user_Introduction.xml revision 33114510395fbb4bcbbe93108c897e6b8b2cd7bc
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febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>VirtualBox is a cross-platform virtualization application. What does
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync that mean? For one thing, it installs on your existing Intel or AMD-based
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync computers, whether they are running Windows, Mac, Linux or Solaris operating
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync systems. Secondly, it extends the capabilities of your existing computer so
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync that it can run multiple operating systems (inside multiple virtual
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync machines) at the same time. So, for example, you can run Windows and Linux
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync on your Mac, run Windows Server 2008 on your Linux server, run Linux on your
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Windows PC, and so on, all alongside your existing applications. You can
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync install and run as many virtual machines as you like -- the only practical
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync limits are disk space and memory.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>VirtualBox is deceptively simple yet also very powerful. It can run
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync everywhere from small embedded systems or desktop class machines all the way
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync up to datacenter deployments and even Cloud environments.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The following screenshot shows you how VirtualBox, installed on a Mac
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync computer, is running Windows 7 in a virtual machine window:</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imagedata align="center" fileref="images/vm-vista-running.png"
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync width="14cm" />
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>In this User Manual, we'll begin simply with a quick introduction to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync virtualization and how to get your first virtual machine running with the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync easy-to-use VirtualBox graphical user interface. Subsequent chapters will go
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync into much more detail covering more powerful tools and features, but
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync fortunately, it is not necessary to read the entire User Manual before you
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync can use VirtualBox.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>You can find a summary of VirtualBox's capabilities in <xref
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync linkend="features-overview" />. For existing VirtualBox users who just want
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync to see what's new in this release, there is a detailed list in <xref
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The techniques and features that VirtualBox provides are useful for
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync several scenarios:</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Running multiple operating systems
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync simultaneously.</emphasis> VirtualBox allows you to run more than one
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync operating system at a time. This way, you can run software written for
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync one operating system on another (for example, Windows software on
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Linux or a Mac) without having to reboot to use it. Since you can
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync configure what kinds of "virtual" hardware should be presented to each
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync such operating system, you can install an old operating system such as
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync DOS or OS/2 even if your real computer's hardware is no longer
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync supported by that operating system.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Easier software installations.</emphasis>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Software vendors can use virtual machines to ship entire software
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync configurations. For example, installing a complete mail server
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync solution on a real machine can be a tedious task. With VirtualBox,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync such a complex setup (then often called an "appliance") can be packed
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync into a virtual machine. Installing and running a mail server becomes
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync as easy as importing such an appliance into VirtualBox.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Testing and disaster recovery.</emphasis>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Once installed, a virtual machine and its virtual hard disks can be
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync considered a "container" that can be arbitrarily frozen, woken up,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync copied, backed up, and transported between hosts.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>On top of that, with the use of another VirtualBox feature
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync called "snapshots", one can save a particular state of a virtual
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync machine and revert back to that state, if necessary. This way, one can
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync freely experiment with a computing environment. If something goes
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync wrong (e.g. after installing misbehaving software or infecting the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync guest with a virus), one can easily switch back to a previous snapshot
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync and avoid the need of frequent backups and restores.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Any number of snapshots can be created, allowing you to travel
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync back and forward in virtual machine time. You can delete snapshots
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync while a VM is running to reclaim disk space.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Infrastructure consolidation.</emphasis>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Virtualization can significantly reduce hardware and electricity
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync costs. Most of the time, computers today only use a fraction of their
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync potential power and run with low average system loads. A lot of
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync hardware resources as well as electricity is thereby wasted. So,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync instead of running many such physical computers that are only
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync partially used, one can pack many virtual machines onto a few powerful
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync hosts and balance the loads between them.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </itemizedlist>
64863d3a0ffadf1ac248b295b78be5d55db6ee13vboxsync <para>When dealing with virtualization (and also for understanding the
64863d3a0ffadf1ac248b295b78be5d55db6ee13vboxsync following chapters of this documentation), it helps to acquaint oneself
e7c4c205cb0af88b5ef0786be46da94847a9a37bvboxsync with a bit of crucial terminology, especially the following terms:</para>
64863d3a0ffadf1ac248b295b78be5d55db6ee13vboxsync <glosslist>
64863d3a0ffadf1ac248b295b78be5d55db6ee13vboxsync <glossentry>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <glossterm>Host operating system (host OS).</glossterm>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>This is the operating system of the physical computer on which
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox was installed. There are versions of VirtualBox for
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Windows, Mac OS X, Linux and Solaris hosts; for details, please see
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Most of the time, this User Manual discusses all VirtualBox
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync versions together. There may be platform-specific differences which
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync we will point out where appropriate.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </glossdef>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </glossentry>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <glossentry>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <glossterm>Guest operating system (guest OS).</glossterm>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>This is the operating system that is running inside the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync virtual machine. Theoretically, VirtualBox can run any x86 operating
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync system (DOS, Windows, OS/2, FreeBSD, OpenBSD), but to achieve
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync near-native performance of the guest code on your machine, we had to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync go through a lot of optimizations that are specific to certain
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync operating systems. So while your favorite operating system
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <emphasis>may</emphasis> run as a guest, we officially support and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync optimize for a select few (which, however, include the most common
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync ones).</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>See <xref linkend="guestossupport" /> for details.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </glossdef>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </glossentry>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <glossentry>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>This is the special environment that VirtualBox creates for
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync your guest operating system while it is running. In other words, you
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync run your guest operating system "in" a VM. Normally, a VM will be
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync shown as a window on your computer's desktop, but depending on which
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync of the various frontends of VirtualBox you use, it can be displayed
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync in full screen mode or remotely on another computer.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>In a more abstract way, internally, VirtualBox thinks of a VM
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync as a set of parameters that determine its behavior. They include
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync hardware settings (how much memory the VM should have, what hard
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync disks VirtualBox should virtualize through which container files,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync what CDs are mounted etc.) as well as state information (whether the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VM is currently running, saved, its snapshots etc.). These settings
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync are mirrored in the VirtualBox Manager window as well as the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <computeroutput>VBoxManage</computeroutput> command line program;
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync see <xref linkend="vboxmanage" />. In other words, a VM is also what
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync you can see in its settings dialog.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </glossdef>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </glossentry>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <glossentry>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>This refers to special software packages which are shipped
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync with VirtualBox but designed to be installed
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <emphasis>inside</emphasis> a VM to improve performance of the guest
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync OS and to add extra features. This is described in detail in <xref
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </glossdef>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </glossentry>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </glosslist>
241adddf415cbdf66230864a215b24415f482e72vboxsync <para>Here's a brief outline of VirtualBox's main features:</para>
241adddf415cbdf66230864a215b24415f482e72vboxsync <itemizedlist>
241adddf415cbdf66230864a215b24415f482e72vboxsync <para><emphasis role="bold">Portability.</emphasis> VirtualBox runs on
241adddf415cbdf66230864a215b24415f482e72vboxsync a large number of 32-bit and 64-bit host operating systems (again, see
241adddf415cbdf66230864a215b24415f482e72vboxsync <xref linkend="hostossupport" /> for details).</para>
241adddf415cbdf66230864a215b24415f482e72vboxsync <para>VirtualBox is a so-called "hosted" hypervisor (sometimes
241adddf415cbdf66230864a215b24415f482e72vboxsync referred to as a "type 2" hypervisor). Whereas a "bare-metal" or "type
241adddf415cbdf66230864a215b24415f482e72vboxsync 1" hypervisor would run directly on the hardware, VirtualBox requires
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync an existing operating system to be installed. It can thus run
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync alongside existing applications on that host.</para>
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync <para>To a very large degree, VirtualBox is functionally identical on
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync all of the host platforms, and the same file and image formats are
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync used. This allows you to run virtual machines created on one host on
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync another host with a different host operating system; for example, you
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync can create a virtual machine on Windows and then run it under
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Linux.</para>
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync <para>In addition, virtual machines can easily be imported and
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync exported using the Open Virtualization Format (OVF, see <xref
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync linkend="ovf" />), an industry standard created for this purpose. You
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync can even import OVFs that were created with a different virtualization
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync software.</para>
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync </listitem>
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync <para><emphasis role="bold">No hardware virtualization
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync required.</emphasis> For many scenarios, VirtualBox does not require
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the processor features built into newer hardware like Intel VT-x or
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync AMD-V. As opposed to many other virtualization solutions, you can
241adddf415cbdf66230864a215b24415f482e72vboxsync therefore use VirtualBox even on older hardware where these features
241adddf415cbdf66230864a215b24415f482e72vboxsync are not present. The technical details are explained in <xref
241adddf415cbdf66230864a215b24415f482e72vboxsync </listitem>
241adddf415cbdf66230864a215b24415f482e72vboxsync <para><emphasis role="bold">Guest Additions: shared folders, seamless
241adddf415cbdf66230864a215b24415f482e72vboxsync windows, 3D virtualization.</emphasis> The VirtualBox Guest Additions
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync are software packages which can be installed
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <emphasis>inside</emphasis> of supported guest systems to improve
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync their performance and to provide additional integration and
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync communication with the host system. After installing the Guest
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync Additions, a virtual machine will support automatic adjustment of
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync video resolutions, seamless windows, accelerated 3D graphics and more.
