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="KnownIssues">
|
---|
5 | <title>Known limitations</title>
|
---|
6 |
|
---|
7 | <para>This sections describes known problems with VirtualBox
|
---|
8 | $VBOX_VERSION_STRING. Unless marked otherwise, these issues are planned to
|
---|
9 | be fixed in later releases.</para>
|
---|
10 |
|
---|
11 | <itemizedlist>
|
---|
12 | <listitem>
|
---|
13 | <para>The following <emphasis role="bold">Guest SMP (multiprocessor)
|
---|
14 | limitations</emphasis> exist:<itemizedlist>
|
---|
15 | <listitem>
|
---|
16 | <para><emphasis role="bold">Poor performance</emphasis> with
|
---|
17 | 32-bit guests on AMD CPUs. This affects mainly Windows and Solaris
|
---|
18 | guests, but possibly also some Linux kernel revisions. Partially
|
---|
19 | solved in 3.0.6 for 32 bits Windows NT, 2000, XP and 2003 guests.
|
---|
20 | Requires 3.0.6 or higher Guest Additions to be installed.</para>
|
---|
21 | </listitem>
|
---|
22 |
|
---|
23 | <listitem>
|
---|
24 | <para><emphasis role="bold">Poor performance</emphasis> with
|
---|
25 | 32-bit guests on certain Intel CPU models that do not include
|
---|
26 | virtual APIC hardware optimization support. This affects mainly
|
---|
27 | Windows and Solaris guests, but possibly also some Linux kernel
|
---|
28 | revisions. Partially solved in 3.0.12 for 32 bits Windows NT,
|
---|
29 | 2000, XP and 2003 guests. Requires 3.0.12 or higher Guest
|
---|
30 | Additions to be installed.</para>
|
---|
31 | </listitem>
|
---|
32 |
|
---|
33 | </itemizedlist></para>
|
---|
34 | </listitem>
|
---|
35 |
|
---|
36 | <listitem>
|
---|
37 | <para><emphasis role="bold">64-bit guests on some 32-bit host systems
|
---|
38 | with VT-x</emphasis> can cause instabilities to your system. If you
|
---|
39 | experience this, do not attempt to execute 64-bit guests. Refer to the
|
---|
40 | VirtualBox user forum for additional information.</para>
|
---|
41 | </listitem>
|
---|
42 |
|
---|
43 | <listitem>
|
---|
44 | <para><emphasis role="bold">Direct 3D support in Windows
|
---|
45 | guests.</emphasis> For this to work, the Guest Additions must be
|
---|
46 | installed in Windows "safe mode". Press F8 when the Windows guest is
|
---|
47 | booting and select "Safe mode", then install the Guest Additions.
|
---|
48 | Otherwise Windows' file protection mechanism will interfere with the
|
---|
49 | replacement DLLs installed by VirtualBox and keep restoring the original
|
---|
50 | Windows system DLLs.</para>
|
---|
51 | </listitem>
|
---|
52 |
|
---|
53 | <listitem>
|
---|
54 | <para><emphasis role="bold">Guest multi-monitor support.</emphasis> This
|
---|
55 | feature is currently only supported with Windows guests.</para>
|
---|
56 | </listitem>
|
---|
57 |
|
---|
58 | <listitem>
|
---|
59 | <para><emphasis role="bold">Deleting the only snapshot with a running VM
|
---|
60 | is not implemented.</emphasis> Trying to perform this operation will
|
---|
61 | result in an error message. This feature will be added in one of the
|
---|
62 | next maintenance releases. It is possible to delete the only snapshot
|
---|
63 | when the VM is not running, e.g. in "poweroff" or "saved" state.</para>
|
---|
64 | </listitem>
|
---|
65 |
|
---|
66 | <listitem>
|
---|
67 | <para><emphasis role="bold">Disabled host I/O caches.</emphasis>
|
---|
68 | Disabling the host I/O cache (see <xref linkend="iocaching" />) will
|
---|
69 | yield poor performance with VHD and sparse VMDK files as these do not
|
---|
70 | currently support asynchronous I/O. This does not apply to VDI files and
|
---|
71 | raw disk/partition VMDK files, which do support async I/O. This
|
---|
72 | restriction will be lifted in a future maintenance update.</para>
|
---|
73 | </listitem>
|
---|
74 |
|
---|
75 | <listitem>
|
---|
76 | <para><emphasis role="bold">Compacting virtual disk images is limited to
|
---|
77 | VDI files.</emphasis> The <code>VBoxManage modifyhd --compact</code>
|
