user_BasicConcepts.xml revision 6728a36898fd2be125a28e84d2115d19aa4923ed
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN"
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync "http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd">
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Whereas <xref linkend="Introduction" /> gave you a quick introduction
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync to VirtualBox and how to get your first virtual machine running, the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync following chapter describe in detail how to configure virtual
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync machines.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>You have considerable latitude in deciding what virtual hardware will
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync be provided to the guest. The virtual hardware can be used for communicating
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync with the host system or with other guests. For instance, if you provide
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync VirtualBox with the image of a CD-ROM in an ISO file, VirtualBox can present
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync this image to a guest system as if it were a physical CD-ROM. Similarly, you
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync can give a guest system access to the real network via its virtual network
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync card, and, if you choose, give the host system, other guests, or computers
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync on the Internet access to the guest system.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <title id="guestossupport">Supported guest operating systems</title>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Since VirtualBox is designed to provide a generic virtualization
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync environment for x86 systems, it may run operating systems of any kind,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync even those that are not officially supported by $VBOX_VENDOR. However, our
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync focus is to optimize the product's performance for a select list of guest
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync systems:</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>All versions/editions and service packs are fully supported;
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync however, there are some issues with older service packs. We
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync recommend to install service pack 6a. Guest Additions are
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync available with a limited feature set.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossterm>Windows 2000 / XP / Server 2003 / Vista / Server 2008 /
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Windows 7</glossterm>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>All versions/editions and service packs are fully supported
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync (including 64-bit versions, under the preconditions listed below).
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Guest Additions are available.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossterm>DOS / Windows 3.x / 95 / 98 / ME</glossterm>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Limited testing has been performed. Use beyond legacy
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync installation mechanisms not recommended. No Guest Additions
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync available.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>All versions/editions are fully supported (32 bits and 64
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync bits). Guest Additions are available.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>We strongly recommend using a Linux kernel version 2.6.13 or
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync higher for better performance.<note>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Certain Linux kernel releases have bugs that prevent
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync them from executing in a virtual environment; please see <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync linkend="trouble-linux-buggy" /> for details.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Fully supported (32 bits and 64 bits). Guest Additions are
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync available.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Requires hardware virtualization to be enabled. Limited
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync support. Guest Additions are not available yet.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Requires hardware virtualization to be enabled. Versions 3.7
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync and later are supported. Guest Additions are not available
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync yet.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Requires hardware virtualization to be enabled. We
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync officially support MCP2 only; other OS/2 versions may or may not
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync work. Guest Additions are available with a limited feature
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync set.<footnote>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>VirtualBox 3.2 added experimental support for Mac OS X
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Server guests, but this comes with restrictions. Please see the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync following section as well as <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Starting with version 3.2, VirtualBox has experimental support for
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Mac OS X Server guests. This allows you to install and execute
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync unmodified versions of Mac OS X Server on supported host
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync hardware.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Whereas competing solutions perform modifications to the Mac OS X
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Server install DVDs (e.g. different boot loader and replaced files),
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync VirtualBox is the first product to provide the modern PC architecture
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync expected by OS X without requiring any "hacks".</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>You should be aware of a number of <emphasis role="bold">important
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync issues</emphasis> before attempting to install a Mac OS X Server
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync guest:<orderedlist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Mac OS X is commercial, licensed software and contains both
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync license and technical restrictions that limit its use to certain
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync hardware and usage scenarios. It is important that you understand
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync and obey these restrictions. Only the Mac OS X Server is designed
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync to be used in a virtual environment and therefore, VirtualBox does
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync not support Mac OS X client as a guest.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>As a result, before attempting to install Mac OS X Server in
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync a virtual machine, make sure you understand the <emphasis
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync role="bold">license restrictions</emphasis> of the Mac OS X
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync version you want to use. For most versions of Mac OS X Server,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Apple prohibits installing them on non-Apple hardware.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>These license restrictions are also enforced on a technical
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync level: Mac OS X Server verifies whether it is running on Apple
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync hardware, and most DVDs that that come with Apple hardware even
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync check for an exact model. These restrictions are
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <emphasis>not</emphasis> circumvented by VirtualBox and continue
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync to apply.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Only <emphasis role="bold">CPUs</emphasis> known and tested
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync by Apple are supported. As a result, if the Intel CPU is newer
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync than the build of Mac OS X Server, it will most likely panic
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync during bootup with an "Unsupported CPU" exception. It is generally
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync best to use the Mac OS X Server DVD that came with your Apple
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync hardware.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>The Mac OS X Server installer expects the harddisk to be
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <emphasis role="bold">partitioned</emphasis> so when it does not
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync offer a selection, you have to launch the Disk Utility from the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync "Tools" menu and partition the hard disk. Then close the Disk
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Utility and proceed with the installation.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In addition, as Mac OS X Server support in VirtualBox is