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync The Guest Additions are described in detail in <xref
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync <para>In particular, Guest Additions provide for "shared folders",
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync which let you access files from the host system from within a guest
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync machine. Shared folders are described in <xref
a8ce9568e18b8c1a49833bf3b3ac2b2cc634b13cvboxsync </listitem>
241adddf415cbdf66230864a215b24415f482e72vboxsync <para><emphasis role="bold">Great hardware support.</emphasis> Among
241adddf415cbdf66230864a215b24415f482e72vboxsync others, VirtualBox supports:</para>
241adddf415cbdf66230864a215b24415f482e72vboxsync <itemizedlist>
241adddf415cbdf66230864a215b24415f482e72vboxsync (SMP).</emphasis> VirtualBox can present up to 32 virtual CPUs to
241adddf415cbdf66230864a215b24415f482e72vboxsync each virtual machine, irrespective of how many CPU cores are
241adddf415cbdf66230864a215b24415f482e72vboxsync physically present on your host.</para>
241adddf415cbdf66230864a215b24415f482e72vboxsync </listitem>
241adddf415cbdf66230864a215b24415f482e72vboxsync <para><emphasis role="bold">USB device support.</emphasis>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox implements a virtual USB controller and allows you to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync connect arbitrary USB devices to your virtual machines without
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync having to install device-specific drivers on the host. USB support
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync is not limited to certain device categories. For details, see
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Hardware compatibility.</emphasis>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox virtualizes a vast array of virtual devices, among them
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync many devices that are typically provided by other virtualization
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync platforms. That includes IDE, SCSI and SATA hard disk controllers,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync several virtual network cards and sound cards, virtual serial and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync parallel ports and an Input/Output Advanced Programmable Interrupt
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Controller (I/O APIC), which is found in many modern PC systems.
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync This eases cloning of PC images from real machines and importing
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync of third-party virtual machines into VirtualBox.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Full ACPI support.</emphasis> The
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Advanced Configuration and Power Interface (ACPI) is fully
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync supported by VirtualBox. This eases cloning of PC images from real
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync machines or third-party virtual machines into VirtualBox. With its
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync unique <emphasis role="bold">ACPI power status support,</emphasis>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox can even report to ACPI-aware guest operating systems
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the power status of the host. For mobile systems running on
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync battery, the guest can thus enable energy saving and notify the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync user of the remaining power (e.g. in full screen modes).</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Multiscreen resolutions.</emphasis>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox virtual machines support screen resolutions many times
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync that of a physical screen, allowing them to be spread over a large
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync number of screens attached to the host system.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Built-in iSCSI support.</emphasis>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync This unique feature allows you to connect a virtual machine
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync directly to an iSCSI storage server without going through the host
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync system. The VM accesses the iSCSI target directly without the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync extra overhead that is required for virtualizing hard disks in
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync container files. For details, see <xref
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">PXE Network boot.</emphasis> The
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync integrated virtual network cards of VirtualBox fully support
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync remote booting via the Preboot Execution Environment (PXE).</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Multigeneration branched
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync snapshots.</emphasis> VirtualBox can save arbitrary snapshots of the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync state of the virtual machine. You can go back in time and revert the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync virtual machine to any such snapshot and start an alternative VM
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync configuration from there, effectively creating a whole snapshot tree.
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync For details, see <xref linkend="snapshots" />. You can create and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync delete snapshots while the virtual machine is running.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Clean architecture; unprecedented
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync modularity.</emphasis> VirtualBox has an extremely modular design with
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync well-defined internal programming interfaces and a clean separation of
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync client and server code. This makes it easy to control it from several
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync interfaces at once: for example, you can start a VM simply by clicking
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync on a button in the VirtualBox graphical user interface and then
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync control that machine from the command line, or even remotely. See
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Due to its modular architecture, VirtualBox can also expose its
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync full functionality and configurability through a comprehensive
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <emphasis role="bold">software development kit (SDK),</emphasis> which
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync allows for integrating every aspect of VirtualBox with other software
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync systems. Please see <xref linkend="VirtualBoxAPI" /> for
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync details.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Remote machine display.</emphasis> The
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox Remote Desktop Extension (VRDE) allows for high-performance
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync remote access to any running virtual machine. This extension supports
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the Remote Desktop Protocol (RDP) originally built into Microsoft
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Windows, with special additions for full client USB support.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The VRDE does not rely on the RDP server that is built into
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Microsoft Windows; instead, it is plugged directly into the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync virtualization layer. As a result, it works with guest operating
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync systems other than Windows (even in text mode) and does not require
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync application support in the virtual machine either. The VRDE is
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync described in detail in <xref linkend="vrde" />.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>On top of this special capacity, VirtualBox offers you more
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync unique features:<itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync authentication.</emphasis> VirtualBox already supports Winlogon
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync on Windows and PAM on Linux for RDP authentication. In addition,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync it includes an easy-to-use SDK which allows you to create
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync arbitrary interfaces for other methods of authentication; see
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">USB over RDP.</emphasis> Via RDP
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync virtual channel support, VirtualBox also allows you to connect
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync arbitrary USB devices locally to a virtual machine which is
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync running remotely on a VirtualBox RDP server; see <xref
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <title id="hostossupport">Supported host operating systems</title>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Currently, VirtualBox runs on the following host operating
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync systems:</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Windows</emphasis> hosts:<itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Windows XP, all service packs (32-bit)</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Support for 64-bit Windows was added with VirtualBox
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync 1.5.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Windows Server 2008 (32-bit and 64-bit)</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Mac OS X</emphasis> hosts:<footnote>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Preliminary Mac OS X support (beta stage) was added with
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox 1.4, full support with 1.6. Mac OS X 10.4 (Tiger)
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync support was removed with VirtualBox 3.1.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>10.6 (Snow Leopard, 32-bit and 64-bit)</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Linux</emphasis> hosts (32-bit and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync 64-bit<footnote>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Support for 64-bit Linux was added with VirtualBox
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync 1.4.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </footnote>). Among others, this includes:<itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>8.04 ("Hardy Heron"),
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync 8.10 ("Intrepid Ibex"), 9.04 ("Jaunty Jackalope"), 9.10 ("Karmic
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Koala"), 10.04 ("Lucid Lynx"), 10.10 ("Maverick Meerkat),
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync 11.04 ("Natty Narwhal"), 11.10 ("Oneiric Oncelot"),
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync 12.04 ("Precise Pangolin")</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Debian GNU/Linux 5.0 ("lenny") and 6.0 ("squeeze")</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Oracle Enterprise Linux 4 and 5, Oracle Linux 6</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>openSUSE 11.0, 11.1, 11.2, 11.3, 11.4, 12.1, 12.2</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>It should be possible to use VirtualBox on most systems based on
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Linux kernel 2.6 using either the VirtualBox installer or by doing a
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync manual installation; see <xref linkend="install-linux-host" />. However,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the formally tested and supported Linux distributions are those for
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync which we offer a dedicated package.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Note that starting with VirtualBox 2.1, Linux 2.4-based host
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync operating systems are no longer supported.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Solaris</emphasis> hosts (32-bit and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync 64-bit) are supported with the restrictions listed in <xref
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Solaris 11 including Solaris 11 Express</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
fd60bfdb327b9b1e7a6d084cf368fb7f07c566cfvboxsync </listitem>
223935479ac42db56b7b7a7d16548d590022996avboxsync </listitem>
223935479ac42db56b7b7a7d16548d590022996avboxsync </itemizedlist>
223935479ac42db56b7b7a7d16548d590022996avboxsync <para>Note that the above list is informal. Oracle support for customers
fd60bfdb327b9b1e7a6d084cf368fb7f07c566cfvboxsync who have a support contract is limited to a subset of the listed host