---|
78 | command is currently only implemented for VDI files. At the moment the
|
---|
79 | only way to optimize the size of a virtual disk images in other formats
|
---|
80 | (VMDK, VHD) is to clone the image and then use the cloned image in the
|
---|
81 | VM configuration.</para>
|
---|
82 | </listitem>
|
---|
83 |
|
---|
84 | <listitem>
|
---|
85 | <para><emphasis role="bold">OVF import/export:</emphasis><itemizedlist>
|
---|
86 | <listitem>
|
---|
87 | <para>When importing an OVF that was previously exported by
|
---|
88 | VirtualBox 3.2 or higher which contains a complete VirtualBox machine
|
---|
89 | configuration in the <vbox:Machine> element, some of the
|
---|
90 | import customizations that can be specified (in either the GUI or
|
---|
91 | on the VBoxManage command line) are presently ignored. In
|
---|
92 | particular, customizations of the imported storage configuration
|
---|
93 | are ignored. This will be fixed in the next release.</para>
|
---|
94 | </listitem>
|
---|
95 |
|
---|
96 | <listitem>
|
---|
97 | <para>OVF localization (multiple languages in one OVF file) is not
|
---|
98 | yet supported.</para>
|
---|
99 | </listitem>
|
---|
100 |
|
---|
101 | <listitem>
|
---|
102 | <para>Some OVF sections like StartupSection,
|
---|
103 | DeploymentOptionSection and InstallSection are ignored.</para>
|
---|
104 | </listitem>
|
---|
105 |
|
---|
106 | <listitem>
|
---|
107 | <para>OVF environment documents, including their property sections
|
---|
108 | and appliance configuration with ISO images, are not yet
|
---|
109 | supported.</para>
|
---|
110 | </listitem>
|
---|
111 |
|
---|
112 | <listitem>
|
---|
113 | <para>OVA archives (TAR containers) are not yet supported.</para>
|
---|
114 | </listitem>
|
---|
115 |
|
---|
116 | <listitem>
|
---|
117 | <para>Remote files via HTTP or other mechanisms are not yet
|
---|
118 | supported.</para>
|
---|
119 | </listitem>
|
---|
120 | </itemizedlist></para>
|
---|
121 | </listitem>
|
---|
122 |
|
---|
123 | <listitem>
|
---|
124 | <para><emphasis role="bold">Seamless mode</emphasis> does not work
|
---|
125 | correctly with Linux guests that have 3D effects enabled (such as with
|
---|
126 | compiz-enabled window managers).</para>
|
---|
127 | </listitem>
|
---|
128 |
|
---|
129 | <listitem>
|
---|
130 | <para><emphasis role="bold">Mac OS X hosts.</emphasis> The following
|
---|
131 | restrictions apply (all of which will be resolved in future
|
---|
132 | versions):<itemizedlist>
|
---|
133 | <listitem>
|
---|
134 | <para>The numlock emulation has not yet been implemented.</para>
|
---|
135 | </listitem>
|
---|
136 |
|
---|
137 | <listitem>
|
---|
138 | <para>The CPU frequency metric is not supported.</para>
|
---|
139 | </listitem>
|
---|
140 |
|
---|
141 | <listitem>
|
---|
142 | <para>3D OpenGL acceleration, in particular with Linux guests that
|
---|
143 | have 3D effects enabled (such as with compiz-enabled window
|
---|
144 | managers).</para>
|
---|
145 | </listitem>
|
---|
146 |
|
---|
147 | <listitem>
|
---|
148 | <para>Memory ballooning is not supported.</para>
|
---|
149 | </listitem>
|
---|
150 | </itemizedlist></para>
|
---|
151 | </listitem>
|
---|
152 |
|
---|
153 | <listitem>
|
---|
154 | <para><emphasis role="bold">Mac OS X Server guests.</emphasis>
|
---|
155 | <itemizedlist>
|
---|
156 | <listitem>
|
---|
157 | <para>Mac OS X Server guests can only run on a certain host
|
---|
158 | hardware. For details about license and host hardware limitations,
|
---|
159 | please see <xref linkend="intro-macosxguests" />.</para>
|
---|
160 | </listitem>
|
---|
161 |
|
---|
162 | <listitem>
|
---|
163 | <para>VirtualBox does not provide Guest Additions for Mac OS X
|
---|
164 | Server at this time.</para>
|
---|
165 | </listitem>
|
---|
166 |
|
---|
167 | <listitem>
|
---|
168 | <para>The graphics resolution currently defaults to 1024x768 as
|
---|
169 | Mac OS X Server falls back to the built-in EFI display support.
