VirtualBox

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1<?xml version="1.0" encoding="UTF-8"?>
2<!DOCTYPE chapter PUBLIC "-//OASIS//DTD DocBook XML V4.4//EN"
3"http://www.oasis-open.org/docbook/xml/4.4/docbookx.dtd">
4<chapter id="BasicConcepts">
5 <title>Configuring virtual machines</title>
6
7 <para>Whereas <xref linkend="Introduction" /> gave you a quick introduction
8 to VirtualBox and how to get your first virtual machine running, the
9 following chapter describes in detail how to configure virtual
10 machines.</para>
11
12 <para>You have considerable latitude in deciding what virtual hardware will
13 be provided to the guest. The virtual hardware can be used for communicating
14 with the host system or with other guests. For instance, if you provide
15 VirtualBox with the image of a CD-ROM in an ISO file, VirtualBox can present
16 this image to a guest system as if it were a physical CD-ROM. Similarly, you
17 can give a guest system access to the real network via its virtual network
18 card, and, if you so choose, give the host system, other guests, or
19 computers on the Internet access to the guest system.</para>
20
21 <sect1 id="guestossupport">
22 <title>Supported guest operating systems</title>
23
24 <para>Since VirtualBox is designed to provide a generic virtualization
25 environment for x86 systems, it may run operating systems of any kind,
26 even those not listed here. However, the focus is to optimize VirtualBox
27 for the following guest systems:</para>
28
29 <para><glosslist>
30 <glossentry>
31 <glossterm>Windows NT 4.0</glossterm>
32
33 <glossdef>
34 <para>All versions, editions and service packs are fully
35 supported; however, there are some issues with older service
36 packs. We recommend to install service pack 6a. Guest Additions
37 are available with a limited feature set.</para>
38 </glossdef>
39 </glossentry>
40
41 <glossentry>
42 <glossterm>Windows 2000 / XP / Server 2003 / Vista / Server 2008 /
43 7 / 8 / 8.1 / 10 RTM 10240 / Server 2012</glossterm>
44
45 <glossdef>
46 <para>All versions, editions and service packs are fully supported
47 (including 64-bit versions, under the preconditions listed below).
48 Guest Additions are available. Windows 8 and later requires hardware
49 virtualization to be enabled.</para>
50 </glossdef>
51 </glossentry>
52
53 <glossentry>
54 <glossterm>DOS / Windows 3.x / 95 / 98 / ME</glossterm>
55
56 <glossdef>
57 <para>Limited testing has been performed. Use beyond legacy
58 installation mechanisms not recommended. No Guest Additions
59 available.</para>
60 </glossdef>
61 </glossentry>
62
63 <glossentry>
64 <glossterm>Linux 2.4</glossterm>
65
66 <glossdef>
67 <para>Limited support.</para>
68 </glossdef>
69 </glossentry>
70
71 <glossentry>
72 <glossterm>Linux 2.6</glossterm>
73
74 <glossdef>
75 <para>All versions/editions are fully supported (32 bits and 64
76 bits). Guest Additions are available.</para>
77
78 <para>We strongly recommend using a Linux kernel version 2.6.13 or
79 higher for better performance.<note>
80 <para>Certain Linux kernel releases have bugs that prevent
81 them from executing in a virtual environment; please see <xref
82 linkend="ts_linux-buggy" /> for details.</para>
83 </note></para>
84 </glossdef>
85 </glossentry>
86
87 <glossentry>
88 <glossterm>Linux 3.x and later</glossterm>
89
90 <glossdef>
91 <para>All versions/editions are fully supported (32 bits and 64
92 bits). Guest Additions are available.</para>
93 </glossdef>
94 </glossentry>
95
96 <glossentry>
97 <glossterm>Solaris 10 (u6 and higher), Solaris 11 (including Solaris
98 11 Express)</glossterm>
99
100 <glossdef>
101 <para>Fully supported (64 bits, prior to Solaris 11 11/11 also 32 bits).
102 Guest Additions are available.</para>
103 </glossdef>
104 </glossentry>
105
106 <glossentry>
107 <glossterm>FreeBSD</glossterm>
108
109 <glossdef>
110 <para>Requires hardware virtualization to be enabled. Limited
111 support. Guest Additions are not available yet.</para>
112 </glossdef>
113 </glossentry>
114
115 <glossentry>
116 <glossterm>OpenBSD</glossterm>
117
118 <glossdef>
119 <para>Requires hardware virtualization to be enabled. Versions 3.7
120 and later are supported. Guest Additions are not available
121 yet.</para>
122 </glossdef>
123 </glossentry>
124
125 <glossentry>
126 <glossterm>OS/2 Warp 4.5</glossterm>
127
128 <glossdef>
129 <para>Requires hardware virtualization to be enabled. We
130 officially support MCP2 only; other OS/2 versions may or may not
131 work. Guest Additions are available with a limited feature
132 set.<footnote>
133 <para>See <xref linkend="KnownIssues" />.</para>
134 </footnote></para>
135 </glossdef>
136 </glossentry>
137
138 <glossentry>
139 <glossterm>Mac OS X</glossterm>
140
141 <glossdef>
142 <para>VirtualBox 3.2 added experimental support for Mac OS X
143 guests, but this comes with restrictions. Please see the following
144 section as well as <xref linkend="KnownIssues" />.</para>
145 </glossdef>
146 </glossentry>
147 </glosslist></para>
148
149 <sect2 id="intro-macosxguests">
150 <title>Mac OS X guests</title>
151
152 <para>Starting with version 3.2, VirtualBox has experimental support for
153 Mac OS X guests. This allows you to install and execute unmodified
154 versions of Mac OS X on supported host hardware.</para>
155
156 <para>Whereas competing solutions perform modifications to the Mac OS X
157 install DVDs (e.g. different boot loader and replaced files), VirtualBox
158 is the first product to provide the modern PC architecture expected by
159 OS X without requiring any "hacks".</para>
160
161 <para>You should be aware of a number of <emphasis role="bold">important
162 issues</emphasis> before attempting to install a Mac OS X guest:<orderedlist>
163 <listitem>
164 <para>Mac OS X is commercial, licensed software and contains
165 <emphasis role="bold">both license and technical restrictions</emphasis>
166 that limit its use to certain hardware and usage scenarios. It is
167 important that you understand and obey these restrictions.</para>
168
169 <para>In particular, for most versions of Mac OS X, Apple prohibits
170 installing them on non-Apple hardware.</para>
171
172 <para>These license restrictions are also enforced on a technical
173 level. Mac OS X verifies whether it is running on Apple hardware,
174 and most DVDs that come with Apple hardware even check for an
175 exact model. These restrictions are <emphasis>not</emphasis>
176 circumvented by VirtualBox and continue to apply.</para>
177 </listitem>
178
179 <listitem>
180 <para>Only <emphasis role="bold">CPUs</emphasis> known and tested
181 by Apple are supported. As a result, if your Intel CPU is newer
182 than the build of Mac OS X, or if you have a non-Intel CPU, it will
183 most likely panic during bootup with an "Unsupported CPU"
184 exception. It is generally best to use the Mac OS X DVD that came
185 with your Apple hardware.</para>
186 </listitem>
187
188 <listitem>
189 <para>The Mac OS X installer expects the harddisk to be
190 <emphasis role="bold">partitioned</emphasis> so when it does not
191 offer a selection, you have to launch the Disk Utility from the
192 "Tools" menu and partition the hard disk. Then close the Disk
193 Utility and proceed with the installation.</para>
194 </listitem>
195
196 <listitem>
197 <para>In addition, as Mac OS X support in VirtualBox is currently
198 still experimental, please refer also to <xref linkend="KnownIssues" />.</para>
199 </listitem>
200 </orderedlist></para>
201 </sect2>
202
203 <sect2 id="intro-64bitguests">
204 <title>64-bit guests</title>
205
206 <para>VirtualBox supports 64-bit guest operating systems, even on 32-bit
207 host operating systems,<footnote>
208 <para>64-bit guest support was added with VirtualBox 2.0; support
209 for 64-bit guests on 32-bit hosts was added with VirtualBox
210 2.1.</para>
211 </footnote> provided that the following conditions are
212 met:<orderedlist>
213 <listitem>
214 <para>You need a 64-bit processor with hardware virtualization
215 support (see <xref linkend="hwvirt" />).</para>
216 </listitem>
217
218 <listitem>
219 <para>You must enable hardware virtualization for the particular
220 VM for which you want 64-bit support; software virtualization is
221 not supported for 64-bit VMs.</para>
222 </listitem>
223
224 <listitem>
