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Spice aims to provide a complete open source solution for interaction with virtualized desktops


Current status

  • Last updated: 2013-05-07
  • Percentage of completion: 100%

Detailed Description

The Spice project deals with all of the infrastructure involved in connecting to and operating desktop environments remotely. It's main focus is on virtualized devices within qemu virtual machines, but it also provides a pure X frame buffer solution known as Xspice.

The Simple Protocol for Independent Computing Environments (SPICE) is used for client-server communication. Spice adds a QXL display device to QEMU and provides drivers for this device for both X and Windows. It also provides a Spice server and VDAgent to handle connections and transmit the information via the SPICE protocol to clients. The Spice project provides a Linux, Windows, and HTML5 client. There are experimental Mac OS X and Android clients as well.

Features supported in the protocol are:

  • Accelerated 2D graphics
  • "Hardware" cursor support
  • Audio playing
  • Audio recording
  • Image compression, both lossless and lossy (for WAN support)
  • Video detection with MJpeg streaming
  • Encryption
  • Client side mouse pointer support
  • Drivers for: X, Windows (xp, vista, win7)

Red Hat acquired Spice together with kvm when it aqcuired Qumranet, and has invested significant effort into opening it up, cleaning up dependencies, etc.

Benefit to Fedora

In the long term, Spice will let Fedora provide a better user experience in desktop virtualization. In the short term, Fedora gains an interesting new open-source technology that many people want to try out.


Other (non-mandatory) spice-related bits useful to have in Fedora:

  • gdm does not supply xdmcp any longer [[1]]

This would be useful for creating an Xspice server to generate session logins

  • Return of pipe sink modules for sound for Xspice [[2]]

A common use for spice is to run windows client, and spice ships with several windows parts:

  • A video driver.
  • An agent for doing operations inside the guest.
  • virtio serial driver for talking to the agent.

It might be interesting to package these in fedora somehow so that its easy to deploy them. Note that the fedora package guidelines don't allow shipping pre-compiled blobs. Which implies we must build the windows binaries in mock/koji. Which implies we must be able to cross-build all bits using the mingw compiler.

How To Test


The server part of Spice requires a x86-64 machine, and ideally should have hardware virtualization support (kvm) although this is not strictly required.

The client currently works on x86-64 and x86, but we're working on porting it to more architectures.

You will need a host system, guest system, and client system. The host system runs qemu to launch the guest VM. You connect from the client system to view the guest VM. Often, the client system is the same as the host system, at least for simple testing.

To test spice, install a qemu with spice support and spice-server on the host machine, then start qemu with options something like this:

 qemu <disk-image> -usbdevice tablet -soundhw ac97 -vga qxl -spice port=5930,disable-ticketing -enable-kvm

or with passwords:

 qemu <disk-image> -usbdevice tablet -soundhw ac97 -vga qxl -spice port=5930,password=<secret> -enable-kvm

In the guest, you will need to install xorg-x11-drv-qxl and you will want to install spice-vdagent.

On the client, you will need a spice client. Modern use suggests that you use remote-viewer, which requires the virt-viewer and spice-gtk3 packages on Fedora. (Old clients include spice-client, which provides spicec, and spice-gtk-tools, which provides spicy).

To run, invoke as follows:

 remote-viewer spice://localhost:1234

This should let you access the machine.


Xspice creates a virtual X server that you can then connect to remotely using any Spice client. To use, you will need the xorg-x11-server-Xspice package installed.

Start an X server as follows:

 Xspice --disable-ticketing --xsession /usr/bin/gnome-terminal :1 --port 1234 &

Then connect with any spice client (see the remote-viewer section, above), and you should see a simple X server with a gnome-terminal.

Nicer session
Of course, a gnome terminal isn't all that pretty. Unfortunately, running a full gnome-session is tricky, because it will conflict with your current running session. If you put the following lines:
eval `dbus-launch --sh-syntax –exit-with-session`
exec  gnome-session
in an executable bash script and pass that script to --xsession, you'll get a full Gnome session. You may have to do further tweaking to get applications like Firefox to run well also.
XDMCP support
XDMCP, in theory, would let you run an Xspice session that would allow anyone to log in to a new session. Simply passing '-query <hostname-running-XDMCP>' instead of the '--xsession /usr/bin/gnome-terminal' should accomplish this. Unfortunately, gdm does not currently support this, due to bug 690926. You can install xdm to accomplish this result instead.


Spice provides a pure HTML5 client option. To use this, you will need to have the spice-html5 and python-websockify packages installed. Then, start a Spice server as you normally would (see either the Xspice or QEMU sections, above).

  • Install the Apache configuration file
 sudo cp /usr/share/doc/spice-html5*/apache.conf.sample /etc/httpd/conf.d/spice.conf
 sudo systemctl restart httpd
  • Start websockify, providing a new port, and the host and port where the Spice server is running.
 websockify 5959 localhost:5900
  • Open a web browser, and navigate to http://<system-with-apache>/spice/

Enter the address of the system running websockify, and the port (e.g. 5959) you specified when you invoked websockify, and click 'Start'. You should now see your Spice session.

User Experience


  • qemu


Note that most of the official documentation is generally badly out of date.

Release Notes

  • Fedora 14 introduces the Spice framework for desktop virtualization.

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