fd60bfdb327b9b1e7a6d084cf368fb7f07c566cfvboxsync operating systems. Also, any feature which is marked as <emphasis
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync role="bold">experimental</emphasis> is not supported. Feedback and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync suggestions about such features are welcome.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <title>Installing VirtualBox and extension packs</title>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>VirtualBox comes in many different packages, and installation
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync depends on your host operating system. If you have installed software
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync before, installation should be straightforward: on each host platform,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox uses the installation method that is most common and easy to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync use. If you run into trouble or have special requirements, please refer to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <xref linkend="installation" /> for details about the various installation
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync methods.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Starting with version 4.0, VirtualBox is split into several
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync components.<orderedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The base package consists of all open-source components and is
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync licensed under the GNU General Public License V2.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
64863d3a0ffadf1ac248b295b78be5d55db6ee13vboxsync <para>Additional extension packs can be downloaded which extend the
64863d3a0ffadf1ac248b295b78be5d55db6ee13vboxsync functionality of the VirtualBox base package. Currently, Oracle
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync provides the one extension pack, which can be found at <ulink
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync url="http://www.virtualbox.org">http://www.virtualbox.org</ulink>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync and provides the following added functionality:<orderedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>VirtualBox Remote Desktop Protocol (VRDP) support; see
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Intel PXE boot ROM with support for the E1000 network
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync card.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Experimental support for PCI passthrough on Linux hosts;
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>VirtualBox extension packages have a
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <computeroutput>.vbox-extpack</computeroutput> file name extension.
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync To install an extension, simply double-click on the package file,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync and the VirtualBox Manager will guide you through the required
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync steps.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>To view the extension packs that are currently installed,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync please start the VirtualBox Manager (see the next section). From the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync "File" menu, please select "Preferences". In the window that shows
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync up, go to the "Extensions" category which shows you the extensions
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync which are currently installed and allows you to remove a package or
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync add a new one.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Alternatively you can use VBoxManage on the command line: see
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <xref linkend="vboxmanage-extpack" /> for details.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>After installation, you can start VirtualBox as
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync follows:<itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>On a Windows host, in the standard "Programs" menu, click on
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the item in the "VirtualBox" group. On Vista or Windows 7, you can
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync also type "VirtualBox" in the search box of the "Start" menu.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>On a Mac OS X host, in the Finder, double-click on the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync "VirtualBox" item in the "Applications" folder. (You may want to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync drag this item onto your Dock.)</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>On a Linux or Solaris host, depending on your desktop
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync environment, a "VirtualBox" item may have been placed in either the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync "System" or "System Tools" group of your "Applications" menu.
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Alternatively, you can type
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <computeroutput>VirtualBox</computeroutput> in a terminal.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>When you start VirtualBox for the first time, a window like the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync following should come up:</para>
574d36adfdd4d9e62af3640ecde108bdefb1c663vboxsync <imageobject>
574d36adfdd4d9e62af3640ecde108bdefb1c663vboxsync <imagedata align="center" fileref="images/virtualbox-main-empty.png"
574d36adfdd4d9e62af3640ecde108bdefb1c663vboxsync width="10cm" />
574d36adfdd4d9e62af3640ecde108bdefb1c663vboxsync </imageobject>
574d36adfdd4d9e62af3640ecde108bdefb1c663vboxsync role="bold">"VirtualBox Manager".</emphasis> On the left, you can see a
574d36adfdd4d9e62af3640ecde108bdefb1c663vboxsync pane that will later list all your virtual machines. Since you have not
574d36adfdd4d9e62af3640ecde108bdefb1c663vboxsync created any, the list is empty. A row of buttons above it allows you to
574d36adfdd4d9e62af3640ecde108bdefb1c663vboxsync create new VMs and work on existing VMs, once you have some. The pane on
574d36adfdd4d9e62af3640ecde108bdefb1c663vboxsync the right displays the properties of the virtual machine currently
574d36adfdd4d9e62af3640ecde108bdefb1c663vboxsync selected, if any. Again, since you don't have any machines yet, the pane
574d36adfdd4d9e62af3640ecde108bdefb1c663vboxsync displays a welcome message.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>To give you an idea what VirtualBox might look like later, after you
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync have created many machines, here's another example:</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imagedata align="center" fileref="images/virtualbox-main.png"
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync width="10cm" />
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Click on the "New" button at the top of the VirtualBox Manager
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync window. A wizard will pop up to guide you through setting up a new virtual
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync machine (VM):</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imagedata align="center" fileref="images/create-vm-1.png"
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync width="10cm" />
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </mediaobject>On the following pages, the wizard will ask you for the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync bare minimum of information that is needed to create a VM, in
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync particular:<orderedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The <emphasis role="bold">VM name</emphasis> will later be
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync shown in the VM list of the VirtualBox Manager window, and it will
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync be used for the VM's files on disk. Even though any name could be
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync used, keep in mind that once you have created a few VMs, you will
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync appreciate if you have given your VMs rather informative names; "My
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VM" would thus be less useful than "Windows XP SP2 with
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync OpenOffice".</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>For <emphasis role="bold">"Operating System Type",</emphasis>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync select the operating system that you want to install later. The
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync supported operating systems are grouped; if you want to install
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync something very unusual that is not listed, select "Other". Depending
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync on your selection, VirtualBox will enable or disable certain VM
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync settings that your guest operating system may require. This is
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync particularly important for 64-bit guests (see <xref
447cbf113f44132911fc13dc33cb26603759b82evboxsync linkend="intro-64bitguests" />). It is therefore recommended to
447cbf113f44132911fc13dc33cb26603759b82evboxsync always set it to the correct value.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>On the next page, select the <emphasis role="bold">memory
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync (RAM)</emphasis> that VirtualBox should allocate every time the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync virtual machine is started. The amount of memory given here will be
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync taken away from your host machine and presented to the guest
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync operating system, which will report this size as the (virtual)
447cbf113f44132911fc13dc33cb26603759b82evboxsync computer's installed RAM.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Choose this setting carefully! The memory you give to the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VM will not be available to your host OS while the VM is
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync running, so do not specify more than you can spare. For example,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync if your host machine has 1 GB of RAM and you enter 512 MB as the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync amount of RAM for a particular virtual machine, while that VM is
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync running, you will only have 512 MB left for all the other
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync software on your host. If you run two VMs at the same time, even
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync more memory will be allocated for the second VM (which may not
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync even be able to start if that memory is not available). On the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync other hand, you should specify as much as your guest OS (and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync your applications) will require to run properly.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>A Windows XP guest will require at least a few hundred MB RAM
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync to run properly, and Windows Vista will even refuse to install with
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync less than 512 MB. Of course, if you want to run graphics-intensive
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync applications in your VM, you may require even more RAM.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>So, as a rule of thumb, if you have 1 GB of RAM or more in
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync your host computer, it is usually safe to allocate 512 MB to each
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VM. But, in any case, make sure you always have at least 256 to 512
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync MB of RAM left on your host operating system. Otherwise you may
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync cause your host OS to excessively swap out memory to your hard disk,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync effectively bringing your host system to a standstill.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>As with the other settings, you can change this setting later,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync after you have created the VM.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Next, you must specify a <emphasis role="bold">virtual hard
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>There are many and potentially complicated ways in which
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox can provide hard disk space to a VM (see <xref
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync linkend="storage" /> for details), but the most common way is to use
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync a large image file on your "real" hard disk, whose contents
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox presents to your VM as if it were a complete hard disk.