225 <para>If you want to use 64-bit guest support on a 32-bit host
226 operating system, you must also select a 64-bit operating system
227 for the particular VM. Since supporting 64 bits on 32-bit hosts
228 incurs additional overhead, VirtualBox only enables this support
229 upon explicit request.</para>
230
231 <para>On 64-bit hosts (which typically come with hardware
232 virtualization support), 64-bit guest operating systems are always
233 supported regardless of settings, so you can simply install a
234 64-bit operating system in the guest.</para>
235 </listitem>
236 </orderedlist></para>
237
238 <para><warning>
239 <para>On any host, you should enable the <emphasis role="bold">I/O
240 APIC</emphasis> for virtual machines that you intend to use in
241 64-bit mode. This is especially true for 64-bit Windows VMs. See
242 <xref linkend="settings-general-advanced" />. In addition, for
243 64-bit Windows guests, you should make sure that the VM uses the
244 <emphasis role="bold">Intel networking device</emphasis>, since
245 there is no 64-bit driver support for the AMD PCNet card; see <xref
246 linkend="nichardware" />.</para>
247 </warning></para>
248
249 <para>If you use the "Create VM" wizard of the VirtualBox graphical user
250 interface (see <xref linkend="gui-createvm" />), VirtualBox will
251 automatically use the correct settings for each selected 64-bit
252 operating system type.</para>
253 </sect2>
254 </sect1>
255
256 <sect1>
257 <title>Emulated hardware</title>
258
259 <para>VirtualBox virtualizes nearly all hardware of the host. Depending on
260 a VM's configuration, the guest will see the following virtual
261 hardware:<itemizedlist>
262 <listitem>
263 <para><emphasis role="bold">Input devices.</emphasis> By default,
264 VirtualBox emulates a standard PS/2 keyboard and mouse. These
265 devices are supported by almost all past and present operating
266 systems.</para>
267
268 <para>In addition, VirtualBox can provide virtual USB input devices
269 to avoid having to capture mouse and keyboard, as described in <xref
270 linkend="keyb_mouse_normal" />.</para>
271 </listitem>
272
273 <listitem>
274 <para><emphasis role="bold">Graphics.</emphasis> The VirtualBox
275 graphics device (sometimes referred to as VGA device) is, unlike
276 nearly all other emulated devices, not based on any physical
277 counterpart. It is a simple, synthetic device which provides
278 compatibility with standard VGA and several extended registers used
279 by the VESA BIOS Extensions (VBE).</para>
280 </listitem>
281
282 <listitem>
283 <para><emphasis role="bold">Storage.</emphasis> VirtualBox currently
284 emulates the standard ATA interface found on Intel PIIX3/PIIX4
285 chips, the SATA (AHCI) interface, and two SCSI adapters (LSI Logic
286 and BusLogic); see <xref linkend="harddiskcontrollers" /> for
287 details. Whereas providing one of these would be enough for
288 VirtualBox by itself, this multitude of storage adapters is required
289 for compatibility with other hypervisors. Windows is particularly
290 picky about its boot devices, and migrating VMs between hypervisors
291 is very difficult or impossible if the storage controllers are
292 different.</para>
293 </listitem>
294
295 <listitem>
296 <para><emphasis role="bold">Networking.</emphasis> See <xref
297 linkend="nichardware" />.</para>
298 </listitem>
299
300 <listitem>
301 <para><emphasis role="bold">USB.</emphasis> VirtualBox emulates three
302 USB host controllers: xHCI, EHCI, and OHCI. While xHCI handles all USB
303 transfer speeds, only guest operating systems released approximately
304 after 2011 support xHCI. Note that for Windows 7 guests, 3rd party
305 drivers must be installed for xHCI support.</para>
306 <para>
307 Older operating systems typically support OHCI and EHCI. The two
308 controllers are needed because OHCI only handles USB low- and full-speed
309 devices (both USB 1.x and 2.0), while EHCI only handles high-speed
310 devices (USB 2.0 only).</para>
311 <para>
312 The emulated USB controllers do not
313 communicate directly with devices on the host but rather with a
314 virtual USB layer which abstracts the USB protocol and allows the
315 use of remote USB devices.</para>
316 </listitem>
317
318 <listitem>
319 <para><emphasis role="bold">Audio.</emphasis> See <xref
320 linkend="settings-audio" />.</para>
321 </listitem>
322 </itemizedlist></para>
323 </sect1>
324
325 <sect1 id="generalsettings">
326 <title>General settings</title>
327
328 <para>In the Settings window, under "General", you can configure the most
329 fundamental aspects of the virtual machine such as memory and essential
330 hardware. There are three tabs, "Basic", "Advanced" and
331 "Description".</para>
332
333 <sect2>
334 <title>"Basic" tab</title>
335
336 <para>Under the "Basic" tab of the "General" settings category, you can
337 find these settings:</para>
338
339 <glosslist>
340 <glossentry>
341 <glossterm>Name</glossterm>
342
343 <glossdef>
344 <para>The name under which the VM is shown in the list of VMs in
345 the main window. Under this name, VirtualBox also saves the VM's
346 configuration files. By changing the name, VirtualBox renames
347 these files as well. As a result, you can only use characters
348 which are allowed in your host operating system's file
349 names.</para>
350
351 <para>Note that internally, VirtualBox uses unique identifiers
352 (UUIDs) to identify virtual machines. You can display these with
353 <computeroutput>VBoxManage</computeroutput>.</para>
354 </glossdef>
355 </glossentry>
356
357 <glossentry>
358 <glossterm>Operating system / version</glossterm>
359
360 <glossdef>
361 <para>The type of the guest operating system that is (or will be)
362 installed in the VM. This is the same setting that was specified
363 in the "New Virtual Machine" wizard, as described in <xref
364 linkend="gui-createvm" />.</para>
365
366 <para>Whereas the default settings of a newly created VM depend on
367 the selected operating system type, changing the type later has no
368 effect on VM settings; this value is then purely informational and
369 decorative.</para>
370 </glossdef>
371 </glossentry>
372 </glosslist>
373 </sect2>
374
375 <sect2 id="settings-general-advanced">
376 <title>"Advanced" tab</title>
377
378 <para><glosslist>
379 <glossentry>
380 <glossterm>Snapshot Folder</glossterm>
381
382 <glossdef>
383 <para>By default, VirtualBox saves snapshot data together with
384 your other VirtualBox configuration data; see <xref
385 linkend="vboxconfigdata" />. With this setting, you can specify
386 any other folder for each VM.</para>
387 </glossdef>
388 </glossentry>
389
390 <glossentry>
391 <glossterm>Shared Clipboard</glossterm>
392
393 <glossdef>
394 <para>You can select here whether the clipboard of the guest
395 operating system should be shared with that of your host. If you
396 select "Bidirectional", then VirtualBox will always make sure
397 that both clipboards contain the same data. If you select "Host
398 to guest" or "Guest to host", then VirtualBox will only ever
399 copy clipboard data in one direction.</para>
400
401 <para>Clipboard sharing requires that the VirtualBox Guest
402 Additions be installed. As a result, this setting has no effect
403 otherwise; see <xref linkend="guestadditions" /> for
404 details.</para>
405
406 <para>The shared clipboard is disabled by default. See
407 <xref linkend="security_clipboard"/> for an explanation. This
408 setting can be changed at any time using the "Shared Clipboard"
409 menu item in the "Devices" menu of the virtual machine.</para>
410 </glossdef>
411 </glossentry>
412
413 <glossentry>
414 <glossterm>Drag and Drop</glossterm>
415 <glossdef>
416 <para>This setting allows to enable support for drag and drop: Select
417 an object (e.g. a file) from the host or guest and directly copy
418 or open it on the guest or host. Multiple per-VM drag and drop modes
419 allow restricting access in either direction.</para>
420
421 <para>For drag and drop to work the Guest Additions need to be
422 installed on the guest.</para>
423
424 <para><note><para>Drag and drop is disabled by default. This setting can be
425 changed at any time using the "Drag and Drop" menu item in the
426 "Devices" menu of the virtual machine.</para></note></para>
427
428 <para>See <xref linkend="guestadd-dnd"/> for more information.
