1QEMU(1) QEMU(1)
2
6 qemu-doc - QEMU Emulator User Documentation
7
9 usage: qemu [options] [disk_image]
10
12 The QEMU PC System emulator simulates the following peripherals:
13 - i440FX host PCI bridge and PIIX3 PCI to ISA bridge
15 - Cirrus CLGD 5446 PCI VGA card or dummy VGA card with Bochs VESA
17 extensions (hardware level, including all non standard modes).
18 - PS/2 mouse and keyboard
20 - 2 PCI IDE interfaces with hard disk and CD-ROM support
22 - Floppy disk
24 - NE2000 PCI network adapters
26 - Serial ports
28 - Creative SoundBlaster 16 sound card
30 - ENSONIQ AudioPCI ES1370 sound card
32 - Adlib(OPL2) - Yamaha YM3812 compatible chip
34 - PCI UHCI USB controller and a virtual USB hub.
36 SMP is supported with up to 255 CPUs.
38 Note that adlib is only available when QEMU was configured with
40 -enable-adlib
41 QEMU uses the PC BIOS from the Bochs project and the Plex86/Bochs LGPL
43 VGA BIOS.
44 QEMU uses YM3812 emulation by Tatsuyuki Satoh.
46
48 disk_image is a raw hard disk image for IDE hard disk 0.
49 General options:
51 -M machine
53 Select the emulated machine ("-M ?" for list)
54 -fda file
56 -fdb file
57 Use file as floppy disk 0/1 image. You can use the host floppy by
58 using /dev/fd0 as filename.
59 -hda file
61 -hdb file
62 -hdc file
63 -hdd file
64 Use file as hard disk 0, 1, 2 or 3 image.
65 -cdrom file
67 Use file as CD-ROM image (you cannot use -hdc and and -cdrom at the
68 same time). You can use the host CD-ROM by using /dev/cdrom as
69 filename.
70 -boot [a⎪c⎪d⎪n]
72 Boot on floppy (a), hard disk (c), CD-ROM (d), or Etherboot (n).
73 Hard disk boot is the default.
74 -snapshot
76 Write to temporary files instead of disk image files. In this case,
77 the raw disk image you use is not written back. You can however
78 force the write back by pressing C-a s.
79 -no-fd-bootchk
81 Disable boot signature checking for floppy disks in Bochs BIOS. It
82 may be needed to boot from old floppy disks.
83 -m megs
85 Set virtual RAM size to megs megabytes. Default is 128 MB.
86 -smp n
88 Simulate an SMP system with n CPUs. On the PC target, up to 255
89 CPUs are supported.
90 -nographic
92 Normally, QEMU uses SDL to display the VGA output. With this
93 option, you can totally disable graphical output so that QEMU is a
94 simple command line application. The emulated serial port is redi‐
95 rected on the console. Therefore, you can still use QEMU to debug a
96 Linux kernel with a serial console.
97 -vnc display
99 Normally, QEMU uses SDL to display the VGA output. With this
100 option, you can have QEMU listen on VNC display display and redi‐
101 rect the VGA display over the VNC session. It is very useful to
102 enable the usb tablet device when using this option (option -usbde‐
103 vice tablet). When using the VNC display, you must use the -k
104 option to set the keyboard layout if you are not using en-us.
105 display may be in the form interface:d, in which case connections
107 will only be allowed from interface on display d. Optionally,
108 interface can be omitted. display can also be in the form
109 unix:path where path is the location of a unix socket to listen for
110 connections on.
111 -k language
113 Use keyboard layout language (for example "fr" for French). This
114 option is only needed where it is not easy to get raw PC keycodes
115 (e.g. on Macs, with some X11 servers or with a VNC display). You
116 don't normally need to use it on PC/Linux or PC/Windows hosts.
117 The available layouts are:
119 ar de-ch es fo fr-ca hu ja mk no pt-br sv
121 da en-gb et fr fr-ch is lt nl pl ru th
122 de en-us fi fr-be hr it lv nl-be pt sl tr
123 The default is "en-us".
125 -audio-help
127 Will show the audio subsystem help: list of drivers, tunable param‐
128 eters.
129 -soundhw card1,card2,... or -soundhw all
131 Enable audio and selected sound hardware. Use ? to print all avail‐
132 able sound hardware.
133 qemu -soundhw sb16,adlib hda
135 qemu -soundhw es1370 hda
136 qemu -soundhw all hda
137 qemu -soundhw ?
138 -localtime
140 Set the real time clock to local time (the default is to UTC time).
141 This option is needed to have correct date in MS-DOS or Windows.
142 -full-screen
144 Start in full screen.
145 -pidfile file
147 Store the QEMU process PID in file. It is useful if you launch QEMU
148 from a script.