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync currently still experimental, please refer also to <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Starting with version 2.0, VirtualBox supports 64-bit guest
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync operating systems. Starting with version 2.1, you can even run 64-bit
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync guests on a 32-bit host operating system. The hardware prerequisites are
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync identical for both cases.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In particular, 64-bit guests are supported under the following
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync conditions:<orderedlist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>You need a 64-bit processor with hardware virtualization
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>You must enable hardware virtualization for the particular
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync VM for which you want 64-bit support; software virtualization is
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync not supported for 64-bit VMs.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If you want to use 64-bit guest support on a 32-bit host
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync operating system, you must also select a 64-bit operating system
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync for the particular VM. Since supporting 64 bits on 32-bit hosts
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync incurs additional overhead, VirtualBox only enables this support
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync upon explicit request.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>On 64-bit hosts, 64-bit guest support is always enabled, so
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync you can simply install a 64-bit operating system in the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync guest.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>On any host, you should enable the <emphasis role="bold">I/O
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync APIC</emphasis> for virtual machines that you intend to use in
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync 64-bit mode. This is especially true for 64-bit Windows VMs. See
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <xref linkend="settings-general-advanced" />. In addition, for
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync 64-bit Windows guests, you should make sure that the VM uses the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <emphasis role="bold">Intel networking device</emphasis>, since
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync there is no 64-bit driver support for the AMD PCNet card; see <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If you use the "Create VM" wizard of the VirtualBox graphical user
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync interface (see <xref linkend="gui-createvm" />), VirtualBox will
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync automatically use the correct settings for each selected 64-bit
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync operating system type.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>VirtualBox virtualizes nearly all hardware of the host. Depending on
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync a VM's configuration, the guest will see the following virtual
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync hardware:<itemizedlist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para><emphasis role="bold">Input devices.</emphasis> By default,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync VirtualBox emulates a standard PS/2 keyboard and mouse. These
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync devices are supported by almost all past and present operating
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync systems. In addition, VirtualBox can provide virtual USB input
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync devices.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para><emphasis role="bold">Graphics.</emphasis> the VirtualBox
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync graphics device (sometimes referred to as VGA device) is, unlike
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync nearly all other emulated devices, not based on any physical
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync counterpart. It is a simple, synthetic device which provides
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync compatibility with standard VGA and several extended registers used
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync by VESA BIOS Extensions (VBE).</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para><emphasis role="bold">Storage.</emphasis> VirtualBox currently
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync emulates the standard ATA interface found on Intel PIIX3/PIIX4
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync chips, SATA (AHCI) interface, and two SCSI adapters (LSI Logic and
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync BusLogic); see <xref linkend="harddiskcontrollers" /> for details.
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Whereas providing one of these would be enough for VirtualBox by
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync itself, this multitude of storage adapters is required for
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync compatibility with other hypervisors. Windows is particularly picky
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync about its boot devices, and migrating VMs between hypervisors is
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync very difficult or impossible if the storage controllers are
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync different.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para><emphasis role="bold">Networking.</emphasis> See <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para><emphasis role="bold">USB.</emphasis> VirtualBox emulates two
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync USB host controllers, EHCI and OHCI. There is a need for two host
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync controllers because OHCI only handles USB low- and full-speed
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync devices (both USB 1.x and 2.0), while EHCI only handles high-speed
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync devices (USB 2.0 only). The emulated USB controllers do not
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync communicate directly with devices on the host but rather with the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync VUSB layer (see below), which abstracts the USB protocol and allows
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the use of remote USB devices (with VRDP).</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para><emphasis role="bold">Audio.</emphasis> Two audio devices are
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync emulated, an AC97 controller plus codec, and a classic SoundBlaster
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync 16 (digital audio only).</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In the Settings window, under "General", you can configure the most
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync fundamental aspects of the virtual machine such as memory and essential
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync hardware. There are three tabs, "Basic", "Advanced" and
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync "Description".</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Under the "Basic" tab of the "General" settings category, you can
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync find these settings:</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glosslist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>The name under which the VM is shown in the list of VMs in
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the main window. Under this name, VirtualBox also saves the VM's
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync configuration files. By changing the name, VirtualBox renames
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync these files as well. As a result, you can only use characters
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync which are allowed in your host operating system's file
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync names.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Note that internally, VirtualBox uses unique identifiers
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync (UUIDs) to identify virtual machines. You can display these with
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <computeroutput>VBoxManage</computeroutput>.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>The type of the guest operating system that is (or will be)
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync installed in the VM. This is the same setting that was specified
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync in the "New Virtual Machine" wizard, as described with <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glosslist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>By default, VirtualBox saves snapshot data together with
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync your other VirtualBox configuration data; see <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync linkend="vboxconfigdata" />. With this setting, you can specify
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync any other folder for each VM.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If the virtual machine has Guest Additions installed, you
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync can select here whether the clipboard of the guest operating
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync system should be shared with that of your host. If you select
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync "Bidirectional", then VirtualBox will always make sure that both