429 <footnote><para>Experimental support for drag and drop was added
430 with VirtualBox 4.2.</para></footnote></para>
431 </glossdef>
432 </glossentry>
433
434 </glosslist></para>
435 </sect2>
436
437 <sect2>
438 <title>"Description" tab</title>
439
440 <para>Here you can enter any description for your virtual machine, if
441 you want. This has no effect on the functionality of the machine, but
442 you may find this space useful to note down things like the
443 configuration of a virtual machine and the software that has been
444 installed into it.</para>
445 <para>To insert a line break into the description text field, press
446 <emphasis>Shift+Enter</emphasis>.</para>
447 </sect2>
448 </sect1>
449
450 <sect1 id="settings-system">
451 <title>System settings</title>
452
453 <para>The "System" category groups various settings that are related to
454 the basic hardware that is presented to the virtual machine.<note>
455 <para>As the activation mechanism of Microsoft Windows is sensitive to
456 hardware changes, if you are changing hardware settings for a Windows
457 guest, some of these changes may trigger a request for another
458 activation with Microsoft.</para>
459 </note></para>
460
461 <sect2 id="settings-motherboard">
462 <title>"Motherboard" tab</title>
463
464 <para>On the "Motherboard" tab, you can influence virtual hardware that
465 would normally be on the motherboard of a real computer.<glosslist>
466 <glossentry>
467 <glossterm>Base memory</glossterm>
468
469 <glossdef>
470 <para>This sets the amount of RAM that is allocated and given to
471 the VM when it is running. The specified amount of memory will
472 be requested from the host operating system, so it must be
473 available or made available as free memory on the host when
474 attempting to start the VM and will not be available to the host
475 while the VM is running. This is the same setting that was
476 specified in the "New Virtual Machine" wizard, as described with
477 guidelines under <xref linkend="gui-createvm" /> above.</para>
478
479 <para>Generally, it is possible to change the memory size after
480 installing the guest operating system (provided you do not
481 reduce the memory to an amount where the operating system would
482 no longer boot).</para>
483 </glossdef>
484 </glossentry>
485
486 <glossentry>
487 <glossterm>Boot order</glossterm>
488
489 <glossdef>
490 <para>This setting determines the order in which the guest
491 operating system will attempt to boot from the various virtual
492 boot devices. Analogous to a real PC's BIOS setting, VirtualBox
493 can tell a guest OS to start from the virtual floppy, the
494 virtual CD/DVD drive, the virtual hard drive (each of these as
495 defined by the other VM settings), the network, or none of
496 these.</para>
497
498 <para>If you select "Network", the VM will attempt to boot from
499 a network via the PXE mechanism. This needs to be configured in
500 detail on the command line; please see <xref
501 linkend="vboxmanage-modifyvm" />.</para>
502 </glossdef>
503 </glossentry>
504
505 <glossentry>
506 <glossterm>Chipset</glossterm>
507
508 <glossdef>
509 <para>Here you can select which chipset will be presented to the
510 virtual machine. Before VirtualBox 4.0, PIIX3 was the only
511 available option here. For modern guest operating systems such
512 as Mac OS X, that old chipset is no longer well supported. As a
513 result, VirtualBox 4.0 introduced an emulation of the more
514 modern ICH9 chipset, which supports PCI express, three PCI
515 buses, PCI-to-PCI bridges and Message Signaled Interrupts
516 (MSI). This allows modern operating systems to address more PCI
517 devices and no longer requires IRQ sharing. Using the ICH9 chipset
518 it is also possible to configure up to 36 network cards (up to 8
519 network adapters with PIIX3). Note that the ICH9 support is
520 experimental and not recommended for guest operating systems which
521 do not require it.</para>
522 </glossdef>
523 </glossentry>
524
525 <glossentry>
526 <glossterm>Pointing Device</glossterm>
527
528 <glossdef>
529 <para>The default virtual pointing devices for older guests is the
530 traditional PS/2 mouse. If set to <emphasis>USB tablet</emphasis>,
531 VirtualBox reports to the virtual machine that a USB tablet
532 device is present and communicates mouse events to
533 the virtual machine through this device. The third setting is
534 a <emphasis>USB Multi-Touch Tablet</emphasis> which is suited
535 for recent Windows guests.</para>
536
537 <para>Using the virtual USB tablet has the advantage that
538 movements are reported in absolute coordinates (instead of as
539 relative position changes), which allows VirtualBox to translate
540 mouse events over the VM window into tablet events without
541 having to "capture" the mouse in the guest as described in <xref
542 linkend="keyb_mouse_normal" />. This makes using the VM less
543 tedious even if Guest Additions are not installed.<footnote>
544 <para>The virtual USB tablet was added with VirtualBox 3.2.
545 Depending on the guest operating system selected, this is
546 now enabled by default for new virtual machines.</para>
547 </footnote></para>
548 </glossdef>
549 </glossentry>
550 <glossentry>
551 <glossterm>Enable I/O APIC</glossterm>
552
553 <glossdef>
554 <para>Advanced Programmable Interrupt Controllers (APICs) are a
555 newer x86 hardware feature that have replaced old-style
556 Programmable Interrupt Controllers (PICs) in recent years. With
557 an I/O APIC, operating systems can use more than 16 interrupt
558 requests (IRQs) and therefore avoid IRQ sharing for improved
559 reliability.<note>
560 <para>Enabling the I/O APIC is <emphasis>required</emphasis>
561 for 64-bit guest operating systems, especially Windows
562 Vista; it is also required if you want to use more than one
563 virtual CPU in a virtual machine.</para>
564 </note></para>
565
566 <para>However, software support for I/O APICs has been
567 unreliable with some operating systems other than Windows. Also,
568 the use of an I/O APIC slightly increases the overhead of
569 virtualization and therefore slows down the guest OS a
570 little.<warning>
571 <para>All Windows operating systems starting with Windows
572 2000 install different kernels depending on whether an I/O
573 APIC is available. As with ACPI, the I/O APIC therefore
574 <emphasis>must not be turned off after
575 installation</emphasis> of a Windows guest OS. Turning it on
576 after installation will have no effect however.</para>
577 </warning></para>
578 </glossdef>
579 </glossentry>
580
581 <glossentry>
582 <glossterm>Enable EFI</glossterm>
583
584 <glossdef>
585 <para>This enables Extensible Firmware Interface (EFI), which
586 replaces the legacy BIOS and may be useful for certain
587 advanced use cases. Please refer to <xref linkend="efi" /> for
588 details.</para>
589 </glossdef>
590 </glossentry>
591
592 <glossentry>
593 <glossterm>Hardware clock in UTC time</glossterm>
594
595 <glossdef>
596 <para>If checked, VirtualBox will report the system time in UTC
597 format to the guest instead of local (host) time. This affects
598 how the virtual real-time clock (RTC) operates and may be useful
599 for Unix-like guest operating systems, which typically expect
600 the hardware clock to be set to UTC.</para>
601 </glossdef>
602 </glossentry>
603
604 </glosslist></para>
605
606 <para>In addition, you can turn off the <emphasis role="bold">Advanced
607 Configuration and Power Interface (ACPI)</emphasis> which VirtualBox
608 presents to the guest operating system by default. ACPI is the current
609 industry standard to allow operating systems to recognize hardware,
610 configure motherboards and other devices and manage power. As all modern
611 PCs contain this feature and Windows and Linux have been supporting it
612 for years, it is also enabled by default in VirtualBox. It can only be
613 turned off on the command line; see <xref
614 linkend="vboxmanage-modifyvm" />.<warning>
615 <para>All Windows operating systems starting with Windows 2000
616 install different kernels depending on whether ACPI is available, so
617 ACPI <emphasis>must not be turned off</emphasis> after installation
618 of a Windows guest OS. Turning it on after installation will have no
619 effect however.</para>
620 </warning></para>
621 </sect2>
622
623 <sect2 id="settings-processor">
624 <title>"Processor" tab</title>
625
626 <para>On the "Processor" tab, you can set how many virtual <emphasis
627 role="bold">CPU cores</emphasis> the guest operating systems should see.
