| blob | c534a2f7f9c617330cfaf4ac89499ba5da6976a7 |
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.
77 controls whether AES wrapping keys will be created to allow
81 controls whether DEA wrapping keys will be created to allow
83 @item nvdimm=on|off
85 @end table
86 ETEXI
88 HXCOMM Deprecated by -machine
93 STEXI
95 @findex -cpu
97 ETEXI
107 QEMU_ARCH_ALL)
108 STEXI
109 @item -smp [cpus=]@var{n}[,cores=@var{cores}][,threads=@var{threads}][,sockets=@var{sockets}][,maxcpus=@var{maxcpus}]
110 @findex -smp
118 specifies the maximum number of hotpluggable CPUs.
119 ETEXI
124 STEXI
127 @findex -numa
131 resources. That is, it just assigns existing resources to NUMA nodes. This
132 means that one still has to use the @option{-m}, @option{-smp} options
133 to allocate RAM and VCPUs respectively, and possibly @option{-object}
134 to specify the memory backend for the @samp{memdev} suboption.
136 @samp{mem} and @samp{memdev} are mutually exclusive. Furthermore, if one
137 node uses @samp{memdev}, all of them have to use it.
138 ETEXI
140 DEF("add-fd", HAS_ARG, QEMU_OPTION_add_fd,
143 STEXI
144 @item -add-fd fd=@var{fd},set=@var{set}[,opaque=@var{opaque}]
145 @findex -add-fd
147 Add a file descriptor to an fd set. Valid options are:
149 @table @option
150 @item fd=@var{fd}
151 This option defines the file descriptor of which a duplicate is added to fd set.
152 The file descriptor cannot be stdin, stdout, or stderr.
153 @item set=@var{set}
154 This option defines the ID of the fd set to add the file descriptor to.
155 @item opaque=@var{opaque}
156 This option defines a free-form string that can be used to describe @var{fd}.
157 @end table
159 You can open an image using pre-opened file descriptors from an fd set:
160 @example
161 qemu-system-i386
162 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
163 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
164 -drive file=/dev/fdset/2,index=0,media=disk
165 @end example
166 ETEXI
168 DEF("set", HAS_ARG, QEMU_OPTION_set,
172 STEXI
173 @item -set @var{group}.@var{id}.@var{arg}=@var{value}
174 @findex -set
175 Set parameter @var{arg} for item @var{id} of type @var{group}
176 ETEXI
178 DEF("global", HAS_ARG, QEMU_OPTION_global,
182 QEMU_ARCH_ALL)
183 STEXI
184 @item -global @var{driver}.@var{prop}=@var{value}
185 @itemx -global driver=@var{driver},property=@var{property},value=@var{value}
186 @findex -global
189 @example
190 qemu-system-i386 -global ide-drive.physical_block_size=4096 -drive file=file,if=ide,index=0,media=disk
191 @end example
194 created automatically by the machine model. To create a device which is not
200 ETEXI
209 QEMU_ARCH_ALL)
210 STEXI
211 @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]
212 @findex -boot
217 particular boot order only on the first startup, specify it via
233 system support it.
236 supports it. This only effects when boot priority is changed by
239 @example
246 @end example
249 use is discouraged as it may be removed from future versions.
250 ETEXI
259 QEMU_ARCH_ALL)
260 STEXI
262 @findex -m
266 could be used to set amount of hotpluggable memory slots and maximum amount of
273 @example
275 @end example
278 be enabled and the guest startup RAM will never increase.
279 ETEXI
281 DEF("mem-path", HAS_ARG, QEMU_OPTION_mempath,
283 STEXI
284 @item -mem-path @var{path}
285 @findex -mem-path
286 Allocate guest RAM from a temporarily created file in @var{path}.
287 ETEXI
289 DEF("mem-prealloc", 0, QEMU_OPTION_mem_prealloc,
291 QEMU_ARCH_ALL)
292 STEXI
293 @item -mem-prealloc
294 @findex -mem-prealloc
295 Preallocate memory when using -mem-path.
296 ETEXI
298 DEF("k", HAS_ARG, QEMU_OPTION_k,
300 QEMU_ARCH_ALL)
301 STEXI
302 @item -k @var{language}
303 @findex -k
304 Use keyboard layout @var{language} (for example @code{fr} for
305 French). This option is only needed where it is not easy to get raw PC
306 keycodes (e.g. on Macs, with some X11 servers or with a VNC or curses
308 hosts.
310 The available layouts are:
311 @example
315 @end example
318 ETEXI
323 QEMU_ARCH_ALL)
324 STEXI
328 parameters.
329 ETEXI
336 STEXI
338 @findex -soundhw
340 available sound hardware.
342 @example
349 @end example
351 Note that Linux's i810_audio OSS kernel (for AC97) module might
352 require manually specifying clocking.
354 @example
355 modprobe i810_audio clocking=48000
356 @end example
357 ETEXI
359 DEF("balloon", HAS_ARG, QEMU_OPTION_balloon,
363 STEXI
364 @item -balloon none
365 @findex -balloon
366 Disable balloon device.
367 @item -balloon virtio[,addr=@var{addr}]
368 Enable virtio balloon device (default), optionally with PCI address
369 @var{addr}.
370 ETEXI
372 DEF("device", HAS_ARG, QEMU_OPTION_device,
378 QEMU_ARCH_ALL)
379 STEXI
380 @item -device @var{driver}[,@var{prop}[=@var{value}][,...]]
381 @findex -device
382 Add device @var{driver}. @var{prop}=@var{value} sets driver
383 properties. Valid properties depend on the driver. To get help on
384 possible drivers and properties, use @code{-device help} and
385 @code{-device @var{driver},help}.
387 Some drivers are:
388 @item -device ipmi-bmc-sim,id=@var{id}[,slave_addr=@var{val}]
390 Add an IPMI BMC. This is a simulation of a hardware management
391 interface processor that normally sits on a system. It provides
392 a watchdog and the ability to reset and power control the system.
393 You need to connect this to an IPMI interface to make it useful
395 The IPMI slave address to use for the BMC. The default is 0x20.
396 This address is the BMC's address on the I2C network of management
398 it.
400 @item -device ipmi-bmc-extern,id=@var{id},chardev=@var{id}[,slave_addr=@var{val}]
402 Add a connection to an external IPMI BMC simulator. Instead of
403 locally emulating the BMC like the above item, instead connect
404 to an external entity that provides the IPMI services.
406 A connection is made to an external BMC simulator. If you do this, it
407 is strongly recommended that you use the "reconnect=" chardev option
408 to reconnect to the simulator if the connection is lost. Note that if
409 this is not used carefully, it can be a security issue, as the
410 interface has the ability to send resets, NMIs, and power off the VM.
412 on a secure port on localhost, so neither the simulator nor QEMU is
413 exposed to any outside network.
420 Add a KCS IPMI interafce on the ISA bus. This also adds a
423 @table @option
431 @end table
438 ETEXI
446 QEMU_ARCH_ALL)
447 STEXI
449 @findex -name
454 Naming of individual threads can also be enabled on Linux to aid debugging.
455 ETEXI
460 STEXI
462 @findex -uuid
463 Set system UUID.
464 ETEXI
466 STEXI
467 @end table
468 ETEXI
472 STEXI
473 @table @option
474 ETEXI
479 STEXI
482 @findex -fda
483 @findex -fdb
485 ETEXI
493 STEXI
498 @findex -hda
499 @findex -hdb
500 @findex -hdc
501 @findex -hdd
503 ETEXI
507 QEMU_ARCH_ALL)
508 STEXI
510 @findex -cdrom
514 ETEXI
531 STEXI
533 @findex -drive
537 @table @option
543 Special files such as iSCSI devices can be specified using protocol
549 These options define where is connected the drive by defining the bus number and
550 the unit id.
562 @var{cache} is "none", "writeback", "unsafe", "directsync" or "writethrough" and controls how the host cache is used to access block data.
564 @var{aio} is "threads", or "native" and selects between pthread based disk I/O and native Linux AIO.
566 @var{discard} is one of "ignore" (or "off") or "unmap" (or "on") and controls whether @dfn{discard} (also known as @dfn{trim} or @dfn{unmap}) requests are ignored or passed to the filesystem. Some machine types may not support discard requests.
570 an untrusted format header.
572 This option specifies the serial number to assign to the device.
574 Specify the controller's PCI address (if=virtio only).
575 @item werror=@var{action},rerror=@var{action}
576 Specify which @var{action} to take on write and read errors. Valid actions are:
577 "ignore" (ignore the error and try to continue), "stop" (pause QEMU),
578 "report" (report the error to the guest), "enospc" (pause QEMU only if the
579 host disk is full; report the error to the guest otherwise).
580 The default setting is @option{werror=enospc} and @option{rerror=report}.
581 @item readonly
582 Open drive @option{file} as read-only. Guest write attempts will fail.
583 @item copy-on-read=@var{copy-on-read}
584 @var{copy-on-read} is "on" or "off" and enables whether to copy read backing
585 file sectors into the image file.
586 @item detect-zeroes=@var{detect-zeroes}
587 @var{detect-zeroes} is "off", "on" or "unmap" and enables the automatic
588 conversion of plain zero writes by the OS to driver specific optimized
589 zero write commands. You may even choose "unmap" if @var{discard} is set
590 to "unmap" to allow a zero write to be converted to an UNMAP operation.
591 @end table
593 By default, the @option{cache=writeback} mode is used. It will report data
594 writes as completed as soon as the data is present in the host page cache.
595 This is safe as long as your guest OS makes sure to correctly flush disk caches
596 where needed. If your guest OS does not handle volatile disk write caches
597 correctly and your host crashes or loses power, then the guest may experience
598 data corruption.
600 For such guests, you should consider using @option{cache=writethrough}. This
601 means that the host page cache will be used to read and write data, but write
602 notification will be sent to the guest only after QEMU has made sure to flush
603 each write to the disk. Be aware that this has a major impact on performance.
605 The host page cache can be avoided entirely with @option{cache=none}. This will
608 the guest OS must handle the disk write cache correctly in order to avoid data
609 corruption on host crashes.
611 The host page cache can be avoided while only sending write notifications to
612 the guest when the data has been flushed to the disk using
616 @option{cache=unsafe}. This option tells QEMU that it never needs to write any
617 data to the disk but can instead keep things in cache. If anything goes wrong,
618 like your host losing power, the disk storage getting disconnected accidentally,
619 etc. your image will most probably be rendered unusable. When using
620 the @option{-snapshot} option, unsafe caching is always used.
622 Copy-on-read avoids accessing the same backing file sectors repeatedly and is
623 useful when the backing file is over a slow network. By default copy-on-read
624 is off.
626 Instead of @option{-cdrom} you can use:
627 @example
628 qemu-system-i386 -drive file=file,index=2,media=cdrom
629 @end example
631 Instead of @option{-hda}, @option{-hdb}, @option{-hdc}, @option{-hdd}, you can
632 use:
633 @example
634 qemu-system-i386 -drive file=file,index=0,media=disk
635 qemu-system-i386 -drive file=file,index=1,media=disk
636 qemu-system-i386 -drive file=file,index=2,media=disk
637 qemu-system-i386 -drive file=file,index=3,media=disk
638 @end example
640 You can open an image using pre-opened file descriptors from an fd set:
641 @example
642 qemu-system-i386
643 -add-fd fd=3,set=2,opaque="rdwr:/path/to/file"
644 -add-fd fd=4,set=2,opaque="rdonly:/path/to/file"
645 -drive file=/dev/fdset/2,index=0,media=disk
646 @end example
648 You can connect a CDROM to the slave of ide0:
649 @example
650 qemu-system-i386 -drive file=file,if=ide,index=1,media=cdrom
651 @end example
654 @example
656 @end example
659 @example
661 @end example
664 @example
667 @end example
670 incremented:
671 @example
673 @end example
674 is interpreted like:
675 @example
676 qemu-system-i386 -hda a -hdb b
677 @end example
678 ETEXI
682 QEMU_ARCH_ALL)
683 STEXI
684 @item -mtdblock @var{file}
685 @findex -mtdblock
686 Use @var{file} as on-board Flash memory image.
687 ETEXI
691 STEXI
692 @item -sd @var{file}
693 @findex -sd
694 Use @var{file} as SecureDigital card image.
695 ETEXI
699 STEXI
700 @item -pflash @var{file}
701 @findex -pflash
702 Use @var{file} as a parallel flash image.
703 ETEXI
707 QEMU_ARCH_ALL)
708 STEXI
709 @item -snapshot
710 @findex -snapshot
711 Write to temporary files instead of disk image files. In this case,
712 the raw disk image you use is not written back. You can however force
713 the write back by pressing @key{C-a s} (@pxref{disk_images}).
714 ETEXI
720 QEMU_ARCH_ALL)
721 STEXI
722 @item -hdachs @var{c},@var{h},@var{s},[,@var{t}]
723 @findex -hdachs
724 Force hard disk 0 physical geometry (1 <= @var{c} <= 16383, 1 <=
725 @var{h} <= 16, 1 <= @var{s} <= 63) and optionally force the BIOS
726 translation mode (@var{t}=none, lba or auto). Usually QEMU can guess
727 all those parameters. This option is useful for old MS-DOS disk
728 images.
729 ETEXI
732 "-fsdev fsdriver,id=id[,path=path,][security_model={mapped-xattr|mapped-file|passthrough|none}]\n"
734 QEMU_ARCH_ALL)
736 STEXI
738 @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}]
739 @findex -fsdev
740 Define a new file system device. Valid options are:
741 @table @option
742 @item @var{fsdriver}
743 This option specifies the fs driver backend to use.
745 @item id=@var{id}
746 Specifies identifier for this device
747 @item path=@var{path}
748 Specifies the export path for the file system device. Files under
749 this path will be available to the 9p client on the guest.
750 @item security_model=@var{security_model}
751 Specifies the security model to be used for this export path.
754 credentials as they are created on the guest. This requires QEMU
756 attributes like uid, gid, mode bits and link target are stored as
758 hidden .virtfs_metadata directory. Directories exported by this security model cannot
760 passthrough except the sever won't report failures if it fails to
761 set file attributes like ownership. Security model is mandatory
762 only for local fsdriver. Other fsdrivers (like handle, proxy) don't take
763 security model as a parameter.
764 @item writeout=@var{writeout}
766 This means that host page cache will be used to read and write data but
767 write notification will be sent to the guest only when the data has been
768 reported as written by the storage subsystem.
769 @item readonly
770 Enables exporting 9p share as a readonly mount for guests. By default
771 read-write access is given.