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync clipboards contain the same data. If you select "Host to guest"
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync or "Guest to host", then VirtualBox will only ever copy
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync clipboard data in one direction.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossterm>Removable Media: Remember Runtime Changes</glossterm>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If this is checked, VirtualBox will save the state of what
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync media has been mounted between several runs of a virtual
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync machine.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In full screen or seamless mode, VirtualBox can display a
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync small toolbar that contains some of the items that are normally
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync available from the virtual machine's menu bar. This toolbar
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync reduces itself to a small gray line unless you move the mouse
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync over it. With the toolbar, you can return from full screen or
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync seamless mode, control machine execution or enable certain
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync devices. If you don't want to see the toolbar, disable this
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync setting.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Here you can enter any description for your virtual machine, if
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync you want. This has no effect of the functionality of the machine, but
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync you may find this space useful to note down things like the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync configuration of a virtual machine and the software that has been
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync installed into it.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>The "System" category groups various settings that are related to
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the basic hardware that is presented to the virtual machine.<note>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>As the activation mechanism of Microsoft Windows is sensitive to
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync hardware changes, if you are changing hardware settings for a Windows
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync guest, some of these changes may trigger a request for another
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync activation with Microsoft.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>On the "Motherboard" tab, you can influence virtual hardware that
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync would normally be on the motherboard of a real computer.<glosslist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>This sets the amount of RAM that is allocated and given to
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the VM when it is running. The specified amount of memory will
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync be requested from the host operating system, so it must be
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync available or made available as free memory on the host when
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync attempting to start the VM and will not be available to the host
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync while the VM is running. This is the same setting that was
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync specified in the "New Virtual Machine" wizard, as described with
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync guidelines under <xref linkend="gui-createvm" /> above.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Generally, it is possible to change the memory size after
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync installing the guest operating system (provided you do not
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync reduce the memory to an amount where the operating system would
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync no longer boot).</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>This setting determines the order in which the guest
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync operating system will attempt to boot from the various virtual
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync boot devices. Analogous to a real PC's BIOS setting, VirtualBox
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync can tell a guest OS to start from the virtual floppy, the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync virtual CD/DVD drive, the virtual hard drive (each of these as
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync defined by the other VM settings), the network, or none of
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync these.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If you select "Network", the VM will attempt to boot from
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync a network via the PXE mechanism. This needs to be configured in
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync detail on the command line; please see <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Advanced Programmable Interrupt Controllers (APICs) are a
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync newer x86 hardware feature that have replaced old-style
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Programmable Interrupt Controllers (PICs) in recent years. With
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync an I/O APIC, operating systems can use more than 16 interrupt
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync requests (IRQs) and therefore avoid IRQ sharing for improved
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync reliability.<note>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Enabling the I/O APIC is <emphasis>required</emphasis>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync for 64-bit guest operating systems, especially Windows
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Vista; it is also required if you want to use more than one
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync virtual CPU in a virtual machine.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>However, software support for I/O APICs has been
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync unreliable with some operating systems other than Windows. Also,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the use of an I/O APIC slightly increases the overhead of
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync virtualization and therefore slows down the guest OS a
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync little.<warning>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>All Windows operating systems starting with Windows
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync 2000 install different kernels depending on whether an I/O
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync APIC is available. As with ACPI, the I/O APIC therefore
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <emphasis>must not be turned off after
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync installation</emphasis> of a Windows guest OS. Turning it on
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync after installation will have no effect however.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>This enables Extensible Firmware Interface (EFI), which
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync replaces the legacy BIOS, which may be useful for certain
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync advanced use cases. Please refer to <xref linkend="efi" /> for
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync details.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If checked, VirtualBox will report the system time in UTC
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync format to the guest instead of local (host) time. This affects
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync how the virtual real-time clock (RTC) operates and may be useful
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync for Unix-like guest operating systems, which typically expect
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the hardware clock to be set to UTC.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossterm>Enable absolute pointing device</glossterm>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If enabled, VirtualBox reports to the virtual machine that
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync a USB tablet device is present and communicates mouse events to
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the virtual machine through this device. If disabled, mouse
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync events are communicated through a traditional PS/2 virtual mouse
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync device.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Using the virtual USB tablet has the advantage that
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync movements are reported in absolute coordinates (instead of as
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync relative position changes), which allows VirtualBox to translate
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync mouse events over the VM window into tablet events without
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync having to "capture" the mouse in the guest as described in <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync linkend="keyb_mouse_normal" />. This makes using the VM less
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync tedious even if Guest Additions are not installed.<footnote>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>The virtual USB tablet was added with VirtualBox 3.2.