628 Starting with version 3.0, VirtualBox supports symmetrical
629 multiprocessing (SMP) and can present up to 32 virtual CPU cores to each
630 virtual machine.</para>
631
632 <para>You should not, however, configure virtual machines to use more
633 CPU cores than you have available physically (real cores, no hyperthreads).</para>
634
635 <para>On this tab you can also set the <emphasis role="bold">"CPU execution
636 cap"</emphasis>. This setting
637 limits the amount of time a host CPU spends to emulate a virtual CPU.
638 The default setting is 100% meaning that there is no limitation. A setting
639 of 50% implies a single virtual CPU can use up to 50% of a single host
640 CPU. Note that limiting the execution time of the virtual CPUs may induce
641 guest timing problems.</para>
642
643 <para>In addition, the <emphasis role="bold">"Enable PAE/NX"</emphasis>
644 setting determines whether the PAE and NX capabilities of the host CPU
645 will be exposed to the virtual machine. PAE stands for "Physical Address
646 Extension". Normally, if enabled and supported by the operating system,
647 then even a 32-bit x86 CPU can access more than 4 GB of RAM. This is
648 made possible by adding another 4 bits to memory addresses, so that with
649 36 bits, up to 64 GB can be addressed. Some operating systems (such as
650 Ubuntu Server) require PAE support from the CPU and cannot be run in a
651 virtual machine without it.</para>
652
653 <para>With virtual machines running modern server operating systems,
654 VirtualBox also supports CPU hot-plugging. For details about this,
655 please refer to <xref linkend="cpuhotplug" />.</para>
656 </sect2>
657
658 <sect2>
659 <title>"Acceleration" tab</title>
660
661 <para>On this page, you can determine whether and how VirtualBox should
662 use hardware virtualization extensions that your host CPU may support.
663 This is the case with most CPUs built after 2006.</para>
664
665 <para>You can select for each virtual machine individually whether
666 VirtualBox should use software or hardware virtualization.<footnote>
667 <para>Prior to VirtualBox version 2.2, software virtualization was
668 the default; starting with version 2.2, VirtualBox will enable
669 hardware virtualization by default for new virtual machines that you
670 create. (Existing virtual machines are not automatically changed for
671 compatibility reasons, and the default can of course be changed for
672 each virtual machine.)</para>
673 </footnote></para>
674
675 <para>In most cases, the default settings will be fine; VirtualBox will
676 have picked sensible defaults depending on the operating system that you
677 selected when you created the virtual machine. In certain situations,
678 however, you may want to change these preconfigured defaults.</para>
679
680 <para>Advanced users may be interested in technical details about
681 software vs. hardware virtualization; please see <xref
682 linkend="hwvirt" />.</para>
683
684 <para>If your host's CPU supports the <emphasis role="bold">nested
685 paging</emphasis> (AMD-V) or <emphasis role="bold">EPT</emphasis> (Intel
686 VT-x) features, then you can expect a significant performance increase
687 by enabling nested paging in addition to hardware virtualization. For
688 technical details, see <xref linkend="nestedpaging" />.</para>
689
690 <para>Starting with version 5.0, VirtualBox provides paravirtualization
691 interfaces to improve time-keeping accuracy and performance of guest
692 operating systems. The options available are documented under the
693 <computeroutput>paravirtprovider</computeroutput> option
694 in <xref linkend="vboxmanage-modifyvm" />. For further details on
695 the paravirtualization providers, please refer to
696 <xref linkend="gimproviders" />.</para>
697 </sect2>
698 </sect1>
699
700 <sect1 id="settings-display">
701 <title>Display settings</title>
702
703 <glosslist>
704 <glossentry>
705 <glossterm>Video memory size</glossterm>
706
707 <glossdef>
708 <para>This sets the size of the memory provided by the virtual
709 graphics card available to the guest, in MB. As with the main
710 memory, the specified amount will be allocated from the host's
711 resident memory. Based on the amount of video memory, higher
712 resolutions and color depths may be available.</para>
713 <para>The GUI will show a warning if the amount of video memory
714 is too small to be able to switch the VM into full screen mode.
715 The minimum value depends on the number of virtual monitors, the
716 screen resolution and the color depth of the host display as well
717 as of the activation of <emphasis>3D acceleration</emphasis> and
718 <emphasis>2D video acceleration</emphasis>. A rough estimate
719 is (<emphasis>color depth</emphasis> / 8) x
720 <emphasis>vertical pixels</emphasis> x
721 <emphasis>horizontal pixels</emphasis> x
722 <emphasis>number of screens</emphasis> = <emphasis>number of bytes</emphasis>.