772 @item socket=@var{socket}
773 Enables proxy filesystem driver to use passed socket file for communicating
774 with virtfs-proxy-helper
775 @item sock_fd=@var{sock_fd}
776 Enables proxy filesystem driver to use passed socket descriptor for
777 communicating with virtfs-proxy-helper. Usually a helper like libvirt
778 will create socketpair and pass one of the fds as sock_fd
779 @end table
782 @item -device virtio-9p-pci,fsdev=@var{id},mount_tag=@var{mount_tag}
783 Options for virtio-9p-pci driver are:
784 @table @option
785 @item fsdev=@var{id}
786 Specifies the id value specified along with -fsdev option
787 @item mount_tag=@var{mount_tag}
788 Specifies the tag name to be used by the guest to mount this export point
789 @end table
791 ETEXI
794 "-virtfs local,path=path,mount_tag=tag,security_model=[mapped-xattr|mapped-file|passthrough|none]\n"
796 QEMU_ARCH_ALL)
798 STEXI
800 @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}]
801 @findex -virtfs
803 The general form of a Virtual File system pass-through options are:
804 @table @option
805 @item @var{fsdriver}
806 This option specifies the fs driver backend to use.
808 @item id=@var{id}
809 Specifies identifier for this device
810 @item path=@var{path}
811 Specifies the export path for the file system device. Files under
812 this path will be available to the 9p client on the guest.
813 @item security_model=@var{security_model}
814 Specifies the security model to be used for this export path.
817 credentials as they are created on the guest. This requires QEMU
819 attributes like uid, gid, mode bits and link target are stored as
821 hidden .virtfs_metadata directory. Directories exported by this security model cannot
823 passthrough except the sever won't report failures if it fails to
824 set file attributes like ownership. Security model is mandatory only
825 for local fsdriver. Other fsdrivers (like handle, proxy) don't take security
826 model as a parameter.
827 @item writeout=@var{writeout}
829 This means that host page cache will be used to read and write data but
830 write notification will be sent to the guest only when the data has been
831 reported as written by the storage subsystem.
832 @item readonly
833 Enables exporting 9p share as a readonly mount for guests. By default
834 read-write access is given.
835 @item socket=@var{socket}
836 Enables proxy filesystem driver to use passed socket file for
837 communicating with virtfs-proxy-helper. Usually a helper like libvirt
838 will create socketpair and pass one of the fds as sock_fd
839 @item sock_fd
840 Enables proxy filesystem driver to use passed 'sock_fd' as the socket
841 descriptor for interfacing with virtfs-proxy-helper
842 @end table
843 ETEXI
847 QEMU_ARCH_ALL)
848 STEXI
849 @item -virtfs_synth
850 @findex -virtfs_synth
851 Create synthetic file system image
852 ETEXI
854 STEXI
855 @end table
856 ETEXI
857 DEFHEADING()
859 DEFHEADING(USB options:)
860 STEXI
861 @table @option
862 ETEXI
866 QEMU_ARCH_ALL)
867 STEXI
868 @item -usb
869 @findex -usb
870 Enable the USB driver (will be the default soon)
871 ETEXI
875 QEMU_ARCH_ALL)
876 STEXI
878 @item -usbdevice @var{devname}
879 @findex -usbdevice
880 Add the USB device @var{devname}. @xref{usb_devices}.
882 @table @option
884 @item mouse
885 Virtual Mouse. This will override the PS/2 mouse emulation when activated.
887 @item tablet
888 Pointer device that uses absolute coordinates (like a touchscreen). This
889 means QEMU is able to report the mouse position without having to grab the
890 mouse. Also overrides the PS/2 mouse emulation when activated.
892 @item disk:[format=@var{format}]:@var{file}
893 Mass storage device based on file. The optional @var{format} argument
894 will be used rather than detecting the format. Can be used to specify
895 @code{format=raw} to avoid interpreting an untrusted format header.
897 @item host:@var{bus}.@var{addr}
898 Pass through the host device identified by @var{bus}.@var{addr} (Linux only).
900 @item host:@var{vendor_id}:@var{product_id}
901 Pass through the host device identified by @var{vendor_id}:@var{product_id}
902 (Linux only).
904 @item serial:[vendorid=@var{vendor_id}][,productid=@var{product_id}]:@var{dev}
905 Serial converter to host character device @var{dev}, see @code{-serial} for the
906 available devices.
908 @item braille
909 Braille device. This will use BrlAPI to display the braille output on a real
910 or fake device.
912 @item net:@var{options}
913 Network adapter that supports CDC ethernet and RNDIS protocols.
915 @end table
916 ETEXI
918 STEXI
919 @end table
920 ETEXI
921 DEFHEADING()
923 DEFHEADING(Display options:)
924 STEXI
925 @table @option
926 ETEXI
937 #if defined(CONFIG_GTK)
939 #elif defined(CONFIG_SDL)
941 #elif defined(CONFIG_COCOA)
943 #elif defined(CONFIG_VNC)
945 #else
947 #endif
948 , QEMU_ARCH_ALL)
949 STEXI
950 @item -display @var{type}
951 @findex -display
952 Select type of display to use. This option is a replacement for the
953 old style -sdl/-curses/... options. Valid values for @var{type} are
954 @table @option
955 @item sdl
956 Display video output via SDL (usually in a separate graphics
957 window; see the SDL documentation for other possibilities).
958 @item curses
959 Display video output via curses. For graphics device models which
960 support a text mode, QEMU can display this output using a
961 curses/ncurses interface. Nothing is displayed when the graphics
962 device is in graphical mode or if the graphics device does not support
963 a text mode. Generally only the VGA device models support text mode.
964 @item none
965 Do not display video output. The guest will still see an emulated
966 graphics card, but its output will not be displayed to the QEMU
967 user. This option differs from the -nographic option in that it
968 only affects what is done with video output; -nographic also changes
969 the destination of the serial and parallel port data.
970 @item gtk
971 Display video output in a GTK window. This interface provides drop-down
972 menus and other UI elements to configure and control the VM during
973 runtime.
974 @item vnc
975 Start a VNC server on display <arg>
976 @end table
977 ETEXI
981 QEMU_ARCH_ALL)
982 STEXI
983 @item -nographic
984 @findex -nographic
985 Normally, if QEMU is compiled with graphical window support, it displays
986 output such as guest graphics, guest console, and the QEMU monitor in a
987 window. With this option, you can totally disable graphical output so
988 that QEMU is a simple command line application. The emulated serial port
989 is redirected on the console and muxed with the monitor (unless
990 redirected elsewhere explicitly). Therefore, you can still use QEMU to
991 debug a Linux kernel with a serial console. Use @key{C-a h} for help on
992 switching between the console and monitor.
993 ETEXI
997 QEMU_ARCH_ALL)
998 STEXI
999 @item -curses
1000 @findex -curses
1001 Normally, if QEMU is compiled with graphical window support, it displays
1002 output such as guest graphics, guest console, and the QEMU monitor in a
1003 window. With this option, QEMU can display the VGA output when in text
1004 mode using a curses/ncurses interface. Nothing is displayed in graphical
1005 mode.
1006 ETEXI
1010 QEMU_ARCH_ALL)
1011 STEXI
1012 @item -no-frame
1013 @findex -no-frame
1014 Do not use decorations for SDL windows and start them using the whole
1015 available screen space. This makes the using QEMU in a dedicated desktop
1016 workspace more convenient.
1017 ETEXI
1021 QEMU_ARCH_ALL)
1022 STEXI
1023 @item -alt-grab
1024 @findex -alt-grab
1025 Use Ctrl-Alt-Shift to grab mouse (instead of Ctrl-Alt). Note that this also
1026 affects the special keys (for fullscreen, monitor-mode switching, etc).
1027 ETEXI
1031 QEMU_ARCH_ALL)
1032 STEXI
1033 @item -ctrl-grab
1034 @findex -ctrl-grab
1035 Use Right-Ctrl to grab mouse (instead of Ctrl-Alt). Note that this also
1036 affects the special keys (for fullscreen, monitor-mode switching, etc).
1037 ETEXI
1041 STEXI
1042 @item -no-quit
1043 @findex -no-quit
1044 Disable SDL window close capability.
1045 ETEXI
1049 STEXI
1050 @item -sdl
1051 @findex -sdl
1052 Enable SDL.
1053 ETEXI
1073 QEMU_ARCH_ALL)
1074 STEXI
1075 @item -spice @var{option}[,@var{option}[,...]]
1076 @findex -spice
1077 Enable the spice remote desktop protocol. Valid options are
1079 @table @option
1081 @item port=<nr>
1082 Set the TCP port spice is listening on for plaintext channels.
1084 @item addr=<addr>
1085 Set the IP address spice is listening on. Default is any address.
1087 @item ipv4
1088 @itemx ipv6
1089 @itemx unix
1090 Force using the specified IP version.
1092 @item password=<secret>
1093 Set the password you need to authenticate.
1095 @item sasl
1096 Require that the client use SASL to authenticate with the spice.
1097 The exact choice of authentication method used is controlled from the
1098 system / user's SASL configuration file for the 'qemu' service. This
1099 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1100 unprivileged user, an environment variable SASL_CONF_PATH can be used
1101 to make it search alternate locations for the service config.
1102 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1103 it is recommended that SASL always be combined with the 'tls' and
1104 'x509' settings to enable use of SSL and server certificates. This
1105 ensures a data encryption preventing compromise of authentication
1106 credentials.
1108 @item disable-ticketing
1109 Allow client connects without authentication.
1111 @item disable-copy-paste
1112 Disable copy paste between the client and the guest.
1114 @item disable-agent-file-xfer
1115 Disable spice-vdagent based file-xfer between the client and the guest.
1117 @item tls-port=<nr>
1118 Set the TCP port spice is listening on for encrypted channels.
1120 @item x509-dir=<dir>
1121 Set the x509 file directory. Expects same filenames as -vnc $display,x509=$dir
1123 @item x509-key-file=<file>
1124 @itemx x509-key-password=<file>
1125 @itemx x509-cert-file=<file>
1126 @itemx x509-cacert-file=<file>
1127 @itemx x509-dh-key-file=<file>
1128 The x509 file names can also be configured individually.
1130 @item tls-ciphers=<list>
1131 Specify which ciphers to use.
1133 @item tls-channel=[main|display|cursor|inputs|record|playback]
1134 @itemx plaintext-channel=[main|display|cursor|inputs|record|playback]
1135 Force specific channel to be used with or without TLS encryption. The
1136 options can be specified multiple times to configure multiple
1138 mode. For channels which are not explicitly forced into one mode the
1139 spice client is allowed to pick tls/plaintext as he pleases.
1141 @item image-compression=[auto_glz|auto_lz|quic|glz|lz|off]
1142 Configure image compression (lossless).
1143 Default is auto_glz.
1145 @item jpeg-wan-compression=[auto|never|always]
1146 @itemx zlib-glz-wan-compression=[auto|never|always]
1147 Configure wan image compression (lossy for slow links).
1148 Default is auto.
1150 @item streaming-video=[off|all|filter]
1151 Configure video stream detection. Default is off.
1153 @item agent-mouse=[on|off]
1154 Enable/disable passing mouse events via vdagent. Default is on.
1156 @item playback-compression=[on|off]
1157 Enable/disable audio stream compression (using celt 0.5.1). Default is on.
1159 @item seamless-migration=[on|off]
1160 Enable/disable spice seamless migration. Default is off.
1162 @item gl=[on|off]
1163 Enable/disable OpenGL context. Default is off.
1165 @end table
1166 ETEXI
1170 QEMU_ARCH_ALL)
1171 STEXI
1172 @item -portrait
1173 @findex -portrait
1174 Rotate graphical output 90 deg left (only PXA LCD).
1175 ETEXI
1179 QEMU_ARCH_ALL)
1180 STEXI
1181 @item -rotate @var{deg}
1182 @findex -rotate
1183 Rotate graphical output some deg left (only PXA LCD).
1184 ETEXI
1189 STEXI
1190 @item -vga @var{type}
1191 @findex -vga
1192 Select type of VGA card to emulate. Valid values for @var{type} are
1193 @table @option
1194 @item cirrus
1195 Cirrus Logic GD5446 Video card. All Windows versions starting from
1196 Windows 95 should recognize and use this graphic card. For optimal
1197 performances, use 16 bit color depth in the guest and the host OS.
1198 (This one is the default)
1199 @item std
1200 Standard VGA card with Bochs VBE extensions. If your guest OS
1201 supports the VESA 2.0 VBE extensions (e.g. Windows XP) and if you want
1202 to use high resolution modes (>= 1280x1024x16) then you should use
1203 this option.
1204 @item vmware
1205 VMWare SVGA-II compatible adapter. Use it if you have sufficiently
1206 recent XFree86/XOrg server or Windows guest with a driver for this
1207 card.
1208 @item qxl
1209 QXL paravirtual graphic card. It is VGA compatible (including VESA
1210 2.0 VBE support). Works best with qxl guest drivers installed though.
1211 Recommended choice when using the spice protocol.
1212 @item tcx
1213 (sun4m only) Sun TCX framebuffer. This is the default framebuffer for
1214 sun4m machines and offers both 8-bit and 24-bit colour depths at a
1215 fixed resolution of 1024x768.
1216 @item cg3
1217 (sun4m only) Sun cgthree framebuffer. This is a simple 8-bit framebuffer
1218 for sun4m machines available in both 1024x768 (OpenBIOS) and 1152x900 (OBP)
1219 resolutions aimed at people wishing to run older Solaris versions.
1220 @item virtio
1221 Virtio VGA card.
1222 @item none
1223 Disable VGA card.
1224 @end table
1225 ETEXI
1229 STEXI
1230 @item -full-screen
1231 @findex -full-screen
1232 Start in full screen.
1233 ETEXI
1237 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
1238 STEXI
1239 @item -g @var{width}x@var{height}[x@var{depth}]
1240 @findex -g
1241 Set the initial graphical resolution and depth (PPC, SPARC only).
1242 ETEXI
1246 STEXI
1247 @item -vnc @var{display}[,@var{option}[,@var{option}[,...]]]
1248 @findex -vnc
1249 Normally, if QEMU is compiled with graphical window support, it displays
1250 output such as guest graphics, guest console, and the QEMU monitor in a
1251 window. With this option, you can have QEMU listen on VNC display
1252 @var{display} and redirect the VGA display over the VNC session. It is
1253 very useful to enable the usb tablet device when using this option
1254 (option @option{-usbdevice tablet}). When using the VNC display, you
1255 must use the @option{-k} parameter to set the keyboard layout if you are
1256 not using en-us. Valid syntax for the @var{display} is
1258 @table @option
1260 @item to=@var{L}
1262 With this option, QEMU will try next available VNC @var{display}s, until the
1264 available, e.g. port 5900+@var{display} is already used by another
1265 application. By default, to=0.
1267 @item @var{host}:@var{d}
1269 TCP connections will only be allowed from @var{host} on display @var{d}.
1270 By convention the TCP port is 5900+@var{d}. Optionally, @var{host} can
1271 be omitted in which case the server will accept connections from any host.
