][,maxlen=@var{len}]
3764 Dump the network traffic on netdev @var{dev} to the file specified by
3765 @var{filename}. At most @var{len} bytes (64k by default) per packet are stored.
3766 The file format is libpcap, so it can be analyzed with tools such as tcpdump
3767 or Wireshark.
3769 @item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
3770 @item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
3772 Defines a secret to store a password, encryption key, or some other sensitive
3773 data. The sensitive data can either be passed directly via the @var{data}
3774 parameter, or indirectly via the @var{file} parameter. Using the @var{data}
3775 parameter is insecure unless the sensitive data is encrypted.
3777 The sensitive data can be provided in raw format (the default), or base64.
3778 When encoded as JSON, the raw format only supports valid UTF-8 characters,
3779 so base64 is recommended for sending binary data. QEMU will convert from
3780 which ever format is provided to the format it needs internally. eg, an
3781 RBD password can be provided in raw format, even though it will be base64
3782 encoded when passed onto the RBD sever.
3784 For added protection, it is possible to encrypt the data associated with
3785 a secret using the AES-256-CBC cipher. Use of encryption is indicated
3786 by providing the @var{keyid} and @var{iv} parameters. The @var{keyid}
3787 parameter provides the ID of a previously defined secret that contains
3788 the AES-256 decryption key. This key should be 32-bytes long and be
3789 base64 encoded. The @var{iv} parameter provides the random initialization
3790 vector used for encryption of this particular secret and should be a
3791 base64 encrypted string of the 32-byte IV.
3793 The simplest (insecure) usage is to provide the secret inline
3795 @example
3797 # $QEMU -object secret,id=sec0,data=letmein,format=raw
3799 @end example
3801 The simplest secure usage is to provide the secret via a file
3803 # echo -n "letmein" > mypasswd.txt
3804 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw
3806 For greater security, AES-256-CBC should be used. To illustrate usage,
3807 consider the openssl command line tool which can encrypt the data. Note
3808 that when encrypting, the plaintext must be padded to the cipher block
3809 size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm.
3811 First a master key needs to be created in base64 encoding:
3813 @example
3814 # openssl rand -base64 32 > key.b64
3816 @end example
3818 Each secret to be encrypted needs to have a random initialization vector
3819 generated. These do not need to be kept secret
3821 @example
3822 # openssl rand -base64 16 > iv.b64
3824 @end example
3826 The secret to be defined can now be encrypted, in this case we're
3827 telling openssl to base64 encode the result, but it could be left
3830 @example
3833 @end example
3836 and specify that to be used to decrypt the user password. Pass the
3839 @example
3840 # $QEMU \
3844 @end example
3846 @end table
3848 ETEXI
3852 STEXI
3853 @end table
3854 ETEXI