723 Like said above, there might be extra memory required for any
724 activated display acceleration setting.</para>
725 </glossdef>
726 </glossentry>
727
728 <glossentry>
729 <glossterm>Monitor count</glossterm>
730
731 <glossdef>
732 <para>With this setting VirtualBox can provide more than one virtual
733 monitor to a virtual machine. If a guest operating system (such as
734 Windows) supports multiple attached monitors, VirtualBox can pretend
735 that multiple virtual monitors are present.<footnote>
736 <para>Multiple monitor support was added with VirtualBox
737 3.2.</para>
738 </footnote> Up to 8 such virtual monitors are supported.</para>
739
740 <para>The output of the multiple monitors will be displayed on the
741 host in multiple VM windows which are running side by side.</para>
742
743 <para>However, in full screen and seamless mode, they will use the
744 available physical monitors attached to the host. As a result, for
745 full screen and seamless modes to work with multiple monitors, you
746 will need at least as many physical monitors as you have virtual
747 monitors configured, or VirtualBox will report an error. You can
748 configure the relationship between guest and host monitors using the
749 view menu by pressing Host key + Home when you are in full screen or
750 seamless mode.</para>
751
752 <para>Please see <xref linkend="KnownIssues" /> also.</para>
753 </glossdef>
754 </glossentry>
755
756 <glossentry>
757 <glossterm>Enable 3D acceleration</glossterm>
758
759 <glossdef>
760 <para>If a virtual machine has Guest Additions installed, you can
761 select here whether the guest should support accelerated 3D
762 graphics. Please refer to <xref linkend="guestadd-3d" /> for
763 details.</para>
764 </glossdef>
765 </glossentry>
766
767 <glossentry>
768 <glossterm>Enable 2D video acceleration</glossterm>
769
770 <glossdef>
771 <para>If a virtual machine with Microsoft Windows has Guest
772 Additions installed, you can select here whether the guest should
773 support accelerated 2D video graphics. Please refer to <xref
774 linkend="guestadd-2d" /> for details.</para>
775 </glossdef>
776 </glossentry>
777
778 <glossentry>
779 <glossterm>Remote display</glossterm>
780
781 <glossdef>
782 <para>Under the "Remote display" tab, if the VirtualBox Remote
783 Display Extension (VRDE) is installed, you can enable the VRDP server
784 that is built into VirtualBox. This allows you to connect to the
785 console of the virtual machine remotely with any standard RDP viewer,
786 such as <computeroutput>mstsc.exe</computeroutput> that comes with
787 Microsoft Windows. On Linux and Solaris systems you can use the
788 standard open-source <computeroutput>rdesktop</computeroutput>
789 program. These features are described in detail in
790 <xref linkend="vrde" />.</para>
791 </glossdef>
792 </glossentry>
793
794 <glossentry>
795 <glossterm>Video Capture</glossterm>
796
797 <glossdef>
798 <para>Under the "Video Capture" tab you can enable video capturing
799 for this VM. Note that this feature can also be enabled/disabled
800 while the VM is executed.</para>
801 </glossdef>
802 </glossentry>
803 </glosslist>
804 </sect1>
805
806 <sect1 id="settings-storage">
807 <title>Storage settings</title>
808
809 <para>The "Storage" category in the VM settings allows you to connect
810 virtual hard disk, CD/DVD and floppy images and drives to your virtual
811 machine.</para>
812
813 <para>In a real PC, so-called "storage controllers" connect physical disk
814 drives to the rest of the computer. Similarly, VirtualBox presents virtual
815 storage controllers to a virtual machine. Under each controller, the
816 virtual devices (hard disks, CD/DVD or floppy drives) attached to the
817 controller are shown.<note>
818 <para>This section can only give you a quick introduction to the
819 VirtualBox storage settings. Since VirtualBox gives you an enormous
820 wealth of options in this area, we have dedicated an entire chapter of
821 this User Manual to explaining all the details: please see <xref
822 linkend="storage" />.</para>
823 </note></para>
824
825 <para>If you have used the "Create VM" wizard to create a machine, you
826 will normally see something like the following:</para>
827
828 <para><mediaobject>
829 <imageobject>
830 <imagedata align="center" fileref="images/vm-settings-harddisk.png"
831 width="10cm" />
832 </imageobject>
833 </mediaobject></para>
834
835 <para>Depending on the guest operating system type that you selected when
836 you created the VM, the typical layout of storage devices in a new VM is
837 as follows:<itemizedlist>
838 <listitem>
839 <para>You will see an <emphasis role="bold">IDE
840 controller,</emphasis> to which a virtual CD/DVD drive has been
841 attached (to the "secondary master" port of the IDE
842 controller).</para>
843 </listitem>
844
845 <listitem>
846 <para>You will also see a <emphasis role="bold">SATA
847 controller,</emphasis> which is a more modern type of storage
848 controller for higher hard disk data throughput, to which the
849 virtual hard disks are attached. Initially you will normally have
850 one such virtual disk, but as you can see in the above screenshot,
851 you can have more than one, each represented by a disk image file
852 (VDI files, in this case).</para>
853 </listitem>
854 </itemizedlist></para>
855
856 <para>If you created your VM with an older version of VirtualBox, the
857 default storage layout may differ. You might then only have an IDE
858 controller to which both the CD/DVD drive and the hard disks have been
859 attached. This might also apply if you selected an older operating system
860 type when you created the VM. Since older operating systems do not support
861 SATA without additional drivers, VirtualBox will make sure that no such
862 devices are present initially. Please see <xref
863 linkend="harddiskcontrollers" /> for additional information.</para>
864
865 <para>VirtualBox also provides a <emphasis role="bold">floppy
866 controller</emphasis>, which is special: you cannot add devices other than
867 floppy drives to it. Virtual floppy drives, like virtual CD/DVD drives,
868 can be connected to either a host floppy drive (if you have one) or a disk
869 image, which in this case must be in RAW format.</para>
870
871 <para>You can modify these media attachments freely. For example, if you
872 wish to copy some files from another virtual disk that you created, you
873 can connect that disk as a second hard disk, as in the above screenshot.
874 You could also add a second virtual CD/DVD drive, or change where these
875 items are attached. The following options are available:<itemizedlist>
876 <listitem>
877 <para>To <emphasis role="bold">add another virtual hard disk, or a
878 CD/DVD or floppy drive,</emphasis> select the storage controller to
879 which it should be added (IDE, SATA, SCSI, SAS, floppy controller)
880 and then click on the "add disk" button below the tree. You can then
881 either select "Add CD/DVD device" or "Add Hard Disk". (If you
882 clicked on a floppy controller, you can add a floppy drive instead.)
883 Alternatively, right-click on the storage controller and select a
884 menu item there.</para>
885
886 <para>On the right part of the window, you can then set the
887 following:<orderedlist>
888 <listitem>
889 <para>You can then select to which <emphasis
890 role="bold">device slot</emphasis> of the controller the
891 virtual disk should be connected to. IDE controllers have four
892 slots which have traditionally been called "primary master",
893 "primary slave", "secondary master" and "secondary slave". By
894 contrast, SATA and SCSI controllers offer you up to 30 slots
895 to which virtual devices can be attached.</para>
896 </listitem>
897
898 <listitem>
899 <para>You can select which <emphasis role="bold">image
900 file</emphasis> to use.<itemizedlist>
901 <listitem>
902 <para>For virtual hard disks, a button with a drop-down
903 list appears on the right, offering you to either select
904 a <emphasis role="bold">virtual hard disk
905 file</emphasis> using a standard file dialog or to
906 <emphasis role="bold">create a new hard disk</emphasis>
907 (image file), which will bring up the "Create new disk"
908 wizard, which was described in <xref
909 linkend="gui-createvm" />.</para>
910
911 <para>For details on the image file types that are
912 supported, please see <xref
913 linkend="vdidetails" />.</para>
914 </listitem>
915
916 <listitem>
917 <para>For virtual CD/DVD drives, the image files will
918 typically be in the standard ISO format instead. Most
919 commonly, you will select this option when installing an
920 operating system from an ISO file that you have obtained
921 from the Internet. For example, most Linux distributions
922 are available in this way.</para>
923
924 <para>For virtual CD/DVD drives, the following
925 additional options are available:</para>
926
927 <para><itemizedlist>
928 <listitem>
929 <para>If you select <emphasis role="bold">"Host
930 drive"</emphasis> from the list, then the physical
931 device of the host computer is connected to the VM,
932 so that the guest operating system can read from and
933 write to your physical device. This is, for
934 instance, useful if you want to install Windows from
935 a real installation CD. In this case, select your
936 host drive from the drop-down list presented.</para>
937
938 <para>If you want to write (burn) CDs or DVDs using
939 the host drive, you need to also enable the
940 <emphasis role="bold">"Passthrough"</emphasis>
941 option; see <xref linkend="storage-cds" />.</para>
942 </listitem>
943
944 <listitem>
945 <para>If you select <emphasis role="bold">"Remove
946 disk from virtual drive",</emphasis> VirtualBox will
947 present an empty CD/DVD drive to the guest into
948 which no media has been inserted.</para>
949 </listitem>
950 </itemizedlist></para>
951 </listitem>
952 </itemizedlist></para>
953 </listitem>
954 </orderedlist></para>
955 </listitem>
956
957 <listitem>
958 <para>To <emphasis role="bold">remove an attachment,</emphasis>
959 select it and click on the "remove" icon at the bottom (or
960 right-click on it and select the menu item).</para>
961 </listitem>
962 </itemizedlist></para>
963
964 <para>Removable media (CD/DVDs and floppies) can be changed while the
965 guest is running. Since the "Settings" dialog is not available at that
966 time, you can also access these settings from the "Devices" menu of your
967 virtual machine window.</para>
968 </sect1>
969
970 <sect1 id="settings-audio">
971 <title>Audio settings</title>
972
973 <para>The "Audio" section in a virtual machine's Settings window
974 determines whether the VM will see a sound card connected, and whether the
975 audio output should be heard on the host system.</para>
976
977 <para>If audio is enabled for a guest, you can choose between the
978 emulation of an Intel AC'97 controller, an Intel HD Audio
979 controller<footnote>
980 <para>Intel HD Audio support was added with VirtualBox 4.0 because
981 Windows 7 and later (as well as 64-bit Windows Vista) do not support
982 the Intel AC'97 controller out of the box.</para>
983 </footnote> or a SoundBlaster 16 card. In any case, you can select what
984 audio driver VirtualBox will use on the host.</para>
985
986 <para>On a Linux host, depending on your host configuration, you can also
987 select between the OSS, ALSA or the PulseAudio subsystem. On newer Linux
988 distributions, the PulseAudio subsystem should be preferred.</para>
989
990 <para>Since VirtualBox 5.0 only OSS is supported on Solaris hosts - the "Solaris Audio"
991 audio backend is no longer supported on Solaris hosts.</para>
992 </sect1>
993
994 <sect1 id="settings-network">
995 <title>Network settings</title>
996
997 <para>The "Network" section in a virtual machine's Settings window allows
998 you to configure how VirtualBox presents virtual network cards to your VM,
999 and how they operate.</para>
1000
1001 <para>When you first create a virtual machine, VirtualBox by default
1002 enables one virtual network card and selects the "Network Address
1003 Translation" (NAT) mode for it. This way the guest can connect to the
1004 outside world using the host's networking and the outside world can
1005 connect to services on the guest which you choose to make visible outside
1006 of the virtual machine.</para>
1007
1008 <para>This default setup is good for probably 95% of VirtualBox users.