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync This file represents an entire hard disk then, so you can even copy
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync it to another host and use it with another VirtualBox
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync installation.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The wizard shows you the following window:</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imagedata align="center" fileref="images/create-vm-2.png"
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync width="10cm" />
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>To create a new, empty virtual hard disk, press the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <emphasis role="bold">"New"</emphasis> button.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync role="bold">existing</emphasis> disk image file.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The <emphasis role="bold">drop-down list</emphasis>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync presented in the window contains all disk images which are
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync currently remembered by VirtualBox, probably because they are
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync currently attached to a virtual machine (or have been in the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync past).</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Alternatively, you can click on the small <emphasis
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync role="bold">folder button</emphasis> next to the drop-down
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync list to bring up a standard file dialog, which allows you to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync pick any disk image file on your host disk.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
447cbf113f44132911fc13dc33cb26603759b82evboxsync </itemizedlist>Most probably, if you are using VirtualBox for the
4fac78486305f1f002adbf23953382e5d832af94vboxsync first time, you will want to create a new disk image. Hence, press
447cbf113f44132911fc13dc33cb26603759b82evboxsync the "New" button.</para>
447cbf113f44132911fc13dc33cb26603759b82evboxsync role="bold">"Create New Virtual Disk Wizard",</emphasis> which helps
447cbf113f44132911fc13dc33cb26603759b82evboxsync you create a new disk image file in the new virtual machine's
447cbf113f44132911fc13dc33cb26603759b82evboxsync folder.</para>
447cbf113f44132911fc13dc33cb26603759b82evboxsync <para>VirtualBox supports two types of image files:<itemizedlist>
447cbf113f44132911fc13dc33cb26603759b82evboxsync <para>A <emphasis role="bold">dynamically allocated
447cbf113f44132911fc13dc33cb26603759b82evboxsync file</emphasis> will only grow in size when the guest actually
447cbf113f44132911fc13dc33cb26603759b82evboxsync stores data on its virtual hard disk. It will therefore
447cbf113f44132911fc13dc33cb26603759b82evboxsync initially be small on the host hard drive and only later grow
4fac78486305f1f002adbf23953382e5d832af94vboxsync to the size specified as it is filled with data.</para>
447cbf113f44132911fc13dc33cb26603759b82evboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>A <emphasis role="bold">fixed-size file</emphasis> will
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync immediately occupy the file specified, even if only a fraction
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync of the virtual hard disk space is actually in use. While
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync occupying much more space, a fixed-size file incurs less
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync overhead and is therefore slightly faster than a dynamically
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync allocated file.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>For details about the differences, please refer to <xref
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>To prevent your physical hard disk from running full,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox limits the size of the image file. Still, it needs to be
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync large enough to hold the contents of your operating system and the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync applications you want to install -- for a modern Windows or Linux
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync guest, you will probably need several gigabytes for any serious
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync use:</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <mediaobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imagedata align="center" fileref="images/create-vdi-1.png"
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync width="10cm" />
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </mediaobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>After having selected or created your image file, again press
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <emphasis role="bold">"Next"</emphasis> to go to the next
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync page.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>After clicking on <emphasis role="bold">"Finish"</emphasis>,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync your new virtual machine will be created. You will then see it in
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the list on the left side of the Manager window, with the name you
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync entered initially.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>To start a virtual machine, you have several options:<itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Double-click on its entry in the list within the Manager
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync window or</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>select its entry in the list in the Manager window it and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync press the "Start" button at the top or</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>for virtual machines created with VirtualBox 4.0 or later,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync navigate to the "VirtualBox VMs" folder in your system user's home
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync directory, find the subdirectory of the machine you want to start
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync and double-click on the machine settings file (with a
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <computeroutput>.vbox</computeroutput> file extension).</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>This opens up a new window, and the virtual machine which you
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync selected will boot up. Everything which would normally be seen on the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync virtual system's monitor is shown in the window, as can be seen with the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>In general, you can use the virtual machine much like you would use
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync a real computer. There are couple of points worth mentioning
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync however.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <title>Starting a new VM for the first time</title>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>When a VM gets started for the first time, another wizard -- the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <emphasis role="bold">"First Start Wizard"</emphasis> -- will pop up to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync help you select an <emphasis role="bold">installation medium</emphasis>.
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Since the VM is created empty, it would otherwise behave just like a
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync real computer with no operating system installed: it will do nothing and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync display an error message that no bootable operating system was
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync found.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>For this reason, the wizard helps you select a medium to install
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync an operating system from.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>If you have physical CD or DVD media from which you want to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync install your guest operating system (e.g. in the case of a Windows
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync installation CD or DVD), put the media into your host's CD or DVD
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync drive.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Then, in the wizard's drop-down list of installation media,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync select <emphasis role="bold">"Host drive"</emphasis> with the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync correct drive letter (or, in the case of a Linux host, device file).