1273 @item unix:@var{path}
1275 Connections will be allowed over UNIX domain sockets where @var{path} is the
1276 location of a unix socket to listen for connections on.
1278 @item none
1280 VNC is initialized but not started. The monitor @code{change} command
1281 can be used to later start the VNC server.
1283 @end table
1285 Following the @var{display} value there may be one or more @var{option} flags
1286 separated by commas. Valid options are
1288 @table @option
1290 @item reverse
1292 Connect to a listening VNC client via a ``reverse'' connection. The
1293 client is specified by the @var{display}. For reverse network
1294 connections (@var{host}:@var{d},@code{reverse}), the @var{d} argument
1295 is a TCP port number, not a display number.
1297 @item websocket
1299 Opens an additional TCP listening port dedicated to VNC Websocket connections.
1300 By definition the Websocket port is 5700+@var{display}. If @var{host} is
1301 specified connections will only be allowed from this host.
1302 As an alternative the Websocket port could be specified by using
1303 @code{websocket}=@var{port}.
1304 If no TLS credentials are provided, the websocket connection runs in
1305 unencrypted mode. If TLS credentials are provided, the websocket connection
1306 requires encrypted client connections.
1308 @item password
1310 Require that password based authentication is used for client connections.
1312 The password must be set separately using the @code{set_password} command in
1313 the @ref{pcsys_monitor}. The syntax to change your password is:
1314 @code{set_password <protocol> <password>} where <protocol> could be either
1317 If you would like to change <protocol> password expiration, you should use
1318 @code{expire_password <protocol> <expiration-time>} where expiration time could
1319 be one of the following options: now, never, +seconds or UNIX time of
1320 expiration, e.g. +60 to make password expire in 60 seconds, or 1335196800
1322 date and time).
1325 allow <protocol> password to expire immediately or never expire.
1327 @item tls-creds=@var{ID}
1329 Provides the ID of a set of TLS credentials to use to secure the
1330 VNC server. They will apply to both the normal VNC server socket
1331 and the websocket socket (if enabled). Setting TLS credentials
1332 will cause the VNC server socket to enable the VeNCrypt auth
1333 mechanism. The credentials should have been previously created
1334 using the @option{-object tls-creds} argument.
1336 The @option{tls-creds} parameter obsoletes the @option{tls},
1337 @option{x509}, and @option{x509verify} options, and as such
1338 it is not permitted to set both new and old type options at
1339 the same time.
1341 @item tls
1343 Require that client use TLS when communicating with the VNC server. This
1344 uses anonymous TLS credentials so is susceptible to a man-in-the-middle
1345 attack. It is recommended that this option be combined with either the
1346 @option{x509} or @option{x509verify} options.
1348 This option is now deprecated in favor of using the @option{tls-creds}
1349 argument.
1351 @item x509=@var{/path/to/certificate/dir}
1353 Valid if @option{tls} is specified. Require that x509 credentials are used
1354 for negotiating the TLS session. The server will send its x509 certificate
1355 to the client. It is recommended that a password be set on the VNC server
1356 to provide authentication of the client when this is used. The path following
1357 this option specifies where the x509 certificates are to be loaded from.
1358 See the @ref{vnc_security} section for details on generating certificates.
1360 This option is now deprecated in favour of using the @option{tls-creds}
1361 argument.
1363 @item x509verify=@var{/path/to/certificate/dir}
1365 Valid if @option{tls} is specified. Require that x509 credentials are used
1366 for negotiating the TLS session. The server will send its x509 certificate
1367 to the client, and request that the client send its own x509 certificate.
1368 The server will validate the client's certificate against the CA certificate,
1369 and reject clients when validation fails. If the certificate authority is
1370 trusted, this is a sufficient authentication mechanism. You may still wish
1371 to set a password on the VNC server as a second authentication layer. The
1372 path following this option specifies where the x509 certificates are to
1373 be loaded from. See the @ref{vnc_security} section for details on generating
1374 certificates.
1376 This option is now deprecated in favour of using the @option{tls-creds}
1377 argument.
1379 @item sasl
1381 Require that the client use SASL to authenticate with the VNC server.
1382 The exact choice of authentication method used is controlled from the
1383 system / user's SASL configuration file for the 'qemu' service. This
1384 is typically found in /etc/sasl2/qemu.conf. If running QEMU as an
1385 unprivileged user, an environment variable SASL_CONF_PATH can be used
1386 to make it search alternate locations for the service config.
1387 While some SASL auth methods can also provide data encryption (eg GSSAPI),
1388 it is recommended that SASL always be combined with the 'tls' and
1389 'x509' settings to enable use of SSL and server certificates. This
1390 ensures a data encryption preventing compromise of authentication
1391 credentials. See the @ref{vnc_security} section for details on using
1392 SASL authentication.
1394 @item acl
1396 Turn on access control lists for checking of the x509 client certificate
1397 and SASL party. For x509 certs, the ACL check is made against the
1398 certificate's distinguished name. This is something that looks like
1399 @code{C=GB,O=ACME,L=Boston,CN=bob}. For SASL party, the ACL check is
1400 made against the username, which depending on the SASL plugin, may
1401 include a realm component, eg @code{bob} or @code{bob@@EXAMPLE.COM}.
1402 When the @option{acl} flag is set, the initial access list will be
1403 empty, with a @code{deny} policy. Thus no one will be allowed to
1404 use the VNC server until the ACLs have been loaded. This can be
1405 achieved using the @code{acl} monitor command.
1407 @item lossy
1409 Enable lossy compression methods (gradient, JPEG, ...). If this
1410 option is set, VNC client may receive lossy framebuffer updates
1411 depending on its encoding settings. Enabling this option can save
1412 a lot of bandwidth at the expense of quality.
1414 @item non-adaptive
1416 Disable adaptive encodings. Adaptive encodings are enabled by default.
1417 An adaptive encoding will try to detect frequently updated screen regions,
1418 and send updates in these regions using a lossy encoding (like JPEG).
1419 This can be really helpful to save bandwidth when playing videos. Disabling
1420 adaptive encodings restores the original static behavior of encodings
1421 like Tight.
1423 @item share=[allow-exclusive|force-shared|ignore]
1425 Set display sharing policy. 'allow-exclusive' allows clients to ask
1426 for exclusive access. As suggested by the rfb spec this is
1427 implemented by dropping other connections. Connecting multiple
1428 clients in parallel requires all clients asking for a shared session
1429 (vncviewer: -shared switch). This is the default. 'force-shared'
1430 disables exclusive client access. Useful for shared desktop sessions,
1431 where you don't want someone forgetting specify -shared disconnect
1432 everybody else. 'ignore' completely ignores the shared flag and
1433 allows everybody connect unconditionally. Doesn't conform to the rfb
1434 spec but is traditional QEMU behavior.
1436 @item key-delay-ms
1438 Set keyboard delay, for key down and key up events, in milliseconds.
1439 Default is 1. Keyboards are low-bandwidth devices, so this slowdown
1440 can help the device and guest to keep up and not lose events in case
1441 events are arriving in bulk. Possible causes for the latter are flaky
1442 network connections, or scripts for automated testing.
1444 @end table
1445 ETEXI
1447 STEXI
1448 @end table
1449 ETEXI
1450 ARCHHEADING(, QEMU_ARCH_I386)
1452 ARCHHEADING(i386 target only:, QEMU_ARCH_I386)
1453 STEXI
1454 @table @option
1455 ETEXI
1459 QEMU_ARCH_I386)
1460 STEXI
1461 @item -win2k-hack
1462 @findex -win2k-hack
1463 Use it when installing Windows 2000 to avoid a disk full bug. After
1464 Windows 2000 is installed, you no longer need this option (this option
1465 slows down the IDE transfers).
1466 ETEXI
1468 HXCOMM Deprecated by -rtc
1473 QEMU_ARCH_I386)
1474 STEXI
1475 @item -no-fd-bootchk
1476 @findex -no-fd-bootchk
1477 Disable boot signature checking for floppy disks in BIOS. May
1478 be needed to boot from old floppy disks.
1479 ETEXI
1483 STEXI
1484 @item -no-acpi
1485 @findex -no-acpi
1486 Disable ACPI (Advanced Configuration and Power Interface) support. Use
1487 it if your guest OS complains about ACPI problems (PC target machine
1488 only).
1489 ETEXI
1493 STEXI
1494 @item -no-hpet
1495 @findex -no-hpet
1496 Disable HPET support.
1497 ETEXI
1500 "-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"
1502 STEXI
1503 @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}]...]
1504 @findex -acpitable
1505 Add ACPI table with specified header fields and context from specified files.
1506 For file=, take whole ACPI table from the specified files, including all
1507 ACPI headers (possible overridden by other options).
1508 For data=, only data
1509 portion of the table is used, all header information is specified in the
1510 command line.
1511 If a SLIC table is supplied to QEMU, then the SLIC's oem_id and oem_table_id
1512 fields will override the same in the RSDT and the FADT (a.k.a. FACP), in order
1513 to ensure the field matches required by the Microsoft SLIC spec and the ACPI
1514 spec.
1515 ETEXI
1538 QEMU_ARCH_I386 | QEMU_ARCH_ARM)
1539 STEXI
1540 @item -smbios file=@var{binary}
1541 @findex -smbios
1542 Load SMBIOS entry from binary file.
1544 @item -smbios type=0[,vendor=@var{str}][,version=@var{str}][,date=@var{str}][,release=@var{%d.%d}][,uefi=on|off]
1545 Specify SMBIOS type 0 fields
1547 @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}]
1548 Specify SMBIOS type 1 fields
1550 @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}]
1551 Specify SMBIOS type 2 fields
1553 @item -smbios type=3[,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,sku=@var{str}]
1554 Specify SMBIOS type 3 fields
1556 @item -smbios type=4[,sock_pfx=@var{str}][,manufacturer=@var{str}][,version=@var{str}][,serial=@var{str}][,asset=@var{str}][,part=@var{str}]
1557 Specify SMBIOS type 4 fields
1559 @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}]
1560 Specify SMBIOS type 17 fields
1561 ETEXI
1563 STEXI
1564 @end table
1565 ETEXI
1566 DEFHEADING()
1568 DEFHEADING(Network options:)
1569 STEXI
1570 @table @option
1571 ETEXI
1573 HXCOMM Legacy slirp options (now moved to -net user):
1574 #ifdef CONFIG_SLIRP
1578 #ifndef _WIN32
1580 #endif
1581 #endif
1584 #ifdef CONFIG_SLIRP
1590 #ifndef _WIN32
1592 #endif
1595 #endif
1596 #ifdef _WIN32
1599 #else
1630 #endif
1631 #ifdef __linux__
1657 #endif
1667 #ifdef CONFIG_VDE
1673 #endif
1674 #ifdef CONFIG_NETMAP
1679 #endif
1693 #ifdef CONFIG_SLIRP
1695 #endif
1698 #ifdef CONFIG_VDE
1700 #endif
1701 #ifdef CONFIG_NETMAP
1703 #endif
1707 STEXI
1708 @item -net nic[,vlan=@var{n}][,macaddr=@var{mac}][,model=@var{type}] [,name=@var{name}][,addr=@var{addr}][,vectors=@var{v}]
1709 @findex -net
1710 Create a new Network Interface Card and connect it to VLAN @var{n} (@var{n}
1711 = 0 is the default). The NIC is an e1000 by default on the PC
1712 target. Optionally, the MAC address can be changed to @var{mac}, the
1713 device address set to @var{addr} (PCI cards only),
1714 and a @var{name} can be assigned for use in monitor commands.
1715 Optionally, for PCI cards, you can specify the number @var{v} of MSI-X vectors
1716 that the card should have; this option currently only affects virtio cards; set
1717 @var{v} = 0 to disable MSI-X. If no @option{-net} option is specified, a single
1718 NIC is created. QEMU can emulate several different models of network card.
1719 Valid values for @var{type} are
1720 @code{virtio}, @code{i82551}, @code{i82557b}, @code{i82559er},
1721 @code{ne2k_pci}, @code{ne2k_isa}, @code{pcnet}, @code{rtl8139},
1722 @code{e1000}, @code{smc91c111}, @code{lance} and @code{mcf_fec}.
1723 Not all devices are supported on all targets. Use @code{-net nic,model=help}
1724 for a list of available devices for your target.
1726 @item -netdev user,id=@var{id}[,@var{option}][,@var{option}][,...]
1727 @findex -netdev
1728 @item -net user[,@var{option}][,@var{option}][,...]
1729 Use the user mode network stack which requires no administrator
1730 privilege to run. Valid options are:
1732 @table @option
1733 @item vlan=@var{n}
1734 Connect user mode stack to VLAN @var{n} (@var{n} = 0 is the default).
1736 @item id=@var{id}
1737 @itemx name=@var{name}
1738 Assign symbolic name for use in monitor commands.
1740 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must
1741 be enabled. If neither is specified both protocols are enabled.
1743 @item net=@var{addr}[/@var{mask}]
1744 Set IP network address the guest will see. Optionally specify the netmask,
1745 either in the form a.b.c.d or as number of valid top-most bits. Default is
1746 10.0.2.0/24.
1748 @item host=@var{addr}
1749 Specify the guest-visible address of the host. Default is the 2nd IP in the
1750 guest network, i.e. x.x.x.2.
1752 @item ipv6-net=@var{addr}[/@var{int}]
1753 Set IPv6 network address the guest will see (default is fec0::/64). The
1754 network prefix is given in the usual hexadecimal IPv6 address
1755 notation. The prefix size is optional, and is given as the number of
1756 valid top-most bits (default is 64).
1758 @item ipv6-host=@var{addr}
1759 Specify the guest-visible IPv6 address of the host. Default is the 2nd IPv6 in
1760 the guest network, i.e. xxxx::2.
1762 @item restrict=on|off
1763 If this option is enabled, the guest will be isolated, i.e. it will not be
1764 able to contact the host and no guest IP packets will be routed over the host
1765 to the outside. This option does not affect any explicitly set forwarding rules.
1767 @item hostname=@var{name}
1768 Specifies the client hostname reported by the built-in DHCP server.
1770 @item dhcpstart=@var{addr}
1771 Specify the first of the 16 IPs the built-in DHCP server can assign. Default
1772 is the 15th to 31st IP in the guest network, i.e. x.x.x.15 to x.x.x.31.
1774 @item dns=@var{addr}
1775 Specify the guest-visible address of the virtual nameserver. The address must
1776 be different from the host address. Default is the 3rd IP in the guest network,
1777 i.e. x.x.x.3.
1779 @item ipv6-dns=@var{addr}
1780 Specify the guest-visible address of the IPv6 virtual nameserver. The address
1781 must be different from the host address. Default is the 3rd IP in the guest
1782 network, i.e. xxxx::3.