1009 However, VirtualBox is extremely flexible in how it can virtualize
1010 networking. It supports many virtual network cards per virtual machine,
1011 the first four of which can be configured in detail in the Manager window.
1012 Additional network cards can be configured on the command line with
1013 VBoxManage. </para>
1014
1015 <para>Because of the vast array of options available, we have dedicated an
1016 entire chapter of this manual to discussing networking configuration;
1017 please see <xref linkend="networkingdetails" />.</para>
1018 </sect1>
1019
1020 <sect1 id="serialports">
1021 <title>Serial ports</title>
1022
1023 <para>VirtualBox fully supports virtual serial ports in a virtual machine
1024 in an easy-to-use manner.<footnote>
1025 <para>Serial port support was added with VirtualBox 1.5.</para>
1026 </footnote></para>
1027
1028 <para>Ever since the original IBM PC, personal computers have been
1029 equipped with one or two serial ports (also called COM ports by DOS and
1030 Windows). Serial ports were commonly used with modems, and some
1031 computer mice used to be connected to serial ports before USB became
1032 commonplace.
1033 </para>
1034
1035 <para>While serial ports are no longer as ubiquitous as they used to be,
1036 there are still some important uses left for them. For example, serial
1037 ports can be used to set up a primitive network over a null-modem cable,
1038 in case Ethernet is not available. Also, serial ports are indispensable
1039 for system programmers needing to do kernel debugging, since kernel
1040 debugging software usually interacts with developers over a serial port.
1041 With virtual serial ports, system programmers can do kernel debugging on a
1042 virtual machine instead of needing a real computer to connect to.</para>
1043
1044 <para>If a virtual serial port is enabled, the guest operating system sees
1045 a standard 16550A compatible UART device. Both receiving and transmitting
1046 data is supported. How this virtual serial port is then connected to the
1047 host is configurable, and the details depend on your host operating system.
1048 </para>
1049
1050 <para>You can use either the graphical user interface or the command-line
1051 <computeroutput>VBoxManage</computeroutput> tool to set up virtual serial
1052 ports. For the latter, please refer to <xref
1053 linkend="vboxmanage-modifyvm" />; in that section, look for the
1054 <computeroutput>--uart</computeroutput> and
1055 <computeroutput>--uartmode</computeroutput> options.</para>
1056
1057 <para>In either case, you can configure up to four virtual serial ports per
1058 virtual machine. For each such device, you will need to
1059 determine<orderedlist>
1060 <listitem>
1061 <para>what kind of serial port the virtual machine should see by
1062 selecting an I/O base address and interrupt (IRQ). For these, we
1063 recommend to use the traditional values<footnote>
1064 <para>See, for example, <ulink
1065 url="http://en.wikipedia.org/wiki/COM_(hardware_interface)">http://en.wikipedia.org/wiki/COM_(hardware_interface)</ulink>.</para>
1066 </footnote>, which are:</para>
1067
1068 <para><orderedlist>
1069 <listitem>
1070 <para>COM1: I/O base 0x3F8, IRQ 4</para>
1071 </listitem>
1072
1073 <listitem>
1074 <para>COM2: I/O base 0x2F8, IRQ 3</para>
1075 </listitem>
1076
1077 <listitem>
1078 <para>COM3: I/O base 0x3E8, IRQ 4</para>
1079 </listitem>
1080
1081 <listitem>
1082 <para>COM4: I/O base 0x2E8, IRQ 3</para>
1083 </listitem>
1084 </orderedlist></para>
1085 </listitem>
1086
1087 <listitem>
1088 <para>Then, you will need to determine what this virtual port should
1089 be connected to. For each virtual serial port, you have the
1090 following options:</para>
1091
1092 <para><itemizedlist>
1093 <listitem>
1094 <para>You can elect to have the virtual serial port
1095 "disconnected", which means that the guest will see the
1096 device, but it will behave as if no cable had been connected
1097 to it.</para>
1098 </listitem>
1099
1100 <listitem>
1101 <para>You can connect the virtual serial port to a physical
1102 serial port on your host. (On a Windows host, this will be a
1103 name like <computeroutput>COM1</computeroutput>; on Linux or
1104 Solaris hosts, it will be a device node like
1105 <computeroutput>/dev/ttyS0</computeroutput>). VirtualBox will
1106 then simply redirect all data received from and sent to the
1107 virtual serial port to the physical device.</para>
1108 </listitem>
1109
1110 <listitem>
1111 <para>You can tell VirtualBox to connect the virtual serial
1112 port to a software pipe on the host. This depends on your host
1113 operating system:<itemizedlist>
1114 <listitem>
1115 <para>On a Windows host, data will be sent and received
1116 through a named pipe. The pipe name must be in the format
1117 <computeroutput>\\.\pipe\&lt;name&gt;</computeroutput>
1118 where <computeroutput>&lt;name&gt;</computeroutput> should
1119 identify the virtual machine but may be freely
1120 chosen.</para>
1121 </listitem>
1122
1123 <listitem>
1124 <para>On a Mac, Linux or Solaris host, a local
1125 domain socket is used instead. The socket filename must be
1126 chosen such that the user running VirtualBox has
1127 sufficient privileges to create and write to it. The
1128 <computeroutput>/tmp</computeroutput> directory is often a
1129 good candidate.</para>
1130 <para>On Linux there are various tools which can connect
1131 to a local domain socket or create one in server mode. The
1132 most flexible tool is
1133 <computeroutput>socat</computeroutput> and is available
1134 as part of many distributions.</para>
1135 </listitem>
1136 </itemizedlist></para>
1137
1138 <para>In this case, you can configure whether VirtualBox
1139 should create the named pipe (or, on non-Windows hosts, the
1140 local domain socket) itself or whether VirtualBox should
1141 assume that the pipe (or socket) exists already. With the
1142 <computeroutput>VBoxManage</computeroutput> command-line
1143 options, this is referred to as "server" or "client" mode,
1144 respectively.</para>
1145
1146 <para>For a direct connection between two virtual machines
1147 (corresponding to a null-modem cable), simply configure one VM
1148 to create a pipe/socket and another to attach to it.