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync This will allow your VM to access the media in your host drive, and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync you can proceed to install from there.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>If you have downloaded installation media from the Internet in
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the form of an ISO image file (most probably in the case of a Linux
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync distribution), you would normally burn this file to an empty CD or
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync DVD and proceed as just described. With VirtualBox however, you can
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync skip this step and mount the ISO file directly. VirtualBox will then
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync present this file as a CD or DVD-ROM drive to the virtual machine,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync much like it does with virtual hard disk images.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>For this case, the wizard's drop-down list contains a list of
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync installation media that were previously used with VirtualBox.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>If your medium is not in the list (especially if you are using
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox for the first time), select the small folder icon next to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the drop-down list to bring up a standard file dialog, with which
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync you can pick the image file on your host disks.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>In both cases, after making the choices in the wizard, you will be
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync able to install your operating system.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <title id="keyb_mouse_normal">Capturing and releasing keyboard and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync mouse</title>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>As of version 3.2, VirtualBox provides a virtual USB tablet device
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync to new virtual machines through which mouse events are communicated to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the guest operating system. As a result, if you are running a modern
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync guest operating system that can handle such devices, mouse support may
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync work out of the box without the mouse being "captured" as described
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync below; see <xref linkend="settings-motherboard" /> for more
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync information.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Otherwise, if the virtual machine only sees standard PS/2 mouse
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync and keyboard devices, since the operating system in the virtual machine
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync does not "know" that it is not running on a real computer, it expects to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync have exclusive control over your keyboard and mouse. This is, however,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync not the case since, unless you are running the VM in full screen mode,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync your VM needs to share keyboard and mouse with other applications and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync possibly other VMs on your host.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>As a result, initially after installing a guest operating system
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync and before you install the Guest Additions (we will explain this in a
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync minute), only one of the two -- your VM or the rest of your computer --
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync can "own" the keyboard and the mouse. You will see a
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <emphasis>second</emphasis> mouse pointer which will always be confined
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync to the limits of the VM window. Basically, you activate the VM by
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync clicking inside it.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>To return ownership of keyboard and mouse to your host operating
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync system, VirtualBox reserves a special key on your keyboard for itself:
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the <emphasis role="bold">"host key".</emphasis> By default, this is the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <emphasis>right Control key</emphasis> on your keyboard; on a Mac host,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the default host key is the left Command key. You can change this
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync default in the VirtualBox Global Settings. In any case, the current
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync setting for the host key is always displayed <emphasis>at the bottom
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync right of your VM window,</emphasis> should you have forgotten about
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imagedata align="center" fileref="images/vm-hostkey.png"
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync width="7cm" />
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </mediaobject>In detail, all this translates into the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync following:</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Your <emphasis role="bold">keyboard</emphasis> is owned by
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the VM if the VM window on your host desktop has the keyboard
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync focus (and then, if you have many windows open in your guest
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync operating system as well, the window that has the focus in your
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VM). This means that if you want to type within your VM, click on
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the title bar of your VM window first.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>To release keyboard ownership, press the Host key (as
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync explained above, typically the right Control key).</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Note that while the VM owns the keyboard, some key sequences
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync (like Alt-Tab for example) will no longer be seen by the host, but
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync will go to the guest instead. After you press the host key to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync re-enable the host keyboard, all key presses will go through the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync host again, so that sequences like Alt-Tab will no longer reach
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the guest.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Your <emphasis role="bold">mouse</emphasis> is owned by the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VM only after you have clicked in the VM window. The host mouse
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync pointer will disappear, and your mouse will drive the guest's
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync pointer instead of your normal mouse pointer.</para>
4791a729647f035b6561d292c9f848dd1fc797a9vboxsync <para>Note that mouse ownership is independent of that of the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync keyboard: even after you have clicked on a titlebar to be able to
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync type into the VM window, your mouse is not necessarily owned by
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync the VM yet.</para>
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync <para>To release ownership of your mouse by the VM, also press the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Host key.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>As this behavior can be inconvenient, VirtualBox provides a set of
4791a729647f035b6561d292c9f848dd1fc797a9vboxsync tools and device drivers for guest systems called the "VirtualBox Guest
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Additions" which make VM keyboard and mouse operation a lot more
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync seamless. Most importantly, the Additions will get rid of the second
4791a729647f035b6561d292c9f848dd1fc797a9vboxsync "guest" mouse pointer and make your host mouse pointer work directly in
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the guest.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Operating systems expect certain key combinations to initiate
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync certain procedures. Some of these key combinations may be difficult to
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync enter into a virtual machine, as there are three candidates as to who
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync receives keyboard input: the host operating system, VirtualBox, or the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync guest operating system. Who of these three receives keypresses depends
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync on a number of factors, including the key itself.</para>
b8908d384db2324f04a2f68a13e67ea32ebf609avboxsync <itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Host operating systems reserve certain key combinations for
9c0076729ec8138e89ce8a6af9a772b68f1f8dc7vboxsync themselves. For example, it is impossible to enter the <emphasis
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync role="bold">Ctrl+Alt+Delete</emphasis> combination if you want to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync reboot the guest operating system in your virtual machine, because
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync this key combination is usually hard-wired into the host OS (both
4791a729647f035b6561d292c9f848dd1fc797a9vboxsync Windows and Linux intercept this), and pressing this key combination
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync will therefore reboot your <emphasis>host</emphasis>.</para>
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync <para>Also, on Linux and Solaris hosts, which use the X Window
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync System, the key combination <emphasis
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync role="bold">Ctrl+Alt+Backspace</emphasis> normally resets the X
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync server (to restart the entire graphical user interface in case it
4791a729647f035b6561d292c9f848dd1fc797a9vboxsync got stuck). As the X server intercepts this combination, pressing it
4791a729647f035b6561d292c9f848dd1fc797a9vboxsync will usually restart your <emphasis>host</emphasis> graphical user
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync interface (and kill all running programs, including VirtualBox, in
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync the process).</para>
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync <para>Third, on Linux hosts supporting virtual terminals, the key
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync combination <emphasis role="bold">Ctrl+Alt+Fx</emphasis> (where Fx
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync is one of the function keys from F1 to F12) normally allows to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync switch between virtual terminals. As with Ctrl+Alt+Delete, these
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync combinations are intercepted by the host operating system and
4791a729647f035b6561d292c9f848dd1fc797a9vboxsync therefore always switch terminals on the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>If, instead, you want to send these key combinations to the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <emphasis>guest</emphasis> operating system in the virtual machine,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync you will need to use one of the following methods:</para>
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync <itemizedlist>
4791a729647f035b6561d292c9f848dd1fc797a9vboxsync <para>Use the items in the "Machine" menu of the virtual machine
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync window. There you will find "Insert Ctrl+Alt+Delete" and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync "Ctrl+Alt+Backspace"; the latter will only have an effect with
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Linux or Solaris guests, however.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Press special key combinations with the Host key (normally
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the right Control key), which VirtualBox will then translate for
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the virtual machine:<itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Host key + Del</emphasis> to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync send Ctrl+Alt+Del (to reboot the guest);</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Backspace</emphasis> to send Ctrl+Alt+Backspace (to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync restart the graphical user interface of a Linux or Solaris
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync guest);</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Host key + F1</emphasis> (or
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync other function keys) to simulate Ctrl+Alt+F1 (or other
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync function keys, i.e. to switch between virtual terminals in
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync a Linux guest).</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>For some other keyboard combinations such as <emphasis
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync role="bold">Alt-Tab</emphasis> (to switch between open windows),
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox allows you to configure whether these combinations will
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync affect the host or the guest, if a virtual machine currently has the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync focus. This is a global setting for all virtual machines and can be
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync found under "File" -> "Preferences" -> "Input" ->
edefdc20eedaf9ef5b1293e56ba9b8cca7b5c740vboxsync "Auto-capture keyboard".</para>
edefdc20eedaf9ef5b1293e56ba9b8cca7b5c740vboxsync </listitem>
edefdc20eedaf9ef5b1293e56ba9b8cca7b5c740vboxsync </itemizedlist>
fe9a95f96e622c50bd6463335687b799f8e3915dvboxsync <para>While a virtual machine is running, you can change removable media
fe9a95f96e622c50bd6463335687b799f8e3915dvboxsync in the "Devices" menu of the VM's window. Here you can select in detail
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync what VirtualBox presents to your VM as a CD, DVD, or floppy.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The settings are the same as would be available for the VM in the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync "Settings" dialog of the VirtualBox main window, but since that dialog
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync is disabled while the VM is in the "running" or "saved" state, this
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync extra menu saves you from having to shut down and restart the VM every
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync time you want to change media.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Hence, in the "Devices" menu, VirtualBox allows you to attach the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync host drive to the guest or select a floppy or DVD image using the Disk
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Image Manager, all as described in <xref
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>You can resize the virtual machine's window when it is running. In
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync that case, one of three things will happen:<orderedlist>
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync <para>If you have <emphasis role="bold">"scale mode"</emphasis>
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync enabled, then the virtual machine's screen will be scaled to the
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync size of the window. This can be useful if you have many machines
bd5c7d04b57ea9dfea041aad6a07cd8823b4e7c0vboxsync running and want to have a look at one of them while it is running
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync in the background. Alternatively, it might be useful to enlarge a
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync window if the VM's output screen is very small, for example
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync because you are running an old operating system in it.</para>
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync <para>To enable scale mode, press the <emphasis role="bold">host
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync key + C</emphasis>, or select "Scale mode" from the "Machine" menu