1784 @item dnssearch=@var{domain}
1785 Provides an entry for the domain-search list sent by the built-in
1786 DHCP server. More than one domain suffix can be transmitted by specifying
1787 this option multiple times. If supported, this will cause the guest to
1788 automatically try to append the given domain suffix(es) in case a domain name
1789 can not be resolved.
1791 Example:
1792 @example
1793 qemu -net user,dnssearch=mgmt.example.org,dnssearch=example.org [...]
1794 @end example
1796 @item tftp=@var{dir}
1797 When using the user mode network stack, activate a built-in TFTP
1798 server. The files in @var{dir} will be exposed as the root of a TFTP server.
1799 The TFTP client on the guest must be configured in binary mode (use the command
1800 @code{bin} of the Unix TFTP client).
1802 @item bootfile=@var{file}
1803 When using the user mode network stack, broadcast @var{file} as the BOOTP
1804 filename. In conjunction with @option{tftp}, this can be used to network boot
1805 a guest from a local directory.
1807 Example (using pxelinux):
1808 @example
1809 qemu-system-i386 -hda linux.img -boot n -net user,tftp=/path/to/tftp/files,bootfile=/pxelinux.0
1810 @end example
1812 @item smb=@var{dir}[,smbserver=@var{addr}]
1813 When using the user mode network stack, activate a built-in SMB
1814 server so that Windows OSes can access to the host files in @file{@var{dir}}
1815 transparently. The IP address of the SMB server can be set to @var{addr}. By
1816 default the 4th IP in the guest network is used, i.e. x.x.x.4.
1818 In the guest Windows OS, the line:
1819 @example
1820 10.0.2.4 smbserver
1821 @end example
1822 must be added in the file @file{C:\WINDOWS\LMHOSTS} (for windows 9x/Me)
1823 or @file{C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS} (Windows NT/2000).
1827 Note that a SAMBA server must be installed on the host OS.
1828 QEMU was tested successfully with smbd versions from Red Hat 9,
1829 Fedora Core 3 and OpenSUSE 11.x.
1831 @item hostfwd=[tcp|udp]:[@var{hostaddr}]:@var{hostport}-[@var{guestaddr}]:@var{guestport}
1832 Redirect incoming TCP or UDP connections to the host port @var{hostport} to
1833 the guest IP address @var{guestaddr} on guest port @var{guestport}. If
1834 @var{guestaddr} is not specified, its value is x.x.x.15 (default first address
1835 given by the built-in DHCP server). By specifying @var{hostaddr}, the rule can
1836 be bound to a specific host interface. If no connection type is set, TCP is
1837 used. This option can be given multiple times.
1839 For example, to redirect host X11 connection from screen 1 to guest
1840 screen 0, use the following:
1842 @example
1843 # on the host
1844 qemu-system-i386 -net user,hostfwd=tcp:127.0.0.1:6001-:6000 [...]
1845 # this host xterm should open in the guest X11 server
1846 xterm -display :1
1847 @end example
1849 To redirect telnet connections from host port 5555 to telnet port on
1850 the guest, use the following:
1852 @example
1853 # on the host
1854 qemu-system-i386 -net user,hostfwd=tcp::5555-:23 [...]
1855 telnet localhost 5555
1856 @end example
1858 Then when you use on the host @code{telnet localhost 5555}, you
1859 connect to the guest telnet server.
1861 @item guestfwd=[tcp]:@var{server}:@var{port}-@var{dev}
1862 @itemx guestfwd=[tcp]:@var{server}:@var{port}-@var{cmd:command}
1863 Forward guest TCP connections to the IP address @var{server} on port @var{port}
1864 to the character device @var{dev} or to a program executed by @var{cmd:command}
1865 which gets spawned for each connection. This option can be given multiple times.
1867 You can either use a chardev directly and have that one used throughout QEMU's
1868 lifetime, like in the following example:
1870 @example
1871 # open 10.10.1.1:4321 on bootup, connect 10.0.2.100:1234 to it whenever
1872 # the guest accesses it
1873 qemu -net user,guestfwd=tcp:10.0.2.100:1234-tcp:10.10.1.1:4321 [...]
1874 @end example
1876 Or you can execute a command on every TCP connection established by the guest,
1877 so that QEMU behaves similar to an inetd process for that virtual server:
1879 @example
1881 # and connect the TCP stream to its stdin/stdout
1882 qemu -net 'user,guestfwd=tcp:10.0.2.100:1234-cmd:netcat 10.10.1.1 4321'
1883 @end example
1885 @end table
1887 Note: Legacy stand-alone options -tftp, -bootp, -smb and -redir are still
1888 processed and applied to -net user. Mixing them with the new configuration
1889 syntax gives undefined results. Their use for new applications is discouraged
1890 as they will be removed from future versions.
1892 @item -netdev tap,id=@var{id}[,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}]
1893 @itemx -net tap[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,ifname=@var{name}][,script=@var{file}][,downscript=@var{dfile}][,br=@var{bridge}][,helper=@var{helper}]
1894 Connect the host TAP network interface @var{name} to VLAN @var{n}.
1896 Use the network script @var{file} to configure it and the network script
1897 @var{dfile} to deconfigure it. If @var{name} is not provided, the OS
1898 automatically provides one. The default network configure script is
1899 @file{/etc/qemu-ifup} and the default network deconfigure script is
1900 @file{/etc/qemu-ifdown}. Use @option{script=no} or @option{downscript=no}
1901 to disable script execution.
1903 If running QEMU as an unprivileged user, use the network helper
1904 @var{helper} to configure the TAP interface and attach it to the bridge.
1905 The default network helper executable is @file{/path/to/qemu-bridge-helper}
1906 and the default bridge device is @file{br0}.
1908 @option{fd}=@var{h} can be used to specify the handle of an already
1909 opened host TAP interface.
1911 Examples:
1913 @example
1914 #launch a QEMU instance with the default network script
1915 qemu-system-i386 linux.img -net nic -net tap
1916 @end example
1918 @example
1919 #launch a QEMU instance with two NICs, each one connected
1920 #to a TAP device
1921 qemu-system-i386 linux.img \
1922 -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
1923 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
1924 @end example
1926 @example
1927 #launch a QEMU instance with the default network helper to
1928 #connect a TAP device to bridge br0
1929 qemu-system-i386 linux.img \
1931 @end example
1933 @item -netdev bridge,id=@var{id}[,br=@var{bridge}][,helper=@var{helper}]
1934 @itemx -net bridge[,vlan=@var{n}][,name=@var{name}][,br=@var{bridge}][,helper=@var{helper}]
1935 Connect a host TAP network interface to a host bridge device.
1937 Use the network helper @var{helper} to configure the TAP interface and
1938 attach it to the bridge. The default network helper executable is
1939 @file{/path/to/qemu-bridge-helper} and the default bridge
1940 device is @file{br0}.
1942 Examples:
1944 @example
1945 #launch a QEMU instance with the default network helper to
1946 #connect a TAP device to bridge br0
1947 qemu-system-i386 linux.img -net bridge -net nic,model=virtio
1948 @end example
1950 @example
1951 #launch a QEMU instance with the default network helper to
1952 #connect a TAP device to bridge qemubr0
1953 qemu-system-i386 linux.img -net bridge,br=qemubr0 -net nic,model=virtio
1954 @end example
1956 @item -netdev socket,id=@var{id}[,fd=@var{h}][,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1957 @itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}] [,listen=[@var{host}]:@var{port}][,connect=@var{host}:@var{port}]
1959 Connect the VLAN @var{n} to a remote VLAN in another QEMU virtual
1960 machine using a TCP socket connection. If @option{listen} is
1961 specified, QEMU waits for incoming connections on @var{port}
1962 (@var{host} is optional). @option{connect} is used to connect to
1963 another QEMU instance using the @option{listen} option. @option{fd}=@var{h}
1964 specifies an already opened TCP socket.
1966 Example:
1967 @example
1968 # launch a first QEMU instance
1969 qemu-system-i386 linux.img \
1970 -net nic,macaddr=52:54:00:12:34:56 \
1971 -net socket,listen=:1234
1972 # connect the VLAN 0 of this instance to the VLAN 0
1973 # of the first instance
1974 qemu-system-i386 linux.img \
1975 -net nic,macaddr=52:54:00:12:34:57 \
1976 -net socket,connect=127.0.0.1:1234
1977 @end example
1979 @item -netdev socket,id=@var{id}[,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1980 @itemx -net socket[,vlan=@var{n}][,name=@var{name}][,fd=@var{h}][,mcast=@var{maddr}:@var{port}[,localaddr=@var{addr}]]
1982 Create a VLAN @var{n} shared with another QEMU virtual
1983 machines using a UDP multicast socket, effectively making a bus for
1984 every QEMU with same multicast address @var{maddr} and @var{port}.
1985 NOTES:
1986 @enumerate
1987 @item
1988 Several QEMU can be running on different hosts and share same bus (assuming
1989 correct multicast setup for these hosts).
1990 @item
1991 mcast support is compatible with User Mode Linux (argument @option{eth@var{N}=mcast}), see
1992 @url{http://user-mode-linux.sf.net}.
1993 @item
1994 Use @option{fd=h} to specify an already opened UDP multicast socket.
1995 @end enumerate
1997 Example:
1998 @example
1999 # launch one QEMU instance
2000 qemu-system-i386 linux.img \
2001 -net nic,macaddr=52:54:00:12:34:56 \
2002 -net socket,mcast=230.0.0.1:1234
2004 qemu-system-i386 linux.img \
2005 -net nic,macaddr=52:54:00:12:34:57 \
2006 -net socket,mcast=230.0.0.1:1234
2008 qemu-system-i386 linux.img \
2009 -net nic,macaddr=52:54:00:12:34:58 \
2010 -net socket,mcast=230.0.0.1:1234
2011 @end example
2013 Example (User Mode Linux compat.):
2014 @example
2015 # launch QEMU instance (note mcast address selected
2016 # is UML's default)
2017 qemu-system-i386 linux.img \
2018 -net nic,macaddr=52:54:00:12:34:56 \
2019 -net socket,mcast=239.192.168.1:1102
2020 # launch UML
2021 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
2022 @end example
2024 Example (send packets from host's 1.2.3.4):
2025 @example
2026 qemu-system-i386 linux.img \
2027 -net nic,macaddr=52:54:00:12:34:56 \
2028 -net socket,mcast=239.192.168.1:1102,localaddr=1.2.3.4
2029 @end example
2031 @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}]
2032 @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}]
2033 Connect VLAN @var{n} to L2TPv3 pseudowire. L2TPv3 (RFC3391) is a popular
2034 protocol to transport Ethernet (and other Layer 2) data frames between
2035 two systems. It is present in routers, firewalls and the Linux kernel
2036 (from version 3.3 onwards).
2038 This transport allows a VM to communicate to another VM, router or firewall directly.
2040 @item src=@var{srcaddr}
2041 source address (mandatory)
2042 @item dst=@var{dstaddr}
2043 destination address (mandatory)
2044 @item udp
2045 select udp encapsulation (default is ip).
2046 @item srcport=@var{srcport}
2047 source udp port.
2048 @item dstport=@var{dstport}
2049 destination udp port.
2050 @item ipv6
2051 force v6, otherwise defaults to v4.
2052 @item rxcookie=@var{rxcookie}
2053 @itemx txcookie=@var{txcookie}
2054 Cookies are a weak form of security in the l2tpv3 specification.
2055 Their function is mostly to prevent misconfiguration. By default they are 32
2056 bit.
2057 @item cookie64
2058 Set cookie size to 64 bit instead of the default 32
2059 @item counter=off
2060 Force a 'cut-down' L2TPv3 with no counter as in
2061 draft-mkonstan-l2tpext-keyed-ipv6-tunnel-00
2062 @item pincounter=on
2063 Work around broken counter handling in peer. This may also help on
2064 networks which have packet reorder.
2065 @item offset=@var{offset}
2066 Add an extra offset between header and data
2068 For example, to attach a VM running on host 4.3.2.1 via L2TPv3 to the bridge br-lan
2069 on the remote Linux host 1.2.3.4:
2070 @example
2071 # Setup tunnel on linux host using raw ip as encapsulation
2072 # on 1.2.3.4
2073 ip l2tp add tunnel remote 4.3.2.1 local 1.2.3.4 tunnel_id 1 peer_tunnel_id 1 \
2074 encap udp udp_sport 16384 udp_dport 16384
2075 ip l2tp add session tunnel_id 1 name vmtunnel0 session_id \
2076 0xFFFFFFFF peer_session_id 0xFFFFFFFF
2077 ifconfig vmtunnel0 mtu 1500
2078 ifconfig vmtunnel0 up
2079 brctl addif br-lan vmtunnel0
2082 # on 4.3.2.1
2083 # launch QEMU instance - if your network has reorder or is very lossy add ,pincounter
2085 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
2088 @end example
2090 @item -netdev vde,id=@var{id}[,sock=@var{socketpath}][,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2091 @itemx -net vde[,vlan=@var{n}][,name=@var{name}][,sock=@var{socketpath}] [,port=@var{n}][,group=@var{groupname}][,mode=@var{octalmode}]
2092 Connect VLAN @var{n} to PORT @var{n} of a vde switch running on host and
2093 listening for incoming connections on @var{socketpath}. Use GROUP @var{groupname}
2094 and MODE @var{octalmode} to change default ownership and permissions for
2095 communication port. This option is only available if QEMU has been compiled
2096 with vde support enabled.
2098 Example:
2099 @example
2100 # launch vde switch
2101 vde_switch -F -sock /tmp/myswitch
2102 # launch QEMU instance
2103 qemu-system-i386 linux.img -net nic -net vde,sock=/tmp/myswitch
2104 @end example
2106 @item -netdev hubport,id=@var{id},hubid=@var{hubid}
2111 netdev. @code{-net} and @code{-device} with parameter @option{vlan} create the
2112 required hub automatically.
2114 @item -netdev vhost-user,chardev=@var{id}[,vhostforce=on|off][,queues=n]
2116 Establish a vhost-user netdev, backed by a chardev @var{id}. The chardev should
2117 be a unix domain socket backed one. The vhost-user uses a specifically defined
2118 protocol to pass vhost ioctl replacement messages to an application on the other
2119 end of the socket. On non-MSIX guests, the feature can be forced with
2120 @var{vhostforce}. Use 'queues=@var{n}' to specify the number of queues to
2121 be created for multiqueue vhost-user.
2123 Example:
2124 @example
2125 qemu -m 512 -object memory-backend-file,id=mem,size=512M,mem-path=/hugetlbfs,share=on \
2126 -numa node,memdev=mem \
2127 -chardev socket,path=/path/to/socket \
2128 -netdev type=vhost-user,id=net0,chardev=chr0 \
2129 -device virtio-net-pci,netdev=net0
2130 @end example
2132 @item -net dump[,vlan=@var{n}][,file=@var{file}][,len=@var{len}]
2133 Dump network traffic on VLAN @var{n} to file @var{file} (@file{qemu-vlan0.pcap} by default).
2134 At most @var{len} bytes (64k by default) per packet are stored. The file format is
2135 libpcap, so it can be analyzed with tools such as tcpdump or Wireshark.