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Depending on the guest operating system selected, this is
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync now enabled by default for new virtual machines.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In addition, you can turn off the <emphasis role="bold">Advanced
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Configuration and Power Interface (ACPI)</emphasis> which VirtualBox
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync presents to the guest operating system by default. ACPI is the current
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync industry standard to allow operating systems to recognize hardware,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync configure motherboards and other devices and manage power. As all modern
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync PCs contain this feature and Windows and Linux have been supporting it
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync for years, it is also enabled by default in VirtualBox. It can only be
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync turned off on the command line; see <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>All Windows operating systems starting with Windows 2000
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync install different kernels depending on whether ACPI is available, so
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync ACPI <emphasis>must not be turned off</emphasis> after installation
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync of a Windows guest OS. Turning it on after installation will have no
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync effect however.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>On the "Processor" tab, you can set how many virtual <emphasis
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync role="bold">CPU cores</emphasis> the guest operating systems should see.
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Starting with version 3.0, VirtualBox supports symmetrical
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync multiprocessing (SMP) and can present up to 32 virtual CPU cores to each
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync virtual machine.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>You should not, however, configure virtual machines to use more
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync CPU cores than you have available physically.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In addition, the <emphasis role="bold">"Enable PAE/NX"</emphasis>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync setting determines whether the PAE and NX capabilities of the host CPU
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync will be exposed to the virtual machine. PAE stands for "Physical Address
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Extension". Normally, if enabled and supported by the operating system,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync then even a 32-bit x86 CPU can access more than 4 GB of RAM. This is
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync made possible by adding another 4 bits to memory addresses, so that with
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync 36 bits, up to 64 GB can be addressed. Some operating systems (such as
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Ubuntu Server) require PAE support from the CPU and cannot be run in a
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync virtual machine without it.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>With virtual machines running modern server operating systems,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync VirtualBox also supports CPU hot-plugging. For details about this,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync please refer to <xref linkend="cpuhotplug" />.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>On this page, you can determine whether and how VirtualBox should
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync use hardware virtualization extensions that your host CPU may support.
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync This is the case with most CPUs built after 2006.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>You can select for each virtual machine individually whether
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync VirtualBox should use software or hardware virtualization.<footnote>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Prior to VirtualBox version 2.2, software virtualization was
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the default; starting with version 2.2, VirtualBox will enable
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync hardware virtualization by default for new virtual machines that you
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync create. (Existing virtual machines are not automatically changed for
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync compatibility reasons, and the default can of course be changed for
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync each virtual machine.)</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In most cases, the default settings will be fine; VirtualBox will
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync have picked sensible defaults depending on the operating system that you
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync selected when you created the virtual machine. In certain situations,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync however, you may want to change these preconfigured defaults.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Advanced users may be interested in technical details about
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync software vs. hardware virtualization; please see <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If your host's CPU supports the <emphasis role="bold">nested
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync paging</emphasis> (AMD-V) or <emphasis role="bold">EPT</emphasis> (Intel
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync VT-x) features, then you can expect a significant performance increase
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync by enabling nested paging in addition to hardware virtualization. Nested
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync paging is still disabled by default even for new machines, but it can be
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync enabled for each virtual machine individually. For technical details,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glosslist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>This sets the size of the memory provided by the virtual
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync graphics card available to the guest, in MB. As with the main
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync memory, the specified amount will be allocated from the host's
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync resident memory. Based on the amount of video memory, higher
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync resolutions and color depths may be available.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>With this setting VirtualBox can provide more than one virtual
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync monitor to a virtual machine. If a guest operating system (such as
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Windows) supports multiple attached monitors, VirtualBox can pretend
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync that multiple virtual monitors are present.<footnote>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Multiple monitor support was added with VirtualBox
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync 3.2.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </footnote> Up to 8 such virtual monitors are supported.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>The output of the multiple monitors will be displayed on the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync host in multiple VM windows which are running side by side.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>However, in fullscreen and seamless mode, they will use the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync available physical monitors attached to the host. As a result, for
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync fullscreen and seamless modes to work with multiple monitors, you
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync will need at least as many physical monitors as you have virtual
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync monitors configured, or VirtualBox will report an error. You can
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync configure the relationship between guest and host monitors using the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync view menu by pressing Host key + Home when you are in fullscreen or
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync seamless mode.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Please see <xref linkend="KnownIssues" /> also.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If a virtual machine has Guest Additions installed, you can