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync in the VM window. To leave scale mode, press the host key + C
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync again.</para>
9ce778d861807ac39e2be5be9e458e4f5dff0c76vboxsync <para>The aspect ratio of the guest screen is preserved when
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync resizing the window. To ignore the aspect ratio, press Shift
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync during the resize operation.</para>
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync <para>Please see <xref linkend="KnownIssues" /> for additional
9ce778d861807ac39e2be5be9e458e4f5dff0c76vboxsync remarks.</para>
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync </listitem>
b7fc0ed6c80bf49e581b983ee0039b67f001d849vboxsync <para>If you have the Guest Additions installed and they support
b7fc0ed6c80bf49e581b983ee0039b67f001d849vboxsync automatic <emphasis role="bold">resizing</emphasis>, the Guest
b7fc0ed6c80bf49e581b983ee0039b67f001d849vboxsync Additions will automatically adjust the screen resolution of the
b7fc0ed6c80bf49e581b983ee0039b67f001d849vboxsync guest operating system. For example, if you are running a Windows
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync guest with a resolution of 1024x768 pixels and you then resize the
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync VM window to make it 100 pixels wider, the Guest Additions will
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync change the Windows display resolution to 1124x768.</para>
bd5c7d04b57ea9dfea041aad6a07cd8823b4e7c0vboxsync <para>Please see <xref linkend="guestadditions" /> for more
bd5c7d04b57ea9dfea041aad6a07cd8823b4e7c0vboxsync information about the Guest Additions.</para>
bd5c7d04b57ea9dfea041aad6a07cd8823b4e7c0vboxsync </listitem>
bd5c7d04b57ea9dfea041aad6a07cd8823b4e7c0vboxsync <para>Otherwise, if the window is bigger than the VM's screen, the
bd5c7d04b57ea9dfea041aad6a07cd8823b4e7c0vboxsync screen will be centered. If it is smaller, then scroll bars will
b59225a084dd225b72dd3c2238045ef19f60aa61vboxsync be added to the machine window.</para>
b59225a084dd225b72dd3c2238045ef19f60aa61vboxsync </listitem>
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync <para>When you click on the "Close" button of your virtual machine
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync window (at the top right of the window, just like you would close any
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync other window on your system), VirtualBox asks you whether you want to
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync "save" or "power off" the VM. (As a shortcut, you can also press the
9ce778d861807ac39e2be5be9e458e4f5dff0c76vboxsync Host key together with "Q".)</para>
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync <imageobject>
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync <imagedata align="center" fileref="images/vm-close.png"
9ce778d861807ac39e2be5be9e458e4f5dff0c76vboxsync width="11cm" />
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync </imageobject>
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync </mediaobject>The difference between these three options is crucial.
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync They mean:</para>
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync <itemizedlist>
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync <para><emphasis role="bold">Save the machine state:</emphasis> With
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync this option, VirtualBox "freezes" the virtual machine by completely
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync saving its state to your local disk.</para>
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync <para>When you start the VM again later, you will find that the VM
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync continues exactly where it was left off. All your programs will
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync still be open, and your computer resumes operation. Saving the state
3dd1d8fdf12303b292d9ee378edbc5f5fb6d6cb5vboxsync of a virtual machine is thus in some ways similar to suspending a
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Send the shutdown signal.</emphasis>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync This will send an ACPI shutdown signal to the virtual machine, which
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync has the same effect as if you had pressed the power button on a real
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync computer. So long as the VM is running a fairly modern operating
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync system, this should trigger a proper shutdown mechanism from within
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the VM.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Power off the machine:</emphasis> With
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync this option, VirtualBox also stops running the virtual machine, but
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <emphasis>without</emphasis> saving its state.<warning>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>This is equivalent to pulling the power plug on a real
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync computer without shutting it down properly. If you start the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync machine again after powering it off, your operating system will
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync have to reboot completely and may begin a lengthy check of its
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync (virtual) system disks. As a result, this should not normally be
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync done, since it can potentially cause data loss or an
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync inconsistent state of the guest system on disk.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>As an exception, if your virtual machine has any snapshots
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync (see the next chapter), you can use this option to quickly <emphasis
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync role="bold">restore the current snapshot</emphasis> of the virtual
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync machine. In that case, powering off the machine will not disrupt its
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync state, but any changes made since that snapshot was taken will be
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync lost.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The <emphasis role="bold">"Discard"</emphasis> button in the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox Manager window discards a virtual machine's saved state. This
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync has the same effect as powering it off, and the same warnings
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync apply.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>With snapshots, you can save a particular state of a virtual machine
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync for later use. At any later time, you can revert to that state, even
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync though you may have changed the VM considerably since then. A snapshot of
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync a virtual machine is thus similar to a machine in "saved" state, as
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync described above, but there can be many of them, and these saved states are
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync preserved.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>You can see the snapshots of a virtual machine by first selecting a
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync machine in the VirtualBox Manager and then clicking on the "Snapshots"
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync button at the top right. Until you take a snapshot of the machine, the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync list of snapshots will be empty except for the "Current state" item, which
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync represents the "Now" point in the lifetime of the virtual machine.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <title>Taking, restoring and deleting snapshots</title>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>There are three operations related to snapshots:<orderedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>You can <emphasis role="bold">take a snapshot</emphasis>.
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync This makes a copy of the machine's current state, to which you can
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync go back at any given time later.<itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>If your VM is currently running, select "Take
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync snapshot" from the "Machine" pull-down menu of the VM
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync window.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>If your VM is currently in either the "saved" or the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync "powered off" state (as displayed next to the VM in the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox main window), click on the "Snapshots" tab on the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync top right of the main window, and then<itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>either on the small camera icon (for "Take
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync snapshot") or</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>right-click on the "Current State" item in the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync list and select "Take snapshot" from the menu.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>In any case, a window will pop up and ask you for a snapshot
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync name. This name is purely for reference purposes to help you
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync remember the state of the snapshot. For example, a useful name
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync would be "Fresh installation from scratch, no Guest Additions", or
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync "Service Pack 3 just installed". You can also add a longer text in
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the "Description" field if you want.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Your new snapshot will then appear in the snapshots list.
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync Underneath your new snapshot, you will see an item called "Current
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync state", signifying that the current state of your VM is a
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync variation based on the snapshot you took earlier. If you later
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync take another snapshot, you will see that they will be displayed in
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync sequence, and each subsequent snapshot is derived from an earlier
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync one:<mediaobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imagedata align="center" fileref="images/snapshots-1.png"
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync width="12cm" />
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>VirtualBox imposes no limits on the number of snapshots you
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync can take. The only practical limitation is disk space on your
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync host: each snapshot stores the state of the virtual machine and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync thus occupies some disk space. (See the next section for details
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync on what exactly is stored in a snapshot.)</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>You can <emphasis role="bold">restore a snapshot</emphasis>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync by right-clicking on any snapshot you have taken in the list of
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync snapshots. By restoring a snapshot, you go back (or forward) in
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync time: the current state of the machine is lost, and the machine is
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync restored to the exact state it was in when the snapshot was
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync taken.<footnote>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Both the terminology and the functionality of restoring
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync snapshots has changed with VirtualBox 3.1. Before that
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync version, it was only possible to go back to the very last
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync snapshot taken -- not earlier ones, and the operation was
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync called "Discard current state" instead of "Restore last
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync snapshot". The limitation has been lifted with version 3.1. It
4791a729647f035b6561d292c9f848dd1fc797a9vboxsync is now possible to restore <emphasis>any</emphasis> snapshot,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync going backward and forward in time.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Restoring a snapshot will affect the virtual hard drives
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync that are connected to your VM, as the entire state of the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync virtual hard drive will be reverted as well. This means also
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync that all files that have been created since the snapshot and all
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync other file changes <emphasis>will be lost. </emphasis>In order
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync to prevent such data loss while still making use of the snapshot
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync feature, it is possible to add a second hard drive in
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync "write-through" mode using the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <computeroutput>VBoxManage</computeroutput> interface and use it
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync to store your data. As write-through hard drives are
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <emphasis>not</emphasis> included in snapshots, they remain
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync unaltered when a machine is reverted. See <xref
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync linkend="hdimagewrites" os="" /> for details.</para>
859c9a7cc74066a52cf7e76d54169859e7705c3dvboxsync <para>To avoid losing the current state when restoring a snapshot,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync you can create a new snapshot before the restore.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>By restoring an earlier snapshot and taking more snapshots
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync from there, it is even possible to create a kind of alternate
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync reality and to switch between these different histories of the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync virtual machine. This can result in a whole tree of virtual
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync machine snapshots, as shown in the screenshot above.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync snapshot</emphasis>, which will not affect the state of the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync virtual machine, but only release the files on disk that
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox used to store the snapshot data, thus freeing disk
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync space. To delete a snapshot, right-click on it in the snapshots
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync tree and select "Delete". As of VirtualBox 3.2, snapshots can be
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync deleted even while a machine is running.<note>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Whereas taking and restoring snapshots are fairly quick
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync operations, deleting a snapshot can take a considerable amount
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync of time since large amounts of data may need to be copied
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync between several disk image files. Temporary disk files may
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync also need large amounts of disk space while the operation is
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync in progress.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>There are some situations which cannot be handled while a VM
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync is running, and you will get an appropriate message that you need
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync to perform this snapshot deletion when the VM is shut down.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Think of a snapshot as a point in time that you have preserved.