2136 Note: For devices created with '-netdev', use '-object filter-dump,...' instead.
2138 @item -net none
2139 Indicate that no network devices should be configured. It is used to
2140 override the default configuration (@option{-net nic -net user}) which
2141 is activated if no @option{-net} options are provided.
2142 ETEXI
2144 STEXI
2145 @end table
2146 ETEXI
2147 DEFHEADING()
2149 DEFHEADING(Character device options:)
2150 STEXI
2152 The general form of a character device option is:
2153 @table @option
2154 ETEXI
2159 "-chardev socket,id=id[,host=host],port=port[,to=to][,ipv4][,ipv6][,nodelay][,reconnect=seconds]\n"
2173 #ifdef _WIN32
2176 #else
2179 #endif
2180 #ifdef CONFIG_BRLAPI
2182 #endif
2183 #if defined(__linux__) || defined(__sun__) || defined(__FreeBSD__) \
2184 || defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
2187 #endif
2188 #if defined(__linux__) || defined(__FreeBSD__) || defined(__DragonFly__)
2191 #endif
2192 #if defined(CONFIG_SPICE)
2195 #endif
2196 , QEMU_ARCH_ALL
2197 )
2199 STEXI
2200 @item -chardev @var{backend} ,id=@var{id} [,mux=on|off] [,@var{options}]
2201 @findex -chardev
2202 Backend is one of:
2203 @option{null},
2204 @option{socket},
2205 @option{udp},
2206 @option{msmouse},
2207 @option{vc},
2208 @option{ringbuf},
2209 @option{file},
2210 @option{pipe},
2211 @option{console},
2212 @option{serial},
2213 @option{pty},
2214 @option{stdio},
2215 @option{braille},
2216 @option{tty},
2217 @option{parallel},
2218 @option{parport},
2219 @option{spicevmc}.
2220 @option{spiceport}.
2221 The specific backend will determine the applicable options.
2225 All devices must have an id, which can be any string up to 127 characters long.
2226 It is used to uniquely identify this device in other command line directives.
2228 A character device may be used in multiplexing mode by multiple front-ends.
2229 Specify @option{mux=on} to enable this mode.
2232 If you create a chardev with @option{id=myid} and @option{mux=on}, QEMU will
2233 create a multiplexer with your specified ID, and you can then configure multiple
2234 front ends to use that chardev ID for their input/output. Up to four different
2235 front ends can be connected to a single multiplexed chardev. (Without
2236 multiplexing enabled, a chardev can only be used by a single front end.)
2237 For instance you could use this to allow a single stdio chardev to be used by
2238 two serial ports and the QEMU monitor:
2240 @example
2241 -chardev stdio,mux=on,id=char0 \
2242 -mon chardev=char0,mode=readline \
2243 -serial chardev:char0 \
2244 -serial chardev:char0
2245 @end example
2247 You can have more than one multiplexer in a system configuration; for instance
2248 you could have a TCP port multiplexed between UART 0 and UART 1, and stdio
2249 multiplexed between the QEMU monitor and a parallel port:
2251 @example
2252 -chardev stdio,mux=on,id=char0 \
2253 -mon chardev=char0,mode=readline \
2254 -parallel chardev:char0 \
2255 -chardev tcp,...,mux=on,id=char1 \
2256 -serial chardev:char1 \
2257 -serial chardev:char1
2258 @end example
2260 When you're using a multiplexed character device, some escape sequences are
2261 interpreted in the input. @xref{mux_keys, Keys in the character backend
2262 multiplexer}.
2264 Note that some other command line options may implicitly create multiplexed
2265 character backends; for instance @option{-serial mon:stdio} creates a
2266 multiplexed stdio backend connected to the serial port and the QEMU monitor,
2267 and @option{-nographic} also multiplexes the console and the monitor to
2268 stdio.
2270 There is currently no support for multiplexing in the other direction
2271 (where a single QEMU front end takes input and output from multiple chardevs).
2273 Every backend supports the @option{logfile} option, which supplies the path
2274 to a file to record all data transmitted via the backend. The @option{logappend}
2275 option controls whether the log file will be truncated or appended to when
2276 opened.
2278 Further options to each backend are described below.
2280 @item -chardev null ,id=@var{id}
2281 A void device. This device will not emit any data, and will drop any data it
2282 receives. The null backend does not take any options.
2284 @item -chardev socket ,id=@var{id} [@var{TCP options} or @var{unix options}] [,server] [,nowait] [,telnet] [,reconnect=@var{seconds}] [,tls-creds=@var{id}]
2286 Create a two-way stream socket, which can be either a TCP or a unix socket. A
2287 unix socket will be created if @option{path} is specified. Behaviour is
2288 undefined if TCP options are specified for a unix socket.
2290 @option{server} specifies that the socket shall be a listening socket.
2292 @option{nowait} specifies that QEMU should not block waiting for a client to
2293 connect to a listening socket.
2295 @option{telnet} specifies that traffic on the socket should interpret telnet
2296 escape sequences.
2298 @option{reconnect} sets the timeout for reconnecting on non-server sockets when
2299 the remote end goes away. qemu will delay this many seconds and then attempt
2300 to reconnect. Zero disables reconnecting, and is the default.
2302 @option{tls-creds} requests enablement of the TLS protocol for encryption,
2303 and specifies the id of the TLS credentials to use for the handshake. The
2304 credentials must be previously created with the @option{-object tls-creds}
2305 argument.
2307 TCP and unix socket options are given below:
2309 @table @option
2311 @item TCP options: port=@var{port} [,host=@var{host}] [,to=@var{to}] [,ipv4] [,ipv6] [,nodelay]
2313 @option{host} for a listening socket specifies the local address to be bound.
2314 For a connecting socket species the remote host to connect to. @option{host} is
2315 optional for listening sockets. If not specified it defaults to @code{0.0.0.0}.
2317 @option{port} for a listening socket specifies the local port to be bound. For a
2318 connecting socket specifies the port on the remote host to connect to.
2319 @option{port} can be given as either a port number or a service name.
2320 @option{port} is required.
2322 @option{to} is only relevant to listening sockets. If it is specified, and
2323 @option{port} cannot be bound, QEMU will attempt to bind to subsequent ports up
2324 to and including @option{to} until it succeeds. @option{to} must be specified
2325 as a port number.
2327 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2328 If neither is specified the socket may use either protocol.
2330 @option{nodelay} disables the Nagle algorithm.
2332 @item unix options: path=@var{path}
2334 @option{path} specifies the local path of the unix socket. @option{path} is
2335 required.
2337 @end table
2339 @item -chardev udp ,id=@var{id} [,host=@var{host}] ,port=@var{port} [,localaddr=@var{localaddr}] [,localport=@var{localport}] [,ipv4] [,ipv6]
2341 Sends all traffic from the guest to a remote host over UDP.
2343 @option{host} specifies the remote host to connect to. If not specified it
2344 defaults to @code{localhost}.
2346 @option{port} specifies the port on the remote host to connect to. @option{port}
2347 is required.
2349 @option{localaddr} specifies the local address to bind to. If not specified it
2350 defaults to @code{0.0.0.0}.
2352 @option{localport} specifies the local port to bind to. If not specified any
2353 available local port will be used.
2355 @option{ipv4} and @option{ipv6} specify that either IPv4 or IPv6 must be used.
2356 If neither is specified the device may use either protocol.
2358 @item -chardev msmouse ,id=@var{id}
2360 Forward QEMU's emulated msmouse events to the guest. @option{msmouse} does not
2361 take any options.
2363 @item -chardev vc ,id=@var{id} [[,width=@var{width}] [,height=@var{height}]] [[,cols=@var{cols}] [,rows=@var{rows}]]
2365 Connect to a QEMU text console. @option{vc} may optionally be given a specific
2366 size.
2368 @option{width} and @option{height} specify the width and height respectively of
2369 the console, in pixels.
2371 @option{cols} and @option{rows} specify that the console be sized to fit a text
2372 console with the given dimensions.
2374 @item -chardev ringbuf ,id=@var{id} [,size=@var{size}]
2376 Create a ring buffer with fixed size @option{size}.
2377 @var{size} must be a power of two and defaults to @code{64K}.
2379 @item -chardev file ,id=@var{id} ,path=@var{path}
2381 Log all traffic received from the guest to a file.
2383 @option{path} specifies the path of the file to be opened. This file will be
2384 created if it does not already exist, and overwritten if it does. @option{path}
2385 is required.
2387 @item -chardev pipe ,id=@var{id} ,path=@var{path}
2389 Create a two-way connection to the guest. The behaviour differs slightly between
2390 Windows hosts and other hosts:
2392 On Windows, a single duplex pipe will be created at
2395 On other hosts, 2 pipes will be created called @file{@option{path}.in} and
2396 @file{@option{path}.out}. Data written to @file{@option{path}.in} will be
2397 received by the guest. Data written by the guest can be read from
2398 @file{@option{path}.out}. QEMU will not create these fifos, and requires them to
2399 be present.
2401 @option{path} forms part of the pipe path as described above. @option{path} is
2402 required.
2404 @item -chardev console ,id=@var{id}
2406 Send traffic from the guest to QEMU's standard output. @option{console} does not
2407 take any options.
2409 @option{console} is only available on Windows hosts.
2411 @item -chardev serial ,id=@var{id} ,path=@option{path}
2413 Send traffic from the guest to a serial device on the host.
2415 On Unix hosts serial will actually accept any tty device,
2416 not only serial lines.
2418 @option{path} specifies the name of the serial device to open.
2420 @item -chardev pty ,id=@var{id}
2422 Create a new pseudo-terminal on the host and connect to it. @option{pty} does
2423 not take any options.
2425 @option{pty} is not available on Windows hosts.
2427 @item -chardev stdio ,id=@var{id} [,signal=on|off]
2428 Connect to standard input and standard output of the QEMU process.
2430 @option{signal} controls if signals are enabled on the terminal, that includes
2431 exiting QEMU with the key sequence @key{Control-c}. This option is enabled by
2432 default, use @option{signal=off} to disable it.
2434 @option{stdio} is not available on Windows hosts.
2436 @item -chardev braille ,id=@var{id}
2438 Connect to a local BrlAPI server. @option{braille} does not take any options.
2440 @item -chardev tty ,id=@var{id} ,path=@var{path}
2442 @option{tty} is only available on Linux, Sun, FreeBSD, NetBSD, OpenBSD and
2443 DragonFlyBSD hosts. It is an alias for @option{serial}.
2445 @option{path} specifies the path to the tty. @option{path} is required.
2447 @item -chardev parallel ,id=@var{id} ,path=@var{path}
2448 @itemx -chardev parport ,id=@var{id} ,path=@var{path}
2450 @option{parallel} is only available on Linux, FreeBSD and DragonFlyBSD hosts.
2452 Connect to a local parallel port.
2454 @option{path} specifies the path to the parallel port device. @option{path} is
2455 required.
2457 @item -chardev spicevmc ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2459 @option{spicevmc} is only available when spice support is built in.
2461 @option{debug} debug level for spicevmc
2463 @option{name} name of spice channel to connect to
2465 Connect to a spice virtual machine channel, such as vdiport.
2467 @item -chardev spiceport ,id=@var{id} ,debug=@var{debug}, name=@var{name}
2469 @option{spiceport} is only available when spice support is built in.
2471 @option{debug} debug level for spicevmc
2473 @option{name} name of spice port to connect to
2475 Connect to a spice port, allowing a Spice client to handle the traffic
2476 identified by a name (preferably a fqdn).
2477 ETEXI
2479 STEXI
2480 @end table
2481 ETEXI
2482 DEFHEADING()
2484 DEFHEADING(Device URL Syntax:)
2485 STEXI
2487 In addition to using normal file images for the emulated storage devices,
2488 QEMU can also use networked resources such as iSCSI devices. These are
2489 specified using a special URL syntax.
2491 @table @option
2492 @item iSCSI
2493 iSCSI support allows QEMU to access iSCSI resources directly and use as
2494 images for the guest storage. Both disk and cdrom images are supported.
2496 Syntax for specifying iSCSI LUNs is
2497 ``iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>''
2499 By default qemu will use the iSCSI initiator-name
2500 'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from the command
2501 line or a configuration file.
2503 Since version Qemu 2.4 it is possible to specify a iSCSI request timeout to detect
2504 stalled requests and force a reestablishment of the session. The timeout
2505 is specified in seconds. The default is 0 which means no timeout. Libiscsi
2506 1.15.0 or greater is required for this feature.
2508 Example (without authentication):
2509 @example
2510 qemu-system-i386 -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \
2511 -cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \
2512 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2513 @end example
2515 Example (CHAP username/password via URL):
2516 @example
2517 qemu-system-i386 -drive file=iscsi://user%password@@192.0.2.1/iqn.2001-04.com.example/1
2518 @end example
2520 Example (CHAP username/password via environment variables):
2521 @example
2524 qemu-system-i386 -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
2525 @end example
2527 iSCSI support is an optional feature of QEMU and only available when
2528 compiled and linked against libiscsi.
2529 ETEXI
2536 STEXI
2538 iSCSI parameters such as username and password can also be specified via
2539 a configuration file. See qemu-doc for more information and examples.
2541 @item NBD
2542 QEMU supports NBD (Network Block Devices) both using TCP protocol as well
2543 as Unix Domain Sockets.
2545 Syntax for specifying a NBD device using TCP
2546 ``nbd:<server-ip>:<port>[:exportname=<export>]''
2548 Syntax for specifying a NBD device using Unix Domain Sockets
2549 ``nbd:unix:<domain-socket>[:exportname=<export>]''
2552 Example for TCP
2553 @example
2554 qemu-system-i386 --drive file=nbd:192.0.2.1:30000
2555 @end example
2557 Example for Unix Domain Sockets
2558 @example
2559 qemu-system-i386 --drive file=nbd:unix:/tmp/nbd-socket
2560 @end example
2562 @item SSH
2563 QEMU supports SSH (Secure Shell) access to remote disks.
2565 Examples:
2566 @example
2567 qemu-system-i386 -drive file=ssh://user@@host/path/to/disk.img
2568 qemu-system-i386 -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img
2569 @end example
2571 Currently authentication must be done using ssh-agent. Other
2572 authentication methods may be supported in future.
2574 @item Sheepdog
2575 Sheepdog is a distributed storage system for QEMU.
2576 QEMU supports using either local sheepdog devices or remote networked
2577 devices.