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync select here whether the guest should support accelerated 3D
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync graphics. Please refer to <xref linkend="guestadd-3d" /> for
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync details.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossterm>Enable 2D video acceleration</glossterm>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If a virtual machine with Microsoft Windows has Guest
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Additions installed, you can select here whether the guest should
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync support accelerated 2D video graphics. Please refer to <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Under the "Remote display" tab, you can enable the VRDP server
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync that is built into VirtualBox to allow you to connect to the virtual
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync machine remotely. For this, you can use any standard RDP viewer,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync such as <computeroutput>mstsc.exe</computeroutput> that comes with
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Microsoft Windows or, on Linux systems, the standard open-source
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <computeroutput>rdesktop</computeroutput> program. These features
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync are described in detail in <xref linkend="vrdp" />.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossdef>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glossentry>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </glosslist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In the VM Settings window, the "Storage" section allows you to
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync connect virtual hard disk, CD/DVD and floppy images and drives to your
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync virtual machine:<mediaobject>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <imageobject>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <imagedata align="center" fileref="images/vm-settings-harddisk.png"
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync width="10cm" />
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </imageobject>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In a real PC, so-called "storage controllers" connect physical disk
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync drives to the rest of the computer. Similarly, VirtualBox presents virtual
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync storage controllers to a virtual machine. Under each controller, the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync virtual devices (hard disks, CD/DVD or floppy drives) are shown that are
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync attached to the controller.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If you have used the "Create VM" wizard to create a machine, you
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync will normally see the following devices:<itemizedlist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>You will see an IDE controller, under which there are two
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync devices:<itemizedlist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>one virtual hard disk connected to the IDE slot called
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync "primary master"; this is represented by the disk images that
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync you created with the machine;</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>one virtual CD/DVD drive connected to the "secondary
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync master".</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In addition, there is a floppy controller to which a virtual
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync floppy drive is attached.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>You can modify these media attachments freely. For example, if you
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync wish to copy some files from another virtual disk that you created, you
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync can connect that disk as a second hard disk. You could also add a second
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync virtual CD/DVD drive, or change where these items are attached.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In addition to the IDE controller, VirtualBox can also present an
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync SATA controller and a SCSI controller to the guest, which gives you 30 or
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync 16 additional slots to attach devices to, respectively. This, however, may
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync require that you run a modern guest operating system. See <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync linkend="harddiskcontrollers" /> for details.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>To <emphasis role="bold">add another virtual hard disk or CD/DVD
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync drive,</emphasis> select the storage controller to which it should be
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync added (IDE, SATA or SCSI) and then click on the "add disk" button below
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the tree. You can then either select "Add CD/DVD device" or "Add Hard
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Disk". Alternatively, right-click on the storage controller and select a
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync menu item there.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>On the right part of the window, you can then select where the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync virtual disk should be connected to on the controller and which image file
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync to use.<itemizedlist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>For virtual hard disks, a drop-down list appears on the right,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync listing all the hard disk images that VirtualBox currently knows
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync about. If you click on the "Open Virtual Media Manager" icon to the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync right, this will bring up a window in which you can select or create
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync a different hard disk image (see <xref linkend="vdis" /> for
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync details).</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>For virtual CD/DVD drives, there are two kinds of options in
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the drop-down list.<itemizedlist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If you select "Empty", then VirtualBox will present a
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync virtual CD/DVD drive to the guest which has no media
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync inserted.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If you select "Host drive" from the list, then the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync physical device of the host computer is connected to the VM,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync so that the guest operating system can read from and write to
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync your physical device. This is, for instance, useful if you
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync want to install Windows from a real installation CD. In this
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync case, select your host drive from the drop-down list
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync presented.<note>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If you want to write CDs or DVDs using the host
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync drive, you need to enable a special setting first; see
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>The other items in the list, like virtual hard disk
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync images, will be image files on your host. The file format here
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync is the ISO format. Most commonly, you will select this option
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync when installing an operating system from an ISO file that you
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync have obtained from the Internet. For example, most Linux
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync distributions are available in this way.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>The identification string of the drive provided to the guest
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync (which, in the guest, would be displayed by configuration tools
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync such as the Windows Device Manager) is always "VBOX CD-ROM",
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync irrespective of the current configuration of the virtual drive.