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync More formally, a snapshot consists of three things:<itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>It contains a complete copy of the VM settings, including
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the hardware configuration, so that when you restore a snapshot,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the VM settings are restored as well. (For example, if you changed
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the hard disk configuration or the VM's system settings, that
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync change is undone when you restore the snapshot.)</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The copy of the settings is stored in the machine
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync configuration, an XML text file, and thus occupies very little
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync space.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The complete state of all the virtual disks attached to the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync machine is preserved. Going back to a snapshot means that all
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync changes that had been made to the machine's disks -- file by file,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync bit by bit -- will be undone as well. Files that were since
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync created will disappear, files that were deleted will be restored,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync changes to files will be reverted.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>(Strictly speaking, this is only true for virtual hard disks
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync in "normal" mode. As mentioned above, you can configure disks to
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync behave differently with snapshots; see <xref
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync linkend="hdimagewrites" />. Even more formally and technically
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync correct, it is not the virtual disk itself that is restored when a
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync snapshot is restored. Instead, when a snapshot is taken,
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox creates differencing images which contain only the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync changes since the snapshot were taken, and when the snapshot is
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync restored, VirtualBox throws away that differencing image, thus
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync going back to the previous state. This is both faster and uses
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync less disk space. For the details, which can be complex, please see
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Creating the differencing image as such does not occupy much
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync space on the host disk initially, since the differencing image
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync will initially be empty (and grow dynamically later with each
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync write operation to the disk). The longer you use the machine after
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync having created the snapshot, however, the more the differencing
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync image will grow in size.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>Finally, if you took a snapshot while the machine was
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync running, the memory state of the machine is also saved in the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync snapshot (the same way the memory can be saved when you close the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VM window). When you restore such a snapshot, execution resumes at
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync exactly the point when the snapshot was taken.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The memory state file can be as large as the memory size of
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the virtual machine and will therefore occupy quite some disk
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync space as well.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <title id="configbasics">Virtual machine configuration</title>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>When you select a virtual machine from the list in the Manager
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync window, you will see a summary of that machine's settings on the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync right.</para>
447cbf113f44132911fc13dc33cb26603759b82evboxsync <para>Clicking on the "Settings" button in the toolbar at the top brings
4fac78486305f1f002adbf23953382e5d832af94vboxsync up a detailed window where you can configure many of the properties of the
447cbf113f44132911fc13dc33cb26603759b82evboxsync selected VM. But be careful: even though it is possible to change all VM
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync settings after installing a guest operating system, certain changes might
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync prevent a guest operating system from functioning correctly if done after
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync installation.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The "Settings" button is disabled while a VM is either in the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync "running" or "saved" state. This is simply because the settings dialog
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync allows you to change fundamental characteristics of the virtual computer
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync that is created for your guest operating system, and this operating
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync system may not take it well when, for example, half of its memory is
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync taken away from under its feet. As a result, if the "Settings" button is
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync disabled, shut down the current VM first.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>VirtualBox provides a plethora of parameters that can be changed for
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync a virtual machine. The various settings that can be changed in the
4791a729647f035b6561d292c9f848dd1fc797a9vboxsync "Settings" window are described in detail in <xref
4791a729647f035b6561d292c9f848dd1fc797a9vboxsync linkend="BasicConcepts" />. Even more parameters are available with the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync VirtualBox command line interface; see <xref
4791a729647f035b6561d292c9f848dd1fc797a9vboxsync <para>To remove a virtual machine which you no longer need, right-click on
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync it in the Manager's VM list select "Remove" from the context menu that
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync comes up.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>A confirmation window will come up that allows you to select whether
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the machine should only be removed from the list of machines or whether
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the files associated with it should also be deleted.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The "Remove" menu item is disabled while a machine is
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync running.</para>
6c221e25dc2b60524e787167348abb062dd89f3fvboxsync <para>To experiment with a VM configuration, test different guest OS levels
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync or to simply backup a VM, VirtualBox can create a full or a linked copy of
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync an existing VM.<footnote>Cloning support was introduced with VirtualBox
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>A wizard will guide you through the clone process:</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <mediaobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <imagedata align="center" fileref="images/clone-vm.png"
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync width="10cm" />
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </imageobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </mediaobject>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>This wizard can be invoked from the context menu of the Manager's VM
fd60bfdb327b9b1e7a6d084cf368fb7f07c566cfvboxsync list (select "Clone") or the "Snapshots" view of the selected VM. First
fd60bfdb327b9b1e7a6d084cf368fb7f07c566cfvboxsync choose a new name for the clone. When you select <emphasis
223935479ac42db56b7b7a7d16548d590022996avboxsync role="bold">Reinitialize the MAC address of all network cards</emphasis>
223935479ac42db56b7b7a7d16548d590022996avboxsync every network card get a new MAC address assigned. This is useful when
223935479ac42db56b7b7a7d16548d590022996avboxsync both, the source VM and the cloned VM, have to operate on the same network.
223935479ac42db56b7b7a7d16548d590022996avboxsync If you leave this unchanged, all network cards have the same MAC address
fd60bfdb327b9b1e7a6d084cf368fb7f07c566cfvboxsync like the one in the source VM. Depending on how you invoke the wizard you
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync have different choices for the cloning operation. First you need to decide
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync if the clone should be linked to the source VM or a fully independent clone
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync should be created:</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para><emphasis role="bold">Full clone:</emphasis> In this mode all
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync depending disk images are copied to the new VM folder. The clone
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync can fully operate without the source VM.
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync <para><emphasis role="bold">Linked clone:</emphasis> In this mode new
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync differencing disk images are created where the parent disk images
d36016c7e22c0a816c7eae1b6d53f46b7d180589vboxsync are the source disk images. If you selected the current state of
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync the source VM as clone point, a new snapshot will be created
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync implicitly.
