man qemu Command

Man page for apt-get qemu Command

Man Page for qemu in Linux

Ubuntu Man Command : man qemu

Man Qemu  Command

This tutorial shows the man page for man qemu in linux.

Open terminal with 'su' access and type the command as shown below:
man qemu

Result of the Command Execution shown below:

QEMU(1)                                                                QEMU(1)

qemu doc QEMU Emulator User Documentation

usage: qemu [options] [disk_image]

The QEMU PC System emulator simulates the following peripherals:

i440FX host PCI bridge and PIIX3 PCI to ISA bridge

Cirrus CLGD 5446 PCI VGA card or dummy VGA card with Bochs VESA
extensions (hardware level, including all non standard modes).

PS/2 mouse and keyboard

2 PCI IDE interfaces with hard disk and CD ROM support

Floppy disk

PCI and ISA network adapters

Serial ports

Creative SoundBlaster 16 sound card

ENSONIQ AudioPCI ES1370 sound card

Intel 82801AA AC97 Audio compatible sound card

Adlib(OPL2) Yamaha YM3812 compatible chip

Gravis Ultrasound GF1 sound card

CS4231A compatible sound card

PCI UHCI USB controller and a virtual USB hub.

SMP is supported with up to 255 CPUs.

Note that adlib, gus and cs4231a are only available when QEMU was
configured with audio card list option containing the name(s) of
required card(s).

QEMU uses the PC BIOS from the Bochs project and the Plex86/Bochs LGPL

QEMU uses YM3812 emulation by Tatsuyuki Satoh.

QEMU uses GUS emulation(GUSEMU32 )
by Tibor "TS" SchA~Xtz.

Not that, by default, GUS shares IRQ(7) with parallel ports and so qemu
must be told to not have parallel ports to have working GUS

qemu dos.img soundhw gus parallel none


qemu dos.img device gus,irq=5

Or some other unclaimed IRQ.

CS4231A is the chip used in Windows Sound System and GUSMAX products

disk_image is a raw hard disk image for IDE hard disk 0. Some targets
do not need a disk image.

Standard options:

h Display help and exit

Display version information and exit

M machine
Select the emulated machine (" M ?" for list)

cpu model
Select CPU model ( cpu ? for list and additional feature selection)

Simulate an SMP system with n CPUs. On the PC target, up to 255
CPUs are supported. On Sparc32 target, Linux limits the number of
usable CPUs to 4. For the PC target, the number of cores per
socket, the number of threads per cores and the total number of
sockets can be specified. Missing values will be computed. If any
on the three values is given, the total number of CPUs n can be
omitted. maxcpus specifies the maximum number of hotpluggable CPUs.

numa opts
Simulate a multi node NUMA system. If mem and cpus are omitted,
resources are split equally.

fda file
fdb file
Use file as floppy disk 0/1 image. You can use the host floppy by
using /dev/fd0 as filename.

hda file
hdb file
hdc file
hdd file
Use file as hard disk 0, 1, 2 or 3 image.

cdrom file
Use file as CD ROM image (you cannot use hdc and cdrom at the
same time). You can use the host CD ROM by using /dev/cdrom as

drive option[,option[,option[,...]]]
Define a new drive. Valid options are:

This option defines which disk image to use with this drive. If
the filename contains comma, you must double it (for instance,
"file=my,,file" to use file "my,file").

This option defines on which type on interface the drive is
connected. Available types are: ide, scsi, sd, mtd, floppy,
pflash, virtio.

These options define where is connected the drive by defining
the bus number and the unit id.

This option defines where is connected the drive by using an
index in the list of available connectors of a given interface

This option defines the type of the media: disk or cdrom.

These options have the same definition as they have in hdachs.

snapshot is "on" or "off" and allows to enable snapshot for
given drive (see snapshot).

cache is "none", "writeback", or "writethrough" and controls
how the host cache is used to access block data.

aio is "threads", or "native" and selects between pthread based
disk I/O and native Linux AIO.

Specify which disk format will be used rather than detecting
the format. Can be used to specifiy format=raw to avoid
interpreting an untrusted format header.

This option specifies the serial number to assign to the

Specify the controller's PCI address (if=virtio only).

By default, writethrough caching is used for all block device.
This means that the host page cache will be used to read and write
data but write notification will be sent to the guest only when the
data has been reported as written by the storage subsystem.

Writeback caching will report data writes as completed as soon as
the data is present in the host page cache. This is safe as long
as you trust your host. If your host crashes or loses power, then
the guest may experience data corruption. When using the snapshot
option, writeback caching is used by default.

The host page cache can be avoided entirely with cache=none. This
will attempt to do disk IO directly to the guests memory. QEMU may
still perform an internal copy of the data.

Some block drivers perform badly with cache=writethrough, most
notably, qcow2. If performance is more important than correctness,
cache=writeback should be used with qcow2.

Instead of cdrom you can use:

qemu drive file=file,index=2,media=cdrom

Instead of hda, hdb, hdc, hdd, you can use:

qemu drive file=file,index=0,media=disk
qemu drive file=file,index=1,media=disk
qemu drive file=file,index=2,media=disk
qemu drive file=file,index=3,media=disk

You can connect a CDROM to the slave of ide0:

qemu drive file=file,if=ide,index=1,media=cdrom

If you don't specify the "file=" argument, you define an empty

qemu drive if=ide,index=1,media=cdrom

You can connect a SCSI disk with unit ID 6 on the bus

Related Topics

Apt Get Commands