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync This is to prevent hardware detection from being triggered in the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync guest operating system every time the configuration is
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync changed.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Note that the floppy controller is special: you cannot add devices
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync other than floppy drives to it. Virtual floppy drives, like virtual CD/DVD
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync drives, can be connected to either a host floppy drive (if you have one)
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync or a disk image, which in this case must be in RAW format.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>To <emphasis role="bold">remove a virtual disk or drive,</emphasis>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync select it and click on the "remove" icon at the bottom (or right-click on
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync it and select the menu item).</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Removable media (CD/DVDs and floppies) can be changed while the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync guest is running. Since the "Settings" dialog is not available at that
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync time, you can also access these settings from the "Devices" menu of your
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync virtual machine window.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>We have dedicated an entire chapter of this User Manual to virtual
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync storage: please see <xref linkend="storage" /> for every single detail
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync about storage configuration.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>The "Audio" section in a virtual machine's Settings window
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync determines whether the VM will see a sound card connected, and whether the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync audio output should be heard on the host system.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If audio is enabled for a guest, you can choose between the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync emulation of an Intel AC'97 controller or a SoundBlaster 16 card. In any
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync case, you can select what audio driver VirtualBox will use on the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync host.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>On a Linux host, depending on your host configuration, you can also
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync select between the OSS, ALSA or the PulseAudio subsystem. On newer Linux
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync distributions (Fedora 8 and above, Ubuntu 8.04 and above) the PulseAudio
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync subsystem should be preferred.<note>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Newer Windows versions do not ship with drivers for the virtual
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync audio hardware emulated by VirtualBox. This applies to Windows 7
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync (32-bit and 64-bit versions) as well as 64-bit Windows Vista. See
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <xref linkend="win7_audio" /> for instructions how to solve this
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync problem.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>The "Network" section in a virtual machine's Settings window allows
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync you to configure how VirtualBox presents virtual network cards to your VM,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync and how they operate.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>When you first create a virtual machine, VirtualBox by default
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync enables one virtual network card and selects the "Network Address
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Translation" (NAT) mode for it. This way the guest can connect to the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync outside world using the host's networking and the outside world can
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync connect to services on the guest which you choose to make visible outside
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync of the virtual machine. In most cases, this default setup will work fine
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync for you.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>However, VirtualBox is extremely flexible in how it can virtualize
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync networking. It supports up to eight virtual network cards per virtual
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync machine, the first four of which can be configured in detail in the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync graphical user interface. All eight network cards can be configured on the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync command line with VBoxManage. Because of this, we have dedicated an entire
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync chapter of this manual to discussing networking configuration; please see
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>VirtualBox fully supports virtual serial ports in a virtual machine
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync in an easy-to-use manner.<footnote>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Serial port support was added with VirtualBox 1.5.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Ever since the original IBM PC, personal computers have been
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync equipped with one or two serial ports (also called COM ports by DOS and
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Windows). While these are no longer as important as they were until a few
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync years ago (especially since mice are no longer connected to serial ports
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync these days), there are still some important uses left for them. For
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync example, serial ports can be used to set up a primitive network over a
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync null-modem cable, in case Ethernet is not available. Also, serial ports
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync are indispensable for system programmers needing to do kernel debugging,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync since kernel debugging software usually interacts with developers over a
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync serial port. In other words, with virtual serial ports, system programmers
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync can do kernel debugging on a virtual machine instead of needing a real
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync computer to connect to.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>If a virtual serial port is enabled, the guest operating system sees
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync it a standard 16450-type serial port. Both receiving and transmitting data
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync is supported. How this virtual serial port is then connected to the host
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync is configurable, and details depend on your host operating system.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>You can use either the graphical user interface or the command-line
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <computeroutput>VBoxManage</computeroutput> tool to set up virtual serial
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync ports. For the latter, please refer to <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync linkend="vboxmanage-modifyvm" />; in that section, look for the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <computeroutput>--uartmode</computeroutput> options.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In either case, you can configure up to two virtual serial ports
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync simultaneously. For each such device, you will need to
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync determine<orderedlist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>what kind of serial port the virtual machine should see by
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync selecting an I/O base address and interrupt (IRQ). For these, we
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync recommend to use the traditional values<footnote>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync url="http://en.wikipedia.org/wiki/COM_(hardware_interface)">http://en.wikipedia.org/wiki/COM_(hardware_interface)</ulink>.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Then, you will need to determine what this virtual port should
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync be connected to. For each virtual serial port, you have the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync following options:</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>You can elect to have the virtual serial port
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync "disconnected", which means that the guest will see it as