|
---|
170 | See <xref linkend="efividmode" /> for more information on how to
|
---|
171 | change EFI video modes.</para>
|
---|
172 | </listitem>
|
---|
173 |
|
---|
174 | <listitem>
|
---|
175 | <para>Even when idle, Mac OS X Server guests currently burn 100%
|
---|
176 | CPU. This is a power management issue that will be addressed in a
|
---|
177 | future release.</para>
|
---|
178 | </listitem>
|
---|
179 |
|
---|
180 | <listitem>
|
---|
181 | <para>Mac OS X Server guests only work with one CPU assigned to
|
---|
182 | the VM. Support for SMP will be provided in a future
|
---|
183 | release.</para>
|
---|
184 | </listitem>
|
---|
185 |
|
---|
186 | <listitem>
|
---|
187 | <para>Depending on your system and version of Mac OS X Server, you
|
---|
188 | might experience guest hangs after some time. This can be fixed by
|
---|
189 | turning off energy saving (set timeout to "Never") in the system
|
---|
190 | preferences.</para>
|
---|
191 | </listitem>
|
---|
192 |
|
---|
193 | <listitem>
|
---|
194 | <para>By default, the VirtualBox EFI enables debug output of the
|
---|
195 | Mac OS X Server kernel to help you diagnose boot problems. Note
|
---|
196 | that there is a lot of output and not all errors are fatal (they
|
---|
197 | would also show on your physical Mac). You can turn off these
|
---|
198 | messages by issuing this command:<screen>VBoxManage setextradata "VM name" "VBoxInternal2/EfiBootArgs" " "</screen>To
|
---|
199 | revert to the previous behavior, use:<screen>VBoxManage setextradata "VM name" "VBoxInternal2/EfiBootArgs" ""</screen></para>
|
---|
200 | </listitem>
|
---|
201 | </itemizedlist></para>
|
---|
202 | </listitem>
|
---|
203 |
|
---|
204 | <listitem>
|
---|
205 | <para><emphasis role="bold">Solaris hosts.</emphasis> The following
|
---|
206 | restrictions apply for OpenSolaris and Solaris 10:<itemizedlist>
|
---|
207 | <listitem>
|
---|
208 | <para>There is no support for USB devices connected to Solaris 10 hosts.</para>
|
---|
209 | </listitem>
|
---|
210 |
|
---|
211 | <listitem>
|
---|
212 | <para>USB support on OpenSolaris hosts requires version snv_124 or
|
---|
213 | higher. Webcams and other isochronous devices are known to have
|
---|
214 | poor performance.</para>
|
---|
215 | </listitem>
|
---|
216 |
|
---|
217 | <listitem>
|
---|
218 | <para>No ACPI information (battery status, power source) is
|
---|
219 | reported to the guest.</para>
|
---|
220 | </listitem>
|
---|
221 |
|
---|
222 | <listitem>
|
---|
223 | <para>No support for using wireless adapters with bridged
|
---|
224 | networking.</para>
|
---|
225 | </listitem>
|
---|
226 | </itemizedlist></para>
|
---|
227 | </listitem>
|
---|
228 |
|
---|
229 | <listitem>
|
---|
230 | <para><emphasis role="bold">Guest Additions for OS/2.</emphasis> Shared
|
---|
231 | folders are not yet supported with OS/2 guests. In addition, seamless
|
---|
232 | windows and automatic guest resizing will probably never be implemented
|
---|
233 | due to inherent limitations of the OS/2 graphics system.</para>
|
---|
234 | </listitem>
|
---|
235 | </itemizedlist>
|
---|
236 | </chapter>
|
---|