2579 Syntax for specifying a sheepdog device
2580 @example
2581 sheepdog[+tcp|+unix]://[host:port]/vdiname[?socket=path][#snapid|#tag]
2582 @end example
2584 Example
2585 @example
2586 qemu-system-i386 --drive file=sheepdog://192.0.2.1:30000/MyVirtualMachine
2587 @end example
2589 See also @url{http://http://www.osrg.net/sheepdog/}.
2591 @item GlusterFS
2592 GlusterFS is an user space distributed file system.
2593 QEMU supports the use of GlusterFS volumes for hosting VM disk images using
2594 TCP, Unix Domain Sockets and RDMA transport protocols.
2596 Syntax for specifying a VM disk image on GlusterFS volume is
2597 @example
2599 URI:
2600 gluster[+type]://[host[:port]]/volume/path[?socket=...][,debug=N][,logfile=...]
2602 JSON:
2603 'json:@{"driver":"qcow2","file":@{"driver":"gluster","volume":"testvol","path":"a.img","debug":N,"logfile":"...",
2606 @end example
2609 Example
2610 @example
2611 URI:
2612 qemu-system-x86_64 --drive file=gluster://192.0.2.1/testvol/a.img,
2613 @ file.debug=9,file.logfile=/var/log/qemu-gluster.log
2615 JSON:
2622 qemu-system-x86_64 -drive driver=qcow2,file.driver=gluster,file.volume=testvol,file.path=/path/a.img,
2623 @ file.debug=9,file.logfile=/var/log/qemu-gluster.log,
2624 @ file.server.0.type=tcp,file.server.0.host=1.2.3.4,file.server.0.port=24007,
2625 @ file.server.1.type=unix,file.server.1.socket=/var/run/glusterd.socket
2626 @end example
2628 See also @url{http://www.gluster.org}.
2630 @item HTTP/HTTPS/FTP/FTPS
2631 QEMU supports read-only access to files accessed over http(s) and ftp(s).
2633 Syntax using a single filename:
2634 @example
2635 <protocol>://[<username>[:<password>]@@]<host>/<path>
2636 @end example
2638 where:
2639 @table @option
2640 @item protocol
2641 'http', 'https', 'ftp', or 'ftps'.
2643 @item username
2644 Optional username for authentication to the remote server.
2646 @item password
2647 Optional password for authentication to the remote server.
2649 @item host
2650 Address of the remote server.
2652 @item path
2653 Path on the remote server, including any query string.
2654 @end table
2656 The following options are also supported:
2657 @table @option
2658 @item url
2659 The full URL when passing options to the driver explicitly.
2661 @item readahead
2662 The amount of data to read ahead with each range request to the remote server.
2663 This value may optionally have the suffix 'T', 'G', 'M', 'K', 'k' or 'b'. If it
2664 does not have a suffix, it will be assumed to be in bytes. The value must be a
2665 multiple of 512 bytes. It defaults to 256k.
2667 @item sslverify
2668 Whether to verify the remote server's certificate when connecting over SSL. It
2669 can have the value 'on' or 'off'. It defaults to 'on'.
2671 @item cookie
2672 Send this cookie (it can also be a list of cookies separated by ';') with
2673 each outgoing request. Only supported when using protocols such as HTTP
2674 which support cookies, otherwise ignored.
2676 @item timeout
2677 Set the timeout in seconds of the CURL connection. This timeout is the time
2678 that CURL waits for a response from the remote server to get the size of the
2679 image to be downloaded. If not set, the default timeout of 5 seconds is used.
2680 @end table
2682 Note that when passing options to qemu explicitly, @option{driver} is the value
2683 of <protocol>.
2685 Example: boot from a remote Fedora 20 live ISO image
2686 @example
2687 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
2689 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
2690 @end example
2692 Example: boot from a remote Fedora 20 cloud image using a local overlay for
2693 writes, copy-on-read, and a readahead of 64k
2694 @example
2695 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
2698 @end example
2703 @example
2704 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
2707 @end example
2708 ETEXI
2710 STEXI
2711 @end table
2712 ETEXI
2715 STEXI
2716 @table @option
2717 ETEXI
2729 QEMU_ARCH_ALL)
2730 STEXI
2732 @findex -bt
2735 example when emulating a machine with only one HCI built into it, only
2737 logic. The Transport Layer is decided by the machine type. Currently
2738 the machines @code{n800} and @code{n810} have one HCI and all other
2739 machines have none.
2741 @anchor{bt-hcis}
2742 The following three types are recognized:
2744 @table @option
2745 @item -bt hci,null
2746 (default) The corresponding Bluetooth HCI assumes no internal logic
2747 and will not respond to any HCI commands or emit events.
2749 @item -bt hci,host[:@var{id}]
2750 (@code{bluez} only) The corresponding HCI passes commands / events
2751 to / from the physical HCI identified by the name @var{id} (default:
2752 @code{hci0}) on the computer running QEMU. Only available on @code{bluez}
2753 capable systems like Linux.
2755 @item -bt hci[,vlan=@var{n}]
2756 Add a virtual, standard HCI that will participate in the Bluetooth
2757 scatternet @var{n} (default @code{0}). Similarly to @option{-net}
2758 VLANs, devices inside a bluetooth network @var{n} can only communicate
2759 with other devices in the same network (scatternet).
2760 @end table
2762 @item -bt vhci[,vlan=@var{n}]
2763 (Linux-host only) Create a HCI in scatternet @var{n} (default 0) attached
2764 to the host bluetooth stack instead of to the emulated target. This
2765 allows the host and target machines to participate in a common scatternet
2766 and communicate. Requires the Linux @code{vhci} driver installed. Can
2767 be used as following:
2769 @example
2770 qemu-system-i386 [...OPTIONS...] -bt hci,vlan=5 -bt vhci,vlan=5
2771 @end example
2773 @item -bt device:@var{dev}[,vlan=@var{n}]
2774 Emulate a bluetooth device @var{dev} and place it in network @var{n}
2775 (default @code{0}). QEMU can only emulate one type of bluetooth devices
2776 currently:
2778 @table @option
2779 @item keyboard
2780 Virtual wireless keyboard implementing the HIDP bluetooth profile.
2781 @end table
2782 ETEXI
2784 STEXI
2785 @end table
2786 ETEXI
2787 DEFHEADING()
2789 #ifdef CONFIG_TPM
2790 DEFHEADING(TPM device options:)
2792 DEF("tpmdev", HAS_ARG, QEMU_OPTION_tpmdev, \
2797 QEMU_ARCH_ALL)
2798 STEXI
2800 The general form of a TPM device option is:
2801 @table @option
2803 @item -tpmdev @var{backend} ,id=@var{id} [,@var{options}]
2804 @findex -tpmdev
2805 Backend type must be:
2806 @option{passthrough}.
2808 The specific backend type will determine the applicable options.
2809 The @code{-tpmdev} option creates the TPM backend and requires a
2810 @code{-device} option that specifies the TPM frontend interface model.
2812 Options to each backend are described below.
2814 Use 'help' to print all available TPM backend types.
2815 @example
2816 qemu -tpmdev help
2817 @end example
2819 @item -tpmdev passthrough, id=@var{id}, path=@var{path}, cancel-path=@var{cancel-path}
2821 (Linux-host only) Enable access to the host's TPM using the passthrough
2822 driver.
2824 @option{path} specifies the path to the host's TPM device, i.e., on
2825 a Linux host this would be @code{/dev/tpm0}.
2826 @option{path} is optional and by default @code{/dev/tpm0} is used.
2828 @option{cancel-path} specifies the path to the host TPM device's sysfs
2829 entry allowing for cancellation of an ongoing TPM command.
2830 @option{cancel-path} is optional and by default QEMU will search for the
2831 sysfs entry to use.
2833 Some notes about using the host's TPM with the passthrough driver:
2835 The TPM device accessed by the passthrough driver must not be
2836 used by any other application on the host.
2838 Since the host's firmware (BIOS/UEFI) has already initialized the TPM,
2839 the VM's firmware (BIOS/UEFI) will not be able to initialize the
2840 TPM again and may therefore not show a TPM-specific menu that would
2841 otherwise allow the user to configure the TPM, e.g., allow the user to
2842 enable/disable or activate/deactivate the TPM.
2843 Further, if TPM ownership is released from within a VM then the host's TPM
2844 will get disabled and deactivated. To enable and activate the
2845 TPM again afterwards, the host has to be rebooted and the user is
2846 required to enter the firmware's menu to enable and activate the TPM.
2847 If the TPM is left disabled and/or deactivated most TPM commands will fail.
2849 To create a passthrough TPM use the following two options:
2850 @example
2851 -tpmdev passthrough,id=tpm0 -device tpm-tis,tpmdev=tpm0
2852 @end example
2853 Note that the @code{-tpmdev} id is @code{tpm0} and is referenced by
2854 @code{tpmdev=tpm0} in the device option.
2856 @end table
2858 ETEXI
2860 DEFHEADING()
2862 #endif
2864 DEFHEADING(Linux/Multiboot boot specific:)
2865 STEXI
2867 When using these options, you can use a given Linux or Multiboot
2868 kernel without installing it in the disk image. It can be useful
2869 for easier testing of various kernels.
2871 @table @option
2872 ETEXI
2876 STEXI
2877 @item -kernel @var{bzImage}
2878 @findex -kernel
2879 Use @var{bzImage} as kernel image. The kernel can be either a Linux kernel
2880 or in multiboot format.
2881 ETEXI
2885 STEXI
2886 @item -append @var{cmdline}
2887 @findex -append
2888 Use @var{cmdline} as kernel command line
2889 ETEXI
2893 STEXI
2894 @item -initrd @var{file}
2895 @findex -initrd
2896 Use @var{file} as initial ram disk.
2900 This syntax is only available with multiboot.
2902 Use @var{file1} and @var{file2} as modules and pass arg=foo as parameter to the
2903 first module.
2904 ETEXI
2908 STEXI
2909 @item -dtb @var{file}
2910 @findex -dtb
2911 Use @var{file} as a device tree binary (dtb) image and pass it to the kernel
2912 on boot.
2913 ETEXI
2915 STEXI
2916 @end table
2917 ETEXI
2918 DEFHEADING()
2920 DEFHEADING(Debug/Expert options:)
2921 STEXI
2922 @table @option
2923 ETEXI
2930 QEMU_ARCH_ALL)
2931 STEXI
2933 @item -fw_cfg [name=]@var{name},file=@var{file}
2934 @findex -fw_cfg
2935 Add named fw_cfg entry with contents from file @var{file}.
2937 @item -fw_cfg [name=]@var{name},string=@var{str}
2938 Add named fw_cfg entry with contents from string @var{str}.
2940 The terminating NUL character of the contents of @var{str} will not be
2941 included as part of the fw_cfg item data. To insert contents with
2942 embedded NUL characters, you have to use the @var{file} parameter.
2944 The fw_cfg entries are passed by QEMU through to the guest.
2946 Example:
2947 @example
2948 -fw_cfg name=opt/com.mycompany/blob,file=./my_blob.bin
2949 @end example
2950 creates an fw_cfg entry named opt/com.mycompany/blob with contents
2951 from ./my_blob.bin.
2953 ETEXI
2957 QEMU_ARCH_ALL)
2958 STEXI
2959 @item -serial @var{dev}
2960 @findex -serial
2961 Redirect the virtual serial port to host character device
2962 @var{dev}. The default device is @code{vc} in graphical mode and
2963 @code{stdio} in non graphical mode.
2965 This option can be used several times to simulate up to 4 serial
2966 ports.
2968 Use @code{-serial none} to disable all serial ports.
2970 Available character devices are:
2971 @table @option
2972 @item vc[:@var{W}x@var{H}]
2973 Virtual console. Optionally, a width and height can be given in pixel with
2974 @example
2975 vc:800x600
2976 @end example
2977 It is also possible to specify width or height in characters:
2978 @example
2979 vc:80Cx24C
2980 @end example
2981 @item pty
2982 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
2983 @item none
2984 No device is allocated.
2985 @item null
2986 void device
2987 @item chardev:@var{id}
2988 Use a named character device defined with the @code{-chardev} option.
2989 @item /dev/XXX
2990 [Linux only] Use host tty, e.g. @file{/dev/ttyS0}. The host serial port
2991 parameters are set according to the emulated ones.
2992 @item /dev/parport@var{N}
2993 [Linux only, parallel port only] Use host parallel port
2994 @var{N}. Currently SPP and EPP parallel port features can be used.
2995 @item file:@var{filename}
2996 Write output to @var{filename}. No character can be read.
2997 @item stdio
2998 [Unix only] standard input/output
2999 @item pipe:@var{filename}
3000 name pipe @var{filename}
3001 @item COM@var{n}
3002 [Windows only] Use host serial port @var{n}
3003 @item udp:[@var{remote_host}]:@var{remote_port}[@@[@var{src_ip}]:@var{src_port}]
3004 This implements UDP Net Console.
3005 When @var{remote_host} or @var{src_ip} are not specified
3006 they default to @code{0.0.0.0}.
3007 When not using a specified @var{src_port} a random port is automatically chosen.
3009 If you just want a simple readonly console you can use @code{netcat} or
3010 @code{nc}, by starting QEMU with: @code{-serial udp::4555} and nc as:
3011 @code{nc -u -l -p 4555}. Any time QEMU writes something to that port it
3012 will appear in the netconsole session.
3014 If you plan to send characters back via netconsole or you want to stop
3015 and start QEMU a lot of times, you should have QEMU use the same
3016 source port each time by using something like @code{-serial
3017 udp::4555@@:4556} to QEMU. Another approach is to use a patched
3018 version of netcat which can listen to a TCP port and send and receive
3019 characters via udp. If you have a patched version of netcat which
3020 activates telnet remote echo and single char transfer, then you can
3021 use the following options to step up a netcat redirector to allow
3022 telnet on port 5555 to access the QEMU port.
3023 @table @code
3024 @item QEMU Options:
3025 -serial udp::4555@@:4556
3026 @item netcat options:
3027 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
3028 @item telnet options:
3029 localhost 5555
3030 @end table
3032 @item tcp:[@var{host}]:@var{port}[,@var{server}][,nowait][,nodelay][,reconnect=@var{seconds}]
3033 The TCP Net Console has two modes of operation. It can send the serial
3034 I/O to a location or wait for a connection from a location. By default
3035 the TCP Net Console is sent to @var{host} at the @var{port}. If you use
3036 the @var{server} option QEMU will wait for a client socket application
3037 to connect to the port before continuing, unless the @code{nowait}
3038 option was specified. The @code{nodelay} option disables the Nagle buffering
3039 algorithm. The @code{reconnect} option only applies if @var{noserver} is
3040 set, if the connection goes down it will attempt to reconnect at the
3041 given interval. If @var{host} is omitted, 0.0.0.0 is assumed. Only
3042 one TCP connection at a time is accepted. You can use @code{telnet} to
3043 connect to the corresponding character device.