149 -daemonize
151 Daemonize the QEMU process after initialization. QEMU will not
152 detach from standard IO until it is ready to receive connections on
153 any of its devices. This option is a useful way for external pro‐
154 grams to launch QEMU without having to cope with initialization
155 race conditions.
156 -win2k-hack
158 Use it when installing Windows 2000 to avoid a disk full bug. After
159 Windows 2000 is installed, you no longer need this option (this
160 option slows down the IDE transfers).
161 -option-rom file
163 Load the contents of file as an option ROM. This option is useful
164 to load things like EtherBoot.
165 USB options:
167 -usb
169 Enable the USB driver (will be the default soon)
170 -usbdevice devname
172 Add the USB device devname.
173 Network options:
175 -net nic[,vlan=n][,macaddr=addr][,model=type]
177 Create a new Network Interface Card and connect it to VLAN n (n = 0
178 is the default). The NIC is currently an NE2000 on the PC target.
179 Optionally, the MAC address can be changed. If no -net option is
180 specified, a single NIC is created. Qemu can emulate several dif‐
181 ferent models of network card. Valid values for type are
182 "ne2k_pci", "ne2k_isa", "rtl8139", "smc91c111" and "lance". Not
183 all devices are supported on all targets.
184 -net user[,vlan=n][,hostname=name]
186 Use the user mode network stack which requires no administrator
187 priviledge to run. hostname=name can be used to specify the client
188 hostname reported by the builtin DHCP server.
189 -net tap[,vlan=n][,fd=h][,ifname=name][,script=file]
191 Connect the host TAP network interface name to VLAN n and use the
192 network script file to configure it. The default network script is
193 /etc/qemu-ifup. Use script=no to disable script execution. If name
194 is not provided, the OS automatically provides one. fd=h can be
195 used to specify the handle of an already opened host TAP interface.
196 Example:
197 qemu linux.img -net nic -net tap
199 More complicated example (two NICs, each one connected to a TAP
201 device)
202 qemu linux.img -net nic,vlan=0 -net tap,vlan=0,ifname=tap0 \
204 -net nic,vlan=1 -net tap,vlan=1,ifname=tap1
205 -net socket[,vlan=n][,fd=h][,listen=[host]:port][,connect=host:port]
207 Connect the VLAN n to a remote VLAN in another QEMU virtual machine
208 using a TCP socket connection. If listen is specified, QEMU waits
209 for incoming connections on port (host is optional). connect is
210 used to connect to another QEMU instance using the listen option.
211 fd=h specifies an already opened TCP socket.
212 Example:
214 # launch a first QEMU instance
216 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
217 -net socket,listen=:1234
218 # connect the VLAN 0 of this instance to the VLAN 0
219 # of the first instance
220 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
221 -net socket,connect=127.0.0.1:1234
222 -net socket[,vlan=n][,fd=h][,mcast=maddr:port]
224 Create a VLAN n shared with another QEMU virtual machines using a
225 UDP multicast socket, effectively making a bus for every QEMU with
226 same multicast address maddr and port. NOTES:
227 1. Several QEMU can be running on different hosts and share same
229 bus (assuming correct multicast setup for these hosts).
230 2. mcast support is compatible with User Mode Linux (argument
232 ethN=mcast), see <http://user-mode-linux.sf.net>.
233 3.<Use fd=h to specify an already opened UDP multicast socket.>
235 Example:
237 # launch one QEMU instance
239 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
240 -net socket,mcast=230.0.0.1:1234
241 # launch another QEMU instance on same "bus"
242 qemu linux.img -net nic,macaddr=52:54:00:12:34:57 \
243 -net socket,mcast=230.0.0.1:1234
244 # launch yet another QEMU instance on same "bus"
245 qemu linux.img -net nic,macaddr=52:54:00:12:34:58 \
246 -net socket,mcast=230.0.0.1:1234
247 Example (User Mode Linux compat.):
249 # launch QEMU instance (note mcast address selected
251 # is UML's default)
252 qemu linux.img -net nic,macaddr=52:54:00:12:34:56 \
253 -net socket,mcast=239.192.168.1:1102
254 # launch UML
255 /path/to/linux ubd0=/path/to/root_fs eth0=mcast
256 -net none
258 Indicate that no network devices should be configured. It is used
259 to override the default configuration (-net nic -net user) which is
260 activated if no -net options are provided.
261 -tftp prefix
263 When using the user mode network stack, activate a built-in TFTP
264 server. All filenames beginning with prefix can be downloaded from
265 the host to the guest using a TFTP client. The TFTP client on the
266 guest must be configured in binary mode (use the command "bin" of
267 the Unix TFTP client). The host IP address on the guest is as usual
268 10.0.2.2.