1149 </para>
1150 </listitem>
1151
1152 <listitem>
1153 <para>You can send the virtual serial port output to a file.
1154 This option is very useful for capturing diagnostic output from
1155 a guest. Any file may be used for this purpose, as long as the
1156 user running VirtualBox has sufficient privileges to create and
1157 write to the file.
1158 </para>
1159 </listitem>
1160
1161 <listitem>
1162 <para>TCP Socket: Useful for forwarding serial traffic over TCP/IP,
1163 acting as a server, or it can act as a TCP client connecting to other
1164 servers. It allows a remote machine to directly connect to the guest's
1165 serial port via TCP.
1166 </para>
1167 <itemizedlist>
1168 <listitem>
1169 <para>TCP Server: Uncheck the
1170 <emphasis>Connect to existing pipe/socket</emphasis> checkbox and specify
1171 the <emphasis role="bold"><computeroutput>port</computeroutput></emphasis>
1172 number. Typically 23 or 2023. Note that on UNIX-like systems you will
1173 have to use a port a number greater than 1024 for regular users.
1174 </para>
1175 <para>
1176 The client can use software such as <computeroutput>PuTTY</computeroutput>
1177 or the <computeroutput>telnet</computeroutput> command line
1178 tool to access the TCP Server.
1179 </para>
1180 </listitem>
1181 <listitem>
1182 <para>TCP Client: To create a virtual null-modem cable over the Internet or
1183 LAN, the other side can connect via TCP by specifying <emphasis role="bold">
1184 <computeroutput>hostname:port</computeroutput></emphasis>. The TCP socket
1185 will act in client mode if check the <emphasis>Connect to existing pipe/socket</emphasis>
1186 checkbox.
1187 </para>
1188 </listitem>
1189 </itemizedlist>
1190 </listitem>
1191
1192 </itemizedlist></para>
1193 </listitem>
1194 </orderedlist>Up to four serial ports can be configured per virtual
1195 machine, but you can pick any port numbers out of the above. However,
1196 serial ports cannot reliably share interrupts; if both ports are to be
1197 used at the same time, they must use different interrupt levels, for
1198 example COM1 and COM2, but not COM1 and COM3.
1199 </para>
1200 </sect1>
1201
1202 <sect1>
1203 <title>USB support</title>
1204
1205 <sect2 id="settings-usb">
1206 <title>USB settings</title>
1207
1208 <para>The "USB" section in a virtual machine's Settings window allows
1209 you to configure VirtualBox's sophisticated USB support.</para>
1210
1211 <para>VirtualBox can allow virtual machines to access the USB devices on
1212 your host directly. To achieve this, VirtualBox presents the guest
1213 operating system with a virtual USB controller. As soon as the guest
1214 system starts using a USB device, it will appear as unavailable on the
1215 host.<note>
1216 <orderedlist>
1217 <listitem>
1218 <para>Be careful with USB devices that are currently in use on
1219 the host! For example, if you allow your guest to connect to
1220 your USB hard disk that is currently mounted on the host, when
1221 the guest is activated, it will be disconnected from the host
1222 without a proper shutdown. This may cause data loss.</para>
1223 </listitem>
1224
1225 <listitem>
1226 <para>Solaris hosts have a few known limitations regarding USB
1227 support; please see <xref linkend="KnownIssues" />.</para>
1228 </listitem>
1229 </orderedlist>
1230 </note></para>
1231
1232 <para>In addition to allowing a guest access to your local USB devices,
1233 VirtualBox even allows your guests to connect to remote USB devices by
1234 use of the VirtualBox Remote Desktop Extension (VRDE). For details about
1235 this, see <xref linkend="usb-over-rdp" />.</para>
1236
1237 <para>In the Settings dialog, you can first configure whether USB is
1238 available in the guest at all, and then choose the level of USB support:
1239 OHCI for USB 1.1, EHCI (which will also enable OHCI) for USB 2.0,
1240 or xHCI for all USB speeds. <note>
1241 <para>The xHCI and EHCI controllers are shipped as a VirtualBox extension
1242 package, which must be installed separately. See <xref
1243 linkend="intro-installing" /> for more information.</para>
1244 </note></para>
1245
1246 <para>When USB support is enabled for a VM, you can determine in detail
1247 which devices will be automatically attached to the guest. For this, you
1248 can create so-called "filters" by specifying certain properties of
1249 the USB device. USB devices with a matching filter will be automatically
1250 passed to the guest once they are attached to the host. USB devices
1251 without a matching filter can be passed manually to the guest, for
1252 example by using the Devices / USB devices menu.</para>
1253
1254 <para>Clicking on the "+" button to the right of the "USB Device
1255 Filters" window creates a <emphasis role="bold">new filter.</emphasis>
1256 You can give the filter a name (for referencing it later) and specify
1257 the filter criteria. The more criteria you specify, the more precisely
1258 devices will be selected. For instance, if you specify only a vendor ID
1259 of 046d, all devices produced by Logitech will be available to the
1260 guest. If you fill in all fields, on the other hand, the filter will
1261 only apply to a particular device model from a particular vendor, and
1262 not even to other devices of the same type with a different revision and
1263 serial number.</para>
1264
1265 <para>In detail, the following criteria are available:</para>
1266
1267 <orderedlist>
1268 <listitem>
1269 <para><emphasis role="bold">Vendor and product ID.</emphasis> With
1270 USB, each vendor of USB products carries an identification number
1271 that is unique world-wide, the "vendor ID". Similarly, each line of
1272 products is assigned a "product ID" number. Both numbers are
1273 commonly written in hexadecimal (that is, they are composed of the
1274 numbers 0-9 and the letters A-F), and a colon separates the vendor
1275 from the product ID. For example,
1276 <computeroutput>046d:c016</computeroutput> stands for Logitech as a
1277 vendor, and the "M-UV69a Optical Wheel Mouse" product.</para>
1278
1279 <para>Alternatively, you can also specify <emphasis
1280 role="bold">"Manufacturer"</emphasis> and <emphasis
1281 role="bold">"Product"</emphasis> by name.</para>
1282
1283 <para>To list all the USB devices that are connected to your host
1284 machine with their respective vendor and product IDs, you can use
1285 the following command (see <xref linkend="vboxmanage" />): <screen>VBoxManage list usbhost</screen></para>
1286
1287 <para>On Windows, you can also see all USB devices that are attached
1288 to your system in the Device Manager. On Linux, you can use the
1289 <computeroutput>lsusb</computeroutput> command.</para>
1290 </listitem>
1291
1292 <listitem>
1293 <para><emphasis role="bold">Serial number.</emphasis> While vendor
1294 and product ID are already quite specific to identify USB devices,
1295 if you have two identical devices of the same brand and product
1296 line, you will also need their serial numbers to filter them out
1297 correctly.</para>
1298 </listitem>
1299
1300 <listitem>
1301 <para><emphasis role="bold">Remote.</emphasis> This setting
1302 specifies whether the device will be local only, or remote only
1303 (over VRDP), or either.</para>
1304 </listitem>
1305 </orderedlist>
1306
1307 <para>On a Windows host, you will need to unplug and reconnect a USB
1308 device to use it after creating a filter for it.</para>
1309
1310 <para>As an example, you could create a new USB filter and specify a
1311 vendor ID of 046d (Logitech, Inc), a manufacturer index of 1, and "not
1312 remote". Then any USB devices on the host system produced by Logitech,
1313 Inc with a manufacturer index of 1 will be visible to the guest
1314 system.</para>
1315
1316 <para>Several filters can select a single device -- for example, a
1317 filter which selects all Logitech devices, and one which selects a
1318 particular webcam.</para>
1319
1320 <para>You can <emphasis role="bold">deactivate</emphasis> filters
1321 without deleting them by clicking in the checkbox next to the filter
1322 name.</para>
1323 </sect2>
1324
1325 <sect2>
1326 <title>Implementation notes for Windows and Linux hosts</title>
1327
1328 <para>On Windows hosts, a kernel mode device driver provides USB proxy
1329 support. It implements both a USB monitor, which allows VirtualBox to
1330 capture devices when they are plugged in, and a USB device driver to
1331 claim USB devices for a particular virtual machine. As opposed to
1332 VirtualBox versions before 1.4.0, system reboots are no longer necessary
1333 after installing the driver. Also, you no longer need to replug devices
1334 for VirtualBox to claim them.</para>
1335
1336 <para>On newer Linux hosts, VirtualBox accesses USB devices through
1337 special files in the file system. When VirtualBox is installed, these
1338 are made available to all users in the
1339 <computeroutput>vboxusers</computeroutput> system group. In order to be
1340 able to access USB from guest systems, make sure that you are a member
1341 of this group.</para>
1342
1343 <para>On older Linux hosts, USB devices are accessed using the
1344 <computeroutput>usbfs</computeroutput> file system. Therefore, the user
1345 executing VirtualBox needs read and write permission to the USB file
1346 system. Most distributions provide a group (e.g.