3044 @table @code
3045 @item Example to send tcp console to 192.168.0.2 port 4444
3046 -serial tcp:192.168.0.2:4444
3047 @item Example to listen and wait on port 4444 for connection
3048 -serial tcp::4444,server
3049 @item Example to not wait and listen on ip 192.168.0.100 port 4444
3050 -serial tcp:192.168.0.100:4444,server,nowait
3051 @end table
3053 @item telnet:@var{host}:@var{port}[,server][,nowait][,nodelay]
3054 The telnet protocol is used instead of raw tcp sockets. The options
3055 work the same as if you had specified @code{-serial tcp}. The
3056 difference is that the port acts like a telnet server or client using
3057 telnet option negotiation. This will also allow you to send the
3058 MAGIC_SYSRQ sequence if you use a telnet that supports sending the break
3059 sequence. Typically in unix telnet you do it with Control-] and then
3062 @item unix:@var{path}[,server][,nowait][,reconnect=@var{seconds}]
3063 A unix domain socket is used instead of a tcp socket. The option works the
3064 same as if you had specified @code{-serial tcp} except the unix domain socket
3065 @var{path} is used for connections.
3067 @item mon:@var{dev_string}
3068 This is a special option to allow the monitor to be multiplexed onto
3069 another serial port. The monitor is accessed with key sequence of
3070 @key{Control-a} and then pressing @key{c}.
3071 @var{dev_string} should be any one of the serial devices specified
3072 above. An example to multiplex the monitor onto a telnet server
3073 listening on port 4444 would be:
3074 @table @code
3075 @item -serial mon:telnet::4444,server,nowait
3076 @end table
3077 When the monitor is multiplexed to stdio in this way, Ctrl+C will not terminate
3078 QEMU any more but will be passed to the guest instead.
3080 @item braille
3081 Braille device. This will use BrlAPI to display the braille output on a real
3082 or fake device.
3084 @item msmouse
3085 Three button serial mouse. Configure the guest to use Microsoft protocol.
3086 @end table
3087 ETEXI
3091 QEMU_ARCH_ALL)
3092 STEXI
3093 @item -parallel @var{dev}
3094 @findex -parallel
3095 Redirect the virtual parallel port to host device @var{dev} (same
3096 devices as the serial port). On Linux hosts, @file{/dev/parportN} can
3097 be used to use hardware devices connected on the corresponding host
3098 parallel port.
3100 This option can be used several times to simulate up to 3 parallel
3101 ports.
3103 Use @code{-parallel none} to disable all parallel ports.
3104 ETEXI
3108 QEMU_ARCH_ALL)
3109 STEXI
3110 @item -monitor @var{dev}
3111 @findex -monitor
3112 Redirect the monitor to host device @var{dev} (same devices as the
3113 serial port).
3114 The default device is @code{vc} in graphical mode and @code{stdio} in
3115 non graphical mode.
3116 Use @code{-monitor none} to disable the default monitor.
3117 ETEXI
3120 QEMU_ARCH_ALL)
3121 STEXI
3122 @item -qmp @var{dev}
3123 @findex -qmp
3124 Like -monitor but opens in 'control' mode.
3125 ETEXI
3128 QEMU_ARCH_ALL)
3129 STEXI
3130 @item -qmp-pretty @var{dev}
3131 @findex -qmp-pretty
3132 Like -qmp but uses pretty JSON formatting.
3133 ETEXI
3137 STEXI
3138 @item -mon [chardev=]name[,mode=readline|control]
3139 @findex -mon
3140 Setup monitor on chardev @var{name}.
3141 ETEXI
3145 QEMU_ARCH_ALL)
3146 STEXI
3147 @item -debugcon @var{dev}
3148 @findex -debugcon
3149 Redirect the debug console to host device @var{dev} (same devices as the
3150 serial port). The debug console is an I/O port which is typically port
3151 0xe9; writing to that I/O port sends output to this device.
3152 The default device is @code{vc} in graphical mode and @code{stdio} in
3153 non graphical mode.
3154 ETEXI
3158 STEXI
3159 @item -pidfile @var{file}
3160 @findex -pidfile
3161 Store the QEMU process PID in @var{file}. It is useful if you launch QEMU
3162 from a script.
3163 ETEXI
3167 STEXI
3168 @item -singlestep
3169 @findex -singlestep
3170 Run the emulation in single step mode.
3171 ETEXI
3175 QEMU_ARCH_ALL)
3176 STEXI
3177 @item -S
3178 @findex -S
3179 Do not start CPU at startup (you must type 'c' in the monitor).
3180 ETEXI
3186 QEMU_ARCH_ALL)
3187 STEXI
3188 @item -realtime mlock=on|off
3189 @findex -realtime
3190 Run qemu with realtime features.
3191 mlocking qemu and guest memory can be enabled via @option{mlock=on}
3192 (enabled by default).
3193 ETEXI
3197 STEXI
3198 @item -gdb @var{dev}
3199 @findex -gdb
3200 Wait for gdb connection on device @var{dev} (@pxref{gdb_usage}). Typical
3201 connections will likely be TCP-based, but also UDP, pseudo TTY, or even
3202 stdio are reasonable use case. The latter is allowing to start QEMU from
3203 within gdb and establish the connection via a pipe:
3204 @example
3205 (gdb) target remote | exec qemu-system-i386 -gdb stdio ...
3206 @end example
3207 ETEXI
3211 QEMU_ARCH_ALL)
3212 STEXI
3213 @item -s
3214 @findex -s
3215 Shorthand for -gdb tcp::1234, i.e. open a gdbserver on TCP port 1234
3216 (@pxref{gdb_usage}).
3217 ETEXI
3221 QEMU_ARCH_ALL)
3222 STEXI
3223 @item -d @var{item1}[,...]
3224 @findex -d
3225 Enable logging of specified items. Use '-d help' for a list of log items.
3226 ETEXI
3230 QEMU_ARCH_ALL)
3231 STEXI
3232 @item -D @var{logfile}
3233 @findex -D
3234 Output log in @var{logfile} instead of to stderr
3235 ETEXI
3238 "-dfilter range,.. filter debug output to range of addresses (useful for -d cpu,exec,etc..)\n",
3239 QEMU_ARCH_ALL)
3240 STEXI
3241 @item -dfilter @var{range1}[,...]
3242 @findex -dfilter
3243 Filter debug output to that relevant to a range of target addresses. The filter
3244 spec can be either @var{start}+@var{size}, @var{start}-@var{size} or
3245 @var{start}..@var{end} where @var{start} @var{end} and @var{size} are the
3246 addresses and sizes required. For example:
3247 @example
3248 -dfilter 0x8000..0x8fff,0xffffffc000080000+0x200,0xffffffc000060000-0x1000
3249 @end example
3250 Will dump output for any code in the 0x1000 sized block starting at 0x8000 and
3251 the 0x200 sized block starting at 0xffffffc000080000 and another 0x1000 sized
3252 block starting at 0xffffffc00005f000.
3253 ETEXI
3257 QEMU_ARCH_ALL)
3258 STEXI
3259 @item -L @var{path}
3260 @findex -L
3261 Set the directory for the BIOS, VGA BIOS and keymaps.
3263 To list all the data directories, use @code{-L help}.
3264 ETEXI
3268 STEXI
3269 @item -bios @var{file}
3270 @findex -bios
3271 Set the filename for the BIOS.
3272 ETEXI
3276 STEXI
3277 @item -enable-kvm
3278 @findex -enable-kvm
3279 Enable KVM full virtualization support. This option is only available
3280 if KVM support is enabled when compiling.
3281 ETEXI
3288 QEMU_ARCH_ALL)
3292 QEMU_ARCH_ALL)
3293 STEXI
3294 @item -xen-domid @var{id}
3295 @findex -xen-domid
3296 Specify xen guest domain @var{id} (XEN only).
3297 @item -xen-create
3298 @findex -xen-create
3299 Create domain using xen hypercalls, bypassing xend.
3300 Warning: should not be used when xend is in use (XEN only).
3301 @item -xen-attach
3302 @findex -xen-attach
3303 Attach to existing xen domain.
3304 xend will use this when starting QEMU (XEN only).
3305 ETEXI
3309 STEXI
3310 @item -no-reboot
3311 @findex -no-reboot
3312 Exit instead of rebooting.
3313 ETEXI
3317 STEXI
3318 @item -no-shutdown
3319 @findex -no-shutdown
3320 Don't exit QEMU on guest shutdown, but instead only stop the emulation.
3321 This allows for instance switching to monitor to commit changes to the
3322 disk image.
3323 ETEXI
3328 QEMU_ARCH_ALL)
3329 STEXI
3330 @item -loadvm @var{file}
3331 @findex -loadvm
3332 Start right away with a saved state (@code{loadvm} in monitor)
3333 ETEXI
3335 #ifndef _WIN32
3338 #endif
3339 STEXI
3340 @item -daemonize
3341 @findex -daemonize
3342 Daemonize the QEMU process after initialization. QEMU will not detach from
3343 standard IO until it is ready to receive connections on any of its devices.
3344 This option is a useful way for external programs to launch QEMU without having
3345 to cope with initialization race conditions.
3346 ETEXI
3350 QEMU_ARCH_ALL)
3351 STEXI
3352 @item -option-rom @var{file}
3353 @findex -option-rom
3354 Load the contents of @var{file} as an option ROM.
3355 This option is useful to load things like EtherBoot.
3356 ETEXI
3358 HXCOMM Silently ignored for compatibility
3361 HXCOMM Options deprecated by -rtc
3368 QEMU_ARCH_ALL)
3370 STEXI
3372 @item -rtc [base=utc|localtime|@var{date}][,clock=host|vm][,driftfix=none|slew]
3373 @findex -rtc
3374 Specify @option{base} as @code{utc} or @code{localtime} to let the RTC start at the current
3375 UTC or local time, respectively. @code{localtime} is required for correct date in
3376 MS-DOS or Windows. To start at a specific point in time, provide @var{date} in the
3377 format @code{2006-06-17T16:01:21} or @code{2006-06-17}. The default base is UTC.
3379 By default the RTC is driven by the host system time. This allows using of the
3380 RTC as accurate reference clock inside the guest, specifically if the host
3381 time is smoothly following an accurate external reference clock, e.g. via NTP.
3382 If you want to isolate the guest time from the host, you can set @option{clock}
3383 to @code{rt} instead. To even prevent it from progressing during suspension,
3384 you can set it to @code{vm}.
3386 Enable @option{driftfix} (i386 targets only) if you experience time drift problems,
3387 specifically with Windows' ACPI HAL. This option will try to figure out how
3388 many timer interrupts were not processed by the Windows guest and will
3389 re-inject them.
3390 ETEXI
3397 STEXI
3398 @item -icount [shift=@var{N}|auto][,rr=record|replay,rrfile=@var{filename}]
3399 @findex -icount
3400 Enable virtual instruction counter. The virtual cpu will execute one
3401 instruction every 2^@var{N} ns of virtual time. If @code{auto} is specified
3402 then the virtual cpu speed will be automatically adjusted to keep virtual
3403 time within a few seconds of real time.
3405 When the virtual cpu is sleeping, the virtual time will advance at default
3406 speed unless @option{sleep=on|off} is specified.
3407 With @option{sleep=on|off}, the virtual time will jump to the next timer deadline
3408 instantly whenever the virtual cpu goes to sleep mode and will not advance
3409 if no timer is enabled. This behavior give deterministic execution times from
3410 the guest point of view.
3412 Note that while this option can give deterministic behavior, it does not
3413 provide cycle accurate emulation. Modern CPUs contain superscalar out of
3414 order cores with complex cache hierarchies. The number of instructions
3415 executed often has little or no correlation with actual performance.
3417 @option{align=on} will activate the delay algorithm which will try
3418 to synchronise the host clock and the virtual clock. The goal is to
3419 have a guest running at the real frequency imposed by the shift option.
3420 Whenever the guest clock is behind the host clock and if
3421 @option{align=on} is specified then we print a message to the user
3422 to inform about the delay.
3423 Currently this option does not work when @option{shift} is @code{auto}.
3424 Note: The sync algorithm will work for those shift values for which
3425 the guest clock runs ahead of the host clock. Typically this happens
3426 when the shift value is high (how high depends on the host machine).
3428 When @option{rr} option is specified deterministic record/replay is enabled.
3429 Replay log is written into @var{filename} file in record mode and
3430 read from this file in replay mode.
3431 ETEXI
3436 QEMU_ARCH_ALL)
3437 STEXI
3438 @item -watchdog @var{model}
3439 @findex -watchdog
3440 Create a virtual hardware watchdog device. Once enabled (by a guest
3441 action), the watchdog must be periodically polled by an agent inside
3442 the guest or else the guest will be restarted. Choose a model for
3443 which your guest has drivers.
3445 The @var{model} is the model of hardware watchdog to emulate. Use
3446 @code{-watchdog help} to list available hardware models. Only one
3447 watchdog can be enabled for a guest.
3449 The following models may be available:
3450 @table @option
3451 @item ib700
3452 iBASE 700 is a very simple ISA watchdog with a single timer.
3453 @item i6300esb
3454 Intel 6300ESB I/O controller hub is a much more featureful PCI-based
3455 dual-timer watchdog.
3456 @item diag288
3457 A virtual watchdog for s390x backed by the diagnose 288 hypercall
3458 (currently KVM only).
3459 @end table
3460 ETEXI
3465 QEMU_ARCH_ALL)
3466 STEXI
3467 @item -watchdog-action @var{action}
3468 @findex -watchdog-action
3470 The @var{action} controls what QEMU will do when the watchdog timer
3471 expires.
3472 The default is
3473 @code{reset} (forcefully reset the guest).
3474 Other possible actions are:
3475 @code{shutdown} (attempt to gracefully shutdown the guest),
3476 @code{poweroff} (forcefully poweroff the guest),
3477 @code{pause} (pause the guest),
3478 @code{debug} (print a debug message and continue), or
3479 @code{none} (do nothing).
3481 Note that the @code{shutdown} action requires that the guest responds
3482 to ACPI signals, which it may not be able to do in the sort of
3483 situations where the watchdog would have expired, and thus
3484 @code{-watchdog-action shutdown} is not recommended for production use.
3486 Examples:
3488 @table @code
3489 @item -watchdog i6300esb -watchdog-action pause
3490 @itemx -watchdog ib700
3491 @end table
3492 ETEXI
3496 QEMU_ARCH_ALL)
3497 STEXI
3499 @item -echr @var{numeric_ascii_value}
3500 @findex -echr
3501 Change the escape character used for switching to the monitor when using
3502 monitor and serial sharing. The default is @code{0x01} when using the
3503 @code{-nographic} option. @code{0x01} is equal to pressing
3504 @code{Control-a}. You can select a different character from the ascii
3505 control keys where 1 through 26 map to Control-a through Control-z. For
3506 instance you could use the either of the following to change the escape
3507 character to Control-t.