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync hardware, but it will behave as if no cable had been connected
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync to it.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>You can connect the virtual serial port to a physical
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync serial port on your host. (On a Windows host, this will be a
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync name like <computeroutput>COM1</computeroutput>; on Linux or
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync OpenSolaris hosts, it will be a device node like
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <computeroutput>/dev/ttyS0</computeroutput>). VirtualBox will
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync then simply redirect all data received from and sent to the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync virtual serial port to the physical device.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>You can tell VirtualBox to connect the virtual serial
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync port to a software pipe on the host. This depends on your host
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync operating system:<itemizedlist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>On a Windows host, data will be sent and received
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync through a named pipe. You can use a helper program
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync called VMware Serial Line Gateway, available for
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync url="http://www.l4ka.org/tools/vmwaregateway.php">http://www.l4ka.org/tools/vmwaregateway.php</ulink>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </literal>. This tool provides a fixed server mode named
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <computeroutput>\\.\pipe\vmwaredebug</computeroutput>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync and connects incoming TCP connections on port 567 with
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the named pipe.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>On a Mac, Linux or OpenSolaris host, a local
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync domain socket is used instead. On Linux there are
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync various tools which can connect to a local domain socket
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync or create one in server mode. The most flexible tool is
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <computeroutput>socat</computeroutput> and is available
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync as part of many distributions.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In this case, you can configure whether VirtualBox
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync should create the named pipe (or, on non-Windows hosts, the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync local domain socket) itself or whether VirtualBox should
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync assume that the pipe (or socket) exists already. With the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <computeroutput>VBoxManage</computeroutput> command-line
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync options, this is referred to as "server" or "client" mode,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync respectively.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </orderedlist>Up to two serial ports can be configured simultaneously
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync per virtual machine, but you can pick any port numbers out of the above.
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync For example, you can configure two serial ports to be able to work with
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync COM2 and COM4 in the guest.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>The "USB" section in a virtual machine's Settings window allows
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync you to configure VirtualBox's sophisticated USB support.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>VirtualBox can allow virtual machines to access the USB devices on
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync your host directly. To achieve this, VirtualBox presents the guest
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync operating system with a virtual USB controller. As soon as the guest
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync system starts using a USB device, it will appear as unavailable on the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync host.<note>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <orderedlist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Be careful with USB devices that are currently in use on
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the host! For example, if you allow your guest to connect to
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync your USB hard disk that is currently mounted on the host, when
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the guest is activated, it will be disconnected from the host
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync without a proper shutdown. This may cause data loss.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Solaris hosts have a few known limitations regarding USB
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync support; please see <xref linkend="KnownIssues" />.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </orderedlist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In addition to allowing a guest access to your local USB devices,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync VirtualBox even allows your guests to connect to remote USB devices by
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync use of the VRDP protocol. For details about this, see <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In the Settings dialog, you can first configure whether USB is
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync available in the guest at all, and in addition also optionally enable
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the USB 2.0 (EHCI) controller for the guest. If so, you can determine in
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync detail which devices are available. For this, you must create so-called
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync "filters" by specifying certain properties of the USB device.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Clicking on the "+" button to the right of the "USB Device
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Filters" window creates a <emphasis role="bold">new filter.</emphasis>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync You can give the filter a name (for referencing it later) and specify
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the filter criteria. The more criteria you specify, the more precisely
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync devices will be selected. For instance, if you specify only a vendor ID
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync of 046d, all devices produced by Logitech will be available to the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync guest. If you fill in all fields, on the other hand, the filter will
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync only apply to a particular device model from a particular vendor, and
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync not even to other devices of the same type with a different revision and
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync serial number.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>In detail, the following criteria are available:</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <orderedlist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para><emphasis role="bold">Vendor and product ID.</emphasis> With
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync USB, each vendor of USB products carries an identification number
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync that is unique world-wide, the "vendor ID". Similarly, each line of
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync products is assigned a "product ID" number. Both numbers are
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync commonly written in hexadecimal (that is, they are composed of the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync numbers 0-9 and the letters A-F), and a colon separates the vendor
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync from the product ID. For example,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <computeroutput>046d:c016</computeroutput> stands for Logitech as a
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync vendor, and the "M-UV69a Optical Wheel Mouse" product.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Alternatively, you can also specify <emphasis
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync role="bold">"Manufacturer"</emphasis> and <emphasis
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>To list all the USB devices that are connected to your host
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync machine with their respective vendor and product IDs, you can use
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync the following command (see <xref linkend="vboxmanage" />): <screen>VBoxManage list usbhost</screen></para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>On Windows, you can also see all USB devices that are attached