269 -smb dir
271 When using the user mode network stack, activate a built-in SMB
272 server so that Windows OSes can access to the host files in dir
273 transparently.
274 In the guest Windows OS, the line:
276 10.0.2.4 smbserver
278 must be added in the file C:\WINDOWS\LMHOSTS (for windows 9x/Me) or
280 C:\WINNT\SYSTEM32\DRIVERS\ETC\LMHOSTS (Windows NT/2000).
281 Then dir can be accessed in \\smbserver\qemu.
283 Note that a SAMBA server must be installed on the host OS in
285 /usr/sbin/smbd. QEMU was tested successfully with smbd version
286 2.2.7a from the Red Hat 9 and version 3.0.10-1.fc3 from Fedora Core
287 3.
288 -redir [tcp⎪udp]:host-port:[guest-host]:guest-port
290 When using the user mode network stack, redirect incoming TCP or
291 UDP connections to the host port host-port to the guest guest-host
292 on guest port guest-port. If guest-host is not specified, its value
293 is 10.0.2.15 (default address given by the built-in DHCP server).
294 For example, to redirect host X11 connection from screen 1 to guest
296 screen 0, use the following:
297 # on the host
299 qemu -redir tcp:6001::6000 [...]
300 # this host xterm should open in the guest X11 server
301 xterm -display :1
302 To redirect telnet connections from host port 5555 to telnet port
304 on the guest, use the following:
305 # on the host
307 qemu -redir tcp:5555::23 [...]
308 telnet localhost 5555
309 Then when you use on the host "telnet localhost 5555", you connect
311 to the guest telnet server.
312 Linux boot specific: When using these options, you can use a given
314 Linux kernel without installing it in the disk image. It can be useful
315 for easier testing of various kernels.
316 -kernel bzImage
318 Use bzImage as kernel image.
319 -append cmdline
321 Use cmdline as kernel command line
322 -initrd file
324 Use file as initial ram disk.
325 Debug/Expert options:
327 -serial dev
329 Redirect the virtual serial port to host character device dev. The
330 default device is "vc" in graphical mode and "stdio" in non graphi‐
331 cal mode.
332 This option can be used several times to simulate up to 4 serials
334 ports.
335 Use "-serial none" to disable all serial ports.
337 Available character devices are:
339 "vc"
341 Virtual console
342 "pty"
344 [Linux only] Pseudo TTY (a new PTY is automatically allocated)
345 "none"
347 No device is allocated.
348 "null"
350 void device
351 "/dev/XXX"
353 [Linux only] Use host tty, e.g. /dev/ttyS0. The host serial
354 port parameters are set according to the emulated ones.
355 "/dev/parportN"
357 [Linux only, parallel port only] Use host parallel port N. Cur‐
358 rently only SPP parallel port features can be used.
359 "file:filename"
361 Write output to filename. No character can be read.
362 "stdio"
364 [Unix only] standard input/output
365 "pipe:filename"
367 name pipe filename
368 "COMn"
370 [Windows only] Use host serial port n
371 "udp:[remote_host]:remote_port[@[src_ip]:src_port]"
373 This implements UDP Net Console. When remote_host or src_ip
374 are not specified they default to 0.0.0.0. When not using a
375 specifed src_port a random port is automatically chosen.
376 If you just want a simple readonly console you can use "netcat"
378 or "nc", by starting qemu with: "-serial udp::4555" and nc as:
379 "nc -u -l -p 4555". Any time qemu writes something to that port
380 it will appear in the netconsole session.
381 If you plan to send characters back via netconsole or you want
383 to stop and start qemu a lot of times, you should have qemu use
384 the same source port each time by using something like "-serial
385 udp::4555@4556" to qemu. Another approach is to use a patched
386 version of netcat which can listen to a TCP port and send and
387 receive characters via udp. If you have a patched version of
388 netcat which activates telnet remote echo and single char
389 transfer, then you can use the following options to step up a
390 netcat redirector to allow telnet on port 5555 to access the
391 qemu port.
392 "Qemu Options:"
394 -serial udp::4555@4556
395 "netcat options:"
397 -u -P 4555 -L 0.0.0.0:4556 -t -p 5555 -I -T
398 "telnet options:"
400 localhost 5555
401 "tcp:[host]:port[,server][,nowait][,nodelay]"
403 The TCP Net Console has two modes of operation. It can send
404 the serial I/O to a location or wait for a connection from a
405 location. By default the TCP Net Console is sent to host at
406 the port. If you use the server option QEMU will wait for a
407 client socket application to connect to the port before contin‐
408 uing, unless the "nowait" option was specified. The "nodelay"
409 option disables the Nagle buffering algoritm. If host is omit‐
410 ted, 0.0.0.0 is assumed. Only one TCP connection at a time is
411 accepted. You can use "telnet" to connect to the corresponding
412 character device.