3508 @table @code
3509 @item -echr 0x14
3510 @itemx -echr 20
3511 @end table
3512 ETEXI
3517 STEXI
3518 @item -virtioconsole @var{c}
3519 @findex -virtioconsole
3520 Set virtio console.
3522 This option is maintained for backward compatibility.
3524 Please use @code{-device virtconsole} for the new way of invocation.
3525 ETEXI
3529 STEXI
3530 @item -show-cursor
3531 @findex -show-cursor
3532 Show cursor.
3533 ETEXI
3537 STEXI
3538 @item -tb-size @var{n}
3539 @findex -tb-size
3540 Set TB size.
3541 ETEXI
3555 QEMU_ARCH_ALL)
3556 STEXI
3557 @item -incoming tcp:[@var{host}]:@var{port}[,to=@var{maxport}][,ipv4][,ipv6]
3558 @itemx -incoming rdma:@var{host}:@var{port}[,ipv4][,ipv6]
3559 @findex -incoming
3560 Prepare for incoming migration, listen on a given tcp port.
3562 @item -incoming unix:@var{socketpath}
3563 Prepare for incoming migration, listen on a given unix socket.
3565 @item -incoming fd:@var{fd}
3566 Accept incoming migration from a given filedescriptor.
3568 @item -incoming exec:@var{cmdline}
3569 Accept incoming migration as an output from specified external command.
3571 @item -incoming defer
3572 Wait for the URI to be specified via migrate_incoming. The monitor can
3573 be used to change settings (such as migration parameters) prior to issuing
3574 the migrate_incoming to allow the migration to begin.
3575 ETEXI
3579 STEXI
3580 @item -nodefaults
3581 @findex -nodefaults
3586 ETEXI
3588 #ifndef _WIN32
3591 QEMU_ARCH_ALL)
3592 #endif
3593 STEXI
3595 @findex -chroot
3596 Immediately before starting guest execution, chroot to the specified
3598 ETEXI
3600 #ifndef _WIN32
3603 QEMU_ARCH_ALL)
3604 #endif
3605 STEXI
3607 @findex -runas
3609 to the specified user.
3610 ETEXI
3615 QEMU_ARCH_PPC | QEMU_ARCH_SPARC)
3616 STEXI
3620 ETEXI
3623 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3624 QEMU_ARCH_MIPS)
3625 STEXI
3626 @item -semihosting
3627 @findex -semihosting
3629 ETEXI
3633 QEMU_ARCH_ARM | QEMU_ARCH_M68K | QEMU_ARCH_XTENSA | QEMU_ARCH_LM32 |
3634 QEMU_ARCH_MIPS)
3635 STEXI
3639 @table @option
3645 Allows the user to pass input arguments, and can be used multiple times to build
3650 @end table
3651 ETEXI
3654 STEXI
3658 ETEXI
3662 QEMU_ARCH_ALL)
3663 STEXI
3665 @findex -sandbox
3668 ETEXI
3672 STEXI
3674 @findex -readconfig
3676 QEMU process with many command line options but you don't want to exceed the command line
3677 character limit.
3678 ETEXI
3679 DEF("writeconfig", HAS_ARG, QEMU_OPTION_writeconfig,
3682 STEXI
3683 @item -writeconfig @var{file}
3684 @findex -writeconfig
3685 Write device configuration to @var{file}. The @var{file} can be either filename to save
3686 command line and device configuration into file or dash @code{-}) character to print the
3687 output to stdout. This can be later used as input file for @code{-readconfig} option.
3688 ETEXI
3689 DEF("nodefconfig", 0, QEMU_OPTION_nodefconfig,
3692 QEMU_ARCH_ALL)
3693 STEXI
3694 @item -nodefconfig
3695 @findex -nodefconfig
3696 Normally QEMU loads configuration files from @var{sysconfdir} and @var{datadir} at startup.
3697 The @code{-nodefconfig} option will prevent QEMU from loading any of those config files.
3698 ETEXI
3699 DEF("no-user-config", 0, QEMU_OPTION_nouserconfig,
3702 QEMU_ARCH_ALL)
3703 STEXI
3704 @item -no-user-config
3705 @findex -no-user-config
3706 The @code{-no-user-config} option makes QEMU not load any of the user-provided
3709 ETEXI
3713 QEMU_ARCH_ALL)
3714 STEXI
3716 HXCOMM HX does not support conditional compilation of text.
3720 ETEXI
3722 HXCOMM Internal use
3726 #ifdef __linux__
3729 QEMU_ARCH_ALL)
3730 #endif
3731 STEXI
3735 ETEXI
3740 HXCOMM Deprecated by kvm-pit driver properties
3757 QEMU_ARCH_ALL)
3758 STEXI
3760 @findex -msg
3762 ETEXI
3770 QEMU_ARCH_ALL)
3771 STEXI
3776 ETEXI
3786 QEMU_ARCH_ALL)
3787 STEXI
3789 @findex -object
3795 @table @option
3797 @item -object memory-backend-file,id=@var{id},size=@var{size},mem-path=@var{dir},share=@var{on|off}
3799 Creates a memory file backend object, which can be used to back
3801 unique ID that will be used to reference this memory region
3803 option provides the size of the memory region, and accepts
3805 the path to either a shared memory or huge page filesystem mount.
3812 Creates a random number generator backend which obtains entropy from
3820 Creates a random number generator backend which obtains entropy from
3822 a unique ID that will be used to reference this entropy backend from
3824 the unique ID of a character device backend that provides the connection
3825 to the RNG daemon.
3827 @item -object tls-creds-anon,id=@var{id},endpoint=@var{endpoint},dir=@var{/path/to/cred/dir},verify-peer=@var{on|off}
3829 Creates a TLS anonymous credentials object, which can be used to provide
3831 ID which network backends will use to access the credentials. The
3833 on whether the QEMU network backend that uses the credentials will be
3842 a set of DH parameters at startup. This is a computationally
3843 expensive operation that consumes random pool entropy, so it is
3844 recommended that a persistent set of parameters be generated
3845 upfront and saved.
3847 @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}
3849 Creates a TLS anonymous credentials object, which can be used to provide
3851 ID which network backends will use to access the credentials. The
3853 on whether the QEMU network backend that uses the credentials will be
3857 must be provided with valid client certificates too.
3863 a set of DH parameters at startup. This is a computationally
3864 expensive operation that consumes random pool entropy, so it is
3865 recommended that a persistent set of parameters be generated
3866 upfront and saved.
3868 For x509 certificate credentials the directory will contain further files
3869 providing the x509 certificates. The certificates must be stored
3880 @item -object filter-buffer,id=@var{id},netdev=@var{netdevid},interval=@var{t}[,queue=@var{all|rx|tx}][,status=@var{on|off}]
3883 packets arriving in a given interval on netdev @var{netdevid} are delayed
3884 until the end of the interval. Interval is in microseconds.
3885 @option{status} is optional that indicate whether the netfilter is
3888 queue @var{all|rx|tx} is an option that can be applied to any netfilter.
3890 @option{all}: the filter is attached both to the receive and the transmit
3891 queue of the netdev (default).
3893 @option{rx}: the filter is attached to the receive queue of the netdev,
3894 where it will receive packets sent to the netdev.
3896 @option{tx}: the filter is attached to the transmit queue of the netdev,
3897 where it will receive packets sent by the netdev.
3899 @item -object filter-mirror,id=@var{id},netdev=@var{netdevid},outdev=@var{chardevid}[,queue=@var{all|rx|tx}]
3901 filter-mirror on netdev @var{netdevid},mirror net packet to chardev
3902 @var{chardevid}
3904 @item -object filter-redirector,id=@var{id},netdev=@var{netdevid},indev=@var{chardevid},
3905 outdev=@var{chardevid}[,queue=@var{all|rx|tx}]
3907 filter-redirector on netdev @var{netdevid},redirect filter's net packet to chardev
3909 Create a filter-redirector we need to differ outdev id from indev id, id can not
3910 be the same. we can just use indev or outdev, but at least one of indev or outdev
3911 need to be specified.
3913 @item -object filter-rewriter,id=@var{id},netdev=@var{netdevid},rewriter-mode=@var{mode}[,queue=@var{all|rx|tx}]
3915 Filter-rewriter is a part of COLO project.It will rewrite tcp packet to
3916 secondary from primary to keep secondary tcp connection,and rewrite
3917 tcp packet to primary from secondary make tcp packet can be handled by
3918 client.
3920 usage:
3921 colo secondary:
3922 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
3923 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
3924 -object filter-rewriter,id=rew0,netdev=hn0,queue=all
3926 @item -object filter-dump,id=@var{id},netdev=@var{dev}[,file=@var{filename}][,maxlen=@var{len}]
3928 Dump the network traffic on netdev @var{dev} to the file specified by
3929 @var{filename}. At most @var{len} bytes (64k by default) per packet are stored.
3930 The file format is libpcap, so it can be analyzed with tools such as tcpdump
3931 or Wireshark.
3933 @item -object colo-compare,id=@var{id},primary_in=@var{chardevid},secondary_in=@var{chardevid},
3934 outdev=@var{chardevid}
3936 Colo-compare gets packet from primary_in@var{chardevid} and secondary_in@var{chardevid}, than compare primary packet with
3937 secondary packet. If the packets are same, we will output primary
3938 packet to outdev@var{chardevid}, else we will notify colo-frame
3939 do checkpoint and send primary packet to outdev@var{chardevid}.
3941 we must use it with the help of filter-mirror and filter-redirector.
3943 @example
3945 primary:
3946 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown
3947 -device e1000,id=e0,netdev=hn0,mac=52:a4:00:12:78:66
3948 -chardev socket,id=mirror0,host=3.3.3.3,port=9003,server,nowait
3949 -chardev socket,id=compare1,host=3.3.3.3,port=9004,server,nowait
3950 -chardev socket,id=compare0,host=3.3.3.3,port=9001,server,nowait
3951 -chardev socket,id=compare0-0,host=3.3.3.3,port=9001
3952 -chardev socket,id=compare_out,host=3.3.3.3,port=9005,server,nowait
3953 -chardev socket,id=compare_out0,host=3.3.3.3,port=9005
3954 -object filter-mirror,id=m0,netdev=hn0,queue=tx,outdev=mirror0
3955 -object filter-redirector,netdev=hn0,id=redire0,queue=rx,indev=compare_out
3956 -object filter-redirector,netdev=hn0,id=redire1,queue=rx,outdev=compare0
3957 -object colo-compare,id=comp0,primary_in=compare0-0,secondary_in=compare1,outdev=compare_out0
3959 secondary:
3960 -netdev tap,id=hn0,vhost=off,script=/etc/qemu-ifup,down script=/etc/qemu-ifdown
3961 -device e1000,netdev=hn0,mac=52:a4:00:12:78:66
3962 -chardev socket,id=red0,host=3.3.3.3,port=9003
3963 -chardev socket,id=red1,host=3.3.3.3,port=9004
3964 -object filter-redirector,id=f1,netdev=hn0,queue=tx,indev=red0
3965 -object filter-redirector,id=f2,netdev=hn0,queue=rx,outdev=red1
3967 @end example
3969 If you want to know the detail of above command line, you can read
3970 the colo-compare git log.
3972 @item -object cryptodev-backend-builtin,id=@var{id}[,queues=@var{queues}]
3974 Creates a cryptodev backend which executes crypto opreation from
3975 the QEMU cipher APIS. The @var{id} parameter is
3976 a unique ID that will be used to reference this cryptodev backend from
3977 the @option{virtio-crypto} device. The @var{queues} parameter is optional,
3978 which specify the queue number of cryptodev backend, the default of
3979 @var{queues} is 1.
3981 @example
3983 # qemu-system-x86_64 \
3984 [...] \
3985 -object cryptodev-backend-builtin,id=cryptodev0 \
3986 -device virtio-crypto-pci,id=crypto0,cryptodev=cryptodev0 \
3987 [...]
3988 @end example
3990 @item -object secret,id=@var{id},data=@var{string},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
3991 @item -object secret,id=@var{id},file=@var{filename},format=@var{raw|base64}[,keyid=@var{secretid},iv=@var{string}]
3993 Defines a secret to store a password, encryption key, or some other sensitive
3994 data. The sensitive data can either be passed directly via the @var{data}
3995 parameter, or indirectly via the @var{file} parameter. Using the @var{data}
3996 parameter is insecure unless the sensitive data is encrypted.
3998 The sensitive data can be provided in raw format (the default), or base64.
3999 When encoded as JSON, the raw format only supports valid UTF-8 characters,
4000 so base64 is recommended for sending binary data. QEMU will convert from
4001 which ever format is provided to the format it needs internally. eg, an
4002 RBD password can be provided in raw format, even though it will be base64
4003 encoded when passed onto the RBD sever.
4005 For added protection, it is possible to encrypt the data associated with
4006 a secret using the AES-256-CBC cipher. Use of encryption is indicated
4007 by providing the @var{keyid} and @var{iv} parameters. The @var{keyid}
4008 parameter provides the ID of a previously defined secret that contains
4009 the AES-256 decryption key. This key should be 32-bytes long and be
4010 base64 encoded. The @var{iv} parameter provides the random initialization
4011 vector used for encryption of this particular secret and should be a
4012 base64 encrypted string of the 16-byte IV.
4014 The simplest (insecure) usage is to provide the secret inline
4016 @example
4018 # $QEMU -object secret,id=sec0,data=letmein,format=raw
4020 @end example
4022 The simplest secure usage is to provide the secret via a file
4024 # echo -n "letmein" > mypasswd.txt
4025 # $QEMU -object secret,id=sec0,file=mypasswd.txt,format=raw
4027 For greater security, AES-256-CBC should be used. To illustrate usage,
4028 consider the openssl command line tool which can encrypt the data. Note
4029 that when encrypting, the plaintext must be padded to the cipher block
4030 size (32 bytes) using the standard PKCS#5/6 compatible padding algorithm.
4032 First a master key needs to be created in base64 encoding:
4034 @example
4035 # openssl rand -base64 32 > key.b64
4037 @end example
4039 Each secret to be encrypted needs to have a random initialization vector
4040 generated. These do not need to be kept secret
4042 @example
4043 # openssl rand -base64 16 > iv.b64
4045 @end example
4047 The secret to be defined can now be encrypted, in this case we're
4048 telling openssl to base64 encode the result, but it could be left
4051 @example
4054 @end example
4057 and specify that to be used to decrypt the user password. Pass the
4060 @example
4061 # $QEMU \
4065 @end example
4067 @end table
4069 ETEXI
4073 STEXI
4074 @end table
4075 ETEXI