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync to your system in the Device Manager. On Linux, you can use the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <computeroutput>lsusb</computeroutput> command.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para><emphasis role="bold">Serial number.</emphasis> While vendor
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync and product ID are already quite specific to identify USB devices,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync if you have two identical devices of the same brand and product
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync line, you will also need their serial numbers to filter them out
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync correctly.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para><emphasis role="bold">Remote.</emphasis> This setting
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync specifies whether the device will be local only, or remote only
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync (over VRDP), or either.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </listitem>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync </orderedlist>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>On a Windows host, you will need to unplug and reconnect a USB
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync device to use it after creating a filter for it.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>As an example, you could create a new USB filter and specify a
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync vendor ID of 046d (Logitech, Inc), a manufacturer index of 1, and "not
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync remote". Then any USB devices on the host system produced by Logitech,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Inc with a manufacturer index of 1 will be visible to the guest
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync system.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Several filters can select a single device -- for example, a
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync filter which selects all Logitech devices, and one which selects a
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync particular webcam.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>You can <emphasis role="bold">deactivate</emphasis> filters
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync without deleting them by clicking in the checkbox next to the filter
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync name.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <title>Implementation notes for Windows and Linux hosts</title>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>On Windows hosts, a kernel mode device driver provides USB proxy
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync support. It implements both a USB monitor, which allows VirtualBox to
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync capture devices when they are plugged in, and a USB device driver to
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync claim USB devices for a particular virtual machine. As opposed to
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync VirtualBox versions before 1.4.0, system reboots are no longer necessary
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync after installing the driver. Also, you no longer need to replug devices
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync for VirtualBox to claim them.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>On newer Linux hosts, VirtualBox accesses USB devices through
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync special files in the file system. When VirtualBox is installed, these
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync are made available to all users in the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <computeroutput>vboxusers</computeroutput> system group. In order to be
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync able to access USB from guest systems, make sure that you are a member
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync of this group.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>On older Linux hosts, USB devices are accessed using the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <computeroutput>usbfs</computeroutput> file system. Therefore, the user
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync executing VirtualBox needs read and write permission to the USB file
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync system. Most distributions provide a group (e.g.
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <computeroutput>usbusers</computeroutput>) which the VirtualBox user
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync needs to be added to. Also, VirtualBox can only proxy to virtual
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync machines USB devices which are not claimed by a Linux host USB driver.
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync The <computeroutput>Driver=</computeroutput> entry in
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <computeroutput>/proc/bus/usb/devices</computeroutput> will show you
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync which devices are currently claimed. Please refer to <xref
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync linkend="usb_linux" /> also for details about
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Shared folders allow you to easily exchange data between a virtual
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync machine and your host. This feature requires that the VirtualBox Guest
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Additions be installed in a virtual machine and is described in detail in
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Starting with release 3.1, VirtualBox includes experimental support
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync for the Extensible Firmware Interface (EFI), which is a new industry
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync standard intended to eventually replace the legacy BIOS as the primary
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync interface for bootstrapping computers and certain system services
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync later.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>By default, VirtualBox uses the BIOS firmware for virtual machines.
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync To use EFI for a given virtual machine, you can enable EFI in the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync machine's "Settings" dialog (see <xref linkend="settings-motherboard" />).
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Alternatively, use the <computeroutput>VBoxManage</computeroutput> command
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync line interface like this: <screen>VBoxManage modifyvm "VM name" --firmware efi</screen>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync To switch back to using the BIOS, use: <screen>VBoxManage modifyvm "VM name" --firmware bios</screen>One
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync notable user of EFI is Apple's Mac OS X, but recent Linuxes (such as
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Fedora 11) and Windows (starting with Vista) can be booted using EFI as
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync well.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Another possible use of EFI in VirtualBox is development and testing
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync of EFI applications, without booting any OS.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>Note that the VirtualBox EFI support is experimental and will be
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync enhanced as EFI matures and becomes more widespread. While Mac OS X and
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Linux guests are known to work fine, Windows guests are currently unable
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync to boot using EFI.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>EFI provides two distinct video interfaces: GOP (Graphics Output
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Protocol) and UGA (Universal Graphics Adapter). Mac OS X uses GOP, while
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Linux tends to use UGA. VirtualBox provides a configuration option to
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync control the framebuffer size for both interfaces.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>To control GOP, use the following
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <computeroutput>VBoxManage</computeroutput> command: <screen>VBoxManage setextradata "VM name" VBoxInternal2/EfiGopMode N</screen>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync Where N can be one of 0,1,2,3,4 referring to the 640x480, 800x600,
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync 1024x768, 1280x1024, 1440x900 screen resolution respectively.</para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>To change the UGA resolution: <screen>VBoxManage setextradata "VM name" VBoxInternal2/UgaHorizontalResolution 1440
6728a36898fd2be125a28e84d2115d19aa4923edvboxsyncVBoxManage setextradata "VM name" VBoxInternal2/UgaVerticalResolution 900</screen></para>
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync <para>The video mode for both GOP and UGA can only be changed when the
6728a36898fd2be125a28e84d2115d19aa4923edvboxsync VM is powered off and remains persistent until changed.</para>