1347 <computeroutput>usbusers</computeroutput>) which the VirtualBox user
1348 needs to be added to. Also, VirtualBox can only proxy to virtual
1349 machines USB devices which are not claimed by a Linux host USB driver.
1350 The <computeroutput>Driver=</computeroutput> entry in
1351 <computeroutput>/proc/bus/usb/devices</computeroutput> will show you
1352 which devices are currently claimed. Please refer to <xref
1353 linkend="ts_usb-linux" /> also for details about
1354 <computeroutput>usbfs</computeroutput>.</para>
1355 </sect2>
1356 </sect1>
1357
1358 <sect1>
1359 <title>Shared folders</title>
1360
1361 <para>Shared folders allow you to easily exchange data between a virtual
1362 machine and your host. This feature requires that the VirtualBox Guest
1363 Additions be installed in a virtual machine and is described in detail in
1364 <xref linkend="sharedfolders" />.</para>
1365 </sect1>
1366
1367 <sect1>
1368 <title>User Interface</title>
1369
1370 <para>The "User Interface" section allows you to change certain aspects of
1371 the user interface of this VM.</para>
1372
1373 <para><glosslist>
1374 <glossentry>
1375 <glossterm>Menu Bar</glossterm>
1376 <glossdef>
1377 <para>This widget allows you to disable certain menus (click at
1378 the menu to release it), certain menu entries (uncheck the
1379 checkbox of the entry to disable it) and the complete menu bar
1380 (uncheck the rightmost checkbox).
1381 </para>
1382 </glossdef>
1383 </glossentry>
1384
1385 <glossentry>
1386 <glossterm>Mini ToolBar</glossterm>
1387 <glossdef>
1388 <para>In full screen or seamless mode, VirtualBox can display a
1389 small toolbar that contains some of the items that are normally
1390 available from the virtual machine's menu bar. This toolbar
1391 reduces itself to a small gray line unless you move the mouse
1392 over it. With the toolbar, you can return from full screen or
1393 seamless mode, control machine execution or enable certain
1394 devices. If you don't want to see the toolbar, disable this
1395 setting.</para>
1396 <para>The second setting allows to show the toolbar at the top
1397 of the screen instead of showing it at the bottom.</para>
1398 </glossdef>
1399 </glossentry>
1400
1401 <glossentry>
1402 <glossterm>Status Bar</glossterm>
1403 <glossdef>
1404 <para>This widget allows you to disable certain icons of the
1405 status bar (uncheck the checkbox of an icon to disable it),
1406 to re-arrange icons (drag and drop the icon) and to disable the
1407 complete status bar (uncheck the leftmost checkbox).</para>
1408 </glossdef>
1409 </glossentry>
1410 </glosslist></para>
1411
1412 </sect1>
1413
1414 <sect1 id="efi">
1415 <title>Alternative firmware (EFI)</title>
1416
1417 <para>Starting with release 3.1, VirtualBox includes experimental support
1418 for the Extensible Firmware Interface (EFI), which is a new industry
1419 standard intended to eventually replace the legacy BIOS as the primary
1420 interface for bootstrapping computers and certain system services
1421 later.</para>
1422
1423 <para>By default, VirtualBox uses the BIOS firmware for virtual machines.
1424 To use EFI for a given virtual machine, you can enable EFI in the
1425 machine's "Settings" dialog (see <xref linkend="settings-motherboard" />).
1426 Alternatively, use the <computeroutput>VBoxManage</computeroutput> command
1427 line interface like this: <screen>VBoxManage modifyvm "VM name" --firmware efi</screen>
1428 To switch back to using the BIOS, use: <screen>VBoxManage modifyvm "VM name" --firmware bios</screen>One
1429 notable user of EFI is Apple's Mac OS X, but more recent Linuxes
1430 and Windows (starting with Vista) offer special versions that can be
1431 booted using EFI as well.</para>
1432
1433 <para>Another possible use of EFI in VirtualBox is development and testing
1434 of EFI applications, without booting any OS.</para>
1435
1436 <para>Note that the VirtualBox EFI support is experimental and will be
1437 enhanced as EFI matures and becomes more widespread. Mac OS X, Linux
1438 and newer Windows guests are known to work fine. Windows 7 guests are
1439 unable to boot with the VirtualBox EFI implementation.</para>
1440
1441 <sect2 id="efividmode">
1442 <title>Video modes in EFI</title>
1443
1444 <para>EFI provides two distinct video interfaces: GOP (Graphics Output
1445 Protocol) and UGA (Universal Graphics Adapter). Mac OS X uses GOP, while
1446 Linux tends to use UGA. VirtualBox provides a configuration option to
1447 control the framebuffer size for both interfaces.</para>
1448
1449 <para>To control GOP, use the following
1450 <computeroutput>VBoxManage</computeroutput> command: <screen>VBoxManage setextradata "VM name" VBoxInternal2/EfiGopMode N</screen>
1451 Where N can be one of 0,1,2,3,4,5 referring to the 640x480, 800x600,
1452 1024x768, 1280x1024, 1440x900, 1920x1200 screen resolution respectively.</para>
1453
1454 <para>To change the UGA resolution: <screen>VBoxManage setextradata "VM name" VBoxInternal2/UgaHorizontalResolution 1440
1455VBoxManage setextradata "VM name" VBoxInternal2/UgaVerticalResolution 900</screen></para>
1456
1457 <para>The video mode for both GOP and UGA can only be changed when the
1458 VM is powered off and remains persistent until changed.</para>
1459 </sect2>
1460
1461 <sect2 id="efibootargs">
1462 <title>Specifying boot arguments</title>
1463
1464 <para>It is currently not possible to manipulate EFI variables from within a running guest
1465 (e.g., setting the "boot-args" variable by running the <computeroutput>nvram</computeroutput> tool in a Mac OS X guest will not work).
1466 As an alternative way, "VBoxInternal2/EfiBootArgs" extradata can be passed to a VM in order to set
1467 the "boot-args" variable. To change the "boot-args" EFI variable:
1468 <screen>VBoxManage setextradata "VM name" VBoxInternal2/EfiBootArgs &lt;value&gt;</screen>
1469 </para>
1470 </sect2>
1471
1472 </sect1>
1473</chapter>
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