413 "Example to send tcp console to 192.168.0.2 port 4444"
415 -serial tcp:192.168.0.2:4444
416 "Example to listen and wait on port 4444 for connection"
418 -serial tcp::4444,server
419 "Example to not wait and listen on ip 192.168.0.100 port 4444"
421 -serial tcp:192.168.0.100:4444,server,nowait
422 "telnet:host:port[,server][,nowait][,nodelay]"
424 The telnet protocol is used instead of raw tcp sockets. The
425 options work the same as if you had specified "-serial tcp".
426 The difference is that the port acts like a telnet server or
427 client using telnet option negotiation. This will also allow
428 you to send the MAGIC_SYSRQ sequence if you use a telnet that
429 supports sending the break sequence. Typically in unix telnet
430 you do it with Control-] and then type "send break" followed by
431 pressing the enter key.
432 "unix:path[,server][,nowait]"
434 A unix domain socket is used instead of a tcp socket. The
435 option works the same as if you had specified "-serial tcp"
436 except the unix domain socket path is used for connections.
437 -parallel dev
439 Redirect the virtual parallel port to host device dev (same devices
440 as the serial port). On Linux hosts, /dev/parportN can be used to
441 use hardware devices connected on the corresponding host parallel
442 port.
443 This option can be used several times to simulate up to 3 parallel
445 ports.
446 Use "-parallel none" to disable all parallel ports.
448 -monitor dev
450 Redirect the monitor to host device dev (same devices as the serial
451 port). The default device is "vc" in graphical mode and "stdio" in
452 non graphical mode.
453 -s Wait gdb connection to port 1234.
455 -p port
457 Change gdb connection port. port can be either a decimal number to
458 specify a TCP port, or a host device (same devices as the serial
459 port).
460 -S Do not start CPU at startup (you must type 'c' in the monitor).
462 -d Output log in /tmp/qemu.log
464 -hdachs c,h,s,[,t]
466 Force hard disk 0 physical geometry (1 <= c <= 16383, 1 <= h <= 16,
467 1 <= s <= 63) and optionally force the BIOS translation mode
468 (t=none, lba or auto). Usually QEMU can guess all thoses parame‐
469 ters. This option is useful for old MS-DOS disk images.
470 -L path
472 Set the directory for the BIOS, VGA BIOS and keymaps.
473 -std-vga
475 Simulate a standard VGA card with Bochs VBE extensions (default is
476 Cirrus Logic GD5446 PCI VGA). If your guest OS supports the VESA
477 2.0 VBE extensions (e.g. Windows XP) and if you want to use high
478 resolution modes (>= 1280x1024x16) then you should use this option.
479 -no-acpi
481 Disable ACPI (Advanced Configuration and Power Interface) support.
482 Use it if your guest OS complains about ACPI problems (PC target
483 machine only).
484 -no-reboot
486 Exit instead of rebooting.
487 -loadvm file
489 Start right away with a saved state ("loadvm" in monitor)
490 -semihosting
492 Enable "Angel" semihosting interface (ARM target machines only).
493 Note that this allows guest direct access to the host filesystem,
494 so should only be used with trusted guest OS.
495 During the graphical emulation, you can use the following keys:
497 Ctrl-Alt-f
499 Toggle full screen
500 Ctrl-Alt-n
502 Switch to virtual console 'n'. Standard console mappings are:
503 1 Target system display
505 2 Monitor
507 3 Serial port
509 Ctrl-Alt
511 Toggle mouse and keyboard grab.
512 In the virtual consoles, you can use Ctrl-Up, Ctrl-Down, Ctrl-PageUp
514 and Ctrl-PageDown to move in the back log.
515 During emulation, if you are using the -nographic option, use Ctrl-a h
517 to get terminal commands:
518 Ctrl-a h
520 Print this help
521 Ctrl-a x
523 Exit emulator
524 Ctrl-a s
526 Save disk data back to file (if -snapshot)
527 Ctrl-a b
529 Send break (magic sysrq in Linux)
530 Ctrl-a c
532 Switch between console and monitor
533 Ctrl-a Ctrl-a
535 Send Ctrl-a
536 The following options are specific to the PowerPC emulation:
538 -g WxH[xDEPTH]
540 Set the initial VGA graphic mode. The default is 800x600x15.
541 The following options are specific to the Sparc emulation:
543 -g WxH
545 Set the initial TCX graphic mode. The default is 1024x768.
546
548 The HTML documentation of QEMU for more precise information and Linux
549 user mode emulator invocation.
550
552 Fabrice Bellard
553 2008-02-27 QEMU(1)