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync </listitem>
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync </itemizedlist>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>After selecting the clone mode, you need to decide about what exactly
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync should be cloned. You can always create a clone of the <emphasis
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync role="italic">current state</emphasis> only or <emphasis
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync role="italic">all</emphasis>. When you select <emphasis
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync role="italic">all</emphasis>, the current state and in addition all
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync snapshots are cloned. Have you started from a snapshot which has additional
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync children, you can also clone the <emphasis role="italic">current state and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync all children</emphasis>. This creates a clone starting with this
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync snapshot and includes all child snaphots.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The clone operation itself can be a lengthy operation depending on
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync the size and count of the attached disk images. Also keep in mind that
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync every snapshot has differencing disk images attached, which need to be cloned
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync as well.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The "Clone" menu item is disabled while a machine is running.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>For how to clone a VM at the command line, please see <xref
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <title>Importing and exporting virtual machines</title>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>VirtualBox can import and export virtual machines in the
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync industry-standard Open Virtualization Format (OVF).<footnote>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>OVF support was originally introduced with VirtualBox 2.2 and
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync has seen major improvements with every version since.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>OVF is a cross-platform standard supported by many virtualization
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync products which allows for creating ready-made virtual machines that can
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync then be imported into a virtualizer such as VirtualBox. VirtualBox makes
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync OVF import and export easy to access and supports it from the Manager
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync window as well as its command-line interface. This allows for packaging
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync so-called <emphasis role="bold">virtual appliances</emphasis>: disk images
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync together with configuration settings that can be distributed easily. This
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync way one can offer complete ready-to-use software packages (operating
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync systems with applications) that need no configuration or installation
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync except for importing into VirtualBox.<note>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync <para>The OVF standard is complex, and support in VirtualBox is an
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync ongoing process. In particular, no guarantee is made that VirtualBox
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync supports all appliances created by other virtualization software. For
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync a list of known limitations, please see <xref
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync <para>Appliances in OVF format can appear in two variants:<orderedlist>
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync <para>They can come in several files, as one or several disk images,
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync typically in the widely-used VMDK format (see <xref
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync linkend="vdidetails" />) and a textual description file in an XML
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync dialect with an <computeroutput>.ovf</computeroutput> extension.
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync These files must then reside in the same directory for VirtualBox to
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync be able to import them.</para>
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync </listitem>
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync <para>Alternatively, the above files can be packed together into a
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync single archive file, typically with an
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync <computeroutput>.ova</computeroutput> extension. (Such archive files
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync use a variant of the TAR archive format and can therefore be
30a7a1ba4558de8e809ab4bdbd82a713d67e59abvboxsync unpacked outside of VirtualBox with any utility that can unpack
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync standard TAR files.)</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </listitem>
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync <para>To <emphasis role="bold">import</emphasis> an appliance in one of
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync the above formats, simply double-click on the OVF/OVA file.<footnote>
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync <para>Starting with version 4.0, VirtualBox creates file type
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync associations for OVF and OVA files on your host operating
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync system.</para>
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </footnote> Alternatively, select "File" -> "Import appliance" from
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync the Manager window. In the file dialog that comes up, navigate to the file
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync with either the <computeroutput>.ovf</computeroutput> or the
174f11bbd5c277153742aa5e6c3bd640bf379547vboxsync <computeroutput>.ova</computeroutput> file extension.</para>
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync <para>If VirtualBox can handle the file, a dialog similar to the following
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync will appear:</para>
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync <imageobject>
80e46f984efd827517661c0e081a36014ca41af8vboxsync <imagedata align="center" fileref="images/ovf-import.png"
80e46f984efd827517661c0e081a36014ca41af8vboxsync width="12cm" />
febf3f1de573e25fb134b8453a22b0732b4c52e2vboxsync </imageobject>
1e9377d042fa2ea3e2cd78805678f23f64db55f6vboxsync </mediaobject>This presents the virtual machines described in the OVF
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync file and allows you to change the virtual machine settings by
fa2d3f7a92b98db2c47964694f4b7e1aa67a3b10vboxsync double-clicking on the description items. Once you click on <emphasis
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync role="bold">"Import"</emphasis>, VirtualBox will copy the disk images and
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync create local virtual machines with the settings described in the dialog.
174f11bbd5c277153742aa5e6c3bd640bf379547vboxsync These will then show up in the Manager's list of virtual machines.</para>
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync <para>Note that since disk images tend to be big, and VMDK images that
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync come with virtual appliances are typically shipped in a special compressed
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync format that is unsuitable for being used by virtual machines directly, the
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync images will need to be unpacked and copied first, which can take a few
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync minutes.</para>
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync <para>For how to import an image at the command line, please see <xref
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync <para>Conversely, to <emphasis role="bold">export</emphasis> virtual
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync machines that you already have in VirtualBox, select "File" -> "Export
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync appliance". A different dialog window shows up that allows you to combine
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync several virtual machines into an OVF appliance. Then, select the target
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync location where the target files should be stored, and the conversion
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync process begins. This can again take a while.</para>
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync <para>For how to export an image at the command line, please see <xref
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync <para>OVF cannot describe snapshots that were taken for a virtual
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync machine. As a result, when you export a virtual machine that has
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync snapshots, only the current state of the machine will be exported, and
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync the disk images in the export will have a "flattened" state identical
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync to the current state of the virtual machine.</para>
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync <para>As briefly mentioned in <xref linkend="features-overview" />,
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync VirtualBox has a very flexible internal design that allows for using
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync multiple interfaces to control the same virtual machines. To illustrate,
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync you can, for example, start a virtual machine with the VirtualBox Manager
223935479ac42db56b7b7a7d16548d590022996avboxsync window and then stop it from the command line. With VirtualBox's support
174f11bbd5c277153742aa5e6c3bd640bf379547vboxsync for the Remote Desktop Protocol (RDP), you can even run virtual machines
174f11bbd5c277153742aa5e6c3bd640bf379547vboxsync remotely on a headless server and have all the graphical output redirected
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync over the network.</para>
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync <para>In detail, the following front-ends are shipped in the standard
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync VirtualBox package:</para>
223935479ac42db56b7b7a7d16548d590022996avboxsync <para><computeroutput>VirtualBox</computeroutput> is the VirtualBox
174f11bbd5c277153742aa5e6c3bd640bf379547vboxsync Manager. This graphical user interface uses the Qt toolkit; most of
174f11bbd5c277153742aa5e6c3bd640bf379547vboxsync this User Manual is dedicated to describing it. While this is the
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync easiest to use, some of the more advanced VirtualBox features are
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync kept away from it to keep it simple.</para>
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync </listitem>
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync <para><computeroutput>VBoxManage</computeroutput> is our
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync command-line interface for automated and very detailed control of
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync every aspect of VirtualBox. It is described in <xref
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync </listitem>
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync <para><computeroutput>VBoxSDL</computeroutput> is an alternative,
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync simple graphical front-end with an intentionally limited feature
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync set, designed to only display virtual machines that are controlled
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync in detail with <computeroutput>VBoxManage</computeroutput>. This is
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync interesting for business environments where displaying all the bells
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync and whistles of the full GUI is not feasible.
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync <computeroutput>VBoxSDL</computeroutput> is described in <xref
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync </listitem>
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync <para>Finally, <computeroutput>VBoxHeadless</computeroutput> is yet
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync another front-end that produces no visible output on the host at
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync all, but merely acts as a RDP server if the VirtualBox Remote
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync Desktop Extension (VRDE) is installed. As opposed to the other
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync graphical interfaces, the headless front-end requires no graphics
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync support. This is useful, for example, if you want to host your
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync virtual machines on a headless Linux server that has no X Window
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync system installed. For details, see <xref
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync </listitem>
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync </orderedlist>If the above front-ends still do not satisfy your
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync particular needs, it is possible to create yet another front-end to the
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync complex virtualization engine that is the core of VirtualBox, as the
cf289c84a0ecd24e5808b46b70d545cdc2c8805cvboxsync VirtualBox core neatly exposes all of its features in a clean API; please